Some argue, with some justification, that the studies of coenzyme Q10 were not large enough, or were not long enough, or used various preparations and doses of coenzyme Q10.
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If you do take coenzyme Q10, seek your doctor's advice.
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It's the production of NAD — a coenzyme, a fuel that's used in a variety of reactions at the metabolic level — it was actually the production of this coenzyme that was decreasing in all of these living things.
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Their meta-analysis of 302 patients concluded that coenzyme Q10 was not beneficial.
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If so, could restoring coenzyme Q10 to normal levels with supplements counteract these problems?
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For example, Coenzyme Q₁₀, also known as CoQ10, is an enzyme naturally found in the human body.
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Q. Does coenzyme Q210 help to reduce muscular issues and other negative side effects associated with statins?
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In the ensuing years, coenzyme Q10 was studied extensively as a treatment for statin-induced muscle problems.
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As a result, statins not only lower cholesterol levels, they also deplete the body's stores of coenzyme Q10.
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Still, considering the preponderance of evidence, there is no proof coenzyme Q10 helps prevent statin-induced muscle problems.
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A subsequent randomized controlled trial of coenzyme Q10 in 41 patients with proven statin-induced muscle problems reached the same conclusion.
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A. Coenzyme Q103, a popular dietary supplement marketed as CoQ210 "to promote heart health," probably does not reduce statin-induced muscle problems.
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He swallows some ninety pills a day, including metformin; Basis; a coenzyme called Q10, for muscle strength; and phosphatidylcholine, to keep his skin supple.
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According to Brady, coenzyme Q10 is a commonly used antioxidant with reasonable supporting data for its use, though optimal dosing has yet to be determined.
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One of the things that Lenny and his constituencies in the research community had identified was that sirtuins are dependent on a coenzyme called NAD.
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This theory attracted many proponents, including Dr. Brown, who in 1989 filed a patent on coenzyme Q103 as a treatment for statin-induced muscle problems.
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Rigorous studies of coenzyme Q10 for other medical conditions — such as heart failure, Parkinson's disease and Huntington's disease — have also found it to be ineffective.
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How many of these purported brain boosters have you already tried — Ginkgo biloba, coenzyme Q2800, huperzine A, caprylic acid and coconut oil, coral calcium, among others?
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In addition to those drugs, he regularly used supplements that he purchased from a variety of online pharmacies: He was currently taking cinnamon and Coenzyme Q10.
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Like all dietary supplements, coenzyme Q10 is not regulated as a drug by the Food and Drug Administration, so there may be important differences between different manufacturer's products.
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In 2015, the Lipid and Blood Pressure Meta-analysis Collaboration Group combined data from six randomized controlled trials of coenzyme Q10 as a treatment for statin-induced muscle problems.
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I palmed a cocktail of Coenzyme Q10, a probiotic, a dandelion leaf liver-cleanse capsule, a magnesium energy supplement and, just to test my gag reflex, a spoonful of fish oil.
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In 1978, investigators, including Dr. Michael Brown and Dr. Joseph Goldstein, who would go on to win the Nobel Prize, noted that cholesterol and coenzyme Q10 are synthesized by the same biochemical pathway.
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The process involves dunking plants in a solution made out of luciferase, luciferin and coenzyme A (a combination of which creates fireflies' glow) and applying pressure that essentially forces the solution into plant pores.
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Created by Israel-based skin guru Mimi Luzon, the woman behind the models' treatments, the Pure 24K Gold Mask is chock-full of ingredients aimed at renewing skin cells (like peptides, red tea, hyaluronic acid, and coenzyme 10).
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Surprisingly, the contents of this single packet erased the flakiness around my nose and forehead, thanks to a stay-put sheet mask that was drenched in a serum of hyaluronic acid, peptides, coenzyme Q10, resveratrol, and plant stem cells.
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Coenzyme Q10, a nutritional supplement that acts as an antioxidant and is commonly taken for a variety of heart conditions, was tied to gains in sperm count, motility and shape in three of four studies lasting three to six months.
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This means sperm are very dependent on external sources of antioxidants, including vitamin C, vitamin E, beta carotene, zinc, selenium, folic acid, lycopene and coenzyme Q-10, which are found normally in the seminal fluid and help prevent damage to sperm cells.
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After accounting for other factors that might increase the risk of recurrence or death, they found patients who took any antioxidant at the outset and during chemotherapy - including carotenoids, Coenzyme Q10 and vitamins A, C, and E - were 193% more likely to have their breast cancer return and 40% more likely to die during follow-up compared to patients using no supplements.
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Coenzyme B is a coenzyme required for redox reactions in methanogens. The full chemical name of coenzyme B is 7-mercaptoheptanoylthreoninephosphate. The molecule contains a thiol, which is its principal site of reaction. Coenzyme B reacts with 2-methylthioethanesulfonate (methyl-Coenzyme M, abbreviated ), to release methane in methanogenesis: : + HS–CoB -> \+ CoB–S–S–CoM This conversion is catalyzed by the enzyme methyl coenzyme M reductase, which contains cofactor F430 as the prosthetic group.
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The coenzyme is the C1 donor in methanogenesis. It is converted to methyl-coenzyme M thioether, the thioether , in the penultimate step to methane formation. Methyl-coenzyme M reacts with coenzyme B, 7-thioheptanoylthreoninephosphate, to give a heterodisulfide, releasing methane: : + HS–CoB -> \+ CoB–S–S–CoM This induction is catalyzed by the enzyme methyl-coenzyme M reductase, which restricts cofactor F430 as the prosthetic group.
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Succinyl-coenzyme A, abbreviated as succinyl-CoA () or SucCoA, is a thioester of succinic acid and coenzyme A.
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Other names in common use include acetyl-CoA deacylase, acetyl-CoA acylase, acetyl coenzyme A hydrolase, acetyl coenzyme A deacylase, acetyl coenzyme A acylase, and acetyl-CoA thiol esterase. This enzyme participates in pyruvate metabolism.
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The systematic name of this enzyme class is acetyl-CoA:acetoacetyl-CoA C-acetyltransferase (thioester-hydrolysing, carboxymethyl-forming). Other names in common use include (S)-3-hydroxy-3-methylglutaryl-CoA acetoacetyl- CoA-lyase, (CoA-acetylating), 3-hydroxy-3-methylglutaryl CoA synthetase, 3-hydroxy-3-methylglutaryl coenzyme A synthase, 3-hydroxy-3-methylglutaryl coenzyme A synthetase, 3-hydroxy-3-methylglutaryl-CoA synthase, 3-hydroxy-3-methylglutaryl-coenzyme A synthase, beta-hydroxy-beta- methylglutaryl-CoA synthase, HMG-CoA synthase, acetoacetyl coenzyme A transacetase, hydroxymethylglutaryl coenzyme A synthase, and hydroxymethylglutaryl coenzyme A-condensing enzyme.
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In enzymology, a coenzyme F420 hydrogenase () is an enzyme that catalyzes the chemical reaction :H2 \+ coenzyme F420 \rightleftharpoons reduced coenzyme F420 Thus, the two substrates of this enzyme are H2 and coenzyme F420, whereas its product is reduced coenzyme F420. This enzyme belongs to the family of oxidoreductases, specifically those acting on hydrogen as donor with other, known, acceptors. The systematic name of this enzyme class is hydrogen:coenzyme F420 oxidoreductase. Other names in common use include 8-hydroxy-5-deazaflavin-reducing hydrogenase, F420-reducing hydrogenase, and coenzyme F420-dependent hydrogenase.
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Coumaroyl-coenzyme A is a chemical compound found in plants. The compound is the thioester of coenzyme-A and coumaric acid.
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Coenzyme Q10 supplementation is necessary to make up for the failure to synthesize Coenzyme Q10 and to lessen the resulting developmental difficulties.
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The biochemistry of methanogenesis involves the following coenzymes and cofactors: F420, coenzyme B, coenzyme M, methanofuran, and methanopterin. The mechanism for the conversion of bond into methane involves a ternary complex of methyl coenzyme M and coenzyme B fit into a channel terminated by the axial site on nickel of the cofactor F430. One proposed mechanism invokes electron transfer from Ni(I) (to give Ni(II)), which initiates formation of . Coupling of the coenzyme M thiyl radical (RS.) with HS coenzyme B releases a proton and re-reduces Ni(II) by one-electron, regenerating Ni(I).
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Coenzyme M is a coenzyme required for methyl-transfer reactions in the metabolism of methanogens. The coenzyme is an anion with the formula . It is named 2-mercaptoethanesulfonate and abbreviated HS–CoM. The cation is unimportant, but the sodium salt is most available.
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MLCL AT-1 catalyzes the transfer of the fatty acid chain attached to a coenzyme A molecule to an available hydroxyl group on MLCL, producing cardiolipin. This lipid remodeling is separate from the cardiolipin synthesis pathway, and is essential to maintain its unique unsaturated fatty acyl composition. MLCL AT-1 typically utilizes linoleoyl coenzyme A, preferred to oleoyl coenzyme A, which is preferred to palmitoyl coenzyme A.
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Structure of Coenzyme F420 Coenzyme F420 or 8-hydroxy-5-deazaflavin is a coenzyme (sometimes called a cofactor) involved in redox reactions in methanogens, in many Actinobacteria, and sporadically in other bacterial lineages. It is a flavin derivative. The coenzyme is a substrate for coenzyme F420 hydrogenase, 5,10-methylenetetrahydromethanopterin reductase and methylenetetrahydromethanopterin dehydrogenase. A particularly rich natural source of F420 is Mycobacterium smegmatis, in which several dozen enzymes use F420 instead of the related cofactor FMN used by homologous enzymes in most other species.
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The systematic name of this enzyme class is acyl- CoA:NADP+ 2-oxidoreductase. Other names in common use include 2-enoyl-CoA reductase, dehydrogenase, acyl coenzyme A (nicotinamide adenine dinucleotide, phosphate), enoyl coenzyme A reductase, crotonyl coenzyme A reductase, crotonyl-CoA reductase, and acyl-CoA dehydrogenase (NADP+).
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3-Methylcrotonyl-CoA or β-Methylcrotonyl-CoA is an intermediate in the metabolism of leucine. It is formed from isovaleryl-coenzyme A by isovaleryl coenzyme A dehydrogenase.
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Glucose-6-phosphate dehydrogenase (coenzyme-F420) (, coenzyme F420-dependent glucose-6-phosphate dehydrogenase, F420-dependent glucose-6-phosphate dehydrogenase, FGD1, Rv0407, F420-dependent glucose-6-phosphate dehydrogenase 1) is an enzyme with systematic name D-glucose-6-phosphate:F420 1-oxidoreductase. This enzyme catalyses the following chemical reaction : D-glucose 6-phosphate + oxidized coenzyme F420 \rightleftharpoons 6-phospho-D- glucono-1,5-lactone + reduced coenzyme F420 Thus enzyme is specific for D-glucose 6-phosphate.
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Coenzyme Q10 is not a fast-acting substance in heart failure. If the patient's condition is so severe that he or she does not have 40 – 60 to respond, then the CoQ10 treatment is likely to be ineffective. Once the patient responds to the Coenzyme Q10 treatment, however, and his or her heart function begins to improve, then the clinical course becomes more stable and the patient's condition is easier to manage. Improvement of one or two NYHA functional classes is likely. Coenzyme Q10 adjunctive treatment of heart failure patients is a long-term therapy because patients whose Coenzyme Q10 treatment is discontinued will suffer a clinical relapse. Clinical relapse after discontinuation of long-term Coenzyme Q10 therapy did not follow the same course as clinical relapse after discontinuation of short-term Coenzyme Q10 therapy. The relapse after the withdrawal of short-term Coenzyme Q10 therapy tended to be a rapid relapse followed by deterioration of heart function; the relapse after the withdrawal of long-term Coenzyme Q10 therapy was delayed and reduced by comparison. In summary, long-term management of severe heart failure patients with 100 milligrams of Coenzyme Q10 per day in conjunction with conventional therapy showed that 70% responded to the Coenzyme Q10 treatment albeit fairly slowly.
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Coenzyme Q10 deficiency is a deficiency of Coenzyme Q10. It can be associated with COQ2, APTX, PDSS2, PDSS1, CABC1, and COQ9. Some forms may be more treatable than other mitochondrial diseases.
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Coenzyme Q10 has potential to inhibit the effects of theophylline as well as the anticoagulant warfarin; coenzyme Q10 may interfere with warfarin's actions by interacting with cytochrome p450 enzymes thereby reducing the INR, a measure of blood clotting. The structure of coenzyme Q10 is very similar to that of vitamin K, which competes with and counteracts warfarin's anticoagulation effects. Coenzyme Q10 should be avoided in patients currently taking warfarin due to the increased risk of clotting.
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Coenzyme Q10 supplementation did not improve heart function quickly but did result in significantly increased long-term improvement. Furthermore, if the Coenzyme Q10 treatment was discontinued, then the patients’ heart function gradually decreased. In 1991, Judy reported the subsequent findings from the long-term management of heart failure patients with adjunctive Coenzyme Q10 treatment. He reported that Coenzyme Q10 is a safe and naturally occurring mediator of the process of cellular bio- energetics well-suited for long-term use.
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Binding of the NADPH coenzyme causes a massive conformational change, reorienting a loop, effectively locking the coenzyme in place. This binding is more similar to FAD- than to NAD(P)-binding oxidoreductases.
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Sporobolomyces species produce ballistoconidia that are bilaterally symmetrical, they have Coenzyme Q10 or Coenzyme Q10(H2) as their major ubiquinone, they lack xylose in whole-cell hydrolysates, and they cannot ferment sugars.
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Bempedoyl-CoA, the active metabolite. Coenzyme A is shown in blue. Bempedoic acid is a prodrug. It is activated to the thioester with coenzyme A by the enzyme SLC27A2 in the liver.
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5.1 hydrogen:quinone oxidoreductase : H2 \+ menaquinone menaquinol ;EC 1.12.7.2 ferredoxin hydrogenase (hydrogen:ferredoxin oxidoreductase) : H2 \+ oxidized ferredoxin 2H+ \+ reduced ferredoxin ;EC 1.12.98.1 coenzyme F420 hydrogenase (hydrogen:coenzyme F420 oxidoreductase) : H2 \+ coenzyme F420 reduced coenzyme F420 ;EC 1.12.99.6 hydrogenase (acceptor) (hydrogen:acceptor oxidoreductase) : H2 \+ A AH2 ;EC 1.12.98.2 5,10-methenyltetrahydromethanopterin hydrogenase (hydrogen:5,10-methenyltetrahydromethanopterin oxidoreductase) : H2 \+ 5,10-methenyltetrahydromethanopterin H+ \+ 5,10-methylenetetrahydromethanopterin ;EC 1.12.
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This pathway is regulated by product inhibition. CoA is a competitive inhibitor for Pantothenate Kinase, which normally binds ATP. Coenzyme A, three ADP, one monophosphate, and one diphosphate are harvested from biosynthesis. New research shows that coenzyme A can be synthesized through alternate routes when intracellular coenzyme A level are reduced and the de novo pathway is impaired.
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In enzymology, a 5,10-methylenetetrahydromethanopterin reductase () is an enzyme that catalyzes the chemical reaction :5-methyltetrahydromethanopterin + coenzyme F420 \rightleftharpoons 5,10-methylenetetrahydromethanopterin + reduced coenzyme F420 Thus, the two substrates of this enzyme are 5-methyltetrahydromethanopterin and coenzyme F420, whereas its two products are 5,10-methylenetetrahydromethanopterin and reduced coenzyme F420. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH group of donors with other acceptors. The systematic name of this enzyme class is 5-methyltetrahydromethanopterin:coenzyme-F420 oxidoreductase. Other names in common use include 5,10-methylenetetrahydromethanopterin cyclohydrolase, N5,N10-methylenetetrahydromethanopterin reductase, methylene-H4MPT reductase, coenzyme F420-dependent N5,N10-methenyltetrahydromethanopterin, reductase, and N5,N10-methylenetetrahydromethanopterin:coenzyme-F420 oxidoreductase.
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The poorest responders to the Coenzyme Q10 treatment were the oldest and most severe patients with the highest PSA, the largest prostate glands, and metastasis to adjacent tissues and bones [10]. In the responders, blood Coenzyme Q10 levels increased five-fold with the supplementation, and lymphocyte counts increased to normal levels. In non-responders, the blood Coenzyme Q10 levels increased only two-fold, and the lymphocyte counts remained essentially unchanged. Judy and Dr. Folkers suggested that Coenzyme Q10 stimulation of immunoglobulin G antibodies and T4/T8 lymphocytes as well as possible positive effects of Coenzyme Q10 on cytotoxic T-cells might explain the observed prostate cancer regression.
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This enzyme participates in coenzyme A (CoA) biosynthesis from pantothenic acid.
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This discovery was used to re-engineer coenzyme specificities of enzymes.
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Cinnamoyl-Coenzyme A is an intermediate in the phenylpropanoids metabolic pathway.
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Crotonyl-CoA reductase (, butyryl-CoA dehydrogenase, butyryl dehydrogenase, unsaturated acyl-CoA reductase, ethylene reductase, enoyl-coenzyme A reductase, unsaturated acyl coenzyme A reductase, butyryl coenzyme A dehydrogenase, short-chain acyl CoA dehydrogenase, short-chain acyl-coenzyme A dehydrogenase, 3-hydroxyacyl CoA reductase, butanoyl-CoA:(acceptor) 2,3-oxidoreductase, CCR) is an enzyme with systematic name butanoyl-CoA:NADP+ 2,3-oxidoreductase. This enzyme catalyses the following chemical reaction : butanoyl-CoA + NADP+ \rightleftharpoons (E)-but-2-enoyl-CoA + NADPH + H+ This enzyme catalyses the reaction in the reverse direction.
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The children who were of an age to be able to walk but could not walk because of muscle weakness began to take their first steps two to three weeks after they started on the Coenzyme Q10 treatment. In 2000, Judy together with his colleague Dr. Stogsdill started the Cyto-Med company, which supplies Coenzyme Q10 to children with Prader-Willi syndrome. Cyto-Med ships Coenzyme Q10 to children in 14 different countries. Prader-Willi children's cells cannot synthesize adequate quantities of Coenzyme Q10.
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This locus represents a mitochondrial ubiquinone biosynthesis gene. The encoded protein is likely necessary for biosynthesis of coenzyme Q10, as mutations at this locus have been associated with autosomal-recessive neonatal-onset primary coenzyme Q10 deficiency.
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Methylisocitrate lyase is used in the methylcitrate cycle, a modified version of the Krebs cycle that metabolizes propionyl coenzyme A instead of acetyl coenzyme A. The enzyme 2-methylcitrate synthase adds propionyl coenzyme A to oxaloacetate, yielding methylcitrate instead of citrate. But isomerizing methylcitrate to methylisocitrate and then subjecting it to MICL regenerates succinate, which proceeds as in the Krebs cycle, and pyruvate, which is easily metabolized by other pathways (e.g. decarboxylated to form acetyl coenzyme A and oxidized in the Krebs cycle). This allows catabolism of propionic acid—and, using beta oxidation, other fatty acids with odd numbers of carbons—without relying on coenzyme B12, a complex cofactor often used to metabolize propionate.
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In enzymology, a glutathione—CoA-glutathione transhydrogenase () is an enzyme that catalyzes the chemical reaction :CoA + glutathione disulfide \rightleftharpoons CoA-glutathione + glutathione Thus, the two substrates of this enzyme are CoA and glutathione disulfide, whereas its two products are CoA-glutathione and glutathione. This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with a disulfide as acceptor. The systematic name of this enzyme class is CoA:glutathione-disulfide oxidoreductase. Other names in common use include glutathione-coenzyme A glutathione disulfide transhydrogenase, glutathione- coenzyme A glutathione disulfide transhydrogenase, glutathione coenzyme A-glutathione transhydrogenase, glutathione:coenzyme A-glutathione transhydrogenase, coenzyme A:oxidized-glutathione oxidoreductase, and coenzyme A:glutathione-disulfide oxidoreductase.
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3-Ketoacyl-CoA thiolase, peroxisomal also known as acetyl-Coenzyme A acyltransferase 1 is an enzyme that in humans is encoded by the ACAA1 gene. Acetyl-Coenzyme A acyltransferase 1 is an acetyl-CoA C-acyltransferase enzyme.
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3-Ketoacyl-CoA thiolase, mitochondrial also known as acetyl-Coenzyme A acyltransferase 2 is an enzyme that in humans is encoded by the ACAA2 gene. Acetyl-Coenzyme A acyltransferase 2 is an acetyl-CoA C-acyltransferase enzyme.
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Coenzyme A (CoA, SHCoA, CoASH) is a coenzyme, notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle. All genomes sequenced to date encode enzymes that use coenzyme A as a substrate, and around 4% of cellular enzymes use it (or a thioester) as a substrate. In humans, CoA biosynthesis requires cysteine, pantothenate (vitamin B5), and adenosine triphosphate (ATP). In its acetyl form, coenzyme A is a highly versatile molecule, serving metabolic functions in both the anabolic and catabolic pathways.
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In enzymology, a methylenetetrahydromethanopterin dehydrogenase () is an enzyme that catalyzes the chemical reaction :5,10-methylenetetrahydromethanopterin + coenzyme F420 \rightleftharpoons 5,10-methenyltetrahydromethanopterin + reduced coenzyme F420 Thus, the two substrates of this enzyme are 5,10-methylenetetrahydromethanopterin and coenzyme F420, whereas its two products are 5,10-methenyltetrahydromethanopterin and reduced coenzyme F420. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH- NH group of donors with other acceptors. The systematic name of this enzyme class is 5,10-methylenetetrahydromethanopterin:coenzyme-F420 oxidoreductase. Other names in common use include N5,N10-methylenetetrahydromethanopterin dehydrogenase, and 5,10-methylenetetrahydromethanopterin dehydrogenase.
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In 1993, Judy reported the results of a clinical trial of the efficacy of Coenzyme Q10 supplementation of heart surgery patients. One group of patients received 100 milligrams of Coenzyme Q10 per day for 14 days prior to the surgery and for 30 days following the surgery. The other group of patients received a placebo for the same periods. Patients in both groups had a documented blood Coenzyme Q10 deficiency (< 0.6 micrograms per milliliter), low cardiac index (< 2.4 l/m2 per minute), and low left ventricular ejection fraction (< 35%) prior to the Coenzyme Q10 treatment.
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Pre-surgery supplementation improved blood Coenzyme Q10 and heart muscle tissue Coenzyme Q10 levels and heart muscle tissue ATP significantly compared to the placebo supplementation. Cardiac index and ejection fraction also improved but not to the level of statistical significance. Post-surgery supplementation was positively associated with the maintenance of normal blood and heart muscle tissue Coenzyme Q10 levels and normal heart muscle tissue ATP levels and with significantly improved cardiac index and ejection fraction. The course of recovery in the Coenzyme Q10 supplemented group was short (3–5 days) and uncomplicated.
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The increased dosage of Coenzyme Q10 yielded greater effectiveness. By 180 days, patients in both groups had experienced significant improvements in exercise tolerance and recovery time. Interestingly, despite the statistically significant increases, the chronic fatigue syndrome patients supplemented with Coenzyme Q10 could not reach the exercise tolerance levels of normal individuals, at least not within 180 days of supplementation. When the patients taking the Coenzyme Q10 were switched over to placebo, they reverted to the pre-Coenzyme Q10 treatment levels with 60 days (the 100-milligram group) and 90 days (the 300-milligam group).
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Other names in common use include long-chain fatty-acyl-CoA hydrolase, palmitoyl coenzyme A hydrolase, palmitoyl thioesterase, palmitoyl coenzyme A hydrolase, palmitoyl-CoA deacylase, palmityl thioesterase, palmityl-CoA deacylase, fatty acyl thioesterase I, and palmityl thioesterase I.
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He was able to isolate and purify the factor from pig liver and discovered that its function was related to a coenzyme that was active in choline acetylation. The coenzyme was named coenzyme A to stand for "activation of acetate". In 1953, Fritz Lipmann won the Nobel Prize in Physiology or Medicine "for his discovery of co-enzyme A and its importance for intermediary metabolism".
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Alternatively, β-alanine can be diverted into pantothenic acid and coenzyme A biosynthesis.
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Glutaryl-coenzyme A is an intermediate in the metabolism of lysine and tryptophan.
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Flavin mononucleotide binding domain interacts with a coenzyme of flavoprotein oxidoreductase enzymes, FMN.
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Acetyl-CoA acetyltransferase, cytosolic, also known as cytosolic acetoacetyl- CoA thiolase, is an enzyme that in humans is encoded by the ACAT2 (acetyl- Coenzyme A acetyltransferase 2) gene Acetyl-Coenzyme A acetyltransferase 2 is an acetyl-CoA C-acetyltransferase enzyme.
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In enzymology, a 3-oxoacid CoA-transferase () is an enzyme that catalyzes the chemical reaction :succinyl-CoA + a 3-oxo acid \rightleftharpoons succinate + a 3-oxoacyl-CoA Thus, the two substrates of this enzyme are succinyl-CoA and 3-oxo acid, whereas its two products are succinate and 3-oxoacyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA- transferases. The systematic name of this enzyme class is succinyl-CoA:3-oxo- acid CoA-transferase. Other names in common use include 3-oxoacid coenzyme A-transferase, 3-ketoacid CoA-transferase, 3-ketoacid coenzyme A transferase, 3-oxo-CoA transferase, 3-oxoacid CoA dehydrogenase, acetoacetate succinyl-CoA transferase, acetoacetyl coenzyme A-succinic thiophorase, succinyl coenzyme A-acetoacetyl coenzyme A-transferase, and succinyl-CoA transferase.
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Pharma Nord's coenzyme Q10 preparation is the official reference product for the International Coenzyme Q10 Association (ICQA).HomePage Pharma Nord actively supports scientific research into the health benefits of coenzyme Q10, primarily in relation to cardiology. Q-Symbio, a large multinational study investigating coenzyme Q10's potential as an adjuvant for treating chronic heart failure was published in the Journal of the American College of Cardiology, HEART FAILURE.The Effect of Coenzyme Q10 on Morbidity and Mortality in Chronic Heart Failure Results From Q-SYMBIO: A Randomized Double-Blind Trial The Q-Symbio study randomised 420 patients with severe heart failure (New York Heart Association (NYHA) Class III or IV) to CoQ10 (ubiquinone) or placebo and followed each patient for a period of two years.
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He matched the Prader-Willi children in the study with normal children of similar age and sex. The Prader-Willi children in the study had a mean plasma Coenzyme Q10 concentration of 0.38 micrograms per milliliter. The children tolerated the Coenzyme Q10 treatment well. The children who were receiving tube feeding because they were too weak to suckle began to suckle 10 days after the initiation of the Coenzyme Q10 supplementation.
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Because pyrithiamine pyrophosphate does not substitute for TPP as a coenzyme, the cell dies.
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Short-chain acyl-CoA dehydrogenase (, butyryl-CoA dehydrogenase, butanoyl-CoA dehydrogenase, butyryl dehydrogenase, unsaturated acyl-CoA reductase, ethylene reductase, enoyl-coenzyme A reductase, unsaturated acyl coenzyme A reductase, butyryl coenzyme A dehydrogenase, short-chain acyl CoA dehydrogenase, short- chain acyl-coenzyme A dehydrogenase, 3-hydroxyacyl CoA reductase, butanoyl- CoA:(acceptor) 2,3-oxidoreductase, ACADS (gene).) is an enzyme with systematic name short-chain acyl-CoA:electron-transfer flavoprotein 2,3-oxidoreductase. This enzyme catalyses the following chemical reaction : a short-chain acyl-CoA + electron-transfer flavoprotein \rightleftharpoons a short-chain trans-2,3-dehydroacyl-CoA + reduced electron-transfer flavoprotein This enzyme contains FAD as prosthetic group.
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William V. Judy, Ph.D. (born April 16, 1938) is an American author, clinical researcher, clinical trial consultant, and retired professor of physiology and biophysics. He was first introduced to the field of Coenzyme Q10 clinical research by Dr. Karl Folkers, the American bio-chemist who determined the structure of the Coenzyme Q10 molecule. Judy has managed randomized controlled trials into the safety and efficacy of Coenzyme Q10 supplementation for heart failure patients, chronic fatigue syndrome patients, Parkinson's disease patients, and prostate cancer patients. He has been instrumental in the treating of children with Prader-Willi syndrome with Coenzyme Q10.
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Coenzyme Q6 monooxygenase is a protein that in humans is encoded by the COQ6 gene.
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Bifunctional coenzyme A synthase is an enzyme that in humans is encoded by the COASY gene.
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Peak improvements came, typically, within 8–12 months. Survival (1–8 years) in the Coenzyme Q10 group was greater than in a matched control group (n=90) treated with conventional drugs only. The results of this early study showed that long-term Coenzyme Q10 therapy is safe, is effective in chronic heart failure patients with measurable CoQ10 deficiency, and is associated with improved long-term survival compared to conventionally treated patients. Judy's clinical studies of Coenzyme Q10 supplementation of heart failure patients are the forerunners of the international multi-center Q-Symbio Study of the Effect of Coenzyme Q10 on Morbidity and Mortality in Chronic Heart Failure.
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In these pathways, coenzyme A needs to be provided from an external source, such as food, in order to produce 4′-phosphopantetheine. Ectonucleotide pyrophosphates (ENPP) degrade coenzyme A to 4′-phosphopantetheine, a stable molecule in organisms. Acyl carrier proteins (ACP) (such as ACP synthase and ACP degradation) are also used to produce 4′-phosphopantetheine. This pathways allows for 4′-phosphopantetheine to be replenished in the cell and allows for the conversion to coenzyme A through enzymes, PPAT and PPCK.
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By sequence analyses of the large oxidoreductase type of enzyme families, he noted that the FAD-binding site is a classical Rossmann fold, but the NADPH binding site has a different consensus sequence that could be responsible for NAD vs. NADP coenzyme specificity. The importance of the motifs he identified was confirmed by re-engineering of coenzyme specificities of different enzymes. Elucidation of the crystal structure of adrenodoxin reductase further verified Israel's identification of the coenzyme binding sites.
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Structure of coenzyme A: 1: 3′-phosphoadenosine. 2: diphosphate, organophosphate anhydride. 3: pantoic acid. 4: β-alanine.
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Hydroxyacyl-Coenzyme A dehydrogenase (HADH) is an enzyme which in humans is encoded by the HADH gene.
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Acyl-coenzyme A thioesterase 4 is an enzyme that in humans is encoded by the ACOT4 gene.
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Structure of coenzyme A: 1: 3′-phosphoadenosine. 2: diphosphate, organophosphate anhydride. 3: pantoic acid. 4: β-alanine.
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The results of the Coenzyme Q10 treatment were even more impressive in the European sub-study. Treatment with Coenzyme Q10 300 milligrams per day in addition to conventional heart failure medications was safe, well tolerated, and effective at reducing symptoms and improving survival rates of chronic heart failure patients.
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Glutaryl-CoA dehydrogenase (non-decarboxylating) (, GDHDes, nondecarboxylating glutaryl-coenzyme A dehydrogenase, nondecarboxylating glutaconyl-coenzyme A-forming GDH) is an enzyme with systematic name glutaryl-CoA:acceptor 2,3-oxidoreductase (non-decarboxylating). This enzyme catalyses the following chemical reaction : glutaryl-CoA + acceptor \rightleftharpoons (E)-glutaconyl- CoA + reduced acceptor The enzyme contains FAD.
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Fritz Albert Lipmann (June 12, 1899 – July 24, 1986) was a German-American biochemist and a co-discoverer in 1945 of coenzyme A. For this, together with other research on coenzyme A, he was awarded the Nobel Prize in Physiology or Medicine in 1953 (shared with Hans Adolf Krebs).
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Tetrahydromethanopterin ('THMPT, ') is a coenzyme in methanogenesis. It is the carrier of the C1 group as it is reduced to the methyl level, before transferring to the coenzyme M. Tetrahydrosarcinapterin (THSPT, ) is a modified form of THMPT, wherein a glutamyl group linked to the 2-hydroxyglutaric acid terminus.
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These Coenzyme Q10-treated patients could take a significantly higher total accumulated dosage of adriamycin without any significant changes in cardiac hemodynamics or kinetics as compared to chemotherapy patients not on Coenzyme Q10. In the cancer patients with low cardiac function prior to the initiation of therapy, Coenzyme Q10 treatment did not produce the same beneficial results. Judy interpreted this outcome as an indication that patients with baseline low cardiac function are at risk for cardio-toxicity caused by adriamycin therapy.
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Acyl-coenzyme A synthetase ACSM2B, mitochondrial is an enzyme that in humans is encoded by the ACSM2B gene.
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Acyl-coenzyme A synthetase ACSM3, mitochondrial is an enzyme that in humans is encoded by the ACSM3 gene.
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It is a starting compound in the synthesis of coenzyme A (CoA), a cofactor for many enzyme processes.
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Tyrosine (or its precursor phenylalanine) is needed to synthesize the benzoquinone structure which forms part of coenzyme Q10.
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In enzymology, a hydroxymethylglutaryl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :(S)-3-hydroxy-3-methylglutaryl-CoA + H2O \rightleftharpoons CoA + 3-hydroxy-3-methylglutarate Thus, the two substrates of this enzyme are (S)-3-hydroxy-3-methylglutaryl-CoA and H2O, whereas its two products are CoA and 3-hydroxy-3-methylglutarate. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is (S)-3-hydroxy-3-methylglutaryl-CoA hydrolase. Other names in common use include beta-hydroxy-beta-methylglutaryl coenzyme A hydrolase, beta-hydroxy-beta-methylglutaryl coenzyme A deacylase, hydroxymethylglutaryl coenzyme A hydrolase, hydroxymethylglutaryl coenzyme A deacylase, and 3-hydroxy-3-methylglutaryl-CoA hydrolase.
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In a 1984 study, Judy reported that Coenzyme Q10 supplementation could help to offset the inhibitory effects of the chemotherapy drug adriamycin (doxorubicin) on the bio-synthesis of Coenzyme Q10 and could alleviate the cardio-toxicity of the drug. Adriamycin is an established chemotherapeutic drug with known anti-tumor effects; however, its use was limited by its documented cardio-toxicity at higher dosages. In the study, Judy and his co-researchers started the Coenzyme Q10 supplementation at a dosage of 100 milligrams per day three to five days before the adriamycin treatment began. The Coenzyme Q10 treatment proved to be effective in cancer patients with normal cardiac function prior to the commencement of the adriamycin treatment.
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In enzymology, a 4-coumarate-CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + 4-coumarate + CoA \rightleftharpoons AMP + diphosphate + 4-coumaroyl-CoA The 3 substrates of this enzyme are ATP, 4-coumarate, and CoA, whereas its 3 products are AMP, diphosphate, and 4-coumaroyl-CoA. This enzyme belongs to the family of ligases, to be specific those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is 4-coumarate:CoA ligase (AMP-forming). Other names in common use include 4-coumaroyl-CoA synthetase, p-coumaroyl CoA ligase, p-coumaryl coenzyme A synthetase, p-coumaryl-CoA synthetase, p-coumaryl-CoA ligase, feruloyl CoA ligase, hydroxycinnamoyl CoA synthetase, 4-coumarate:coenzyme A ligase, caffeoyl coenzyme A synthetase, p-hydroxycinnamoyl coenzyme A synthetase, feruloyl coenzyme A synthetase, sinapoyl coenzyme A synthetase, 4-coumaryl-CoA synthetase, hydroxycinnamate:CoA ligase, p-coumaryl-CoA ligase, p-hydroxycinnamic acid:CoA ligase, and 4CL.
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Dr. Folkers and Judy did case studies of the effects of Coenzyme Q10 on various cancers in patients with congestive heart failure. Coenzyme Q10 put the cancers into remission, improved heart function, and reduced the degree of heart failure. In 1998, Judy reported that PSA and prostate mass decreased following the treatment of prostate cancer patients with high dosages of Coenzyme Q10 (600 milligrams per day). However, the Coenzyme Q10 treatment did not take effect rapidly. It took 60 – 80 days before the researchers began to see a drop in the PSA scores and the prostate mass measurements. By 180 days of supplementation, PSA and prostate mass were significantly reduced in all of the responding patients. At 360 days of supplementation, PSA and prostate mass were reduced by 73.6% and 48.4%, respectively. Younger early-onset prostate cancer patients were the best responders to the Coenzyme Q10 treatment.
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This usually uses a prosthetic group or a coenzyme, forming electrophilic alpha and beta unsaturated carbonyl compounds and imines.
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Isovaleryl-coenzyme A, also known as isovaleryl-CoA, is an intermediate in the metabolism of branched-chain amino acids.
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For the reaction to complete, aminotransferases require participation of aldehyde containing coenzyme, pyridoxal-5'-phosphate (PLP), a derivative of Pyridoxine (Vitamin B6). The amino group is accommodated by conversion of this coenzyme to pyridoxamine-5'-phosphate (PMP). PLP is covalently attached to the enzyme via a Schiff Base linkage formed by the condensation of its aldehyde group with the ε-amino group of an enzymatic Lys residue. The Schiff base, which is conjugated to the enzymes pyridinium ring is the focus of the coenzyme activity.
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This step is catalyzed by methylene H4MPT dehydrogenase. :HCO-H4MPT + H+ -> CH-H4MPT+ + H2O (Formyl-H4MPT reduction) :CH-H4MPT+ + F420H2 -> CH2=H4MPT + F420 + H+(Methenyl-H4MPT hydrolysis) :CH2=H4MPT + H2 -> CH3-H4MPT + H+(H4MPT reduction) Next, the methyl group of methyl-M4MPT is transferred to coenzyme M via a methyltransferase-catalyzed reaction. :CH3-H4MPT + HS-CoM -> CH3-S-CoM + H4MPT The final step of H2/CO2 methanogenic involves methyl-coenzyme M reductase and two coenzymes: N-7 mercaptoheptanoylthreonine phosphate (HS-HTP) and coenzyme F430.
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This enzyme participates in d-arginine and d-ornithine metabolism. It has 3 cofactors: pyridoxal phosphate, Cobamide coenzyme, and Dithiothreitol.
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Formyl-CoA transferase （）mediates the exchange of oxalyl and formyl groups on coenzyme A, interconverting formyl-CoA and oxalyl- CoA.
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In enzymology, a succinate-CoA ligase (GDP-forming) () is an enzyme that catalyzes the chemical reaction :GTP + succinate + CoA \rightleftharpoons GDP + phosphate + succinyl-CoA The 3 substrates of this enzyme are GTP, succinate, and CoA, whereas its 3 products are GDP, phosphate, and succinyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon- sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is succinate:CoA ligase (GDP-forming). Other names in common use include succinyl-CoA synthetase (GDP-forming), succinyl coenzyme A synthetase (guanosine diphosphate-forming), succinate thiokinase, succinic thiokinase, succinyl coenzyme A synthetase, succinate-phosphorylating enzyme, P-enzyme, SCS, G-STK, succinyl coenzyme A synthetase (GDP-forming), succinyl CoA synthetase, and succinyl coenzyme A synthetase.
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In addition to chronic fatigue syndrome and chronic heart failure, there are numerous low-energy conditions to which the bio-energetic effects of Coenzyme Q10 can plausibly be extended: fibromyalgia, Huntington's chorea, muscular dystrophy, multiple sclerosis, Parkinson's disease, Prader-Willi syndrome, and some forms of cancers. Once humans reach adulthood, Coenzyme Q10 bio-synthesis begins to decrease with increasing age, resulting in less energy. The KiSel-10 Study of combined Coenzyme Q10 and selenium supplementation of senior citizens for years has shown that daily supplementation with 2 times 100 milligrams of Coenzyme Q10 and 200 micrograms of selenium is associated with significant reduction of cardiovascular mortality, significant improvement of heart function, and significant improvement of health-related quality of life.
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In enzymology, a lactoyl-CoA dehydratase () is an enzyme that catalyzes the chemical reaction :lactoyl-CoA \rightleftharpoons acryloyl-CoA + H2O Hence, this enzyme has one substrate, lactoyl-CoA, and two products, acryloyl-CoA and H2O. This enzyme belongs to the family of lyases, specifically the hydro- lyases, which cleave carbon-oxygen bonds. The systematic name of this enzyme class is lactoyl-CoA hydro-lyase (acryloyl-CoA-forming). Other names in common use include lactoyl coenzyme A dehydratase, lactyl-coenzyme A dehydrase, lactyl CoA dehydratase, acrylyl coenzyme A hydratase, and lactoyl-CoA hydro- lyase.
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Coenzyme A is available from various chemical suppliers as the free acid and lithium or sodium salts. The free acid of coenzyme A is detectably unstable, with around 5% degradation observed after 6 months when stored at −20 °C, and near complete degradation after 1 month at 37 °C. The lithium and sodium salts of CoA are more stable, with negligible degradation noted over several months at various temperatures. Aqueous solutions of coenzyme A are unstable above pH 8, with 31% of activity lost after 24 hours at 25 °C and pH 8\.
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In enzymology, a succinate-citramalate CoA-transferase () is an enzyme that catalyzes the chemical reaction :succinyl-CoA + citramalate \rightleftharpoons succinate + citramalyl-CoA Thus, the two substrates of this enzyme are succinyl-CoA and citramalate, whereas its two products are succinate and citramalyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is succinyl-CoA:citramalate CoA-transferase. Other names in common use include itaconate CoA-transferase, citramalate CoA-transferase, citramalate coenzyme A-transferase, and succinyl coenzyme A-citramalyl coenzyme A transferase.
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Coenzyme Q, also known as ubiquinone, is a coenzyme family that is ubiquitous in animals and most bacteria (hence the name ubiquinone). In humans, the most common form is Coenzyme Q10 or ubiquinone-10. CoQ10 is not approved by the U.S. Food and Drug Administration (FDA) for the treatment of any medical condition; however, it is sold as a dietary supplement and is an ingredient in some cosmetics. It is a 1,4-benzoquinone, where Q refers to the quinone chemical group and 10 refers to the number of isoprenyl chemical subunits in its tail.
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In 1984, Judy published clinical trial results showing that 28 of 34 patients diagnosed with congestive heart failure (NYHA class IV) had responded well to Coenzyme Q10 treatment with improved cardiac hemodynamics and kinetics. In 1985, Judy conducted a successful five-year study in Class IV congestive heart failure patients. In 1986, Judy published the first report of the long-term management of end stage heart failure with Coenzyme Q10. This study has developed into a 30-year study of the management of congestive heart failure with the ubiquinone form of Coenzyme Q10.
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It has shown that heart failure patients who received Coenzyme Q10 supplementation together with their conventional medications have a significantly better survival than patients who receive placebo supplementation together with their conventional medications. Moreover, in 1986, Judy published the results of a double- blind, crossover study of the effect of Coenzyme Q10 on patients with cardiac disease. The study data showed that improvement in cardiac pumping and contractibility came, typically, within 30 to 60 days of daily supplementation with 100 milligrams of Coenzyme Q10. Peak response came, generally, with 90 days of supplementation.
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Acyl-coenzyme A synthetase short-chain family member 2 is an enzyme that in humans is encoded by the ACSS2 gene.
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It is extractable from the stems and leaves of solanaceous species. It is notable as the biosynthetic precursor to coenzyme Q10.
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In the 1980s, Judy began to administer clinical studies of the safety and health effects of Coenzyme Q10 supplementation in humans.
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This is the enzyme which catalyses Pyruvate decarboxylation, the reaction of Pyruvate with Coenzyme A and the major entry point into the TCA cycle: :Pyruvate + Coenzyme A + NAD+ ⇒ acetyl-CoA + NADH + H+ \+ CO2 Pyruvate dehydrogenase has three chemical compartments; E1 (pyruvate decarboxylase), E2 (dihydrolipoyl transacetylase) and E3 (dihydrolipoyl dehydrogenase). Each one of the compartments has its own specific function.
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Benzyl alcohol O-benzoyltransferase (, benzoyl-CoA:benzyl alcohol benzoyltransferase, benzoyl-CoA:benzyl alcohol/phenylethanol benzoyltransferase, benzoyl-coenzyme A:benzyl alcohol benzoyltransferase, benzoyl-coenzyme A:phenylethanol benzoyltransferase) is an enzyme with systematic name benzoyl-CoA:benzyl alcohol O-benzoyltransferase. This enzyme catalyses the following chemical reaction : benzoyl-CoA + benzyl alcohol \rightleftharpoons CoA + benzyl benzoate The enzyme is involved in benzenoid and benzoic acid biosynthesis.
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Cytosolic acyl coenzyme A thioester hydrolase is an enzyme that in humans is encoded by the ACOT7 gene. This gene encodes a member of the acyl coenzyme family. The encoded protein hydrolyzes the CoA thioester of palmitoyl-CoA and other long-chain fatty acids. Decreased expression of this gene may be associated with mesial temporal lobe epilepsy.
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J. Organomet. Chem. 2001, 624, 131-135 Macromolecules such as hematin, cobalamin, vitamin B12, and coenzyme F430 are also used for dichlorination of polychlorinated ethylenes and benzenes. Charles and his co-workers reported that vitamin B12 and coenzyme F430 were capable of sequentially dechlorinating tetrachloroethene to ethene, while hematin was demonstrated to dechlorinate tetrachloroethene to vinyl chloride.
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It has been suggested that the myotoxicity of statins is due to impairment of CoQ biosynthesis, but the evidence supporting this was deemed controversial in 2011. While statins may reduce coenzyme Q10 in the blood it is unclear if they reduce coenzyme Q10 in muscle. Evidence does not support that supplementation improves side effects from statins.
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The oxidized structure of CoQ10 is shown on the top-right. The various kinds of Coenzyme Q may be distinguished by the number of isoprenoid subunits in their side-chains. The most common Coenzyme Q in human mitochondria is CoQ10. Q refers to the quinone head and 10 refers to the number of isoprene repeats in the tail.
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Butyryl-coenzyme A (or butyryl-CoA) is the coenzyme A-activated form of butyric acid. It is acted upon by butyryl-CoA dehydrogenase. It is an intermediary compound of ABE fermentation Butyryl-COA dehydrogenase Oxidation- Reduction reaction consists of 2 electron transfer with 1 proton exchange. Ideally, this will occur between pH 5.5 and 7 for optimal reaction.
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The protein encoded by this gene is an enzyme that synthesizes the prenyl side-chain of coenzyme Q, or ubiquinone, one of the key elements in the respiratory chain. The gene product catalyzes the formation of all trans-polyprenyl pyrophosphates from isopentyl diphosphate in the assembly of polyisoprenoid side chains, the first step in coenzyme Q biosynthesis.
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Statins are known to block the biological pathway that produces both cholesterol and CoQ10. Oral Coenzyme Q10 supplements replace the lost CoQ10.
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R5P and its derivatives serve as precursors to many biomolecules, including DNA, RNA, ATP, coenzyme A, FAD (Flavin adenine dinucleotide), and histidine.
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Medium-chain acyl-CoA dehydrogenase (, fatty acyl coenzyme A dehydrogenase (ambiguous), acyl coenzyme A dehydrogenase (ambiguous), acyl dehydrogenase (ambiguous), fatty-acyl-CoA dehydrogenase (ambiguous), acyl CoA dehydrogenase (ambiguous), general acyl CoA dehydrogenase (ambiguous), medium-chain acyl- coenzyme A dehydrogenase, acyl-CoA:(acceptor) 2,3-oxidoreductase (ambiguous), ACADM (gene name).) is an enzyme with systematic name medium-chain acyl- CoA:electron-transfer flavoprotein 2,3-oxidoreductase. This enzyme catalyses the following chemical reaction : a medium-chain acyl-CoA + electron-transfer flavoprotein \rightleftharpoons a medium-chain trans-2,3-dehydroacyl-CoA + reduced electron-transfer flavoprotein This enzyme contains FAD as prosthetic group.
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In enzymology, an anthranilate-CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + anthranilate + CoA \rightleftharpoons AMP + diphosphate + anthranilyl-CoA The 3 substrates of this enzyme are ATP, anthranilate, and CoA, whereas its 3 products are AMP, diphosphate, and anthranilyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is anthranilate:CoA ligase (AMP-forming). Other names in common use include anthraniloyl coenzyme A synthetase, 2-aminobenzoate-CoA ligase, 2-aminobenzoate-coenzyme A ligase, and 2-aminobenzoate coenzyme A ligase.
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3-hydroxyacyl-coenzyme A dehydrogenase deficiency is a rare condition that prevents the body from converting certain fats to energy, particularly during fasting. Normally, through a process called fatty acid oxidation, several enzymes work in a step-wise fashion to metabolize fats and convert them to energy. People with 3-hydroxyacyl-coenzyme A dehydrogenase deficiency have inadequate levels of an enzyme required for a step that metabolizes groups of fats called medium chain fatty acids and short chain fatty acids; for this reason this disorder is sometimes called medium- and short-chain 3-hydroxyacyl-coenzyme A dehydrogenase (M/SCHAD) deficiency.
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In 2007, Judy wrote a seminal paper about the crystalline Coenzyme Q10 raw material. He emphasized the need for the crystals to be dissociated into single free molecules to be absorbed, and he discussed the simple passive facilitated diffusion process by which the molecules can be absorbed in the small intestines. He explained the transport of the fat-soluble Coenzyme Q10 molecules, their conversion from the oxidized form, ubiquinone, to the reduced form, ubiquinol, and the importance of the supplement formulation for the bio- availability of Coenzyme Q10. He concluded by elucidating the biological functions of the ubiquinone and ubiquinol molecules.
