SCl2 hydrolyzes with release of HCl. Old samples contain Cl2.
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MoCl5 is an aggressive oxidant and readily hydrolyzes to release HCl.
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Upon prolonged exposure to aqueous solutions phlorizin hydrolyzes to phloretin and glucose.
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It is metabolized by alpha-galactosidase, which hydrolyzes the terminal alpha linkage.
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VCl4 is a volatile, aggressive oxidant that readily hydrolyzes to release HCl.
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This site binds negatively charged calcium phytate and hydrolyzes phosphates from it.
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WCl6 is an aggressively corrosive oxidant, and hydrolyzes to release hydrogen chloride.
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Niobium chloride rapidly oxidizes and hydrolyzes in air to form niobium(V) oxide.
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It slowly hydrolyzes back to perchloric acid, which is also hazardous when anhydrous.
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TiBr4 hydrolyzes rapidly, potentially dangerously, to release hydrogen bromide, otherwise known as hydrobromic acid.
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TCNE hydrolyzes in moist air to give hydrogen cyanide and should be handled accordingly.
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It hydrolyzes readily to an oxychloride. The lower halides and , feature Ta-Ta bonds.
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SHMP hydrolyzes in aqueous solution, particularly under acidic conditions, to sodium trimetaphosphate and sodium orthophosphate.
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HBF4 is toxic and attacks skin and eyes. It attacks glass. It hydrolyzes, releasing corrosive, volatile hydrogen fluoride.
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The short form is expressed in adipose tissue, among others, where it hydrolyzes stored triglycerides to free fatty acids.
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Like related tetrabromides of Ti and Hf, ZrBr4 hydrolyzes readily to give oxy-bromide, with release of hydrogen bromide.
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This gene encodes a protein that specifically hydrolyzes cAMP. Alternate transcriptional splice variants, encoding different isoforms, have been characterized.
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The thiocarbenium ion hydrolyzes to form the hemithioacetal: 650px After formation, the hemithioacetal breaks into hydrogen peroxide, farnesal, and cysteine.
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Triphenylmethyl hexafluorophosphate is a brown powder that hydrolyzes readily to triphenylmethanol. It is used as a catalyst and reagent in organic syntheses.
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It is believed that ACP hydrolyzes under physiological temperatures and pH to form octacalcium phosphate as an intermediate, and then surface apatite.
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An isopeptidase is a protease enzyme that hydrolyzes isopeptide bonds, or amide bonds that occur outside the main chain in a polypeptide chain.
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PDE4 hydrolyzes cyclic adenosine monophosphate (cAMP) to inactive adenosine monophosphate (AMP). Inhibition of PDE4 blocks hydrolysis of cAMP, thereby increasing levels of cAMP within cells.
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DEHP hydrolyzes to mono-ethylhexyl phthalate (MEHP) and subsequently to phthalate salts. The released alcohol is susceptible to oxidation to the aldehyde and carboxylic acid.
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However, some bacterial cells have the enzyme β-lactamase, which hydrolyzes the beta-lactam ring, rendering the drug inactive. This contributes to antibacterial resistance towards cefalexin.
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Phosphodiesterase type 5 (PDE5), which is abundant in the pulmonary tissue, hydrolyzes the cyclic bond of cGMP. Consequently, the concentration of cGMP (and thus PKG activity) decreases.
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Cyanogen bromide hydrolyzes peptide bonds at the C-terminus of methionine residues. This reaction is used to reduce the size of polypeptide segments for identification and sequencing.
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As a solid, it is relatively stable against decomposition. In contact with water however it hydrolyzes with release of oxygen. Upon treatment with acid, it forms hydrogen peroxide.
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Alkali salts or basic salts are salts that are the product of incomplete neutralization of a strong base and a weak acid. Rather than being neutral (as some other salts), alkali salts are bases as their name suggests. What makes these compounds basic is that the conjugate base from the weak acid hydrolyzes to form a basic solution. In sodium carbonate, for example, the carbonate from the carbonic acid hydrolyzes to form a basic solution.
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The enzyme phosphotriesterase hydrolyzes organophosphate compounds by cleaving the triester linkage in the substrate. Organophosphate compounds that serve as substrates for enzyme-catalyzed hydrolysis by PTE. The enzyme has a very broad substrate specificity, and is very efficient in catalyzing the reaction: PTE hydrolyzes paraoxon at a rate approaching the diffusion limit, which indicates that the enzyme is optimally evolved for using this substrate. It acts specifically on synthetic organophosphate triesters and phosphorofluoridates.
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The Mg2+ located in the active site activates a water molecule to produce an hydroxide ion, which then hydrolyzes the phosphorylated aspartate and regenerates an active enzyme while releasing phosphate.
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The enzyme quercitrinase can be found in Aspergillus flavus. This enzyme hydrolyzes the glycoside quercitrin to release quercetin and L-rhamnose. It is an enzyme in the rutin catabolic pathway.
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CDI hydrolyzes readily to give back imidazole: :(C3H3N2)2CO + H2O → 2 C3H4N2 \+ CO2 The purity of CDI can be determined by the amount of CO2 that is formed upon hydrolysis.
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Pancreatin contains the pancreatic enzymes trypsin, amylase and lipase. A similar mixture of enzymes is sold as pancrelipase, which contains more active lipase enzyme than does pancreatin. The trypsin found in pancreatin works to hydrolyze proteins into oligopeptides; amylase hydrolyzes starches into oligosaccharides and the disaccharide maltose; and lipase hydrolyzes triglycerides into fatty acids and glycerols. Pancreatin is an effective enzyme supplement for replacing missing pancreatic enzymes, and aids in the digestion of foods in cases of pancreatic insufficiency.
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Reactions with organomagnesium compounds, alcohols, amines, and ammonia yield adduction compounds. Fluorosilicic acid, a derivative of SiF4, is a strong acid in aqueous solution (the anhydrous form does not exist). Pnictogens (nitrogen's periodic table column) show very similar trends in reactivity and acidity of the highest fluorides (pentafluorides) and most common ones (trifluorides), with the said property increasing down the group: NF3 is stable against hydrolysis, PF3 hydrolyzes very slowly in moist air, while AsF3 completely hydrolyzes.
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Vanadium oxytrichloride is the inorganic compound with the formula VOCl3. This yellow distillable liquid hydrolyzes readily in air. It is an oxidizing agent. It is used as a reagent in organic synthesis.
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Zirconium(IV) chloride, also known as zirconium tetrachloride, () is an inorganic compound frequently used as a precursor to other compounds of zirconium. This white high-melting solid hydrolyzes rapidly in humid air.
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PLA1 hydrolyzes nonionic substrates preferentially over ionic substrates. Optimum pH conditions for PLA1 activity on neutral phospholipids is around 7.5, whereas the optimal conditions for PLA1 activity on acidic phospholipids is around 4.
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Microtubules are polymers of tubulin subunits arranged in cylindrical tubes. The subunit is made up of alpha and beta tubulin. GTP binds to alpha tubulin irreversibly. Beta tubulin binds GTP and hydrolyzes to GDP.
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Exo-poly-alpha-D-galacturonosidase () (exoPG) hydrolyzes peptic acid from the non-reducing end, releasing digalacturonate. PG and exoPG share a few regions of sequence similarity, and belong to family 28 of the glycosyl hydrolases.
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Lactonase hydrolyzes the ester bond of the homoserine lactone ring of acylated homoserine lactones. In hydrolysing the lactone bond, lactonase prevents these signaling molecules from binding to their target transcriptional regulators, thus inhibiting quorum sensing.
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In the first stage, ammonia and carbamate are produced. The carbamate spontaneously and rapidly hydrolyzes to ammonia and carbonic acid. Urease activity increases the pH of its environment as ammonia is produced, which is basic.
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Borazine is a colourless liquid with an aromatic smell. In water it hydrolyzes to boric acid, ammonia, and hydrogen. Borazine, with a standard enthalpy change of formation ΔHf of −531 kJ/mol, is thermally very stable.
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It preferentially hydrolyzes linoleoyl-containing phosphatidylcholine substrates. Secretion of this enzyme is thought to induce inflammatory responses in neighboring cells. Alternatively spliced transcript variants have been found, but their full-length nature has not been determined.
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Other bacterial applications of nitrilases produced by plant-associated microorganisms include the degradation of plant nitriles for a carbon and nitrogen source. P. fluorescens EBC191 hydrolyzes many arylacetonitriles, namely mandelonitrile, which serves as a defense against herbivores.
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Fluorosulfuric acid is considered to be highly toxic and extremely corrosive. It hydrolyzes to release HF. Addition of water to HSO3F can be violent, similar to the addition of water to sulfuric acid but much more violent.
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The compound slowly hydrolyzes: :CSCl4 \+ 2H2O → CO2 \+ 4HCl + S The compound is corrosive to most metals. It reacts with iron, evolving carbon tetrachloride. Perchloromethyl mercaptan is oxidized by nitric acid to trichloromethanesulfonyl chloride (Cl3CSO2Cl), a white solid.
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1,3-propane sultone is an activated ester and is susceptible to nucleophilic attack. It hydrolyzes to the acid. :Hydrolysis of Propane-1,3-sultone It has been used in the synthesis of specialist surfactants, such as CHAPS detergent.
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Thionyl fluoride can be produced by the reaction of thionyl chloride with fluoride sources such as antimony trifluoride.W. C. Smith, E. L. Muetterties "Thionyl Fluoride" Inorganic Syntheses 1960, Volume 6, pages: 162-163. :3 SOCl2 \+ 2SbF3 → 3SOF2 \+ 2SbCl3 Alternatively, it arises via the fluorination of sulfur dioxide: :SO2 \+ 2PF5 → SOF2 \+ POF3 Thionyl fluoride arises as a fleeting intermediate from the decomposition of sulfur hexafluoride as the result of electrical discharges which generate sulfur tetrafluoride. SF4 hydrolyzes to give thionyl fluoride, which in turn hydrolyzes further as described below.
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Glycoside hydrolase family 19 is a group of endo-acting enzymes that hydrolyzes the glycosidic bonds of β-1,4-linked N-Acetylglucosamine (GlcNAc) typically within chitin; however, some enzymes in this family also demonstrate lysozyme activity. Since bacterial cell walls do not contain chitin, OBPgp279 hydrolyzes β-1,4-linked GlcNAc in peptidoglycan. The hydrolysis of β-1,4-linked GlcNAc is catalyzed by two glutamate residues in the active side, one acting as a general acid, and another acting as a general base. There is limited detail on the catalytic mechanism of OBPgp279.
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The chemistry of maleic anhydride is very rich, reflecting its ready availability and bifunctional reactivity. It hydrolyzes, producing maleic acid, cis-HOOC-CH=CH-COOH. With alcohols, the half-ester is generated, e.g., cis-HOOC-CH=CH-COOCH3.
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When TcdB binds to Rho and other small GTPases, GTP hydrolyzes to GDP, which leads to GTP-bound (active) to GDP-bound (inactive) (Fig. 5). In addition, this interchange activity is regulated by guanine factors in the cell's cytosol.
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To further raise the yield to approximately 60%, which is thought to be so low since neopullulanase hydrolyzes starch less efficiently than pullunan and other oligosaccharides, saccharifying alpha- amylase sourced from Bacillus subtilis may be added to the solution.
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The high-molecular-weight polymer hydrolyzes in hot water to form the trimethyl isocyanurate. Since catalytic metal salts can be formed from impurities in commercial grade MIC and steel, this product must not be stored in steel drums or tanks.
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The glucuronide 4-methylumbelliferyl-β-D- glucuronide (MUG) is used to test for the presence of Escherichia coli. E. coli produces the enzyme β-glucuronidase, which hydrolyzes the MUG molecule to a fluorescent product that is detectable under ultraviolet light.
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Calcium cyanide hydrolyzes readily to form hydrogen cyanide gas. The presence of acid accelerated evolution of hydrogen cyanide gas. It is reactive toward oxidizing agents. Calcium cyanide is also sometimes used to produce ammonium cyanide by reacting it with ammonium carbonate.
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In the second step of the reaction, a water molecule is activated by the charge-relay His297-Glu153 pair, and undergoes nucleophilic attack on the Cγ of Asp129. This hydrolyzes the ester group, liberating the hydrolysis product as a vicinal diol.
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Sulfur dibromide is the chemical compound with the formula SBr. It is a toxic gas. Sulfur dibromide readily decomposes into SBr and elemental bromine. In analogy to sulfur dichloride, it hydrolyzes in water to give hydrogen bromide, sulfur dioxide and elemental sulfur.
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When the 50S subunit joins, it hydrolyzes GTP to GDP and Pi, causing a conformational change in the IF2 that causes IF2 to release and allow the 70S ribosome to form. Human mitochondria use a nuclear-encoded homolog, MTIF2, for translation initiation.
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The insecticides, mostly used in liquid form, contain between 50% and 90% chlorfenvinphos. The substance easily mixes with acetone, ethanol, and propylene glycol. Furthermore, chlorfenvinphos is corrosive to metal and hydrolyzes in the environment.[U.S. Department of Health and Human Services. 1997.
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PLC-β in turn hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) to diacyl glycerol (DAG) and inositol trisphosphate (IP3). IP3 acts as a second messenger to release stored calcium into the cytoplasm, while DAG acts as a second messenger that activates protein kinase C (PKC).
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Niobium(V) chloride, also known as niobium pentachloride, is a yellow crystalline solid. It hydrolyzes in air, and samples are often contaminated with small amounts of NbOCl3. It is often used as a precursor to other compounds of niobium. NbCl5 may be purified by sublimation.
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EPN, via its oxygen analog EPNO generated by metabolism, causes delayed neurotoxicity. It is an acetylcholinesterase (AChE) inhibitor. AChE is an enzyme that hydrolyzes acetylcholine, an excitatory neurotransmitter. When acetylcholine is released into the synaptic cleft, the postsynaptic action is not terminated by reuptake.
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Although it was originally used for the desymmetrizing hydrolysis of glutarate esters,Cohen, S.; Khedouri, E. J. Am. Chem. Soc. 1961, 83, 1093. PLE also hydrolyzes malonates, cyclic diesters, monoesters, and other substrates. Active site models have been advanced to explain the selectivity of PLE.
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NTPDase1 is an ectonucleotidase that catalyse the hydrolysis of γ- and β-phosphate residues of triphospho- and diphosphonucleosides to the monophosphonucleoside derivative. NTPDase1 hydrolyzes P2 receptor ligands, namely ATP, ADP, UTP and UDP with similar efficacy. NTPDase1 can therefore effect P2 receptor activation and functions.
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Exposure to even small amounts may cause convulsions or death. LD50 orally in rats is reported as 25–50 mg/kg. The recommended method to deactivate cyanogen bromide is with bleach. The aqueous alkali hydroxide instantly hydrolyzes (CN)Br to alkali cyanide and bromide.
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Solid samples of sodium ethoxide gradually turn dark on storage in dry air because of oxidation.M. Eagleson "Concise encyclopedia chemistry" p.997. In moist air, it hydrolyzes rapidly to sodium hydroxide. The conversion is not obvious and typical samples of NaOEt are contaminated with NaOH.
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PON1 hydrolyzes the active metabolites in several OP insecticides such as chlorpyrifos oxon, and diazoxon, as well as, nerve agents such as soman, sarin, and VX. PON1 hydrolyzes the metabolites, not the parent compounds of insectides. The presence of PON1 polymorphisms causes there to be different enzyme levels and catalytic efficiency of this esterase, which in turn suggests that different individuals may be more susceptible to the toxic effect of OP exposure. Higher levels of PON1 plasma hydrolytic activity provide a greater degree of protection against OP pesticides. Rats injected with purified PON1 from rabbit serum were more resistant to acute cholinergic activity than the control rats.
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It reduces aldehydes but not most ketones. It is especially suitable for reductive aminations of aldehydes and ketones. However, unlike sodium cyanoborohydride, the triacetoxyborohydride hydrolyzes readily, nor is it compatible with methanol. It reacts only slowly with ethanol and isopropanol and can be used with these.
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The switch is turned off when the G protein hydrolyzes its own bound GTP, converting it back to GDP. But before that occurs, the active protein has an opportunity to diffuse away from the receptor and deliver its message for a prolonged period to its downstream target.
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The compound is prepared by a redistribution reaction by combining stannic chloride and tetrabutyltin: :3 (C4H9)4Sn + SnCl4 → 4 (C4H9)3SnCl Tributyltin chloride hydrolyzes to the oxide [(C4H9)3Sn]2O Tributyltin chloride is used as a precursor to other organotin compounds and reagents, such as tributyltin hydride.
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Arylsulfonic acids are susceptible to hydrolysis, the reverse of the sulfonation reaction. Whereas benzene sulfonic acid hydrolyzes above 200 ″C, most related derivatives are easier to hydrolyze. Thus, heating aryl sulfonic acids in aqueous acid produces the parent arene. This reaction is employed in several scenarios.
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Under mildly acidic conditions, cycloserine hydrolyzes to give hydroxylamine and D-serine. Cycloserine can be conceptualized as a cyclized version of serine, with an oxidative loss of dihydrogen to form the nitrogen-oxygen bond. Cycloserine is stable under basic conditions, with the greatest stability at pH = 11.5.
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Sucrase is a digestive enzyme that catalyzes the hydrolysis of sucrose to its subunits fructose and glucose. One form, sucrase-isomaltase, is secreted in the small intestine on the brush border. The sucrase enzyme invertase, which occurs more commonly in plants, also hydrolyzes sucrose but by a different mechanism.
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Titanium ethoxide is a chemical compound with the formula Ti4(OCH2CH3)16. It is a colorless liquid that is soluble in organic solvents but hydrolyzes readily. It is sold commercially as a colorless solution. Alkoxides of titanium(IV) and zirconium(IV) are used in organic synthesis and materials science.
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Chemical structure of 1-arseno-3-phosphoglycerate 1-Arseno-3-phosphoglycerate is a compound produced by the enzyme glyceraldehyde 3-phosphate dehydrogenase from glyceraldehyde 3-phosphate and arsenate in the glycolysis pathway. The compound is unstable and hydrolyzes spontaneously to 3-phosphoglycerate, bypassing the energy producing step of glycolysis.
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The factor consists of an alpha, beta, and gamma subunit. The eIF2 gamma subunit is characterized by a GTP-binding domain and beta-barrel folds. It binds to the tRNA through GTP. Once the initiation factor helps the tRNA bind, the GTP hydrolyzes and is released the eIF2.
