"Because glucose is the simplest form of sugar — a monosaccharide — it is the primary type that cells use," she explains.
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The Beginner's Guide to Pre and Post Workout Supplements Fructose Another monosaccharide, you'll find fructose in fruit, fruit juice, honey and vegetables.
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To determine the sugars within root mucilage, monosaccharide analysis and monosaccharide linkage analysis are undertaken. Monosaccharide linkage analysis involves methylating the root mucilage, which contains polysaccharides. The root mucilage is hydrolysed using acid to break down the polysaccharides into their monosaccharide components. The subsistent monosaccharides are then reduced to open their rings.
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In enzymology, an UTP-monosaccharide-1-phosphate uridylyltransferase () is an enzyme that catalyzes the chemical reaction :UTP + a monosaccharide 1-phosphate \rightleftharpoons diphosphate + UDP-monosaccharide Thus, the two substrates of this enzyme are UTP and monosaccharide 1-phosphate, whereas its two products are diphosphate and UDP-monosaccharide. This enzyme belongs to the family of transferases, specifically those transferring phosphorus- containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is '. Other names in common use include UDP-sugar pyrophosphorylase', and PsUSP.
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Catabolism is the metabolic reaction which cells undergo to break down larger molecules, extracting energy. There are two major metabolic pathways of monosaccharide catabolism: glycolysis and the citric acid cycle. In glycolysis, oligo- and polysaccharides are cleaved first to smaller monosaccharides by enzymes called glycoside hydrolases. The monosaccharide units can then enter into monosaccharide catabolism.
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In enzymology, a monosaccharide-transporting ATPase () is an enzyme that catalyzes the chemical reaction :ATP + H2O + monosaccharideout \rightleftharpoons ADP + phosphate + monosaccharidein The 3 substrates of this enzyme are ATP, H2O, and monosaccharide, whereas its 3 products are ADP, phosphate, and monosaccharide. This enzyme belongs to the family of hydrolases, specifically those acting on acid anhydrides to catalyse transmembrane movement of substances. The systematic name of this enzyme class is ATP phosphohydrolase (monosaccharide-importing). This enzyme participates in abc transporters - general.
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The legume lectins use an ingenious framework for binding specific sugars. This framework consists of a conserved monosaccharide binding site in which four conserved residues from four separate regions in the protein confer affinity (see figure), a variable loop that confers monosaccharide specificity and a number of subsites around the monosaccharide binding site that harbour additional sugar residues or hydrophobic groups.
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Carbohydrate synthesis is a sub-field of organic chemistry concerned specifically with the generation of natural and unnatural carbohydrate structures. This can include the synthesis of monosaccharide residues or structures containing more than one monosaccharide, known as oligosaccharides.
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Carbohydrate synthesis is a sub- field of organic chemistry concerned specifically with the generation of natural and unnatural carbohydrate structures. This can include the synthesis of monosaccharide residues or structures containing more than one monosaccharide, known as oligosaccharides.
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An octose is a monosaccharide containing eight carbon atoms. Lincomycin contains the octose methylthiolincosamide.
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Glycans can be homo- or heteropolymers of monosaccharide residues, and can be linear or branched.
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Galactose is a monosaccharide. When combined with glucose (monosaccharide), through a condensation reaction, the result is the disaccharide lactose. The hydrolysis of lactose to glucose and galactose is catalyzed by the enzymes lactase and β-galactosidase. The latter is produced by the lac operon in Escherichia coli.
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Polysaccharides are considered to be polymers of monosaccharides containing ten or more monosaccharide residues. Polysaccharides have been given trivial names that reflect their origin. Two common examples are cellulose, a main component of the cell wall in plants, and starch, a name derived from the Anglo-Saxon stercan, meaning to stiffen. To name a polysaccharide composed of a single type of monosaccharide, that is a homopolysaccharide, the ending “-ose” of the monosaccharide is replaced with “-an”.
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In addition to the factors affecting monosaccharide residues, conformational analysis of oligosaccharides and polysaccharides requires consideration additional factors.
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A ulonic acid is a carboxylic acid derived from a monosaccharide where the acid group is at position 1.
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Glycolaldehyde is the only diose A diose is a monosaccharide containing two carbon atoms. Because the general chemical formula of an unmodified monosaccharide is (C·H2O)n, where n is three or greater, it does not meet the formal definition of a monosaccharide. However, since it does fit the formula (C·H2O)n, it is sometimes thought of as the most basic sugar. There is only one possible diose, glycolaldehyde (2-hydroxyethanal), which is an aldodiose (a ketodiose is not possible since there are only two carbons).