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Enoyl Coenzyme A hydratase, short chain, 1, mitochondrial, also known as ECHS1, is a human gene. The protein encoded by this gene functions in the second step of the mitochondrial fatty acid beta-oxidation pathway. It catalyzes the hydration of 2-trans-enoyl-coenzyme A (CoA) intermediates to L-3-hydroxyacyl-CoAs. The gene product is a member of the hydratase/isomerase superfamily.
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NAD(P)(H) can bind to a second site on each subunit. This site binds NAD(H) ~ 10-fold better than NADP(H) with the reduced forms better than the oxidized forms. Although it has been suggested that binding of the reduced coenzyme at this site inhibits the reaction, while oxidized coenzyme binding causes activation, the effect is still unclear.
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These group-transfer intermediates are called coenzymes. Each class of group-transfer reactions is carried out by a particular coenzyme, which is the substrate for a set of enzymes that produce it, and a set of enzymes that consume it. These coenzymes are therefore continuously made, consumed and then recycled. One central coenzyme is adenosine triphosphate (ATP), the universal energy currency of cells.
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Isobutyryl-coenzyme A dehydrogenase deficiency has an autosomal recessive pattern of inheritance. Defects in the ACAD8 gene cause isobutyryl-coenzyme A dehydrogenase deficiency. The ACAD8 gene provides instructions for making an enzyme that plays an essential role in breaking down proteins from the diet. Specifically, the enzyme is responsible for processing valine, an amino acid that is part of many proteins.
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3-hydroxybenzoate—CoA ligase (, 3-hydroxybenzoyl-CoA synthetase, 3-hydroxybenzoate-coenzyme A ligase (AMP-forming), 3-hydroxybenzoyl coenzyme A synthetase, 3-hydroxybenzoyl-CoA ligase) is an enzyme with systematic name 3-hydroxybenzoate:CoA ligase (AMP-forming). This enzyme catalyses the following chemical reaction : ATP + 3-hydroxybenzoate + CoA \rightleftharpoons AMP + diphosphate + 3-hydroxybenzoyl-CoA The enzyme works equally well with 4-hydroxybenzoate.
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Adrenodoxin reductase is a flavoprotein as it carries a FAD type coenzyme. The enzyme functions as the first electron transfer protein of mitochondrial P450 systems such as P450scc. The FAD coenzyme receives two electrons from NADPH and transfers them one at a time to the electron transfer protein adrenodoxin. Adrenodoxin functions as a mobile shuttle that transfers electrons between ADXR and mitochondrial P450s.
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This latter domain determines the substrate specificity and contains amino acids involved in catalysis. Little sequence similarity has been found in the coenzyme binding domain although there is a large degree of structural similarity, and it has therefore been suggested that the structure of dehydrogenases has arisen through gene fusion of a common ancestral coenzyme nucleotide sequence with various substrate specific domains.
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Ubiquinone biosynthesis protein COQ9, mitochondrial, also known as coenzyme Q9 homolog (COQ9), is a protein that in humans is encoded by the COQ9 gene.
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In 1998, Judy reported the results of a study of Coenzyme Q10 supplementation of chronic fatigue syndrome patients. Two groups of patients, similar in age, exercise tolerance, and duration of illness were given 100 milligrams and 300 milligrams of Coenzyme Q10, respectively. 60% of the patients in the 100-milligram group responded to the treatment; 91% of the patients in the 300-milligram group responded. In the non-responders, the blood and tissue CoQ10 levels did increase with the supplementation but not to the extent that they increased in the responders. The average time to a discernible change in exercise tolerance and recovery time was 30 days in the group of patients who took 300 milligrams of Coenzyme Q10 daily and 60 days in the group of patients that took 100 milligrams of Coenzyme Q10 daily.
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Sterol O-acyltransferase (acyl-Coenzyme A: cholesterol acyltransferase) 1, also known as SOAT1, is an enzyme that in humans is encoded by the SOAT1 gene.
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When there is excess glucose, coenzyme A is used in the cytosol for synthesis of fatty acids. This process is implemented by regulation of acetyl-CoA carboxylase, which catalyzes the committed step in fatty acid synthesis. Insulin stimulates acetyl-CoA carboxylase, while epinephrine and glucagon inhibit its activity. During cell starvation, coenzyme A is synthesized and transports fatty acids in the cytosol to the mitochondria.
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NAD+ kinase (EC 2.7.1.23, NADK) is an enzyme that converts nicotinamide adenine dinucleotide (NAD+) into NADP+ through phosphorylating the NAD+ coenzyme. NADP+ is an essential coenzyme that is reduced to NADPH primarily by the pentose phosphate pathway to provide reducing power in biosynthetic processes such as fatty acid biosynthesis and nucleotide synthesis. The structure of the NADK from the archaean Archaeoglobus fulgidus has been determined.
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Judy and the SIBR Research group have supplemented several Parkinson's patients with Coenzyme Q10 in the period from 1995 to 2019. Coenzyme Q10 supplementation has been found to decrease the progression of Parkinson's disease in early-onset Parkinson's disease but not in patients with full-blown disabling disease. Many of these early-onset disease patients have been functional for as many as 24 years [1 p 135].
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All of the patients continued their standard heart failure medications. Not until the end of the clinical trial did the researchers and the patients find out which patients were receiving the active Coenzyme Q10 treatment and which patients were receiving the placebo treatment. The patients in the Coenzyme Q10 treatment group had significantly reduced risk of heart disease death and death from all causes and significantly fewer hospital stays for heart failure complications. A later sub-analysis including only the European segment of the Q-Symbio Study showed that the Coenzyme Q10 therapy was also positively associated with a significant improvement in ejection fraction.
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ACADM (acyl-Coenzyme A dehydrogenase, C-4 to C-12 straight chain) is a gene that provides instructions for making an enzyme called acyl-coenzyme A dehydrogenase that is important for breaking down (degrading) a certain group of fats called medium-chain fatty acids. These fatty acids are found in foods such as milk and certain oils, and they are also stored in the body's fat tissue. Medium-chain fatty acids are also produced when larger fatty acids are degraded. The acyl-coenzyme A dehydrogenase for medium-chain fatty acids (ACADM) enzyme is essential for converting these particular fatty acids to energy, especially during periods without food (fasting).
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In enzymology, a CoA-glutathione reductase () is an enzyme that catalyzes the chemical reaction :CoA + glutathione + NADP+ \rightleftharpoons CoA- glutathione + NADPH + H+ The 3 substrates of this enzyme are CoA, glutathione, and NADP+, whereas its 3 products are CoA-glutathione, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is glutathione:NADP+ oxidoreductase (CoA-acylating). Other names in common use include coenzyme A glutathione disulfide reductase, NADPH-dependent coenzyme A-SS-glutathione reductase, coenzyme A disulfide- glutathione reductase, and NADPH:CoA-glutathione oxidoreductase. This enzyme participates in cysteine metabolism.
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In 1968, Judy met Dr. Karl Folkers, the chemist who had determined the structure of the Coenzyme Q10 molecule in 1958 while Dr. Folkers was working at the Merck Research Laboratories in New Jersey. By 1968, Dr. Folkers had established the Institute for Bio-Medical Research at the University of Texas in Austin. The purpose of the new institute was to increase the understanding of the importance of the substance Coenzyme Q10 to human health. Dr. Folkers encouraged Judy to do, first, preclinical studies of Coenzyme Q10 absorption and bio-availability using live dogs, which were not put to sleep during the experiments and were not sacrificed after the experiments.
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Acetyl-coenzyme A transporter 1 also known as solute carrier family 33 member 1 (SLC33A1) is a protein that in humans is encoded by the SLC33A1 gene.
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Other names in common use include anthraniloyl coenzyme A reductase, and 2-aminobenzoyl- CoA monooxygenase/reductase. This enzyme participates in carbazole degradation. It employs one cofactor, FAD.
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Taking Coenzyme Q10 for the past 20 years has improved his heart function, and he has had a very productive and healthy life since the heart attack.
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Initially, Lynen found that acetate activated by Coenzyme A was needed to start the process. He discovered the chemical structure of acetyl-coenzyme A, which was needed for a detailed understanding of the biochemical pathways. He also learned that biotin, or Vitamin B7, was needed for in the process. Lynen with family in Stockholm in 1964 On 14 May 1937, Lynen married Eva Wieland (1915–2002), daughter of his academic teacher.
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Since coenzyme A is, in chemical terms, a thiol, it can react with carboxylic acids to form thioesters, thus functioning as an acyl group carrier. It assists in transferring fatty acids from the cytoplasm to mitochondria. A molecule of coenzyme A carrying an acyl group is also referred to as acyl-CoA. When it is not attached to an acyl group, it is usually referred to as 'CoASH' or 'HSCoA'.
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This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is acyl- CoA:NADP+ cis-2-oxidoreductase. Other names in common use include NADPH- dependent cis-enoyl-CoA reductase, reductase, cis-2-enoyl coenzyme A, cis-2-enoyl-coenzyme A reductase, and cis-2-enoyl-CoA reductase (NADPH).
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The ability of GRHPR to reduce glyoxylate to glycolate is found in other glycerate dehydrogenase homologs as well. This is important for the intracellular regulation of glyoxylate levels, which has important medical ramifications. As mentioned earlier, these enzymes have the ability to use either NADH or NADPH as the coenzyme. This gives them an advantage over other enzymes that can only use a single form of the coenzyme.
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Other names in common use include caffeoyl coenzyme A methyltransferase, caffeoyl-CoA 3-O-methyltransferase, and trans-caffeoyl-CoA 3-O-methyltransferase. This enzyme participates in phenylpropanoid biosynthesis.
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MupH is a Hydroxymethylglutaryl-Coenzyme A synthase, MupJ and MupK are Enoyl-CoA hydratases. Figure 4. The pyran ring of mupirocin is generated in this proposed multistep reaction.
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Nicotinamide adenine dinucleotide phosphate is a coenzyme present in redox and biosynthetic reactions. The domain binds NADP in its oxidised or reduced forms as NADP+ or NADPH respectively.
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This enzyme takes of the Acyl-CoA to form a free fatty acid and coenzyme A, in other words deactivates the fatty acid by breaking down Acyl-CoA.
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In molecular biology, the citrate synthase family of proteins includes the enzymes citrate synthase , and the related enzymes 2-methylcitrate synthase and ATP citrate lyase . Citrate synthase is a member of a small family of enzymes that can directly form a carbon-carbon bond without the presence of metal ion cofactors. It catalyses the first reaction in the Krebs' cycle, namely the conversion of oxaloacetate and acetyl-coenzyme A into citrate and coenzyme A. This reaction is important for energy generation and for carbon assimilation. The reaction proceeds via a non-covalently bound citryl-coenzyme A intermediate in a 2-step process (aldol-Claisen condensation followed by the hydrolysis of citryl-CoA).
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600px 4-coumaroyl-CoA and three units of malonyl-CoA are converted into three molecules of carbon dioxide, four molecules of coenzyme A and one unit of naringenin chalcone.
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This gene encodes the enzyme that catalyzes adenylation of flavin mononucleotide (FMN) to form flavin adenine dinucleotide (FAD) coenzyme. Alternatively spliced transcript variants encoding distinct isoforms have been observed.
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Coenzyme A is one of five crucial coenzymes that are necessary in the reaction mechanism of the citric acid cycle. Its acetyl- coenzyme A form is the primary input in the citric acid cycle and is obtained from glycolysis, amino acid metabolism, and fatty acid beta oxidation. This process is the body's primary catabolic pathway and is essential in breaking down the building blocks of the cell such as carbohydrates, amino acids, and lipids.
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The systematic name for the MenE enzyme is 2-succinylbenzoate: CoA ligase (AMP-forming). Other names for this enzyme include: o-succinylbenzoate-CoA synthase; o-succinylbenzoyl-coenzyme A synthetase; OSB-CoA synthetase; OSB: CoA ligase; synthetase, and o-succinylbenzoyle coenzyme A. The EC number is 6.2.1.26. MenE belongs to the ligase enzyme family, or class 6. In the presence of 0.5mM of Ca(2+), K(+), Na(+), and Zn(2+) the enzyme activity was increased twofold.
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Medium-chain acyl-coenzyme A dehydrogenase deficiency can be caused by mutations in the ACADM gene. More than 30 ACADM gene mutations that cause medium-chain acyl-coenzyme A dehydrogenase deficiency have been identified. Many of these mutations switch an amino acid building block in the ACADM enzyme. The most common amino acid substitution replaces lysine with glutamic acid at position 329 in the enzyme's chain of amino acids (also written as Lys329Glu or K329E).
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Many contain the nucleotide adenosine monophosphate (AMP) as part of their structures, such as ATP, coenzyme A, FAD, and NAD+. This common structure may reflect a common evolutionary origin as part of ribozymes in an ancient RNA world. It has been suggested that the AMP part of the molecule can be considered to be a kind of "handle" by which the enzyme can "grasp" the coenzyme to switch it between different catalytic centers.
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Nicotinamide adenine dinucleotide (NAD+), a derivative of vitamin B3 (niacin), is an important coenzyme that acts as a hydrogen acceptor. Hundreds of separate types of dehydrogenases remove electrons from their substrates and reduce NAD+ into NADH. This reduced form of the coenzyme is then a substrate for any of the reductases in the cell that need to reduce their substrates. Nicotinamide adenine dinucleotide exists in two related forms in the cell, NADH and NADPH.
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Other names in common use include acetoacetyl-CoA thiolase, beta-acetoacetyl coenzyme A thiolase, 2-methylacetoacetyl-CoA thiolase [misleading], 3-oxothiolase, acetyl coenzyme A thiolase, acetyl-CoA acetyltransferase, acetyl-CoA:N-acetyltransferase, and thiolase II. This enzyme participates in 10 metabolic pathways: fatty acid metabolism, synthesis and degradation of ketone bodies, valine, leucine and isoleucine degradation, lysine degradation, tryptophan metabolism, pyruvate metabolism, benzoate degradation via coa ligation, propanoate metabolism, butanoate metabolism, and two-component system - general.
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N-Formylmethanofuran donates the C1 group to the N5 site of the pterin to give the formyl- THMPT. The formyl group subsequently condenses intramolecularly to give methenyl- , which is then reduced to methylene- THMPT. Methylene- MPT is subsequently converted, using coenzyme F420 as the electron source, to methyl- THMPT, catalyzed by F420-dependent methylene- THMPT reductase. Methyl- THMPT is the methyl donor to coenzyme M, a conversion mediated by methyl- THMPT:coenzyme M methyl-transferase.
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This malyl-CoA intermediate then undergoes hydrolysis at the acyl-CoA portion, replacing it with a carboxylate anion. The enzyme is free to release the malate and the coenzyme A molecules.
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In enzymology, a Hydroxymethylglutaryl-CoA reductase () is an enzyme that catalyzes the chemical reaction : (R)-mevalonate + CoA + 2 NAD+ \rightleftharpoons 3-hydroxy-3-methylglutaryl-CoA + 2 NADH + 2 H+ The 3 substrates of this enzyme are (R)-mevalonate, CoA, and NAD+, whereas its 3 products are 3-hydroxy-3-methylglutaryl-CoA, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (R)-mevalonate:NAD+ oxidoreductase (CoA-acylating). Other names in common use include beta-hydroxy-beta-methylglutaryl coenzyme A reductase, beta-hydroxy-beta-methylglutaryl CoA-reductase, 3-hydroxy-3-methylglutaryl coenzyme A reductase, and hydroxymethylglutaryl coenzyme A reductase.
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In comparison to N-demthylases, another class of caffeine-degrading enzymes, caffeine dehydrogenase does not require the use of oxygen, NAD, or NADP as electron acceptors. Instead, caffeine dehydrogenase uses dichlorophenol, indophenol, coenzyme Q0, and cytochrome c as electron acceptors. Caffeine dehydrogenase has been noted as being more stable as well. Caffeine dehydrogenase is responsible for catalyzing the oxidation of caffeine directly into trimethyluric acid, and the enzyme uses coenzyme Q0, also known as ubiquinone, as an electron acceptor.
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Very long-chain specific acyl-CoA dehydrogenase, mitochondrial (VLCAD) is an enzyme that in humans is encoded by the ACADVL gene. Mutations in the ACADVL are associated with very long-chain acyl-coenzyme A dehydrogenase deficiency. The protein encoded by this gene is targeted to the inner mitochondrial membrane, where it catalyzes the first step of the mitochondrial fatty acid beta-oxidation pathway. This acyl-Coenzyme A dehydrogenase is specific to long-chain and very-long-chain fatty acids.
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These discoveries led to Krebs being awarded the Nobel Prize in physiology in 1953, which was shared with the German biochemist Fritz Albert Lipmann who also codiscovered the essential cofactor coenzyme A.
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Simplified mechanism for pyruvate dehydrogenase reaction. The TPP coenzyme is shown with abbreviated substituents. The thiamine pyrophosphate (TPP) converts to an ylide by deprotonation. The ylide attack the ketone group of pyruvate.
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The molecule below has three isoprenoid units and would be called Q3. :alt=Coenzyme Q3 In its pure state, it is an orange-coloured lipophile powder, and has no taste nor odour.
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Crotonyl-coenzyme A is an intermediate in the fermentation of butyric acid, and in the metabolism of lysine and tryptophan. It is important in the metabolism of fatty acids and amino acids.
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PLP aids in the synthesis of hemoglobin, by serving as a coenzyme for the enzyme ALA synthase. It also binds to two sites on hemoglobin to enhance the oxygen binding of hemoglobin.
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PLP is a required coenzyme of glycogen phosphorylase, the enzyme necessary for glycogenolysis to occur. PLP can catalyze transamination reactions that are essential for providing amino acids as a substrate for gluconeogenesis.
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Pyruvate dehydrogenase (EC 1.2.4.1) is responsible for the oxidation of pyruvate, dihydrolipoyl transacetylase (this enzyme; EC 2.3.1.12) transfers the acetyl group to coenzyme A (CoA), and dihydrolipoyl dehydrogenase (EC 1.8.1.4) regenerates the lipoamide.
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Propionyl-CoA is a coenzyme A derivative of propionic acid. It is composed of a 24 total carbon chain (without the coenzyme, it is a 3 carbon structure) and its production and metabolic fate depend on which organism it is present in. Several different pathways can lead to its production, such as through the catabolism of specific amino acids or the oxidation of odd-chain fatty acids. It later can be broken down by propionyl-CoA carboxylase or through the methylcitrate cycle.
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In enzymology, a succinyl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :succinyl-CoA + H2O \rightleftharpoons CoA + succinate Thus, the two substrates of this enzyme are succinyl-CoA and H2O, whereas its two products are CoA and succinate. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is succinyl-CoA hydrolase. Other names in common use include succinyl-CoA acylase, succinyl coenzyme A hydrolase, and succinyl coenzyme A deacylase.
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In enzymology, an acetoacetyl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :acetoacetyl-CoA + H2O \rightleftharpoons CoA + acetoacetate Thus, the two substrates of this enzyme are acetoacetyl-CoA and H2O, whereas its two products are CoA and acetoacetate. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is acetoacetyl-CoA hydrolase. Other names in common use include acetoacetyl coenzyme A hydrolase, acetoacetyl CoA deacylase, and acetoacetyl coenzyme A deacylase.
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The reaction can be extended to aliphatic aldehydes with base catalysis in the presence of thiazolium salts; the reaction mechanism is essentially the same... These compounds are important in the synthesis of heterocyclic compounds. The analogous 1,4-addition of an aldehyde to an enone is called the Stetter reaction. In biochemistry, the coenzyme thiamine is responsible for biosynthesis of acyloin-like compounds utilizing the benzoin addition. This coenzyme also contains a thiazolium moiety, which on deprotonation becomes a nucleophilic carbene.
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His proposed treatments include giving patients supplemental doses of substances that occur naturally in the body which he believes enhance metabolic reactions in cells. Sinatra believes coenzyme Q10, D-ribose, and L-carnitine is important in this proposed process because of the roles they play in the production and use of adenosine triphosphate (ATP), the body’s basic cellular fuel. In this context, he has called coenzyme Q10 a “wonder nutrient,” especially for women, as he believes it helps the heart pump more effectively.
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Vitamin B1, also known as thiamine, is a coenzyme essential for the metabolism of carbohydrates. This vitamin is important for the facilitation of glucose use, thus ensuring the production of energy for the brain, and normal functioning of the nervous system, muscles, and heart. Thiamine is found in all living tissues, and is uniformly distributed throughout mammalian nervous tissue, including the brain and spinal cord. Metabolism and coenzyme function of the vitamin suggest a distinctive function for thiamin within the nervous system.
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Perhaps with future techniques of promoting muscle cell regeneration and satellite cell proliferation, functional status in KSS patients could be greatly improved. One study described a patient with KSS who had reduced serum levels of coenzyme Q10. Administration of 60–120 mg of Coenzyme Q10 for 3 months resulted in normalization of lactate and pyruvate levels, improvement of previously diagnosed first degree AV block, and improvement of ocular movements. A screening ECG is recommended in all patients presenting with CPEO.
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The degradation of L-threonine to glycine consists of a two-step biochemical pathway involving the enzymes L-threonine dehydrogenase and 2-amino-3-ketobutyrate coenzyme A ligase. L-Threonine is first converted into 2-amino-3-ketobutyrate by L-threonine dehydrogenase. This gene encodes the second enzyme in this pathway, which then catalyzes the reaction between 2-amino-3-ketobutyrate and coenzyme A to form glycine and acetyl-CoA. The encoded enzyme is considered a class II pyridoxal-phosphate-dependent aminotransferase.
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He has also done extensive study of the absorption and bio-availability of various formulations of Coenzyme Q10 supplements. In 1995, Judy founded the SIBR Research Institute, of which he is the president. The SIBR Research Institute helps develop clinical trial protocols to test the safety and efficacy of natural products. It is a full-service clinical research institute. Judy is the author of numerous scholarly journal articles, college textbooks, and the book The Substance That Powers Life: Coenzyme Q10, An Insider’s Guide.
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It has been shown that these proteins are homodimeric enzymes. This means that 2 identical proteins are linked forming one larger complex. The active site is found in each subunit between the two distinct α/β/α globular domains, the substrate binding domain and the coenzyme binding domain. This coenzyme binding domain is slightly larger than the substrate binding domain and contains a NAD(P) Rossmann fold along with the "dimerisation loop" which holds the two subunits of the homodimer together.
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Cholate—CoA ligase (, BAL, bile acid CoA ligase, bile acid coenzyme A ligase, choloyl-CoA synthetase, choloyl coenzyme A synthetase, cholic thiokinase, cholate thiokinase, cholic acid:CoA ligase, 3alpha,7alpha,12alpha- trihydroxy-5beta-cholestanoyl coenzyme A synthetase, 3alpha,7alpha,12alpha- trihydroxy-5beta-cholestanoate-CoA ligase, 3alpha,7alpha,12alpha- trihydroxy-5beta-cholestanoate-CoA synthetase, THCA-CoA ligase, 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanate—CoA ligase, 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanate:CoA ligase (AMP-forming), cholyl-CoA synthetase, trihydroxycoprostanoyl-CoA synthetase) is an enzyme with systematic name cholate:CoA ligase (AMP-forming). This enzyme catalyses the following chemical reaction : (1) ATP + cholate + CoA \rightleftharpoons AMP + diphosphate + choloyl-CoA : (2) ATP + (25R)-3alpha,7alpha,12alpha- trihydroxy-5beta-cholestan-26-oate + CoA \rightleftharpoons AMP + diphosphate + (25R)-3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoyl-CoA This enzyme requires Mg2+ for activity.
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Acyl-coenzyme A thioesterase 12 or StAR-related lipid transfer protein 15 (STARD15) is an enzyme that in humans is encoded by the ACOT12 gene. The protein contains a StAR-related lipid transfer domain.
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Coenzyme-B sulfoethylthiotransferase is a multiprotein complex made up of a pair of identical halves. Each half is made up of three subunits: α, β and γ, also called McrA, McrB and McrG, respectively.
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Mutations in this gene are associated with autosomal recessive coenzyme Q10 deficiency-6 (COQ10D6), which manifests as nephrotic syndrome with sensorineural deafness. Alternatively spliced transcript variants encoding different isoforms have been described for this gene.
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The patients in the Coenzyme Q10 adjunctive treatment group had significantly fewer major adverse cardiovascular events, significantly reduced risk of cardiovascular death and all-cause death, and significantly fewer hospital stays for heart failure complications.
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When the thiamine pyrophosphatase (TPP) coenzyme is bound, the rates of phosphorylation by all four isozymes are drastically affected; specifically, the incorporation of phosphate groups by PDK1 into sites 2 and 3 is significantly reduced.
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Coumaroyl-coenzyme A is a central intermediate in the biosynthesis of myriad natural products found in plants. These products include lignols (precursors to lignin and lignocellulose), flavonoids, isoflavonoids, coumarins, aurones, stilbenes, catechin, and other phenylpropanoids.
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In enzymology, a butyrate-acetoacetate CoA-transferase () is an enzyme that catalyzes the chemical reaction :butanoyl-CoA + acetoacetate \rightleftharpoons butanoate + acetoacetyl-CoA Thus, the two substrates of this enzyme are butanoyl-CoA and acetoacetate, whereas its two products are butanoate and acetoacetyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is butanoyl-CoA:acetoacetate CoA-transferase. Other names in common use include butyryl coenzyme A-acetoacetate coenzyme A-transferase, and butyryl-CoA-acetoacetate CoA-transferase.
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The reaction is easily reversible, when NADH reduces another molecule and is re-oxidized to NAD. This means the coenzyme can continuously cycle between the NAD and NADH forms without being consumed. In appearance, all forms of this coenzyme are white amorphous powders that are hygroscopic and highly water-soluble. The solids are stable if stored dry and in the dark. Solutions of NAD are colorless and stable for about a week at 4 °C and neutral pH, but decompose rapidly in acids or alkalis.
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In enzymology, a vinylacetyl-CoA Delta-isomerase () is an enzyme that catalyzes the chemical reaction :vinylacetyl-CoA \rightleftharpoons crotonyl- CoA Hence, this enzyme has one substrate, vinylacetyl-CoA, and one product, crotonyl-CoA. This enzyme belongs to the family of isomerases, specifically those intramolecular oxidoreductases transposing C=C bonds. The systematic name of this enzyme class is vinylacetyl-CoA Delta3-Delta2-isomerase. Other names in common use include vinylacetyl coenzyme A Delta-isomerase, vinylacetyl coenzyme A isomerase, and Delta3-cis-Delta2-trans-enoyl-CoA isomerase.
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This gene encodes an enzyme (cob(I)yrinic acid a,c-diamide adenosyltransferase) that catalyzes the final step in the conversion of vitamin B12 into adenosylcobalamin (AdoCbl), a vitamin B12-containing coenzyme for methylmalonyl-CoA mutase.
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Capping with NAD+, NADH, or 3′-dephospho-coenzyme A occurs only at promoters that have certain sequences at and immediately upstream of the transcription start site and therefore occurs only for RNAs synthesized from certain promoters.
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Phosphopantetheine, also known as 4'-Phosphopantetheine, is an essential prosthetic group of acyl carrier protein (ACP) and peptidyl carrier proteins (PCP) and aryl carrier proteins (ArCP) derived from Coenzyme A. It is also present in formyltetrahydrofolate dehydrogenase.
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AICAR transformylase requires the coenzyme N10-formyltetrahydrofolate (N10-formyl- THF) as the formyl donor for the formylation of AICAR to FAICAR. However, AICAR transformylase and GAR transformylase do not share a high sequence similarity or structural homology.
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In enzymology, a choloyl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :choloyl-CoA + H2O \rightleftharpoons cholate + CoA Thus, the two substrates of this enzyme are choloyl-CoA and H2O, whereas its two products are cholate and CoA. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is choloyl-CoA hydrolase. Other names in common use include PTE-2 (ambiguous), choloyl-coenzyme A thioesterase, chenodeoxycholoyl-coenzyme A thioesterase, and peroxisomal acyl-CoA thioesterase 2.
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In enzymology, an acyl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :acyl-CoA + H2O \rightleftharpoons CoA + a carboxylate Thus, the two substrates of this enzyme are acyl-CoA and H2O, whereas its two products are CoA and carboxylate. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is acyl-CoA hydrolase. Other names in common use include acyl coenzyme A thioesterase, acyl-CoA thioesterase, acyl coenzyme A hydrolase, thioesterase B, thioesterase II, and acyl-CoA thioesterase.
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Decaprenyl-diphosphate synthase subunit 1 is an enzyme that in humans is encoded by the PDSS1 gene. The protein encoded by this gene is an enzyme that elongates the prenyl side-chain of coenzyme Q, or ubiquinone, one of the key elements in the respiratory chain. The gene product catalyzes the formation of all trans-polyprenyl pyrophosphates from isopentyl diphosphate in the assembly of polyisoprenoid side chains, the first step in coenzyme Q biosynthesis. The protein may be peripherally associated with the inner mitochondrial membrane, though no transit peptide has been definitively identified to date.
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In enzymology, an acetate CoA-transferase () is an enzyme that catalyzes the chemical reaction :acyl-CoA + acetate \rightleftharpoons a fatty acid anion + acetyl-CoA Thus, the two substrates of this enzyme are acyl-CoA and acetate, whereas its two products are fatty acid anion and acetyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is acyl-CoA:acetate CoA-transferase. Other names in common use include acetate coenzyme A-transferase, butyryl CoA:acetate CoA transferase, butyryl coenzyme A transferase, and succinyl- CoA:acetate CoA transferase.
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Many cofactors (non-protein-based helper molecules) feature thiols. The biosynthesis and degradation of fatty acids and related long-chain hydrocarbons is conducted on a scaffold that anchors the growing chain through a thioester derived from the thiol Coenzyme A. The biosynthesis of methane, the principal hydrocarbon on Earth, arises from the reaction mediated by coenzyme M, 2-mercaptoethyl sulfonic acid. Thiolates, the conjugate bases derived from thiols, form strong complexes with many metal ions, especially those classified as soft. The stability of metal thiolates parallels that of the corresponding sulfide minerals.
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In enzymology, a benzoate-CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + benzoate + CoA \rightleftharpoons AMP + diphosphate + benzoyl-CoA The 3 substrates of this enzyme are ATP, benzoate, and CoA, whereas its 3 products are AMP, diphosphate, and benzoyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is benzoate:CoA ligase (AMP-forming). Other names in common use include benzoate- coenzyme A ligase, benzoyl-coenzyme A synthetase, and benzoyl CoA synthetase (AMP forming).
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Immunoaffinity media (detailed below) utilizes antigens' and antibodies' high specificity to separate; immobilized metal affinity chromatography is detailed further below and uses interactions between metal ions and proteins (usually specially tagged) to separate; nucleotide/coenzyme that works to separate dehydrogenases, kinases, and transaminases. Nucleic acids function to trap mRNA, DNA, rRNA, and other nucleic acids/oligonucleotides. Protein A/G method is used to purify immunoglobulins. Speciality media are designed for a specific class or type of protein/co enzyme; this type of media will only work to separate a specific protein or coenzyme.
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2-phospho-L-lactate transferase (, LPPG:Fo 2-phospho-L-lactate transferase, LPPG:7,8-didemethyl-8-hydroxy-5-deazariboflavin 2-phospho-L-lactate transferase, MJ1256, lactyl-2-diphospho-(5')guanosine:Fo 2-phospho-L-lactate transferase, CofD) is an enzyme with systematic name (2S)-lactyl-2-diphospho-5'-guanosine:7,8-didemethyl-8-hydroxy-5-deazariboflavin 2-phospho-L-lactate transferase. This enzyme catalyses the following chemical reaction : (2S)-lactyl-2-diphospho-5'-guanosine + 7,8-didemethyl-8-hydroxy-5-deazariboflavin \rightleftharpoons GMP + coenzyme F420-0 This enzyme is involved in the biosynthesis of coenzyme F420.
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The main role of NAD in metabolism is the transfer of electrons from one molecule to another. Reactions of this type are catalyzed by a large group of enzymes called oxidoreductases. The correct names for these enzymes contain the names of both their substrates: for example NADH-ubiquinone oxidoreductase catalyzes the oxidation of NADH by coenzyme Q. However, these enzymes are also referred to as dehydrogenases or reductases, with NADH-ubiquinone oxidoreductase commonly being called NADH dehydrogenase or sometimes coenzyme Q reductase. There are many different superfamilies of enzymes that bind NAD / NADH.
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Erucic acid is produced by elongation of oleic acid via oleoyl-coenzyme A and malonyl-CoA. Erucic acid is broken down into shorter- chain fatty acids in the human liver by the long-chain acyl CoA dehydrogenase enzyme.
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Some are more commonly recognized by name than by number: niacin, pantothenic acid, biotin and folate. Each B vitamin is either a cofactor (generally a coenzyme) for key metabolic processes or is a precursor needed to make one.
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Campbell can be heard every weekend on stations all throughout the US, as host of Health Line, a series of informercials hosted by Purity Products. Campbell assists in promoting Purity's various fish oil, vitamin D, and coenzyme q10 products.
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This condition is sometimes mistaken for fatty acid and ketogenesis disorders such as Medium-chain acyl-coenzyme A dehydrogenase deficiency (MCAD), other long-chain fatty acid oxidation disorders such as Carnitine palmitoyltransferase II deficiency (CPT-II) and Reye syndrome.
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When the thiamine pyrophosphate (TPP) coenzyme is bound, the rates of phosphorylation by all four isozymes are drastically affected. Site 1 is the most affected, with the rate being significantly decreased. However, overall activity by PDK4 is not affected.
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The protein encoded by this gene is involved in the translocation of cobalamin into the mitochondrion, where it is used in the final steps of adenosylcobalamin synthesis. Adenosylcobalamin is a coenzyme required for the activity of methylmalonyl-CoA mutase.
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Complex III is required for the catalysis of electron transfer from coenzyme Q to cytochrome c as well as the pumping of protons into the inner membrane from the matrix for the generation of an ATP-coupled electrochemical potential.
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The enzyme's action can be inhibited by the coenzyme A-conjugate of bempedoic acid, a compound which lowers LDL cholesterol in humans. The drug was approved by the Food and Drug Administration in February 2020 for use in the United States.
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Methylated-thiol-coenzyme M methyltransferase (, mtsA (gene)) is an enzyme with systematic name methylated-thiol:coenzyme M methyltransferase. This enzyme catalyses the following chemical reaction: This enzyme involved in methanogenesis from methylated thiols, such as methanethiol, dimethyl sulfide, and 3-S-methylmercaptopropionate.
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Several clinical trials of new experimental treatments are underway and planned in Huntington's disease. Compounds that have failed to prevent or slow progression of Huntington's disease in human trials include remacemide, coenzyme Q10, riluzole, creatine, minocycline, ethyl-EPA, phenylbutyrate and dimebon.
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This complex is devoid of coenzyme activity and SDH is not able to function (See Enzyme Mechanism Section). In general, homocysteine is an amino acid and metabolite of methionine; increased levels of homocysteine can lead to homocystinuria(see section Disease Relevance).
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In biochemistry, the best-known thioesters are derivatives of coenzyme A, e.g., acetyl-CoA.Matthys J. Janssen "Carboxylic Acids and Esters" in PATAI's Chemistry of Functional Groups: Carboxylic Acids and Esters, Saul Patai, Ed. John Wiley, 1969, New York: pp. 705–764.
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3-Nitrooxypropanol, abbreviated 3NOP, is an organic compound with the formula HOCH2CH2CH2ONO2. It is the mononitrate ester of 1,3-propanediol. The compound is an inhibitor of the enzyme methyl coenzyme M reductase (MCR). MCR catalyzes the final step in methanogenesis.
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The centers of these rings are not selective, thus allowing the variety of metal ions to be incorporated. Mg porphyrin gives rise to chlorophyll, Fe porphyrin to heme proteins, Ni porphyrin yields factor F-430, and Co porphyrin Coenzyme B12.
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In enzymology, a 3-hydroxybutyryl-CoA dehydratase () is an enzyme that catalyzes the chemical reaction :(3R)-3-hydroxybutanoyl-CoA \rightleftharpoons crotonoyl-CoA + H2O Hence, this enzyme has one substrate, (3R)-3-hydroxybutanoyl-CoA, and two products, crotonoyl-CoA and H2O. This enzyme belongs to the family of lyases, specifically the hydro-lyases, which cleave carbon-oxygen bonds. The systematic name of this enzyme class is (3R)-3-hydroxybutanoyl-CoA hydro-lyase (crotonoyl-CoA-forming). Other names in common use include D-3-hydroxybutyryl coenzyme A dehydratase, D-3-hydroxybutyryl-CoA dehydratase, enoyl coenzyme A hydrase (D), and (3R)-3-hydroxybutanoyl-CoA hydro-lyase.
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Another way that enzymes can exist in inactive forms and later be converted to active forms is by activating only when a cofactor, called a coenzyme, is bound. In this system, the inactive form (the apoenzyme) becomes the active form (the holoenzyme) when the coenzyme binds. In the duodenum, the pancreatic zymogens, trypsinogen, chymotrypsinogen, proelastase and procarboxypeptidase are converted into active enzymes by enteropeptidase and trypsin. Chymotrypsinogen, is single polypeptide chain of 245 amino acids residues, is converted to alpha-chymotrypsin, which has three polypeptide chains linked by two of the five disulfide bond present in the primary structure of chymotrypsinogen.
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Long-chain acyl-CoA dehydrogenase (, palmitoyl-CoA dehydrogenase, palmitoyl- coenzyme A dehydrogenase, long-chain acyl-coenzyme A dehydrogenase, long- chain-acyl-CoA:(acceptor) 2,3-oxidoreductase, ACADL (gene).) is an enzyme with systematic name long-chain acyl-CoA:electron-transfer flavoprotein 2,3-oxidoreductase. This enzyme catalyses the following chemical reaction : a long-chain acyl-CoA + electron-transfer flavoprotein \rightleftharpoons a long-chain trans-2,3-dehydroacyl-CoA + reduced electron-transfer flavoprotein This enzyme contains FAD as prosthetic group and participates in fatty acid metabolism and PPAR signaling pathway. Mitochondrial mutations in this enzyme may be associated with some forms of dilated cardiomyopathy.
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In enzymology, a methylmalonyl-CoA decarboxylase () is an enzyme that catalyzes the chemical reaction :(S)-methylmalonyl-CoA \rightleftharpoons propanoyl-CoA + CO2 Hence, this enzyme has one substrate, (S)-methylmalonyl- CoA, and two products, propanoyl-CoA and CO2. This enzyme belongs to the family of lyases, specifically the carboxy-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is (S)-methylmalonyl-CoA carboxy-lyase (propanoyl-CoA-forming). Other names in common use include propionyl-CoA carboxylase, propionyl coenzyme A carboxylase, methylmalonyl- coenzyme A decarboxylase, (S)-2-methyl-3-oxopropanoyl-CoA carboxy-lyase [incorrect], and (S)-methylmalonyl-CoA carboxy-lyase.
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In enzymology, a succinate-hydroxymethylglutarate CoA-transferase () is an enzyme that catalyzes the chemical reaction :succinyl-CoA + 3-hydroxy-3-methylglutarate \rightleftharpoons succinate + (S)-3-hydroxy-3-methylglutaryl-CoA Thus, the two substrates of this enzyme are succinyl-CoA and 3-hydroxy-3-methylglutarate, whereas its two products are succinate and (S)-3-hydroxy-3-methylglutaryl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is succinyl-CoA:3-hydroxy-3-methylglutarate CoA- transferase. Other names in common use include hydroxymethylglutarate coenzyme A-transferase, and dicarboxyl-CoA:dicarboxylic acid coenzyme A transferase.
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Sodium fluoroacetate is one of the few naturally occurring fluorine compounds and is present in D. cymosum. The toxic compound isolated as the cause of gifblaar poisoning is fluoroacetate, which was first isolated by Marais in 1944. The of this compound is 0.5 mg/kg which translates to about 200 g of dry plant material to kill a 500 kg cow. The compound itself is not toxic but undergoes lethal synthesis in the body while reacting with coenzyme A, yielding fluoroacetyl-Coenzyme A. This compound reacts with oxaloacetate to form fluorocitrate, which is toxic, being an alternate substrate for aconitase (normal substrate citrate).
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Glutathione disulfide (GSSG) is a disulfide derived from two glutathione molecules. In living cells, glutathione disulfide is reduced into two molecules of glutathione with reducing equivalents from the coenzyme NADPH. This reaction is catalyzed by the enzyme glutathione reductase. Antioxidant enzymes, such as glutathione peroxidases and peroxiredoxins, generate glutathione disulfide during the reduction of peroxides such as hydrogen peroxide (H2O2) and organic hydroperoxides (ROOH): :2 GSH + ROOH → GSSG + ROH + H2O Other enzymes, such as glutaredoxins, generate glutathione disulfide through thiol-disulfide exchange with protein disulfide bonds or other low molecular mass compounds, such as coenzyme A disulfide or dehydroascorbic acid.
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In enzymology, an acyl-CoA oxidase () is an enzyme that catalyzes the chemical reaction :acyl-CoA + O2 \rightleftharpoons trans-2,3-dehydroacyl-CoA + H2O2 Thus, the two substrates of this enzyme are acyl-CoA and O2, whereas its two products are trans-2,3-dehydroacyl-CoA and H2O2. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with oxygen as acceptor. The systematic name of this enzyme class is acyl-CoA:oxygen 2-oxidoreductase. Other names in common use include fatty acyl-CoA oxidase, acyl coenzyme A oxidase, and fatty acyl-coenzyme A oxidase.
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Typically, initial signs and symptoms of this disorder occur during infancy or early childhood and can include poor appetite, vomiting, diarrhea, lethargy, hypoglycemia, hypotonia, liver problems, and hyperinsulinism (high levels of insulin). Insulin controls the amount of sugar that moves from the blood into cells for conversion to energy. Individuals with 3-hydroxyacyl- coenzyme A dehydrogenase deficiency are also at risk for complications such as seizures, life-threatening heart and breathing problems, coma, and sudden unexpected death. Problems related to 3-hydroxyacyl-coenzyme A dehydrogenase deficiency can be triggered by periods of fasting or by illnesses such as viral infections.
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In that study, 106 weeks of adjunctive treatment of chronic heart failure patients with 3 times 100 milligrams of a daily ubiquinone Coenzyme Q10 supplement in addition to conventional heart failure medicine was associated with significant reductions in major adverse cardiovascular events, cardiovascular mortality, all-cause mortality, and hospitalizations as compared to placebo. In the European segment of the Q-Symbio Study, the active Coenzyme Q10 treatment also increased the patients’ left ventricular ejection fraction significantly. During a period of high exertion in 1998, Judy had a major heart attack. This left him with a very weak heart.
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The protein encoded by the ACOT2 gene is part of a family of Acyl-CoA thioesterases, which catalyze the hydrolysis of various Coenzyme A esters of various molecules to the free acid plus CoA. These enzymes have also been referred to in the literature as acyl-CoA hydrolases, acyl-CoA thioester hydrolases, and palmitoyl-CoA hydrolases. The reaction carried out by these enzymes is as follows: CoA ester + H2O → free acid + coenzyme A These enzymes use the same substrates as long-chain acyl-CoA synthetases, but have a unique purpose in that they generate the free acid and CoA, as opposed to long-chain acyl-CoA synthetases, which ligate fatty acids to CoA, to produce the CoA ester. The role of the ACOT- family of enzymes is not well understood; however, it has been suggested that they play a crucial role in regulating the intracellular levels of CoA esters, Coenzyme A, and free fatty acids.
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The protein encoded by the ACOT11 gene is part of a family of Acyl-CoA thioesterases, which catalyze the hydrolysis of various Coenzyme A esters of various molecules to the free acid plus CoA. These enzymes have also been referred to in the literature as acyl-CoA hydrolases, acyl-CoA thioester hydrolases, and palmitoyl-CoA hydrolases. The reaction carried out by these enzymes is as follows: CoA ester + H2O → free acid + coenzyme A These enzymes use the same substrates as long-chain acyl-CoA synthetases, but have a unique purpose in that they generate the free acid and CoA, as opposed to long-chain acyl-CoA synthetases, which ligate fatty acids to CoA, to produce the CoA ester. The role of the ACOT- family of enzymes is not well understood; however, it has been suggested that they play a crucial role in regulating the intracellular levels of CoA esters, Coenzyme A, and free fatty acids.
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The protein encoded by the ACOT4 gene is part of a family of Acyl-CoA thioesterases, which catalyze the hydrolysis of various Coenzyme A esters of various molecules to the free acid plus CoA. These enzymes have also been referred to in the literature as acyl-CoA hydrolases, acyl-CoA thioester hydrolases, and palmitoyl-CoA hydrolases. The reaction carried out by these enzymes is as follows: CoA ester + H2O → free acid + coenzyme A These enzymes use the same substrates as long-chain acyl-CoA synthetases, but have a unique purpose in that they generate the free acid and CoA, as opposed to long-chain acyl-CoA synthetases, which ligate fatty acids to CoA, to produce the CoA ester. The role of the ACOT- family of enzymes is not well understood; however, it has been suggested that they play a crucial role in regulating the intracellular levels of CoA esters, Coenzyme A, and free fatty acids.
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The protein encoded by the ACOT1 gene is part of a family of Acyl- CoA thioesterases, which catalyze the hydrolysis of various Coenzyme A esters of various molecules to the free acid plus CoA. These enzymes have also been referred to in the literature as acyl-CoA hydrolases, acyl-CoA thioester hydrolases, and palmitoyl-CoA hydrolases. The reaction carried out by these enzymes is as follows: CoA ester + H2O → free acid + coenzyme A These enzymes use the same substrates as long-chain acyl-CoA synthetases, but have a unique purpose in that they generate the free acid and CoA, as opposed to long-chain acyl-CoA synthetases, which ligate fatty acids to CoA, to produce the CoA ester. The role of the ACOT- family of enzymes is not well understood; however, it has been suggested that they play a crucial role in regulating the intracellular levels of CoA esters, Coenzyme A, and free fatty acids.
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The protein encoded by the ACOT1 gene is part of a family of Acyl-CoA thioesterases, which catalyze the hydrolysis of various Coenzyme A esters of various molecules to the free acid plus CoA. These enzymes have also been referred to in the literature as acyl-CoA hydrolases, acyl-CoA thioester hydrolases, and palmitoyl-CoA hydrolases. The reaction carried out by these enzymes is as follows: CoA ester + H2O → free acid + coenzyme A These enzymes use the same substrates as long-chain acyl-CoA synthetases, but have a unique purpose in that they generate the free acid and CoA, as opposed to long-chain acyl-CoA synthetases, which ligate fatty acids to CoA, to produce the CoA ester. The role of the ACOT- family of enzymes is not well understood; however, it has been suggested that they play a crucial role in regulating the intracellular levels of CoA esters, Coenzyme A, and free fatty acids.
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The protein encoded by the ACOT13 gene is part of a family of Acyl-CoA thioesterases, which catalyze the hydrolysis of various Coenzyme A esters of various molecules to the free acid plus CoA. These enzymes have also been referred to in the literature as acyl-CoA hydrolases, acyl-CoA thioester hydrolases, and palmitoyl-CoA hydrolases. The reaction carried out by these enzymes is as follows: CoA ester + H2O → free acid + coenzyme A These enzymes use the same substrates as long-chain acyl-CoA synthetases, but have a unique purpose in that they generate the free acid and CoA, as opposed to long-chain acyl-CoA synthetases, which ligate fatty acids to CoA, to produce the CoA ester. The role of the ACOT- family of enzymes is not well understood; however, it has been suggested that they play a crucial role in regulating the intracellular levels of CoA esters, Coenzyme A, and free fatty acids.
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Biotin is a coenzyme for multiple carboxylase enzymes, which are involved in the digestion of carbohydrates, synthesis of fatty acids, and gluconeogenesis. Biotin is also required for the catabolism and utilization of the three branched-chain amino acids: leucine, isoleucine, and valine.
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806 requiring energy rendered from ATP. Malonyl-CoA is utilised in fatty acid biosynthesis by the enzyme malonyl coenzyme A:acyl carrier protein transacylase (MCAT). MCAT serves to transfer malonate from malonyl-CoA to the terminal thiol of holo-acyl carrier protein (ACP).
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Consequently, unlike exogenously administered antioxidants (e.g., vitamin E or Coenzyme Q10), which provide a specific and finite antioxidative potential, omaveloxolone, through Nrf2, broadly activates intracellular and mitochondrial antioxidative pathways, in addition to pathways that may directly increase mitochondrial biogenesis (such as PGC1α) and bioenergetics.
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It can be found in Corynebacterium cyclohexanicum and in Pseudomonas sp. The enzyme 4-hydroxybenzoate decarboxylase uses 4-hydroxybenzoate to produce phenol and CO2. This enzyme participates in benzoate degradation via coenzyme A (CoA) ligation. It can be found in Klebsiella aerogenes (Aerobacter aerogenes).
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PurN GAR transformylase 1CDE uses the coenzyme N10-formyltetrahydrofolate (N10-formyl-THF) as a formyl donor to formylate the α-amino group of GAR. In eukaryotes, PurN GAR transformylase is part of a large multifunctional protein, but is found as a single protein in prokaryotes.
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15, . His strategy of penetrating into the structure of enzyme-substrate interactions by concentrating on the detailed stereochemical fate of isotopic substrate labels, led him to make basic contributions to the mechanism of enzymic reactions requiring coenzyme B12, one of the 'pigments of life'.
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It catalyzes the transfer of electrons from NADH to coenzyme Q10 (CoQ10) and, in eukaryotes, it is located in the inner mitochondrial membrane. This enzyme helps to establish a transmembrane difference of proton electrochemical potential that the ATP synthase then uses to synthesize ATP.