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Titanyl sulfate is the inorganic compound with the formula TiOSO4. It is a white solid that forms by treatment of titanium dioxide with fuming sulfuric acid. It hydrolyzes to a gel of hydrated titanium dioxide. The structure consists of dense polymeric network with tetrahedral sulfur and octahedral titanium centers.
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For example, whereas the pancreatic esterase is selective for short-chain retinyl esters, the brush-border membrane enzyme preferentially hydrolyzes retinyl esters containing a long- chain fatty acid such as palmitate or stearate. Retinol enters the absorptive cells of the small intestine, preferentially in the all-trans-retinol form.
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Heating or irradiation with UV light regenerates the ketene monomer: :(C2H2O)2 2 CH2CO Alkylated ketenes also dimerize with ease and form substituted diketenes. Diketene readily hydrolyzes in water forming acetoacetic acid. Its half-life in water is approximately 45 min. a 25 °C at 2 < pH < 7.
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Croconate acid blue is strongly acidic (pKa1 ≈ 1). It crystallizes from water as a purple sesquihydrate · and gives a red solution in acetone or ethanol, but deep blue in water. It hydrolyzes slowly in water to give croconic acid violet. Extended heating in water produces deep green plates, apparently a polymer.
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Alzheimer's disease is characterized by the impairment of cholinergic function. One hypothesis is that this impairment contributes to the cognitive deficits caused by the disease. This hypothesis forms the basis for use of galantamine as a cholinergic enhancer in the treatment of Alzheimer's. Galantamine inhibits acetylcholinesterase, an enzyme which hydrolyzes acetylcholine.
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1) Base-catalyzed deprotonation of the 2′-OH group, enabling the deprotonated 2′ hydroxyl's nucleophilic attack on the adjacent phosphorus. 2) Transition state. 3) Phosphodiester bond is broken, cleaving the RNA backbone. 4) The 2′,3′-cyclic phosphate group (in step 3) hydrolyzes to either the 2′ or 3′ phosphate.
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Carboxypeptidase A, from bovine pancreas A carboxypeptidase (EC number 3.4.16 - 3.4.18) is a protease enzyme that hydrolyzes (cleaves) a peptide bond at the carboxy-terminal (C-terminal) end of a protein or peptide. This is in contrast to an aminopeptidases, which cleave peptide bonds at the N-terminus of proteins.
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The enzyme first selectively hydrolyzes alpha-1,4-glucosidic bonds on the nonreducing side of pullulan's alpha-1,6-glucosidic bonds, producing panose and panose-containing intermediates. These intermediates then have their alpha-1,4- and alpha-1,6-glucosidic bonds hydrolyzed to form additional panose along with smaller quantities of maltose and glucose.
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S2Cl2 hydrolyzes to sulfur dioxide and elemental sulfur. When treated with hydrogen sulfide, polysulfanes are formed as indicated in the following idealized formula: :2 H2S + S2Cl2 → H2S4 \+ 2 HCl It reacts with ammonia to give heptasulfur imide (S7NH) and related S−N rings S8−x(NH)x (x = 2, 3).
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Eosinophil lysophospholipase is an enzyme that in humans is encoded by the CLC gene. Lysophospholipases are enzymes that act on biological membranes to regulate the multifunctional lysophospholipids. The protein encoded by this gene is a lysophospholipase expressed in eosinophils and basophils. It hydrolyzes lysophosphatidylcholine to glycerophosphocholine and a free fatty acid.
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As expected from the behavior of the other thionyl halides, this compound hydrolyzes readily, giving hydrogen fluoride and sulfur dioxide: :SOF2 \+ H2O → 2 HF + SO2 In contrast to thionyl chloride and bromide, thionyl fluoride is not useful for halogenation. The related derivative, sulfur tetrafluoride is however useful for that purpose.
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Potassium amide is an inorganic compound with the chemical formula KNH2. Like other alkali metal amides, it is a white solid that hydrolyzes readily. It is a strong base. :Traditionally KNH2 is viewed as a simple salt, but it is a covalent compound that is highly aggregated in ammonia solution.
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In warm solution, quinazoline hydrolyzes under acidic and alkaline conditions to 2-aminobenzaldehyde (or the products of its self-condensation) and formic acid and ammonia/ammonium.Büchel, K. H., ed. Methods of Organic Chemistry (Houben- Weyl): Additional and Supplementary Volumes to the 4th Edition. New York: Georg Thieme Verlag Stuttgart, 2001.
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Aminoacylase 1 (ACY1: EC 3.5.14) is a zinc binding enzyme which hydrolyzes N-acetyl amino acids into the free amino acid and acetic acid. Of the N-acetyl amino hydrolyzing enzymes, aminoacylase 1 is the most common. The ACY1 gene is located on the short arm of chromosome 3 (3p21.2).
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The main application is as a substitute for urea in fertilizers. Oxamide hydrolyzes (releases ammonia) very slowly, which is sometimes preferred vs the quick release by urea. It is used as a stabilizer for nitrocellulose preparations. It also finds use in APCP rocket motors as a high performance burn rate suppressant.
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PDE4 is an isoenzyme that hydrolyzes cyclic AMP to regulate human bronchial tone (along with PDE3). Yet as a PDE4 inhibitor, glaucine possesses very low potency. Glaucine has also recently been found to have an effect on the neuronal 5-HT2A receptors, which are responsible for the hallucinogenic effects of classical psychedelics.
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Methyl phosphonic dichloride is an organophosphorus compound. It has a number of potential uses but is most notable as being a precursor to several chemical weapons agents. It is a white crystalline solid, with a low melting point. It hydrolyzes readily and must be handled with care as it is exceedingly toxic.
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BCl3 hydrolyzes readily to give hydrochloric acid and boric acid: :BCl3 \+ 3 H2O → B(OH)3 \+ 3 HCl Alcohols behave analogously giving the borate esters, e.g. trimethyl borate. Ammonia forms a Lewis adduct with boron trichloride. As a strong Lewis acid, BCl3 forms adducts with tertiary amines, phosphines, ethers, thioethers, and halide ions.
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In the blood Lp-PLA2 travels mainly with low-density lipoprotein (LDL). Less than 20% is associated with high-density lipoprotein HDL. Several lines of evidence suggest that HDL-associated Lp-PLA2 may substantially contribute to the HDL antiatherogenic activities. It is an enzyme produced by inflammatory cells and hydrolyzes oxidized phospholipids in LDL.
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Acyl-protein thioesterase 1 is an enzyme that in humans is encoded by the LYPLA1 gene. Lysophospholipases are enzymes that act on biological membranes to regulate the multifunctional lysophospholipids. The protein encoded by this gene hydrolyzes lysophosphatidylcholine in both monomeric and micellar forms. The use of alternate polyadenylation sites has been found for this gene.
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Trithionate is an oxyanion of sulfur with the chemical formula [S3O6]2−. It is the conjugate base of trithionic acid.Dilute NaOH hydrolyzes S4N4 as follows, yielding thiosulfate and trithionate: 2 S4N4 + 6 OH− + 9 H2O → S2O2− 3 + 2 S3O2− 6 + 8 NH3 Certain sulfate-reducing bacteria have been known to use the compound in respiration.
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In solution, lead(II) hydroxide is a somewhat weak base, forming lead(II) ion, Pb2+, under weakly acidic conditions. This cation hydrolyzes and, under progressively increasing alkaline conditions, forms Pb(OH)+, Pb(OH)2(aqueous), Pb(OH)3−, and other species, including several polynuclear species, e.g., Pb4(OH)44+, Pb3(OH)42+, Pb6O(OH)64+.
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Synthesis of NTDA Naphthalenetetracarboxylic dianhydride is prepared by oxidation of pyrene. Typical oxidants are chromic acid and chlorine. The unsaturated tetrachloride hydrolyzes to enols that tautomerize to the bis- dione, which in turn can be oxidized to the tetracarboxylic acid.F. Röhrscheid "Carboxylic Acids, Aromatic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2012.
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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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Dimethylaminoethyl acrylate is a clear, colorless to slightly yellowish liquid with a pungent amine-like odor. It is miscible with water, reacts bases and hydrolyzes rapidly to acrylic acid and dimethylaminoethanol. It can form ignitable mixtures with air. DMAEA tends to spontaneously polymerize at elevated temperatures, upon irradiation, and in the presence of free-radical initiators.
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Titanocene dichloride is the organotitanium compound with the formula (η5-C5H5)2TiCl2, commonly abbreviated as Cp2TiCl2. This metallocene is a common reagent in organometallic and organic synthesis. It exists as a bright red solid that slowly hydrolyzes in air. It shows antitumour activity and was the first non-platinum complex to undergo clinical trials as a chemotherapy drug.
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Lemon juice is used to make lemonade, soft drinks, and cocktails. It is used in marinades for fish, where its acid neutralizes amines in fish by converting them into nonvolatile ammonium salts. In meat, the acid partially hydrolyzes tough collagen fibers, tenderizing it. In the United Kingdom, lemon juice is frequently added to pancakes, especially on Shrove Tuesday.
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Arsenic pentasulfide hydrolyzes in boiling water, giving arsenous acid and sulfur: : As2S5 \+ 6 H2O → 2 H3AsO3 \+ 2 S + 3 H2S It oxidizes in air at elevated temperatures producing arsenic oxides, the products and yields of which are variable. In alkali metal sulfide solutions arsenic pentasulfide forms a thioarsenate anion, [AsS4]3−, which contain As(V) centres.
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Deoxyribonuclease gamma is an enzyme that in humans is encoded by the DNASE1L3 gene. This gene encodes a member of the DNase family. The protein hydrolyzes DNA, is not inhibited by actin, and mediates the breakdown of DNA during apoptosis. Alternate transcriptional splice variants of this gene have been observed but have not been thoroughly characterized.
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Beryllium chloride is stable in dry air. Beryllium chloride is a Lewis acid and has been used as a catalyst in some organic reactions. It hydrolyzes, evolving hydrogen chloride: : BeCl2 \+ 2H2O → Be(OH)2 \+ 2 HCl It forms a tetrahydrate, BeCl2•4H2O ([Be(H2O)4]Cl2). BeCl2 is also soluble in oxygenated solvents such as ethers.
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Cytosolic beta-glucosidase is a predominantly liver enzyme that efficiently hydrolyzes beta-D-glucoside and beta-D-galactoside, but not any known physiologic beta-glycoside, suggesting that it may be involved in detoxification of plant glycosides. GBA3 also has significant neutral glycosylceramidase activity (), suggesting that it may be involved in a non-lysosomal catabolic pathway of glucosylceramide metabolism.
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It is optically active with [α]D24 = +59.79°. The compound slowly hydrolyzes in water: 0.25% of the acetate ester bonds were broken by boiling in water for 1 hour, and 0.20% after standing in water at 40° C for 5 days. Sucrose octaacetate decomposes at about 285 °C, but can be distilled at reduced pressure at 260° C.
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Tolylfluanid hydrolyzes slowly in acidic conditions. The half-life is shorter when the pH is high; at pH = 7, it is at least 2 days. In aerobic media (pH = 7.7-8.0), tolylfluanid hydrolytically and microbially decomposes to N,N-dimethyl-N-(4-methylphenyl) sulfamide (DMST) and dimethylsulfamide. After 14 days, tolylfluanid is generally considered to have degraded.
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Selenium oxydichloride can be prepared by several methods, and a popular one involves the conversion of selenium dioxide to dichloroselenious acid followed by dehydration: :SeO2 \+ 2 HCl → Se(OH)2Cl2 :Se(OH)2Cl2 → SeOCl2 \+ H2O The original synthesis involved the redistribution reaction of selenium dioxide and selenium tetrachloride. The compound hydrolyzes readily to form hydrogen chloride and selenium dioxide.
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Their synthesis is promoted by light. The most heavily studied betalain is betanin, also called beetroot red after the fact that it may be extracted from red beet roots. Betanin is a glucoside, and hydrolyzes into the sugar glucose and betanidin. It is used as a food coloring agent, and the color is sensitive to pH.
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Xaa-Pro dipeptidase is a cytosolic dipeptidase that hydrolyzes dipeptides with proline or hydroxyproline at the carboxy terminus (but not Pro-Pro). It is important in collagen metabolism because of the high levels of imino acids. Mutations at the PEPD locus cause prolidase deficiency. This is characterised by Iminodipeptidurea, skin ulcers, mental retardation and recurrent infections.
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Titanium tetrachloride (titanium(IV) chloride, TiCl4) is a colorless volatile liquid (commercial samples are yellowish) that, in air, hydrolyzes with spectacular emission of white clouds. Via the Kroll process, TiCl4 is used in the conversion of titanium ores to titanium metal. Titanium tetrachloride is also used to make titanium dioxide, e.g., for use in white paint.
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Galactosylceramidase (or galactocerebrosidase) is an enzyme that in humans is encoded by the GALC gene. Galactosylceramidase is an enzyme which removes galactose from ceramide derivatives (galactosylceramides). Galactosylceramidase is a lysosomal protein which hydrolyzes the galactose ester bonds of galactosylceramide, galactosylsphingosine, lactosylceramide, and monogalactosyldiglyceride. Mutations in this gene have been associated with Krabbe disease, also known as galactosylceramide lipidosis.
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The protein encoded by this gene hydrolyzes inosine triphosphate and deoxyinosine triphosphate to the monophosphate nucleotide and diphosphate. The enzyme possesses a multiple substrate-specificity and acts on other nucleotides including xanthosine triphosphate and deoxyxanthosine triphosphate. The encoded protein, which is a member of the HAM1 NTPase protein family, is found in the cytoplasm and acts as a homodimer.
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Sebacoyl chloride (or sebacoyl dichloride) is a di-acyl chloride, with formula (CH2)8(COCl)2. A colorless oily liquid with a pungent odor, it is soluble in hydrocarbons and ethers. Sebacoyl chloride is corrosive; like all acyl chlorides, it hydrolyzes, evolving hydrogen chloride. It is less susceptible to hydrolysis though than shorter chain aliphatic acyl chlorides.
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Trifluoromethyl hypofluorite is an organofluorine compound with the formula . It exists as a colorless gas at room temperature and is highly toxic. It is a rare example of a hypofluorite (compound with an O−F bond). It is prepared by the reaction of fluorine gas with carbon monoxide: :2 F2 \+ CO → CF3OF The gas hydrolyzes only slowly at neutral pH.
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Class III bacteriocins are large, heat-labile (>10 kDa) protein bacteriocins. This class is subdivided in two subclasses: subclass IIIa (bacteriolysins) and subclass IIIb. Subclass IIIa comprises those peptides that kill bacterial cells by cell wall degradation, thus causing cell lysis. The best studied bacteriolysin is lysostaphin, a 27 kDa peptide that hydrolyzes the cell walls of several Staphylococcus species, principally S. aureus.
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Then, a third magnesium weakly and non- cooperatively to the third binding site, which has 5 water molecules and residue Glu70. After all three magnesium ions have bound, the inositol monophosphatase can bind, the negatively charge phosphate group stabilized by the three positively charged magnesium ions. Finally an activated water molecule acts a nucleophile and hydrolyzes the substrate, giving inositol and inorganic phosphate.
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In several bacteria, such as E. coli, proteins tagged with the SsrA peptide (ANDENYALAA) encoded by tmRNA are digested by Clp proteases. The protein encoded by this gene belongs to the peptidase family S14 and hydrolyzes proteins into small peptides in the presence of ATP and magnesium. The protein is transported into mitochondrial matrix and is associated with the inner mitochondrial membrane.
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Alkaline phosphatase primarily hydrolyzes phosphate monoester bonds, but it shows some promiscuity towards hydrolyzing phosphate diester bonds, making it a sort of opposite to NPP. The active sites of these two enzymes show marked similarities, namely in the presence of nearly superimposable Zn2+ bimetallo catalytic centers. In addition to the bimetallo core, AP also has an Mg2+ ion in its active site.
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The renin–angiotensin system, showing role of renin at bottom. The renin enzyme circulates in the bloodstream and hydrolyzes (breaks down) angiotensinogen secreted from the liver into the peptide angiotensin I. Angiotensin I is further cleaved in the lungs by endothelial-bound angiotensin-converting enzyme (ACE) into angiotensin II, the most vasoactive peptide.Brenner & Rector's The Kidney, 7th ed., Saunders, 2004, pp.
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The hydrophobic and shape complementarity between the peptide substrate P1 side chain and the enzyme S1 binding cavity accounts for the substrate specificity of this enzyme. Chymotrypsin also hydrolyzes other amide bonds in peptides at slower rates, particularly those containing leucine and methionine at the P1 position. Structurally, it is the archetypal structure for its superfamily, the PA clan of proteases.
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Titanium butoxide is an metal-organic chemical compound with the formula Ti(OBu)4 (Bu = CH2CH2CH2CH3). It is a colorless odorless liquid, although aged samples are yellowish with a weak alcohol-like odor. It is soluble in many organic solvents. It hydrolyzes to give titanium dioxide, which allows deposition of TiO2 coatings of various shapes and sizes down to the nanoscale.
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Like other titanium alkoxides, titanium butoxide exchanges alkoxide groups: :Ti(OBu)4 \+ HOR → Ti(OBu)3(OR) + HOBu :Ti(OBu)3(OR) + HOR → Ti(OBu)2(OR)2 \+ HOBu etc. For this reason, titanium butoxide is not compatible with alcohol solvents. Analogous to the alkoxide exchange, titanium butoxide hydrolyzes readily. The reaction details are complex, but can be summarized with this balanced equation.
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The complex is prepared by treating [Pt(NH3)4]Cl2 with hydrochloric acid. Many of the reactions of this complex can be explained by the trans effect. It slowly hydrolyzes in aqueous solution to give the mixed aquo complex trans-[PtCl(H2O)(NH3)2]Cl. Similarly it reacts with thiourea (tu) to give colorless trans-[Pt(tu)2(NH3)2]Cl2.
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Group XV phospholipase A2 is an enzyme that in humans is encoded by the PLA2G15 gene. Lysophospholipases are enzymes that act on biological membranes to regulate the multifunctional lysophospholipids. The protein encoded by this gene hydrolyzes lysophosphatidylcholine to glycerophosphorylcholine and a free fatty acid. This enzyme is present in the plasma and thought to be associated with high-density lipoprotein.
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The gene MIPEP encodes one metalloprotease that hydrolyzes peptide fragment of eight amino acids in lengths to process mitochondria-targeted proteins. The human gene MIPEP has 21 Exons and locates at chromosome band13q12. Evidences showed that the human gene MIPEP is highly expressed in the heart, skeletal muscle, and pancreas, three organ systems that are frequently reported with OXPHOS disorders.