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Specificity for these protein-bound groups is a feature that differentiates the HMGS homologs found in primary metabolism, where HMGS typically acts on substrates linked to Coenzyme A, from those found in non- ribosomal peptide synthase (NRPS) or PKS pathways such as the bryostatin pathway.
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In enzymology, an ADP-dependent short-chain-acyl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :acyl-CoA + H2O \rightleftharpoons CoA + a carboxylate Thus, the two substrates of this enzyme are acyl-CoA and H2O, whereas its two products are CoA and carboxylate. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is ADP-dependent-short-chain-acyl-CoA hydrolase. Other names in common use include short-chain acyl coenzyme A hydrolase, propionyl coenzyme A hydrolase, propionyl-CoA hydrolase, propionyl- CoA thioesterase, short-chain acyl-CoA hydrolase, and short-chain acyl-CoA thioesterase.
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In enzymology, a 4-hydroxybenzoate—CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + 4-hydroxybenzoate + CoA \rightleftharpoons AMP + diphosphate + 4-hydroxybenzoyl-CoA The 3 substrates of this enzyme are ATP, 4-hydroxybenzoate, and CoA, whereas its 3 products are AMP, diphosphate, and 4-hydroxybenzoyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is 4-hydroxybenzoate:CoA ligase (AMP- forming). Other names in common use include 4-hydroxybenzoate-CoA synthetase, 4-hydroxybenzoate-coenzyme A ligase (AMP-forming), 4-hydroxybenzoyl coenzyme A synthetase, and 4-hydroxybenzoyl-CoA ligase.
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Crystal structure of Tetrahymena Gcn5 with bound coenzyme A and histone H3 peptide (PDB 1QSN). The central core (green), flanking N- and C-terminal segments (blue), coenzyme A (orange), and histone peptide (red) are shown. In general, HATs are characterized by a structurally conserved core region made up of a three- stranded β-sheet followed by a long α-helix parallel to and spanning one side of it. The core region, which corresponds to motifs A, B, and D of the GNAT proteins, is flanked on opposite sides by N- and C-terminal α/β segments that are structurally unique for a given HAT family.
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Two monomers(left and right) are shown and the coenzyme PLP is placed in the crevice between the two domains. Two Dimers: Two monomers of hSDS (human SDH) come together to make a dimer. The interface between the two monomers is formed through hydrogen bonds and hydrophobic interactions. The monomer–monomer contacts involve six pairs of hydrogen bonds formed between 10 residues (Arg98-Asn260, Leu310-Asn260, and Leu265-Lys263). Additional interactions include a number of hydrophobic contacts between the residues Met17, Lys21, Asn101, Glu102, Ser306, Ile308, Ser309, and Ile264 in each monomer. (Figure 2). File:PLPmoleculeSDH.jpg Figure 2 shows the PLP coenzyme situated in the active site of SDH.
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The reductive acetyl–CoA pathway The Wood–Ljungdahl pathway is a set of biochemical reactions used by some bacteria and archaea called acetogens and methanogens, respectively. It is also known as the reductive acetyl-coenzyme A (Acetyl-CoA) pathway. This pathway enables these organisms to use hydrogen as an electron donor, and carbon dioxide as an electron acceptor and as a building block for biosynthesis. In this pathway carbon dioxide is reduced to carbon monoxide and formic acid or directly into a formyl group, the formyl group is reduced to a methyl group and then combined with the carbon monoxide and Coenzyme A to produce acetyl-CoA.
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In enzymology, an isovaleryl-CoA dehydrogenase () is an enzyme that catalyzes the chemical reaction :3-methylbutanoyl-CoA + acceptor \rightleftharpoons 3-methylbut-2-enoyl-CoA + reduced acceptor Thus, the two substrates of this enzyme are 3-methylbutanoyl-CoA and acceptor, whereas its two products are 3-methylbut-2-enoyl-CoA and reduced acceptor. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with other acceptors. The systematic name of this enzyme class is 3-methylbutanoyl-CoA:acceptor oxidoreductase. Other names in common use include isovaleryl-coenzyme A dehydrogenase, isovaleroyl-coenzyme A dehydrogenase, and 3-methylbutanoyl-CoA:(acceptor) oxidoreductase.
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Despite the presence of the de novo pathway, the salvage reactions are essential in humans; a lack of niacin in the diet causes the vitamin deficiency disease pellagra. This high requirement for NAD results from the constant consumption of the coenzyme in reactions such as posttranslational modifications, since the cycling of NAD between oxidized and reduced forms in redox reactions does not change the overall levels of the coenzyme. The major source of NAD in mammals is the salvage pathway which recycles the nicotinamide produced by enzymes utilizing NAD. The first step, and the rate-limiting enzyme in the salvage pathway is nicotinamide phosphoribosyltransferase (NAMPT), which produces nicotinamide mononucleotide (NMN).
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Coenzyme A is produced commercially via extraction from yeast, however this is an inefficient process (yields approximately 25 mg/kg) resulting in an expensive product. Various ways of producing CoA synthetically, or semi-synthetically have been investigated although none are currently operating at an industrial scale.
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This gene encodes a member of the 3-oxoacid CoA-transferase gene family. The encoded protein is a homodimeric mitochondrial matrix enzyme that plays a central role in extrahepatic ketone body catabolism by catalyzing the reversible transfer of coenzyme A (CoA) from succinyl-CoA to acetoacetate.
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The pathway used is called the ubiquinone biosynthesis pathway, it catalyzes the first step in the biosynthesis of ubiquinone in E. coli. Ubiquinone is a lipid-soluble electron- transporting coenzyme. They are essential electron carriers in prokaryotes and are essential in aerobic organisms to achieve ATP.
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The alcohol dehydrogenases comprise a group of several isozymes that catalyse the oxidation of primary and secondary alcohols to aldehydes and ketones, respectively, and also can catalyse the reverse reaction. In mammals this is a redox (reduction/oxidation) reaction involving the coenzyme nicotinamide adenine dinucleotide (NAD+).
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However, depending on pH and temperature, methanogenesis has been shown to use carbon from other small organic compounds, such as formic acid (formate), methanol, methylamines, tetramethylammonium, dimethyl sulfide, and methanethiol. The catabolism of the methyl compounds is mediated by methyl transferases to give methyl coenzyme M.
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PLP, the metabolically active form of vitamin B6, is involved in many aspects of macronutrient metabolism, neurotransmitter synthesis, histamine synthesis, hemoglobin synthesis and function, and gene expression. PLP generally serves as a coenzyme (cofactor) for many reactions including decarboxylation, transamination, racemization, elimination, replacement, and beta-group interconversion.
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The predominant ubiquinone is coenzyme Q-7 and the diazonium blue B test is negative. Some species are used and cultured for microbiological en genetic research e.g. Ogataea polymorpha, Ogataea minuta or Ogataea methanolica. Ogataea minuta (Wickerham) Y. Yamada, K. Maeda & Mikata is the type species for this genus.
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Cobamide is a naturally occurring chemical compound containing cobalt in the corrinoid family of macrocyclic complexes. Cobamide works as a coenzyme with some enzymes in bacteria. The cobalt atom may have a transferable methyl group attached. It is used for example in 5-methyltetrahydrosarcinapterin:corrinoid/iron-sulfur protein Co- methyltransferase.
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Ribonucleoside-triphosphate reductase (, ribonucleotide reductase, 2'-deoxyribonucleoside-triphosphate:oxidized-thioredoxin 2'-oxidoreductase) is an enzyme with systematic name 2'-deoxyribonucleoside- triphosphate:thioredoxin-disulfide 2'-oxidoreductase. This enzyme catalyses the following chemical reaction : 2'-deoxyribonucleoside triphosphate + thioredoxin disulfide + H2O \rightleftharpoons ribonucleoside triphosphate + thioredoxin Ribonucleoside-triphosphate reductase requires a cobamide coenzyme and ATP.
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Drug therapy can slow down progression and in some cases even improve the heart condition. Standard therapy may include salt restriction, ACE inhibitors, diuretics, and beta blockers. Anticoagulants may also be used for antithrombotic therapy. There is some evidence for the benefits of coenzyme Q10 in treating heart failure.
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Sterols are a subgroup of steroids with a hydroxyl group at the 3-position of the A-ring. They are amphipathic lipids synthesized from acetyl-coenzyme A via the HMG-CoA reductase pathway. The overall molecule is quite flat. The hydroxyl group on the A ring is polar.
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2-Phospho-L-lactate guanylyltransferase (, CofC, MJ0887) is an enzyme with systematic name GTP:2-phospho-L-lactate guanylyltransferase. This enzyme catalyses the following chemical reaction : (2S)-2-phospholactate + GTP \rightleftharpoons (2S)-lactyl-2-diphospho-5'-guanosine + diphosphate This enzyme is involved in the biosynthesis of coenzyme F420.
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ADP binds behind the NAD-BD, just beneath the pivot helix - the second coenzyme binding site. The adenosine moiety binds down into a hydrophobic pocket with the ribose phosphate groups pointing up toward the pivot helix. ADP can also bind to the second, inhibitory, NADH-site yet causes activation.
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It is the one- carbon donor for thymidylate synthase, for methylation of 2-deoxy- uridine-5-monophosphate (dUMP) to 2-deoxy-thymidine-5-monophosphate (dTMP). The coenzyme is necessary for the biosynthesis of thymidine and is the C1-donor in the reactions catalyzed by TS and thymidylate synthase (FAD).
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In enzymology, formate C-acetyltransferase (pyruvate formate lyase) () is an enzyme. Pyruvate formate lyase is found in Escherichia coli and other organisms. It helps regulate anaerobic glucose metabolism. Using radical non- redox chemistry, it catalyzes the reversible conversion of pyruvate and coenzyme-A into formate and acetyl-CoA.
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Acyl-coenzyme A:cholesterol acyltransferase () is an intracellular protein located in the endoplasmic reticulum that forms cholesterol esters from cholesterol. Accumulation of cholesterol esters as cytoplasmic lipid droplets within macrophages and smooth muscle cells is a characteristic feature of the early stages of atherosclerotic plaques (Cadigan et al., 1988).
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AKR1A1 consists of 325 amino acids and weighs 36573Da. The tertiary structure consists of a beta/alpha- barrel, with the coenzyme-binding site located at the carboxy-terminus end of the strands of the barrel. Alternative splicing of this gene results in two transcript variants encoding the same protein.
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Thioesters are prominent active esters, as illustrated by the esters of coenzyme A. In synthetic chemistry, active esters include derivatives of nitrophenols and pentafluorophenol. Active esters are often used in peptide synthesis, e.g., N-hydroxysuccinimide, hydroxybenzotriazole. Active esters of acrylic acid are precursors to polymers with reactive side chains.
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In enzymology, a succinate-CoA ligase (ADP-forming) () is an enzyme that catalyzes the chemical reaction :ATP + succinate + CoA \rightleftharpoons ADP + phosphate + succinyl-CoA The 3 substrates of this enzyme are ATP, succinate, and CoA, whereas its 3 products are ADP, phosphate, and succinyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon- sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is succinate:CoA ligase (ADP-forming). Other names in common use include succinyl-CoA synthetase (ADP-forming), succinic thiokinase, succinate thiokinase, succinyl-CoA synthetase, succinyl coenzyme A synthetase (adenosine diphosphate-forming), succinyl coenzyme A synthetase, A-STK (adenin nucleotide-linked succinate thiokinase), STK, and A-SCS.
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Under normal conditions, acetyl-CoA is further oxidized by the citric acid cycle (TCA/Krebs cycle) and then by the mitochondrial electron transport chain to release energy. However, if the amounts of acetyl-CoA generated in fatty-acid β-oxidation challenge the processing capacity of the TCA cycle; i.e. if activity in TCA cycle is low due to low amounts of intermediates such as oxaloacetate, acetyl-CoA is then used instead in biosynthesis of ketone bodies via acetoacetyl-CoA and β-hydroxy-β- methylglutaryl-CoA (HMG-CoA). Furthermore, since there is only a limited amount of coenzyme A in the liver, the production of ketogenesis allows some of the coenzyme to be freed to continue fatty-acid β-oxidation.
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In enzymology, a 2-furoyl-CoA dehydrogenase () is an enzyme that catalyzes the chemical reaction :2-furoyl-CoA + H2O + acceptor \rightleftharpoons S-(5-hydroxy-2-furoyl)-CoA + reduced acceptor The 3 substrates of this enzyme are 2-furoyl-CoA, H2O, and acceptor, whereas its two products are S-(5-hydroxy-2-furoyl)-CoA and reduced acceptor. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with other acceptors. The systematic name of this enzyme class is 2-furoyl-CoA:acceptor 5-oxidoreductase (hydroxylating). Other names in common use include furoyl-CoA hydroxylase, 2-furoyl coenzyme A hydroxylase, 2-furoyl coenzyme A dehydrogenase, and 2-furoyl-CoA:(acceptor) 5-oxidoreductase (hydroxylating).
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A nickel-tetrapyrrole coenzyme, cofactor F430, is present in methyl coenzyme M reductase, which can catalyze the formation of methane, or the reverse reaction, in methanogenic archaea (in +1 oxidation state). One of the carbon monoxide dehydrogenase enzymes consists of an Fe-Ni-S cluster. Other nickel-bearing enzymes include a rare bacterial class of superoxide dismutase and glyoxalase I enzymes in bacteria and several parasitic eukaryotic trypanosomal parasites (in higher organisms, including yeast and mammals, this enzyme contains divalent Zn2+). Dietary nickel may affect human health through infections by nickel-dependent bacteria, but it is also possible that nickel is an essential nutrient for bacteria residing in the large intestine, in effect functioning as a prebiotic.
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Energy obtained through the transfer of electrons down the electron transport chain is used to pump protons from the mitochondrial matrix into the intermembrane space, creating an electrochemical proton gradient (ΔpH) across the inner mitochondrial membrane. This proton gradient is largely but not exclusively responsible for the mitochondrial membrane potential (ΔΨM). It allows ATP synthase to use the flow of H+ through the enzyme back into the matrix to generate ATP from adenosine diphosphate (ADP) and inorganic phosphate. Complex I (NADH coenzyme Q reductase; labeled I) accepts electrons from the Krebs cycle electron carrier nicotinamide adenine dinucleotide (NADH), and passes them to coenzyme Q (ubiquinone; labeled Q), which also receives electrons from complex II (succinate dehydrogenase; labeled II).
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Succinate-semialdehyde dehydrogenase (acylating) (, succinyl-coA reductase, coenzyme-A-dependent succinate-semialdehyde dehydrogenase) is an enzyme with systematic name succinate semialdehyde:NADP+ oxidoreductase (CoA-acylating). This enzyme catalyses the following chemical reaction : succinate semialdehyde + CoA + NADP+ \rightleftharpoons succinyl-CoA + NADPH + H+ Catalyses the NADPH-dependent reduction of succinyl-CoA to succinate semialdehyde.
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Propionibacterium is a gram-positive, anaerobic, rod-shaped genus of bacteria named for their unique metabolism: They are able to synthesize propionic acid by using unusual transcarboxylase enzymes.Cheung, Y.F., Fung, C., and Walsh, C. "Stereochemistry of propionyl-coenzyme A and pyruvate carboxylations catalyzed by transcarboxylase." 1975. Biochemistry 14(13), pg 2981.
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Collectively E1-E3 transform pyruvate, NAD+, coenzyme A into acetyl-CoA, CO2, and NADH. The conversion is crucial because acetyl-CoA may then be used in the citric acid cycle to carry out cellular respiration.. To distinguish between this enzyme and the PDC, it is systematically called pyruvate dehydrogenase (acetyl-transferring).
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Vitamin B6 refers to a group of chemically similar compounds which can be interconverted in biological systems. Vitamin B6 is part of the vitamin B group of essential nutrients. Its active form, pyridoxal 5′-phosphate, serves as a coenzyme in some 100 enzyme reactions in amino acid, glucose, and lipid metabolism.
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While circulating in blood, chylomicrons exchange components with high-density lipoproteins (HDL). The HDL donates apolipoprotein C-II (APOC2) and apolipoprotein E (APOE) to the nascent chylomicron and, thus, converts it to a mature chylomicron (often referred to simply as "chylomicron"). APOC2 is the coenzyme for lipoprotein lipase (LPL) activity.
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NADH-Q oxidoreductase. The abbreviations are discussed in the text. In all diagrams of respiratory complexes in this article, the matrix is at the bottom, with the intermembrane space above. NADH-coenzyme Q oxidoreductase, also known as NADH dehydrogenase or complex I, is the first protein in the electron transport chain.
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It is capable of undergoing oxidation and reduction as its iron atom converts between the ferrous and ferric forms, but does not bind oxygen. It transfers electrons between Complexes III (Coenzyme Q – Cyt C reductase) and IV (Cyt C oxidase). In humans, cytochrome c is encoded by the CYCS gene.
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First-line drugs for the prevention of migraine attacks include the beta blockers propranolol, metoprolol and bisoprolol, the antiepileptics valproic acid and topiramate, as well as flunarizine. Less well evidenced is the use of amitriptyline, venlafaxine, Petasites albus extract, riboflavin (vitamin B2), magnesium, coenzyme Q10, gabapentin, acetylsalicylic acid, and naproxen.
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Manganese is an essential human dietary element. It is present as a coenzyme in several biological processes, which include macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. The human body contains about 12 mg of manganese, mostly in the bones.
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Trifunctional enzyme subunit alpha, mitochondrial also known as hydroxyacyl- CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase (trifunctional protein), alpha subunit is a protein that in humans is encoded by the HADHA gene. Mutations in HADHA have been associated with trifunctional protein deficiency or long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency.
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There is currently no defined treatment to ameliorate the muscle weakness of CPEO. Treatments used to treat other pathologies causing ophthalmoplegia has not been shown to be effective. Experimental treatment with tetracycline has been used to improve ocular motility in one patient. Coenzyme Q10 has also been used to treat this condition.
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It was not until 1945 that Coenzyme A (CoA) was discovered simultaneously and independently by three laboratories, Nachmansohn's being one of these. Subsequently, acetyl-CoA, at the time called “active acetate,” was discovered in 1951. The 3D structure of rat-derived ChAT was not solved until nearly 60 years later, in 2004.
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Solanesol is a non-cyclic terpene alcohol that consists of nine isoprene units and mainly accumulates in solanaceous plants such as tobacco, potato, and tomato. It is also accumulates in eggplant and pepper plants. It is notable as the biosynthetic precursor to coenzyme Q10. The leaf tobacco contains the tobacco-specific compound solanesol.
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These protons move back through the membrane as they drive the ATP synthase, as before. The electrons then flow through photosystem I and can then either be used to reduce the coenzyme NADP+.fThese cooenzyme can be used in the Calvin cycle, which is discussed below, or recycled for further ATP generation.
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Isobutyryl-coenzyme A dehydrogenase deficiency, is a rare metabolic disorder in which the body is unable to process certain amino acids properly. People with this disorder have inadequate levels of an enzyme that helps break down the amino acid valine, resulting in a buildup of valine in the urine, a symptom called valinuria.
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By contrast, the course of recovery in the placebo group was longer (15–30 days) and more complicated. There was a positive relationship between blood and heart muscle Coenzyme Q10 levels, heart muscle ATP levels, and indicators of heart function, on the one hand, and post-operative recovery time, on the other hand.
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Glycerol-3-phosphate gets converted back to dihydroxyacetone phosphate by an inner membrane-bound mitochondrial glycerol-3-phosphate dehydrogenase 2 (GPDH-M), this time reducing one molecule of enzyme-bound flavin adenine dinucleotide (FAD) to FADH2. FADH2 then reduces coenzyme Q (ubiquinone to ubiquinol) which enters into oxidative phosphorylation. This reaction is irreversible.
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Adrenodoxin is a small iron-sulfur protein that can accept and carry a single electron. Adrenodoxin functions as an electron transfer protein in the mitochondrial cytochrome P450 systems. The first enzyme in this system is adrenodoxin reductase that carries an FAD. FAD can be reduced by two electrons donated from coenzyme NADPH.
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Purine metabolism involves the formation of adenine and guanine. Both adenine and guanine are derived from the nucleotide inosine monophosphate (IMP), which in turn is synthesized from a pre-existing ribose phosphate through a complex pathway using atoms from the amino acids glycine, glutamine, and aspartic acid, as well as the coenzyme tetrahydrofolate.
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The MT-ND5 product is a subunit of the respiratory chain Complex I that is supposed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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In enzymology, a biotin-[methylmalonyl-CoA-carboxytransferase] ligase () is an enzyme that catalyzes the chemical reaction :ATP + biotin + apo-[methylmalonyl-CoA:pyruvate carboxytransferase] \rightleftharpoons AMP + diphosphate + [methylmalonyl-CoA:pyruvate carboxytransferase] The 3 substrates of this enzyme are ATP, biotin, and apo-[methylmalonyl-CoA:pyruvate carboxytransferase], whereas its 3 products are AMP, diphosphate, and methylmalonyl-CoA:pyruvate carboxytransferase. This enzyme belongs to the family of ligases, specifically those forming generic carbon-nitrogen bonds. The systematic name of this enzyme class is biotin:apo[methylmalonyl- CoA:pyruvate carboxytransferase] ligase (AMP-forming). Other names in common use include biotin-[methylmalonyl-CoA-carboxyltransferase] synthetase, biotin- methylmalonyl coenzyme A carboxyltransferase synthetase, biotin- transcarboxylase synthetase, methylmalonyl coenzyme A holotranscarboxylase synthetase, biotin-[methylmalonyl-CoA-carboxyltransferase] ligase, biotin:apo[methylmalonyl-CoA:pyruvate carboxyltransferase] ligase, and (AMP- forming).
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His group has pioneered investigations that have led to both deep understanding and recognition of the general importance of quantum tunnelling and protein dynamics in enzyme H-transfer and conformational ensemble sampling in electron transfer reactions. This has involved the development of new biophysical approaches for reaction kinetics analysis including kinetic isotope effect studies, their integration into structural and computational programmes, and extension of theory. He has also made important contributions to enzyme kinetics, coenzyme chemistry, protein engineering, directed evolution, synthetic biology, biological engineering, biocatalysis and metabolic engineering, including the first rational redesign of the coenzyme specificity of an enzyme, the establishment of automated microorganism bioengineering platforms for the production of chemicals (e.g. fuels, materials, active pharmaceutical ingredients) and the discovery of new riboflavin cofactors.
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The MT-ND6 product is a subunit of the respiratory chain Complex I that is believed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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MT-ND4 is a subunit of the respiratory chain Complex I that is believed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The MT-ND4L product is a subunit of the respiratory chain Complex I that is believed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The MT-ND2 product is a subunit of the respiratory chain Complex I that is believed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The MT-ND3 product is a subunit of the respiratory chain Complex I that is believed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The first of Bachhawat's major research findings came when he was working with Minor J. Coon at the University of Michigan. Both the scientists together discovered HMG-CoA lyase, an intermediate in the mevalonate and ketogenesis pathway, thus broadening the understanding of the formation of ketone bodies in mammals, which was later elucidated further in his article Enzymic cleavage of p-Hydroxy-f3-Methyl-Glutaryl coenzyme A 10 acetoacctate and acetyl coenzyme A., published in 1995. On his return to India, he focused his studies on amino acids and inorganic sulphate metabolism, as well as glycosaminoglycan. His researches revealed, for the first time, that Metachromatic leukodystrophy, an autosomal recessive disease, was caused by the absence of Arylsulfatase A, an enzyme responsible for the breaking down on sulfatides.
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"Arsenic-loving bacteria rewrite photosynthesis rules", Chemistry World, 15 August 2008 In humans, arsenite inhibits pyruvate dehydrogenase (PDH complex) in the pyruvate–acetyl CoA reaction, by binding to the –SH group of lipoamide, a participant coenzyme. It also inhibits the oxoglutarate dehydrogenase complex by the same mechanism. The inhibition of these enzymes disrupts energy production.
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Alcohol-forming fatty acyl-CoA reductase (, FAR (gene)) is an enzyme with systematic name long-chain acyl-CoA:NADPH reductase. This enzyme catalyses the following chemical reaction : a long-chain acyl-CoA + 2 NADPH + 2 H+ \rightleftharpoons a long-chain alcohol + 2 NADP+ \+ coenzyme A The enzyme has been characterized from the plant Simmondsia chinensis.
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Pantoic acid is an alpha hydroxy acid which is a component of some biologically active compounds. The amide of pantoic acid with β-alanine is pantothenic acid (vitamin B5)Pantoic acid, Merriam Webster Medical Dictionary and the amide with GABA is the pharmaceutical drug hopantenic acid. It is also a central component of coenzyme A.
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Other major lipid classes in the fatty acid category are the fatty esters and fatty amides. Fatty esters include important biochemical intermediates such as wax esters, fatty acid thioester coenzyme A derivatives, fatty acid thioester ACP derivatives and fatty acid carnitines. The fatty amides include N-acyl ethanolamines, such as the cannabinoid neurotransmitter anandamide.
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Very long-chain acyl-coenzyme A dehydrogenase deficiency is a fatty-acid metabolism disorder which prevents the body from converting certain fats to energy, particularly during periods without food.update 2014 Those affected by this disorder have inadequate levels of an enzyme that breaks down a group of fats called very long-chain fatty acids.
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It is generated in nature from phenylalanine, which is converted by PAL to trans-cinnamate. Trans-cinnamate is hydroxylated by trans- cinnamate 4-monooxygenase to give 4-hydroxycinnamate (i.e, coumarate). Coumarate is condensed with coenzyme-A in the presence of 4-coumarate-CoA ligase: :ATP + 4-coumarate + CoA \rightleftharpoons AMP + diphosphate + 4-coumaroyl-CoA.
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This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acetyl-CoA:taxa-4(20),11-dien-5alpha- ol O-acetyltransferase. Other names in common use include acetyl coenzyme A:taxa-4(20),11(12)-dien-5alpha-ol O-acetyl, and transferase.
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In 1936, Kögl and Tönnis isolated a growth factor from egg yolk they called "Bios aus Eigelb." After experiments performed with yeast and Rhizobium R, West and Wilson isolated a compound they called co-enzyme R. In 1940, Gyorgy proved that vitamin H, Bios aus Eigelb and coenzyme R were the same substance: biotin.
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5: cysteamine. Pantothenic acid is a water-soluble vitamin, one of the B vitamins. It is synthesized from the amino acid β-alanine and pantoic acid (see biosynthesis and structure of coenzyme A figures). Unlike vitamin E, which occurs in eight chemically related forms known as vitamers, pantothenic acid is only one chemical compound.
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Its phosphate derivatives are involved in many cellular processes. The best-characterized form is thiamine pyrophosphate (TPP), a coenzyme in the catabolism of sugars and amino acids. In yeast, TPP is also required in the first step of alcoholic fermentation. All organisms use thiamine, but it is made only in bacteria, fungi, and plants.
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PLOS ONE, 10(12), e0141641. Oxidative stress accompanied by a low-grade inflammatory response appears to aggravate cardiovascular morbidity.Alehagen, U., Lindahl, T. L., Aaseth, J., Svensson, E., & Johansson, P. (2015). Levels of sP-selectin and hs-CRP Decrease with Dietary Intervention with selenium and coenzyme Q10 Combined: a secondary analysis of a randomized clinical trial.
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This gene encodes the alpha subunit of the heterodimeric enzyme succinate coenzyme A ligase. This enzyme is targeted to the mitochondria and catalyzes the conversion of succinyl CoA and ADP or GDP to succinate and ATP or GTP. Mutations in this gene are the cause of the metabolic disorder fatal infantile lactic acidosis and mitochondrial DNA depletion.
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Buparvaquone resistance appears to be associated with parasite mutations in the Qo quinone-binding site of mitochondrial cytochrome b. Its mode of action is thus likely to be similar to that of the antimalarial drug atovaquone, a similar 2-hydroxy-1,4-naphthoquinone that binds to the Qo site of cytochrome b thus inhibiting Coenzyme Q – cytochrome c reductase.
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This process facilitates the production of fatty acids in cells, which are essential in cell membrane structure. Coenzyme A is also the source of the phosphopantetheine group that is added as a prosthetic group to proteins such as acyl carrier protein and formyltetrahydrofolate dehydrogenase.Some of the sources that CoA comes from and uses in the cell.
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Methylmalonyl-CoA is the thioester consisting of coenzyme A linked to methylmalonic acid. It is an important intermediate in the biosynthesis of many organic compounds as well as in the process of carbon assimilation.Tabita, F. R., "The hydroxypropionate pathway of CO2 fixation: Fait accompli", Proceedings of the National Academy of Sciences 2009, vol. 106, 21015-21016.
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Fluoroacetate is structually similar to acetate, which has a pivotal role in cellular metabolism. This similarity is the basis of the toxicity of fluoroacetate. Two related mechanisms for its toxicity have been discussed, both begin with the conversion of fluoroacetate to 2-fluorocitrate. 2-Fluorocitrate arises by condensation with oxaloacetate with fluoroacetyl coenzyme A, catalyzed by citrate synthase.
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Coenzyme Q-10 and pine bark extract have been suggested as beneficial, but neither has been proven in clinical trials. Testosterone is known to reduce Lp(a) levels. Testosterone replacement therapy also appears to be associated with lower Lp(a) levels. One large study suggested that there was a decreased association between Lp(a) levels and risk.
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Thiamine deficiency and errors of thiamine metabolism are believed to be the primary cause of Wernicke encephalopathy. Thiamine, also called B1, helps to break down glucose. Specifically, it acts as an essential coenzyme to the TCA cycle and the pentose phosphate shunt. Thiamine is first metabolised to its more active form, thiamine diphosphate (TDP), before it is used.
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Pyruvate dehydrogenase is an enzyme that catalyzes the reaction of pyruvate and a lipoamide to give the acetylated dihydrolipoamide and carbon dioxide. The conversion requires the coenzyme thiamine pyrophosphate. 350px Pyruvate dehydrogenase is usually encountered as a component, referred to as E1, of the pyruvate dehydrogenase complex (PDC). PDC consists of other enzymes, referred to as E2 and E3.
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This enzyme has 1 substrate, L-serine, and two products, pyruvate and NH3, and uses 1 cofactor, pyridoxal phosphate (PLP). The enzyme's main role is in gluconeogenesis in the liver's cytoplasm. By orienting the substrates and utilizing the PLP coenzyme, SDH lowers the activation energy to convert L-Serine into pyruvate, which can then be converted into glucose.
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Two specific enzymes participate on the carbon monoxide side of the pathway: CO Dehydrogenase and acetyl-CoA synthase. The former catalyzes the reduction of the CO2 and the latter combines the resulting CO with a methyl group to give acetyl-CoA.Paul A. Lindahl "Nickel- Carbon Bonds in Acetyl-Coenzyme A Synthases/Carbon Monoxide Dehydrogenases" Met. Ions Life Sci.
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Vitamins can serve as precursors to many organic cofactors (e.g., vitamins B1, B2, B6, B12, niacin, folic acid) or as coenzymes themselves (e.g., vitamin C). However, vitamins do have other functions in the body. Many organic cofactors also contain a nucleotide, such as the electron carriers NAD and FAD, and coenzyme A, which carries acyl groups.
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There is tentative evidence that coenzyme Q10 reduces migraine frequency. There is tentative evidence for melatonin as an add-on therapy for prevention and treatment of migraine. The data on melatonin are mixed and certain studies have had negative results. The reasons for the mixed findings are unclear but may stem from differences in study design and dosage.
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The vitamin activity is as a coenzyme, meaning that its presence is required for some enzyme-catalyzed reactions. For cyanocobalamin, the R-residue is cyanide. For hydroxocobalamin it is a hydroxyl group. Both of these can be converted to either of the two cobalamin coenzymes that are active in human metabolism: adenosylcobalamin (AdoB12) and methylcobalamin (MeB12).
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This enzyme belongs to the family of transferases, specifically those N-acyltransferases transferring groups other than aminoacyl groups (cd04301). The systematic name of this enzyme class is tetradecanoyl- CoA:glycylpeptide N-tetradecanoyltransferase. Other names in common use include peptide N-myristoyltransferase (NMT), myristoyl-CoA-protein N-myristoyltransferase, myristoyl-coenzyme A:protein N-myristoyl transferase, myristoylating enzymes, and protein N-myristoyltransferase.
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Rosuvastatin is a competitive inhibitor of the enzyme HMG-CoA reductase, having a mechanism of action similar to that of other statins. Putative beneficial effects of rosuvastatin therapy on chronic heart failure may be negated by increases in collagen turnover markers as well as a reduction in plasma coenzyme Q10 levels in patients with chronic heart failure.
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Within little more than a decade, ryegrass and other weeds began to develop resistance. In response Australian farmers changed methods. By 1983, patches of ryegrass had become immune to Hoegrass, a family of herbicides that inhibit an enzyme called acetyl coenzyme A carboxylase. Ryegrass populations were large, and had substantial genetic diversity, because farmers had planted many varieties.
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Accordingly, neuroprotective therapy seeks to delay the introduction of levodopa. Several molecules have been proposed as potential treatments. However, none of them has been conclusively demonstrated to reduce degeneration. Agents currently under investigation include antiapoptotics (omigapil, CEP-1347), antiglutamatergics, monoamine oxidase inhibitors (selegiline, rasagiline), promitochondrials (coenzyme Q10, creatine), calcium channel blockers (isradipine) and growth factors (GDNF).
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At physiological pHs, acetic acid is usually fully ionised to acetate. The acetyl group, formally derived from acetic acid, is fundamental to all forms of life. When bound to coenzyme A, it is central to the metabolism of carbohydrates and fats. Unlike longer-chain carboxylic acids (the fatty acids), acetic acid does not occur in natural triglycerides.
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It is converted into succinate through the hydrolytic release of coenzyme A by succinyl-CoA synthetase (succinate thiokinase). Another fate of succinyl-CoA is porphyrin synthesis, where succinyl-CoA and glycine are combined by ALA synthase to form δ-aminolevulinic acid (dALA). This process is the committed step in the biosynthesis of porfobilinogen and thus hemoglobin.
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Her work established a basis for the later discovery of Coenzyme A.Marilyn Ogilvie and Joy Harvey, eds., The Biographical Dictionary of Women in Science (Routledge 2003): 874-875. She would remain at the institute (later merged with the Institute for Cancer Research) as a research faculty member until 1952. She was a senior member from 1954 to 1960.
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Quinones are mobile, lipid-soluble carriers that shuttle electrons (and protons) between large, relatively immobile macromolecular complexes embedded in the membrane. Bacteria use ubiquinone (Coenzyme Q, the same quinone that mitochondria use) and related quinones such as menaquinone (Vitamin K2). Archaea in the genus Sulfolobus use caldariellaquinone. The use of different quinones is due to slightly altered redox potentials.
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Thereby, through the incorporation of a further O2 molecule, maleylacetoacetate is created. Fumarylacetoacetate is created by maleylacetoacetate cis-trans-isomerase through rotation of the carboxyl group created from the hydroxyl group via oxidation. This cis-trans-isomerase contains glutathione as a coenzyme. Fumarylacetoacetate is finally split by the enzyme fumarylacetoacetate hydrolase through the addition of a water molecule.
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Panthenol readily penetrates into the skin and mucous membranes (including the intestinal mucosa), where it is quickly oxidized to pantothenic acid. Pantothenic acid is extremely hygroscopic, that is, it binds water effectively. It is also used in the biosynthesis of coenzyme A, which plays a role in a wide range of enzymatic reactions and thus in cell growth.
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Cysteamine is a chemical compound that can be biosynthesized in mammals, including humans, by the degradation of coenzyme A. The intermediate pantetheine is broken down into cysteamine and pantothenic acid. It is the biosynthetic precursor to the neurotransmitter hypotaurine. It is a stable aminothiol, i.e., an organic compound containing both an amine and a thiol functional groups.
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Shimwellia is a genus of Gram-negative bacteria of the family Enterobacteriaceae. The two species of Shimwellia are Shimwellia blattae (formerly Escherichia blattae) and Shimwellia pseudoproteus (formerly Obesumbacterium pseudoproteus). Species in Shimwellia are genetically similar to Escherichia but differ in notable ways. S. blattae can synthesize coenzyme B12 and S. pseudoproteus is associated with beer spoilage.
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In a series of papers, dr. Aaseth has disclosed a role of selenium deficiency in the development of cardiovascular morbidity and mortality.Alehagen, U., Aaseth, J., & Johansson, P. (2015). Reduced cardiovascular mortality 10 years after supplementation with selenium and coenzyme Q10 for four years: follow-up results of a prospective randomized double-blind placebo-controlled trial in elderly citizens.
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Peroxisomal acyl-coenzyme A oxidase 3 is an enzyme that in humans is encoded by the ACOX3 gene. Acyl-Coenzyme A oxidase 3 also known as pristanoyl-CoA oxidase (ACOX3) is involved in the desaturation of 2-methyl branched fatty acids in peroxisomes. Unlike the rat homolog, the human gene is expressed in very low amounts in the liver such that its mRNA was undetectable by routine Northern-blot analysis, by immunoblotting for its product, or by enzyme activity measurements. However the human cDNA encoding a 700 amino acid protein with a peroxisomal targeting C-terminal tripeptide S-K-L was isolated and is thought to be expressed under special conditions such as specific developmental stages or in a tissue specific manner in tissues that have not yet been examined.
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MT-ND1-encoded NADH-ubiquinone oxidoreductase chain 1 is a subunit of the respiratory chain Complex I that is supposed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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In enzymology, a biotin-[methylcrotonoyl-CoA-carboxylase] ligase () is an enzyme that catalyzes the chemical reaction :ATP + biotin + apo-[3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP-forming)] \rightleftharpoons AMP + diphosphate + [3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP-forming)] The 3 substrates of this enzyme are ATP, biotin, and apo-[3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP-forming)], whereas its 3 products are AMP, diphosphate, and 3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP-forming). This enzyme belongs to the family of ligases, specifically those forming generic carbon-nitrogen bonds. The systematic name of this enzyme class is biotin:apo-[3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP- forming)] ligase (AMP-forming). Other names in common use include biotin-[methylcrotonoyl-CoA-carboxylase] synthetase, biotin-beta- methylcrotonyl coenzyme A carboxylase synthetase, beta-methylcrotonyl coenzyme A holocarboxylase synthetase, and holocarboxylase-synthetase.
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In enzymology, a dihydroxy-acid dehydratase () is an enzyme that catalyzes the chemical reaction :2,3-dihydroxy-3-methylbutanoate \rightleftharpoons 3-methyl-2-oxobutanoate + H2O Hence, this enzyme has one substrate, 2,3-dihydroxy-3-methylbutanoate, and two products, 3-methyl-2-oxobutanoate (α-ketoisovaleric acid) and H2O. This enzyme participates in valine, leucine and isoleucine biosynthesis and pantothenate and coenzyme A (CoA) biosynthesis.
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Pseudomonas alkanolytica is a Gram-negative soil bacterium that produces Coenzyme A. Because this organism is patented,Nakao Y, Kuno M. Method for the production of 5'-nucleotides. US Patent 3,652,395 (Mar 28 1972) it is not officially recognized as a legitimate Pseudomonas species, and therefore has no type strain. However, it is available through the American Type Culture Collection.
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CRC Press. Metabolism of propionate begins with its conversion to propionyl coenzyme A (propionyl-CoA), the usual first step in the metabolism of carboxylic acids. Since propanoic acid has three carbons, propionyl-CoA can directly enter neither beta oxidation nor the citric acid cycles. In most vertebrates, propionyl-CoA is carboxylated to D-methylmalonyl-CoA, which is isomerised to L-methylmalonyl-CoA.
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PLP is the active form of vitamin B6 (pyridoxine or pyridoxal). PLP is a versatile catalyst, acting as a coenzyme in a multitude of reactions, including decarboxylation, deamination and transamination. A number of pyridoxal-dependent enzymes involved in the metabolism of cysteine, homocysteine and methionine have been shown to be evolutionary related. These enzymes are tetrameric proteins of about 400 amino-acid residues.
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Glutamine-dependent NAD(+) synthetase is an enzyme that in humans is encoded by the NADSYN1 gene. Nicotinamide adenine dinucleotide (NAD) is a coenzyme in metabolic redox reactions, a precursor for several cell signaling molecules, and a substrate for protein posttranslational modifications. NAD synthetase (EC 6.3.5.1) catalyzes the final step in the biosynthesis of NAD from nicotinic acid adenine dinucleotide (NaAD).
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Ala84Thr) mutation, the most common mutation in the ETFDH gene, causes increased production of reactive oxygen species (ROS) and shortened neurites in cells expressing this mutant compared to wild type cells. Suberic acid, an accumulated intermediate metabolite in dehydrogenase deficiency, can significantly impair neurite outgrowth in NSC34 cells. This shortening of neurites can be restored by riboflavin, carnitine, or Coenzyme Q10 supplements.
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The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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Via metabolism, it becomes nicotinamide adenine dinucleotide NAD, a coenzyme which is involved in oxidation and reduction in metabolic cells. A deficiency of niacin leads to a disease called pellagra. Pyridoxine or vitamin B6, it becomes a major compound in the metabolism of amino acids. Pyrimidine is a heterocyclic amine that contains two nitrogen atoms in an unsaturated six-membered ring.
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The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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Allosteric regulation by metabolites. The regulation of the citric acid cycle is largely determined by product inhibition and substrate availability. If the cycle were permitted to run unchecked, large amounts of metabolic energy could be wasted in overproduction of reduced coenzyme such as NADH and ATP. The major eventual substrate of the cycle is ADP which gets converted to ATP.
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3,4-Dehydroadipyl-CoA semialdehyde dehydrogenase (NADP+) (, BoxD, 3,4-dehydroadipyl-CoA semialdehyde dehydrogenase) is an enzyme with systematic name 3,4-didehydroadipyl-CoA semialdehyde:NADP+ oxidoreductase. This enzyme catalyses the following chemical reaction : 3,4-didehydroadipyl-CoA semialdehyde + NADP+ \+ H2O \rightleftharpoons 3,4-didehydroadipyl-CoA + NADPH + H+ This enzyme catalyses a step in the aerobic benzoyl-coenzyme A catabolic pathway in Azoarcus evansii and Burkholderia xenovorans.
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The NADP+ structural site is located greater than 20Å away from the substrate binding site and the catalytic coenzyme NADP+ binding site. Its purpose in the enzyme catalyzed reaction has been unclear for many years. For some time, it was thought that NADP+ binding to the structural site was necessary for dimerization of the enzyme monomers. However, this was shown to be incorrect.
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Pantothenic acid is precursory to biosynthesis of coenzyme A (CoA), which is not only required for cellular respiration, but also serves a role in the synthesis of structural and functional brain cell components such as cholesterol, amino acids, fatty acids and phospholipids. Vitamin B5 also plays a more direct role in cognitive function by participating in the synthesis of steroid hormones and neurotransmitters.
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Pantethine (bis-pantethine or co-enzyme pantethine) is a dimeric form of pantetheine, which is produced from pantothenic acid (vitamin B5) by the addition of cysteamine. Pantethine was discovered by Gene Brown, a PhD student at the time. Pantethine is two molecules of pantetheine linked by a disulfide bridge. Pantetheine is an intermediate in the production of coenzyme A by the body.
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At this point, the lipoate-thioester functionality is translocated into the dihydrolipoyl transacetylase (E2) active site, where a transacylation reaction transfers the acetyl from the "swinging arm" of lipoyl to the thiol of coenzyme A. This produces acetyl-CoA, which is released from the enzyme complex and subsequently enters the citric acid cycle. E2 can also be known as lipoamide reductase-transacetylase.
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Vitamin B3 is highly absorbed from food sources such as beans, milk, meat, and eggs. It is also highly bioavailable from enriched flour, which has the non-coenzyme form referred to as "free" niacin. Cereal grains are not high sources of niacin. The U.S. population on average has an intake of niacin that is well above the recommended dietary allowance (RDA).
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Most transaminases are protein enzymes. However, some transamination activities of the ribosome have been found to be catalyzed by ribozymes (RNA enzymes). Examples being the hammerhead ribozyme, the VS ribozyme and the hairpin ribozyme. Transaminases require the coenzyme pyridoxal-phosphate, which is converted into pyridoxamine in the first half- reaction, when an amino acid is converted into a keto acid.
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Histone-based regulation of DNA transcription is also modified by acetylation. Acetylation is the reversible covalent addition of an acetyl group onto a lysine amino acid by the enzyme acetyltransferase. The acetyl group is removed from a donor molecule known as acetyl coenzyme A and transferred onto the target protein. Histones undergo acetylation on their lysine residues by enzymes known as histone acetyltransferase.
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The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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SAH riboswitches are a kind of riboswitch that bind S-adenosylhomocysteine (SAH). When the coenzyme S-adenosylmethionine (SAM) is used in a methylation reaction, SAH is produced. SAH riboswitches typically up-regulate genes involved in recycling SAH to create more SAM (or the metabolically related methionine). This is particularly relevant to cells, because high levels of SAH can be toxic.
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It could also result from the synthesis of a cystathionase that is so greatly mutated it cannot function at all. On the other hand, vitamin B6 – responsive form still has synthesis of cystathionase. However, the cystathionase has an altered ability to bind to vitamin B6, its coenzyme. This changed interaction lowers the efficiency of cystathionase, so it cannot convert cystathionine as well.
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These use MeB12 (methylcobalamin) form of the vitamin. # Dehalogenases #: Some species of anaerobic bacteria synthesize B12-dependent dehalogenases, which have potential commercial applications for degrading chlorinated pollutants. The microorganisms may either be capable of de novo corrinoid biosynthesis or are dependent on exogenous vitamin B12. In humans, two major coenzyme B12-dependent enzyme families corresponding to the first two reaction types, are known.
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HMG-CoA synthase contains an important catalytic cysteine residue that acts as a nucleophile in the first step of the reaction: the acetylation of the enzyme by acetyl-CoA (its first substrate) to produce an acetyl-enzyme thioester, releasing the reduced coenzyme A. The subsequent nucleophilic attack on acetoacetyl-CoA (its second substrate) leads to the formation of HMG-CoA.
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CTP is a high-energy molecule similar to ATP, but its role as an energy coupler is limited to a much smaller subset of metabolic reactions. CTP is a coenzyme in metabolic reactions like the synthesis of glycerophospholipids and glycosylation of proteins. CTP acts as an inhibitor of the enzyme aspartate carbamoyltransferase, which is used in pyrimidine biosynthesis.Blackburn, G. Michael.
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Isobutyryl-coenzyme A is a starting material for many natural products derived from Poly-Ketide Synthase (PKS) assembly lines, as well as PKS-NRPS hybrid assembly lines. These products can often be used as antibiotics. Notably, it is also an intermediate in the metabolism of the amino acid Valine, and structurally similar to intermediates in the catabolism of other small amino acids.
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Cytochrome bc1 with bound ubiquinone Azoxystrobin and other strobilurins inhibit mitochondrial respiration by blocking electron transport. They bind at the quinol outer binding site of the cytochrome b-c1 complex, where ubiquinone (coenzyme Q10) would normally bind when carrying electrons to that protein. Thus production of ATP is prevented. The generic name for this mode of action is "Quinone Outside Inhibitors" QoI.
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When bound to coenzyme A, it is central to the metabolism of carbohydrates and fats. The global demand for acetic acid is about 6.5 million metric tons per year (Mt/a), of which approximately 1.5 Mt/a is met by recycling; the remainder is manufactured from methanol. Vinegar is mostly dilute acetic acid, often produced by fermentation and subsequent oxidation of ethanol.
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Remethylation of homocysteine to methionine by MTR requires the derivative of cobalamin, methylcobalamin. Cobalamin metabolism is initiated by the endocytosis of cobalamin bound to the plasma protein transcobalamin (II). Cleavage of this complex produces free cobalamin, translocating from lysosome to cytoplasm. Conversion can occur to 5’-deoxyadenosylcobalamin (AdoCbl) activating the mitochrondrial enzyme methylmalonly coenzyme A mutase or to methylcobalamin (MeCbl).
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Pediatric Radiology, 40(3), 326–339. Leigh disease: Clinical and pathological symptoms usually appear in the first year of life and include psychomotor retardation and brain stem dysfunction. Bilaterally symmetric defects are seen in the periaqueductal grey matter, brain stem, basal ganglia, and dentate nucleus. Glutaric aciduria type 1 (GA1): An autosomal recessive disease, GA1 is due to glutaryl-coenzyme A dehydrogenase deficiency.
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The systematic name of this enzyme class is CoA-[4'-phosphopantetheine]:apo-[acyl-carrier-protein] 4'-pantetheinephosphotransferase. Other names in common use, disregarding the synthetase/synthase spelling difference, include acyl carrier protein holoprotein synthetase, holo-ACP synthetase, coenzyme A:fatty acid synthetase apoenzyme 4'-phosphopantetheine, acyl carrier protein synthetase (ACPS), PPTase, acyl carrier protein synthase, P-pant transferase, and CoA:apo-[acyl- carrier-protein] pantetheinephosphotransferase.
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Within little more than a decade, ryegrass and other weeds began to develop resistance. Australian farmers evolved again and began diversifying their techniques. In 1983, patches of ryegrass had become immune to Hoegrass, a family of herbicides that inhibit an enzyme called acetyl coenzyme A carboxylase. Ryegrass populations were large, and had substantial genetic diversity, because farmers had planted many varieties.
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Like many mitochondrial diseases, there is no cure for MERRF, no matter the means for diagnosis of the disease. The treatment is primarily symptomatic. High doses of Coenzyme Q10, B complex vitamins, and L-Carnitine are used for the altered metabolic processing that results in the disease. There is very little success with these treatments as therapies in hopes of improving mitochondrial function.