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After the pre-RC is formed it must be activated and the replisome assembled in order for DNA replication to occur. In prokaryotes, DnaA hydrolyzes ATP in order to unwind DNA at the oriC. This denatured region is accessible to the DnaB helicase and DnaC helicase loader. Single-strand binding proteins stabilize the newly formed replication bubble and interact with the DnaG primase.
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Hexaethyl tetraphosphate readily hydrolyzes to nontoxic products. Since the material has not been obtained in pure form, the properties remain unverified. Hexaethyl tetraphosphate does not noticeably corrode metals such as brass and iron. However, when a small amount of water is added to the chemical, it forms a strong acid and quickly corrodes galvanized iron and more slowly corrodes pure iron.
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Already the first work on vinylene carbonate describes its bulk polymerization a colorless polymer, which hydrolyzes to a water-soluble product. Subsequent publications suggest that the first authors produced only low molecular weight oligomers.M. Krebs, C. Schneider, Vinylene carbonate – A study of its polymerization and copolymerization behavior, Adv. Chem., 142 (9), 92–98 (1975), doi:10.1021/ba-1975-0142.ch009.
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A box of Pulmozyme Dornase alfa (proprietary name Pulmozyme from Genentech) is a highly purified solution of recombinant human deoxyribonuclease I (rhDNase), an enzyme which selectively cleaves DNA. Dornase alfa hydrolyzes the DNA present in sputum/mucus of cystic fibrosis patients and reduces viscosity in the lungs, promoting improved clearance of secretions. This protein therapeutic agent is produced in Chinese hamster ovary cells.
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AKAPs bind many other signaling proteins, creating a very efficient signaling hub at a certain location within the cell. For example, an AKAP located near the nucleus of a heart muscle cell would bind both PKA and phosphodiesterase (hydrolyzes cAMP), which allows the cell to limit the productivity of PKA, since the catalytic subunit is activated once cAMP binds to the regulatory subunits.
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Vilsmeier reagent is the active intermediate in the formylation reactions, the Vilsmeier reaction or Vilsmeier-Haack reaction that use mixtures of dimethylformamide and phosphorus oxychloride to generate the Vilsmeier reagent, which in turn attacks a nucleophilic substrate and eventually hydrolyzes to give formyl. It is a source of "O=CH+". Pathway for formation of Vilsmeier reagent and its mode of action.
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Acidic lipases make up 30% of lipid hydrolysis occurring during digestion in the human adult, with gastric lipase contributing the most of the two acidic lipases. In neonates, acidic lipases are much more important, providing up to 50% of total lipolytic activity. Gastric lipase hydrolyzes the ester bonds of triglycerides in the stomach. Fatty acids and diacylglycerols are produced from this reaction.
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Pantetheinase, an intestinal enzyme, then hydrolyzes pantetheine into free pantothenic acid. Free pantothenic acid is absorbed into intestinal cells via a saturable, sodium-dependent active transport system. At high levels of intake, when this mechanism is saturated, some pantothenic acid may also be additionally absorbed via passive diffusion. As a whole, when intake increases 10-fold, absorption rate decreases to 10%.
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Low molecular weight phosphotyrosine protein phosphatase is an enzyme that in humans is encoded by the ACP1 gene. The product of this gene belongs to the phosphotyrosine protein phosphatase family of proteins. It functions as an acid phosphatase and a protein tyrosine phosphatase by hydrolyzing protein tyrosine phosphate to protein tyrosine and orthophosphate. This enzyme also hydrolyzes orthophosphoric monoesters to alcohol and orthophosphate.
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Germanium monosulfide or Germanium(II) sulfide is the chemical compound with the formula GeS. It is a chalcogenide glass and a semiconductor. Germanium sulfide is described as a red-brown powder or black crystals. Germanium(II) sulfide when dry is stable in air, hydrolyzes slowly in moist air but rapidly reacts in water forming Ge(OH)2 and then GeO.
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Aldurazyme is the name of the commercialized variant of the enzyme iduronidase, which hydrolyzes the alpha-L-iduronic acid residues of dermatan sulfate and heparin sulfate. Produced in Chinese hamster ovaries by recombinant DNA technology, Aldurazyme is the manufactured by BioMarin Pharmaceutical Inc. and distributed by Genzyme Corporation (a subsidiary of Sanofi). Aldurazyme is administered as a slow intravenous infusion.
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The combined structure of XPO5, RanGTP, and pre-miRNA is known as the ternary complex. Once the ternary complex is formed, it diffuses through a nuclear pore complex into the cytoplasm, transporting pre-miRNA into the cytoplasm in the process. Once in the cytoplasm, RanGAP hydrolyzes GTP to GDP, causing a conformational change that releases the pre-miRNA into the cytoplasm.
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The ParM monomer unit is non-functional before binding a GTP nucleotide. Once the GTP has been bound it can attach to the end of a growing filament. At some point after attachment the ParM hydrolyzes GTP which becomes GDP and remains in the ParM subunit as long as the polymer strand remains intact. ParM forms a left-handed helix structure.
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Acetyl bromide is an acyl bromide compound. As is expected, it may be prepared by reaction between phosphorus tribromide and acetic acid: : 3 CH3COOH + PBr3 → 3 CH3COBr + H3PO3 As usual for an acid halide, acetyl bromide hydrolyzes rapidly in water, forming acetic acid and hydrobromic acid. It also reacts with alcohols and amines to produce acetate esters and acetamides, respectively.
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Unlike tissue carnosinase, serum carnosinase also hydrolyzes the GABA metabolite homocarnosine. Homocarnosinosis, a neurological disorder resulting in an excess of homocarnosine in the brain, though unaffected by tissue carnosinase, is caused by a deficiency of serum carnosinase in its ability to hydrolyze homocarnosine. A deficiency of tissue and serum carnosinase, with serum being an indicator, is the underlying metabolic cause of carnosinemia.
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Water free chloroacetaldehyde is prepared from the hydrate by azeotropic distillation with chloroform, toluene or carbon tetrachloride. Anhydrous chloroacetaldehyde reversibly converts to polyacetals. Less reactive chloroacetaldehyde derivatives might be used instead to obtain chloroacetaldehyde or bypass its intermediate formation completely: e.g. chloroacetaldehyde dimethyl acetal (2-chloro-1,1-dimethoxyethane) hydrolyzes in acidic conditions to give chloroacetaldehyde, which may then quickly react with the other reagents instead of polymerizing.
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Actin is an ATPase, which means that it is an enzyme that hydrolyzes ATP. This group of enzymes is characterised by their slow reaction rates. It is known that this ATPase is “active”, that is, its speed increases by some 40,000 times when the actin forms part of a filament. A reference value for this rate of hydrolysis under ideal conditions is around 0.3 s−1.
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Neutral cholesterol ester hydrolase 1 (NCEH) also known as arylacetamide deacetylase-like 1 (AADACL1) or KIAA1363 is an enzyme that in humans is encoded by the NCEH1 gene. NCEH is an enzyme located in the endoplasmic reticulum. NCEH hydrolyzes 2-acetyl monoalkylglycerol ether, as part of an enzymatic pathway regulating the levels of platelet activating factor and lysophospholipids that may be involved in cancer development.
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Gift JS, McGaughy R, Singh DV, Sonawane B. (2008)Health assessment of phosgene: approaches for derivation of reference concentration. Regul Toxicol Pharmacol. 51:98-107 Furthermore, when phosgene hydrolyzes it forms hydrochloric acid, which can damage the cell surface and cause cell death in the alveoli and bronchioles. The hydrochloric acid triggers an inflammatory response that attracts neutrophils to the lungs, which causes pulmonary edema.
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This solution is costly in refrigeration energy and can negatively affect the organoleptic qualities of the wine. Another solution is to introduce Metatartaric acid, a tartaric acid polymer, into the wine. Its mode of action is still unknown but it prevents microscopic crystals from growing. However, the effect is not sustainable in the long term (between 6 and 18 months) because it hydrolyzes when warm.
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The mRNA decapping complex is a protein complex in eukaryotic cells responsible for removal of the 5' cap. The active enzyme of the decapping complex is the bilobed Nudix family enzyme Dcp2, which hydrolyzes 5' cap and releases 7mGDP and a 5'-monophosphorylated mRNA. This decapped mRNA is inhibited for translation and will be degraded by exonucleases. The core decapping complex is conserved in eukaryotes.
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The toxicity of prunasin is based in its degradation products: (R)-prunasin is hydrolyzed to form benzaldehyde and hydrogen cyanide, which causes toxicity. Plants containing prunasin may therefore be toxic to animals, particularly ruminants. To degrade amygdalin to prunasin, amygdalin beta-glucosidase hydrolyzes the disaccharide to produce (R)-prunasin and D-glucose. Then, prunasin beta-glucosidase uses (R)-prunasin and water to produce D-glucose and mandelonitrile.
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Azathioprine is a thiopurine linked to a second heterocycle (an imidazole derivative) via a thioether. It is a pale yellow solid with a slightly bitter taste and a melting point of 238–245°C. It is practically insoluble in water and only slightly soluble in lipophilic solvents such as chloroform, ethanol, and diethylether. It dissolves in alkaline aqueous solutions, where it hydrolyzes to 6-mercaptopurine.
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The enzyme hydrolyzes the urea to form carbonate and ammonia. During this hydrolysis, a few more spontaneous reactions are performed. Carbamate is hydrolyzed to carbonic acid and ammonia and then further hydrolyzed to ammonium and bicarbonate. This process causes the pH of the reaction to increase 1-2 pH, making the environment more basic which promotes the conditions that this specific bacterium thrives in.
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23.4) is an aspartic protease that specifically hydrolyzes the peptide bond in Phe105-Met106 of κ-casein, and is considered to be the most efficient protease for the cheese-making industry (Rao et al., 1998). British terminology, on the other hand, uses the term caseinogen for the uncoagulated protein and casein for the coagulated protein. As it exists in milk, it is a salt of calcium.
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Beta-D-glucopyranosyl abscisate beta-glucosidase (, AtBG1, ABA-beta-D- glucosidase, ABA-specific beta-glucosidase, ABA-GE hydrolase, beta-D- glucopyranosyl abscisate hydrolase) is an enzyme with systematic name beta-D- glucopyranosyl abscisate glucohydrolase. This enzyme catalyses the following chemical reaction : D-glucopyranosyl abscisate + H2O \rightleftharpoons D-glucose + abscisate The enzyme hydrolyzes the biologically inactive beta-D- glucopyranosyl ester of abscisic acid to produce active abscisate.
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That biosynthesic pathway occurs primarily through a phenolic coupling reaction involving the intermediate isoandrocymbine. The resulting molecule undergoes O-methylation directed by S-adenosylmethionine. Two oxidation steps followed by the cleavage of the cyclopropane ring leads to the formation of the tropolone ring contained by N-formyldemecolcine. N-formyldemecolcine hydrolyzes then to generate the molecule demecolcine, which also goes through an oxidative demethylation that generates deacetylcolchicine.
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Endothelial lipase (LIPG) is a form of lipase secreted by vascular endothelial cells in tissues with high metabolic rates and vascularization, such as the liver, lung, kidney, and thyroid gland. The LIPG enzyme is a vital component to many biological process. These processes include lipoprotein metabolism, cytokine expression, and lipid composition in cells. Unlike the lipases that hydrolyze Triglycerides, endothelial lipase primarily hydrolyzes phospholipids.
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The influx of Ca2+ inside the cell triggers negative feedback mechanisms to suppress TRPV6 activity and prevent Ca2+ overload. TRPV6 channel activity is regulated by the intracellular level of phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2) and interactions with Ca2+-Calmodulin (CaM) complex. The depletion of PIP2 or CaM-binding inactivates TRPV6. The influx of Ca2+ in TRPV6 expressing cells activates phospholipase C (PLC) which in turn hydrolyzes PIP2.
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Methylborane hydrolyzes to methylboronic acid: :(MeBH2)2 \+ 4 H2O → CH3B(OH)2 \+ 4 H2 Symmetrical dimethyldiborane reacts with trimethylamine to yield a solid adduct trimethylamine-methylborane (CH3)3N·BH2CH3. When dimethyldiborane is combined with ammonia and heated, B-methyl borazoles are produced. These borazoles can have one, two or three methyl groups substituted on the boron atoms. Under normal conditions dimethyldiborane does not react with hydrogen.
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The physical characteristics of decaborane(14) resemble those of naphthalene and anthracene, all three of which are volatile colorless solids. Sublimation is the common method of purification. Decaborane is highly flammable, but, like other boron hydrides, it burns with a bright green flame. It is not sensitive to moist air, although it hydrolyzes in boiling water, releasing hydrogen and giving a solution of boric acid.
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It also hydrolyzes the proteins such as those found in hair which may block water pipes. These reactions are sped by the heat generated when sodium hydroxide and the other chemical components of the cleaner dissolve in water. Such alkaline drain cleaners and their acidic versions are highly corrosive and should be handled with great caution. Sodium hydroxide is used in some relaxers to straighten hair.
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It is prepared from acetic anhydride and dinitrogen pentoxide or with nitric acid: :(CH3CO)2O + HNO3 → CH3C(O)ONO2 \+ CH3CO2H It hydrolyzes in air to acetic and nitric acid, the reverse of the above reaction. Alternatively, nitric acid adds to ketene. It is used for some nitrations and nitrolysis reactions.Louw, Robert "Acetyl nitrate" e-EROS Encyclopedia of Reagents for Organic Synthesis 2001, 1-2.
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As stated above, ethiofencarb is stable in acidic conditions, but hydrolyzes when in the presence of a base. It was found to rapidly hydrolyze at pH conditions of 9 and 12. When subjected to sunlight, the main products that resulted from photodegredation are 2-hydroxybenzaldehyde and 3-methylbenzo[e-1,3]oxazine-2-4-dione. The main reaction to occur is the precession of ethiofencarb to its sulfide.
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PLC-γ2 is then phosphorylated by Syk on one site and Btk on two sites. PLC-γ2 then competes with PI-3K for PIP2 which it hydrolyzes into IP3 (inositol 1,4,5-trisphosphate), which ultimately raises intercellular calcium, and diacylglycerol (DAG), which activates portions of the PKC family. Because PLC-γ2 competes for PIP2 with the original signaling molecule PI3K, it serves as a negative feedback mechanism.
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It has long been known plants expend energy to actively take up and concentrate mineral ions. Proton pump hydrolyzes adenosine triphosphate (ATP) to transport H+ ions out of cell; this sets up an electrochemical gradient that causes positive ions to flow into cells. Negative ions are carried across the plasma membrane in conjunction with H+ ions as H+ ions diffuse down their concentration gradient.
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Sodium peroxide hydrolyzes to give sodium hydroxide and hydrogen peroxide according to the reaction : Na2O2 \+ 2 H2O → 2 NaOH + H2O2 Sodium peroxide was used to bleach wood pulp for the production of paper and textiles. Presently it is mainly used for specialized laboratory operations, e.g., the extraction of minerals from various ores. Sodium peroxide may go by the commercial names of Solozone and Flocool.
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P-type ATPases have a single catalytic subunit of 70 - 140 kDa. The catalytic subunit hydrolyzes ATP, contains the aspartyl phosphorylation site and binding sites for the transported ligand(s) and catalyzes ion transport. Various subfamilies of P-type ATPases also need additional subunits for proper function. Additional subunits that lack catalytic activity are present in the ATPase complexes of P1A, P2A, P2C and P4 ATPases. E.g.
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Raffinose is a trisaccharide composed of galactose, glucose, and fructose. It can be found in beans, cabbage, brussels sprouts, broccoli, asparagus, other vegetables, and whole grains. Raffinose can be hydrolyzed to D-galactose and sucrose by the enzyme α-galactosidase (α-GAL), an enzyme not found in the human digestive tract. α-GAL also hydrolyzes other α-galactosides such as stachyose, verbascose, and galactinol, if present.
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Structure of HfCl4(thf)2. The compound hydrolyzes, evolving hydrogen chloride: :HfCl4 \+ H2O → HfOCl2 \+ 2 HCl Aged samples thus often are contaminated with oxychlorides, which are also colourless. THF forms a monomeric 2:1 complex: :HfCl4 \+ 2 OC4H8 → HfCl4(OC4H8)2 Because this complex is soluble in organic solvents, it is a useful reagent for preparing other complexes of hafnium. HfCl4 undergoes salt metathesis with Grignard reagents.
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Titanium tetrachloride (FM) is a colorless, non-flammable, corrosive liquid. In contact with damp air it hydrolyzes readily, resulting in a dense white smoke consisting of droplets of hydrochloric acid and particles of titanium oxychloride. The titanium tetrachloride smoke is irritant and unpleasant to breathe. It is dispensed from aircraft to create vertical smoke curtains, and during World War II it was a favorite smoke generation agent on warships.
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Dynein heavy chain 9, axonemal is a protein that in humans is encoded by the DNAH9 gene. This gene encodes the heavy chain subunit of axonemal dynein, a large multi-subunit molecular motor. Axonemal dynein attaches to microtubules and hydrolyzes ATP to mediate the movement of cilia and flagella. The gene expresses at least two transcript variants; additional variants have been described, but their full length nature has not been determined.
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Titanium bis(acetylacetonate)dichloride is the coordination complex with the formula Ti(C5H7O2)2Cl2. It is a common acetylacetonate complex of titanium. It is a red-orange solid that hydrolyzes slowly in air. The complex is prepared by treatment of titanium tetrachloride with excess acetylacetone: :TiCl4 \+ 2 Hacac → Ti(acac)2Cl2 \+ 2 HCl It is an octahedral complex that crystallizes as a racemic mixture of the chiral cis isomers.
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PDE4 hydrolyzes cyclic adenosine monophosphate (cAMP) to inactive adenosine monophosphate (AMP). Inhibition of PDE4 blocks hydrolysis of cAMP thereby increasing levels of cAMP within cells. cAMP suppresses the activity of immune and inflammatory cells. PDE4 inhibition in an induced chronic lung disease murine model was shown to have anti-inflammatory properties, attenuate pulmonary fibrin deposition and vascular alveolar leakage, and prolong survival in hyperoxia- induced neonatal lung injury.
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Caprolactam is an irritant and is mildly toxic, with an of 1.1 g/kg (rat, oral). In 1991, it was included on the list of hazardous air pollutants by the U.S. Clean Air Act of 1990. It was subsequently removed from the list in 1996 at the request of the manufacturers.EPA - Modifications To The 112(b)1 Hazardous Air Pollutants In water, caprolactam hydrolyzes to aminocaproic acid, which is used medicinally.
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When this is achieved the CALB enzyme selectively hydrolyzes the (R) substrate because of the low binding affinity for the (S) substrate. This gives almost exclusively the (R) allylic alcohol in 98% ee. To expand on this chemistry, Bäckvall designed a one-pot, two- reaction system that utilizes the stereochemical outcome of a DKR reaction to undergo a second energetically favorable reaction with high enantioselectivity. Tandem DKR-intramolecular Diels-Alder reaction.
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Itaconic anhydride is a colourless, crystalline solid which dissolves in many polar organic solvents and hydrolyzes with water forming itaconic acid. The substance is recommended to be stored in a dry and inert atmosphere. At temperatures above its melting point, itaconic anhydride is converted to citraconic anhydride. Even at significantly lower temperatures, such as in boiling chloroform, this isomerization can take place in the presence of tertiary amines.
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Here it is converted into glycerol 3-phosphate by the action of glycerol kinase which hydrolyzes one molecule of ATP per glycerol molecule which is phosphorylated. Glycerol 3-phosphate is then oxidized to dihydroxyacetone phosphate, which is, in turn, converted into glyceraldehyde 3-phosphate by the enzyme triose phosphate isomerase. From here the three carbon atoms of the original glycerol can be oxidized via glycolysis, or converted to glucose via gluconeogenesis.
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Terbium(IV) fluoride hydrolyzes quickly in hot water, producing terbium(III) fluoride and terbium oxyfluoride (TbOF). Heating terbium(IV) fluoride will cause it to decompose into terbium(III) fluoride and fluorine gas. : 2 TbF4 → 2 TbF3 \+ F2↑ The reaction will produce the mixed valence compound Tb(TbF5)3, which has the same crystal form as Ln(HfF5)3.Nikulin V V, Goryachenkov S A, Korobov M V, et al.
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DBNPA or 2,2-dibromo-3-nitrilopropionamide is a quick-kill biocide that easily hydrolyzes under both acidic and alkaline conditions. It is preferred for its instability in water as it quickly kills and then quickly degrades to form a number of products, depending on the conditions, including ammonia, bromide ions, dibromoacetonitrile, and dibromoacetic acid. DBNPA acts similar to the typical halogen biocides. DBNPA is used in a wide variety of applications.
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PSCl3 is soluble in benzene, carbon tetrachloride, chloroform, and carbon disulfide. However, it hydrolyzes rapidly in basic or hydroxylic solutions, such as alcohols and amines, to produce thiophosphates. In water PSCl3 reacts, and contingent on the reaction conditions, produces either phosphoric acid, hydrogen sulfide, and hydrochloric acid or dichlorothiophosphoric acid and hydrochloric acid.Fee, D. C.; Gard, D. R.; Yang, C. “Phosphorus Compounds” Kirk-Othmer Encyclopedia of Chemical Technology.
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RNase H-dependent oligonucleotides cause the target mRNA molecules to be degraded, while steric-blocker oligonucleotides prevent translation of the mRNA molecule. The majority of antisense drugs function through the RNase H-dependent mechanism, in which RNase H hydrolyzes the RNA strand of the DNA/RNA heteroduplex. This mechanism is thought to be more efficient, resulting in an approximately 80% to 95% decrease in the protein and mRNA expression.
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A. carneus contributes to both medicine and industry, often simultaneously. The fungus produces a unique alkaline lipase (Aspergillus carneus lipase) with high pH and temperature tolerance, 1,3-regioselectivity, stability in organic solvents and esterification and transesterification properties. The lipase hydrolyzes a variety of oils and triglycerides, most notably sunflower oil. It is also extracellular, which improves yield during purification, and is resistant to inhibition by sodium propionate, a common food preservative.
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DUTP pyrophosphatase, also known as DUT, is an enzyme which in humans is encoded by the DUT gene on chromosome 15. This gene encodes an essential enzyme of nucleotide metabolism. The encoded protein forms a ubiquitous, homotrimeric enzyme that hydrolyzes dUTP to dUMP and pyrophosphate. This reaction serves two cellular purposes: providing a precursor (dUMP) for the synthesis of thymine nucleotides needed for DNA replication, and limiting intracellular pools of dUTP.
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Trypsin () is a serine protease from the PA clan superfamily, found in the digestive system of many vertebrates, where it hydrolyzes proteins.The German physiologist Wilhelm Kühne (1837-1900) discovered trypsin in 1876. See: Trypsin is formed in the small intestine when its proenzyme form, the trypsinogen produced by the pancreas, is activated. Trypsin cuts peptide chains mainly at the carboxyl side of the amino acids lysine or arginine.
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Carnosinase in humans has two forms: 1\. Cellular, or tissue carnosinase: This form of the enzyme is found in every bodily tissue. It is a dimer, and hydrolyzes both carnosine and anserine, preferring dipeptides that have a histidine monomer in the C-terminus position. Tissue carnosinase is often considered a "nonspecific dipeptidase", based in part on its ability to hydrolyze a range of dipeptide substrates, including those belonging to prolinase. 2\.
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Expression of holin S at a precisely scheduled time after phage infection terminates respiration and allows release of a muralytic enzyme, endolysin, that hydrolyzes the cell wall. Point mutations in the S gene that prevent lethality alter TMSs 1 and 2 and the connecting loop. TMS 2 is particularly important for function. A three-step mechanism (monomer → dimer → oligomeric pore) has been proposed for assembly of the pore.
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5' cap structure Capping is a three-step process that utilizes the enzymes RNA triphosphatase, guanylyltransferase, and methyltransferase. Through a series of three steps, the cap is added to the first nucleotide's 5' hydroxyl group of the growing mRNA strand while transcription is still occurring. First, RNA 5' triphosphatase hydrolyzes the 5' triphosphate group to make diphospate-RNA. Then, the addition of GMP by guanylyltransferase produces the guanosine cap.
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Structure of the carbapenem backbone. Carbapenems are a class of beta-lactam antibiotics that are capable of killing most bacteria by inhibiting the synthesis of one of their cell wall layers. The carbapenems were developed to overcome antibiotic resistance mediated by bacterial beta-lactamase enzymes. However, the blaNDM-1 gene produces NDM-1, which is a carbapenemase beta-lactamase - an enzyme that hydrolyzes and inactivates these carbapenem antibiotics.
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The pit contains a high concentration of metal (Me) chloride (MeCln) which hydrolyzes with water to produce the corresponding metal hydroxide (Me(OH)n), and n H+ and n Cl– ions, accelerating the corrosion process. In the pit, the oxygen concentration is essentially zero and all of the cathodic oxygen reactions take place on the metal surface outside the pit. The pit is anodic and the locus of rapid dissolution of the metal.princeton.edu, pitcorrosion.
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AChe mechanism of action AChE is a hydrolase that hydrolyzes choline esters. It has a very high catalytic activity—each molecule of AChE degrades about 25,000 molecules of acetylcholine (ACh) per second, approaching the limit allowed by diffusion of the substrate. The active site of AChE comprises 2 subsites—the anionic site and the esteratic subsite. The structure and mechanism of action of AChE have been elucidated from the crystal structure of the enzyme.
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Triphenylmethyl hexafluorophosphate readily hydrolyzes, in a reaction that is the reverse of one of its syntheses: :(C6H5)3CPF6 \+ H2O → (C6H5)3COH + HPF6 Triphenylmethyl hexafluorophosphate has been used for abstracting hydride () from organic compounds. Treatment of metal-alkene and diene complexes one can generate allyl and pentadienyl complexes, respectively. Triphenylmethyl perchlorate is a common substitute for triphenylmethyl hexafluorophosphate. However, the perchlorate is not used as widely, because, like other organic perchlorates, it is potentially explosive.
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When rhodopsin (Rh) absorbs a photon of light its chromophore, 11-cis-3-hydroxyretinal, is isomerized to all-trans-3-hydroxyretinal. Rh undergoes a conformational change into its active form, metarhodopsin. Metarhodopsin activates Gq, which in turn activates a phospholipase Cβ (PLCβ) known as NorpA. PLCβ hydrolyzes phosphatidylinositol (4,5)-bisphosphate (PIP2), a phospholipid found in the cell membrane, into soluble inositol triphosphate (IP3) and diacylglycerol (DAG), which stays in the cell membrane.
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Potassium dimanganate(III), K6Mn2O6, is a manganese(III) compound. Unlike lithium and sodium manganites, MMnO2, which are best described as mixed oxides, potassium dimanganite contains discrete Mn2O anions in the solid state.. It rapidly hydrolyzes in air. K6Mn2O6 is prepared as ruby-red crystals by the reaction of excess potassium oxide with manganese(II) oxide in a sealed nickel bomb at 610 °C for ten days. The Mn2O anion has an Al2Cl6-type structure.
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This gene encodes a purine- converting ectoenzyme which belongs to the ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) family. The encoded protein hydrolyzes extracellular nucleoside triphosphates (UTP, GTP, and CTP) to nucleoside monophosphates as part of a purinergic signaling pathway. It contains two transmembrane domains at the N- and C-termini and a large, hydrophobic catalytic domain located in between. This gene affects oxidative stress as well as DNA damage and is a mediator of senescence.
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Sodium borohydride, also known as sodium tetrahydridoborate and sodium tetrahydroborate, is an inorganic compound with the formula NaBH4. This white solid, usually encountered as a powder, is a reducing agent that finds application in chemistry, both in the laboratory and on an industrial scale. It has been tested as pretreatment for pulping of wood, but is too costly to be commercialized. The compound is soluble in alcohols, certain ethers, and water, although it slowly hydrolyzes.
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It can also be formed by the deamination of adenosine monophosphate by AMP deaminase. It can be hydrolysed to inosine. The enzyme deoxyribonucleoside triphosphate pyrophosphohydrolase, encoded by YJR069C in Saccharomyces cerevisiae and containing (d)ITPase and (d)XTPase activities, hydrolyzes inosine triphosphate (ITP) releasing pyrophosphate and IMP. Important derivatives of inosinic acid include the purine nucleotides found in nucleic acids and adenosine triphosphate, which is used to store chemical energy in muscle and other tissues.
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Histidine triad nucleotide-binding protein 1 also known as adenosine 5'-monophosphoramidase is an enzyme that in humans is encoded by the HINT1 gene. HINT1 hydrolyzes purine nucleotide phosphoramidates with a single phosphate group. In addition, functions as scaffolding protein that modulates transcriptional activation. It is a haploinsufficient tumor suppressor gene that inhibits the Wnt/β-catenin pathway in colon cancer cells and microphthalmia-associated transcription factor (MITF) activity in human mast cells.
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The PDE5 enzyme is specific for cGMP which means it only hydrolyzes cGMP but not cAMP. The selectivity is mediated through an intricate network of hydrogen bonding which is favorable for cGMP but unfavorable for cAMP in PDE5. By inhibition of PDE5 enzyme the cGMP concentration will be raised and can therefore increase the relaxation of smooth muscles. PDE5 has only one subtype, PDE5A, of which there are 4 isoforms in humans called PDE5A1-4.
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Indican readily hydrolyzes to release β-D-glucose and indoxyl. Oxidation by exposure to air converts indoxyl to indigotin, the insoluble blue chemical that is the endpoint of indigo dye. Indican was obtained from the processing of the plant's leaves, which contain as much as 0.2–0.8% of this compound. The leaves were soaked in water and fermented to convert the glycoside indican present in the plant to the blue dye indigotin.
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Phospholipase D (, lipophosphodiesterase II, lecithinase D, choline phosphatase) (PLD) is an enzyme of the phospholipase superfamily. Phospholipases occur widely, and can be found in a wide range of organisms, including bacteria, yeast, plants, animals, and viruses. Phospholipase D’s principal substrate is phosphatidylcholine, which it hydrolyzes to produce the signal molecule phosphatidic acid (PA), and soluble choline. Plants contain numerous genes that encode various PLD isoenzymes, with molecular weights ranging from 90-125 kDa.
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Methyl benzoate can be isolated from the freshwater fern Salvinia molesta. It is one of many compounds that is attractive to males of various species of orchid bees, which apparently gather the chemical to synthesize pheromones; it is commonly used as bait to attract and collect these bees for study. Cocaine hydrochloride hydrolyzes in moist air to give methyl benzoate; drug-sniffing dogs are thus trained to detect the smell of methyl benzoate.
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Lactoferrin hydrolyzes RNA and exhibits the properties of pyrimidine-specific secretory ribonucleases. In particular, by destroying the RNA genome, milk RNase inhibits reverse transcription of retroviruses that cause breast cancer in mice. Parsi women in West India have the milk RNase level markedly lower than in other groups, and their breast cancer rate is three times higher than average. Thus, ribonucleases of milk, and lactoferrin in particular, might play an important role in pathogenesis.
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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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The highest known ruthenium halide is the hexafluoride, a dark brown solid that melts at 54 °C. It hydrolyzes violently upon contact with water and easily disproportionates to form a mixture of lower ruthenium fluorides, releasing fluorine gas. Ruthenium pentafluoride is a tetrameric dark green solid that is also readily hydrolyzed, melting at 86.5 °C. The yellow ruthenium tetrafluoride is probably also polymeric and can be formed by reducing the pentafluoride with iodine.
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Although BF4− has high ionic mobility, solutions of its Li+ salt are less conductive than other less associated salts. As an electrolyte in lithium-ion batteries, LiBF4 offers some advantages relative to the more common LiPF6. It exhibits greater thermal stability and moisture tolerance. For example, LiBF4 can tolerate a moisture content up to 620 ppm at room temperature whereas LiPF6 readily hydrolyzes into toxic POF3 and HF gases, often destroying the battery's electrode materials.
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Pancreatic lipase, also known as pancreatic triacylglycerol lipase or steapsin, is an enzyme secreted from the pancreas. As the primary lipase enzyme that hydrolyzes (breaks down) dietary fat molecules in the human digestive system, it is one of the main digestive enzymes, converting triglyceride substrates like 1 found in ingested oils to monoglycerides 3 and free fatty acids 2a and 2b.Peter Nuhn: Naturstoffchemie, S. Hirzel Wissenschaftliche Verlagsgesellschaft, Stuttgart, 2. Auflage, 1990, S. 308−309, .
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In vitro the ParM monomer has been observed polymerizing both with ATP and with GTP, but experiments by Popp et al. seem to indicate that the reaction "prefers" GTP and that GTP is the nucleotide that most likely makes the significant contributions in the cell. For the remainder of this article GTP will be assumed to be the active nucleotide although many experiments have used ATP instead. ParM binds and hydrolyzes GTP as it polymerizes.
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Sodium methoxide is prepared by treating methanol with sodium: :2 Na + 2 → 2 + The reaction is so exothermic that ignition is possible. The resulting solution, which is colorless, is often used as a source of sodium methoxide, but the pure material can be isolated by evaporation followed by heating to remove residual methanol. The solid hydrolyzes in water to give methanol and sodium hydroxide. Indeed, samples of sodium methoxide are often contaminated with sodium hydroxide.
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The product of light activation, Metarhodopsin II, initiates the visual phototransduction pathway by stimulating the G protein transducin (Gt), resulting in the liberation of its α subunit. This GTP-bound subunit in turn activates cGMP phosphodiesterase. cGMP phosphodiesterase hydrolyzes (breaks down) cGMP, lowering its local concentration so it can no longer activate cGMP-dependent cation channels. This leads to the hyperpolarization of photoreceptor cells, changing the rate at which they release transmitters.
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ADP-ribose hydrolases in general act as protective agents against excessive intracellular accumulation of ADP-ribose, as high intracellular levels of ADP-ribose can be damaging to the cell. ADP-ribose diphosphatase, in particular, hydrolyzes ADP-ribose into AMP and D-ribose 5-phosphate, both of which are intermediates of central metabolic pathways and therefore are easily reused. Other common names for ADP-ribose diphosphatase include ADP-ribose pyrophosphatase and ADPRase. ADP-ribose is commonly referred to as ADPR.
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The chloride from the hydrochloric acid in sodium chloride does not hydrolyze, though, so sodium chloride is not basic. The difference between a basic salt and an alkali is that an alkali is the soluble hydroxide compound of an alkali metal or an alkaline earth metal. A basic salt is any salt that hydrolyzes to form a basic solution. Another definition of a basic salt would be a salt that contains amounts of both hydroxide and other anions.
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Nitrogen concentration of cattle urine varies between approximately 3.0 and 10.5 g/L. Although many nitrogenous constituents are involved in the chemical make-up of cattle urine, urea is dominant. Urea concentration represents 52.0% to 93.5% of total urinary nitrogen and is dependent upon the amount of dietary protein consumed by cattle. Through a process known as ureolysis, the enzyme urease completely hydrolyzes urea to ammonia within one to two days of being excreted and soaked into soils.
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Interest in this highly corrosive compound began in the fifties when there were extensive studies of its physicochemical properties. It is a powerful fluorinating and oxidizing agent. It oxidizes elemental sulfur to sulfur tetrafluoride:. :S + 4 VF5 → 4 VF4 \+ SF4 Like other electrophilic metal halides, it hydrolyzes, first to the oxyhalide: :VF5 \+ H2O → VOF3 \+ 2 HF Then to the binary oxide: :2 VOF3 \+ 3 H2O → V2O5 \+ 6 HF Hydrolysis is accelerated in the presence of base.
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Even though enamines are more nucleophilic than their enol counterparts, they can still react selectively, rendering them useful for alkylation reactions. The enamine nucleophile can attack haloalkanes to form the alkylated iminium salt intermediate which then hydrolyzes to regenerate a ketone (a starting material in enamine synthesis). This reaction was pioneered by Gilbert Stork, and is sometimes referred to by the name of its inventor. Analogously, this reaction can be used as an effective means of acylation.
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The bulk low concentration of PA combined with high local bursts is the opposite of PIP2 signaling. PIP2 is kept relatively high in the membrane and then transiently hydrolized near a protein in order to transiently reduce PIP2 signaling. PA signaling mirrors PIP2 signaling in that the bulk concentration of signaling lipid need not change to exert a potent local effect on a target protein. As described above, PLD hydrolyzes PC to form PA and choline.
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This gene encodes the puromycin-sensitive aminopeptidase, a zinc metallopeptidase which hydrolyzes amino acids from the N-terminus of its substrate. The protein has been localized to both the cytoplasm and to cellular membranes. This enzyme degrades enkephalins in the brain, and studies in mouse suggest that it is involved in proteolytic events regulating the cell cycle. It has been identified as a novel modifier of TAU-induced neurodegeneration with neuroprotective effects via direct proteolysis of TAU protein.