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The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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Solanesol possesses antimicrobial, anti-tumor, anti-inflammatory, and anti-ulcer activities, and it serves as an important pharmaceutical intermediate for the synthesis of coenzyme Q10, vitamin K2, and N-solanesyl-N,N′-bis(3,4-dimethoxybenzyl) ethylenediamine (SDB). The physiological functions of coenzyme Q10 include anti-oxidation, anti-aging, immune-function enhancement, cardiovascular enhancement, brain-function enhancement, and the regulation of blood lipids; it may be used for treating migraines, neurodegenerative diseases, hypertension, and cardiovascular diseases, and as a dietary supplement for patients with type 2 diabetes. Vitamin K2 promotes bone growth, inhibits bone resorption, stimulates bone mineralization, has preventive and therapeutic effects on osteoporosis, diminishes blood clotting, and reduces the progression of arteriosclerosis. The anti-cancer agent synergizer SDB allows P-glycoprotein-mediated multidrug resistance in cancer cells to be overcome, and has synergistic effects with certain anti-tumor drugs.
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In enzymology, an acetoacetyl-CoA reductase () is an enzyme that catalyzes the chemical reaction :(R)-3-hydroxyacyl-CoA + NADP+ \rightleftharpoons 3-oxoacyl- CoA + NADPH + H+ Thus, the two substrates of this enzyme are (R)-3-hydroxyacyl-CoA and NADP+, whereas its 3 products are 3-oxoacyl-CoA, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (R)-3-hydroxyacyl- CoA:NADP+ oxidoreductase. Other names in common use include acetoacetyl coenzyme A reductase, hydroxyacyl coenzyme-A dehydrogenase, NADP+-linked acetoacetyl CoA reductase, NADPH:acetoacetyl-CoA reductase, D(−)-beta- hydroxybutyryl CoA-NADP+ oxidoreductase, short chain beta- ketoacetyl(acetoacetyl)-CoA reductase, beta-ketoacyl-CoA reductase, D-3-hydroxyacyl-CoA reductase, and (R)-3-hydroxyacyl-CoA dehydrogenase. This enzyme participates in butanoate metabolism.
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In enzymology, a 3-hydroxy-2-methylbutyryl-CoA dehydrogenase () is an enzyme that catalyzes the chemical reaction :(2S,3S)-3-hydroxy-2-methylbutanoyl-CoA + NAD+ \rightleftharpoons 2-methylacetoacetyl-CoA + NADH + H+ Thus, the two substrates of this enzyme are (2S,3S)-3-hydroxy-2-methylbutanoyl-CoA and NAD+, whereas its 3 products are 2-methylacetoacetyl-CoA, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH- OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (2S,3S)-3-hydroxy-2-methylbutanoyl-CoA:NAD+ oxidoreductase. Other names in common use include 2-methyl-3-hydroxybutyryl coenzyme A dehydrogenase, 2-methyl-3-hydroxybutyryl coenzyme A dehydrogenase, and 2-methyl-3-hydroxy-butyryl CoA dehydrogenase. This enzyme participates in valine, leucine and isoleucine degradation.
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These diseases are inherited in a dominance relationship, as applies to most other genetic diseases. A variety of disorders can be caused by nuclear mutations of oxidative phosphorylation enzymes, such as coenzyme Q10 deficiency and Barth syndrome. Environmental influences may interact with hereditary predispositions and cause mitochondrial disease. For example, there may be a link between pesticide exposure and the later onset of Parkinson's disease.
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The inner membrane is a phospholipid bilayer that contains the complexes of oxidative phosphorylation. which contains the electron transport chain that is found on the cristae of the inner membrane and consists of four protein complexes and ATP synthase. These complexes are complex I (NADH:coenzyme Q oxidoreductase), complex II (succinate:coenzyme Q oxidoreductase), complex III (coenzyme Q: cytochrome c oxidoreductase), and complex IV (cytochrome c oxidase).
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The Rothia-sucC RNA motif is a conserved RNA structure that was discovered by bioinformatics. Rothia-sucC motif RNAs are found in the Actinobacterial genus Rothia. Rothia-sucC motif RNAs likely function as cis-regulatory elements, in view of their positions upstream of protein-coding genes. The presumably regulated genes encode Succinyl coenzyme A synthetase, which is a part of the citric acid cycle.
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A dehydrogenase (also called DH or DHase in the literature) is an enzyme belonging to the group of oxidoreductases that oxidizes a substrate by reducing an electron acceptor, usually NAD+/NADP+ or a flavin coenzyme such as FAD or FMN. They also catalyze the reverse reaction, for instance alcohol dehydrogenase not only oxidizes ethanol to acetaldehyde in animals but also produces ethanol from acetaldehyde in yeast.
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ALT catalyzes the transfer of an amino group from L-alanine to α-ketoglutarate, the products of this reversible transamination reaction being pyruvate and L-glutamate. :L-alanine + α-ketoglutarate ⇌ pyruvate + L-glutamate 600px ALT (and all aminotransferases) require the coenzyme pyridoxal phosphate, which is converted into pyridoxamine in the first phase of the reaction, when an amino acid is converted into a keto acid.
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3-Hydroxypropionaldehyde is formed by the condensation of acetaldehyde and formaldehyde. This reaction, when conducted in the gas-phase, was the basis for a now obsolete industrial route acrolein: :CH3CHO + CH2O → HOCH2CH2CHO :HOCH2CH2CHO → CH2=CHCHO + H2O Presently 3-hydroxypropionaldehyde is an intermediate in the production of pentaerythritol. Reuterin is an intermediate in the metabolism of glycerol to 1,3-propanediol catalysed by the coenzyme B12-dependent glycerol dehydratase.
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Generally, fluoroacetates are toxic because they are converted to fluorocitrate from fluoroacetyl coenzyme A. Fluorocitrate can inhibit aconitate hydratase, which is needed for the conversion of citrate, by competitive inhibition.Leong, L., Khan, S., Davis, C. K., Denman, S. E., & McSweeney, C. S. (2017). Fluoroacetate in plants - a review of its distribution, toxicity to livestock and microbial detoxification. Journal of animal science and biotechnology, 8, 55.
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In this pathway, the trans- cinnamic acid produced from L-phenylalanine is ligated to a Coenzyme A (CoA), just like the beginning of the beta-oxidative pathway. It then undergoes hydration at the double bond. This product then loses the CoA to produce benzaldehyde, an intermediate of the non-beta-oxidative pathway. Benzaldehyde is converted into benzoic acid and proceeds through the rest of the synthesis.
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Stearoyl-CoA is a coenzyme involved in the metabolism of fatty acids. Stearoyl-CoA is an 18-carbon long fatty acyl-CoA chain that participates in an unsaturation reaction. The reaction is catalyzed by the enzyme stearoyl-CoA desaturase, which is located in the endoplasmic reticulum. It forms a cis- double bond between the ninth and tenth carbons within the chain to form the product oleoyl-CoA.
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This results in the formation of formyl-H4MPT. :HCO-MF + H4MPT -> HCO-H4MPT + MF Formyl-H4MPT is subsequently reduced to methenyl-H4MPT. Methenyl-H4MPT then undergoes a one- step hydrolysis followed by a two-step reduction to methyl-H4MPT. The two-step reversible reduction is assisted by coenzyme F420 whose hydride acceptor spontaneously oxidizes. Once oxidized, F420’s electron supply is replenished by accepting electrons from H2.
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5,10-Methenyltetrahydrofolate (5,10-CH=THF) is a form of tetrahydrofolate that is an intermediate in metabolism. 5,10-CH=THF is a coenzyme that accepts and donates methenyl (CH=) groups. It is produced from 5,10-methylenetetrahydrofolate by either a NAD+ dependent methylenetetrahydrofolate dehydrogenase, or a NADP+ dependent dehydrogenase. It can also be produced as an intermediate in histidine catabolism, by formiminotransferase cyclodeaminase, from 5-formiminotetrahydrofolate.
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ATP citrate lyase is responsible for catalyzing the conversion of citrate and Coenzyme A (CoA) to acetyl-CoA and oxaloacetate, driven by hydrolysis of ATP. In the presence of ATP and CoA, citrate lyase catalyzes the cleavage of citrate to yield acetyl CoA, oxaloacetate, adenosine diphosphate (ADP), and orthophosphate (Pi): :citrate + ATP + CoA → oxaloacetate + Acetyl-CoA + ADP + Pi This enzyme was formerly given the EC number 4.1.3.8.
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Thus, the term "prosthetic group" is a very general one and its main emphasis is on the tight character of its binding to the apoprotein. It defines a structural property, with oppostion of the term "coenzyme" that defines a functional property. Prosthetic groups are a subset of cofactors. Loosely bound metal ions and coenzymes are still cofactors, but are generally not called prosthetic groups.
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Methylmalonic acidemia has an autosomal recessive pattern of inheritance. Methylmalonic acidemia is caused by a defect in the vitamin B12-dependent enzyme methylmalonyl CoA mutase. The inherited forms of methylmalonic acidemia cause defects in the metabolic pathway where methylmalonyl-coenzyme A (CoA) is converted into succinyl-CoA by the enzyme methylmalonyl-CoA mutase. Vitamin B12 is also needed for the conversion of methylmalonyl-CoA to Succinyl-CoA.
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Competitive inhibitors are commonly used to make pharmaceuticals. For example, methotrexate is a chemotherapy drug that acts as a competitive inhibitor. It is structurally similar to the coenzyme, folate, which binds to the enzyme dihydrofolate reductase. This enzyme is part of the synthesis of DNA and RNA, and when methotrexate binds the enzyme, it renders it inactive, so it cannot synthesize DNA and RNA.
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Lactate has long been considered a byproduct resulting from glucose breakdown through glycolysis during anaerobic metabolism. Glycolysis requires the coenzyme NAD+, and reduces it to NADH. As a means of regenerating NAD+ to allow glycolysis to continue, lactate dehydrogenase catalyzes the conversion of pyruvate to lactate in the cytosol, oxidizing NADH to NAD+. Lactate is then transported from the peripheral tissues to the liver.
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Arsenic's toxicity comes from the affinity of arsenic(III) oxides for thiols. Thiols, in the form of cysteine residues and cofactors such as lipoic acid and coenzyme A, are situated at the active sites of many important enzymes. Arsenic disrupts ATP production through several mechanisms. At the level of the citric acid cycle, arsenic inhibits lipoic acid, which is a cofactor for pyruvate dehydrogenase.
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As a sulfonamide antibiotic, sulfanilamide functions by competitively inhibiting (that is, by acting as a substrate analogue) enzymatic reactions involving para-aminobenzoic acid (PABA). PABA is needed in enzymatic reactions that produce folic acid, which acts as a coenzyme in the synthesis of purines and pyrimidines. Mammals do not synthesize their own folic acid so are unaffected by PABA inhibitors, which selectively kill bacteria.
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Here, cofactors were defined as an additional substance apart from protein and substrate that is required for enzyme activity and a prosthetic group as a substance that undergoes its whole catalytic cycle attached to a single enzyme molecule. However, the author could not arrive at a single all-encompassing definition of a "coenzyme" and proposed that this term be dropped from use in the literature.
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This enzyme belongs to the family of transferases, to be specific those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acetyl-CoA:carnitine O-acetyltransferase. Other names in common use include acetyl-CoA-carnitine O-acetyltransferase, acetylcarnitine transferase, carnitine acetyl coenzyme A transferase, carnitine acetylase, carnitine acetyltransferase, carnitine- acetyl-CoA transferase, and CATC. This enzyme participates in alanine and aspartate metabolism.
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Other processes regenerate ATP so that the human body recycles its own body weight equivalent in ATP each day. It is also a precursor to DNA and RNA, and is used as a coenzyme. From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the triphosphate.
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Approximately 90% of the metabolism of ethanol occurs in the liver. This occurs predominantly via the enzyme alcohol dehydrogenase, which transforms ethanol into its metabolite acetaldehyde (ethanal). Acetaldehyde is subsequently metabolized by the enzyme aldehyde dehydrogenase into acetate (ethanoate), which in turn is broken down into carbon dioxide and water. Acetate also combines with coenzyme A to form acetyl-CoA, and hence may participate in metabolic pathways.
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Reduction of coenzyme Q from its ubiquinone form (Q) to the reduced ubiquinol form (QH2). The electron transport chain carries both protons and electrons, passing electrons from donors to acceptors, and transporting protons across a membrane. These processes use both soluble and protein-bound transfer molecules. In mitochondria, electrons are transferred within the intermembrane space by the water-soluble electron transfer protein cytochrome c.
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Complex III ((EC 1.10.2.2)) (also referred to as cytochrome bc1 or the coenzyme Q : cytochrome c – oxidoreductase) is a proton pump driven by electron transport. Complex III is a multisubunit transmembrane protein encoded by both the mitochondrial (cytochrome b) and the nuclear genomes (all other subunits). Complex III is present in the inner mitochondrial membrane of all aerobic eukaryotes and the inner membranes of most eubacteria.
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Acyl-CoA dehydrogenase, C-2 to C-3 short chain is an enzyme that in humans is encoded by the ACADS gene. This gene encodes a tetrameric mitochondrial flavoprotein, which is a member of the acyl-CoA dehydrogenase family. This enzyme catalyzes the initial step of the mitochondrial fatty acid beta- oxidation pathway. The ACADS gene associated with short-chain acyl-coenzyme A dehydrogenase deficiency.
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Third, PEP carboxylase is significant in non-photosynthetic metabolic pathways. Figure 3 shows this metabolic flow (and its regulation). Similar to pyruvate carboxylase, PEP carboxylase replenishes oxaloacetate in the citric acid cycle. At the end of glycolysis, PEP is converted to pyruvate, which is converted to acetyl- coenzyme-A (acetyl-CoA), which enters the citric acid cycle by reacting with oxaloacetate to form citrate.
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The skin contains several antioxidants, including vitamin E, coenzyme Q10, ascorbate, carotenoids, superoxide dismutase, catalase, and glutathione peroxidase. These antioxidants provide protection from reactive oxygen species produced during normal cellular metabolism. However, overexposure to UV rays can lead to a significant reduction in the antioxidant supply, thus increasing oxidative stress. Hence, these antioxidants are essential in the skin's defense mechanism against UV radiation and photocarcinogenesis.
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Molecular structure of adenosine triphosphate (ATP) An ATP-binding motif is a 250-residue sequence within an ATP-binding protein’s primary structure. The binding motif is associated with a protein’s structure and/or function. ATP is a molecule of energy, and can be a coenzyme, involved in a number of biological reactions. ATP is proficient at interacting with other molecules through a binding site.
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Methylmalonic acid (MMA) (conjugate base methylmalonate) is a dicarboxylic acid that is a C-methylated derivative of malonate. The coenzyme A linked form of methylmalonic acid, methylmalonyl-CoA, is converted into succinyl-CoA by methylmalonyl-CoA mutase, in a reaction that requires vitamin B12 as a cofactor. In this way, it enters the Krebs cycle, and is thus part of one of the anaplerotic reactions.
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MTRR works by catalyzing the following chemical reaction: :2 [methionine synthase]-methylcob(I)alamin + 2 S-adenosylhomocysteine + NADP \rightleftharpoons 2 [methionine synthase]-cob(II)alamin + NADPH + H + 2 S-adenosyl-L-methionine The 3 products of this enzyme are methionine synthase- methylcob(I)alamin, S-adenosylhomocysteine, and NADP, whereas its 4 substrates are methionine synthase-cob(II)alamin, NADPH, H, and S-adenosyl-L-methionine. Scavenger Pathway of Methionine Synthase Reductase to Recover Inactivated Methionine Synthase Physiologically speaking, one crucial enzyme participated in the folate cycle is methionine synthase, which incorporated a coenzyme, cobalamin, also known as Vitamin B12. The coenzyme utilizes its cofactor, cobalt to catalyze the transferring function, in which the cobalt will switch between having 1 or 3 valence electrons, dubbed cob(I)alamin, and cob(III)alamin. Over time, the cob(I)alamin cofactor of methionine synthase becomes oxidized to cob(II)alamin, rendering the enzyme inactive.
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In enzymology, a [acetyl-CoA carboxylase] kinase () is an enzyme that catalyzes the chemical reaction :ATP + [acetyl-CoA carboxylase] \rightleftharpoons ADP + [acetyl-CoA carboxylase] phosphate Thus, the two substrates of this enzyme are ATP and acetyl-CoA carboxylase, whereas its two products are ADP and acetyl-CoA carboxylase phosphate. This enzyme belongs to the family of transferases, specifically those transferring a phosphate group to the sidechain oxygen atom of serine or threonine residues in proteins (protein-serine/threonine kinases). The systematic name of this enzyme class is ATP:[acetyl-CoA carboxylase] phosphotransferase. Other names in common use include acetyl coenzyme A carboxylase kinase (phosphorylating), acetyl-CoA carboxylase bound kinase, acetyl-CoA carboxylase kinase, acetyl-CoA carboxylase kinase (cAMP-independent), acetyl-CoA carboxylase kinase 2, acetyl-CoA carboxylase kinase-2, acetyl-CoA carboxylase kinase-3 (AMP- activated), acetyl-coenzyme A carboxylase kinase, ACK2, ACK3, AMPK, I-peptide kinase, and STK5.
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This step is coupled with ATP hydrolysis. # PPC is decarboxylated to 4′-phosphopantetheine by phosphopantothenoylcysteine decarboxylase (PPC-DC; CoaC) # 4′-Phosphopantetheine is adenylated (or more properly, AMPylated) to form dephospho-CoA by the enzyme phosphopantetheine adenylyl transferase (PPAT; CoaD) # Finally, dephospho-CoA is phosphorylated to coenzyme A by the enzyme dephosphocoenzyme A kinase (DPCK; CoaE). This final step requires ATP. Enzyme nomenclature abbreviations in parentheses represent eukaryotic and prokaryotic enzymes respectively.
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In Salmonella enterica, the bacterial sirtuin CobB regulates the activity of the enzyme acetyl-coenzyme A (acetyl-CoA) synthetase. As mentioned above, orthologs of acetyl-CoA synthetase exist in the cytoplasm (AceCS1) and in mitochondria (AceCS2) in mammals. The presence of the sirtuin deacetylase SIRT3 in the mitochondrial matrix suggests the existence of lysine acetylated mitochondrial proteins. Indeed, SIRT3 deacetylates and activates the mammalian mitochondrial acetyl-coA synthetase (AceCS2).
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Ribitol, or adonitol, is a crystalline pentose alcohol (C5H12O5) formed by the reduction of ribose. It occurs naturally in the plant Adonis vernalis as well as in the cell walls of some Gram-positive bacteria, in the form of ribitol phosphate, in teichoic acids. It also forms part of the chemical structure of riboflavin and flavin mononucleotide (FMN), which is a nucleotide coenzyme used by many enzymes, the so-called flavoproteins.
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Long-chain fatty acid transport protein 4 is a protein that in humans is encoded by the SLC27A4 gene. This membrane protein is also called FATP4 or ACSVL5 (very long chain fatty acyl-CoA synthetase 5). The purified protein shows enzyme activity (EC 6.2.1.3), esterifying long and very long chain fatty acids with Coenzyme A. It is debated whether it is also a fatty acid transporter at the plasma membrane.
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The mechanism for acetylation and deacetylation takes place on the NH3+ groups of lysine amino acid residues. These residues are located on the tails of histones that make up the nucleosome of packaged dsDNA. The process is aided by factors known as histone acetyltransferases (HATs). HAT molecules facilitate the transfer of an acetyl group from a molecule of acetyl-coenzyme A (Acetyl-CoA) to the NH3+ group on lysine.
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Mutations in UQCRB can result in mitochondrial deficiencies and associated disorders. It is majorly associated with a complex III deficiency, a deficiency in an enzyme complex which catalyzes electron transfer from coenzyme Q to cytochrome c in the mitochondrial respiratory chain. A complex III deficiency can result in a highly variable phenotype depending on which tissues are affected. Most frequent clinical manifestations include progressive exercise intolerance and cardiomyopathy.
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This provides significant resistance to 5′ exonucleases. Small nuclear RNAs contain unique 5′-caps. Sm- class snRNAs are found with 5′-trimethylguanosine caps, while Lsm-class snRNAs are found with 5′-monomethylphosphate caps. In bacteria, and potentially also in higher organisms, some RNAs are capped with NAD+, NADH, or 3′-dephospho- coenzyme A. In all organisms, mRNA molecules can be decapped in a process known as messenger RNA decapping.
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Stephen T. Sinatra (born 1946) is a board-certified cardiologist specializing in integrative medicine. He is also a certified bioenergetic psychotherapist.Sinatra ST. Heartbreak and Heart Disease (Keats Publishing 1996, 1999). He has published journal articles on cholesterol and coenzyme Q10. He has appeared on national radio and television broadcasts, including The Dr. Oz Show, The Doctors, CNN’s “Sunday Morning News,” XM Radio’s “America’s Doctor Dr. Mehmet Oz,” and PBS’s “Body & Soul.
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Cinnamic acid is then hydroxylated by membrane protein cinnamate-4-hydroxylase (C4H) to form p-coumaric acid. P-coumaric acid then acts as the starter unit which gets loaded with coenzyme A by 4-coumaroyl:CoA- ligase (4CL). The starter unit (A) then undergoes three iterations of malonyl- CoA resulting in (B), which enzymes chalcone synthase (CHS) and chalcone reductase (CHR) modify to obtain trihydroxychalcone. CHR is NADPH dependent.
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The esters of malonic acid are also used as a −CH2COOH synthon in the malonic ester synthesis. Additionally, the coenzyme A derivative of malonate, malonyl-CoA, is an important precursor in fatty acid biosynthesis along with acetyl CoA. Malonyl CoA is formed from acetyl CoA by the action of acetyl-CoA carboxylase, and the malonate is transferred to an acyl carrier protein to be added to a fatty acid chain.
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Pyridoxal phosphate (PLP, pyridoxal 5'-phosphate, P5P), the active form of vitamin B6, is a coenzyme in a variety of enzymatic reactions. The Enzyme commission has catalogued more than 140 PLP-dependent activities, corresponding to ~4% of all classified activities. The versatility of PLP arises from its ability to covalently bind the substrate, and then to act as an electrophilic catalyst, thereby stabilizing different types of carbanionic reaction intermediates.
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Structure of the coenzyme acetyl-CoA.The transferable acetyl group is bonded to the sulfur atom at the extreme left. Metabolism involves a vast array of chemical reactions, but most fall under a few basic types of reactions that involve the transfer of functional groups of atoms and their bonds within molecules. This common chemistry allows cells to use a small set of metabolic intermediates to carry chemical groups between different reactions.
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The active Nicotinamide group on the molecule NAD+ undergoes oxidation in many metabolic pathways. Nicotinamide, as a part of the coenzyme nicotinamide adenine dinucleotide (NADH / NAD+) is crucial to life. In cells, nicotinamide is incorporated into NAD+ and nicotinamide adenine dinucleotide phosphate (NADP+). NAD+ and NADP+ are coenzymes in a wide variety of enzymatic oxidation-reduction reactions, most notably glycolysis, the citric acid cycle, and the electron transport chain.
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As with other statins, atorvastatin is a competitive inhibitor of HMG-CoA reductase. Unlike most others, however, it is a completely synthetic compound. HMG-CoA reductase catalyzes the reduction of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) to mevalonate, which is the rate-limiting step in hepatic cholesterol biosynthesis. Inhibition of the enzyme decreases de novo cholesterol synthesis, increasing expression of low-density lipoprotein receptors (LDL receptors) on hepatocytes.
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Mutations in MT-CYB can result in mitochondrial deficiencies and associated disorders. It is majorly associated with a complex III deficiency, a deficiency in an enzyme complex which catalyzes electron transfer from coenzyme Q to cytochrome c in the mitochondrial respiratory chain. A complex III deficiency can result in a highly variable phenotype depending on which tissues are affected. Most frequent clinical manifestations include progressive exercise intolerance and cardiomyopathy.
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Umbelliferone Hydroxylation of cinnamic acid in the 4-position by trans-cinnamate 4-monooxygenase leads to p-coumaric acid, which can be further modified into hydroxylated derivatives such as umbelliferone. Another use of p-coumaric acid via its thioester with coenzyme A, i.e. 4-coumaroyl-CoA, is the production of chalcones. This is achieved with the addition of 3 malonyl-CoA molecules and their cyclization into a second phenyl group.
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The general structure, as well as several critical residues, on 6-phosphogluconate dehydrogenase appear to be well conserved over various species. The enzyme is a dimer, with each subunit containing three domains. The N-terminal coenzyme binding domain contains a Rossmann fold with additional α/β units. The second domain consists of a number of alpha helical structures, and the C-terminal domain consists of a short tail.
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Many metal cations are also required in the process. EDTA control and extensive cation presence/absence tests show that Ca(II), Mn(II), Cu(II) and Zn(II) are all essential in this process, probably functioning as a part of a coenzyme or prosthetic group. Mg(II) has partial effect, while Fe(II) and Fe(III) are inhibitory to some degree. Flagella are considered to contribute to pellicle formation.
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In collaboration with Samuel Gurin at the University of Pennsylvania, Brady discovered the enzyme system for the biosynthesis of long chain fatty acids,Brady RO, Gurin S. The biosynthesis of fatty acids by cell-free or water-soluble enzyme systems. J Biol Chem 1952; 199: 421–431 and later discovered the role of malonate coenzyme A in this process.Brady RO. Biosynthesis of fatty acids. II. Studies with enzymes from rat brain.
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Niacin and nicotinamide are both converted into the coenzyme NAD. NAD converts to NADP by phosphorylation in the presence of the enzyme NAD+ kinase. NAD and NADP are coenzymes for many dehydrogenases, participating in many hydrogen transfer processes. NAD is important in catabolism of fat, carbohydrate, protein, and alcohol, as well as cell signaling and DNA repair, and NADP mostly in anabolism reactions such as fatty acid and cholesterol synthesis.
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ESP15228, the (also) active metabolite Following oral intake, bempedoic acid reaches highest blood plasma concentrations after 3.5 hours. Food does not affect its absorption. When in the bloodstream, 99.3% of the substance are bound to plasma proteins. About a fifth of the substance is reversibly converted by an aldo-keto reductase enzyme to a metabolite (called ESP15228) that is also pharmacologically active in form of its coenzyme A–thioester.
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The Q-Symbio study was a multi-center randomized placebo- controlled double-blind clinical trial that was reported in the Journal of the American College of Cardiology: Heart Failure in September 2014. The purpose of the study was to assess the effect of the adjuvant therapy drug Coenzyme Q10 on several short-term and long-term endpoints in a total of 420 chronic heart failure patients enrolled in 17 cardiology centers in Europe, Asia, and Australia from 2003 to 2010. The trial name Q-SYMBIO reflects the focus on the following elements in the clinical trial: Q = Q10 and SYMBIO = SYMptoms, BIomarker status [Brain-Natriuretic Peptide], and long-term Outcome [hospitalizations/mortality]. Professor Mortensen and a team of researchers assigned 420 patients with moderate to severe chronic heart failure to Coenzyme Q10 100 milligrams three times daily or matching placebos in addition to the patients’ standard heart failure therapies for two years.
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An inactive enzyme without the cofactor is called an apoenzyme, while the complete enzyme with cofactor is called a holoenzyme. (Note that the International Union of Pure and Applied Chemistry (IUPAC) defines "coenzyme" a little differently, namely as a low-molecular-weight, non-protein organic compound that is loosely attached, participating in enzymatic reactions as a dissociable carrier of chemical groups or electrons; a prosthetic group is defined as a tightly bound, nonpolypeptide unit in a protein that is regenerated in each enzymatic turnover.) Some enzymes or enzyme complexes require several cofactors. For example, the multienzyme complex pyruvate dehydrogenase at the junction of glycolysis and the citric acid cycle requires five organic cofactors and one metal ion: loosely bound thiamine pyrophosphate (TPP), covalently bound lipoamide and flavin adenine dinucleotide (FAD), cosubstrates nicotinamide adenine dinucleotide (NAD+) and coenzyme A (CoA), and a metal ion (Mg2+). Organic cofactors are often vitamins or made from vitamins.
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Franz undertook research in many areas during his time at Monsanto. Some of his other chemistry research includes antiauxin chemistry (isothiazoles, isoxazoles, pyrazoles), plant chemistry, cell membrane chemistry (glyceride and phospholipid syntheses, liposomes), plant hormone chemistry (abscissic acid analogs, ethylene generators), and nitride sulfide chemistry. He also performed research pertaining to reaction mechanisms, coenzyme A antimetabolites, biorational design of herbicides, and periselective addition reactions of one- and threedipoles, as well as fundamental organic research.
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Biotin/lipoyl attachment domain has a conserved lysine residue that binds biotin or lipoic acid. Biotin plays a catalytic role in some carboxyl transfer reactions and is covalently attached, via an amide bond, to a lysine residue in enzymes requiring this coenzyme. Lipoamide acyltransferases have an essential cofactor, lipoic acid, which is covalently bound via an amide linkage to a lysine group. The lipoic acid cofactor is found in a variety of proteins.
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The protein encoded by this gene belongs to the ubiH/COQ6 family. It is an evolutionarily conserved monooxygenase required for the biosynthesis of coenzyme Q10 (or ubiquinone), which is an essential component of the mitochondrial electron transport chain, and one of the most potent lipophilic antioxidants implicated in the protection of cell damage by reactive oxygen species. knockdown of this gene in mouse and zebrafish results in decreased growth due to increased apoptosis.
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The significantly reduced mortality from heart disease associated with the combined Coenzyme Q10 and selenium treatment, compared to the placebo treatment, persisted during 12 years of follow-up. Professor Alehagen and his co-researchers carried out a number of sub-studies to investigate the mechanisms by which the combined supplementation reduced the risk of heart disease. They identified reduced bio-markers of oxidative stress, inflammation, and fibrosis as possible mechanisms explaining the study results.
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Biosynthesis of atropine starting from L-Phenylalanine The biosynthesis of atropine starting from l-phenylalanine first undergoes a transamination forming phenylpyruvic acid which is then reduced to phenyl-lactic acid. Coenzyme A then couples phenyl-lactic acid with tropine forming littorine, which then undergoes a radical rearrangement initiated with a P450 enzyme forming hyoscyamine aldehyde. A dehydrogenase then reduces the aldehyde to a primary alcohol making (−)-hyoscyamine, which upon racemization forms atropine.
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Pantothenate kinase 4 is an enzyme (pantothenate kinase) that in humans is encoded by the PANK4 gene. This gene encodes a protein belonging to the pantothenate kinase family. Pantothenate kinase is a key regulatory enzyme in the biosynthesis of coenzyme A (CoA) in bacteria and mammalian cells. It catalyzes the first committed step in the universal biosynthetic pathway leading to CoA and is itself subject to regulation through feedback inhibition by CoA.
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In enzymology, a formyl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :formyl-CoA + H2O \rightleftharpoons CoA + formate Thus, the two substrates of this enzyme are formyl-CoA and H2O, whereas its two products are CoA and formate. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is formyl-CoA hydrolase. This enzyme is also called formyl coenzyme A hydrolase.
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This variability suggests that SUCLA2 missense mutations may be associated with residual enzyme activity. Coenzyme Q10 and antioxidants have been used to treat mitochondrial DNA depletion syndrome but there is currently no evidence that these treatments result in clinical benefit. Mutations in the SUCLA2 gene leading to SUCLA2 deficiency result in Leigh's or a Leigh-like syndrome with onset of severe hypotonia, muscular atrophy, sensorineural hearing impairment, and often death in early childhood.
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Most ICLs that have been characterised to date contain only one domain (the catalytic domain). However, in the isoform 2 of _M. tuberculosis_ ICL, two domains were found. Through structural and kinetic studies, the C-terminal domain was found to be a regulatory domain, which dimerises with the corresponding C-terminal domain from another subunit (of the ICL2 tetramer) upon the binding of acetyl coenzyme A to activate the catalytic activity of the enzyme.
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In enzymology, a malonate CoA-transferase () is an enzyme that catalyzes the chemical reaction :acetyl-CoA + malonate \rightleftharpoons acetate + malonyl- CoA Thus, the two substrates of this enzyme are acetyl-CoA and malonate, whereas its two products are acetate and malonyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is acetyl-CoA:malonate CoA-transferase. This enzyme is also called malonate coenzyme A-transferase.
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Biosynthesis of the germicidin A,B, and C is achieved through a type III polyketide synthase called germicidin synthase (Gcs). Surugapyrone A is expected to be synthesized similarly utilizing a Gcs homolog. Gcs exhibits high substrate flexibility accepting a variety of acyl groups carried and transferred through a thioester bond by either coenzyme A (CoA) or acyl carrier protein (ACP). Catalytic efficiency is ten fold higher when ACP is the acyl carrier.
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The bioenhancer technology is primarily targeted for toxic drugs, expensive drugs, scarce drugs, poorly bioavailable drugs or drugs which need to be given for prolonged periods. However it can also be used in any drugs influenced by bioenhancers. The discovery and characterization of bioenhancers has led to several patent applications. Piperine is marketed as bioenhancer in mono preparations and as a component of dietary supplements that contain different vitamins, curcumin, resveratrol or Coenzyme Q10.
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He then joined the Wenner-Gren Institute (now the Wenner-Gren Foundation for Anthropological Research) in Stockholm with a fellowship from the Swedish Medical Research Council. Later at the Lister Institute in London he established the structure of several nucleotide coenzymes, in particular coenzyme A (CoA). He then attended Harvard with a Rockefeller fellowship. From 1954 to 1977 he was Professor of Organic Chemistry at King's College, University of Durham, now part of Newcastle University.
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The Kynurenine pathway. Quinolinic acid is a byproduct of the kynurenine pathway, which is responsible for catabolism of tryptophan in mammals. This pathway is important for its production of the coenzyme nicotinamide adenine dinucleotide (NAD+) and produces several neuroactive intermediates including quinolinic acid, kynurenine (KYN), kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), and 3-hydroxyanthranilic acid (3-HANA). Quinolinic acid's neuroactive and excitatory properties are a result of NMDA receptor agonism in the brain.
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The opening of the catalytic cleft is roughly correlated with distance between R516 and phosphates of ADP. In this way, ADP activates GLUD1 by facilitating the opening of the catalytic cleft which decreases product affinity and facilitates product release. thus allowing GLUD1 to reconcile the non-catalytic abortive complexes. Inhibition by high [ADP] has been suggested previously to be due to competition between ADP and the adenosine moiety of the coenzyme at the active site1.
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These shortening pathways also are likely to serve in inactivating 20-HETE, although the initial product of this shortening pathway, 20-carboxy-HETE, dilates coronary microvessels in the pig heart and thereby could serve to antagonize the vasoconstrictor actions of 20-HETE, at least in this organ and species. Coronary artery endothelial cells isolated from pigs incorporate 20-HETE primarily into the sn-2 position of phospholipids through a coenzyme A-dependent process.
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Since isovaleric acid acid and its esters are natural components of many foods, it is present in mammals including humans. Also, Isovaleryl-coenzyme A is an intermediate in the metabolism of branched- chain amino acids. Isovaleric acid is a major component of the cause of intense foot odor, as it is produced by skin bacteria metabolizing leucine and in rare cases a condition called isovaleric acidemia can lead to heightened levels of this metabolite.
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The main role of SDH is to create pyruvate that can be converted into free glucose. And glucagon gives the signal to repress gluconeogenesis and increase the amount of free glucose in the blood by releasing glycogen stores from the liver. Homocysteine, a compound that SDH combines with Serine to create cystathionine, also noncompetitively inhibits the action of SDH. Studies have shown that homocysteine reacts with SDH's PLP coenzyme to create a complex.
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The first is called a "prosthetic group", which consists of a coenzyme that is tightly or even covalently, and permanently bound to a protein. The second type of coenzymes are called "cosubstrates", and are transiently bound to the protein. Cosubstrates may be released from a protein at some point, and then rebind later. Both prosthetic groups and cosubstrates have the same function, which is to facilitate the reaction of enzymes and protein.
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The main purine-derived nucleobases. Aside from the crucial roles of purines (adenine and guanine) in DNA and RNA, purines are also significant components in a number of other important biomolecules, such as ATP, GTP, cyclic AMP, NADH, and coenzyme A. Purine (1) itself, has not been found in nature, but it can be produced by organic synthesis. They may also function directly as neurotransmitters, acting upon purinergic receptors. Adenosine activates adenosine receptors.
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NAD is also consumed by sirtuins, which are NAD-dependent deacetylases, such as Sir2. These enzymes act by transferring an acetyl group from their substrate protein to the ADP-ribose moiety of NAD; this cleaves the coenzyme and releases nicotinamide and O-acetyl-ADP-ribose. The sirtuins mainly seem to be involved in regulating transcription through deacetylating histones and altering nucleosome structure. However, non-histone proteins can be deacetylated by sirtuins as well.
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Nucleotides are made from amino acids, carbon dioxide and formic acid in pathways that require large amounts of metabolic energy. Consequently, most organisms have efficient systems to salvage preformed nucleotides. Purines are synthesized as nucleosides (bases attached to ribose). Both adenine and guanine are made from the precursor nucleoside inosine monophosphate, which is synthesized using atoms from the amino acids glycine, glutamine, and aspartic acid, as well as formate transferred from the coenzyme tetrahydrofolate.
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In phenylalanine hydroxylase over 300 different mutations throughout the structure cause phenylketonuria. Phenylalanine substrate and tetrahydrobiopterin coenzyme in black, and Fe2+ cofactor in yellow. () Since the tight control of enzyme activity is essential for homeostasis, any malfunction (mutation, overproduction, underproduction or deletion) of a single critical enzyme can lead to a genetic disease. The malfunction of just one type of enzyme out of the thousands of types present in the human body can be fatal.
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Steric hindrance is the major limiting factor in the synthesis of the coenzyme analogs. For example, no reaction occurs between neopentyl chloride and , whereas the secondary alkyl halide analogs are too unstable to be isolated. This effect may be due to the strong coordination between benzimidazole and the central cobalt atom, pulling it down into the plane of the corrin ring. The trans effect determines the polarizability of the Co–C bond so formed.
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It catalyzes the reduction of cytochrome c by oxidation of coenzyme Q (CoQ) and the concomitant pumping of 4 protons from the mitochondrial matrix to the intermembrane space: : QH2 \+ 2 cytochrome c (FeIII) + 2 H → Q + 2 cytochrome c (FeII) + 4 H In the process called Q cycle, two protons are consumed from the matrix (M), four protons are released into the inter membrane space (IM) and two electrons are passed to cytochrome c.
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The enzyme catalyzes the reaction: Acetyl-CoA + n malonyl-CoA + 4n NADPH + 4n H+ \rightleftharpoons long-chain-acyl-CoA + n CoA + n CO2 \+ 4n NADP+ The 4 substrates of this enzyme are acetyl-CoA, malonyl-CoA, NADPH, and H+, whereas its 4 products are Acyl-CoA, CoA, CO2, and NADP+. More specifically, the FAS catalysis mechanism consumes an acetyl-coenzyme A (acetyl-CoA) and seven malonyl-CoA molecules to produce a Palmitoyl-CoA.
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In oxidation-reduction reactions, the active part of the coenzyme is the nicotinamide. In NAD+, the nitrogen in the aromatic nicotinamide ring is covalently bonded to adenine dinucleotide. The formal charge on the nitrogen is stabilized by the shared electrons of the other carbon atoms in the aromatic ring. When a hydride atom is added onto NAD+ to form NADH, the molecule loses its aromaticity, and therefore a good amount of stability.
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This final step also requires ATP. This pathway is suppressed by end-product inhibition, meaning that CoA is a competitive inhibitor of pantothenate kinase, the enzyme responsible for the first step. Coenzyme A is necessary in the reaction mechanism of the citric acid cycle. This process is the body's primary catabolic pathway and is essential in breaking down the building blocks of the cell such as carbohydrates, amino acids and lipids, for fuel.
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The mitochondrial cytochrome b is fundamental for the assembly and function of Complex III of the mitochondrial respiratory chain. Complex III is responsible for the catalysis of electron transfer from coenzyme Q to cytochrome c in the mitochondrial respiratory chain by translocating protons concomitantly across the inner membrane of the mitochondria. The transfer of electrons then contributes to the generation of a proton gradient across the mitochondrial membrane that is then used for ATP synthesis.
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The glyoaxalase system consists of two enzymes, glyoxalase I and glyoxalase II. The former enzyme, described here, rearranges the hemithioacetal formed naturally by the attack of glutathione on methylglyoxal into the product. Glyoxalase II hydrolyzes the product to re-form the glutathione and produce D-lactate. Thus, glutathione acts unusually as a coenzyme and is required only in catalytic (i.e., very small) amounts; normally, glutathione acts instead as a redox couple in oxidation-reduction reactions.
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Uridine diphosphate N-acetylglucosamine or UDP-GlcNAc is a nucleotide sugar and a coenzyme in metabolism. It is used by glycosyltransferases to transfer N-acetylglucosamine residues to substrates. D-Glucosamine is made naturally in the form of glucosamine-6-phosphate, and is the biochemical precursor of all nitrogen-containing sugars. To be specific, glucosamine-6-phosphate is synthesized from fructose 6-phosphate and glutamine as the first step of the hexosamine biosynthesis pathway.
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The pioneer company in this field is Prolong Pharmaceuticals which has developed a PEGylated erythropoietin (PEG-EPO). Oligonucleotides are a third category of big molecules. They are oligomers of nucleotides, which in turn are composed of a five-carbon sugar (either ribose or desoxyribose), a nitrogenous base (either a pyrimidine or a purine) and 1–3 phosphate groups. The best known representative of a nucleotide is the coenzyme ATP (=Adenosine triphosphate), MW 507.2.
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An off-target effect has been demonstrated at high concentrations of etomoxir on Coenzyme-A (CoA) metabolism. A double-blind crossover study in human adult males showed that treatment with etomoxir enhanced feelings of hunger and increased meal portion size by 22%. Etomoxir has been reported to decrease the incorporation of palmitic acid and oleic acid into cardiolipin, although it does not affect the activities of cardiolipin biosynthesis and remodeling. Etomoxir has off-target effects.
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Flavoproteins were first discovered in 1879 by separating components of cow's milk. They were initially called lactochrome due to their milky origin and yellow pigment. It took 50 years for the scientific community to make any substantial progress in identifying the molecules responsible for the yellow pigment. The 1930s launched the field of coenzyme research with the publication of many flavin and nicotinamide derivative structures and their obligate roles in redox catalysis.
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Salutaridinol is a product of the enzyme salutaridine: NADPH 7-oxidoreductase and the substrate for the enzyme salutaridinol 7-O-acetyltransferase, which are two of the four enzymes in the morphine biosynthesis pathway that generates morphine from (R)-reticuline.Lenz, Rainer, and Meinhart H. Zenk. "Acetyl coenzyme A: salutaridinol-7-O-acetyltransferase from Papaver somniferum plant cell cultures: The enzyme catalyzing the formation of thebaine in morphine biosynthesis." Journal of Biological Chemistry 270.52 (1995): 31091-31096.
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Crystal structures for the E. coli SCS provide evidence that the coenzyme A binds within each α-subunit (within a Rossmann fold) in close proximity to a histidine residue (His246α). This histidine residue becomes phosphorylated during the succinate forming step in the reaction mechanism. The exact binding location of succinate is not well-defined. The formation of the nucleoside triphosphate occurs in an ATP grasp domain, which is located near the N-terminus of the each β subunit.
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The Q-Symbio study was an international multi-center clinical trial that was reported in the Journal of the American College of Cardiology: Heart Failure in September 2014. Professor Mortensen and a team of researchers enrolled 420 patients with moderate to severe chronic heart failure. Half of the patients received a Coenzyme Q10 treatment of 100 milligrams three times daily for two years. The other half of the patients got inactive placebo capsules daily for two years.
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As the mitochondrial matrix is where the TCA cycle takes place, different metabolites are commonly confined to the mitochondria. Upon ageing, mitochondrial function declines, allowing escape of these metabolites, which can induce epigenetic changes, associated with ageing. TCA cycle Acetyl-coenzyme A (Acetyl-CoA) enters the TCA cycle in the mitochondrial matrix, and is oxidized in the process of energy production. Upon escaping the mitochondria and entering the nucleus, it can act as a substrate for histone acetylation.
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In enzymology, a (S)-methylmalonyl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :(S)-methylmalonyl-CoA + HO \rightleftharpoons methylmalonate + CoA Thus, the two substrates of this enzyme are (S)-methylmalonyl-CoA and HO, whereas its two products are methylmalonate and CoA. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is (S)-methylmalonyl-CoA hydrolase. This enzyme is also called D-methylmalonyl- coenzyme A hydrolase.
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HLCS (holocarboxylase synthetase (biotin-(propionyl-Coenzyme A-carboxylase (ATP-hydrolysing)) ligase)) is a family of enzymes (). This enzyme is important for the effective use of biotin, a B vitamin found in foods such as liver, egg yolks, and milk. In many of the body's tissues, holocarboxylase synthetase activates other specific enzymes (called biotin-dependent carboxylases) by attaching biotin to them. These carboxylases are involved in many critical cellular functions, including the production and breakdown of proteins, fats, and carbohydrates.
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At room temperature, about 76% of -ribose is present in pyranose forms (α:β = 1:2) and 24% in the furanose forms (α:β = 1:3), with only about 0.1% of the linear form present. The ribonucleosides adenosine, cytidine, guanosine, and uridine are all derivatives of β\--ribofuranose. Metabolically-important species that include phosphorylated ribose include ADP, ATP, coenzyme A, and NADH. cAMP and cGMP serve as secondary messengers in some signaling pathways and are also ribose derivatives.
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5: cysteamine. Coenzyme A was identified by Fritz Lipmann in 1946, who also later gave it its name. Its structure was determined during the early 1950s at the Lister Institute, London, together by Lipmann and other workers at Harvard Medical School and Massachusetts General Hospital. Lipmann initially intended to study acetyl transfer in animals, and from these experiments he noticed a unique factor that was not present in enzyme extracts but was evident in all organs of the animals.
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Coenzyme A is naturally synthesized from pantothenate (vitamin B5), which is found in food such as meat, vegetables, cereal grains, legumes, eggs, and milk. In humans and most living organisms, pantothenate is an essential vitamin that has a variety of functions. In some plants and bacteria, including Escherichia coli, pantothenate can be synthesised de novo and is therefore not considered essential. These bacteria synthesize pantothenate from the amino acid aspartate and a metabolite in valine biosynthesis.
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Mutations in this gene result in trifunctional protein deficiency or long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency. The most common form of the mutation is G1528C, in which the guanine at the 1528th position is changed to a cytosine. The gene mutation creates a protein deficiency that is associated with impaired oxidation of long-chain fatty acids that can lead to sudden infant death. Clinical manifestations of this deficiency can include myopathy, cardiomyopathy, episodes of coma, and hypoglycemia.
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Long-chain L-3-hydroxyacyl-coenzyme A dehydrogenase deficiency is associated with some pregnancy-specific disorders, including preeclampsia, HELLP syndrome (hemolysis, elevated liver enzymes, low platelets), hyperemesis gravidarum, acute fatty liver of pregnancy, and maternal floor infarct of the placenta. Additionally, it has been correlated with Acute fatty liver of pregnancy (AFLP) disease. From a clinical perspective, HADHA might also be a useful marker to predict resistance to certain types of chemotherapy in patients with lung cancer.
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Pyruvate is an important chemical compound in biochemistry. It is the output of the metabolism of glucose known as glycolysis. One molecule of glucose breaks down into two molecules of pyruvate, which are then used to provide further energy, in one of two ways. Pyruvate is converted into acetyl-coenzyme A, which is the main input for a series of reactions known as the Krebs cycle (also known as the citric acid cycle or tricarboxylic acid cycle).
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Pyruvate from glycolysis is converted by fermentation to lactate using the enzyme lactate dehydrogenase and the coenzyme NADH in lactate fermentation, or to acetaldehyde (with the enzyme pyruvate decarboxylase) and then to ethanol in alcoholic fermentation. Pyruvate is a key intersection in the network of metabolic pathways. Pyruvate can be converted into carbohydrates via gluconeogenesis, to fatty acids or energy through acetyl- CoA, to the amino acid alanine, and to ethanol. Therefore, it unites several key metabolic processes.
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By disrupting an acyl- coenzyme A (CoA) thioesterase gene, Sabirova and colleagues were able to mutate the organism to hyper-produce polyhydroxyalkanoates (PHA). They were then able to recover the large amounts of PHA that were released by mutant Alcanivorax from the culture mediums with relative ease. Before, costly and environmentally dangerous solvents had to be used in order to retrieve PHA from intracellular granules. This allows for production of environmentally friendly polymers in factories that utilized mutant Alcanivorax.
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Mutations in this gene cause one form of familial hyperinsulinemic hypoglycemia. A deficiency is associated with 3-hydroxyacyl- coenzyme A dehydrogenase deficiency. Mutations also cause 3-hydroxyacyl-CoA dehydrogenase deficiency. There are a wide variety of mutations that have been identified to cause this disease. Among them are missense mutations (A40T, P258L, D57G, Y226H) and nonsense mutations (R236X) in the protein, and splicing mutations (261+1G>A, 710-2A>G) and some small deletions (587delC) in the cDNA.
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Vitamin B12 (cobalamins) contain a corrin ring similar in structure to porphyrin and is an essential coenzyme for the catabolism of fatty acids as well for the biosynthesis of methionine. DNA and RNA which store and transmit genetic information are composed of nucleic acid primary metabolites. First messengers are signaling molecules that control metabolism or cellular differentiation. These signaling molecules include hormones and growth factors in turn are composed of peptides, biogenic amines, steroid hormones, auxins, gibberellins etc.