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Polygalacturonase (), also known as pectin depolymerase, PG, pectolase, pectin hydrolase, and poly-alpha-1,4-galacturonide glycanohydrolase, is an enzyme that hydrolyzes the alpha-1,4 glycosidic bonds between galacturonic acid residues. Polygalacturonan, whose major component is galacturonic acid, is a significant carbohydrate component of the pectin network that comprises plant cell walls.Jones, T. M., Anderson, A. J., and Albersheim, P. (1972) Hostpathogen interactions IV, Studies on the polysaccharide-degrading enzymes secreted by Fusarium oxysporum f. sp. lycopersici, Physiol.
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Lipoprotein lipase (LPL) () is a member of the lipase gene family, which includes pancreatic lipase, hepatic lipase, and endothelial lipase. It is a water-soluble enzyme that hydrolyzes triglycerides in lipoproteins, such as those found in chylomicrons and very low-density lipoproteins (VLDL), into two free fatty acids and one monoacylglycerol molecule. It is also involved in promoting the cellular uptake of chylomicron remnants, cholesterol-rich lipoproteins, and free fatty acids. LPL requires ApoC-II as a cofactor.
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Alpha- glucosidase inhibitors are saccharides that act as competitive inhibitors of enzymes needed to digest carbohydrates: specifically alpha-glucosidase enzymes in the brush border of the small intestines. The membrane-bound intestinal alpha-glucosidases hydrolyze oligosaccharides, trisaccharides, and disaccharides to glucose and other monosaccharides in the small intestine. Acarbose also blocks pancreatic alpha-amylase in addition to inhibiting membrane-bound alpha-glucosidases. Pancreatic alpha-amylase hydrolyzes complex starches to oligosaccharides in the lumen of the small intestine.
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Thin filament formation depicting the polymerization mechanism for converting G-actin to F-actin; note the hydrolysis of the ATP. Actin remains one of the most abundant proteins in all of Eukarya and is an enzyme (ATPase) that gradually hydrolyzes ATP. It exists in two forms within eukaryotic cells: globular or G-actin and filament/filamentous or F-actin. Globular actin is the monomeric form of the protein while the filamentous actin is a linear polymer of globular subunits.
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This parameter is commonly expressed as the epoxide number, which is the number of epoxide equivalents in 1 kg of resin (Eq./kg), or as the equivalent weight, which is the weight in grams of resin containing 1 mole equivalent of epoxide (g/mol). Since unsymmetrical epoxides are chiral, the bis epoxide consists of three stereoisomers, although these are not separated. Bisphenol A diglycidyl ether slowly hydrolyzes to 2,2-bis[4(2,3-hydroxypropoxy)phenyl)propane (bis-HPPP).
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Here, arylsulfatase A hydrolyzes the sulfate group. However, in order for this reaction to be carried out, a sphingolipid activator protein such as saposin B must be present. Saposin B extracts sulfatide from the membrane, which makes it accessible to arylsulfatase A. Arylsulfatase A can then hydrolyze the sulfate group. Accumulation of sulfatide can cause metachromatic leukodystrophy, a lysosomal storage disease and may be caused because of a defect in arylsulfatase A, leading to an inability to degrade sulfatide.
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Proteins are targeted for degradation by the proteasome with covalent modification of a lysine residue that requires the coordinated reactions of three enzymes. In the first step, a ubiquitin- activating enzyme (known as E1) hydrolyzes ATP and adenylylates a ubiquitin molecule. This is then transferred to E1's active-site cysteine residue in concert with the adenylylation of a second ubiquitin. This adenylylated ubiquitin is then transferred to a cysteine of a second enzyme, ubiquitin- conjugating enzyme (E2).
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Evidence suggests that cystinosin transports cystine out of lysosomes in a pmf-dependent process. The proton motive force (pmf) across the lysosomal membrane is generated by a V-type ATPase which hydrolyzes cytoplasmic ATP to pump protons into the lysosomal lumen. Removal of the C-terminal GYDQL lysosomal sorting motif causes cystinosin to migrate to the plasma membrane with the intralysosomal face of cystinosin facing the extracellular medium. The cells then take up cystine in a pmf-dependent process.
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A. carneus secretes a low molecular weight xylanase which hydrolyzes heteroxylan, a component of the plant cell wall. The activity of A. carneus xylanase is stable over a broad pH range (3-10), but is optimized at acidic pH and 60 °C. The enzyme is highly specific to low-cost agricultural waste products, particularly corn cobs and coba husks, which it can degrade into xylooligosaccharides. Xylooligosaccharides may be used as food additives, components of animal feed and prebiotics.
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There were eight interactions identified by Mentha. The first one was UFSP2 which hydrolyzes the peptide bond at the C-term gly of UFM1, a ubiquitin-like modifier protein bound to a number of target proteins. The second one was HSCB which acts as a co-chaperone in iron-sulfur cluster assembly in mitochondria. The third was GRB2 which is an adapter protein that provides a critical link between cell surface growth factor receptors and the Ras signaling pathway.
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CSCl2 is prepared in a two-step process from carbon disulfide. In the first step, carbon disulfide is chlorinated to give trichloromethanesulfenyl chloride (perchloromethyl mercaptan), CCl3SCl: ::CS2 \+ 3 Cl2 → CCl3SCl + S2Cl2 The chlorination must be controlled as excess chlorine converts trichloromethanesulfenyl chloride into carbon tetrachloride. Steam distillation separates the trichloromethanesulfenyl chloride, a rare sulfenyl chloride, and hydrolyzes the sulfur monochloride. Reduction of trichloromethanesulfenyl chloride produces thiophosgene: :: CCl3SCl + M → CSCl2 \+ MCl2 Typically, tin is used for the reducing agent M.
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ACE hydrolyzes peptides by the removal of a dipeptide from the C-terminus. Likewise it converts the inactive decapeptide angiotensin I to the octapeptide angiotensin II by removing the dipeptide His- Leu. proposed ACE catalytic mechanism ACE is a central component of the renin–angiotensin system (RAS), which controls blood pressure by regulating the volume of fluids in the body.Schematic diagram of the 375x375px Angiotensin II is a potent vasoconstrictor in a substrate concentration- dependent manner.
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Phosphatidylinositol-glycan-specific phospholipase D is an enzyme that in humans is encoded by the GPLD1 gene. Many proteins are tethered to the extracellular face of eukaryotic plasma membranes by a glycosylphosphatidylinositol (GPI) anchor. The GPI-anchor is a glycolipid found on many blood cells. The protein encoded by the GPLD1 gene is a GPI degrading enzyme that hydrolyzes the inositol phosphate linkage in proteins anchored by phosphatidylinositol glycans, thereby releasing the attached protein from the plasma membrane.
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The rate of reaction can be measured by using the amount of time needed for the milk to turn translucent. Trypsin is commonly used in biological research during proteomics experiments to digest proteins into peptides for mass spectrometry analysis, e.g. in-gel digestion. Trypsin is particularly suited for this, since it has a very well defined specificity, as it hydrolyzes only the peptide bonds in which the carbonyl group is contributed either by an arginine or lysine residue.
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On the other hand, different research has shown that calreticulin may be released from vesicles other than cortical granules. Furthermore, upon exocytosis, this calreticulin interacts with the oocyte's cytoskeleton, thereby allowing the transmission of transmembrane signaling for the continuance of the cell's cycle. N-Acetylglucosaminidase: Experimentally found within mouse cortical granules, N-Acetylglucosaminidase is a glycosidase that hydrolyzes N-acetylglucosamine residues located on the zona pellucida. N-acetylglucosamines on the zona pellucida normally promote sperm binding.
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SbF3 hydrolyzes only partially because of the increasing ionic character of the bond to fluorine. The compounds are weak Lewis bases, with NF3 again being an exception. The pentafluorides of phosphorus and arsenic are much more reactive than their trifluorides; antimony pentafluoride is such a strong acid that it holds the title of the strongest Lewis acid. Nitrogen is not known to form a pentafluoride, although the tetrafluoroammonium cation () features nitrogen in the formal oxidation state of +5.
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Formaldehyde gives the bis(hydroxymethyl)urea, an intermediate in the formation of urea-formaldehyde resins. Cyclic ureas result from glyoxal ((CHO)2): :(H2N)2CO + (CHO)2 → (CH(OH)NH)2CO Two equivalents of urea condense with isobutyraldehyde giving the alkylidene derivative: :2(H2N)2CO + OC(H)CHMe2 → (H2N)C(O)NH]2CHCHMe2 \+ H2O This derivative, isobutylidenediurea, is used as a slow-release fertilizer because in the soil it slowly hydrolyzes, reverting to urea, an excellent source of fixed nitrogen.
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Glycoside hydrolase family 14 CAZY GH_14 comprises enzymes with only one known activity; beta-amylase (). A Glu residue has been proposed as a catalytic residue, but it is not known if it is the nucleophile or the proton donor. Beta-amylase is an enzyme that hydrolyzes 1,4-alpha-glucosidic linkages in starch-type polysaccharide substrates so as to remove successive maltose units from the non-reducing ends of the chains. Beta-amylase is present in certain bacteria as well as in plants.
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Organophosphorus acid anhydrolase (OPAA) is an enzyme that been shown to be particularly effective in detoxifying organophosphorus-containing compounds, such as deadly nerve gas used in chemical warfare. The enzyme is found in a diverse range of organisms, including protozoa, squid and clams, mammals,Little, J. S., C. A. Broomfield, L. J. Boucher, and M. K. Fox-Talbot. 1986. Partial characterization of a rat liver enzyme that hydrolyzes sarin, soman, tabun and DFP. Fed. Proc. 45:791. and soil bacteria.
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Chromyl chloride is often stored in sealed glass ampoules to prevent vapours leaking out of the container CrO2Cl2 hydrolyzes to release hydrochloric acid (HCl) and hexavalent chromium (CrVI) Acute: Exposure to chromyl chloride vapour irritates the respiratory system and severely irritates the eyes, and the liquid burns the skin and eyes. Ingestion would cause severe internal damage. Chronic: CrVI can produce chromosomal aberrations and is a human carcinogen via inhalation. Frequent exposure of the skin to chromyl chloride may result in ulceration.
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Dipeptidyl peptidase 8 is an enzyme that in humans is encoded by the DPP8 gene. This gene encodes a member of the peptidase S9B family, a small family of dipeptidyl peptidases that are able to cleave peptide substrates at a prolyl bond. The encoded protein shares similarity with Dipeptidyl peptidase-4 in that it is ubiquitously expressed, and hydrolyzes the same substrates. These similarities suggest that, like dipeptidyl peptidase IV, this protein may play a role in T-cell activation and immune function.
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A step in the biosynthesis of many α-amino acids is the reductive amination of an α-ketoacid, usually by a transaminase enzyme. The process is catalyzed by pyridoxamine phosphate, which is converted into pyridoxal phosphate after the reaction. The initial step entails formation of an imine, but the hydride equivalents are supplied by a reduced pyridine to give an aldimine, which hydrolyzes to the amine.Nelson, D. L.; Cox, M. M. "Lehninger, Principles of Biochemistry" 3rd Ed. Worth Publishing: New York, 2000. .
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It is the enzymatic activity of the ATPase in the myosin head that cyclically hydrolyzes ATP, fueling the myosin power stroke. This process converts chemical to mechanical energy, and propels shortening of the sarcomeres in order to generate intraventricular pressure and power. An accepted mechanism for this process is that ADP-bound myosin attaches to actin while thrusting tropomyosin inwards, then the S1-S2 myosin lever arm rotates ~70° about the converter domain and drives actin filaments towards the M-line.
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Diazinon is a contact insecticide which kills insects by altering normal neurotransmission within the nervous system of the insect. As mentioned above, diazinon inhibits the enzyme acetylcholinesterase (AChE), which hydrolyzes the neurotransmitter acetylcholine (ACh) in cholinergic synapses and neuromuscular junctions. This results in abnormal accumulation of ACh within the nervous system. Diazinon, although a thiophosphoric ester, shares a common mechanism of toxicity with other organophosphate insecticides such as chlorpyrifos, malathion and parathion, and is not very effective against the organophosphate-resistant insect populations.
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Trypsin, a protease released by pancreatic acinar cells, hydrolyzes CCK- releasing peptide and monitor peptide, in effect turning off the additional signals to secrete CCK. CCK also causes the increased production of hepatic bile, and stimulates the contraction of the gall bladder and the relaxation of the sphincter of Oddi (Glisson's sphincter), resulting in the delivery of bile into the duodenal part of the small intestine. Bile salts form amphipathic lipids, micelles that emulsify fats, aiding in their digestion and absorption.
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Apolipoprotein C2 or apolipoprotein C-II is a protein that in humans is encoded by the APOC2 gene. The protein encoded by this gene is secreted in plasma where it is a component of very low density lipoproteins and chylomicrons. This protein activates the enzyme lipoprotein lipase in capillaries, which hydrolyzes triglycerides and thus provides free fatty acids for cells. Mutations in this gene cause hyperlipoproteinemia type IB, characterized by xanthomas, pancreatitis, and hepatosplenomegaly, but no increased risk for atherosclerosis.
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The protein RF3 releases the Class I release factor so that it may occupy the ribosomal A site. EF-G hydrolyzes GTP and undergoes a large conformational change to push RF3 down the ribosome, which occurs alongside tRNA dissociation and promotes the ribosomal subunit rotation. This motion actively splits the B2a/B2b bridge, which connects the 30S and the 50S subunits, so that the ribosome can split. IF3 then isolates the 30S subunit to prevent re-association of the large and small subunits.
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Phospholipases A2 (PLA2s) are enzymes that cleave fatty acid in position two of phospholipids, hydrolyzing the bond between the second fatty acid “tail” and the glycerol molecule. This particular phospholipase specifically recognizes the sn-2 acyl bond of phospholipids and catalytically hydrolyzes the bond, releasing arachidonic acid and lysophosphatidic acid. Upon downstream modification by cyclooxygenases or lipoxygenases, arachidonic acid is modified into active compounds called eicosanoids. Eicosanoids include prostaglandins and leukotrienes, which are categorized as anti-inflammatory and inflammatory mediators.
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It is a strong Lewis acid and is the main neptunium ion encountered in solutions of pH 3–4. Though stable in acidic solutions, it is quite easily reduced to the Np(V) ion, and it is not as stable as the homologous hexavalent ions of its neighbours uranium and plutonium (the uranyl and plutonyl ions). It hydrolyzes in basic solutions to form the oxo and hydroxo ions NpO2OH+, , and . ;Neptunium(VII) Np(VII) is dark green in a strongly basic solution.
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Angiogenin (Ang) also known as ribonuclease 5 is a small 123 amino acid protein that in humans is encoded by the ANG gene. Angiogenin is a potent stimulator of new blood vessels through the process of angiogenesis. Ang hydrolyzes cellular RNA, resulting in modulated levels of protein synthesis and interacts with DNA causing a promoter-like increase in the expression of rRNA. Ang is associated with cancer and neurological disease through angiogenesis and through activating gene expression that suppresses apoptosis.
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Alkenes can be oxidatively cleaved by ozone, in a process called ozonolysis, giving alcohols, aldehydes, ketones, and carboxylic acids, depending on the second step of the workup. General reaction equation of ozonolysis Ozone can also cleave alkynes to form an acid anhydride or diketone product. If the reaction is performed in the presence of water, the anhydride hydrolyzes to give two carboxylic acids. :450px Usually ozonolysis is carried out in a solution of dichloromethane, at a temperature of −78 °C.
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It is the enzymatic activity of the ATPase in the myosin head that cyclically hydrolyzes ATP, fueling the myosin power stroke. This process converts chemical to mechanical energy, and propels shortening of the sarcomeres in order to generate intraventricular pressure and power. An accepted mechanism for this process is that ADP-bound myosin attaches to actin while thrusting tropomyosin inwards, then the S1-S2 myosin lever arm rotates ~70° about the converter domain and drives actin filaments towards the M-line.
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Varying functions have been described for this protein. It has been described as a lysosomal hyaluronidase which is active at a pH below 4 and specifically hydrolyzes high molecular weight hyaluronan. It has also been described as a GPI-anchored cell surface protein which does not display hyaluronidase activity but does serve as a receptor for the oncogenic virus Jaagsiekte sheep retrovirus. The gene is one of several related genes in a region of chromosome 3p21.3 associated with tumor suppression.
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The MIT domain is responsible for the interaction of Vps4 with the MIM domain of Vps2. The AAA-ATPase domain hydrolyzes ATP to power disassembly of the ESCRT-III complex. This “stripping” of ESCRT-III allows all associated subunits to be recycled for further use. Vta1 is a dimeric protein containing one VSL domain (so named because it is found in the proteins Vps4, SBP1, and LIP5), which enables binding to Vps4, and a MIT domain for associating with ESCRT-III subunit Vps60.
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Bacterial initiation factor 2 binds to an initiator tRNA and controls the entry of that tRNA into the ribosome. IF2, bound to GTP, binds to the 30S P site. After associating with the 30S subunit, fMet-tRNAf binds to the IF2 then IF2 transfers the tRNA into the partial P site. When the 50S subunit joins, it hydrolyzes GTP to GDP and Pi, causing a conformational change in the IF2 that causes IF2 to release and allow the 70S subunit to form.
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Diphosgene serves as a source of two equivalents of phosgene: :2 RNH2 \+ ClCO2CCl3 → 2 RNCO + 4 HCl With α-amino acids diphosgene gives the acid chloride-isocyanates, OCNCHRCOCl, or N-carboxy-amino acid anhydrides depending on the conditions.Kurita, K. "Trichloromethyl Chloroformate" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. . It hydrolyzes to release HCl in humid air. Diphosgene is used in some laboratory preparations because it is easier to handle than phosgene.
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Asparagine endopeptidase (AEP, mammalian legumain, δ-secretase; ) is a proteolytic enzyme from C13 peptidase family which hydrolyses a peptide bond using the thiol group of a cysteine residue as a nucleophile (hence also called cysteine protease). It is also known as asparaginyl endopeptidase, citvac, proteinase B, hemoglobinase, PRSC1 gene product or LGMN (Homo sapiens), vicilin peptidohydrolase and bean endopeptidase. In humans it is encoded by the LGMN gene (previous symbol PRSC1). It hydrolyzes substrates at the C-terminus of asparagine residues.
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Directed overflow is a special case of damage pre-emption, where excess of a normal, but reactive metabolite could lead to toxic products. Preventing this excess is thus pre-emption of potential damage. The first two intermediates in riboflavin biosynthesis are highly reactive and can spontaneously break down to 5-phosphoribosylamine and Maillard reaction products, which are highly reactive and harmful. The enzyme COG3236 hydrolyzes these two first intermediates into two less harmful products, thus preventing the harm they would otherwise cause.
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Elastases form a subfamily of serine proteases that hydrolyze many proteins in addition to elastin. Humans have six elastase genes that encode the structurally similar proteins elastase 1, 2, 2A, 2B, 3A, and 3B. Neutrophil elastase hydrolyzes proteins within specialized neutrophil lysosomes, called azurophil granules, as well as proteins of the extracellular matrix following the protein's release from activated neutrophils. Neutrophil elastase may play a role in degenerative and inflammatory diseases by its proteolysis of collagen-IV and elastin of the extracellular matrix.
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Both LDL and its receptor form vesicles within a cell via endocytosis. These vesicles then fuse with a lysosome, where the lysosomal acid lipase enzyme hydrolyzes the cholesterol esters. The cholesterol can then be used for membrane biosynthesis or esterified and stored within the cell, so as to not interfere with the cell membranes. LDL receptors are used up during cholesterol absorption, and its synthesis is regulated by SREBP, the same protein that controls the synthesis of cholesterol de novo, according to its presence inside the cell.
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Although NPP primarily catalyzes phosphodiester hydrolysis, the enzyme will also catalyze the hydrolysis of phosphate monoesters, though to a much smaller extent. NPP preferentially hydrolyzes phosphate diesters over monoesters by factors of 102-106, depending on the identity of the diester substrate. This ability to catalyze a reaction with a secondary substrate is known as enzyme promiscuity, and may have played a role in NPP's evolutionary history. NPP's promiscuity enables the enzyme to share substrates with alkaline phosphatase (AP), another member of the alkaline phosphate superfamily.
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Holding a sucrose solution at temperatures of hydrolyzes no more than about 85% of its sucrose. Finding \alpha when r = 0.85 shows that the optical rotation of the solution after hydrolysis is done is −12.7° this reaction is said to invert the sugar because its final optical rotation is less than zero. A polarimeter can be used to figure out when the inversion is done by detecting whether the optical rotation of the solution at an earlier time in its hydrolysis reaction equals −12.7°.
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Sporosarcina pasteurii formerly known as Bacillus pasteurii from older taxonomies, is a gram positive bacterium with the ability to precipitate calcite and solidify sand given a calcium source and urea; through the process of microbiologically induced calcite precipitation (MICP) or biological cementation. S. pasteurii has been proposed to be used as an ecologically sound biological construction material. It is a commonly used for MICP since it is non-pathogenic and is able to produce high amounts of the enzyme urease which hydrolyzes urea to carbonate and ammonia.
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The formed 1-arseno-3-phosphoglycerate is unstable and hydrolyzes spontaneously. Thus, ATP formation in glycolysis is inhibited while bypassing the phosphoglycerate kinase reaction. (Moreover, the formation of 2,3-bisphosphoglycerate in erythrocytes might be affected, followed by a higher oxygen affinity of hemoglobin and subsequently enhanced cyanosis.) As shown by Gresser (1981), submitochondrial particles synthesize adenosine-5’-diphosphate-arsenate from ADP and arsenate in presence of succinate. Thus, by a variety of mechanisms arsenate leads to an impairment of cell respiration and subsequently diminished ATP formation.
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In one study a methylene arenium ion is stabilized by metal complexation: :Methylene arenium ion In this reaction sequence the R–Pd(II)–Br starting complex 1 stabilized by TMEDA is converted through dppe to metal complex 2. Electrophilic attack of methyl triflate forms methylene arenium ion 3 with (based on X-ray crystallography) positive charge located in aromatic para position and with the methylene group 6° out of the plane of the ring. Reaction first with water and then with triethylamine hydrolyzes the ether group.
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Maleic anhydride rapidly hydrolyzes to form maleic acid in the presence of water and hence environmental exposures to maleic anhydride itself are unlikely. Maleic acid is biodegradable under aerobic conditions in sewage sludge as well as in soil and water. Food starch for use in night markets sold from a supplier in Tainan city, Taiwan, were found to contain maleic anhydride in December 2013. The supplier was investigated regarding the 300 tons of tainted starch; an earlier inspection in November had found 32 tons.
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Amygdalin was first isolated in 1830 from bitter almond seeds (Prunus dulcis) by Pierre- Jean Robiquet and Antoine Boutron-Charlard. Liebig and Wöhler found three hydrolysis products of amygdalin: sugar, benzaldehyde, and prussic acid (hydrogen cyanide, HCN). Later research showed that sulfuric acid hydrolyzes it into D-glucose, benzaldehyde, and prussic acid; while hydrochloric acid gives mandelic acid, D-glucose, and ammonia. In 1845 amygdalin was used as a cancer treatment in Russia, and in the 1920s in the United States, but it was considered too poisonous.
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This gene is a member of the paraoxonase family and lies in a cluster on chromosome 7 with the other two family members. The encoded protein is secreted into the bloodstream and associates with high- density lipoprotein (HDL). The protein also rapidly hydrolyzes lactones and can inhibit the oxidation of low-density lipoprotein (LDL), a function that is believed to slow the initiation and progression of atherosclerosis. Alternatively spliced variants which encode different protein isoforms have been described; however, only one has been fully characterized.
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The protein encoded by this gene belongs to the cyclic nucleotide phosphodiesterase (PDE) family, and PDE4 subfamily. This PDE hydrolyzes the secondary messenger, cAMP, which is a regulator and mediator of a number of cellular responses to extracellular signals. Thus, by regulating the cellular concentration of cAMP, this protein plays a key role in many important physiological processes. Recently, it has been shown through the use of PDE4A knock out mice that PDE4A may play a role in the regulation of anxiety and emotional memory.
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Bis(5'-nucleosyl)-tetraphosphatase [asymmetrical] is an enzyme that in humans is encoded by the NUDT2 gene. This gene encodes a member of the MutT family of nucleotide pyrophosphatases, a subset of the larger NUDIX hydrolase family. The gene product possesses a modification of the MutT sequence motif found in certain nucleotide pyrophosphatases. The enzyme asymmetrically hydrolyzes Ap4A to yield AMP and ATP and is responsible for maintaining the intracellular level of the dinucleotide Ap4A, the function of which has yet to be established.
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BiP contains two functional domains: a nucleotide-binding domain (NBD) and a substrate-binding domain (SBD). The NBD binds and hydrolyzes ATP, and the SBD binds polypeptides. The NBD consists of two large globular subdomains (I and II), each further divided into two small subdomains (A and B). The subdomains are separated by a cleft where the nucleotide, one Mg2+, and two K+ ions bind and connect all four domains (IA, IB, IIA, IIB). The SBD is divided into two subdomains: SBDβ and SBDα.
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This rod-shaped bacterium has the ability to produce high levels of urease, which hydrolyzes urea to ammonia (NH3), so makes the urine more alkaline. If left untreated, the increased alkalinity can lead to the formation of crystals of struvite, calcium carbonate, and/or apatite, which can result in kidney stones. The bacterium can be found throughout the stones, and these bacteria lurking in the kidney stones can reinitiate infection after antibiotic treatment. Once the stones develop, over time they may grow large enough to cause obstruction and kidney failure.
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In the phosphatidylinositol signal pathway, the extracellular signal molecule binds with the G-protein receptor (Gq) on the cell surface and activates phospholipase C, which is located on the plasma membrane. The lipase hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) into two second messengers: inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). IP3 binds with the IP3 receptor in the membrane of the smooth endoplasmic reticulum and mitochondria to open Ca2+ channels. DAG helps activate protein kinase C (PKC), which phosphorylates many other proteins, changing their catalytic activities, leading to cellular responses.
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Group specificity occurs when an enzyme will only react with molecules that have specific functional groups, such as aromatic structures, phosphate groups, and methyls. One example is Pepsin, an enzyme that is crucial in digestion of foods ingested in our diet, that hydrolyzes peptide bonds in between hydrophobic amino acids, with recognition for aromatic side chains such as phenylalanine, tryptophan, and tyrosine. Another example is hexokinase, an enzyme involved in glycolysis that phosphorylate glucose to produce glucose-6-phosphate. This enzyme exhibits group specificity by allowing multiple hexoses (6 carbon sugars) as its substrate.
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In dilute aqueous solution, such as is commonly used for Enhanced Oil Recovery applications, polyacrylamide polymers are susceptible to chemical, thermal, and mechanical degradation. Chemical degradation occurs when the labile amide moiety hydrolyzes at elevated temperature or pH, resulting in the evolution of ammonia and a remaining carboxyl group. Thus, the degree of anionicity of the molecule increases. Thermal degradation of the vinyl backbone can occur through several possible radical mechanisms, including the autooxidation of small amounts of iron and reactions between oxygen and residual impurities from polymerization at elevated temperature.
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Arsenate can replace inorganic phosphate in the step of glycolysis that produces 1,3-bisphosphoglycerate from glyceraldehyde 3-phosphate. This yields 1-arseno-3-phosphoglycerate instead, which is unstable and quickly hydrolyzes, forming the next intermediate in the pathway, 3-phosphoglycerate. Therefore, glycolysis proceeds, but the ATP molecule that would be generated from 1,3-bisphosphoglycerate is lost – arsenate is an uncoupler of glycolysis, explaining its toxicity. As with other arsenic compounds, arsenite binds to lipoic acid, inhibiting the conversion of pyruvate into acetyl-CoA, blocking the Krebs cycle and therefore resulting in further loss of ATP.
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The alpha subunit interacts with the inhibitory PDE gamma subunits and prevents them from blocking catalytic sites on the alpha and beta subunits of PDE, leading to the activation of cGMP phosphodiesterase, which hydrolyzes cGMP (the second messenger), breaking it down into 5'-GMP. Reduction in cGMP allows the ion channels to close, preventing the influx of positive ions, hyperpolarizing the cell, and stopping the release of the neurotransmitter glutamate (Kandel et al., 2000). Though cone cells primarily use the neurotransmitter substance acetylcholine, rod cells use a variety.
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When the content of the SprüBü37 comes in contact with water, only the mustard gas in the outer layers of the lumps of viscous mustard hydrolyzes, leaving behind amber-colored residues that still contain most of the active mustard gas. On mechanically breaking these lumps, e.g., with the drag board of a fishing net or by the human hand, the enclosed mustard gas is still as active as it had been at the time the weapon was dumped. These lumps, when washed ashore, can be mistaken for amber, which can lead to severe health problems.
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As expected for a sulfide salt of alkaline earth, the sulfide hydrolyzes readily: :SrS + 2 H2O → Sr(OH)2 \+ H2S For this reason, samples of SrS have an odor of rotten eggs. Similar reactions are used in the production of commercially useful compounds, including the most useful strontium compound, strontium carbonate: a mixture of strontium sulfide with either carbon dioxide gas or sodium carbonate leads to formation of a precipitate of strontium carbonate. :SrS + H2O + CO2 → SrCO3 \+ H2S :SrS + Na2CO3 → SrCO3 \+ Na2S Strontium nitrate can also be prepared in this way.
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Acarbose inhibits enzymes (glycoside hydrolases) needed to digest carbohydrates, specifically, alpha- glucosidase enzymes in the brush border of the small intestines, and pancreatic alpha-amylase. Pancreatic alpha-amylase hydrolyzes complex starches to oligosaccharides in the lumen of the small intestine, whereas the membrane- bound intestinal alpha-glucosidases hydrolyze oligosaccharides, trisaccharides, and disaccharides to glucose and other monosaccharides in the small intestine. Inhibition of these enzyme systems reduces the rate of digestion of complex carbohydrates. Less glucose is absorbed because the carbohydrates are not broken down into glucose molecules.
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Nuclear export roughly reverses the import process; in the nucleus, the exportin binds the cargo and Ran-GTP and diffuses through the pore to the cytoplasm, where the complex dissociates. Ran-GTP binds GAP and hydrolyzes GTP, and the resulting Ran-GDP complex is restored to the nucleus where it exchanges its bound ligand for GTP. Hence, whereas importins depend on RanGTP to dissociate from their cargo, exportins require RanGTP in order to bind to their cargo. A specialized mRNA exporter protein moves mature mRNA to the cytoplasm after post-transcriptional modification is complete.
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Plants store starch within specialized organelles called amyloplasts. When energy is needed for cell work, the plant hydrolyzes the starch, releasing the glucose subunits. Humans and other animals that eat plant foods also use amylase, an enzyme that assists in breaking down amylopectin. Starch is made of about 80–85% amylopectin by weight, though it varies depending on the source (higher in medium-grain rice to 100% in glutinous rice, waxy potato starch, and waxy corn, and lower in long-grain rice, amylomaize, and russet potatoes, for example).
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Antisense oligonucleotides are single strands of DNA or RNA that are complementary to a chosen sequence. In the case of antisense RNA they prevent protein translation of certain messenger RNA strands by binding to them, in a process called hybridization. Antisense oligonucleotides can be used to target a specific, complementary (coding or non-coding) RNA. If binding takes place this hybrid can be degraded by the enzyme RNase H. RNase H is an enzyme that hydrolyzes RNA, and when used in an antisense oligonucleotide application results in 80-95% down-regulation of mRNA expression.
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Three genes have been characterized in the 31-kb region which contains all genes necessary for TβL synthesis and tabtoxin resistance: tabA, tabB, and tblA. Although there is no obvious relationship between TblA and known polypeptides, TabA has significant sequence homology to LysA from E. coliand P. aeruginosa whereas TabB shows relatedness to DapD. Some progress has been made on elucidating factors that regulate tabtoxin biosynthesis in P. syringae. In a subsequent study, zinc was shown to be required for the aminopeptidase activity, which hydrolyzes tabtoxin to release TβL.
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The MT-ATP8 gene encodes a subunit of mitochondrial ATP synthase, located within the thylakoid membrane and the inner mitochondrial membrane. Mitochondrial ATP synthase catalyzes ATP synthesis, utilizing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation. The Fo region causes rotation of F1, which has a water-soluble component that hydrolyzes ATP and together, the F1Fo creates a pathway for movement of protons across the membrane. This protein subunit appears to be an integral component of the stator stalk in yeast mitochondrial F-ATPases.
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The β-tubulin subunit is exposed on the plus end of the microtubule while the α-tubulin subunit is exposed on the minus end. After the dimer is incorporated into the microtubule, the molecule of GTP bound to the β-tubulin subunit eventually hydrolyzes into GDP through inter-dimer contacts along the microtubule protofilament. The GTP molecule bound to the α-tubulin subunit is not hydrolyzed during the whole process. Whether the β-tubulin member of the tubulin dimer is bound to GTP or GDP influences the stability of the dimer in the microtubule.
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Glucose-6-phosphate Glucose Glucose 6-phosphatase (, G6Pase) is an enzyme that hydrolyzes glucose 6-phosphate, resulting in the creation of a phosphate group and free glucose. Glucose is then exported from the cell via glucose transporter membrane proteins. This catalysis completes the final step in gluconeogenesis and therefore plays a key role in the homeostatic regulation of blood glucose levels. Glucose 6-phosphatase is a complex of multiple component proteins, including transporters for G6P, glucose, and phosphate. The main phosphatase function is performed by the glucose 6-phosphatase catalytic subunit.
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At the plasma membrane, the protein hydrolyzes the 5' phosphate from phosphatidylinositol (3,4,5)-trisphosphate and inositol-1,3,4,5-tetrakisphosphate, thereby influence the binding of many proteins to the cytoplasmic membrane thus affecting multiple signaling pathways. To access the substrate which is located on the cytoplasmic membrane, SHIP1 move from cytosol to the plasma membrane. This movement is mediated by binding its SH2 domain to the phosphorylated intracellular chains of cell surface receptors. Binding SHIP1 to phosphorylated immunoreceptor tyrosine-based inhibition motifs (ITIM) of FcγRIIB inhibits the activation of B cells including Ca2+ influx.
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The AAA domain contains two subdomains, an N-terminal alpha/beta domain that binds and hydrolyzes nucleotides (a Rossmann fold) and a C-terminal alpha-helical domain. The N-terminal domain is 200-250 amino acids long and contains Walker A and Walker B motifs, and is shared in common with other P-loop NTPases, the superfamily which includes the AAA family. Most AAA proteins have additional domains that are used for oligomerization, substrate binding and/or regulation. These domains can lie N- or C-terminal to the AAA module.
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Previously known as the photoreceptor rim protein RmP or ABCR, the recently proposed ABCA4 structure consists of two transmembrane domains (TMDs), two large glycosylated extracytosolic domains (ECD), and two internal nucleotide binding domains (NBDs). One TMD spans across membranes with six units of protein linked together to form a domain. The TMDs are usually not conserved across genomes due to its specificity and diversity in function as channels or ligand-binding controllers. However, NBDs are highly conserved across different genomes—an observation consistent with which it binds and hydrolyzes ATP.
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Acetone imine is prepared by dehydrocyanation of the cyanoamine of acetone, which is prepared from acetone cyanohydrin. Dicyclohexylcarbodiimide (CyN=C=NCy) serves as the scavenger for hydrogen cyanide: :(CH3)2C(NH2)CN + CyN=C=NCy → (CH3)2CNH + CyN(H)-C(CN)=NCy :Upon standing at room temperature, samples of acetone imine degrade to give this heterocycle, called acetonin. The compound hydrolyzes readily: :(CH3)2CNH + H2O → (CH3)2CO + NH3 This reactivity is characteristic of imines derived from ammonia. Methylene imine (CH2=NH) is also highly reactive, condensing to hexamethylenetetramine.
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Stink bombs At the lower end of the spectrum, relatively harmless stink bombs consist of ammonium sulfide, which smells strongly of rotten eggs. When exposed to air, the ammonium sulfide reacts with moisture, hydrolyzes, and a mixture of hydrogen sulfide (rotten egg smell) and ammonia is released. Other popular substances on which to base stink bombs are thiols with lower molecular weight, e.g., methyl mercaptan and ethyl mercaptan—the chemicals that give odor to skunks and are added in minute quantities to natural gas in order to make gas leaks detectable by smell.
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Lystek's technology uses thermal hydrolysis involving high speed shearing, alkali addition and low temperature steam to produce biofertilizer. The product can be sold as a commercial biofertilizer called LysteGro or recycled to anaerobic digesters and biological nutrient removal (BNR) systems for optimization of the wastewater treatment plant operation. The Lystek process condition disintegrates microbial cell wall/membranes and hydrolyzes complex macromolecules into simpler compounds. Recycling up to 25% of the product to the digester increases biogas yields by greater than 30 % and enhances biodegradation, reducing output of biosolids by at least 20%.