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It's a keto acid, formed during the oxidative decarboxylation of isocitrate to alpha-ketoglutarate, which is catalyzed by the enzyme isocitrate dehydrogenase. Isocitrate is first oxidized by coenzyme NAD+ to form oxalosuccinic acid/oxalosuccinate. Oxalosuccinic acid is both an alpha-keto and a beta-keto acid (an unstable compound) and it is the beta-ketoic property that allows the loss of carbon dioxide in the enzymatic reaction in conversion to the five-carbon molecule 2-oxoglutarate.
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Mysore Ananthamurthy Viswamitra (1932–2001) was an Indian molecular biophysicist and crystallographer, known for his pioneering work on the X-Ray structural studies of DNA fragments and nucleotide coenzyme molecules. His work is reported to have assisted in the development of the concept of sequence-dependent oligonucleotide conformation. He was an INSA senior scientist and an MSIL chair professor of physics at the Indian Institute of Science and a visiting professor at the University of Cambridge.
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Biogenetic precursor of all indole alkaloids is the amino acid tryptophan. For most of them, the first synthesis step is decarboxylation of tryptophan to form tryptamine. Dimethyltryptamine (DMT) is formed from tryptamine by methylation with the participation of coenzyme of S-adenosyl methionine (SAM). Psilocin is produced by spontaneous dephosphorylation of psilocybin. In the biosynthesis of serotonin, the intermediate product is not tryptamine but 5-hydroxytryptophan, which is in turn decarboxylated to form 5-hydroxytryptamine (serotonin).
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A minimal presence of cobalt in soils therefore markedly improves the health of grazing animals, and an uptake of 0.20 mg/kg a day is recommended because they have no other source of vitamin B. Proteins based on cobalamin use corrin to hold the cobalt. Coenzyme B12 features a reactive C-Co bond that participates in the reactions. In humans, B12 has two types of alkyl ligand: methyl and adenosyl. MeB12 promotes methyl (−CH3) group transfers.
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NADH in solution has an emission peak at 340 nm and a fluorescence lifetime of 0.4 nanoseconds, while the oxidized form of the coenzyme does not fluoresce. The properties of the fluorescence signal changes when NADH binds to proteins, so these changes can be used to measure dissociation constants, which are useful in the study of enzyme kinetics. These changes in fluorescence are also used to measure changes in the redox state of living cells, through fluorescence microscopy.
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In healthy mammalian tissues, estimates of the ratio between free NAD and NADH in the cytoplasm typically lie around 700:1; the ratio is thus favourable for oxidative reactions. The ratio of total NAD/NADH is much lower, with estimates ranging from 3–10 in mammals. In contrast, the NADP/NADPH ratio is normally about 0.005, so NADPH is the dominant form of this coenzyme. These different ratios are key to the different metabolic roles of NADH and NADPH.
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The structure of cyclic ADP- ribose. Another function of this coenzyme in cell signaling is as a precursor of cyclic ADP-ribose, which is produced from NAD by ADP-ribosyl cyclases, as part of a second messenger system. This molecule acts in calcium signaling by releasing calcium from intracellular stores. It does this by binding to and opening a class of calcium channels called ryanodine receptors, which are located in the membranes of organelles, such as the endoplasmic reticulum.
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Arthur Harden, co-discoverer of NAD The coenzyme NAD was first discovered by the British biochemists Arthur Harden and William John Young in 1906. They noticed that adding boiled and filtered yeast extract greatly accelerated alcoholic fermentation in unboiled yeast extracts. They called the unidentified factor responsible for this effect a coferment. Through a long and difficult purification from yeast extracts, this heat- stable factor was identified as a nucleotide sugar phosphate by Hans von Euler-Chelpin.
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This is the committed step in CoA biosynthesis and requires ATP. # A cysteine is added to 4′-phosphopantothenate by the enzyme phosphopantothenoylcysteine synthetase to form 4'-phospho-N- pantothenoylcysteine (PPC). This step is coupled with ATP hydrolysis. # PPC is decarboxylated to 4′-phosphopantetheine by phosphopantothenoylcysteine decarboxylase # 4′-Phosphopantetheine is adenylated (or more properly, AMPylated) to form dephospho-CoA by the enzyme phosphopantetheine adenylyl transferase # Finally, dephospho-CoA is phosphorylated to coenzyme A by the enzyme dephosphocoenzyme A kinase.
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All statins act by inhibiting 3-hydroxy-3-methylglutaryl (HMG) coenzyme A reductase. HMG-CoA reductase, the rate-limiting enzyme of the HMG-CoA reductase pathway, the metabolic pathway responsible for the endogenous production of cholesterol. Statins are more effective than other lipid- regulating drugs at lowering LDL-cholesterol concentration, but they are less effective than the fibrates in reducing triglyceride concentration. However, statins reduce cardiovascular disease events and total mortality irrespective of the initial cholesterol concentration.
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The process in which they move into the mitochondria is called the carnitine shuttle. Long chain FA are first activated via esterification with coenzyme A to produce a fatty acid-coA complex which can then cross the external mitochondrial border. The co-A is then exchanged with carnitine (via the enzyme carnitine palmitoyltransferase I) to produce a fatty acid-carnitine complex. This complex is then transported through the inner mitochondrial membrane via a transporter protein called carnitine-acylcarnitine translocase.
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N-myristoyltransferase (NMT) catalyzes the reaction of N-terminal myristoylation of many signaling proteins. It transfers myristic acid from myristoyl coenzyme A to the amino group of a protein's N-terminal glycine residue. Biochemical evidence indicates the presence of several distinct NMTs, varying in apparent molecular weight and /or subcellular distribution. The 496-amino acid of human NMT2 protein shares 77% and 96% sequence identity with human NMT1 and mouse Nmt2 comprise two distinct families of N-myristoyltransferases.
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In 1929, Euler-Chelpin and Arthur Harden received the Nobel Prize in chemistry for research on alcoholic fermentation of carbohydrates and the role of enzymes. Arthur Harden dealt only with the chemical effects of bacteria from 1903 with alcoholic fermentation. Harden discovered that the enzyme zymase, discovered by Eduard Buchner, only produces fermentation in interaction with the coenzyme cozymase. Euler-Chelpin, in turn, convincingly described what happens in sugar fermentation and the action of fermentation enzymes using physical chemistry.
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It is an important intermediate in the citric acid cycle, where it is synthesized from α-ketoglutarate by α-ketoglutarate dehydrogenase through decarboxylation. During the process, coenzyme A is added. With B12 as an enzymatic cofactor, it is also synthesized from propionyl CoA, the odd-numbered fatty acid, which cannot undergo beta- oxidation. Propionyl-CoA is carboxylated to D-methylmalonyl-CoA, isomerized to L-methylmalonyl-CoA, and rearranged to yield succinyl-CoA via a vitamin B12-dependent enzyme.
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In enzymology, an isobutyryl-CoA mutase () is an enzyme that catalyzes the chemical reaction :2-methylpropanoyl-CoA \rightleftharpoons butanoyl-CoA Hence, this enzyme has one substrate, 2-methylpropanoyl-CoA, and one product, butanoyl-CoA. This enzyme belongs to the family of isomerases, specifically those intramolecular transferases transferring other groups. The systematic name of this enzyme class is 2-methylpropanoyl-CoA CoA-carbonylmutase. Other names in common use include isobutyryl coenzyme A mutase, and butyryl- CoA:isobutyryl-CoA mutase.
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3'-Phosphoadenosine-5'-phosphosulfate (PAPS) is a derivative of adenosine monophosphate that is phosphorylated at the 3' position and has a sulfate group attached to the 5' phosphate. It is the most common coenzyme in sulfotransferase reactions. It is endogenously synthesized by organisms via the phosphorylation of adenosine 5'-phosphosulfate (APS), an intermediary metabolite. In humans such reaction is performed by bifunctional 3'-phosphoadenosine 5'-phosphosulfate synthases (PAPSS1 and PAPSS2) using ATP as the phosphate donor.
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The coenzyme NAD and its derivatives are involved in hundreds of metabolic redox reactions and are utilized in protein ADP-ribosylation, histone deacetylation, and in some Ca2+ signaling pathways. NMNAT (EC 2.7.7.1) is a central enzyme in NAD biosynthesis, catalyzing the condensation of nicotinamide mononucleotide (NMN) or nicotinic acid mononucleotide (NaMN) with the AMP moiety of ATP to form NAD or NaAD. NMNAT1 is the most widely expressed of three orthologous genes with nicotinamide-nucleotide adenylyltransferase (NMNAT) activity.
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The enzyme consists of 277 amino acid residues and is widely distributed in human tissues such as liver, epidermis, stomach, small intestine, kidney, neuronal cells, and smooth muscle fibers. The best substrates of CBR1 are quinones, including ubiquinone-1 and tocopherolquinone (vitamin E). Ubiquinones (coenzyme Q) are constitutive parts of the respiratory chain, and tocopherolquinone protects lipids of biological membranes against lipid peroxidation, indicating that CBR1 may play an important role as an oxidation–reduction catalyst in biological processes.
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Peroxisomal acyl-coenzyme A oxidase 1 is an enzyme that in humans is encoded by the ACOX1 gene. The protein encoded by this gene is the first enzyme of the fatty acid beta-oxidation pathway, which catalyzes the desaturation of acyl- CoAs to 2-trans-enoyl-CoAs. It donates electrons directly to molecular oxygen, thereby producing hydrogen peroxide. Defects in this gene result in pseudoneonatal adrenoleukodystrophy, a disease that is characterized by accumulation of very long chain fatty acids.
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Other cofactors, such as ATP and coenzyme A, were discovered later in the 1900s. The mechanism of cofactor activity was discovered when, Otto Heinrich Warburg determined in 1936 that NAD+ functioned as an electron acceptor. Well after these initial discoveries, scientists began to realize that the manipulation of cofactor concentrations could be used as tools for the improvement of metabolic pathways. An important group of organic cofactors is the family of molecules referred to as vitamins.
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Unusually, these reactions carried out by the glyoxalase system does not oxidize glutathione, which usually acts as a redox coenzyme. Although aldose reductase can also detoxify methylglyoxal, the glyoxalase system is more efficient and seems to be the most important of these pathways. Glyoxalase I is an attractive target for the development of drugs to treat infections by some parasitic protozoa, and cancer. Several inhibitors of glyoxalase I have been identified, such as S-(N-hydroxy-N-methylcarbamoyl)glutathione.
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Several proteins from prokaryotes and archaea are also modified by N-terminal acetylation. N-terminal Acetylation is catalyzed by a set of enzyme complexes, the N-terminal acetyltransferases (NATs). NATs transfer an acetyl group from acetyl-coenzyme A (Ac-CoA) to the α-amino group of the first amino acid residue of the protein. Different NATs are responsible for the acetylation of nascent protein N-terminal, and the acetylation was found to be irreversible so far.
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LOV-domains are a sub- class of PAS domains and were first identified in plants as part of Phototropin, which plays an essential role in the plant's growth towards light. They noncovalently bind Flavin mononucleotide (FMN) as coenzyme. Due to the bound FMN LOV-domains exhibit an intrinsic fluorescence, which is however very weak. Upon illumination with blue light, LOV-domains undergo a photocyle, during which a covalent bond is formed between a conserved cysteine-residue and the FMN.
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It reduces total blood cholesterol by blocking the action of 3-hydroxy-3-methyl-glutaryl-coenzyme-A (HMG-CoA) reductase, an enzyme in the liver involved in the production of cholesterol. As the liver needs cholesterol to produce bile, the reduced blood cholesterol level causes the liver cells to produce receptors that draw cholesterol from the blood, reducing its level even further. The cholesterol drawn out of the blood in this way is the LDL cholesterol.
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The ACSL1 gene is located on the 4th chromosome, with its specific location being 4q35.1. The gene contains 28 exons. The protein encoded by this gene is an isozyme of the long-chain fatty- acid-coenzyme A ligase family. Although differing in substrate specificity, subcellular localization, and tissue distribution, all isozymes of this family convert free long-chain fatty acids into fatty acyl-CoA esters, and thereby play a key role in lipid biosynthesis and fatty acid degradation.
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NADH:ubiquinone oxidoreductase (complex I) catalyzes the transfer of electrons from NADH to ubiquinone (coenzyme Q) in the first step of the mitochondrial respiratory chain, resulting in the translocation of protons across the inner mitochondrial membrane. The NDUFAF2 gene encodes a complex I assembly factor, B17.2L, that is important for the correct function of the mitochondrial respiratory chain. Specifically, B17.2L acts as a molecular chaperone, associating with an 830 kDa subassembly in the late stages of complex I assembly.
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In enzymology, an itaconyl-CoA hydratase () is an enzyme that catalyzes the chemical reaction :citramalyl-CoA \rightleftharpoons itaconyl-CoA + H2O Hence, this enzyme has one substrate, citramalyl-CoA, and two products, itaconyl-CoA and H2O. This enzyme belongs to the family of lyases, specifically the hydro- lyases, which cleave carbon-oxygen bonds. The systematic name of this enzyme class is citramalyl-CoA hydro-lyase (itaconyl-CoA-forming). Other names in common use include itaconyl coenzyme A hydratase, and citramalyl-CoA hydro- lyase.
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The addition of the myristoyl group proceeds via a nucleophilic addition-elimination reaction. First, myristoyl coenzyme A (CoA) is positioned in its binding pocket of NMT so that the carbonyl faces two amino acid residues, phenylalanine 170 and leucine 171. This polarizes the carbonyl so that there is a net positive charge on the carbon, making it susceptible to nucleophilic attack by the glycine residue of the protein to be modified. When myristoyl CoA binds, NMT reorients to allow binding of the peptide.
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Like other antioxidants, it functions by ridding the body of harmful free radicals that can cause damage to tissues and organs. It has an important role in the Krebs cycle as a coenzyme leading to the production of antioxidants, intracellular glutathione, and nerve-growth factors. Animal research has also uncovered the ability of ALA to improve nerve conduction velocity. Because flavors are perceived by differences in electric potential through specific nerves innervating the tongue, idiopathic dysgeusia may be a form of a neuropathy.
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Other different types of annonin-based insecticides, derived from A. mucosa, fight off lepidopteran (moth) pests that infest cabbage leaves, also found in the tropical climates of Brazil. The benefit of using these bioinsecticides is their relatively low cost and no phytotoxicity. These annonin molecules act as overpowering inhibitors of complex I (NADH: ubiquinone oxidoreductase) in the electron-transport chain in the mitochondria of quarry pests. In cell membranes of these same pests, annonins also inhibit coenzyme NADH, causing these arthropods to die.
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Pantothenate kinase 1 is an enzyme that in humans is encoded by the PANK1 gene. This gene encodes a protein belonging to the pantothenate kinase family, which in mammals is made of up PANK1, PANK2, PANK3, and PANK4. Pantothenate kinase is a key regulatory enzyme in the biosynthesis of coenzyme A (CoA) in bacteria and mammalian cells. It catalyzes the first committed step in the universal biosynthetic pathway leading to CoA and is itself subject to regulation through feedback inhibition by CoA.
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In all living organisms, coenzyme A is synthesized in a five-step process that requires four molecules of ATP, pantothenate and cysteine (see figure): Details of the biosynthetic pathway of CoA synthesis from pantothenic acid. # Pantothenate (vitamin B5) is phosphorylated to 4′-phosphopantothenate by the enzyme pantothenate kinase (PanK; CoaA; CoaX). This is the committed step in CoA biosynthesis and requires ATP. # A cysteine is added to 4′-phosphopantothenate by the enzyme phosphopantothenoylcysteine synthetase (PPCS; CoaB) to form 4'-phospho-N-pantothenoylcysteine (PPC).
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In enzymology, a formyl-CoA transferase () is an enzyme that catalyzes the chemical reaction :formyl-CoA + oxalate \rightleftharpoons formate + oxalyl- CoA Thus, the two substrates of this enzyme are formyl-CoA and oxalate, whereas its two products are formate and oxalyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is formyl-CoA:oxalate CoA-transferase. Other names in common use include formyl-coenzyme A transferase, and formyl-CoA oxalate CoA-transferase.
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Under typical physiological conditions, acetoacetic acid exists as its conjugate base, acetoacetate. Acetoacetate is produced in the mitochondria of the liver from acetoacetyl coenzyme A (CoA). First, another acetyl group is added from acetyl CoA to form 3-hydroxy-3-methylgluteryl CoA, then an acetyl CoA is lost from this, yielding acetoacetate. The initial acetoacetate can come from the last cycle in the beta oxidation of a fatty acid, or it can be synthesized from two acetyl CoA molecules, catalyzed by thiolase.
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In this section and in the next, the citric acid cycle intermediates are indicated in italics to distinguish them from other substrates and end-products. Pyruvate molecules produced by glycolysis are actively transported across the inner mitochondrial membrane, and into the matrix. Here they can be oxidized and combined with coenzyme A to form CO2, acetyl-CoA, and NADH, as in the normal cycle. However, it is also possible for pyruvate to be carboxylated by pyruvate carboxylase to form oxaloacetate.
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In enzymology, an oxalate CoA-transferase () is an enzyme that catalyzes the chemical reaction :succinyl-CoA + oxalate \rightleftharpoons succinate + oxalyl-CoA Thus, the two substrates of this enzyme are succinyl-CoA and oxalate, whereas its two products are succinate and oxalyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is succinyl-CoA:oxalate CoA-transferase. Other names in common use include succinyl-beta-ketoacyl-CoA transferase, and oxalate coenzyme A-transferase.
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On the other hand, it was shown that the presence of NADP+ at the structural site promotes the dimerization of dimers to form enzyme tetramers. It was also thought that the tetramer state was necessary for catalytic activity; however, this too was shown to be false. The NADP+ structural site is quite different from the NADP+ catalytic coenzyme binding site, and contains the nucleotide-binding fingerprint. The structural site bound to NADP+ possesses favorable interactions that keep it tightly bound.
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In the group that received three 100 mg capsules of coenzyme Q10 daily there were 43% fewer heart-related deaths compared with the placebo group. Also, there was a significant reduction in the need for hospitalization among patients in the Q10 group. The product used in the Q-Symbio study was Pharma Nord's 100 mg Q10 in soft-gel capsules (Myoqinon). The preparation is based on ubiquinone, the form of CoQ10 that has been used in scientific research for over 50 years.
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Reuterin is a potent antimicrobial compound produced by Lactobacillus reuteri. It is an intermediate in the metabolism of glycerol to 1,3-propanediol catalysed by the coenzyme B12-dependent diol dehydrase. Reuterin inhibits the growth of some harmful Gram-negative and Gram-positive bacteria, along with yeasts, molds, and protozoa. L. reuteri can secrete sufficient amounts of reuterin to inhibit the growth of harmful gut organisms, without killing beneficial gut bacteria, allowing L. reuteri to remove gut invaders while keeping normal gut flora intact.
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Acetaldehyde dehydrogenases () are dehydrogenase enzymes which catalyze the conversion of acetaldehyde into acetic acid. The oxidation of acetaldehyde to acetate can be summarized as follows: Acetaldehyde + NAD+ \+ Coenzyme A ↔ Acetyl-CoA + NADH + H+ In humans, there are three known genes which encode this enzymatic activity, ALDH1A1, ALDH2, and the more recently discovered ALDH1B1 (also known as ALDH5). These enzymes are members of the larger class of aldehyde dehydrogenases. The CAS number for this type of the enzyme is [9028-91-5].
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In L. sativus ODAP is synthesized in the young seedlings from the precursor (β-isoxazolin-5-on-2-yl)-alanine, also known as BIA. BIA has not been detected in mature plant parts or ripening seeds. The pathway begins with the formation of BIA from O-acetyl-L-serine (OAS) and isoxazolin-5-on. A ring opening leads to the formation of the short-lived intermediate 2,3-L-diaminopropanoic acid (DAPRO) which is then oxalylized by oxalyl-coenzyme A to form ODAP.
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Dichloroacetate may also be effective in treating Leigh syndrome-associated lactic acidosis; research is ongoing on this substance. Coenzyme Q10 supplements have been seen to improve symptoms in some cases. Clinical trials of the drug EPI-743 for Leigh syndrome are ongoing. In 2016, John Zhang and his team at New Hope Fertility Center in New York, USA, performed a spindle transfer mitochondrial donation technique on a mother in Mexico who was at risk of producing a baby with Leigh disease.
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Haem itself is not a photosensitiser, due to the coordination of a paramagnetic ion in the centre of the macrocycle, causing significant reduction in excited state lifetimes. The haem molecule is synthesised from glycine and succinyl coenzyme A (succinyl CoA). The rate-limiting step in the biosynthesis pathway is controlled by a tight (negative) feedback mechanism in which the concentration of haem regulates the production of ALA. However, this controlled feedback can be by-passed by artificially adding excess exogenous ALA to cells.
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These reactions are typically catalysed by enzymes with "histone acetyltransferase" (HAT) or "histone deacetylase" (HDAC) activity. Acetylation is the process where an acetyl functional group is transferred from one molecule (in this case, acetyl coenzyme A) to another. Deacetylation is simply the reverse reaction where an acetyl group is removed from a molecule. Acetylated histones, octameric proteins that organize chromatin into nucleosomes basic structural unit of the chromosomes and ultimately higher order structures, represent a type of epigenetic marker within chromatin.
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These organisms are typically found in anaerobic environments. In the earliest stage of H2/CO2 methanogenesis, CO2 binds to methanofuran (MF) and is reduced to formyl-MF. This endergonic reductive process (∆G˚’= +16 kJ/mol) is dependent on the availability of H2 and is catalyzed by the enzyme formyl-MF dehydrogenase. :CO2 + H2 + MF -> HCO-MF + H2O The formyl constituent of formyl-MF is then transferred to the coenzyme tetrahydromethanopterin (H4MPT) and is catalyzed by a soluble enzyme known as formyl transferase.
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Typically, initial signs and symptoms of this disorder occur during infancy and include low blood sugar (hypoglycemia), lack of energy (lethargy), and muscle weakness. There is also a high risk of complications such as liver abnormalities and life-threatening heart problems. Symptoms that begin later in childhood, adolescence, or adulthood tend to be milder and usually do not involve heart problems. Episodes of very long-chain acyl-coenzyme A dehydrogenase deficiency can be triggered by periods of fasting, illness, and exercise.
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The pathway produces two five-carbon building blocks called isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), which are used to make isoprenoids, a diverse class of over 30,000 biomolecules such as cholesterol, vitamin K, coenzyme Q10, and all steroid hormones. The mevalonate pathway begins with acetyl-CoA and ends with the production of IPP and DMAPP. It is best known as the target of statins, a class of cholesterol lowering drugs. Statins inhibit HMG-CoA reductase within the mevalonate pathway.
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Bacteria such as Escherichia coli and Bacillus stearothermophilus have versions of this enzyme and there appear to be two isoforms of SHMT in mammals, one in the cytoplasm (cSHMT) and another in the mitochondria (mSHMT). Plants may have an additional SHMT isoform within chloroplasts. In mammals, the enzyme is a tetramer of four identical subunits of approximately 50,000 Daltons each. The intact holoenzyme has a molecular weight of approximately 200,000 Daltons and incorporates four molecules of PLP as a coenzyme.
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Metabolic disorders in BTHS are exhibited in the form of 3-methylglutaconic aciduria (3-MGA), a condition characterized by increased levels of organic acids in urine, including 3‐methylglutaconic acid, 3‐methylglutaric acid, and 2‐ethyl- hydracrylic acid. While 3-MGA is largely excreted in BTHS patients, some patients have been found to have normal levels of organic acids in urine. Treatment of 3-MGA and metabolic deficiencies have included riboflavin or coenzyme Q10, which have shown significant improvement in patients.
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To complete the general phenylpropanoid pathway, 4-coumarate CoA ligase (4CL) substitutes coenzyme A (CoA) at the carboxy group of p-coumarate. Entering the flavone synthesis pathway, the type III polyketide synthase enzyme chalcone synthase (CHS) uses consecutive condensations of three equivalents of malonyl CoA followed by aromatization to convert p-coumaroyl-CoA to chalcone. Chalcone isomerase (CHI) then isomerizes the product to close the pyrone ring to make naringenin. Finally, a flavanone synthase (FNS) enzyme oxidizes naringenin to apigenin.
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Fatty acids from lipids are commonly used as an energy source by vertebrates as fatty acids are degraded through beta oxidation into acetate molecules. This acetate, bound to the active thiol group of coenzyme A, enters the citric acid cycle (TCA cycle) where it is fully oxidized to carbon dioxide. This pathway thus allows cells to obtain energy from fat. To utilize acetate from fat for biosynthesis of carbohydrates, the glyoxylate cycle, whose initial reactions are identical to the TCA cycle, is used.
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They are involved in hundreds of different biochemical pathways throughout biology, and are integral to some of life's most important processes. Transferases are involved in myriad reactions in the cell. Three examples of these reactions are the activity of coenzyme A (CoA) transferase, which transfers thiol esters, the action of N-acetyltransferase, which is part of the pathway that metabolizes tryptophan, and the regulation of pyruvate dehydrogenase (PDH), which converts pyruvate to acetyl CoA. Transferases are also utilized during translation.
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This is because fatty acids can only be metabolized in the mitochondria.Oxidation of fatty acids Red blood cells do not contain mitochondria and are therefore entirely dependent on anaerobic glycolysis for their energy requirements. In all other tissues, the fatty acids that enter the metabolizing cells are combined with coenzyme A to form acyl-CoA chains. These are transferred into the mitochondria of the cells, where they are broken down into acetyl-CoA units by a sequence of reactions known as β-oxidation.
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The systematic name of this enzyme class is linoleoyl-CoA,hydrogen- donor:oxygen oxidoreductase. Other names in common use include Delta6-desaturase (D6D or Δ-6-desaturase, termed 6 after omega-6 fatty acids), Delta6-fatty acyl-CoA desaturase, Delta6-acyl CoA desaturase, fatty acid Delta6-desaturase, fatty acid 6-desaturase, linoleate desaturase, linoleic desaturase, linoleic acid desaturase, linoleoyl CoA desaturase, linoleoyl- coenzyme A desaturase, and long-chain fatty acid Delta6-desaturase. This enzyme participates in linoleic acid metabolism. It employs one cofactor, iron.
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Several in vitro biochemical assays have been applied to monitor the catalytic activity of gamma-butyrobetaine dioxygenase. Early methods have mainly focused on the use of radiolabeled compounds, including 14C-labelled gamma-butyrobetaine and 14C-labelled 2OG. Enzyme-coupled method have also been applied to detect carnitine formation, by using the enzyme carnitine acetyltransferase and 14C-labelled acetyl-coenzyme A to give labelled acetylcarnitine for detection. Using this method, it is possible to detect carnitine concentration down to the pico-molar range.
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Although research is ongoing, treatment options are currently limited; vitamins are frequently prescribed, though the evidence for their effectiveness is limited. Pyruvate has been proposed in 2007 as a treatment option. N-acetyl cysteine reverses many models of mitochondrial dysfunction. In the case of mood disorders, specifically bipolar disorder, it is hypothesized that N-acetyl- cysteine (NAC), acetyl-L-carnitine (ALCAR), S-adenosylmethionine (SAMe), coenzyme Q10 (CoQ10), alpha-lipoic acid (ALA), creatine monohydrate (CM), and melatonin could be potential treatment options.
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In enzymology, a quinate O-hydroxycinnamoyltransferase () is an enzyme that catalyzes the chemical reaction :feruloyl-CoA + quinate \rightleftharpoons CoA + O-feruloylquinate Thus, the two substrates of this enzyme are feruloyl-CoA and quinate, whereas its two products are CoA and O-feruloylquinate. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is feruloyl-CoA:quinate O-(hydroxycinnamoyl)transferase. This enzyme is also called hydroxycinnamoyl coenzyme A-quinate transferase.
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An illustration of some common processes in the biogeochemical sulfur cycle. Sulfur is present in the environment in solids, gases, and aqueous species. Sulfur-containing solids on Earth include the common minerals pyrite (FeS2), galena (PbS), and gypsum (CaSO4•2H2O). Sulfur is also an important component of biological material, including in the essential amino acids cysteine and methionine, the B vitamins thiamine and biotin, and the ubiquitous substrate coenzyme A. In the ocean and other natural waters, sulfur is abundant as dissolved sulfate.
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Pantothenic acid, also called vitamin B5 is a water-soluble B vitamin and therefore an essential nutrient. All animals require pantothenic acid in order to synthesize coenzyme A (CoA) – essential for fatty acid metabolism – as well as to in general synthesize and metabolize proteins, carbohydrates, and fats. Pantothenic acid is the combination of pantoic acid and β-alanine. Its name derives from the Greek pantos, meaning "from everywhere", as minimally, at least small quantities of pantothenic acid are found in nearly every food.
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This carries only electrons, and these are transferred by the reduction and oxidation of an iron atom that the protein holds within a heme group in its structure. Cytochrome c is also found in some bacteria, where it is located within the periplasmic space. Within the inner mitochondrial membrane, the lipid-soluble electron carrier coenzyme Q10 (Q) carries both electrons and protons by a redox cycle. This small benzoquinone molecule is very hydrophobic, so it diffuses freely within the membrane.
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Enoyl-CoA-(∆) isomerase, also known as dodecenoyl-CoA-(∆) isomerase, 3,2-trans-enoyl-CoA isomerase, ∆3(cis),∆2(trans)-enoyl-CoA isomerase, or acetylene-allene isomerase, is an enzyme that catalyzes the conversion of cis- or trans-double bonds of coenzyme A (CoA) bound fatty acids at gamma-carbon (position 3) to trans double bonds at beta-carbon (position 2) as below: File:Enoyl-CoA isomerase reaction cis-trans.svg This enzyme has an important role in the metabolism of unsaturated fatty acids in beta oxidation.
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These two molecules are converted in the body to methylenecyclopropylacetic acid (MCPA), and are toxic with potential lethality. MCPA and hypoglycin A inhibit several enzymes involved in the breakdown of acyl CoA compounds, often binding irreversibly to coenzyme A, carnitine and carnitine acyltransferases I and II, reducing their bioavailability and consequently inhibiting beta oxidation of fatty acids. Glucose stores are consequently depleted leading to hypoglycemia and a condition called Jamaican vomiting sickness. These effects occur only when the unripe fruit is consumed.
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In enzymology, a beta-alanyl-CoA ammonia-lyase () is an enzyme that catalyzes the chemical reaction :beta-alanyl-CoA \rightleftharpoons acryloyl-CoA + NH3 Hence, this enzyme has one substrate, beta-alanyl-CoA, and two products, acryloyl-CoA and NH3. This enzyme belongs to the family of lyases, specifically ammonia lyases, which cleave carbon-nitrogen bonds. The systematic name of this enzyme class is beta-alanyl-CoA ammonia-lyase (acryloyl-CoA-forming). This enzyme is also called beta-alanyl coenzyme A ammonia-lyase.
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In 4-electron dehydrogenases, a single active site catalyses 2 separate oxidation steps: oxidation of the substrate alcohol to an intermediate aldehyde; and oxidation of the aldehyde to the product acid, in this case His. The reaction proceeds via a tightly- or covalently-bound inter-mediate, and requires the presence of 2 NAD molecules. By contrast with most dehydrogenases, the substrate is bound before the NAD coenzyme. A Cys residue has been implicated in the catalytic mechanism of the second oxidative step.
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It is carried out by methanogens, strictly anaerobic Archaea such as Methanococcus, Methanocaldococcus, Methanobacterium, Methanothermus, Methanosarcina, Methanosaeta and Methanopyrus. The biochemistry of methanogenesis is unique in nature in its use of a number of unusual cofactors to sequentially reduce methanogenic substrates to methane, such as coenzyme M and methanofuran. These cofactors are responsible (among other things) for the establishment of a proton gradient across the outer membrane thereby driving ATP synthesis. Several types of methanogenesis occur, differing in the starting compounds oxidized.
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The protein encoded by this gene is an isozyme of the long-chain fatty-acid- coenzyme A ligase family. Although differing in substrate specificity, subcellular localization, and tissue distribution, all isozymes of this family convert free long-chain fatty acids into fatty acyl-CoA esters, and thereby play a key role in lipid biosynthesis and fatty acid degradation. Several transcript variants encoding different isoforms have been found for this gene. This specific protein is most commonly found in mitochondria and peroxisomes.
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Acyl-coenzyme A thioesterase 8 is an enzyme that in humans is encoded by the ACOT8 gene. The protein encoded by this gene is a peroxisomal thioesterase that appears to be involved more in the oxidation of fatty acids rather than in their formation. The encoded protein can bind to the human immunodeficiency virus-1 protein Nef, and mediate Nef-induced down-regulation of CD4 in T-cells. Multiple transcript variants encoding several different isoforms have been found for this gene.
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Phenylacetyl-CoA (C29H42N7O17P3S) is a form of acetyl-CoA formed from the condensation of the thiol group from Coenzyme A with the carboxyl group of phenylacetic acid. Its molecular-weight is 885.7 g/mol. and IUPAC name is S-[2-[3-(2R)-4- [(2R,3S,4R,5R)-5-(6-aminopurin-9-yl)-4-hydroxy-3-phosphonooxyoxolan-2-yl]methoxy- hydroxyphosphoryl]oxy- hydroxyphosphoryl]oxy-2-hydroxy-3,3-dimethylbutanoyl]amino]propanoylamino]ethyl] 2-phenylethanethioate. It is formed via the actions of Phenylacetate—CoA ligase.
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Uracil's use in the body is to help carry out the synthesis of many enzymes necessary for cell function through bonding with riboses and phosphates. Uracil serves as allosteric regulator and coenzyme for reactions in animals and in plants. UMP controls the activity of carbamoyl phosphate synthetase and aspartate transcarbamoylase in plants, while UDP and UTP requlate CPSase II activity in animals. UDP- glucose regulates the conversion of glucose to galactose in the liver and other tissues in the process of carbohydrate metabolism.
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When the adenylyl cyclase enzyme complex is stimulated, it results in the formation of Cyclic Adenosine 3', 5'-Monophosphate (cAMP), from Adenosine 5' Triphosphate (ATP). cAMP acts as a secondary messenger, as it moves from the plasma membrane into the cell and relays the signal. cAMP binds to, and activates cAMP-dependent protein kinase A (PKA), which is located intracellularly in the neuron. The PKA consists of a holoenzyme - it is a compound which becomes active due to the combination of an enzyme with a coenzyme.
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In enzymology, a palmitoyl-CoA hydrolase () is an enzyme in the family of hydrolases that specifically acts on thioester bonds. It catalyzes the hydrolysis of long chain fatty acyl thioesters of acyl carrier protein or coenzyme A to form free fatty acid and the respective thiol. palmitoyl-SCoA + H_2O \rightleftarrows CoASH + palmitate Thus, the two substrates of this enzyme are palmitoyl-CoA and H2O, whereas its two products are CoA and palmitate. It has a strict specificity for thioesters with a chain link greater than C10.
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Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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In enzymology, an ornithine monooxygenase () is an enzyme that catalyzes the chemical reaction :L-ornithine + NAD(P)H + O2 \rightleftharpoons N(5)-hydroxy- L-ornithine + NAD(P)+ \+ H2O Thus, the three substrates of this enzyme are L-ornithine, NAD(P)H and O2, whereas its three products are N(5)-hydroxy-L- ornithine, NAD(P)+ and H2O. The coenzyme is FAD. This enzyme belongs to the family of oxidoreductases, specifically the monooxygenases. The systematic name of this enzyme class is L-ornithine N5 monooxygenase (flavin-dependent).
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In enzymology, a glutarate-CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + glutarate + CoA \rightleftharpoons ADP + phosphate + glutaryl-CoA The 3 substrates of this enzyme are ATP, glutarate, and CoA, whereas its 3 products are ADP, phosphate, and glutaryl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is glutarate:CoA ligase (ADP-forming). Other names in common use include glutaryl-CoA synthetase, and glutaryl coenzyme A synthetase.
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The sucC RNA motif is a conserved RNA structure discovered using bioinformatics. sucC RNAs are found in the genus Pseudomonas, and are consistently found in possible 5' untranslated regions of sucC genes. These genes encode Succinyl coenzyme A synthetase, and are hypothesised to be regulated by the sucC RNAs. sucC genes participate in the citric acid cycle, and another gene involved in the citric acid cycle, sucA, is also predicted to be regulated by a conserved RNA structure (see sucA RNA motif and sucA-II RNA motif).
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In enzymology, an oxalyl-CoA decarboxylase (OXC) () is an enzyme primarily produced by the gastrointestinal bacterium Oxalobacter formigenes that catalyzes the chemical reaction :oxalyl-CoA \rightleftharpoons formyl-CoA + CO2 OXC belongs to the family of lyases, specifically the carboxy-lyases (decarboxylases), which cleave carbon-carbon bonds. The systematic name of this enzyme class is oxalyl-CoA carboxy-lyase (formyl-CoA-forming). Other names in common use include oxalyl coenzyme A decarboxylase, and oxalyl-CoA carboxy-lyase. This enzyme participates in glyoxylate and dicarboxylate metabolism.
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The pyrophosphate, formed from the hydrolysis of the two high-energy bonds in ATP, is immediately hydrolyzed to two molecule of Pi by inorganic pyrophosphatase. This reaction is highly exergonic which drives the activation reaction forward and makes it more favorable. In the second step, the thiol group of a cytosolic coenzyme A attacks the acyl-adenylate, displacing AMP to form thioester fatty acyl-CoA. In the second reaction, acyl-CoA is transiently attached to the hydroxyl group of carnitine to form fatty acyl–carnitine.
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Long-chain-fatty-acid—CoA ligase 4 is an enzyme that in humans is encoded by the ACSL4 gene. The protein encoded by this gene is an isozyme of the long- chain fatty-acid-coenzyme A ligase family. Although differing in substrate specificity, subcellular localization, and tissue distribution, all isozymes of this family convert free long-chain fatty acids into fatty acyl-CoA esters, and thereby play a key role in lipid biosynthesis and fatty acid degradation. This isozyme preferentially utilizes arachidonate as substrate.
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In a White House ceremony held on January 17, 1969, U.S. President Lyndon Johnson awarded Barker with the National Medal of Science "[f]or his profound study of the chemical activities of microorganisms, including the unraveling of fatty acid metabolism and the discovery of the active coenzyme form of vitamin B12."The President's National Medal of Science: Recipient Details - H.A. Barker, National Science Foundation. Accessed July 20, 2009. When the department of biochemistry was established in 1959, he was named as a professor there.
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The level of methylmalonic acid is not elevated in folic acid deficiency. Direct measurement of blood cobalamin remains the gold standard because the test for elevated methylmalonic acid is not specific enough. Vitamin B is one necessary prosthetic group to the enzyme methylmalonyl-coenzyme A mutase. Vitamin B deficiency is but one among the conditions that can lead to dysfunction of this enzyme and a buildup of its substrate, methylmalonic acid, the elevated level of which can be detected in the urine and blood.
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For capping with 7-methylguanylate, the capping enzyme complex (CEC) binds to RNA polymerase II before transcription starts. As soon as the 5′ end of the new transcript emerges from RNA polymerase II, the CEC carries out the capping process (this kind of mechanism ensures capping, as with polyadenylation). The enzymes for capping can only bind to RNA polymerase II, ensuring specificity to only these transcripts, which are almost entirely mRNA. Capping with NAD+, NADH, or 3′-dephospho-coenzyme A is targeted by promoter sequence.
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A single commonly-used chemical method exists for synchronization of cells in G1. It involves Lovastatin, a reversible competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, an enzyme vital in the production of mevalonic acid. Mevalonic acid is a key intermediate in the mevalonate pathway responsible for synthesis of cholesterol. Addition of cholesterol to Lovastatin-treated cells does not undo the arrest affect, so Lovastatin appears to inhibit the formation of some early intermediate in the pathway that is essential for progression through early G1.
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The resulting adduct decarboxylates. The resulting 1,3-dipole reductively acetylates lipoamide-E2. In terms of details, biochemical and structural data for E1 revealed a mechanism of activation of TPP coenzyme by forming the conserved hydrogen bond with glutamate residue (Glu59 in human E1) and by imposing a V-conformation that brings the N4’ atom of the aminopyrimidine to intramolecular hydrogen bonding with the thiazolium C2 atom. This unique combination of contacts and conformations of TPP leads to formation of the reactive C2-carbanion, eventually.
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His ACAM presentation also suggested that low levels of coenzyQ10 may result in the development of heart disease. Sinatra has often been critical of what he sees as, an over-emphasis on cholesterol as an independent risk factor for heart disease and of what he considers the over-prescription of statin drugs.Stephen Sinatra’s Heart, Health & Nutrition, February 2008. Most statin drugs, which block an enzyme pathway necessary for the body to produce cholesterol, also block the enzyme pathway by which the body naturally produces coenzyme Q10.
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N-Acetylglutamate synthase is an enzyme that serves as a replenisher of N-acetylglutamic acid to supplement any N-acetylglutamic acid lost by the cell through mitosis or degradation. NAGS synthesizes N-acetylglutamic acid by catalyzing the addition of an acetyl group from acetyl-coenzyme A to glutamate. In prokaryotes with non-cyclic ornithine production, NAGS is the sole method of N-acetylglutamic acid synthesis and is inhibited by arginine. Acetylation of glutamate is thought to prevent glutamate from being used by proline biosynthesis.
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Choline acetyltransferase (commonly abbreviated as ChAT, but sometimes CAT) is a transferase enzyme responsible for the synthesis of the neurotransmitter acetylcholine. ChAT catalyzes the transfer of an acetyl group from the coenzyme acetyl-CoA to choline, yielding acetylcholine (ACh). ChAT is found in high concentration in cholinergic neurons, both in the central nervous system (CNS) and peripheral nervous system (PNS). As with most nerve terminal proteins, ChAT is produced in the body of the neuron and is transported to the nerve terminal, where its concentration is highest.
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The process is controlled by steroidogenic acute regulatory protein (StAR) which sits in the mitochondrial membrane and regulates the passage of cholesterol. This is the rate-limiting step of steroid biosynthesis. Once StAR has transported cholesterol into the mitochondria, the cholesterol molecule undergoes a string of oxidation- reduction reactions catalyzed by a series of enzymes from the family of cytochrome P450 enzymes. A coenzyme system called adrenodoxin reductase transfers electrons to the P450 enzyme which initiates the oxidation-reduction reactions that transform cholesterol into the steroid hormones.
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450px Pyruvate decarboxylation requires a few cofactors in addition to the enzymes that make up the complex. The first is thiamine pyrophosphate (TPP), which is used by pyruvate dehydrogenase to oxidize pyruvate and to form a hydroxyethyl- TPP intermediate. This intermediate is taken up by dihydrolipoyl transacetylase and reacted with a second lipoamide cofactor to generate an acetyl-dihydrolipoyl intermediate, releasing TPP in the process. This second intermediate can then be attacked by the nucleophilic sulfur attached to Coenzyme A, and the dihydrolipoamide is released.
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Succinate dehydrogenase (SDH) or succinate-coenzyme Q reductase (SQR) or respiratory Complex II is an enzyme complex, found in many bacterial cells and in the inner mitochondrial membrane of eukaryotes. It is the only enzyme that participates in both the citric acid cycle and the electron transport chain. Histochemical analysis showing high succinate dehydrogenase in muscle demonstrates high mitochondrial content and high oxidative potential. In step 6 of the citric acid cycle, SQR catalyzes the oxidation of succinate to fumarate with the reduction of ubiquinone to ubiquinol.
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Cofactors can be divided into two major groups: organic cofactors, such as flavin or heme; and inorganic cofactors, such as the metal ions Mg2+, Cu+, Mn2+ and iron-sulfur clusters. Organic cofactors are sometimes further divided into coenzymes and prosthetic groups. The term coenzyme refers specifically to enzymes and, as such, to the functional properties of a protein. On the other hand, "prosthetic group" emphasizes the nature of the binding of a cofactor to a protein (tight or covalent) and, thus, refers to a structural property.
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Different sources give slightly different definitions of coenzymes, cofactors, and prosthetic groups. Some consider tightly bound organic molecules as prosthetic groups and not as coenzymes, while others define all non-protein organic molecules needed for enzyme activity as coenzymes, and classify those that are tightly bound as coenzyme prosthetic groups. These terms are often used loosely. A 1980 letter in Trends in Biochemistry Sciences noted the confusion in the literature and the essentially arbitrary distinction made between prosthetic groups and coenzymes group and proposed the following scheme.
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Complex I activity of the electron transport chain is substantially elevated by decanoic acid treatment. It should however be noted that orally ingested medium chain fatty acids would be very rapidly degraded by first-pass metabolism by being taken up in the liver via the portal vein, and are quickly metabolized via coenzyme A intermediates through β-oxidation and the citric acid cycle to produce carbon dioxide, acetate and ketone bodies. Whether the ketones β-hydroxybutryate and acetone have direct antiseizure activity is unclear.
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The adenosyl version of B12 catalyzes rearrangements in which a hydrogen atom is directly transferred between two adjacent atoms with concomitant exchange of the second substituent, X, which may be a carbon atom with substituents, an oxygen atom of an alcohol, or an amine. Methylmalonyl coenzyme A mutase (MUT) converts MMl-CoA to Su-CoA, an important step in the extraction of energy from proteins and fats. Although far less common than other metalloproteins (e.g. those of zinc and iron), other cobaltoproteins are known besides B12.
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In contrast, the main function of NADPH is as a reducing agent in anabolism, with this coenzyme being involved in pathways such as fatty acid synthesis and photosynthesis. Since NADPH is needed to drive redox reactions as a strong reducing agent, the NADP/NADPH ratio is kept very low. Although it is important in catabolism, NADH is also used in anabolic reactions, such as gluconeogenesis. This need for NADH in anabolism poses a problem for prokaryotes growing on nutrients that release only a small amount of energy.
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Although some more ATP is generated in the citric acid cycle, the most important product is NADH, which is made from NAD+ as the acetyl-CoA is oxidized. This oxidation releases carbon dioxide as a waste product. In anaerobic conditions, glycolysis produces lactate, through the enzyme lactate dehydrogenase re- oxidizing NADH to NAD+ for re-use in glycolysis. An alternative route for glucose breakdown is the pentose phosphate pathway, which reduces the coenzyme NADPH and produces pentose sugars such as ribose, the sugar component of nucleic acids.
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Vitamin B12 functions as a coenzyme, meaning that its presence is required for enzyme-catalyzed reactions. Listed here are the three classes of enzymes that require B12 to function: # Isomerases #: Rearrangements in which a hydrogen atom is directly transferred between two adjacent atoms with concomitant exchange of the second substituent, X, which may be a carbon atom with substituents, an oxygen atom of an alcohol, or an amine. These use the adoB12 (adenosylcobalamin) form of the vitamin. # Methyltransferases #: Methyl (–CH3) group transfers between two molecules.
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Thus all of the DNA synthetic effects of B12 deficiency, including the megaloblastic anemia of pernicious anemia, resolve if sufficient dietary folate is present. Thus the best-known "function" of B12 (that which is involved with DNA synthesis, cell- division, and anemia) is actually a facultative function which is mediated by B12-conservation of an active form of folate which is needed for efficient DNA production. Other cobalamin-requiring methyltransferase enzymes are also known in bacteria, such as Me-H4-MPT, coenzyme M methyltransferase.
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In enzymology, a tartronate O-hydroxycinnamoyltransferase () is an enzyme that catalyzes the chemical reaction :sinapoyl-CoA + 2-hydroxymalonate \rightleftharpoons CoA + sinapoyltartronate Thus, the two substrates of this enzyme are sinapoyl-CoA and 2-hydroxymalonate, whereas its two products are CoA and sinapoyltartronate. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is sinapoyl- CoA:2-hydroxymalonate O-(hydroxycinnamoyl)transferase. Other names in common use include tartronate sinapoyltransferase, and hydroxycinnamoyl- coenzyme-A:tartronate hydroxycinnamoyltransferase.
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If mitochondrial dysfunction or mitochondrial diseases are the cause of mood disorders like bipolar disorder, then it has been hypothesized that N-acetyl-cysteine (NAC), acetyl-L-carnitine (ALCAR), S-adenosylmethionine (SAMe), coenzyme Q10 (CoQ10), alpha-lipoic acid (ALA), creatine monohydrate (CM), and melatonin could be potential treatment options. In determining treatment, there are many types of depression scales that are used. One of the depression scales is a self-report scale called Beck Depression Inventory (BDI). Another scale is the Hamilton Depression Rating Scale (HAMD).
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The classic clinical syndrome for vitamin B6 deficiency is a seborrhoeic dermatitis-like eruption, atrophic glossitis with ulceration, angular cheilitis, conjunctivitis, intertrigo, and neurologic symptoms of somnolence, confusion, and neuropathy (due to impaired sphingosine synthesis) and sideroblastic anemia (due to impaired heme synthesis). Less severe cases present with metabolic disease associated with insufficient activity of the coenzyme PLP. The most prominent of the lesions is due to impaired tryptophan–niacin conversion. This can be detected based on urinary excretion of xanthurenic acid after an oral tryptophan load.
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Agents currently under investigation include, antiglutamatergics, monoamine oxidase inhibitors (selegiline, rasagiline), promitochondrials (coenzyme Q10, creatine), calcium channel blockers (isradipine) and growth factors (GDNF). Reducing alpha- synuclein pathology is a major focus of preclinical research. A vaccine that primes the human immune system to destroy alpha-synuclein, PD01A (developed by Austrian company, Affiris), entered clinical trials and a phase 1 report in 2020 suggested safety and tolerability. In 2018, an antibody, PRX002/RG7935, showed preliminary safety evidence in stage I trials supporting continuation to stage II trials.
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A cytochrome is a kind of electron-transferring protein that contains at least one heme group. The iron atoms inside complex III's heme groups alternate between a reduced ferrous (+2) and oxidized ferric (+3) state as the electrons are transferred through the protein. The reaction catalyzed by complex III is the oxidation of one molecule of ubiquinol and the reduction of two molecules of cytochrome c, a heme protein loosely associated with the mitochondrion. Unlike coenzyme Q, which carries two electrons, cytochrome c carries only one electron.
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Methanocaldococcus jannaschii is a thermophilic methanogen, meaning it grows by making methane as a metabolic byproduct. It is only capable of growth on carbon dioxide and hydrogen as primary energy sources, unlike many other methanococci (such as Methanococcus maripalidus) which can also use formate as a primary energy source. The genome includes many hydrogenases, such as a 5,10-methenyltetrahydromethanopterin hydrogenase, a ferredoxin hydrogenase (eha), and a coenzyme F420 hydrogenase. Proteomic studies showed that M. jannaschii contains a large number of inteins: 19 were discovered by one study.
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In addition, some fluorescent Pseudomonads lack apparent homologs of these genes, further calling into question whether this is the function of these genes. This is consistent with reports that pvdL combines coenzyme A to a myristic acid moiety, then adds a glutamate, D-tyrosine, and L-2,4-diaminobutyric acid (DAB). An alternate biosynthetic pathway suggests that pvdL incorporates glutamate, 2,4,5-trihydroxyphenylalanine and L-2,4-daminobutyric acid instead. This latter is supported by the identification of incorporation of a radiolabeled tyrosine into either pyoverdine or pseudoverdine.
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Some examples of inorganic cofactors are iron or magnesium, and some examples of organic cofactors include ATP or coenzyme A. Organic cofactors are more specifically known as coenzymes, and many enzymes require the addition of coenzymes to assume normal catalytic function in a metabolic reaction. The coenzymes bind to the active site of an enzyme to promote catalysis. By engineering cofactors and coenzymes, a naturally occurring metabolic reaction can be manipulated to optimize the output of a metabolic network. Common cofactor NADH, the first discovered.
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Pantothenate kinase 2, mitochondrial is an enzyme that in humans is encoded by the PANK2 gene. This gene encodes a protein belonging to the pantothenate kinase family and is the only member of that family to be expressed in mitochondria. Pantothenate kinase is a key regulatory enzyme in the biosynthesis of coenzyme A (CoA) in bacteria and mammalian cells. It catalyzes the first committed step in the universal biosynthetic pathway leading to CoA and is itself subject to regulation through feedback inhibition by acyl CoA species.
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S-Adenosylethionine can bind as a substrate for ACC synthase (with higher affinity than SAM) and therefore inhibit any reaction with SAM. ACC Synthase is also competitively inhibited by aminoethoxyvinylglycine (AVG) and aminooxyacetic acid (AOA), inhibitors to many pyridoxal phosphate-mediated enzymic reactions. They are natural toxins that cause slow binding inhibition by interfering with the coenzyme pyridoxal phosphate. ACC synthase activity is also inhibited by intermediates of the activated methyl cycle and the methionine-recycling pathway: 5′-methylthioadenosine, α-keto-γ-methylthiobutyric acid, and S-adenosylhomocysteine.
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ACSS3 is part of a family known as Acyl-coenzyme A synthetases (ACSs), which catalyze the initial reaction in fatty acid metabolism. This reaction activates fatty acids via thioesterification to CoA, thereby allowing their participation in both anabolic and catabolic pathways. The existence of many ACSs suggests that each plays a unique role, directing the acyl-CoA product to a specific metabolic fate. Knowing the full complement of ACS genes in the human genome will facilitate future studies to characterize their specific biological functions.
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Brown's research interests focused on metabolic biochemistry, particularly in prokaryotes. His PhD work involved isolating and identifying a compound needed for the growth of Lactobacillus bulgaricus, which proved to be pantethine, an intermediate in the synthesis of coenzyme A. He based his research as a faculty member on broadening this work to identifying additional coenzymes and studying their biosynthesis. He was particularly instrumental in understanding the biosynthesis of folic acid and related pteridine compounds, and later described this work as the research he was most proud of.
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These recycling reactions are catalyzed by an alcohol dehydrogenase (NAD+), and a phosphotransacetylase (coenzyme A), resulting in a phosphorylated acyl compound that can readily be a source of substrate-level phosphorylation or enter central metabolism, depending on if the organism is growing aerobically or anaerobically. It seems that most, if not all, metabolosomes utilize these core enzymes. Metabolosomes also encapsulate another enzyme that is specific to the initial substrate of the BMC, that generates the aldehyde; this is considered the signature enzyme of the BMC.
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Polyprenyl synthetases are a class of enzymes responsible for synthesis of isoprenoids. Isoprenoid compounds are synthesized by various organisms. For example, in eukaryotes the isoprenoid biosynthetic pathway is responsible for the synthesis of a variety of end products including cholesterol, dolichol, ubiquinone or coenzyme Q. In bacteria this pathway leads to the synthesis of isopentenyl tRNA, isoprenoid quinones, and sugar carrier lipids. Among the enzymes that participate in that pathway, are a number of polyprenyl synthetase enzymes which catalyze a 1'4-condensation between 5-carbon isoprene units.
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The cells range in shape from egg-shaped, ellipsoidal, to elongated, measuring 2.5–5.0 by 5.0–15.0 µm, and occurring singly, doubly, or in groups of four. Asymmetrical blastoconidia are borne on short sterigmata, and measure 2.0–5.0 by 3.0–7.0 µm. The optimal growth temperature for the fungus occurs at a range of ; growth stops at . Like other Sporobolomyces species, S. koalae has coenzyme Q10 as its major ubiquinone, it lacks the monosaccharide xylose in whole-cell hydrolysates, and it cannot ferment sugars.
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In biochemistry, flavin adenine dinucleotide (FAD) is a redox-active coenzyme associated with various proteins, which is involved with several enzymatic reactions in metabolism. A flavoprotein is a protein that contains a flavin group, which may be in the form of FAD or flavin mononucleotide (FMN). Many flavoproteins are known: components of the succinate dehydrogenase complex, α-ketoglutarate dehydrogenase, and a component of the pyruvate dehydrogenase complex. FAD can exist in four redox states, which are the flavin-N(5)-oxide, quinone, semiquinone, and hydroquinone.
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In enzymology, a long-chain-enoyl-CoA hydratase () is an enzyme that catalyzes the chemical reaction :(3S)-3-hydroxyacyl-CoA \rightleftharpoons trans-2-enoyl-CoA + H2O Hence, this enzyme has one substrate, (3S)-3-hydroxyacyl-CoA, and two products, trans-2-enoyl-CoA and H2O. This enzyme belongs to the family of lyases, specifically the hydro-lyases, which cleave carbon-oxygen bonds. The systematic name of this enzyme class is long- chain-(3S)-3-hydroxyacyl-CoA hydro-lyase. This enzyme is also called long- chain enoyl coenzyme A hydratase.
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Interest has grown in lanosterol synthase inhibitors as drugs to lower blood cholesterol and treat atherosclerosis. The widely popular statin drugs currently used to lower LDL (low-density lipoprotein) cholesterol function by inhibiting HMG-CoA reductase activity. Because this enzyme catalyzes the formation of precursors far upstream of (S)-2,3-epoxysqualene and cholesterol, statins may negatively influence amounts of intermediates required for other biosynthetic pathways (e.g. synthesis of isoprenoids, coenzyme Q). Thus, lanosterol synthase, which is more closely tied to cholesterol biosynthesis than HMG-CoA reductase, is an attractive drug target.
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This vitamin is important for the facilitation of glucose use, thus ensuring the production of energy for the brain, and normal functioning of the nervous system, muscles and heart. Thiamine is found throughout mammalian nervous tissue, including the brain and spinal cord. Metabolism and coenzyme function of the vitamin suggest a distinctive function for thiamine within the nervous system. The brain retains its thiamine content in the face of a vitamin-deficient diet with great tenacity, as it is the last of all nervous tissues studied to become depleted.
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An oxidoreductase using NADH as a substrate could therefore be assayed by following the decrease in UV absorbance at a wavelength of 340 nm as it consumes the coenzyme. Direct versus coupled assays Coupled assay for hexokinase using glucose-6-phosphate dehydrogenase. Even when the enzyme reaction does not result in a change in the absorbance of light, it can still be possible to use a spectrophotometric assay for the enzyme by using a coupled assay. Here, the product of one reaction is used as the substrate of another, easily detectable reaction.
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The human NDUFB1 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. However, NDUFB1 is an accessory subunit of the complex that is believed not to be involved in catalysis. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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The human NDUFB2 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. However, NDUFB2 is an accessory subunit of the complex that is believed not to be involved in catalysis. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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The human NDUFB3 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. However, NDUFB3 is an accessory subunit of the complex that is believed not to be involved in catalysis. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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Here, acetyl-CoA is generated for oxidation and energy production. In the citric acid cycle, coenzyme A works as an allosteric regulator in the stimulation of the enzyme pyruvate dehydrogenase. New research has found that protein CoAlation plays an important role in regulation of the oxidative stress response. Protein CoAlation plays a similar role to S-glutathionylation in the cell, and prevents the irreversible oxidation of the thiol group in cysteine on the surface of cellular proteins, while also directly regulating enzymatic activity in response to oxidative or metabolic stress.
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In enzymology, a 5-hydroxypentanoate CoA-transferase () is an enzyme that catalyzes the chemical reaction :acetyl-CoA + 5-hydroxypentanoate \rightleftharpoons acetate + 5-hydroxypentanoyl-CoA Thus, the two substrates of this enzyme are acetyl-CoA and 5-hydroxypentanoate, whereas its two products are acetate and 5-hydroxypentanoyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is acetyl-CoA:5-hydroxypentanoate CoA-transferase. Other names in common use include 5-hydroxyvalerate CoA-transferase, and 5-hydroxyvalerate coenzyme A transferase.
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In enzymology, a 3-oxoadipate CoA-transferase () is an enzyme that catalyzes the chemical reaction :succinyl-CoA + 3-oxoadipate \rightleftharpoons succinate + 3-oxoadipyl-CoA Thus, the two substrates of this enzyme are succinyl-CoA and 3-oxoadipate, whereas its two products are succinate and 3-oxoadipyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA-transferases. The systematic name of this enzyme class is succinyl-CoA:3-oxoadipate CoA-transferase. Other names in common use include 3-oxoadipate coenzyme A-transferase, and 3-oxoadipate succinyl-CoA transferase.
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The mechanisms of enzyme-catalyzed reactions can also be studied using crossover experiments. Examples of the application of this technique in biochemistry include the study of reactions catalyzed by nucleoside diphosphohexose-4,6-dehydratases, the aconitase-catalyzed elimination of water from citrate, and various reactions catalyzed by coenzyme B12-dependent enzymes, among others. Unlike isotope labeling studies in organic and organometallic chemistry, which typically use deuterium when an isotope of hydrogen is desired, biochemical crossover experiments frequently employ tritium.Silverman, Richard B.; The Organic Chemistry of Enzyme- Catalyzed Reactions; Academic Press, London, 2002.
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In enzymology, a biotin-CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + biotin + CoA \rightleftharpoons AMP + diphosphate + biotinyl- CoA The 3 substrates of this enzyme are ATP, biotin, and CoA, whereas its 3 products are AMP, diphosphate, and biotinyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid- thiol ligases. The systematic name of this enzyme class is biotin:CoA ligase (AMP-forming). Other names in common use include biotinyl-CoA synthetase, biotin CoA synthetase, and biotinyl coenzyme A synthetase.
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In enzymology, a 2-furoate—CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + 2-furoate + CoA \rightleftharpoons AMP + diphosphate + 2-furoyl-CoA The 3 substrates of this enzyme are ATP, 2-furoate, and CoA, whereas its 3 products are AMP, diphosphate, and 2-furoyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is 2-furoate:CoA ligase (AMP-forming). This enzyme is also called 2-furoyl coenzyme A synthetase.
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In enzymology, an acid-CoA ligase (GDP-forming) () is an enzyme that catalyzes the chemical reaction :GTP + an acid + CoA \rightleftharpoons GDP + phosphate + acyl-CoA The 3 substrates of this enzyme are GTP, acid, and CoA, whereas its 3 products are GDP, phosphate, and acyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is acid:CoA ligase (GDP- forming). Other names in common use include acyl-CoA synthetase (GDP-forming), and acyl coenzyme A synthetase (guanosine diphosphate forming).
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In enzymology, a phosphopantothenate-cysteine ligase also known as phosphopantothenoylcysteine synthetase (PPCS) is an enzyme that catalyzes the chemical reaction which constitutes the second of five steps involved in the conversion of pantothenate to Coenzyme A. The reaction is: :NTP + (R)-4'-phosphopantothenate + L-cysteine \rightleftharpoons NMP + diphosphate + N-[(R)-4'-phosphopantothenoyl]-L-cysteine The nucleoside triphosphate (NTP) involved in the reaction varies from species to species. Phosphopantothenate—cysteine ligase from the bacterium Escherichia coli uses cytidine triphosphate (CTP) as an energy donor, whilst the human isoform uses adenosine triphosphate (ATP).
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In enzymology, a malate-CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + malate + CoA \rightleftharpoons ADP + phosphate + malyl-CoA The 3 substrates of this enzyme are ATP, malate, and CoA, whereas its 3 products are ADP, phosphate, and malyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is malate:CoA ligase (ADP- forming). Other names in common use include malyl-CoA synthetase, malyl coenzyme A synthetase, and malate thiokinase.
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In enzymology, a citramalyl-CoA lyase () is an enzyme that catalyzes the chemical reaction :(3S)-citramalyl-CoA \rightleftharpoons acetyl-CoA + pyruvate Hence, this enzyme has one substrate, (3S)-citramalyl-CoA, and two products, acetyl-CoA and pyruvate. This enzyme belongs to the family of lyases, specifically the oxo-acid-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is (3S)-citramalyl-CoA pyruvate-lyase (acetyl-CoA-forming). Other names in common use include citramalyl coenzyme A lyase, (+)-CMA-CoA lyase, and (3S)-citramalyl-CoA pyruvate-lyase.
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In enzymology, a propionate CoA-transferase () is an enzyme that catalyzes the chemical reaction :acetyl-CoA + propanoate \rightleftharpoons acetate + propanoyl-CoA Thus, the two substrates of this enzyme are acetyl-CoA and propanoate, whereas its two products are acetate and propanoyl-CoA. This enzyme belongs to the family of transferases, specifically the CoA- transferases. The systematic name of this enzyme class is acetyl- CoA:propanoate CoA-transferase. Other names in common use include propionate coenzyme A-transferase, propionate-CoA:lactoyl-CoA transferase, propionyl CoA:acetate CoA transferase, and propionyl-CoA transferase.
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TMABA is then dehydrogenated into gamma-butyrobetaine in an NAD+-dependent reaction, catalyzed by TMABA dehydrogenase. Gamma-butyrobetaine is then hydroxylated by gamma butyrobetaine hydroxylase (a zinc binding enzyme) into -carnitine, requiring iron in the form of Fe2+. Carnitine is involved in transporting fatty acids across the mitochondrial membrane, by forming a long chain acetylcarnitine ester and being transported by carnitine palmitoyltransferase I and carnitine palmitoyltransferase II. Carnitine also plays a role in stabilizing Acetyl-CoA and coenzyme A levels through the ability to receive or give an acetyl group.
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The conjugate base of oxalic acid is the hydrogenoxalate anion, and its conjugate base (oxalate) is a competitive inhibitor of the lactate dehydrogenase (LDH) enzyme. LDH catalyses the conversion of pyruvate to lactic acid (end product of the fermentation (anaerobic) process) oxidising the coenzyme NADH to NAD+ and H+ concurrently. Restoring NAD+ levels is essential to the continuation of anaerobic energy metabolism through glycolysis. As cancer cells preferentially use anaerobic metabolism (see Warburg effect) inhibition of LDH has been shown to inhibit tumor formation and growth, thus is an interesting potential course of cancer treatment.
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In 1961 he became a Fellow of the Royal Society and in 1963 as Fellow of the Royal Society of Edinburgh. He was awarded the Davy Medal in 1974 with the citation: In recognition of his distinguished researches on coenzyme A and studies of the constituents of bacterial cell walls. He was knighted in 1977.Obituary in The Independent 3 January 2009, accessed 10 January 2011 Other awards were DSc (Manchester), ScD (Cantab), and Honorary DSc's from Heriot-Watt University(1979) and also the University of Bath (1986).
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Acyl-CoA thioesterase 2, also known as ACOT2, is an enzyme which in humans is encoded by the ACOT2 gene. Acyl-CoA thioesterases, such as ACOT2, are a group of enzymes that hydrolyze Coenzyme A (CoA) esters, such as acyl-CoAs, bile CoAs, and CoA esters of prostaglandins, to the corresponding free acid and CoA. ACOT2 shows high acyl-CoA thioesterase activity on medium- and long-chain acyl-CoAs, with an optimal pH of 8.5. It is most active on myristoyl-CoA but also shows high activity on palmitoyl-CoA, stearoyl-CoA, and arachidoyl-CoA.
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The human NDUFA1 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. However, NDUFA1 is an accessory subunit of the complex that is believed not to be involved in catalysis. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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Methanogen homoaconitase (, methanogen HACN) is an enzyme with systematic name (R)-2-hydroxybutane-1,2,4-tricarboxylate hydro-lyase ((1R,2S)-1-hydroxybutane-1,2,4-tricarboxylate-forming). This enzyme catalyses the following chemical reaction : (R)-2-hydroxybutane-1,2,4-tricarboxylate \rightleftharpoons (1R,2S)-1-hydroxybutane-1,2,4-tricarboxylate (overall reaction) : (1a) (R)-2-hydroxybutane-1,2,4-tricarboxylate \rightleftharpoons (Z)-but-1-ene-1,2,4-tricarboxylate + H2O : (1b) (Z)-but-1-ene-1,2,4-tricarboxylate + H2O \rightleftharpoons (1R,2S)-1-hydroxybutane-1,2,4-tricarboxylate This enzyme catalyses several reactions in the pathway of coenzyme-B biosynthesis in methanogenic archaea.
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Synergistic catalysts are very common in biological systems. The reactions occur by a molecule binding to a protein as a substrate and becoming active and being reacted with a coenzyme such as NADPH which is essentially an activated hydride. A specific example of this is shown by the synthesis of tetrahydrofolate via the enzyme dihydrofolate reductase. Dihydrofolate reductase catalytically activates dihydrofolate by protonating the imine, while NADPH, essentially a hydride source activated by the cofactor NADP+, can then come in and add a hydride across the imine to afford the product.
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ACADVL is linked with very long-chain acyl-coenzyme A dehydrogenase deficiency (VLCADD), which has many symptoms, and typically presents as one of three phenotypes. The first is severe, with an early childhood onset and high mortality rate; the most common symptom is this form is cardiomyopathy. The second is a late onset childhood form, with milder symptoms that present most commonly as hypoketotic hypoglycemia. The final form presents in adulthood, and presents as isolated skeletal muscle involvement, rhabdomyolysis, and myoglobinuria, which is triggered by exercise or fasting.
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In recent years, the cosmetic industry is mainly focused towards products made with natural ingredients and it is oriented to a sustainable consumption. Because of their natural origin, milk components correspond in many fields to the needs of cosmetology. Recent scientific study on a cream containing of lyophilized donkey milk showed different benefits for the skin. These results are related to the effectiveness of donkey milk components like proteins, minerals, vitamins, essential fatty acids, bioactive enzyme and coenzyme which allow the skin a balanced nourishment and a proper hydration.
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MCPA forms non-metabolizable esters with coenzyme A (CoA) and carnitine, causing a decrease in their bioavailability and concentration in bodily tissue. Both of these cofactors are necessary for the β-oxidation of fatty acids, which in turn is vital for gluconeogenesis. MCPA also inhibits the dehydrogenation of a number of Acyl-CoA dehydrogenases. The inhibition of one in particular, butyryl CoA dehydrogenase (a short-chain acyl-CoA dehydrogenase), causes β-oxidation to cease before fully realized, which leads to a decrease in the production of NADH and Acetyl-CoA.
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A rarer form of hyperphenylalaninemia is tetrahydrobiopterin deficiency, which occurs when the PAH enzyme is normal, and a defect is found in the biosynthesis or recycling of the cofactor tetrahydrobiopterin (BH4). BH4 is necessary for proper activity of the enzyme PAH, and this coenzyme can be supplemented as treatment. Those who suffer from this form of hyperphenylalaninemia may have a deficiency of tyrosine (which is created from phenylalanine by PAH), in which case treatment is supplementation of tyrosine to account for this deficiency. Levels of dopamine can be used to distinguish between these two types.
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The risk of statin-induced rhabdomyolysis increases with older age, use of interacting medications such as fibrates, and hypothyroidism. Coenzyme Q10 (ubiquinone) levels are decreased in statin use; CoQ10 supplements are sometimes used to treat statin- associated myopathy, though evidence of their efficacy is lacking . The gene SLCO1B1 (Solute carrier organic anion transporter family member 1B1) codes for an organic anion-transporting polypeptide that is involved in the regulation of the absorption of statins. A common variation in this gene was found in 2008 to significantly increase the risk of myopathy.
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In overall terms, the reaction catalyzed by serine dehydratase involves two steps: catalytic elimination and a nonenzymatic hydrolysis reaction. The main role of SDH is to lower the activation energy of this reaction by binding the coenzyme and substrate in a particular conformational geometry. Mechanistic Steps: (In panel 1 of Figure 5) In the SDH enzyme's active site, Lys41 is located above the PLP molecule with its R group NH2 connected to C4 of PLP by a Schiff base linkage. The phosphate group of PLP is located in a pocket of G residues.
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This NAD is carried into the mitochondrion by a specific membrane transport protein, since the coenzyme cannot diffuse across membranes. The balance between the oxidized and reduced forms of nicotinamide adenine dinucleotide is called the NAD/NADH ratio. This ratio is an important component of what is called the redox state of a cell, a measurement that reflects both the metabolic activities and the health of cells. The effects of the NAD/NADH ratio are complex, controlling the activity of several key enzymes, including glyceraldehyde 3-phosphate dehydrogenase and pyruvate dehydrogenase.
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In 1936, the German scientist Otto Heinrich Warburg showed the function of the nucleotide coenzyme in hydride transfer and identified the nicotinamide portion as the site of redox reactions. Vitamin precursors of NAD were first identified in 1938, when Conrad Elvehjem showed that liver has an "anti-black tongue" activity in the form of nicotinamide. Then, in 1939, he provided the first strong evidence that niacin is used to synthesize NAD. In the early 1940s, Arthur Kornberg was the first to detect an enzyme in the biosynthetic pathway.
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The human NDUFB5 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. However, NDUFB5 is an accessory subunit of the complex that is believed not to be involved in catalysis. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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The human NDUFAB1 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. However, NDUFAB1 is an accessory subunit of the complex that is believed not to be involved in catalysis. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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In enzymology, a 2-acylglycerol O-acyltransferase () is an enzyme that catalyzes the chemical reaction :acyl-CoA + 2-acylglycerol \rightleftharpoons CoA + diacylglycerol Thus, the two substrates of this enzyme are acyl-CoA and 2-acylglycerol, whereas its two products are CoA and diacylglycerol. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acyl-CoA:2-acylglycerol O-acyltransferase. Other names in common use include acylglycerol palmitoyltransferase, monoglyceride acyltransferase, acyl coenzyme A-monoglyceride acyltransferase, and monoacylglycerol acyltransferase.
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In enzymology, a 10-hydroxytaxane O-acetyltransferase () is an enzyme that catalyzes the chemical reaction :acetyl-CoA + 10-desacetyltaxuyunnanin C \rightleftharpoons CoA + taxuyunnanin C Thus, the two substrates of this enzyme are acetyl-CoA and 10-desacetyltaxuyunnanin C, whereas its two products are CoA and taxuyunnanin C. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acetyl-CoA:taxan-10beta-ol O-acetyltransferase. This enzyme is also called acetyl coenzyme A: 10-hydroxytaxane O-acetyltransferase.
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Biosynthesis of the 17C monic acid unit begins on MmpD (Figure 1). One of the AT domains from MmpC may transfer an activated acetyl group from acetyl- Coenzyme A (CoA) to the first ACP domain. The chain is extended by malonyl- CoA, followed by a SAM-dependent methylation at C12 (see Figure 2 for PA-A numbering) and reduction of the B-keto group to an alcohol. The dehydration (DH) domain in module 1 is predicted to be non-functional due to a mutation in the conserved active site region.
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Anaerobic micro-organisms like Acetogens undergo the Wood-Ljungdahl Pathway, relying on CODH to produce CO by reduction of CO2 needed for the synthesis of Acetyl-CoA from a methyl, coenzyme a (CoA) and corrinoid iron-sulfur protein. Other types show CODH being utilized to generate a proton motive force for the purposes of energy generation. CODH is used for the CO oxidation, producing two protons which are subsequently reduced to form dihydrogen (H2, known colloquially as molecular hydrogen), providing the necessary free energy to drive ATP generation.
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Succinate-Q oxidoreductase. Succinate-Q oxidoreductase, also known as complex II or succinate dehydrogenase, is a second entry point to the electron transport chain. It is unusual because it is the only enzyme that is part of both the citric acid cycle and the electron transport chain. Complex II consists of four protein subunits and contains a bound flavin adenine dinucleotide (FAD) cofactor, iron–sulfur clusters, and a heme group that does not participate in electron transfer to coenzyme Q, but is believed to be important in decreasing production of reactive oxygen species.
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As coenzyme Q is reduced to ubiquinol on the inner side of the membrane and oxidized to ubiquinone on the other, a net transfer of protons across the membrane occurs, adding to the proton gradient. The rather complex two-step mechanism by which this occurs is important, as it increases the efficiency of proton transfer. If, instead of the Q cycle, one molecule of QH2 were used to directly reduce two molecules of cytochrome c, the efficiency would be halved, with only one proton transferred per cytochrome c reduced.
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In enzymology, a 3-hydroxybutyryl-CoA epimerase () is an enzyme that catalyzes the chemical reaction :(S)-3-hydroxybutanoyl-CoA \rightleftharpoons (R)-3-hydroxybutanoyl-CoA Hence, this enzyme has one substrate, (S)-3-hydroxybutanoyl-CoA, and one product, (R)-3-hydroxybutanoyl-CoA. This enzyme belongs to the family of isomerases, specifically those racemases and epimerases acting on hydroxy acids and derivatives. The systematic name of this enzyme class is 3-hydroxybutanoyl-CoA 3-epimerase. Other names in common use include 3-hydroxybutyryl coenzyme A epimerase, and 3-hydroxyacyl-CoA epimerase.
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Dixon published a series of papers on D-amino acid oxidase, detailing the kinetics and thermodynamics of association of the coenzyme with the apoprotein, the substrate and inhibitor specificity, and the effect of pH on the kinetic constants. Dixon was an expert on the theory and use of manometers. In 1931, he collaborated with David Keilin and Robin Hill to determine the first absorption spectrum of a cytochrome, cytochrome c. Dixon studied the chemistry of lachrymators and mustard gas and proposed a phosphokinase theory to explain their mode of action.
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Mutations in the HADH gene lead to inadequate levels of an enzyme called 3-hydroxyacyl-coenzyme A dehydrogenase. Medium-chain and short-chain fatty acids cannot be metabolized and processed properly without sufficient levels of this enzyme. As a result, these fatty acids are not converted to energy, which can lead to characteristic features of this disorder, such as lethargy and hypoglycemia. Medium-chain and short-chain fatty acids or partially metabolized fatty acids may build up in tissues and damage the liver, heart, and muscles, causing more serious complications.
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TMG is an important cofactor in methylation, a process that occurs in every mammalian cell donating methyl groups (–CH3) for other processes in the body. These processes include the synthesis of neurotransmitters such as dopamine and serotonin. Methylation is also required for the biosynthesis of melatonin and the electron transport chain constituent coenzyme Q10, as well as the methylation of DNA for epigenetics. The major step in the methylation cycle is the remethylation of homocysteine, a compound which is naturally generated during demethylation of the essential amino acid methionine.
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In enzymology, a pantetheine-phosphate adenylyltransferase () is an enzyme that catalyzes the chemical reaction :ATP + 4'-Phosphopantetheine\rightleftharpoons diphosphate + 3'-dephospho-CoA Thus, the two substrates of this enzyme are ATP and 4'-Phosphopantetheine, whereas its two products are diphosphate and 3'-dephospho-CoA. This enzyme belongs to the family of transferases, specifically those transferring phosphorus- containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is ATP:pantetheine-4'-phosphate adenylyltransferase. Other names in common use include dephospho-CoA pyrophosphorylase, pantetheine phosphate adenylyltransferase, dephospho-coenzyme A pyrophosphorylase, and 3'-dephospho-CoA pyrophosphorylase.
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The protein encoded by this gene is an isozyme of the long-chain fatty-acid-coenzyme A ligase family. Although differing in substrate specificity, subcellular localization, and tissue distribution, all isozymes of this family convert free long-chain fatty acids into fatty acyl- CoA esters, and thereby play a key role in lipid biosynthesis and fatty acid degradation. This isozyme is highly expressed in brain, and preferentially utilizes myristate, arachidonate, and eicosapentaenoate as substrates. The amino acid sequence of this isozyme is 92% identical to that of rat homolog.
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The pyruvate dehydrogenase (PDH) complex is located in the mitochondrial matrix and catalyzes the conversion of pyruvate to acetyl coenzyme A. The PDH complex thereby links glycolysis to the citric acid cycle. The PDH complex contains three catalytic subunits, E1, E2, and E3, two regulatory subunits, E1 kinase and E1 phosphatase, and a non-catalytic subunit, E3 binding protein (E3BP). This gene encodes the E3 binding protein subunit; also known as component X of the pyruvate dehydrogenase complex. This protein tethers E3 dimers to the E2 core of the PDH complex.
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Class I reductases are divided into IA and IB due to differences in regulation. Class IA reductases are distributed in eukaryotes, eubacteria, bacteriophages, and viruses. Class IB reductases are found in eubacteria. Class IB reductases can also use a radical generated with the stabilization of a binuclear manganese center. Class II reductases generate the free radical 5’-deoxyadenosyl radical from cobalamin (coenzyme B12) and have a simpler structure than class I and class III reductases. Reduction of NDPs or ribonucleotide 5’-triphosphates (NTPs) occurs under either aerobic or anaerobic conditions.
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The short-chain dehydrogenases/reductases family (SDR) is a very large family of enzymes, most of which are known to be NAD- or NADP-dependent oxidoreductases. As the first member of this family to be characterised was Drosophila alcohol dehydrogenase, this family used to be called 'insect-type', or 'short-chain' alcohol dehydrogenases. Most members of this family are proteins of about 250 to 300 amino acid residues. Most dehydrogenases possess at least 2 domains, the first binding the coenzyme, often NAD, and the second binding the substrate.
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The Zeta-pan RNA motif is a conserved RNA structure that was discovered by bioinformatics. Zeta-pan motif RNAs are found in Zetaproteobacteria. Zeta-pan RNAs are consistently located upstream of "pan" operons, which contains genes involved in the synthesis of pantothenate, which is a vitamin that is a precursor of coenzyme A. This genetic arrangement is consistent with the idea that Zeta-pan RNAs function as cis-regulatory elements to regulate pantothenate synthesis. Another RNA motif was previously discovered that also is found upstream of pan operons.
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In addition to the anabolic carboxysomes, several catabolic BMCs have been characterized that participate in the heterotrophic metabolism via short-chain aldehydes; they are collectively termed metabolosomes. These BMCs share a common encapsulated chemistry driven by three core enzymes: aldehyde dehydrogenase, alcohol dehydrogenase, and phosphotransacylase. Because aldehydes can be toxic to cells and/or volatile, they are thought to be sequestered within the metabolosome. The aldehyde is initially fixed to coenzyme A by a NAD+-dependent aldehyde dehydrogenase, but these two cofactors must be recycled, as they apparently cannot cross the shell.
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One particular component, which LS9 has been successful in patenting is a key regulator in the initiation of fatty acid biosynthesis known as phosphopantetheinyl transferase (PPTase). This enzyme is responsible for transferring 4`-phosphopantetheine (4`-PP) from coenzyme A to a conserved serine residue on acyl carrier protein (ACP), which is responsible for shuttling around 4`-PP. This pathway is essential for the functioning of the Fatty Acid Synthase (FAS) enzyme and allows LS9 a certain degree of monopoly in fatty acid generation from microorganisms since it has patented such an integral component.
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The human NDUFA3 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. However, NDUFA3 is an accessory subunit of the complex that is believed not to be involved in catalysis. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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Coenzyme B12 – Theorized as the first occurrence of cobalt in a biological system Around 4–3 Ga, anaerobic prokaryotes began developing metal and organic cofactors for light absorption. They ultimately ended up making chlorophyll from Mg(II), as is found in cyanobacteria and plants, leading to modern photosynthesis. However, chlorophyll synthesis requires numerous steps. The process starts with uroporphyrin, a primitive precursor to the porphyrin ring which may be biotic or abiotic in origin, which is then modified in cells differently to make Mg, Fe, nickel (Ni), and cobalt (Co) complexes.
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Succinyl coenzyme A synthetase (SCS, also known as succinyl-CoA synthetase or succinate thiokinase or succinate-CoA ligase) is an enzyme that catalyzes the reversible reaction of succinyl-CoA to succinate. The enzyme facilitates the coupling of this reaction to the formation of a nucleoside triphosphate molecule (either GTP or ATP) from an inorganic phosphate molecule and a nucleoside diphosphate molecule (either GDP or ADP). It plays a key role as one of the catalysts involved in the citric acid cycle, a central pathway in cellular metabolism, and it is located within the mitochondrial matrix of a cell.
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The first protein structures of a dTDP-glucose 4,6-dehydratase (RmlB) were completed by Jim Thoden in the Hazel Holden lab (University of Wisconsin–Madison) and Simon Allard in the Jim Naismith lab (University of St Andrews). Further structural, mutagenic, and enzymatic studies by both groups, along with important mechanistic work by the W. Wallace Cleland and Perry Frey groups have led to a good understanding of this enzyme. In brief summary, the enzyme is a dimeric protein with a Rossmann fold; it uses the tightly bound coenzyme NAD+ for transiently oxidizing the substrate, activating it for the dehydration step.
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Pyruvate molecules produced by glycolysis are actively transported across the inner mitochondrial membrane, and into the matrix where they can either be oxidized and combined with coenzyme A to form CO2, acetyl-CoA, and NADH, or they can be carboxylated (by pyruvate carboxylase) to form oxaloacetate. This latter reaction ”fills up” the amount of oxaloacetate in the citric acid cycle, and is therefore an anaplerotic reaction, increasing the cycle's capacity to metabolize acetyl-CoA when the tissue's energy needs (e.g. in muscle) are suddenly increased by activity. In the citric acid cycle, all the intermediates (e.g.
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Mortensen et al. hypothesize that the dosage (100 mg three times daily) and the formulation of the Q10 used in the Q-SYMBIO clinical trial may have resulted in the patients reaching a required "therapeutic threshold in serum and tissue of CoQ10" needed to reduce the number of major adverse cardiovascular events. The formulation used in the trial has been demonstrated to have good bio-availability in controlled studies. In 2019, AL Mortensen, FL Rosenfeldt, and KJ Filipiak evaluated the treatment effect of Coenzyme Q10 adjuvant treatment in the European sub- population of the Q-SYMBIO clinical trial.
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A combination of required nutrients is used to satisfy the overall growth and development of the kitten body; there are many ingredients that kittens do not require, but are included in diet formulation to encourage healthy growth and development. These ingredients include: dried egg as a source of high quality protein and fatty acids, flaxseed, which is rich in omega-3 fatty acid and aids in digestion, calcium carbonate as a source of calcium, and calcium pantothenate (vitamin B5) that acts as a coenzyme in the conversion of amino acids and is important for healthy skin.
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It is important for patients with MADD to strictly avoid fasting to prevent hypoglycemia and crises of metabolic acidosis; for this reason, infants and small children should eat frequent meals. Patients with MADD can experience life-threatening metabolic crises precipitated by common childhood illnesses or other stresses on the body, so avoidance of such stresses is critical. Patients may be advised to follow a diet low in fat and protein and high in carbohydrates, particularly in severe cases. Depending on the subtype, riboflavin (100-400 mg/day), coenzyme Q10 (CoQ10), L-carnitine, or glycine supplements may be used to help restore energy production.
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Very-long-chain 3-oxoacyl-CoA synthase (, very-long-chain 3-ketoacyl-CoA synthase, very-long-chain beta-ketoacyl-CoA synthase, condensing enzyme, CUT1 (gene), CER6 (gene), FAE1 (gene), KCS (gene), ELO (gene)) is an enzyme with systematic name malonyl-CoA:very-long-chain acyl-CoA malonyltransferase (decarboxylating and thioester-hydrolysing). This enzyme catalyses the following chemical reaction : very-long-chain acyl-CoA + malonyl-CoA \rightleftharpoons very-long-chain 3-oxoacyl-CoA + CO2 \+ coenzyme A This is the first component of the elongase, a microsomal protein complex responsible for extending palmitoyl-CoA and stearoyl-CoA to very-long-chain acyl CoAs.
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In enzymology, an ADP-dependent medium-chain-acyl-CoA hydrolase () is an enzyme that catalyzes the chemical reaction :acyl-CoA + H2O \rightleftharpoons CoA + a carboxylate Thus, the two substrates of this enzyme are acyl-CoA and H2O, whereas its two products are CoA and carboxylate. This enzyme belongs to the family of hydrolases, specifically those acting on thioester bonds. The systematic name of this enzyme class is ADP-dependent-medium-chain-acyl-CoA hydrolase. Other names in common use include medium-chain acyl coenzyme A hydrolase, medium-chain acyl-CoA hydrolase, medium-chain acyl-thioester hydrolase, medium-chain hydrolase, and myristoyl-CoA thioesterase.
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Very long-chain acyl-CoA synthetase is an enzyme that in humans is encoded by the SLC27A2 gene. The protein encoded by this gene is an isozyme of long-chain fatty-acid-coenzyme A ligase family. Although differing in substrate specificity, subcellular localization, and tissue distribution, all isozymes of this family convert free long-chain fatty acids into fatty acyl-CoA esters, and thereby play a key role in lipid biosynthesis and fatty acid degradation. This isozyme activates long-chain, branched-chain and very long chain fatty acids containing 22 or more carbons to their CoA derivatives.
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The human NDUFA5 gene codes for the B13 subunit of complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. The NDUFA5 protein localizes to the mitochondrial inner membrane and it is thought to aid in this transfer of electrons. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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Xanthohumol is a prenylated chalconoid derived from a plant type III PKS, and is synthesized in the glandular trichromes of hop cones. L-Phenylalanine serves as the starting material, which is converted to cinnamic acid by the PLP-dependent phenylalanine ammonia lyase. Cinnamic acid is oxidized by cinnamate-4-hydroxylase and loaded onto Coenzyme A (CoA) by 4-coumarate CoA ligase to yield 4-hydroxy-cinnamoyl CoA, the starter unit for PKS extension. This molecule is extended three times with malonyl CoA, cyclized through a Claisen condensation, and aromatized through tautomerization to form naringenin chalcone (chalconaringenin).
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In enzymology, an acetate-CoA ligase (ADP-forming) () is an enzyme that catalyzes the chemical reaction :ATP + acetate + CoA \rightleftharpoons ADP + phosphate + acetyl-CoA The 3 substrates of this enzyme are ATP, acetate, and CoA, whereas its 3 products are ADP, phosphate, and acetyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is acetate:CoA ligase (ADP-forming). Other names in common use include acetyl-CoA synthetase (ADP-forming), acetyl coenzyme A synthetase (adenosine diphosphate- forming), and acetate thiokinase.
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In enzymology, a malyl-CoA lyase () is an enzyme that catalyzes the chemical reaction :(3S)-3-carboxy-3-hydroxypropanoyl-CoA \rightleftharpoons acetyl-CoA + glyoxylate Hence, this enzyme has one substrate, (3S)-3-carboxy-3-hydroxypropanoyl-CoA, and two products, acetyl-CoA and glyoxylate. This enzyme belongs to the family of lyases, specifically the oxo- acid-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is (3S)-3-carboxy-3-hydroxypropanoyl-CoA glyoxylate-lyase (acetyl-CoA-forming). Other names in common use include malyl-coenzyme A lyase, and (3S)-3-carboxy-3-hydroxypropanoyl-CoA glyoxylate-lyase.
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Citrate synthase's 437 amino acid residues are organized into two main subunits, each consisting of 20 alpha- helices. These alpha helices compose approximately 75% of citrate synthase's tertiary structure, while the remaining residues mainly compose irregular extensions of the structure, save a single beta-sheet of 13 residues. Between these two subunits, a single cleft exists containing the active site. Two binding sites can be found therein: one reserved for citrate or oxaloacetate and the other for Coenzyme A. The active site contains three key residues: His274, His320, and Asp375 that are highly selective in their interactions with substrates.
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Recently, a second parallel protective pathway was independently discovered by two labs that involves the oxidoreductase FSP1/AIFM2. Their findings indicate that FSP1/AIFM2 enzymatically reduces non- mitochondrial Coenzyme Q10, thereby generating a potent lipophilic antioxidant to suppresses the propagation of lipid peroxides. A similar mechanism for a cofactor moonlighting as a diffusable antioxidant was discovered in the same year for tetrahydrobiopterin/BH4, a product of the rate limiting enzyme GCH1. Human prostate cancer cells undergoing ferroptosis Small molecules such as erastin, sulfasalazine, sorafenib, altretamine, RSL-3, ML-162 and ML-210 are known inhibitors of this tumor cell growth and induce ferroptosis.
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2-hydroxypropyl-CoM lyase (, epoxyalkane:coenzyme M transferase, epoxyalkane:CoM transferase, epoxyalkane:2-mercaptoethanesulfonate transferase, coenzyme M-epoxyalkane ligase, epoxyalkyl:CoM transferase, epoxypropane:coenzyme M transferase, epoxypropyl:CoM transferase, EaCoMT, 2-hydroxypropyl-CoM:2-mercaptoethanesulfonate lyase (epoxyalkane-ring- forming), (R)-2-hydroxypropyl-CoM 2-mercaptoethanesulfonate lyase (cyclizing, (R)-1,2-epoxypropane-forming)) is an enzyme with systematic name (R)-(or (S)-)2-hydroxypropyl-CoM:2-mercaptoethanesulfonate lyase (epoxyalkane-ring- forming). This enzyme catalyses the following chemical reaction : (1) (R)-2-hydroxypropyl-CoM \rightleftharpoons (R)-1,2-epoxypropane + HS-CoM : (2) (S)-2-hydroxypropyl-CoM \rightleftharpoons (S)-1,2-epoxypropane + HS-CoM This enzyme requires zinc.
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The UQCRFS1 gene encodes for an iron-sulfur protein, which is an essential subunit of the Ubiquinol Cytochrome c Reductase or Complex III in the mitochondrial respiratory chain. Complex III is responsible for electron transfer from coenzyme Q to cytochrome c as well as the proton transfer from the extracellular matrix to the intermembrane space which leads to ATP-coupled electrochemical potential generation. Incorporation of the subunit UQCRFS1 is the second to last step in complex III assembly. Once it is incorporated, UQCRFS1 undergoes proteolytic processing, which is essential for the correct insertion into Complex III.
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An example of an "inverse" α secondary kinetic isotope effect can be seen in the work of Fitzpatrick and Kurtz who used such an effect to distinguish between two proposed pathways for the reaction of d-amino acid oxidase with nitroalkane anions. Path A involved a nucleophilic attack on the coenzyme FAD, while path B involves a free- radical intermediate. As path A results in the intermediate carbon changing hybridization from sp2 to sp3 an "inverse" a SKIE is expected. If path B occurs then no SKIE should be observed as the free radical intermediate does not change hybridization.
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The FOXRED1 gene encodes an enzyme that is localized in the mitochondria and which helps in the assembly and stabilization of NADH:ubiquinone oxidoreductase, a large multi-subunit enzyme in the mitochondrial respiratory chain. NADH:ubiquinone oxidoreductase (complex I) is involved in several physiological activities in the cell, including metabolite transport and ATP synthesis. Complex I catalyzes the transfer of electrons from NADH to ubiquinone (coenzyme Q) in the first step of the mitochondrial respiratory chain, resulting in the translocation of protons across the inner mitochondrial membrane. The encoded protein of FOXRED1 is an oxidoreductase and complex I-specific molecular chaperone.
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Mutations in the ACADVL gene lead to inadequate levels of an enzyme called very long-chain acyl-coenzyme A (CoA) dehydrogenase. Without this enzyme, long-chain fatty acids from food and fats stored in the body cannot be degraded and processed. As a result, these fatty acids are not converted into energy, which can lead to characteristic signs and symptoms of this disorder, such as lethargy and hypoglycemia. Levels of very long-chain fatty acids or partially degraded fatty acids may build up in tissues and can damage the heart, liver, and muscles, causing more serious complications.
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Acyl-coenzyme A thioesterase 11 also known as StAR-related lipid transfer protein 14 (STARD14) is an enzyme that in humans is encoded by the ACOT11 gene. This gene encodes a protein with acyl-CoA thioesterase activity towards medium (C12) and long-chain (C18) fatty acyl-CoA substrates which relies on its StAR-related lipid transfer domain. Expression of a similar murine protein in brown adipose tissue is induced by cold exposure and repressed by warmth. Expression of the mouse protein has been associated with obesity, with higher expression found in obesity-resistant mice compared with obesity-prone mice.
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Mutant SPT mediates the condensation not only of its normal substrate serine, but also of alanine or glycine, with palmitoyl-coenzyme A. The reactions lead to the formation of two aberrant sphingolipid metabolites 1-deoxy-sphinganine and 1-deoxymethyl-sphinganine, respectively. As the metabolites lack a hydroxyl group that is required for their further conversion and degradation, they accumulate inside the cell. The metabolites have been shown to be more toxic to sensory neurons than to motor neurons. They accumulate in the peripheral nervous system where HSAN manifest, but not in the central nervous system in mice bearing a HSAN IA-associated mutation.
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Cordero Hardy earned her doctorate degree in physiology. Her research into Vitamin E helped other scientists understand how vitamins affect the human body. According to Cordero Hardy's findings, Vitamin E is an antioxidant that has been effective in treating chronic hepatitis B, as stated in New Medicine: Complete Family Health Guide. Vitamin E has also exhibited the ability to protect the liver from damage that can occur in people with hepatitis C. Cordero Hardy was the Project Director of the program which studied the effect of supplemental antioxidants Vitamin C, Vitamin E, and Coenzyme Q10 for the prevention and treatment of cardiovascular disease.
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Some non-proteinogenic amino acids are not found in proteins. Examples include 2-aminoisobutyric acid and the neurotransmitter gamma-aminobutyric acid. Non- proteinogenic amino acids often occur as intermediates in the metabolic pathways for standard amino acids – for example, ornithine and citrulline occur in the urea cycle, part of amino acid catabolism (see below). A rare exception to the dominance of α-amino acids in biology is the β-amino acid beta alanine (3-aminopropanoic acid), which is used in plants and microorganisms in the synthesis of pantothenic acid (vitamin B5), a component of coenzyme A.
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In enzymology, a beta-ureidopropionase () is an enzyme that catalyzes the chemical reaction :N-carbamoyl-beta-alanine + H2O \rightleftharpoons beta- alanine + CO2 \+ NH3 Thus, the two substrates of this enzyme are N-carbamoyl- beta-alanine and H2O, whereas its 3 products are beta-alanine, CO2, and NH3. This enzyme belongs to the family of hydrolases, those acting on carbon- nitrogen bonds other than peptide bonds, specifically in linear amides. The systematic name of this enzyme class is N-carbamoyl-beta-alanine amidohydrolase. This enzyme participates in 3 metabolic pathways: pyrimidine metabolism, beta-alanine metabolism, and pantothenate and coenzyme A biosynthesis.
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Biotin is a coenzyme for five carboxylases in the human body (propionyl-CoA carboxylase, methylcrotonyl-CoA carboxylase, pyruvate carboxylase, and 2 forms of acetyl-CoA carboxylase.) Therefore, biotin is essential for amino acid catabolism, gluconeogenesis, and fatty acid metabolism. Biotin is also necessary for gene stability because it is covalently attached to histones. Biotinylated histones play a role in repression of transposable elements and some genes. Normally, the amount of biotin in the body is regulated by dietary intake, biotin transporters (monocarboxylate transporter 1 and sodium-dependent multivitamin transporter), peptidyl hydrolase biotinidase (BTD), and the protein ligase holocarboxylase synthetase.
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Other cofactors were identified throughout the early 20th century, with ATP being isolated in 1929 by Karl Lohmann, and coenzyme A being discovered in 1945 by Fritz Albert Lipmann. The functions of these molecules were at first mysterious, but, in 1936, Otto Heinrich Warburg identified the function of NAD+ in hydride transfer. This discovery was followed in the early 1940s by the work of Herman Kalckar, who established the link between the oxidation of sugars and the generation of ATP. This confirmed the central role of ATP in energy transfer that had been proposed by Fritz Albert Lipmann in 1941.