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OBPgp279 (OBP genome protein 279) is an endolysin that hydrolyzes peptidoglycan, a major constituent in bacterial membrane. OBPgp279 is found in Pseudomonas fluorescens phage OBP, which belongs in the Myoviridae family of bacteriophages. Because of its role in hydrolyzing the peptidoglycan layer, OBPgp279 is a key enzyme in the lytic cycle of the OBP bacteriophage; it allows the bacteriophage to lyse its host internally to escape. Unlike other endolysins, OBPgp279 does not rely on holins to perforate the inner bacterial membrane in order to reach the peptidoglycan layer.
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Calaspargase pegol, sold under the brand name Asparlas, is a medication for the treatment of acute lymphoblastic leukemia (ALL). It is approved in the United States as a component of a multi-agent chemotherapeutic regimen for ALL in pediatric and young adult patients aged one month to 21 years. Calaspargase pegol is an engineered protein consisting of the E. coli-derived enzyme L-asparaginase II conjugated with succinimidyl carbonate monomethoxypolyethylene glycol (pegol). The L-asparaginase portion hydrolyzes L-asparagine to L-aspartic acid depriving the tumor cell of the L-asparagine it needs for survival.
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Sulfur and selenium tetrafluorides are molecular while TeF4 is a polymer. The hexafluorides are the result of direct fluorination of the elements (compare: other hexahalides of these elements do not even exist). They increase in reactivity with atomic number: SF6 is extremely inert, SeF6 is less noble (for example, reacts with ammonia at 200 °C (400 °F)), and TeF6 easily hydrolyzes to give an oxoacid. Oxygen's highest fluoride is oxygen difluoride, but fluorine can theoretically (as of 2012) oxidize it to a uniquely high oxidation state of +4 in the fluorocation: .
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Vesicular transporters rely on a proton gradient created by the hydrolysis of adenosine triphosphate (ATP) in order to carry out their work: v-ATPase hydrolyzes ATP, causing protons to be pumped into the synaptic vesicles and creating a proton gradient. Then the efflux of protons from the vesicle provides the energy to bring the neurotransmitter into the vesicle. Neurotransmitter transporters frequently use electrochemical gradients that exist across cell membranes to carry out their work. For example, some transporters use energy obtained by the cotransport, or symport, of Na+ in order to move glutamate across membranes.
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Dispersin B is a β-hexosaminidase that specifically hydrolyzes β-1,6-glycosidic linkages of acetylglucosamine polymers found in biofilm matrices. As a member of family 20 β-hexosaminidases, it cleaves terminal monosaccharide residues from the non- reducing end of the polymers. The active site of Dispersin B contains three highly conserved acidic residues: an aspartic acid at residue 183 (D183), a glutamic acid at residue 184 (E184), and a glutamic acid at residue 332 (E332). In the proposed mechanism, E184 serves as the acid/base and donates a proton to the -OR on C1.
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The first proposes that the GTP-bound-Tα releases the PDE γ subunit from the catalytic subunits in order to activate hydrolysis. The second more likely mechanism proposes that binding causes a positional shift of the γ subunit, allowing better accessibility of the catalytic subunit for cGMP hydrolysis. The GTPase activity of Tα hydrolyzes GTP to GDP and changes the conformation of the Tα subunit, increasing its affinity to bind to the α and β subunits on the PDE. The binding of Tα to these larger subunits results in another conformational change in PDE and inhibits the hydrolysis ability of the catalytic subunit.
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FFA1 is found in highest concentration in Islets of Langerhans, the endocrine portion of the pancreas. Activation of FFA1 results in an increase in cytosolic Ca2+ via the phosphoinositide pathway. When a free fatty acid docks on FFA1, the membrane protein becomes activated. This activation causes one of its subunits to dissociate from the receptor, which then activates phospholipase C (PLC) which is found in the cell membrane. PLC in turn hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2),which is also in the membrane, to diacyl glycerol (DAG) which stays in the membrane, and inositol 1,4,5-triphosphate (IP3), which enters the cytosol.
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Aryldialkylphosphatase (EC 3.1.8.1) (more commonly known as phosphotriesterase (PTE), and also organophosphate hydrolase, parathion hydrolase, paraoxonase, and parathion aryl esterase) is a metalloenzyme that hydrolyzes the triester linkage found in organophosphate insecticides. :an aryl dialkyl phosphate + H2O \rightleftharpoons dialkyl phosphate + an aryl alcohol Thus, the two substrates of this enzyme are aryldialkylphosphate and H2O, whereas its two products are dialkylphosphate and aryl alcohol. The gene (opd, for organophosphate-degrading) that codes for the enzyme is found in a large plasmid (pSC1, 51Kb) endogenous to Pseudomonas diminuta, although the gene has also been found in many other bacterial species such as Flavobacterium sp.
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Succinyl-CoA ligase [ADP-forming] subunit beta, mitochondrial (SUCLA2), also known as ADP-forming succinyl-CoA synthetase (SCS-A), is an enzyme that in humans is encoded by the SUCLA2 gene on chromosome 13. Succinyl-CoA synthetase (SCS) is a mitochondrial matrix enzyme that acts as a heterodimer, being composed of an invariant alpha subunit and a substrate-specific beta subunit. The protein encoded by this gene is an ATP-specific SCS beta subunit that dimerizes with the SCS alpha subunit to form SCS-A, an essential component of the tricarboxylic acid cycle. SCS-A hydrolyzes ATP to convert succinyl-CoA to succinate.
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At pH 7, glucose exists in solution in cyclic hemiacetal form as 63.6% β-D-glucopyranose and 36.4% α-D-glucopyranose, the proportion of linear and furanose form being negligible. The glucose oxidase binds specifically to β-D-glucopyranose and does not act on α-D-glucose. It is able to oxidise all of the glucose in solution because the equilibrium between the α and β anomers is driven towards the β side as it is consumed in the reaction. Glucose oxidase catalyzes the oxidation of β-D-glucose into D-glucono-1,5-lactone, which then hydrolyzes to gluconic acid.
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Lipid phosphate phosphohydrolase 3 (LPP3), also known as phospholipid phosphatase 3 (PLPP3) and phosphatidic acid phosphatase type 2B (PAP-2b or PPAP2B), is an enzyme that in humans is encoded by the PPAP2B gene on chromosome 1. It is ubiquitously expressed in many tissues and cell types. LPP3 is a cell-surface glycoprotein that hydrolyzes extracellular lysophosphatidic acid (LPA) and short-chain phosphatidic acid. Its function allows it to regulate vascular and embryonic development by inhibiting LPA signaling, which is associated with a wide range of human diseases, including cardiovascular disease and cancer, as well as developmental defects.
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Then is easily oxidized to and this latter rapidly hydrolyzes and precipitates because of its lower solubility due to a higher z/r ratio. Millot (1970) also illustrated the importance of the ionic potential of cations to explain the high, or the low, solubility of minerals and the expansive behaviour (swelling/shrinking) of clay materials. The ionic potential of the different cations (, , and ) present in the interlayer of clay minerals also contribute to explain their swelling/shrinking properties. The more hydrated cations such as and are responsible for the swelling of smectite while the less hydrated and cause the collapse of the interlayer.
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Despite the power of this approach to catalyze the enantioselective functionalization of carbonyl compounds, certain valuable transformations, such as the catalytic enantioselective α-alkylation of aldehydes, remained elusive. The combination of organocatalysis and photoredox methods provides a catalytic solution to this problem. In this approach for the α-alkylation of aldehydes, [Ru(bipy)3]2+ reductively fragments an activated alkyl halide, such as bromomalonate or phenacyl bromide, which can then add to catalytically-generated enamine in an enantioselective manner. The oxidized photocatalyst then oxidatively quenches the resulting α-amino radical to form an iminium ion, which hydrolyzes to give the functionalized carbonyl compound.
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Watch glass with two grams of chromium(III) picolinate Skeletal stick model (hydrogen atoms omitted) of the chromium(III) picolinate complex Chromium(III) picolinate is a pinkish-red compound and was first reported in 1917. It is poorly soluble in water, having a solubility of 600 μM in water at near neutral pH. Similar to other chromium(III) compounds, it is relatively inert and unreactive, meaning that this complex is stable at ambient conditions and high temperatures are required to decompose the compound. At lower pH levels, the complex hydrolyzes to release picolinic acid and free Cr3+.
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Trimethylsilyl cyanide hydrolyzes to give hydrogen cyanide and trimethylsilanol: :(CH3)3SiCN + H2O -> (CH3)3SiOH + HCN In its principal application, it adds across carbon-oxygen double bonds, for example in an aldehyde, to form a new carbon-carbon bond: : + (CH3)3SiC≡N -> N≡C-Si(CH3)3 The product is an O-silylated cyanohydrin. One use of this reagent is to convert pyridine-N-oxides into 2-cyanopyridine. This transformation is best done in dichloromethane solution using dimethylcarbamoyl chloride as the activating electrophile. It is possible to use benzoyl chloride but the yields and regioselectivity of the addition of the cyano group are lower.
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It can be produced by heating K2SO4 with carbon (coke): :K2SO4 \+ 4 C → K2S + 4 CO In the laboratory, pure K2S may be prepared by the reaction of potassium and sulfur in anhydrous ammonia. Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 360. Sulfide is highly basic, consequently K2S completely and irreversibly hydrolyzes in water according to the following equation: :K2S + H2O → KOH + KSH For many purposes, this reaction is inconsequential since the mixture of SH− and OH− behaves as a source of S2−. Other alkali metal sulfides behave similarly.
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The polymerization reaction is an example of a step-growth polymerization to a polyamide and in one practical procedure aspartic acid is simply heated to 180 °C resulting in water release and the formation of a poly(succinimide). In the subsequent step, this polymer is reacted with sodium hydroxide in water, which hydrolyzes one of the two amide bonds of the succinimide ring to form a sodium carboxylate. The remaining amide bond is thus the linkage between successive aspartate units. Each aspartate unit is identified as α or β according to which carbonyl of it is part of the polymer chain.
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A protein translated with a NLS will bind strongly to importin (aka karyopherin), and, together, the complex will move through the nuclear pore. At this point, Ran-GTP will bind to the importin-protein complex, and its binding will cause the importin to lose affinity for the protein. The protein is released, and now the Ran-GTP/importin complex will move back out of the nucleus through the nuclear pore. A GTPase-activating protein (GAP) in the cytoplasm hydrolyzes the Ran-GTP to GDP, and this causes a conformational change in Ran, ultimately reducing its affinity for importin.
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Laevorotatory describes the stereochemistry of the molecule, while mandelonitrile refers to the portion of the molecule from which cyanide is released by decomposition. A 500 mg laetrile tablet may contain between 2.5–25 mg of hydrogen cyanide. Like amygdalin, laetrile is hydrolyzed in the duodenum (alkaline) and in the intestine (enzymatically) to D-glucuronic acid and L-mandelonitrile; the latter hydrolyzes to benzaldehyde and hydrogen cyanide, that in sufficient quantities causes cyanide poisoning. Claims for laetrile were based on three different hypotheses: The first hypothesis proposed that cancerous cells contained copious beta-glucosidases, which release HCN from laetrile via hydrolysis.
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Ixazomib citrate (MLN9708), the prodrug for ixazomib The medication is taken orally as a prodrug, ixazomib citrate, which is a boronic ester; this ester rapidly hydrolyzes under physiological conditions to its biologically active form, ixazomib, a boronic acid. Absolute bioavailability is 58%, and highest blood plasma concentrations of ixazomib are reached after one hour. Plasma protein binding is 99%. The substance is metabolized by many CYP enzymes (percentages in vitro, at higher than clinical concentrations: CYP3A4 42.3%, CYP1A2 26.1%, CYP2B6 16.0%, CYP2C8 6.0%, CYP2D6 4.8%, CYP2C9 4.8%, CYP2C9 <1%) as well as non-CYP enzymes, which could explain the low interaction potential.
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The alternative pathway of complement activation is typically always active at low levels in blood plasma through a process called tick-over, in which C3 spontaneously hydrolyzes into its active form, C3(H2O). This activation induces a conformational change in the thioester domain of C3(H2O) that allows it to bind to a plasma protein called Factor B. This complex is then cleaved by Factor D, a serine protease, to form C3b(H2O)Bb, or fluid-phase C3-convertase. This complex has the ability to catalyze the formation of C3a and C3b after it binds properdin, a globulin protein, and is stabilized.
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The test is performed at the time of gastroscopy. A biopsy of mucosa is taken from the antrum of the stomach, and is placed into a medium containing urea and an indicator such as phenol red. The urease produced by H. pylori hydrolyzes urea to ammonia, which raises the pH of the medium, and changes the color of the specimen from yellow (NEGATIVE) to red (POSITIVE). Among different kinds of rapid urease tests (liquid-based, gel-based, dry cool) there is a design type with single-layer sensitive element — a layer impregnated simultaneously with urea and an indicator composition.
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There are many studies taking place to further understand how the lysosomal acid lipase disease works at a cellular and molecular level, which can be applied to the development of new treatments for these diseases. One study called "Role of lysosomal acid lipase in the metabolism of plasma low density lipoprotein. Observations in cultured fibroblasts from a patient with cholesteryl ester storage disease." looks at the ability of human fibroblasts to hydrolyzes the cholesteryl esters of exogenous LDL and thus provides the cell with free cholesterol. Other studies look at the fact that acid lipase disease is often under diagnosed.
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Unlike permanganate (), it is only a weak oxidizing agent. Related to pertechnetate is heptoxide. This pale-yellow, volatile solid is produced by oxidation of Tc metal and related precursors: :4 Tc + 7 O2 → 2 Tc2O7 It is a very rare example of a molecular metal oxide, other examples being OsO4 and RuO4. It adopts a centrosymmetric structure with two types of Tc−O bonds with 167 and 184 pm bond lengths. Technetium heptoxide hydrolyzes to pertechnetate and pertechnetic acid, depending on the pH: : :Tc2O7 \+ 2 OH− → 2 TcO4− \+ H2O :Tc2O7 \+ H2O → 2 HTcO4 HTcO4 is a strong acid.
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Benzotrichloride hydrolyzes rapidly in the presence of water into benzoic acid and hydrochloric acid with a half life of about 2.4 minutes, thus making the compound unstable in the presence of water. In other chemical reactions, BTC reacts at the chlorinated α-carbon, for example in substitution reactions. BTC is a poorly water-soluble, clear to yellowish liquid with a penetrating odor. The synthesis of BTC is performed by free radical chlorination of toluene. BTC is used as an intermediate in the synthesis of benzoyl chloride, benzotrifluoride and 2,4-dihydroxybenzophenone which in turn are also intermediates in other reactions.
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However, because OBPgp279 is analogous to family 19, it is possible to infer the structure of OBPgp279 binding to peptidoglycan from the substrate binding of glycoside hydrolase family 19. The figure on the right shows an example of a glycoside hydrolase family 19 binding to chitin. OBPgp279 most likely has a similar active site, but it binds to peptidoglycan instead of chitin. Due to the activity of OBPgp279 on β-1,4-linked GlcNAc, it is likely that OBPgp279 is a N-acetylmuramidase (lysozyme-like) endolysin which hydrolyzes the sugar backbone component of the peptidoglycan on the reducing side of GlcNAc.
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Its purpose in most tablets – including dietary supplements – is to assist the tablet in disintegrating in the gastrointestinal tract promptly. If a tablet disintegrating agent is not included, the tablet could disintegrate too slowly, in the wrong part of the intestine or not at all, thereby reducing the efficacy and bioavailability of the active ingredients. Croscarmellose is made by first soaking crude cellulose in sodium hydroxide, and then reacting the cellulose with sodium monochloroacetate to form sodium carboxymethylcellulose. Excess sodium monochloroacetate slowly hydrolyzes to glycolic acid and the glycolic acid catalyzes the cross-linkage to form sodium croscarmellose.
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Nitrogen dioxide is sparingly soluble in water and on inhalation, it diffuses into the lung and slowly hydrolyzes to nitrous and nitric acid which causes pulmonary edema and pneumonitis leading to the inflammation of the bronchioles and pulmonary alveolus resulting from lipid peroxidation and oxidative stress. Mucous membrane is primarily affected alongside with type I pneumocyte and the respiratory epithelium. The generation of free radicals from lipid peroxidation results in irritation of the bronchioles and alveoli that causes rapid destruction of the respiratory epithelial cells. The overall reaction results in the release of fluid that causes pulmonary edema.
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One challenge for the 'exonuclease approach', where a processive enzyme feeds individual bases, in the correct order, into the nanopore, is to integrate the exonuclease and the nanopore detection systems. In particular, the problem is that when an exonuclease hydrolyzes the phosphodiester bonds between nucleotides in DNA, the subsequently released nucleotide is not necessarily guaranteed to directly move into, say, a nearby alpha-hemolysin nanopore. One idea is to attach the exonuclease to the nanopore, perhaps through biotinylation to the beta barrel hemolysin. The central pore of the protein may be lined with charged residues arranged so that the positive and negative charges appear on opposite sides of the pore.
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The hydrogen is used to reduce two molecules of NAD+, a hydrogen carrier, to give NADH + H+ for each triose. Hydrogen atom balance and charge balance are both maintained because the phosphate (Pi) group actually exists in the form of a hydrogen phosphate anion (HPO42−), which dissociates to contribute the extra H+ ion and gives a net charge of -3 on both sides. Here, arsenate (AsO43−), an anion akin to inorganic phosphate may replace phosphate as a substrate to form 1-arseno-3-phosphoglycerate. This, however, is unstable and readily hydrolyzes to form 3-phosphoglycerate, the intermediate in the next step of the pathway.
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In this pathway, G-coupled protein receptors and tyrosine kinase receptors are activated, resulting in the activation of phospholipase C (PLC). PLC hydrolyzes phosphatidylinositol biphosphate (PIP2), resulting in a membrane associated product, diacylglycerol (DAG), and a water-soluble product, inositol triphosphate (IP3). DAG acts as a second messenger, activating several protein kinases and produces extended downstream signaling. IP3 is also a second messenger which activates receptors on the endoplasmic reticulum to release calcium ion stores into the cytoplasm, creating a complex signaling system that can be involved in modulating fertilization, proliferation, contraction, cell metabolism, vesicle and fluid secretion, and information processing in neuronal cells.