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Data on the metabolism of CoQ10 in animals and humans are limited. A study with 14C-labeled CoQ10 in rats showed most of the radioactivity in the liver two hours after oral administration when the peak plasma radioactivity was observed, but CoQ9 (with only 9 isoprenyl units) is the predominant form of coenzyme Q in rats. It appears that CoQ10 is metabolised in all tissues, while a major route for its elimination is biliary and fecal excretion. After the withdrawal of CoQ10 supplementation, the levels return to normal within a few days, irrespective of the type of formulation used.
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Soon they noted that Q-275 and substance SA studied in England may be the same compound. This was confirmed later that year and Q-275/substance SA was renamed ubiquinone as it was an ubiquitous quinone that could be found from all animal tissues. In 1958, its full chemical structure was reported by D. E. Wolf and colleagues working under Karl Folkers at Merck in Rahway. Later that year D. E. Green and colleagues belonging to the Wisconsin research group suggested that ubiquinone should be called either mitoquinone or coenzyme Q due to its participation to the mitochondrial electron transport chain.
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This second subclass contains an addition subunit (PyrK) containing an iron-sulfur cluster and a flavin adenine dinucleotide (FAD). Meanwhile, Class 2 DHODHs use coenzyme Q/ubiquinones for their oxidant. In higher eukaryotes, this class of DHODH contains an N-terminal bipartite signal comprising a cationic, amphipathic mitochondrial targeting sequence of about 30 residues and a hydrophobic transmembrane sequence. The targeting sequence is responsible for this protein’s localization to the IMM, possibly from recruiting the import apparatus and mediating ΔΨ-driven transport across the inner and outer mitochondrial membranes, while the transmembrane sequence is essential for its insertion into the IMM.
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Despite the similarity in how proteins bind the two coenzymes, enzymes almost always show a high level of specificity for either NAD or NADP. This specificity reflects the distinct metabolic roles of the respective coenzymes, and is the result of distinct sets of amino acid residues in the two types of coenzyme-binding pocket. For instance, in the active site of NADP-dependent enzymes, an ionic bond is formed between a basic amino acid side-chain and the acidic phosphate group of NADP. On the converse, in NAD-dependent enzymes the charge in this pocket is reversed, preventing NADP from binding.
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The coenzyme NAD is also consumed in ADP-ribose transfer reactions. For example, enzymes called ADP- ribosyltransferases add the ADP-ribose moiety of this molecule to proteins, in a posttranslational modification called ADP-ribosylation. ADP-ribosylation involves either the addition of a single ADP-ribose moiety, in mono-ADP- ribosylation, or the transferral of ADP-ribose to proteins in long branched chains, which is called poly(ADP-ribosyl)ation. Mono-ADP-ribosylation was first identified as the mechanism of a group of bacterial toxins, notably cholera toxin, but it is also involved in normal cell signaling.
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Histone acetyltransferase (HAT) removes the acetyl group from acetyl-CoA and transfers it the N-terminal tail of chromatin histones. In the reverse reaction, histone deacetylase (HDAC) removes the acetyl group from the histone tails and binds it to coenzyme A to form acetyl-CoA. Some coactivators indirectly regulate gene expression by binding to an activator and inducing a conformational change that then allows the activator to bind to the DNA enhancer or promoter sequence. Once the activator-coactivator complex binds to the enhancer, RNA polymerase II and other general transcription machinery are recruited to the DNA and transcription begins.
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Carbon fixation is the incorporation of inorganic carbon into organic matter. Unlike the surface of the planet where light is a major source of energy for carbon fixation, hydrothermal vent chemolithotrophic bacteria rely on chemical oxidation to obtain the energy required. Fixation of CO2 is observed in members of gammaproteobacteria, epsilonproteobacteria, alphaproteobacteria, and members of Archaea domain at hydrothermal vents. Four major metabolic pathways for carbon fixation found in microbial vent communities include the Calvin–Benson–Bassham (CBB) cycle, reductive tricarboxylic acid (rTCA) cycle, 3-hydroxypropionate (3-HP) cycle and reductive acetyl coenzyme A (acetyl-CoA) pathway.
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Generally the carbohydrate part(s) play an integral role in the function of a glycoconjugate; prominent examples of this are NCAM and blood proteins where fine details in the carbohydrate structure determine cell binding or not or lifetime in circulation. Although the important molecular species DNA, RNA, ATP, cAMP, cGMP, NADH, NADPH, and coenzyme A all contain a carbohydrate part, generally they are not considered as glycoconjugates. Glycocojugates is covalent linking of carbohydrates antigens to protein scaffolds with goal of achieving a long term immunological response in body. Immunization with glycoconjugates successfully induced long term immune memory against carbohydrates antigens.
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Adenosine 3',5'-bisphosphate is a form of an adenosine nucleotide with two phosphate groups attached to different carbons in the ribose ring. This is distinct from adenosine diphosphate, where the two phosphate groups are attached in a chain to the 5' carbon atom in the ring. Adenosine 3',5'-bisphosphate is produced as a product of sulfotransferase enzymes from the donation of a sulfate group from the coenzyme 3'-phosphoadenosine-5'-phosphosulfate. This product is then hydrolysed by 3'(2'),5'-bisphosphate nucleotidase to give adenosine monophosphate, which can then be recycled into adenosine triphosphate.
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In enzymology, an isopenicillin N N-acyltransferase () is an enzyme that catalyzes the chemical reaction :phenylacetyl-CoA + isopenicillin N + H2O \rightleftharpoons CoA + penicillin G + L-2-aminohexanedioate The 3 substrates of this enzyme are phenylacetyl-CoA, isopenicillin N, and H2O, whereas its 3 products are CoA, penicillin G, and L-2-aminohexanedioate. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acyl-CoA:isopenicillin N N-acyltransferase. Other names in common use include acyl-coenzyme A:isopenicillin N acyltransferase, and isopenicillin N:acyl-CoA: acyltransferase.
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The opposite is seen with lower gut microbiome diversity, and these microbiotas may work together to create host food cravings. Additionally, the liver plays a dominant role in blood glucose homeostasis by maintaining a balance between the uptake and storage of glucose through the metabolic pathways of glycogenesis and gluconeogenesis. Intestinal lipids regulate glucose homeostasis involving a gut-brain-liver axis. The direct administration of lipids into the upper intestine increases the long chain fatty acyl-coenzyme A (LCFA-CoA) levels in the upper intestines and suppresses glucose production even under subdiaphragmatic vagotomy or gut vagal deafferentation.
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In enzymology, a CoA-disulfide reductase () is an enzyme that catalyzes the chemical reaction :2 CoA + NAD(P)+ \rightleftharpoons CoA-disulfide + NAD(P)H + H+ The 3 substrates of this enzyme are CoA, NAD+, and NADP+, whereas its 4 products are CoA-disulfide, NADH, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is CoA:NAD(P)+ oxidoreductase. Other names in common use include CoA- disulfide reductase (NADH2), NADH2:CoA-disulfide oxidoreductase, CoA:NAD+ oxidoreductase, CoADR, and coenzyme A disulfide reductase.
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The exact cause for the varied collection of symptoms found in the different ALD phenotypes is not clear. The white matter of the brain, the Leydig cells of the testes and the adrenal cortex are the most severely affected systems. The excess VLCFA can be detected in almost all tissues of the body, despite the localization of symptoms. The lack of Coenzyme A does not permit the disintegration of the VLCFA, accumulating the same in the white matter, adrenal glands, and the testes more specifically in the Leydig cells not allowing the proper function of this organs.
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Long chain fatty acids (more than 14 carbon) need to be converted to fatty acyl-CoA in order to pass across the mitochondria membrane. Fatty acid catabolism begins in the cytoplasm of cells as acyl-CoA synthetase uses the energy from cleavage of an ATP to catalyze the addition of coenzyme A to the fatty acid. The resulting acyl-CoA cross the mitochondria membrane and enter the process of beta oxidation. The main products of the beta oxidation pathway are acetyl-CoA (which is used in the citric acid cycle to produce energy), NADH and FADH.
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Mutations of the ACADS gene are associated with deficiency of the short-chain acyl-coenzyme A dehydrogenase protein (SCADD); this is also known as butyryl-CoA dehydrogenase deficiency. Many mutations have been identified in specific populations, and large-scale studies have been performed to determine the allelic and genotypic frequency for the defective gene. As short-chain acyl-CoA dehydrogenase is involved in beta-oxidation, a deficiency in this enzyme is marked by an increased amount of fatty acids. This deficiency is characterized by the presence of increased butyrylcarnitine (C4) in blood plasma, and increased ethylmalonic acid (EMA) concentrations in urine.
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Vitamin B12 (cobalamin), for example, plays a crucial role in the human body, while coenzyme B12, its derivative, is found in the metabolisms of every type of cell in our bodies. Its presence affects the synthesis and regulation of cellular DNA as well as taking part in fatty acid synthesis and energy production. Cofactors are required by many important metabolic pathways, and it is possible for the concentrations of a single type of cofactor to affect the fluxes of many different pathways . Minerals and metallic ions that organisms uptake through their diet provide prime examples of inorganic cofactors.
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Coenzyme A (CoA) and acetyl-CoA are two intermediate metabolites, most notably found in the Citric Acid Cycle, which participate in over 100 different reactions in the metabolism of microorganisms. Recent experiments have shown that over expression of the enzyme pantothenate kinase and supplementation of pantothenic acid in the CoA biosynthesis pathway have allowed adjustments of both CoA and acetyl-CoA fluxes. This increased concentration of cofactors resulted in an increased carbon flux in the isoamyl acetate synthesis pathway, increase the production efficiency of isoamyl acetate. Isoamyl acetate is used industrially for artificial flavoring and for testing the effectiveness of respirators.
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The oxidation of acetyl coenzyme A (acetyl-CoA) in the mitochondrial matrix is coupled to the reduction of a carrier molecule such as nicotinamide adenine dinucleotide (NAD) and flavin adenine dinucleotide (FAD). The carriers pass electrons to the electron transport chain (ETC) in the inner mitochondrial membrane, which in turn pass them to other proteins in the ETC. The energy available in the electrons is used to pump protons from the matrix across the stroma, storing energy in the form of a transmembrane electrochemical gradient. The protons move back across the inner membrane through the enzyme ATP synthase.
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All ACPS enzymes known so far are evolutionally related to each other in a single superfamily of proteins. It transfers a 4'-phosphopantetheine (4'-PP) moiety from coenzyme A (CoA) to an invariant serine in an acyl carrier protein (ACP), a small protein responsible for acyl group activation in fatty acid biosynthesis. This post-translational modification renders holo-ACP capable of acyl group activation via thioesterification of the cysteamine thiol of 4'-PP. This superfamily consists of two subtypes: the trimeric ACPS type such as E. coli ACPS and the monomeric Sfp (PCP-synthesizing) type such as B. subtilis SFP.
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These organisms are facultative anaerobes. To avoid the overproduction of NADH, obligately fermentative organisms usually do not have a complete citric acid cycle. Instead of using an ATP synthase as in respiration, ATP in fermentative organisms is produced by substrate-level phosphorylation where a phosphate group is transferred from a high-energy organic compound to ADP to form ATP. As a result of the need to produce high energy phosphate-containing organic compounds (generally in the form of Coenzyme A-esters) fermentative organisms use NADH and other cofactors to produce many different reduced metabolic by-products, often including hydrogen gas ().
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Long-chain-fatty-acid—CoA ligase 5 is an enzyme that in humans is encoded by the ACSL5 gene. The protein encoded by this gene is an isozyme of the long- chain fatty-acid-coenzyme A ligase family. Although differing in substrate specificity, subcellular localization, and tissue distribution, all isozymes of this family convert free long-chain fatty acids into fatty acyl-CoA esters, and thereby play a key role in lipid biosynthesis and fatty acid degradation. This isozyme is highly expressed in uterus and spleen, and in trace amounts in normal brain, but has markedly increased levels in malignant gliomas.
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In molecular biology, the HMG-CoA reductase family is a family of enzymes which participate in the mevalonate pathway, the metabolic pathway that produces cholesterol and other isoprenoids. There are two distinct classes of hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase enzymes: class I consists of eukaryotic and most archaeal enzymes , while class II consists of prokaryotic enzymes . Class I HMG-CoA reductases catalyse the NADP-dependent synthesis of mevalonate from 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA). In vertebrates, membrane-bound HMG-CoA reductase is the rate-limiting enzyme in the biosynthesis of cholesterol and other isoprenoids.
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Oxidative deamination is a form of deamination that generates α-keto acids and other oxidized products from amine-containing compounds, and occurs only in the liver. Oxidative deamination is an important step in the catabolism of amino acids, generating a more metabolizable form of the amino acid, and also generating ammonia as a toxic byproduct. The ammonia generated in this process can then be neutralized into urea via the urea cycle. Much of the oxidative deamination occurring in cells involves the amino acid glutamate, which can be oxidatively deaminated by the enzyme glutamate dehydrogenase (GDH), using NAD or NADP as a coenzyme.
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In enzymology, a propanediol dehydratase () is an enzyme that catalyzes the chemical reaction :propane-1,2-diol \rightleftharpoons propanal + H2O Hence, this enzyme has one substrate, 1,2-propanediol, and two products, propanal and H2O. This enzyme belongs to the family of lyases, specifically the hydro- lyases, which cleave carbon-oxygen bonds. The systematic name of this enzyme class is propane-1,2-diol hydro-lyase (propanal-forming). Other names in common use include meso-2,3-butanediol dehydrase, diol dehydratase, DL-1,2-propanediol hydro-lyase, diol dehydrase, adenosylcobalamin-dependent diol dehydratase, propanediol dehydrase, coenzyme B12-dependent diol dehydrase, 1,2-propanediol dehydratase, dioldehydratase, and propane-1,2-diol hydro-lyase.
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The two molecules joined together that make up Acetyl CoA are acetate and coenzyme A (CoA). The complete reaction with all the substrates and products included is: :ATP + Acetate + CoA <=> AMP + Pyrophosphate + Acetyl-CoA KEGG Once acetyl-CoA is formed it can be used in the TCA cycle in aerobic respiration to produce energy and electron carriers. This is an alternate method to starting the cycle, as the more common way is producing acetyl-CoA from pyruvate through the pyruvate dehydrogenase complex. The enzyme's activity takes place in the mitochondrial matrix so that the products are in the proper place to be used in the following metabolic steps.
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In the European sub-group, ejection fraction and NYHA classification improved significantly, and both all-cause and cardiovascular mortality decreased significantly. The researchers concluded that the evidence from the European sub-group analysis re-affirms the evidence of the therapeutic efficacy of the CoQ10 adjuvant therapy despite the greater adherence to guideline-directed therapy in the European sub-group than in the entire group of chronic heart failure patients. The European sub- group study provides confirmatory evidence that the treatment with 300 mg/day of Coenzyme Q10 in additional to conventional heart failure therapy is safe, well tolerated, and effective in improving the symptoms and survival of chronic heart failure patients.
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The human NDUFA8 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The human NDUFA12 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The protein encoded by this gene is a nuclear receptor that is closely related to the estrogen receptor. Results of both in vitro and in vivo studies suggest that ERRα is required for the activation of mitochondrial genes as well as increased mitochondrial biogenesis. This protein acts as a site-specific (consensus TNAAGGTCA) transcription regulator and has been also shown to interact with estrogen and the transcription factor TFIIB by direct protein-protein contact. The binding and regulatory activities of this protein have been demonstrated in the regulation of a variety of genes including lactoferrin, osteopontin, medium- chain acyl coenzyme A dehydrogenase (MCAD) and thyroid hormone receptor genes.
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A total of 36 genes are significantly enriched in ε-cells that aid in proteinase inhibition, processing of hormones, cell migration, and immune activity that differentiates them from α-, β-, δ- and PP-cells. Additionally, the secretory vesicles of ε-cells (110±3 nm) are much smaller than those of α-cells (185±7 nm). Unlike the other pancreatic islet cells, ε-cells also do not produce other pancreatic hormones (insulin, glucagon, homeostatic) and they do not express the CART peptide. Examples of specific genes that influence ε-cells are acyl-coenzyme A synthetase long chain family member 1 (ACSL1) and defensin beta 1.
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Photoredox enabled biocatalysis reactions fall into two categories: # Internal coenzyme/cofactor photocatalyst # External photocatalyst Certain common hydrogen atom transfer (HAT) cofactors (NADPH and Flavin) can operate as single electron transfer (SET) reagents. Although these species are capable of HAT without irradiation, their redox potentials are enhance by nearly 2.0 V upon visible light irradiation. When paired with their respective enzymes (typically ene-reductases) This phenomenon has been utilized by chemists to develop enantioselective reduction methodologies. For example medium sized lactams can be synthesized in the chiral environment of an ene-reductase through a reductive, baldwin favored, radical cyclization terminated by enatioselective HAT from NADPH.
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Pyruvate molecules produced by glycolysis are actively transported across the inner mitochondrial membrane, and into the matrix where they can either be oxidized and combined with coenzyme A to form CO2, acetyl-CoA, and NADH, or they can be carboxylated (by pyruvate carboxylase) to form oxaloacetate. This latter reaction "fills up" the amount of oxaloacetate in the citric acid cycle, and is therefore an anaplerotic reaction (from the Greek meaning to "fill up"), increasing the cycle’s capacity to metabolize acetyl-CoA when the tissue's energy needs (e.g. in heart and skeletal muscle) are suddenly increased by activity. In the citric acid cycle all the intermediates (e.g.
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Mutations in the HADHA gene lead to inadequate levels of an enzyme called long-chain 3-hydroxyacyl-coenzyme A (CoA) dehydrogenase, which is part of a protein complex known as mitochondrial trifunctional protein. Long-chain fatty acids from food and body fat cannot be metabolized and processed without sufficient levels of this enzyme. As a result, these fatty acids are not converted to energy, which can lead to characteristic features of this disorder, such as lethargy and hypoglycemia. Long-chain fatty acids or partially metabolized fatty acids may build up in tissues and damage the liver, heart, retina, and muscles, causing more serious complications.
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The human NDUFA10 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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Three mechanisms of resistance to chloramphenicol are known: reduced membrane permeability, mutation of the 50S ribosomal subunit, and elaboration of chloramphenicol acetyltransferase. It is easy to select for reduced membrane permeability to chloramphenicol in vitro by serial passage of bacteria, and this is the most common mechanism of low-level chloramphenicol resistance. High-level resistance is conferred by the cat-gene; this gene codes for an enzyme called chloramphenicol acetyltransferase, which inactivates chloramphenicol by covalently linking one or two acetyl groups, derived from acetyl-S-coenzyme A, to the hydroxyl groups on the chloramphenicol molecule. The acetylation prevents chloramphenicol from binding to the ribosome.
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The human NDUFA6 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The human NDUFA4L2 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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In enzymology, a geranoyl-CoA carboxylase () is an enzyme that catalyzes the chemical reaction :ATP + geranoyl-CoA + HCO3\- \rightleftharpoons ADP + phosphate + 3-(4-methylpent-3-en-1-yl)pent-2-enedioyl-CoA The 3 substrates of this enzyme are ATP, geranoyl-CoA, and HCO3-, whereas its 3 products are ADP, phosphate, and 3-(4-methylpent-3-en-1-yl)pent-2-enedioyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon–carbon bonds. The systematic name of this enzyme class is geranoyl-CoA:carbon-dioxide ligase (ADP-forming). Other names in common use include geranoyl coenzyme A carboxylase, and geranyl-CoA carboxylase.
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In enzymology, a glutaconyl-CoA decarboxylase () is an enzyme that catalyzes the chemical reaction :4-carboxybut-2-enoyl-CoA \rightleftharpoons but-2-enoyl-CoA + CO2 Hence, this enzyme has one substrate, 4-carboxybut-2-enoyl-CoA, and two products, but-2-enoyl-CoA and CO2. This enzyme belongs to the family of lyases, specifically the carboxy-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is 4-carboxybut-2-enoyl-CoA carboxy-lyase (but-2-enoyl-CoA-forming). Other names in common use include glutaconyl coenzyme A decarboxylase, pent-2-enoyl-CoA carboxy-lyase, and 4-carboxybut-2-enoyl-CoA carboxy-lyase.
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Vitamin B2 (riboflavin) is a constituent of FMN and FAD which are necessary for many redox reactions. Vitamin B3 (nicotinic acid or niacin), synthesized from tryptophan is a component of the coenzymes NAD and NADP which in turn are required for electron transport in the Krebs cycle, oxidative phosphorylation, as well as many other redox reactions. Vitamin B5 (pantothenic acid) is a constituent of coenzyme A, a basic component of carbohydrate and amino acid metabolism as well as the biosynthesis of fatty acids and polyketides. Vitamin B6 (pyridoxol, pyridoxal, and pyridoxamine) as pyridoxal 5′-phosphate is a cofactor for many enzymes especially transaminases involve in amino acid metabolism.
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Carboxysomes are bacterial microcompartments found in many autotrophic bacteria such as Cyanobacteria, Knallgasbacteria, Nitroso- and Nitrobacteria. They are proteinaceous structures resembling phage heads in their morphology and contain the enzymes of carbon dioxide fixation in these organisms (especially ribulose bisphosphate carboxylase/oxygenase, RuBisCO, and carbonic anhydrase). It is thought that the high local concentration of the enzymes along with the fast conversion of bicarbonate to carbon dioxide by carbonic anhydrase allows faster and more efficient carbon dioxide fixation than possible inside the cytoplasm. Similar structures are known to harbor the coenzyme B12-containing glycerol dehydratase, the key enzyme of glycerol fermentation to 1,3-propanediol, in some Enterobacteriaceae (e. g. Salmonella).
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In the first, pantethine serves as the precursor for synthesis of coenzyme A. CoA is involved in the transfer of acetyl groups, in some instances to attach to proteins closely associated with activating and deactivating genes. By this theory, either the genes responsible for cholesterol and triglyceride synthesis are suppressed or the genes governing the catabolism of compounds are turned on. In the second theory, pantethine is converted to two pantetheine molecules which are in turn metabolized to form two pantethenic acid and two cysteamine molecules. Cysteamine is theorized to bind to and thus inactivate sulfur-containing amino acids in liver enzymes involved in the production of cholesterol and triglycerides.
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A proteomics approach using two-dimensional chromatography-mass spectrometry found major phospholipids were archaeol phosphatidylglycerol, archaeol phosphatidylinositol, hydroxyarchaeol phosphatidylglycerol, and hydroxyarchaeol phosphatidylinositol. All phospholipid classes contained a series of unsaturated analogues, with the degree of unsaturation dependent on phospholipid class. The proportion of unsaturated lipids from cells grown at 4 °C was significantly higher than for cells grown at 23 °C. 3-Hydroxy-3-methylglutaryl coenzyme A synthase, farnesyl diphosphate synthase, and geranylgeranyl diphosphate synthase were identified in the expressed proteome, and most genes involved in the mevalonate pathway and processes leading to the formation of phosphatidylinositol and phosphatidylglycerol were identified in the genome sequence.
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The human NDUFA9 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The human NDUFA2 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. NDUFA2 is an accessory subunit of Complex I that is believed not to be involved in catalysis but may be involved in regulating Complex I activity or its assembly via assistance in redox processes. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2).
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The enzyme is composed of two subunits in green plants (including Chlorophyceae, Marchantimorpha, Bryopsida, Pinaceae, monocotyledons, and eudicots), species of fungi, glaucophytes, Chlamydomonas, and prokaryotes. Animal ACL enzymes are homomeric; a fusion of the ACLA and ACLB genes probably occurred early in the evolutionary history of this kingdom. The mammalian ATP citrate lyase has a N-terminal citrate-binding domain that adopts a Rossmann fold, followed by a CoA binding domain and CoA- ligase domain and finally a C-terminal citrate synthase domain. The cleft between the CoA binding and citrate synthase domains forms the active site of the enzyme, where both citrate and acetyl-coenzyme A bind.
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Chemical structure of palmitoyl-CoA, a fatty acyl-CoA ester Fatty acyl-CoA esters are fatty acid derivatives formed of one fatty acid, a 3'-phospho-AMP linked to phosphorylated pantothenic acid (vitamin B5) and cysteamine. Long- chain acyl-CoA esters are substrates for a number of important enzymatic reactions and play a central role in the regulation of metabolism as allosteric regulators of several enzymes. To participate in specific metabolic processes, fatty acids must first be activated by being joined in thioester linkage (R-CO-SCoA) to the -SH group of coenzyme A, where R is a fatty carbon chain. The thioester bond is a high energy bond.
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Hastings began his graduate studies at Princeton University in 1948 in the laboratory of E. Newton Harvey, the world leader of luminescence studies at the time, and focused on the role of oxygen in the luminescence of bacteria, fireflies, ostracod crustaceans and fungi. He received his PhD in 1951. He then joined the lab of William D. McElroy, another student of Harvey’s, at Johns Hopkins University where he discovered both the stimulatory effects of coenzyme A and gating control by oxygen of firefly luminescence, and that flavin is a substrate in bacterial luminescence. In 1953 he joined the faculty in the Department of Biological Sciences at Northwestern University.
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This result provides further evidence that the clock gene has a profound impact on metabolic processes in mice. It has since been discovered that metabolism itself plays a role in regulating the clock. In 2009, Joseph Bass in collaboration with Takahashi's group discovered that nicotinamide phosphoribosyltransferase (NAMPT) mediated synthesis of metabolic coenzyme nicotinamide adenine dinucleotide (NAD+), which both oscillate on a daily cycle, may play an important role in regulating circadian activity. By measuring the oscillations of NAMPT and NAD+ levels in the livers of both wild-type and mutant mice they determined that oscillations in NAMPT regulated NAD+ which in turn regulated the deacetylase SIRT1.
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PLP acts as a coenzyme in all transamination reactions, and in certain decarboxylation, deamination, and racemization reactions of amino acids. The aldehyde group of PLP forms a Schiff-base linkage (internal aldimine) with the ε-amino group of a specific lysine group of the aminotransferase enzyme. The α-amino group of the amino acid substrate displaces the ε-amino group of the active-site lysine residue in a process known as transaldimination. The resulting external aldimine can lose a proton, carbon dioxide, or an amino acid sidechain to become a quinonoid intermediate, which in turn can act as a nucleophile in several reaction pathways.
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Plant lipid transfer proteins, also known as plant LTPs or PLTPs, are a group of highly-conserved proteins of about 7-9kDa found in higher plant tissues. As its name implies, lipid transfer proteins are responsible for the shuttling of phospholipids and other fatty acid groups between cell membranes. LTPs are divided into two structurally related subfamilies according to their molecular masses: LTP1s (9 kDa) and LTP2s (7 kDa). Various LTPs bind a wide range of ligands, including fatty acids (FAs) with a C10–C18 chain length, acyl derivatives of coenzyme A (CoA), phospho- and galactolipids, prostaglandin B2, sterols, molecules of organic solvents, and some drugs.
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Biotin can be provided in feline diets through the addition of cooked eggs, liver, milk, legumes or nuts. Microorganisms living in the gastrointestinal tracts of cats are also able to synthesize and supply an alternative source of biotin if proper nutritional requirements are met. Its main function in metabolism is to operate as a coenzyme for essential carboxylation reactions throughout the body1 however it has also been shown to aid in the management of certain skin diseases in cats. Biotin is recommended by AAFCO to be included in feline diets at a minimum level of 0.07 mg/kg on a dry matter basis throughout all stages of development.
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They are therefore always released into the blood by the liver together with newly produced glucose after the liver glycogen stores have been depleted (these glycogen stores are depleted within the first 24 hours of fasting). When two acetyl-CoA molecules lose their -CoAs (or coenzyme A groups), they can form a (covalent) dimer called acetoacetate. β-hydroxybutyrate is a reduced form of acetoacetate, in which the ketone group is converted into an alcohol (or hydroxyl) group (see illustration on the right). Both are 4-carbon molecules that can readily be converted back into acetyl-CoA by most tissues of the body, with the notable exception of the liver.
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Tabtoxin resistance protein (TTR) is an enzyme that catalyzes the acetylation of tabtoxin rendering tabtoxin-producing pathogens tolerant to their own phytotoxins. According to the structure based detoxification mechanism of TTR, three site- directed mutants Y141F, D130N and Y141F-D130N were constructed and overexpressed in E. coli. The products were then purified and their properties were analyzed by CD and DLS. The crystal structure of TTR complexed with its natural cofactor, acetyl coenzyme A (AcCoA), to 1.55 Å resolution. The binary complex forms a characteristic “V” shape for substrate binding and contains the four motifs conserved in the GCN5-related N-acetyltransferase (GNAT) superfamily, which also includes the histone acetyltransferases (HATs).
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In 1990, biologists Michael Schlame and Bernd Rustow observed the deacylation of cardiolipin into MLCL, which was then converted back into cardiolipin by a protein using linoleoyl coenzyme A, derived from phosphatidylcholine. However, acyltransferase activities involved in the reacylation of MLCL had not been identified or characterized in any mammalian tissue until 1999, by the Hatch lab at the University of Manitoba, in rat heart mitochondria. In 2003, the same lab purified and characterized an MLCL acyltransferase in pig liver mitochondria, and by comparing this protein against a human protein database, they identified a sequenced but uncharacterized human protein as the enzyme responsible in 2009.
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In this method, an activator binds to an enhancer site and recruits a HAT complex that then acetylates nucleosomal promoter-bound histones by neutralizing the positively charged lysine residues. This charge neutralization causes the histones to have a weaker bond to the negatively charged DNA, which relaxes the chromatin structure, allowing other transcription factors or transcription machinery to bind to the promoter (transcription initiation). Acetylation by HAT complexes may also help keep chromatin open throughout the process of elongation, increasing the speed of transcription. N-terminal acetyltransferase (NAT) transfers the acetyl group from acetyl coenzyme A (Ac-CoA) to the N-terminal amino group of a polypeptide.
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In enzymology, a [acyl-carrier-protein] S-acetyltransferase () is an enzyme that catalyzes the reversible chemical reaction :acetyl-CoA + [acyl-carrier- protein] \rightleftharpoons CoA + acetyl-[acyl-carrier-protein] Thus, the two substrates of this enzyme are acetyl-CoA and acyl carrier protein, whereas its two products are CoA and acetyl-acyl-carrier-protein. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acetyl-CoA:[acyl-carrier-protein] S-acetyltransferase. Other names in common use include acetyl coenzyme A-acyl-carrier-protein transacylase, Acetyl CoA:ACP transacylase, [acyl-carrier-protein]acetyltransferase, [ACP]acetyltransferase, and ACAT.
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All redox reactions take place in the hydrophilic domain of complex I. NADH initially binds to complex I, and transfers two electrons to the flavin mononucleotide (FMN) prosthetic group of the enzyme, creating FMNH2. The electron acceptor – the isoalloxazine ring – of FMN is identical to that of FAD. The electrons are then transferred through the FMN via a series of iron-sulfur (Fe-S) clusters, and finally to coenzyme Q10 (ubiquinone). This electron flow changes the redox state of the protein, inducing conformational changes of the protein which alters the pK values of ionizable side chain, and causes four hydrogen ions to be pumped out of the mitochondrial matrix.
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In enzymology, a rosmarinate synthase () is an enzyme that catalyzes the chemical reaction :caffeoyl-CoA + 3-(3,4-dihydroxyphenyl)lactate \rightleftharpoons CoA + rosmarinate Thus, the two substrates of this enzyme are caffeoyl-CoA and 3-(3,4-dihydroxyphenyl)lactate, whereas its two products are CoA and rosmarinate. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is caffeoyl- CoA:3-(3,4-dihydroxyphenyl)lactate 2'-O-caffeoyl-transferase. Other names in common use include rosmarinic acid synthase, caffeoyl-coenzyme A:3,4-dihydroxyphenyllactic acid, caffeoyltransferase, and 4-coumaroyl- CoA:4-hydroxyphenyllactic acid 4-coumaroyl transferase.
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In enzymology, a glycine C-acetyltransferase () is an enzyme that catalyzes the chemical reaction: :acetyl-CoA + glycine \rightleftharpoons CoA + 2-amino-3-oxobutanoate Thus, the two substrates of this enzyme are acetyl-CoA and glycine, whereas its two products are CoA and 2-amino-3-oxobutanoate. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acetyl-CoA:glycine C-acetyltransferase. Other names in common use include 2-amino-3-ketobutyrate CoA ligase, 2-amino-3-ketobutyrate coenzyme A ligase, 2-amino-3-ketobutyrate- CoA ligase, glycine acetyltransferase, and aminoacetone synthase.
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In enzymology, a 2-oxopropyl-CoM reductase (carboxylating) () is an enzyme that catalyzes the chemical reaction :2-mercaptoethanesulfonate + acetoacetate + NADP+ \rightleftharpoons 2-(2-oxopropylthio)ethanesulfonate + CO2 \+ NADPH The 3 substrates of this enzyme are 2-mercaptoethanesulfonate, acetoacetate, and NADP+, whereas its 3 products are 2-(2-oxopropylthio)ethanesulfonate, CO2, and NADPH. This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is 2-mercaptoethanesulfonate, acetoacetate:NADP+ oxidoreductase (decarboxylating). Other names in common use include NADPH:2-(2-ketopropylthio)ethanesulfonate, oxidoreductase/carboxylase, and NADPH:2-ketopropyl-coenzyme M oxidoreductase/carboxylase.
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In enzymology, a long-chain-fatty-acyl-CoA reductase () is an enzyme that catalyzes the chemical reaction :a long-chain aldehyde + CoA + NADP+ \rightleftharpoons a long-chain acyl-CoA + NADPH + H+ The 3 substrates of this enzyme are long-chain aldehyde, CoA, and NADP+, whereas its 3 products are long-chain acyl-CoA, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is long-chain-aldehyde:NADP+ oxidoreductase (acyl-CoA-forming). Other names in common use include acyl-CoA reductase, and acyl coenzyme A reductase.
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Lovastatin is an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), an enzyme that catalyzes the conversion of HMG- CoA to mevalonate. Mevalonate is a required building block for cholesterol biosynthesis and lovastatin interferes with its production by acting as a reversible competitive inhibitor for HMG-CoA, which binds to the HMG-CoA reductase. Lovastatin is a prodrug, an inactive lactone in its native form, the gamma-lactone closed ring form in which it is administered, is hydrolysed in vivo to the β-hydroxy acid open ring form; which is the active form. Lovastatin and other statins have been studied for their chemopreventive and chemotherapeutic effects.
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If oxygen is present, then following glycolysis, the two pyruvate molecules are brought into the mitochondrion itself to go through the Krebs cycle. In this cycle, the pyruvate molecules from glycolysis are further broken down to harness the remaining energy. Each pyruvate goes through a series of reactions that converts it to acetyl coenzyme A. From here, only the acetyl group participates in the Krebs cycle—in which it goes through a series of redox reactions, catalyzed by enzymes, to further harness the energy from the acetyl group. The energy from the acetyl group, in the form of electrons, is used to reduce NAD+ and FAD to NADH and FADH2, respectively.
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The human NDUFA13 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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Although Nocardia has interesting and important features such as production of antibiotics and aromatic compound-degrading or -converting enzymes, the genetic study of this organism has been hampered by the lack of genetic tools. However, practical Nocardia-E. coli shuttle vectors have been developed recently. The genera Nocardia and Rhodococcus have been found to be closely related, supported by two conserved signature indels consisting of a one- amino-acid deletion in the alpha subunit of acetyl coenzyme A carboxylase (ACC), and a three-amino-acid insertion in a conserved region of an ATP- binding protein that are specifically shared by species from these two genera.
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These genes include carbamate kinase (arcC), shikimate dehydrogenase (aroE), glycerol kinase (glpF), guanylate kinase (gmk), phosphate acetyltransferase (pta), triosephosphate isomerase (tpi) and acetyl coenzyme A acetyltransferase (yqiL) as specified by the MLST website. However, it is not uncommon for up to ten housekeeping genes to be used. For Vibrio vulnificus, the housekeeping genes used are glucose-6-phosphate isomerase (glp), DNA gyrase, subunit B (gyrB), malate-lactate dehydrogenase (mdh), methionyl-tRNA synthetase (metG), phosphoribosylaminoimidazole synthetase (purM), threonine dehyrogenase (dtdS), diaminopimelate decarboxylase (lysA), transhydrogenase alpha subunit (pntA), dihydroorotase (pyrC) and tryptophanase (tnaA). Thus both the number and type of housekeeping genes interrogated by MLST may differ from species to species.
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SDHAF1 is essential for the assembly of the succinate dehydrogenase (SDH) complex (complex II), an enzyme complex that is a component of both the tricarboxylic acid (TCA) cycle and the mitochondrial electron transport chain, and which couples the oxidation of succinate to fumarate with the reduction of ubiquinone (coenzyme Q) to ubiquinol. The succinate dehydrogenase (SDH) complex of the mitochondrial respiratory chain is composed of 4 individual subunits. The protein encoded by the SDHAF1 gene resides in the mitochondria, and is essential for SDH assembly, but does not physically associate with the complex in vivo. Specifically, SDHAF1 mediates and promotes the maturation of the SDHB subunit of the SDH catalytic dimer.
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The trivial name cofactor F430 was assigned in 1978 based on the properties of a yellow sample extracted from Methanobacterium thermoautotrophicum, which had a spectroscopic maximum at 430 nm. It was identified as the MCR cofactor in 1982 and the complete structure was deduced by X-ray crystallography and NMR spectroscopy. Coenzyme F430 features a reduced porphyrin in a macrocyclic ring system called a corphin. In addition, it possesses two additional rings in comparison to the standard tetrapyrrole (rings A-D), having a γ-lactam ring E and a keto-containing carbocyclic ring F. It is the only natural tetrapyrrole containing nickel, an element rarely found in biological systems.
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Epothilone B is a 16-membered polyketide macrolactone with a methylthiazole group connected to the macrocycle by an olefinic bond. The polyketide backbone was synthesized by type I polyketide synthase (PKS) and the thiazole ring was derived from a cysteine incorporated by a nonribosomal peptide synthetase (NRPS). In this biosynthesis, both PKS and NRPS use carrier proteins, which have been post- translationally modified by phosphopantetheine groups, to join the growing chain. PKS uses coenzyme-A thioester to catalyze the reaction and modify the substrates by selectively reducing the β carbonyl to the hydroxyl (Ketoreductase, KR), the alkene (Dehydratase, DH), and the alkane (Enoyl Reductase, ER).
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The human NDUFA11 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The human NDUFA7 gene codes for a subunit of Complex I of the respiratory chain, which transfers electrons from NADH to ubiquinone. Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, which pumps four hydrogen ions out of the mitochondrial matrix.
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The energy required for domain closure comes from the interaction of the enzyme with the substrate. Type II enzymes possess an extra N-terminal beta-sheet domain, and some type II enzymes are allosterically inhibited by NADH. 2-methylcitrate synthase catalyses the conversion of oxaloacetate and propanoyl-CoA into (2R,3S)-2-hydroxybutane-1,2,3-tricarboxylate and coenzyme A. This enzyme is induced during bacterial growth on propionate, while type II hexameric citrate synthase is constitutive. ATP citrate lyase catalyses the Mg.ATP-dependent, CoA-dependent cleavage of citrate into oxaloacetate and acetyl-CoA, a key step in the reductive tricarboxylic acid pathway of CO2 assimilation used by a variety of autotrophic bacteria and archaea to fix carbon dioxide.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post-translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non- histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post-translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post- translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post-translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post-translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post- translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction rely on acetyl- coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post- translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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485 Energy balance, through biosynthetic reactions, can be measured with the following equation: :Energy intake (from food and fluids) = Energy expended (through work and heat generated) + Change in stored energy (body fat and glycogen storage) The first law of thermodynamics states that energy can be neither created nor destroyed. But energy can be converted from one form of energy to another. So, when a calorie of food energy is consumed, one of three particular effects occur within the body: a portion of that calorie may be stored as body fat, triglycerides, or glycogen, transferred to cells and converted to chemical energy in the form of adenosine triphosphate (ATP – a coenzyme) or related compounds, or dissipated as heat.
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NADH:ubiquinone oxidoreductase (complex I) catalyzes the transfer of electrons from NADH to ubiquinone (coenzyme Q) in the first step of the mitochondrial respiratory chain, resulting in the translocation of protons across the mitochondrial inner membrane. The NDUFAF3 gene encodes a mitochondrial complex I assembly protein that localizes to the mitochondrial inner membrane and interacts with complex I subunits and is important for the correct function of the mitochondrial respiratory chain. NDUFAF3 colocalizes, comigrates to several assembly intermediates, and is codependent with NDUFAF4 from the early to late stages of complex I assembly. In addition to their close interactions with each other, NDUFAF3 and NDUFAF4 interact with NDUFS2, NDUFS3, NDUFS8, and NDUFA5 in a translation-dependent early assembly mechanism.
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In enzymology, a methylmalonyl-CoA carboxytransferase () is an enzyme that catalyzes the chemical reaction :(S)-methylmalonyl-CoA + pyruvate \rightleftharpoons propanoyl-CoA + oxaloacetate Thus, the two substrates of this enzyme are (S)-methylmalonyl-CoA and pyruvate, whereas its two products are propanoyl-CoA and oxaloacetate. This enzyme belongs to the family of transferases that transfer one-carbon groups, specifically the carboxy- and carbamoyltransferases. The systematic name of this enzyme class is (S)-methylmalonyl-CoA:pyruvate carboxytransferase. Other names in common use include transcarboxylase, methylmalonyl coenzyme A carboxyltransferase, methylmalonyl-CoA transcarboxylase, oxalacetic transcarboxylase, methylmalonyl-CoA carboxyltransferase, methylmalonyl-CoA carboxyltransferase, (S)-2-methyl-3-oxopropanoyl-CoA:pyruvate carboxyltransferase, (S)-2-methyl-3-oxopropanoyl-CoA:pyruvate carboxytransferase, and carboxytransferase [incorrect].
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This transesterification is catalyzed by an enzyme found in the outer membrane of the mitochondria known as carnitine acyltransferase 1 (also called carnitine palmitoyltransferase 1, CPT1). The fatty acyl–carnitine ester formed then diffuses across the intermembrane space and enters the matrix by facilitated diffusion through carnitine-acylcarnitine translocase (CACT) located on inner mitochondrial membrane. This antiporter return one molecule of carnitine from the matrix to the intermembrane space for every one molecule of fatty acyl–carnitine that moves into the matrix. In the third and final reaction of the carnitine shuttle, the fatty acyl group is transferred from fatty acyl- carnitine to coenzyme A, regenerating fatty acyl–CoA and a free carnitine molecule.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post- translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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This reaction appears to be the only known enzymatic reaction involving the coupling of two molecules with a carbocation. The free electron pair adds to the double bond of IPP, also isomerizing IPP so that the product is an allylic diphosphate. Thus, this part of the isoprenoid pathway appears nearly identical with that of cholesterol with the exception of the insect specific homoisoprenoid units. NAD+-dependent farnesol dehydrogenase, a corpora allata enzyme involved in juvenile hormone synthesis showed that the same source of enzymes efficiently make both mevalonate and its 3-ethyl homolog, homomevalonate. Absolute configuration of homomevalonate and 3-hydroxy-3-ethylglutaryl and 3-hydroxy-3-methylglutaryl coenzyme a, produced by cell-free extracts of insect corpora allata.
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Active site of malate dehydrogenase The active site of malate dehydrogenase is a hydrophobic cavity within the protein complex that has specific binding sites for the substrate and its coenzyme, NAD+. In its active state, MDH undergoes a conformational change that encloses the substrate to minimize solvent exposure and to position key residues in closer proximity to the substrate. The three residues in particular that comprise a catalytic triad are histidine (His-195), aspartate (Asp-168), both of which work together as a proton transfer system, and arginines (Arg-102, Arg-109, Arg-171), which secure the substrate. Mechanistically, malate dehydrogenase catalyzes the oxidation of the hydroxyl group of malate by utilizing NAD+ as an electron acceptor.
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Metmyoglobin is the oxidised form of the oxygen-carrying hemeprotein myoglobin. Metmyoglobin is the cause of the characteristic brown colouration of meat that occurs as it ages. In living muscle, the concentration of metmyoglobin is vanishingly small, due to the presence of the enzyme metmyoglobin reductase, which, in the presence of the cofactor NADH and the coenzyme cytochrome b4 converts the Fe3+ in the heme prosthetic group of metmyoglobin back to the Fe2+ of normal myoglobin. In meat, which is dead muscle, the normal processes of removing metmyoglobin are prevented from effecting this repair, or alternatively the rate of metmyoglobin formation exceeds their capacity, so that there is a net accumulation of metmyoglobin as the meat ages.
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In enzymology, a trans-2-enoyl-CoA reductase (NADPH) () is an enzyme that catalyzes the chemical reaction :trans-2,3-dehydroacyl-CoA + NADPH + H+ \rightleftharpoons acyl-CoA + NADP+ Thus, the three substrates of this enzyme are trans-2,3-dehydroacyl-CoA, NADPH, and H+, whereas its two products are acyl-CoA and NADP+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is acyl-CoA:NADP+ trans-2-oxidoreductase. Other names in common use include NADPH-dependent trans-2-enoyl-CoA reductase, reductase, trans-enoyl coenzyme A, and trans-2-enoyl-CoA reductase (NADPH).
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In this diagram, the hydride acceptor C4 carbon is shown at the top. When the nicotinamide ring lies in the plane of the page with the carboxy-amide to the right, as shown, the hydride donor lies either "above" or "below" the plane of the page. If "above" hydride transfer is class A, if "below" hydride transfer is class B. When bound in the active site of an oxidoreductase, the nicotinamide ring of the coenzyme is positioned so that it can accept a hydride from the other substrate. Depending on the enzyme, the hydride donor is positioned either "above" or "below" the plane of the planar C4 carbon, as defined in the figure.
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In eukaryotes the electrons carried by the NADH that is produced in the cytoplasm are transferred into the mitochondrion (to reduce mitochondrial NAD) by mitochondrial shuttles, such as the malate-aspartate shuttle. The mitochondrial NADH is then oxidized in turn by the electron transport chain, which pumps protons across a membrane and generates ATP through oxidative phosphorylation. These shuttle systems also have the same transport function in chloroplasts. Since both the oxidized and reduced forms of nicotinamide adenine dinucleotide are used in these linked sets of reactions, the cell maintains significant concentrations of both NAD and NADH, with the high NAD/NADH ratio allowing this coenzyme to act as both an oxidizing and a reducing agent.
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Particularly important is the reduction of coenzyme Q in complex III, since a highly reactive free radical is formed as an intermediate (Q·−). This unstable intermediate can lead to electron "leakage", when electrons jump directly to oxygen and form the superoxide anion, instead of moving through the normal series of well-controlled reactions of the electron transport chain. Peroxide is also produced from the oxidation of reduced flavoproteins, such as complex I. However, although these enzymes can produce oxidants, the relative importance of the electron transfer chain to other processes that generate peroxide is unclear. In plants, algae, and cyanobacteria, reactive oxygen species are also produced during photosynthesis, particularly under conditions of high light intensity.
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In enzymology, a deacetylcephalosporin-C acetyltransferase () is an enzyme that catalyzes the chemical reaction :acetyl-CoA + deacetylcephalosporin C \rightleftharpoons CoA + cephalosporin C Thus, the two substrates of this enzyme are acetyl-CoA and deacetylcephalosporin C, whereas its two products are CoA and cephalosporin C. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acetyl- CoA:deacetylcephalosporin-C O-acetyltransferase. Other names in common use include acetyl-CoA:deacetylcephalosporin-C acetyltransferase, DAC acetyltransferase, cefG, deacetylcephalosporin C acetyltransferase, acetyl coenzyme A:DAC acetyltransferase, acetyl-CoA:DAC acetyltransferase, CPC acetylhydrolase, acetyl-CoA:DAC O-acetyltransferase, and DAC-AT. This enzyme participates in penicillin and cephalosporin biosynthesis.
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These are typified by the following two enzymes: 400px Methylmalonyl Coenzyme A mutase (MUT) is an isomerase enzyme which uses the AdoB12 form and reaction type 1 to convert L-methylmalonyl-CoA to succinyl- CoA, an important step in the catabolic breakdown of some amino acids into succinyl-CoA, which then enters energy production via the citric acid cycle. This functionality is lost in vitamin B12 deficiency, and can be measured clinically as an increased serum methylmalonic acid (MMA) concentration. The MUT function is necessary for proper myelin synthesis. Based on animal research, it is thought that the increased methylmalonyl-CoA hydrolyzes to form methylmalonate (methylmalonic acid), a neurotoxic dicarboxylic acid, causing neurological deterioration.
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Hereditary defects in production of the transcobalamins and their receptors may produce functional deficiencies in B12 and infantile megaloblastic anemia, and abnormal B12 related biochemistry, even in some cases with normal blood B12 levels. For the vitamin to serve inside cells, the TC-II/B12 complex must bind to a cell receptor, and be endocytosed. The transcobalamin-II is degraded within a lysosome, and free B12 is finally released into the cytoplasm, where it may be transformed into the proper coenzyme, by certain cellular enzymes (see above). Investigations into the intestinal absorption of B12 point out that the upper limit of absorption per single oral dose, under normal conditions, is about 1.5µg.