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Renin (etymology and pronunciation), also known as an angiotensinogenase, is an aspartic protease protein and enzyme secreted by the kidneys that participates in the body's renin–angiotensin–aldosterone system (RAAS)—also known as the renin–angiotensin–aldosterone axis—that mediates the volume of extracellular fluid (blood plasma, lymph and interstitial fluid) and arterial vasoconstriction. Thus, it regulates the body's mean arterial blood pressure. Renin can also be referred to as a hormone, as it has a receptor, the (pro)renin receptor, also known as the renin receptor and prorenin receptor (see also below), as well as enzymatic activity with which it hydrolyzes angiotensinogen to angiotensin I.
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Neurolysin hydrolyzes only peptides containing 5-17 amino acids by cleaving at a limited set of sites. The specificity of neurolysin for small bioactive peptides is due to the presence of large structural elements erected over its active site region that allow substrates access only through a deep narrow channel. In vitro, neurolysin exemplifies the ability of some neuropeptidases to target diverse cleavage site sequences. In vivo, their most established role is cleaving neurotensin between its 10th and 11th residues to produce inactive fragments and it has been recently identified as a non-AT1-non-AT2 angiotensin-binding site, with function pertaining to the rennin-angiotensin system.
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In red/blue Phe105-Met106 bond of κ- casein Chymosin (EC 3.4.23.4) is an aspartic protease that specifically hydrolyzes the peptide bond in Phe105-Met106 of κ- casein and is considered to be the most efficient protease for the cheesemaking industry. However, there are milk-clotting proteases able to cleave other peptide bonds in the κ-casein chain, such as the endothiapepsin produced by Endothia parasitica. There are also several milk-clotting proteases that, being able to cleave the Phe105-Met106 bond in the κ-casein molecule, also cleave other peptide bonds in other caseins, such as those produced by Cynara cardunculus or even bovine chymosin.
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Glutamyl endopeptidase is in at least some species part of a zymogen activation cascade, with its activity being dependent on proteolytic activation of a pre- form of the protease. GluV8 of S. aureus, for example, is dependent of activation by the metalloprotease aureolysin, and is itself needed for activation of staphopain B. GluSE, GluSW and SprE have been observed to be activated by a metalloprotease in a similar fashion. Proteases of this group hydrolyzes peptide bonds after the negatively charged glutamic acid or aspartic acid, with a higher preference to the former. The pH optimum has been found to lie slightly above neutral pH (7-8) for GluV8 and GluBL.
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Most of the known phytases belong to a class of enzyme called histidine acid phosphatases (HAPs). HAPs have been isolated from filamentous fungi, bacteria, yeast, and plants. All members of this class of phytase share a common active site sequence motif (Arg-His-Gly-X-Arg-X-Pro) and have a two-step mechanism that hydrolyzes phytic acid (as well as some other phosphoesters). The phytase from the fungus Aspergillus niger is a HAP and is well known for its high specific activity and its commercially marketed role as an animal feed additive to increase the bioavailability of phosphate from phytic acid in the grain-based diets of poultry and swine.
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In eukaryotes and archaea, the amino acid encoded by the start codon is methionine. The Met-charged initiator tRNA (Met-tRNAiMet) is brought to the P-site of the small ribosomal subunit by eukaryotic initiation factor 2 (eIF2). It hydrolyzes GTP, and signals for the dissociation of several factors from the small ribosomal subunit, eventually leading to the association of the large subunit (or the 60S subunit). The complete ribosome (80S) then commences translation elongation. Regulation of protein synthesis is partly influenced by phosphorylation of eIF2 (via the α subunit), which is a part of the eIF2-GTP-Met-tRNAiMet ternary complex (eIF2-TC).
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Phosphoramide is a chemical compound with the molecular formula O=P(NH2)3. It is a derivative of phosphoric acid in which each of the hydroxyl groups have been replaced with an amino group. Phosphoramide arises from the reaction of phosphoryl chloride with ammonia. It is a white solid that is soluble in polar solvents. In moist air, it hydrolyzes to an ammonium salt: :2 H2O + OP(NH2)3 → NH4+[HPO3(NH2)] + NH3 It reacts with sodium hydroxide with loss of ammonia: :NaOH + OP(NH2)3 → NaO2P(NH2)2 \+ NH3 The related thiophosphoryl compound P(=S)(NH2)3 was made from the reaction of thiophosphoryl chloride with ammonia.
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On the species level, indole is considered reliable, as it is positive for P. vulgaris, but negative for P. mirabilis. Most strains produce a powerful urease enzyme, which rapidly hydrolyzes urea to ammonia and carbon monoxide; exceptions are some Providencia strains. Species can be motile, and have characteristic "swarming" patterns. Underlying these behaviors are the somatic O and flagellar H antigens, so named based on Kauffman–White classification. This system is based on historic observations of Edmund Weil (1879–1922) and Arthur Felix (1887–1956) of a thin surface film produced by agar-grown flagellated Proteus strains, a film that resembled the mist produced by breath on a glass.
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In the parathyroid gland, high concentrations of extracellular calcium result in activation of the Gq G-protein coupled cascade through the action of phospholipase C. This hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) to liberate intracellular messengers IP3 and diacylglycerol (DAG). Ultimately, these two messengers result in a release of calcium from intracellular stores into the cytoplasmic space. Hence a high extracellular calcium concentration leads to an increase in the cytoplasmic calcium concentration. In contrast to the mechanism that most secretory cells use, this high cytoplasmic calcium concentration inhibits the fusion of vesicles containing granules of preformed PTH with the membrane of the parathyroid cell, and thus inhibits release of PTH.
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Unlike the importance of phosphate in glycolysis, the presence of arsenate restricts the generation of ATP by forming an unstable anhydride product, through the reaction with D-glyceraldehyde-3-phosphate. The anhydride 1-arsenato-3-phospho-D-glycerate generated readily hydrolyzes due to the longer bond length of As-O compared to P-O. At the mitochondrial level, arsenate uncouples the synthesis of ATP by binding to ADP in the presence of succinate, thus forming an unstable compound that ultimately results in a decrease of ATP net gain. Arsenite (III) metabolites, on the other hand, have limited effect on ATP production in red blood cells.
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The material is formed by heating silicon and sulfur or by the exchange reaction between SiO2 and Al2S3. The material consists of chains of edge-shared tetrahedra, Si(μ-S)2Si(μS)2, etc. A printing error in this book states that rSiSi is 214 picometers, when in fact that distance describes rSiS. Like other silicon sulfur-compounds (e.g., bis(trimethylsilyl)sulfide) SiS2 hydrolyzes readily to release H2S. In liquid ammonia it is reported to form the imide Si(NH)2 and NH4SH, but a recent report has identified crystalline (NH4)2[SiS3(NH3)]·2NH3 as a product which contains the tetrahedral thiosilicate anion, SiS3(NH3).
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P3N5 is thermally less stable than either BN or Si3N4, with decomposition to the elements occurring at temperatures above 850 °C: :2 P3N5 → 6 PN + 2 N2 :4 PN → P4 \+ 2 N2 It is resistant to weak acids and bases, and insoluble in water at room temperature, however it hydrolyzes upon heating to form the ammonium phosphate salts (NH4)2HPO4 and NH4H2PO4. Triphosphorus pentanitride reacts with lithium nitride and calcium nitride to form the corresponding salts of PN47− and PN34−. Heterogenous ammonolyses of triphosphorus pentanitride gives imides such as HPN2 and HP4N7. It has been suggested that these compounds may have applications as solid electrolytes and pigments.
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Encoded by the fusA gene on the str operon, EF-G is made up of 704 amino acids that form 5 domains, labeled Domain I through Domain V. Domain I may be referred to as the G-domain or as Domain I(G), since it binds to and hydrolyzes guanosine triphosphate (GTP). Domain I also helps EF-G bind to the ribosome, and contains the N-terminal of the polypeptide chain. Domain IV is important for translocation, as it undergoes a significant conformational change and enters the A site on the 30S ribosomal subunit, pushing the mRNA and tRNA molecules from the A site to the P site. The five domains may be also separated into two super-domains.
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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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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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Lithium diisopropylamide (LDA) then removes a proton from the 8 position; treatment of that anion with trimethylsilyl iodide leads to the silylated intermediate (4). A second round of LDA then generates a carbanion at the only open position; reaction with methyl iodide leads to the corresponding 5 methyl derivative (5). Treatment of that product with cesium fluoride breaks the carbon–silicon bond, removing the silyl group; aqueous acid then hydrolyzes the oxazoline to afford the free acid (6). This last intermediate is then taken on to the quinolone (9) by essentially the same scheme as that used to prepare difloxacin, with the difference that the chain elongation is by means of Grignard reagent of ethyl bromoacetate.
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This enzyme catalyses the following chemical reaction : 2-hydroxy-dATP + H2O \rightleftharpoons 2-hydroxy-dAMP + diphosphate The enzyme hydrolyses oxidized purine nucleoside triphosphates. The enzyme is used in DNA repair, where it hydrolysis the oxidized purines and prevents their addition onto the DNA chain. Misincorporation of oxidized nucleoside triphosphates into DNA and/or RNA during replication and transcription can cause mutations that may result in carcinogenesis or neurodegeneration. First isolated from Escherichia coli because of its ability to prevent occurrence of 8-oxoguanine in DNA, the protein encoded by this gene is an enzyme that hydrolyzes oxidized purine nucleoside triphosphates, such as 8-oxo-dGTP, 8-oxo-dATP, 2-oxo-dATP, 2-hydroxy-dATP, and 2-hydroxy rATP, to monophosphates, thereby preventing misincorporation.
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The compound is prepared by the reaction of boron trifluoride with dimethyl ether and epichlorohydrin: : 4 \+ 2 \+ 3 → 3 \+ The salt hydrolyzes readily: : + → + + Trimethyloxonium tetrafluoroborate is generally ranked as the strongest commercially available reagent for electrophilic methylation, being stronger than methyl sulfonate esters, including methyl triflate and methyl fluorosulfonate ("magic methyl"). Only the exotic dimethylhalonium reagents (, X = Cl, Br, I), methyl carboranate reagents, and the transiently-generated methyldiazonium cation () are stronger sources of electrophilic methyl. Due to its high reactivity, it is rapidly destroyed by atmospheric moisture and best stored in an inert atmosphere glovebox at −20 °C. Its degradation products are corrosive, although it is considerably less hazardous than methyl triflate or methyl fluorosulfonate, on account of its lack of volatility.
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Microbiological sources of exoenzymes including amylases, proteases, pectinases, lipases, xylanases, cellulases among others are used for a wide range of biotechnological and industrial uses including biofuel generation, food production, paper manufacturing, detergents and textile production. Optimizing the production of biofuels has been a focus of researchers in recent years and is centered around the use of microorganisms to convert biomass into ethanol. The enzymes that are of particular interest in ethanol production are cellobiohydrolase which solubilizes crystalline cellulose and xylanase that hydrolyzes xylan into xylose. One model of biofuel production is the use of a mixed population of bacterial strains or a consortium that work to facilitate the breakdown of cellulose materials into ethanol by secreting exoenzymes such as cellulases and laccases.
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The pyrophosphate anion has the structure , and is an acid anhydride of phosphate. It is unstable in aqueous solution and hydrolyzes into inorganic phosphate: : + H2O → 2 or in biologists' shorthand notation: :PPi \+ H2O → 2 Pi \+ 2 H+ In the absence of enzymic catalysis, hydrolysis reactions of simple polyphosphates such as pyrophosphate, linear triphosphate, ADP, and ATP normally proceed extremely slowly in all but highly acidic media. (The reverse of this reaction is a method of preparing pyrophosphates by heating phosphates.) This hydrolysis to inorganic phosphate effectively renders the cleavage of ATP to AMP and PPi irreversible, and biochemical reactions coupled to this hydrolysis are irreversible as well. PPi occurs in synovial fluid, blood plasma, and urine at levels sufficient to block calcification and may be a natural inhibitor of hydroxyapatite formation in extracellular fluid (ECF).
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Proprotein convertase 1 is the enzyme largely responsible for the first step in the biosynthesis of insulin. Following the action of proprotein convertase 1, a carboxypeptidase is required to remove the basic residues from the processing intermediate and generate the bioactive form of insulin. Another prohormone convertase, proprotein convertase 2 plays a more minor role in the first step of insulin biosynthesis, but a greater role in the first step of glucagon biosynthesis. The knockout of proprotein convertase 1 is not lethal in mice or humans, most likely due to the presence of the second convertase, although mice lacking proprotein convertase 1 activity show a number of defects including slow growth. Proprotein convertase 1 is a calcium (Ca2+) activated serine endoprotease (meaning that a serine residue is part of the active site that hydrolyzes the peptide bond within the substrate).
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The microbial urease catalyzes the hydrolysis of urea into ammonium and carbonate. One mole of urea is hydrolyzed intracellularly to 1 mol of ammonia and 1 mole of Carbamic acid (1), which spontaneously hydrolyzes to form an additional 1 mole of ammonia and carbonic acid (2). CO(NH2)2 \+ H2O ---> NH2COOH + NH3 (1) NH2COOH + H2O ---> NH3 \+ H2CO3 (2) Ammonium and carbonic acid form bicarbonate and 2 moles of ammonium and hydroxide ions in water (3 &4). 2NH3 \+ 2H2O <\---> 2NH+4 +2OH− (3) H2CO3 <\---> HCO−3 \+ H+ (4) The production of hydroxide ions results in the increase of pH , which in turn can shift the bicarbonate equilibrium, resulting in the formation of carbonate ions (5) HCO−3 \+ H+ \+ 2NH+4 +2OH− <\---> CO3−2 \+ 2NH+4 \+ 2H2O (5) The produced carbonate ions precipitate in the presence of calcium ions as calcium carbonate crystals (6).
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This enzyme acts as the second step of a biochemical pathway initiated by the creation of N-acylphosphatidylethanolamine, by means of the transfer of an acyl group from the sn-1 position of glycerophospholipid onto the amino group of phosphatidylethanolamine. While NAPE-PLD contributes to the biosynthesis of several NAEs in the mammalian central nervous system, it is not clear if this enzyme is not responsible for the formation of the endocannabinoid anandamide, since NAPE-PLD knockout mice have been reported to have wild-type levels or very reduced levels of anandamide. The N-acylethanolamines released by this enzyme become potential substrates for fatty acid amide hydrolase (FAAH), which hydrolyzes the free fatty acids from ethanolamine. Defects in this enzyme can cause NAPE-PLD products such as anandamide to build up to levels 15-fold higher than normally observed.
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Dimethyldichlorosilane hydrolyzes to form linear and cyclic silicones, compounds containing Si-O backbones. The length of the resulting polymer is dependent on the concentration of chain ending groups that are added to the reaction mixture. The rate of the reaction is determined by the transfer of reagents across the aqueous-organic phase boundary; therefore, the reaction is most efficient under turbulent conditions. The reaction medium can be varied further to maximize the yield of a specific product. :n(CH3)2SiCl2 \+ nH2O → [(CH3)2SiO]n \+ 2nHCl :m(CH3)2SiCl2 \+ (m+1)H2O → HO[Si(CH3)2O]mH + 2mHCl Dimethyldichlorosilane reacts with methanol to produce dimethoxydimethylsilanes. :(CH3)2SiCl2 \+ 2CH3OH → (CH3)2Si(OCH3)2 \+ 2HCl Although the hydrolysis of dimethoxydimethylsilanes is slower, it is advantageous when the hydrochloric acid byproduct is unwanted: :n(CH3)2Si(OCH3)2 \+ nH2O → [(CH3)2SiO]n \+ 2nCH3OH Because dimethyldichlorosilane is easily hydrolyzed, it cannot be handled in air.
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In order to disrupt these stable interactions, katanin, once bound to ATP, oligomerizes into a ring structure on the microtubule wall - in some cases oligomerization increases the affinity of katanin for microtubules and stimulates its ATPase activity. Once this structure is formed, katanin hydrolyzes ATP, and likely undergoes a conformational change that puts mechanical strain on the tubulin subunits, which destabilizes their interactions within the microtubule lattice. The predicted conformational change also likely decreases the affinity of katanin for tubulin as well as for other katanin proteins, which leads to disassembly of the katanin ring structure, and recycling of the individual inactivated proteins.Hartman, J. & Vale, R. (1999) Microtubule Disassembly by ATP-dependent Oligomerization of the AAA Enzyme Katanin The severing of microtubules by katanin is regulated by nucleotide exchange factors, which can exchange ADP with ATP, protective microtubule-associated proteins (MAPs), and the p80 subunit (p60 severs microtubules much better in the presence of p80).
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Trefoil (P-type) domain is a cysteine-rich domain of approximately forty five amino-acid residues has been found in some extracellular eukaryotic proteins. It is known as either the 'P', 'trefoil' or 'TFF' domain, and contains six cysteines linked by three disulphide bonds with connectivity 1-5, 2-4, 3-6. The domain has been found in a variety of extracellular eukaryotic proteins, including protein pS2 (TFF1) a protein secreted by the stomach mucosa; spasmolytic polypeptide (SP) (TFF2), a protein of about 115 residues that inhibits gastrointestinal motility and gastric acid secretion; intestinal trefoil factor (ITF) (TFF3); Xenopus laevis stomach proteins xP1 and xP4; xenopus integumentary mucins A.1 (preprospasmolysin) and C.1, proteins which may be involved in defense against microbial infections by protecting the epithelia from the external environment; xenopus skin protein xp2 (or APEG); Zona pellucida sperm-binding protein B (ZP-B); intestinal sucrase-isomaltase ( / ), a vertebrate membrane bound, multifunctional enzyme complex which hydrolyzes sucrose, maltose and isomaltose; and lysosomal alpha-glucosidase ().
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This rotated ribosomal intermediate, in which the first tRNA occupies a hybrid A/P position and the second tRNA occupies a hybrid P/E position is a substrate for EF-G-GTP. As a GTPase, EF-G binds to the rotated ribosome near the A site in its GTP-bound state, and hydrolyzes GTP, releasing GDP and inorganic phosphate: : GTP + H2O -> GDP + P_{i} The hydrolysis of GTP allows for a large conformational change within EF-G, forcing the A/P tRNA to fully occupy the P site, the P/E tRNA to fully occupy the E site (and exit the ribosome complex), and the mRNA to shift three nucleotides down relative to the ribosome. The GDP-bound EF-G molecule then dissociates from the complex, leaving another free A-site where the elongation cycle can start again. Crystal structure of the ribosome with two tRNAs (orange and green) and EF-G (in cyan) after translocation.
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