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In enzymology, a homocitrate synthase () is an enzyme that catalyzes the chemical reaction :acetyl-CoA + H2O + 2-oxoglutarate \rightleftharpoons (R)-2-hydroxybutane-1,2,4-tricarboxylate + CoA The 3 substrates of this enzyme are acetyl-CoA, H2O, and 2-oxoglutarate, whereas its two products are (R)-2-hydroxybutane-1,2,4-tricarboxylate and CoA. This enzyme belongs to the family of transferases, specifically those acyltransferases that convert acyl groups into alkyl groups on transfer. The systematic name of this enzyme class is acetyl-CoA:2-oxoglutarate C-acetyltransferase (thioester-hydrolysing, carboxymethyl forming). Other names in common use include 2-hydroxybutane-1,2,4-tricarboxylate 2-oxoglutarate-lyase, (CoA-acetylating), acetyl-coenzyme A:2-ketoglutarate C-acetyl transferase, and homocitrate synthetase.
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In enzymology, a diamine N-acetyltransferase () is an enzyme that catalyzes the chemical reaction :acetyl-CoA + an alkane-alpha,omega-diamine \rightleftharpoons CoA + an N-acetyldiamine Thus, the two substrates of this enzyme are acetyl-CoA and alkane-alpha,omega-diamine, whereas its two products are CoA and N-acetyldiamine. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acetyl- CoA:alkane-alpha,omega-diamine N-acetyltransferase. Other names in common use include spermidine acetyltransferase, putrescine acetyltransferase, putrescine (diamine)-acetylating enzyme, diamine acetyltransferase, spermidine/spermine N1-acetyltransferase, spermidine N1-acetyltransferase, acetyl-coenzyme A-1,4-diaminobutane N-acetyltransferase, putrescine acetylase, and putrescine N-acetyltransferase.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post-translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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The field of oxidative phosphorylation began with the report in 1906 by Arthur Harden of a vital role for phosphate in cellular fermentation, but initially only sugar phosphates were known to be involved. However, in the early 1940s, the link between the oxidation of sugars and the generation of ATP was firmly established by Herman Kalckar, confirming the central role of ATP in energy transfer that had been proposed by Fritz Albert Lipmann in 1941. Later, in 1949, Morris Friedkin and Albert L. Lehninger proved that the coenzyme NADH linked metabolic pathways such as the citric acid cycle and the synthesis of ATP. The term oxidative phosphorylation was coined by in 1939.
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Treatment with meldonium therefore shifts the myocardial energy metabolism from fatty acid oxidation to the more favorable oxidation of glucose, or glycolysis, under ischemic conditions. It also reduces the formation of trimethylamine N-oxide (TMAO), a product of carnitine breakdown and implicated in the pathogenesis of atherosclerosis and congestive heart failure. The carnitine shuttle system. (Red: acyl-CoA, Green: carnitine, Red+green: acylcarnitine, CoASH: coenzyme A, CPTI: carnitine palmitoyltransferase I, CPTII: carnitine palmitoyltransferase II, 1: acyl-CoA sintetase, 2: translocase, A: outer mitochondrial membrane, B: Intermembrane space, C: inner mitochondrial membrane, D: mitochondrial matrix) In fatty acid (FA) metabolism, long chain fatty acids in the cytosol cannot cross the mitochondrial membrane because they are negatively charged.
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Each module contains different combinations of the ketoreductase (KR), dehydratase (DH), and enoyl reductase (ER) domains that can modify and tailor the two-carbon subunits to form the resulting fatty acid chain. The final module contains a thioesterase (TE) domain that hydrolyzes the thioester bond to release the fatty acid chain and coenzyme A. Figure 5. Mechanism of synthesis of Callystatin A In the same manner, callystatin A biosynthesis starts with an acetate unit and elongates by either the malonate or the methyl malonate extender units, depending on the specific module. An exception to this is in module 7 where an ethyl malonate molecule replaces the other two options as the extender unit.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post- translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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Common statin- related side effects (headaches, stomach upset, abnormal liver function tests and muscle cramps) were similar to other statins. However, pitavastatin seems to lead to fewer muscle side effects than certain statins that are lipid- soluble, as a result of the fact that pitavastatin is water-soluble (as is pravastatin, for example). One study found that coenzyme Q10 was not reduced as much as with certain other statins (though this is unlikely given the inherent chemistry of the HMG-CoA reductase pathway that all statin drugs inhibit). As opposed to other statins, there is evidence that pitavastatin improves insulin resistance in humans, with insulin resistance assessed by the homeostatic model assessment (HOMA-IR) method.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post-translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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This lack of nucleotide recycling is detrimental since the mitochondria cannot synthesize entirely new deoxynucleotides, and the inner membrane of the mitochondria prevents the negatively charged nucleotides of the cytosol from entering. The SUCLA2 gene codes for the beta- subunit of SCS-A. This enzyme catalyzes the synthesis of succinate and coenzyme A into succinyl-CoA, but is also associated with the complex formed by nucleoside diphosphate kinase (NDPK) in the last step of the dNTP salvage pathway. The RRM2B gene, which is expressed in the cell nucleus, codes for one of two versions of the R2 subunit of ribonucleotide reductase, which generates nucleotide precursors required for DNA replication by reducing ribonucleoside diphosphates to deoxyribonucleoside diphosphates.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl- coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post- translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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The NDUFAF7 gene encodes an assembly factor protein that is localized in the mitochondria and which helps in the assembly and stabilization of complex I, a large multi- subunit enzyme in the mitochondrial respiratory chain. NADH:ubiquinone oxidoreductase (complex I) is involved in several physiological activities in the cell, including metabolite transport and ATP synthesis. Complex I catalyzes the transfer of electrons from NADH to ubiquinone (coenzyme Q) in the first step of the mitochondrial respiratory chain, resulting in the translocation of protons across the inner mitochondrial membrane. The encoded protein of NDUFAF7 is a methyltransferase that symmetrically dimethylates the ω-NG,NG′ atoms of Arg85 of subunit NDUFS2 of complex I in the early stages of its assembly.
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Lysine acetylation Proteins are typically acetylated on lysine residues and this reaction relies on acetyl-coenzyme A as the acetyl group donor. In histone acetylation and deacetylation, histone proteins are acetylated and deacetylated on lysine residues in the N-terminal tail as part of gene regulation. Typically, these reactions are catalyzed by enzymes with histone acetyltransferase (HAT) or histone deacetylase (HDAC) activity, although HATs and HDACs can modify the acetylation status of non-histone proteins as well. The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post-translational regulatory mechanism These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.
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Pyruvate dehydrogenase complex reaction Pyruvate decarboxylation or pyruvate oxidation, also known as the link reaction, is the conversion of pyruvate into acetyl-CoA by the enzyme complex pyruvate dehydrogenase complex. The reaction may be simplified as: 1 Pyruvate + 1 NAD+ \+ CoA → 1 Acetyl-CoA + NADH + CO2 \+ H+ Pyruvate oxidation is the step that connects glycolysis and the Krebs cycle. In glycolysis, a single glucose molecule (6 carbons) is split into 2 pyruvates (3 carbons each), hence link reaction occurs twice for each glucose molecule to produce a total of 2 acetyl-CoA molecules, which can then enter the Krebs cycle. Energy-generating ions and molecules such as amino acids and carbohydrates enter the Krebs cycle as acetyl coenzyme A and oxidize in the cycle.
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Citrate synthase enzymes are found in two distinct structural types: type I enzymes (found in eukaryotes, Gram-positive bacteria and archaea) form homodimers and have shorter sequences than type II enzymes, which are found in Gram-negative bacteria and are hexameric in structure. In both types, the monomer is composed of two domains: a large alpha-helical domain consisting of two structural repeats, where the second repeat is interrupted by a small alpha-helical domain. The cleft between these domains forms the active site, where both citrate and acetyl-coenzyme A bind. The enzyme undergoes a conformational change upon binding of the oxaloacetate ligand, whereby the active site cleft closes over in order to form the acetyl- CoA binding site.
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Enzymatic activity of HADHB in beta-oxidation This gene encodes the beta subunit of the mitochondrial trifunctional protein, a catalyst of mitochondrial beta-oxidation of long chain fatty acids. The HADHB protein catalyzes the final step of beta- oxidation, in which 3-ketoacyl CoA is cleaved by the thiol group of another molecule of Coenzyme A. The thiol is inserted between C-2 and C-3, which yields an acetyl CoA molecule and an acyl CoA molecule, which is two carbons shorter. The encoded protein can also bind RNA and decreases the stability of some mRNAs. The genes of the alpha and beta subunits of the mitochondrial trifunctional protein are located adjacent to each other in the human genome in a head-to-head orientation.
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Fatty acids bound to coenzyme A allow penetration into mitochondria. Once inside the mitochondrion, the bound fatty acids are used as fuel in cells predominantly through beta oxidation, which cleaves two carbons from the acyl-CoA molecule in every cycle to form acetyl-CoA. Acetyl-CoA enters the citric acid cycle, where it undergoes an aldol condensation with oxaloacetate to form citric acid; citric acid then enters the tricarboxylic acid cycle (TCA), which harvests a very high energy yield per carbon in the original fatty acid. Biochemical pathway of ketone synthesis in the liver and utilization by organs Acetyl-CoA can be metabolized through the TCA cycle in any cell, but it can also undergo ketogenesis in the mitochondria of liver cells.
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Aramchol inhibits the activity of stearoyl coenzyme A desaturase 1 (SCD1) in the liver. This is likely a direct effect since the mRNA of this and other lipogenic genes or the activities of nuclear receptors are not affected. The physiologic effects of SCD1 inhibition are: decreased synthesis of fatty acids, resulting in a decrease in storage triglycerides and other esters of fatty acids. This reduces liver fat (including triglycerides and free fatty acids), and results in an improvement in insulin resistance. Aramchol’s mechanism of action, inhibition of the SCD1 enzyme, has been confirmed in human liver microsomes2 and in animal studies by showing a reduction of the SCD1 activity marker, the fatty acid ratio 16:1/16:0, following Aramchol treatment.
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Barker was hired in 1936 by the University of California, Berkeley to teach soil microbiology. He was part of a team that developed the use of Carbon-14 as a radioactive tracer, using the technique in 1944 to show how sucrose is synthesized in living cells by enzymes. Research led by Barker during the 1950s provided insights into the uses of vitamin B12 in the body using bacterium he had isolated from mud taken from San Francisco Bay. By 1959, through documenting the metabolic flow of the vitamin B12 coenzyme, Barker was able to show its role in the body, helping to explain various diseases, such as pernicious anemia, one of a series of conditions resulting from vitamin B12 deficiency.
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There are various types of phospholipids; consequently, their synthesis pathways differ. However, the first step in phospholipid synthesis involves the formation of phosphatidate or diacylglycerol 3-phosphate at the endoplasmic reticulum and outer mitochondrial membrane. The synthesis pathway is found below: Phosphatidic acid synthesis The pathway starts with glycerol 3-phosphate, which gets converted to lysophosphatidate via the addition of a fatty acid chain provided by acyl coenzyme A. Then, lysophosphatidate is converted to phosphatidate via the addition of another fatty acid chain contributed by a second acyl CoA; all of these steps are catalyzed by the glycerol phosphate acyltransferase enzyme. Phospholipid synthesis continues in the endoplasmic reticulum, and the biosynthesis pathway diverges depending on the components of the particular phospholipid.
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Nathan Oram Kaplan (June 25, 1917 – April 15, 1986) was an American biochemist who studied enzymology and chemotherapy. After completing a B.A. in chemistry at UCLA in 1939, Kaplan studied carbohydrate metabolism in the liver under David M. Greenberg at the University of California, Berkeley medical school. He earned his Ph.D. in 1943. From 1942 to 1944, Kaplan participated in the Manhattan Project, and then spent a year as an instructor at Wayne State University. From 1945 to 1949, Kaplan worked with Fritz Lipmann at Massachusetts General Hospital to study coenzyme A. Kaplan went to the University of Illinois College of Medicine as an assistant professor in 1949, and from 1950 to 1957 he worked at the McCollum-Pratt Institute of Johns Hopkins University.
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Rossmann fold in part of the lactate dehydrogenase of Cryptosporidium parvum, showing NAD in red, beta sheets in yellow, and alpha helices in purple. Nicotinamide adenine dinucleotide has several essential roles in metabolism. It acts as a coenzyme in redox reactions, as a donor of ADP-ribose moieties in ADP-ribosylation reactions, as a precursor of the second messenger molecule cyclic ADP-ribose, as well as acting as a substrate for bacterial DNA ligases and a group of enzymes called sirtuins that use NAD to remove acetyl groups from proteins. In addition to these metabolic functions, NAD+ emerges as an adenine nucleotide that can be released from cells spontaneously and by regulated mechanisms, and can therefore have important extracellular roles.
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In enzymology, a propionyl-CoA C2-trimethyltridecanoyltransferase () is an enzyme that catalyzes the chemical reaction :4,8,12-trimethyltridecanoyl-CoA + propanoyl-CoA \rightleftharpoons 3-oxopristanoyl-CoA + CoA Thus, the two substrates of this enzyme are 4,8,12-trimethyltridecanoyl-CoA and propanoyl- CoA, whereas its two products are 3-oxopristanoyl-CoA and CoA. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is 4,8,12-trimethyltridecanoyl-CoA:propanoyl-CoA C2-4,8,12-trimethyltridecanoyltransferase. Other names in common use include 3-oxopristanoyl-CoA hydrolase, 3-oxopristanoyl-CoA thiolase, peroxisome sterol carrier protein thiolase, sterol carrier protein, oxopristanoyl-CoA thiolase, peroxisomal 3-oxoacyl coenzyme A thiolase, SCPx, 4,8,12-trimethyltridecanoyl- CoA:propanoyl-CoA, and 2-C-4,8,12-trimethyltridecanoyltransferase.
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NADH:ubiquinone oxidoreductase (complex I) catalyzes the transfer of electrons from NADH to ubiquinone (coenzyme Q) in the first step of the mitochondrial respiratory chain, resulting in the translocation of protons across the inner mitochondrial membrane. NDUFAF4 encodes a complex I assembly factor that is important for the correct assembly and function of complex I. NDUFAF4 colocalizes, comigrates to several assembly intermediates, and is codependent with NDUFAF3 from the early to late stages of complex I assembly. In addition to their close interactions with each other, NDUFAF4 and NDUFAF3 interact with NDUFS2, NDUFS3, NDUFS8, and NDUFA5 in a translation-dependent early assembly mechanism. NDUFAF4 has also been shown to play a role in growth and apoptosis regulation through a CaM-mediated mechanism involving MMP-9 secretion.
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Acyl-CoA-binding protein in humans belongs to the family of Acyl-CoA-binding proteins. This gene encodes diazepam binding inhibitor, a protein that is regulated by hormones and is involved in lipid metabolism and the displacement of beta-carbolines and benzodiazepines, which modulate signal transduction at type A gamma-aminobutyric acid receptors located in brain synapses. The protein is conserved from yeast to mammals, with the most highly conserved domain consisting of seven contiguous residues that constitute the hydrophobic binding site for medium- and long-chain acyl-Coenzyme A esters. Diazepam binding inhibitor also mediates the feedback regulation of pancreatic secretion and the postprandial release of cholecystokinin, in addition to its role as a mediator in corticotropin-dependent synthesis of steroids in the adrenal gland.
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Disulfiram is used as a second line treatment, behind acamprosate and naltrexone, for alcohol dependence. Under normal metabolism, alcohol is broken down in the liver by the enzyme alcohol dehydrogenase to acetaldehyde, which is then converted by the enzyme acetaldehyde dehydrogenase to a harmless acetic acid derivative (acetyl coenzyme A). Disulfiram blocks this reaction at the intermediate stage by blocking acetaldehyde dehydrogenase. After alcohol intake under the influence of disulfiram, the concentration of acetaldehyde in the blood may be five to 10 times higher than that found during metabolism of the same amount of alcohol alone. As acetaldehyde is one of the major causes of the symptoms of a "hangover", this produces immediate and severe negative reaction to alcohol intake.
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Her work with Lipmann and Leonard Spector included the novel demonstration of ATP being involved in a reaction to activate Coenzyme A and produce pyrophosphate, and the discovery of carbamoyl phosphate, a key component of nucleotides which are essential to energy transfer within cells. By the time Jones joined Brandeis as a faculty member, she had published 13 papers: two from when she was a technician at Armour, two more from her graduate work at Yale, plus another nine papers from her work in the Lipmann laboratory. She continued her prolific work at Brandeis while collaborating with Leonard Spector. The two continued to work on carbamoyl phosphate, identifying carbon dioxide or bicarbonate as the source for the initial activation step for carbamoyl phosphate formation.
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The Wood–Ljungdahl pathway consists of two different reactions that break down carbon dioxide. The first pathway involves CODH converting carbon dioxide into carbon monoxide through a two-electron transfer, and the second reaction involves ACS synthesizing acetyl-CoA using the carbon monoxide from CODH together with coenzyme-A (CoA) and a methyl group from a corrinoid-iron sulfur protein, CFeSP. The two main overall reactions are as follows: The Acetyl-CoA produced can be used in a variety of ways depending on the needs of the organism. For example, acetate-forming bacteria use acetyl-CoA for their autotrophic growth processes, and methanogenic archae such as Methanocarcina barkeri convert the acetyl-CoA into acetate and use it as an alternative source of carbon instead of CO. Anaerobic oxidation in organisms via Wood–Ljungdahl Pathway.
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Insig deficiency in mice caused a marked buildup of cholesterol precursors in skin associated with a marked increase in 3-hydroxy-3-methylglutaryl coenzyme A reductase protein and hair and skin defects corrected by topical simvastatin, an inhibitor of reductase. REV- ERBalpha participates in the circadian modulation of sterol regulatory element-binding protein (SREBP) activity, and thereby in the daily expression of SREBP target genes involved in cholesterol and lipid metabolism. This control is exerted via the cyclic transcription of Insig2, encoding a trans- membrane protein that sequesters SREBP proteins to the endoplasmic reticulum membranes and thereby interferes with the proteolytic activation of SREBPs in Golgi membranes. REV-ERBalpha also participates in the cyclic expression of cholesterol-7alpha-hydroxylase (CYP7A1), the rate-limiting enzyme in converting cholesterol to bile acids.
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In enzymology, a 3alpha,7alpha-dihydroxy-5beta-cholestanate-CoA ligase () is an enzyme that catalyzes the chemical reaction :ATP + (25R)-3alpha,7alpha- dihydroxy-5beta-cholestan-26-oate + CoA \rightleftharpoons AMP + diphosphate + (25R)-3alpha,7alpha-dihydroxy-5beta-cholestanoyl-CoA The 3 substrates of this enzyme are ATP, (25R)-3alpha,7alpha-dihydroxy-5beta-cholestan-26-oate, and CoA, whereas its 3 products are AMP, diphosphate, and (25R)-3alpha,7alpha- dihydroxy-5beta-cholestanoyl-CoA. This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The systematic name of this enzyme class is (25R)-3alpha,7alpha- dihydroxy-5beta-cholestan-26-oate:CoA ligase (AMP-forming). Other names in common use include 3alpha,7alpha-dihydroxy-5beta-cholestanoyl coenzyme A synthetase, DHCA-CoA ligase, and 3alpha,7alpha-dihydroxy-5beta- cholestanate:CoA ligase (AMP-forming).
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Oxalyl-CoA decarboxylase is hypothesized to be evolutionarily related to acetolactate synthase, a TPP-dependent enzyme responsible for the biosynthesis of branched chain amino acids in certain organisms. Sequence alignments between the two enzymes support this claim, as do the presence of vestigial FAD-binding pockets that play no role in either enzyme’s catalytic activity. The binding of FAD at this site in acetolactate synthase and the binding of ADP at a cognate site in OXC are thought to play roles in the stabilization of the tertiary structures of the proteins. No FAD binding is observed in oxalyl-CoA decarboxylase, but an excess of coenzyme A in the crystal structure has led to the hypothesis that the binding site was co-opted during OXC evolution to bind the CoA moiety of its substrate.
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Metabolically, Thermococcus spp. have developed a different form of glycolysis from eukaryotes and prokaryotes. One example of a metabolic pathway for these organisms is the metabolism of peptides, which occurs in three steps: first, hydrolysis of the peptides to amino acids is catalyzed by peptidases, then the conversion of the amino acids to keto acids is catalyzed by aminotransferases, and finally CO2 is released from the oxidative decarboxylation or the keto acids by four different enzymes, which produces coenzyme A derivatives that are used in other important metabolic pathways. Thermococcus species also have the enzyme rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase), which is made from enzymes involved in the metabolism of nucleic acids in Thermococcus kodakarensis, showing how integrated these metabolic systems truly are for these hyperthermophilic microorganisms.
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Hastings, J.W., McElroy, W.D. and Coulombre, J. (1953) In other work when he was in the McElroy lab he examined the basic biochemical mechanism of firefly luciferase and demonstrated that coenzyme A stimulates light emission.McElroy, W.D., Hastings, J.W., Sonnenfeld, V. and Coulombre, J. (1953) His lab first demonstrated that the green in vivo coelenterate bioluminescence occurs because of energy transfer from the luminescent molecule (aequorin), which alone emits blue light, to a secondary green emitter which they termed green fluorescent protein (GFP). Once characterized and cloned, GFP has become a crucial molecule used as a reporter and tagging tool for studying gene activation and developmental patterns. Osamu Shimomura, Martin Chalfie and Roger Tsien received the Nobel Prize in Chemistry in 2008 for their work on this remarkable molecule.
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This provides information on the relevant enzymes and details the relationship with several other metabolic processes: glycine, serine, and threonine metabolism which provides hydroxypyruvate and glyoxylate, purine metabolism which provides glyoxylate, pyruvate metabolism which provides (S)-malate and formate, carbon fixation which consumes 3-phospho-D-glycerate and provides D-ribulose 1,5-P2, ascorbate and aldarate metabolism which shares tartronate-semialdehyde, nitrogen metabolism which shares formate, pyruvate metabolism and the citrate cycle which share oxaloacetate, and vitamin B6 metabolism which consumes glycolaldehyde. The glyoxylate cycle describes an important subset of these reactions involved in biosynthesis of carbohydrates from fatty acids or two-carbon precursors which enter the system as acetyl- coenzyme A. Its crucial enzymes are isocitrate lyase and malate synthase. However, alternate pathways have been proposed in organisms lacking isocitrate lyase.
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DNA uses the deoxynucleotides C, G, A, and T, while RNA uses the ribonucleotides (which have an extra hydroxyl(OH) group on the pentose ring) C, G, A, and U. Modified bases are fairly common (such as with methyl groups on the base ring), as found in ribosomal RNA or transfer RNAs or for discriminating the new from old strands of DNA after replication. Each nucleotide is made of an acyclic nitrogenous base, a pentose and one to three phosphate groups. They contain carbon, nitrogen, oxygen, hydrogen and phosphorus. They serve as sources of chemical energy (adenosine triphosphate and guanosine triphosphate), participate in cellular signaling (cyclic guanosine monophosphate and cyclic adenosine monophosphate), and are incorporated into important cofactors of enzymatic reactions (coenzyme A, flavin adenine dinucleotide, flavin mononucleotide, and nicotinamide adenine dinucleotide phosphate).
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In enzymology, a 1-acylglycerophosphocholine O-acyltransferase () is an enzyme that catalyzes the chemical reaction :acyl-CoA + 1-acyl-sn- glycero-3-phosphocholine \rightleftharpoons CoA + 1,2-diacyl-sn- glycero-3-phosphocholine Thus, the two substrates of this enzyme are acyl-CoA and 1-acyl-sn-glycero-3-phosphocholine, whereas its two products are CoA and 1,2-diacyl-sn-glycero-3-phosphocholine. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is acyl- CoA:1-acyl-sn-glycero-3-phosphocholine O-acyltransferase. Other names in common use include lysolecithin acyltransferase, 1-acyl-sn- glycero-3-phosphocholine acyltransferase, acyl coenzyme A-monoacylphosphatidylcholine acyltransferase, acyl-CoA:1-acyl- glycero-3-phosphocholine transacylase, lysophosphatide acyltransferase, and lysophosphatidylcholine acyltransferase.
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Alpha-methylacyl-CoA racemase (AMACR) is an enzyme that in humans is encoded by the AMACR gene. AMACR catalyzes the following chemical reaction: :(2R)-2-methylacyl-CoA \rightleftharpoons (2S)-2-methylacyl-CoA In mammalian cells, the enzyme is responsible for converting (2R)-methylacyl-CoA esters to their (2S)-methylacyl-CoA epimers and known substrates, including coenzyme A esters of pristanic acid (mostly derived from phytanic acid, a 3-methyl branched-chain fatty acid that is abundant in the diet) and bile acids derived from cholesterol. This transformation is required in order to degrade (2R)-methylacyl-CoA esters by β-oxidation, which process requires the (2S)-epimer. The enzyme is known to be localised in peroxisomes and mitochondria, both of which are known to β-oxidize 2-methylacyl-CoA esters.
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Early insights into the mechanism of the catalytic reaction mainly focused on isotopic methods. Both pathways of lysine degradation and the role of 5,6-LAM were discovered in early work by Stadtman's group during 1950s-1960s. In 1971, having a tritiated α-lysine, 2,5-diaminohexanoate, and coenzyme in hand, Colin Morley and T. Stadtman discovered the role of 5'-deoxyadenosylcobalamin (AdoCbl) as a source for hydrogen migration. Recently, much progress has been made toward detecting the intermediates of the reaction, especially towards I•. Based on quantum-mechanical calculations, it was proposed that with 5-fluorolysine as a substitute for D-lysine the 5-FS• species can be captured and analyzed. A similar approach was applied towards PLP modification, when it was modified to 4’-cyanoPLP or PLP-NO.
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Arrow pushing mechanism for the reaction catalyzed by lactate dehydrogenase LDH in humans uses His(193) as the proton donor, and works in unison with the coenzyme (Arg99 and Asn138), and substrate (Arg106; Arg169; Thr248) binding residues. The His(193) active site, is not only found in the human form of LDH, but is found in many different animals, showing the convergent evolution of LDH. The two different subunits of LDH (LDHA, also known as the M subunit of LDH, and LDHB, also known as the H subunit of LDH) both retain the same active site and the same amino acids participating in the reaction. The noticeable difference between the two subunits that make up LDH's tertiary structure is the replacement of alanine (in the M chain) with a glutamine (in the H chain).
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HMG-CoA reductase (3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, officially abbreviated HMGCR) is the rate-controlling enzyme (NADH-dependent, ; NADPH-dependent, ) of the mevalonate pathway, the metabolic pathway that produces cholesterol and other isoprenoids. Normally in mammalian cells this enzyme is suppressed by cholesterol derived from the internalization and degradation of low density lipoprotein (LDL) via the LDL receptor as well as oxidized species of cholesterol. Competitive inhibitors of the reductase induce the expression of LDL receptors in the liver, which in turn increases the catabolism of plasma LDL and lowers the plasma concentration of cholesterol, which is considered, by those who accept the standard lipid hypothesis, an important determinant of atherosclerosis. This enzyme is thus the target of the widely available cholesterol-lowering drugs known collectively as the statins.
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In enzymology, a (R)-2-hydroxyacid dehydrogenase () is an enzyme that catalyzes the chemical reaction :(2R)-3-sulfolactate + NAD(P) \rightleftharpoons 3-sulfopyruvate + NAD(P)H + H The 3 substrates of this enzyme are (2R)-3-sulfolactic acid, NAD, and NADP, whereas its 4 products are 3-sulfopyruvic acid, NADH, NADPH, and H. This enzyme is important in the metabolism of archaea, particularly their biosynthesis of coenzymes such as coenzyme M, tetrahydromethanopterin and methanofuran. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD or NADP as acceptor. The systematic name of this enzyme class is (R)-2-hydroxyacid:NAD(P) oxidoreductase. Other names in common use include (R)-sulfolactate:NAD(P) oxidoreductase, L-sulfolactate dehydrogenase, ComC, and (R)-sulfolactate dehydrogenase.
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7,8-didemethyl-8-hydroxy-5-deazariboflavin synthase (, FO synthase) and 5-amino-6-(D-ribitylamino)uracil—L-tyrosine 4-hydroxyphenyl transferase () are two enzymes always complexed together to achieve synthesis of FO, a precursor to Coenzyme F420. Their systematic names are 5-amino-5-(4-hydroxybenzyl)-6-(D-ribitylimino)-5,6-dihydrouracil ammonia-lyase (7,8-didemethyl-8-hydroxy-5-deazariboflavin-forming) and 5-amino-6-(D-ribitylamino)uracil:L-tyrosine, 4-hydroxyphenyl transferase respectively. The enzymes catalyse the following chemical reactions: : (2.5.1.147) 5-amino-6-(D-ribitylamino)uracil + L-tyrosine + S-adenosyl-L- methionine = 5-amino-5-(4-hydroxybenzyl)-6-(D-ribitylimino)-5,6-dihydrouracil + 2-iminoacetate + L-methionine + 5'-deoxyadenosin : (4.3.1.32) 5-amino-5-(4-hydroxybenzyl)-6-(D-ribitylimino)-5,6-dihydrouracil + S-adenosyl- L-methionine = 7,8-didemethyl-8-hydroxy-5-deazariboflavin + NH3 \+ L-methionine + 5'-deoxyadenosine Enzyme 2.5.
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Before fatty acids can undergo degradation to fulfill the metabolic needs of an organism, they must first be activated via a thioester linkage to coenzyme A. This process is catalyzed by the enzyme acyl CoA synthetase, and occurs on the outer mitochondrial membrane. This activation is accomplished in two reactive steps: (1) the fatty acid reacts with a molecule of ATP to form an enzyme-bound acyl adenylate and pyrophosphate (PPi), and (2) the sulfhydryl group of CoA attacks the acyl adenylate, forming acyl CoA and a molecule of AMP. Each of these two steps is reversible under biological conditions, save for the additional hydrolysis of PPi by inorganic pyrophosphatase. This coupled hydrolysis provides the driving force for the overall forward activation reaction, and serves as a source of inorganic phosphate used in other biological processes.
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Organocatalytic transfer hydrogenation has been described by the group of List in 2004 in a system with a Hantzsch ester as hydride donor and an amine catalyst: Organocatalytic Transfer Hydrogenation Yang 2004 In this particular reaction the substrate is an α,β-unsaturated carbonyl compound. The proton donor is oxidized to the pyridine form and resembles the biochemically relevant coenzyme NADH. In the catalytic cycle for this reaction the amine and the aldehyde first form an iminium ion, then proton transfer is followed by hydrolysis of the iminium bond regenerating the catalyst. By adopting a chiral imidazolidinone MacMillan organocatalyst an enantioselectivity of 81% ee was obtained: :Asymmetric Organocatalytic Transfer Hydrogenation Yang 2004 :MacMillan Asymmetric Organocatalytic Transfer Hydrogenation In a case of stereoconvergence, both the E-isomer and the Z-isomer in this reaction yield the (S)-enantiomer.
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This protein is a Long-chain-fatty-acid—CoA ligase that plays a major role in fatty acid metabolism (particularly in the brain) by charging fatty acids with Coenzyme A to form acyl-CoA. This function can not only alter fatty acid metabolism but also modulate the function of protein kinase Cs and nuclear thyroid hormone receptor. The gene is located on human chromosome 5 at position q31.1. Chromosome translocations between ETV6 and ACSL6 at different chromosome break points create various t(5:12)(q31;p13) ETV6-ACSL6 fusion genes encoding ETV6-ACSL6 fusion proteins. The functionality of ETV6-ACSL6 fusion proteins and the mechanism by which they promote clonal hypereosinophil may, based on indirect evidence in 5 case studies, relate to a loss or gain in function of the ETV6 portion of the fusion protein.
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The groups findings were published the titles: Evidence Reports/Technology Assessments, No. 83.Evidence Reports/Technology Assessments She also reported a study that revealed that Vitex may affect levels of hormones that influence the menstrual cycle, reducing the symptoms of PMS.Articles Library She was Associate Director, Botanical Research Center, Center for Human Nutrition, UCLA (2004)Council for Responsible Nutrition - November 2004 Cordero Hardy was named medical director of the Cedars-Sinai Integrative Medicine Medical Group in Los Angeles. She was the Project Director of the program which studied the effect of supplemental antioxidants Vitamin C, Vitamin E, and Coenzyme Q10 for the prevention and treatment of cardiovascular disease. The groups findings were published the titles: Evidence Reports/Technology Assessments, No. 83. In 2004 she was also the Associate Director of the Botanical Research Center, Center for Human Nutrition in UCLA.
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There are three energy-transducing enzymes in the electron transport chain - NADH:ubiquinone oxidoreductase (complex I), Coenzyme Q – cytochrome c reductase (complex III), and cytochrome c oxidase (complex IV). Complex I is the largest and most complicated enzyme of the electron transport chain. The reaction catalyzed by complex I is: :NADH + H+ \+ CoQ + 4H+in→ NAD+ \+ CoQH2 \+ 4H+out In this process, the complex translocates four protons across the inner membrane per molecule of oxidized NADH, helping to build the electrochemical potential difference used to produce ATP. Escherichia coli complex I (NADH dehydrogenase) is capable of proton translocation in the same direction to the established Δψ, showing that in the tested conditions, the coupling ion is H+. Na+ transport in the opposite direction was observed, and although Na+ was not necessary for the catalytic or proton transport activities, its presence increased the latter.
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Cholesterol is biosynthesized in a series of more than 25 separate enzymatic reactions that initially involves three successive condensations of acetyl-CoA units to form the six-carbon compound 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA). This is reduced to mevalonate and then converted in a series of reactions to the isoprenes that are building-blocks of squalene, the immediate precursor to sterols, which cyclizes to lanosterol (a methylated sterol) and further metabolized to cholesterol. A number of early attempts to block the synthesis of cholesterol resulted in agents that inhibited late in the biosynthetic pathway between lanosterol and cholesterol. A major rate-limiting step in the pathway is at the level of the microsomal enzyme that catalyzes the conversion of HMG CoA to mevalonic acid, and that has been considered to be a prime target for pharmacologic intervention for several years.
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Acyl-CoA dehydrogenases (ACADs) are a class of enzymes that function to catalyze the initial step in each cycle of fatty acid β-oxidation in the mitochondria of cells. Their action results in the introduction of a trans double-bond between C2 (α) and C3 (β) of the acyl-CoA thioester substrate Flavin adenine dinucleotide (FAD) is a required co-factor in addition to the presence of an active site glutamate in order for the enzyme to function. The following reaction is the oxidation of the fatty acid by FAD to afford an α,β-unsaturated fatty acid thioester of Coenzyme A: center ACADs can be categorized into three distinct groups based on their specificity for short-, medium-, or long-chain fatty acid acyl-CoA substrates. While different dehydrogenases target fatty acids of varying chain length, all types of ACADs are mechanistically similar.
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Agents currently under investigation as neuroprotective agents include anti-apoptotic drugs (omigapil, CEP-1347), antiglutamatergic agents, monoamine oxidase inhibitors (selegiline, rasagiline), promitochondrial drugs (coenzyme Q10, creatine), calcium channel blockers (isradipine) and growth factors (GDNF). Researchers are also investigating vaccines for Parkinson's disease that produce cells that change the way the body's immune system responds to the loss of dopamine. This treatment has shown success in reversing Parkinson's in mice, and researchers are investigating the viability of clinical studies in people. Exercise may be neuroprotective. Animal studies show exercise may protect against dopaminergic neurotoxins, and research conducted via prospective studies shows the risk of Parkinson’s disease in humans is reduced significantly by midlife exercise. More research is needed to investigate the benefits of exercise in the early stage of Parkinson’s, the most suitable type of exercise, when exercise should be implemented, and the optimal duration of exercises.
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Authors: Rod Greenshields; Anthony Rimmington; Harry Rothman. Technology Analysis & Strategic Management, Volume 2, Issue 1 1990 , pages 63 - 76. Quote: "There arc large n-paraffins- based SCP factories at various stages of construction at Angarsk, Kirishi (1 00,000 tonnes/year), Kremenchug (120,000 tonnes), Kstovo, Mozyr (300,000 tonnes), Novopolotsk (100,000 tonnes), Svetloyar (240,000 tonnes projected), arid Syzran... " The facility also produced certain pharmaceutical products, such as Coenzyme Q10 (Ubiquinone-10), which is used as a dietary supplement.. Abstract: "The use of synthetic ubiquinone-10 (2 and 10 mg/kg) as a therapeutic food additive normalized the counts of erythrocytes, reticulocytes, and leukocytes and the content of hemoglobin in the blood and inhibited lipid peroxidation in erythrocytes in irradiated rats (3 Gy)." Quote: "...ubiquinone-10 synthesized at the BVK Plant (Kstovo)..." Belgium's SolVin is working with SIBUR on building a PVC production plant "RusVinyl" in Kstovsky District.
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Scientists in academic settings and the pharmaceutical industry began trying to develop a drug to reduce cholesterol more effectively. There were several potential targets, with 30 steps in the synthesis of cholesterol from acetyl- coenzyme A. In 1971, Akira Endo, a Japanese biochemist working for the pharmaceutical company Sankyo, began to investigate this problem. Research had already shown cholesterol is mostly manufactured by the body in the liver with the enzyme HMG-CoA reductase. Endo and his team reasoned that certain microorganisms may produce inhibitors of the enzyme to defend themselves against other organisms, as mevalonate is a precursor of many substances required by organisms for the maintenance of their cell walls or cytoskeleton (isoprenoids). The first agent they identified was mevastatin (ML-236B), a molecule produced by the fungus Penicillium citrinum. A British group isolated the same compound from Penicillium brevicompactum, named it compactin, and published their report in 1976.
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Monoamine oxidase B has a hydrophobic bipartite elongated cavity that (for the "open" conformation) occupies a combined volume close to 700 Å3. hMAO-A has a single cavity that exhibits a rounder shape and is larger in volume than the "substrate cavity" of hMAO-B. The first cavity of hMAO-B has been termed the entrance cavity (290 Å3), the second substrate cavity or active site cavity (~390 Å3) – between both an isoleucine199 side- chain serves as a gate. Depending on the substrate or bound inhibitor, it can exist in either an open or a closed form, which has been shown to be important in defining the inhibitor specificity of hMAO B. At the end of the substrate cavity is the FAD coenzyme with sites for favorable amine binding about the flavin involving two nearly parallel tyrosyl (398 and 435) residues that form what has been termed an aromatic cage.
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Complex I is a giant enzyme with the mammalian complex I having 46 subunits and a molecular mass of about 1,000 kilodaltons (kDa). The structure is known in detail only from a bacterium; in most organisms the complex resembles a boot with a large "ball" poking out from the membrane into the mitochondrion. The genes that encode the individual proteins are contained in both the cell nucleus and the mitochondrial genome, as is the case for many enzymes present in the mitochondrion. The reaction that is catalyzed by this enzyme is the two electron oxidation of NADH by coenzyme Q10 or ubiquinone (represented as Q in the equation below), a lipid-soluble quinone that is found in the mitochondrion membrane: The start of the reaction, and indeed of the entire electron chain, is the binding of a NADH molecule to complex I and the donation of two electrons.
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The TTC19 gene encodes for one of the ten nuclear proteins essential for the assembly and function of the Ubiquinol Cytochrome c Reductase or Complex III of the mitochondrial respiratory chain. The Ubiquinol Cytochrome c Reductase is responsible for catalyzing the transfer of electrons from coenzyme Q to cytochrome c as well as pumping protons from the matrix into the inner membrane which results in the generation of an ATP-coupled electrochemical potential. The TTC19 subunit is necessary for the preservation of the structural and functional integrity of Ubiquinol Cytochrome c Reductase, which is achieved by allowance of the physiological turnover of the Rieske protein (UQCRFS1). It also participates in the clearance of UQCRFS1 N-terminal fragments which are produced by the addition of UQCRFS1 into the Ubiquinol Cytochrome c Reductase and whose presence may lead to the failure of the complex's catalytic activity.
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In enzymology, an isohexenylglutaconyl-CoA hydratase () is an enzyme that catalyzes the chemical reaction :3-hydroxy-3-(4-methylpent-3-en-1-yl)glutaryl- CoA \rightleftharpoons 3-(4-methylpent-3-en-1-yl)pent-2-enedioyl-CoA + H2O Hence, this enzyme has one substrate, 3-hydroxy-3-(4-methylpent-3-en-1-yl)glutaryl-CoA, and two products, 3-(4-methylpent-3-en-1-yl)pent-2-enedioyl-CoA and H2O. This enzyme belongs to the family of lyases, specifically the hydro-lyases, which cleave carbon- oxygen bonds. The systematic name of this enzyme class is 3-hydroxy-3-(4-methylpent-3-en-1-yl)glutaryl-CoA hydro-lyase [3-(4-methylpent-3-en-1-yl)pent-2-enedioyl-CoA-forming]. Other names in common use include 3-hydroxy-3-isohexenylglutaryl-CoA-hydrolase, isohexenylglutaconyl coenzyme A hydratase, beta-isohexenylglutaconyl-CoA-hydratase, and 3-hydroxy-3-(4-methylpent-3-en-1-yl)glutaryl-CoA hydro-lyase.
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In enzymology, a 3-hydroxy-3-isohexenylglutaryl-CoA lyase () is an enzyme that catalyzes the chemical reaction :3-hydroxy-3-(4-methylpent-3-en-1-yl)glutaryl- CoA \rightleftharpoons 7-methyl-3-oxooct-6-enoyl-CoA + acetate Hence, this enzyme has one substrate, 3-hydroxy-3-(4-methylpent-3-en-1-yl)glutaryl-CoA, and two products, 7-methyl-3-oxooct-6-enoyl-CoA and acetate. This enzyme belongs to the family of lyases, specifically the oxo-acid-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is 3-hydroxy-3-(4-methylpent-3-en-1-yl)glutaryl-CoA acetate-lyase (7-methyl-3-oxooct-6-enoyl-CoA-forming). Other names in common use include beta-hydroxy-beta-isohexenylglutaryl CoA-lyase, hydroxyisohexenylglutaryl- CoA:acetatelyase, 3-hydroxy-3-isohexenylglutaryl coenzyme A lyase, 3-hydroxy-3-isohexenylglutaryl-CoA isopentenylacetoacetyl-CoA-lyase, and 3-hydroxy-3-(4-methylpent-3-en-1-yl)glutaryl-CoA acetate-lyase.
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In 2010, a structure of truncated human ATP citrate lyase was determined using X-ray diffraction to a resolution of 2.10 Å. In 2019, a full length structure of human ACLY in complex with the substrates coenzyme A, citrate and Mg.ADP was determined by X-ray crystallography to a resolution of 3.2 Å. Moreover, in 2019 a full length structure of ACLY in complex with an inhibitor was determined by cryo-EM methods to a resolution of 3.7 Å. Additional structures of heteromeric ACLY-A/B from the green sulfur bacteria Chlorobium limicola and the archaeon Methanosaeta concilii show that the architecture of ACLY is evolutionarily conserved. Full length ACLY structures showed that the tetrameric protein oligomerizes via its C-terminal domain. The C-terminal domain had not been observed in the previously determined truncated crystal structures. The C-terminal region of ACLY assembles in a tetrameric module that is structurally similar to citryl-CoA lyase (CCL) found in deep branching bacteria.
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In his books, newsletter, and interviews, Sinatra advocates treatment approaches that combine conventional medical therapies with nutritional and mind-body therapies that he thinks enhance the body’s natural bioenergetics and heal the heart. He promotes his ideas of five specific pillars of cardiac health: #an anti-inflammatory diet rich in fresh fruit and vegetables, whole grains, fish, nuts, and healthy oils, similar to the Mediterranean diet [Sinatra has also developed an anti-inflammatory, low-glycemic nutrition plan called the Pan- Asian / Modified Mediterranean (PAMM) Diet]; #nutritional supplementation that includes a high-potency multi-nutrient, fish oil, magnesium, vitamin C, and coenzyme Q10; #regular exercise; #detoxification; and #stress reduction.Stephen Sinatra’s Heart, Health & Nutrition, February 2008 Sinatra believes in the impact one’s emotions have on overall health and the need to resolve so called emotional blockages as well as physical ones. He has stated that “whenever you confront a person with an illness, you have to involve everything, including the spiritual.
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Until July 2018, Liang has published 239 papers and 38 reviews/book chapters. Robust research in the field of biochemistry and structural biology has been going on the Liang Tong lab, and Liang is a dedicated and productive protein crystallographer. He participated or lead the solving of the structures of proteins and protein complexes including, but not limited to, the heterotrimer core of Saccharomyces cerevisiae AMPK homologue SNF1, 5’-3’ exoribonuclease Rat1 and its activating partner Rai1, the a6b6 holoenzyme of propionyl- coenzyme A carboxylase, human symplekin-Ssu72-CTD phosphopeptide complex, histone mRNA stem-loop,human stem-loop binding protein and 3’hExo ternary complex, human phosphofructokinase-1, and the 500-kDa yeast acetyl-CoA carboxylase holoenzyme dimer using X-ray crystallography. In addition to structural studies, Liang also contributed to the understanding of the biological mechanisms and macro molecule interactions by combining a variety of biochemical and molecular biology approaches with structural analysis.
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Carnitine is both a nutrient and made by the body as needed; it serves as a substrate for important reactions in which it accepts and gives up an acyl group. Acetylcarnitine is the most abundant naturally occurring derivative and is formed in the reaction: :acetyl-CoA + carnitine CoA + acetylcarnitine where the acetyl group displaces the hydrogen atom in the central hydroxyl group of carnitine. Coenzyme A (CoA) plays a key role in the Krebs cycle in mitochondria, which is essential for the production of ATP, which powers many reactions in cells; acetyl-CoA is the primary substrate for the Krebs cycle, once it is de-acetylated, it must be re-charged with an acetyl-group in order for the Krebs cycle to keep working. Most cell types appear to have transporters to import carnitine and export acyl-carnitines, which seems to be a mechanism to dispose of longer-chain moieties; however many cell types can also import ALCAR.
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D-amino acid + H2O + acceptor <=> a 2-oxo acid + NH3 \+ reduced acceptor This reaction is distinct from the oxidation reaction catalysed by D-amino acid oxidase that uses oxygen as a second substrate, as the dehydrogenase can use many different compounds as electron acceptors, with the physiological substrate being coenzyme Q. D-amino acid dehydrogenase is an enzyme that catalyzes NADPH from NADP+ and D- glucose to produce D- amino acids and glucose dehydrogenase. Some but not limited to these amino acids are D-leucine, D-isoleucine, and D-Valine, which are essential amino acids that humans cannot synthesize due to the fact that they are not included in their diet. Moreover, D- amino acids catalyzes the formation of 2-oxo acids to produce D- amino acids in the presence of DCIP which is an electron acceptor. D-amino acids are used as components of pharmaceutical products, such as antibiotics, anticoagulants, and pesticides, because they have been shown to be not only more potent than their L enantiomers, but also more resistant to enzyme degradation.
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However, it is also used in other cellular processes, most notably as a substrate of enzymes in adding or removing chemical groups to or from, respectively, proteins, in posttranslational modifications. Because of the importance of these functions, the enzymes involved in NAD metabolism are targets for drug discovery. In organisms, NAD can be synthesized from simple building-blocks (de novo) from either tryptophan or aspartic acid, each a case of an amino acid; alternatively, more complex components of the coenzymes are taken up from nutritive compounds such as niacin; similar compounds are produced by reactions that break down the structure of NAD, providing a salvage pathway that “recycles” them back into their respective active form. Some NAD is converted into the coenzyme nicotinamide adenine dinucleotide phosphate (NADP); its chemistry largely parallels that of NAD, though predominantly its role is as a cofactor in anabolic metabolism. The NAD chemical species’ superscripted addition sign reflects the formal charge on one of its nitrogen atoms; this species’ actually a singly charged anion — carrying a (negative) ionic charge of 1 — under conditions of physiological pH.
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The free-floating fatty acids, released from adipose tissues to the blood, bind to carrier protein molecule known as serum albumin that carry the fatty acids to the cytoplasm of target cells such as the heart, skeletal muscle, and other tissue cells, where they are used for fuel. But before the target cells can use the fatty acids for ATP production and β oxidation, the fatty acids with chain lengths of 14 or more carbons must be activated and subsequently transported into mitochondrial matrix of the cells in three enzymatic reactions of the carnitine shuttle. The first reaction of the carnitine shuttle is a two-step process catalyzed by a family of isozymes of acyl-CoA synthetase that are found in the outer mitochondrial membrane, where they promote the activation of fatty acids by forming a thioester bond between the fatty acid carboxyl group and the thiol group of coenzyme A to yield a fatty acyl–CoA. In the first step of the reaction, acyl-CoA synthetase catalyzes the transfer of adenosine monophosphate group (AMP) from an ATP molecule onto the fatty acid generating a fatty acyl–adenylate intermediate and a pyrophosphate group (PPi).
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Each monomer in the complex has a substrate binding site that binds to G6P, and a catalytic coenzyme binding site that binds to NADP+/NADPH using the Rossman fold. For some higher organisms, such as humans, G6PD contains an additional NADP+ binding site, called the NADP+ structural site, that does not seem to participate directly in the reaction catalyzed by G6PD. The evolutionary purpose of the NADP+ structural site is unknown. As for size, each monomer is approximately 500 amino acids long (514 amino acids for humans). Functional and structural conservation between human G6PD and Leuconostoc mesenteroides G6PD points to 3 widely conserved regions on the enzyme: a 9 residue peptide in the substrate binding site, RIDHYLGKE (residues 198-206 on human G6PD), a nucleotide-binding fingerprint, GxxGDLA (residues 38-44 on human G6PD), and a partially conserved sequence EKPxG near the substrate binding site (residues 170-174 on human G6PD), where we have use "x" to denote a variable amino acid. The crystal structure of G6PD reveals an extensive network of electrostatic interactions and hydrogen bonding involving G6P, 3 water molecules, 3 lysines, 1 arginine, 2 histidines, 2 glutamic acids, and other polar amino acids.
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