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37, page 71. The protected monosaccharide was reacted with an organolithium sulfur compound and then catalytically hydrolyzed to produce -streptose.
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There are two types of strontium saccharide: one at low temperature, the strontium monosaccharide; and the second at high temperature, the strontium disaccharide.
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These side chains contain three monosaccharide residues. Xanthan lyase is produced by bacteria that degrade this polysaccharide, such as Bacillus, Corynebacterium and Paenibacillus species.
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A nonose is a monosaccharide with nine carbons.Paul G. Engelkirk and Gwendolyn R. Wilson Burton. (2006) Burton's microbiology for the health sciences, p. 92.
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The glycosidic bond can be formed between any hydroxyl group on the component monosaccharide. So, even if both component sugars are the same (e.g., glucose), different bond combinations (regiochemistry) and stereochemistry (alpha- or beta-) result in disaccharides that are diastereoisomers with different chemical and physical properties. Depending on the monosaccharide constituents, disaccharides are sometimes crystalline, sometimes water-soluble, and sometimes sweet-tasting and sticky-feeling.
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Several scientists have determined the composition of plant root mucilage using monosaccharide analysis and linkage analysis, showing that Maize (Zea mays) root mucilage contains high levels of galactose, xylose, arabinose, rhamnose, and glucose, and lower levels of uronic acid, mannose, fucose, and glucuronic acid. Wheat (Triticum aestivum) root mucilage also contains high levels of xylose, arabinose, galactose, glucose, and lower levels of rhamnose, glucuronic acid and mannose. Cowpea (Vigna unguiculata) also contains high levels of arabinose, galactose, glucose, fucose, and xylose, and lower levels of rhamnose, mannose, and glucuronic acid. Many other plants have had their root mucilage composition determined using monosaccharide analysis and monosaccharide linkage analysis.
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Tn antigen refers to the monosaccharide structure N-acetylgalactosamine (GalNAc) linked to serine or threonine by a glycosidic bond.I. Brockhausen, H. Schachter, P. Stanley, Essentials of Glycobiology, 2nd edition. A. Varki, R. Cummings, J. Esko, Eds, Cold Spring Harbor (NY): Cold Spring Harbor Laboratory Press; 2009. Chapter 9, O-GalNAc Glycans Addition of an additional galactose monosaccharide creates a disaccharide antigen: the Thomsen-Friedenreich antigen (Gal(b1-3)GalNAc).
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Polysaccharides are often quite heterogeneous, containing slight modifications of the repeating unit. Depending on the structure, these macromolecules can have distinct properties from their monosaccharide building blocks. They may be amorphous or even insoluble in water. When all the monosaccharides in a polysaccharide are the same type, the polysaccharide is called a homopolysaccharide or homoglycan, but when more than one type of monosaccharide is present they are called heteropolysaccharides or heteroglycans.
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Monosaccharides have heats of combustion of around 3.75 kcal/g (15.7 kJ/g), disaccharides 3.95 kcal/g (16.5 kJ/g) and polysaccharides 4.15 to 4.20 kcal/g (17.4 to 17.6 kJ/g). The heat of hydrolysis is very small and these values are essentially equivalent when calculated on a monosaccharide basis. Thus 100 g sucrose gives on hydrolysis 105.6 g monosaccharide and 100 g starch gives on hydrolysis 110 g glucose.
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In chemistry, a dialdose is a monosaccharide containing two aldehyde groups. For example, the hexodialdose O=CH–(CHOH)4–CH=O, obtained by reducing glucose with sodium amalgam.
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Topiramate is a derivative of the naturally occurring sugar monosaccharide D-fructose. Review articles characterize topiramate as showing "encouraging", "promising", "efficacious", and "insufficient" evidence in the treatment of alcohol use disorders.
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Sarmentose is a monosaccharide with the molecular formula C7H14O4 obtained from sarmentocymarin by hydrolysis. It is stereoisomeric with cymarose, and closely related to digitalose, which is obtained from digitalin by hydrolysis.
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Benjamin Cummings. Polysaccharides, meanwhile, have a general formula of Cx(H2O)y where x is usually a large number between 200 and 2500. When the repeating units in the polymer backbone are six-carbon monosaccharides, as is often the case, the general formula simplifies to (C6H10O5)n, where typically . As a rule of thumb, polysaccharides contain more than ten monosaccharide units, whereas oligosaccharides contain three to ten monosaccharide units; but the precise cutoff varies somewhat according to convention.
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Sucrose: ordinary table sugar and probably the most familiar carbohydrate. Comprising 75% of the biological world and 80% of all food intake for human consumption, the most common known human carbohydrate is Sucrose. The simplest version of a carbohydrate is a monosaccharide which contains carbon, hydrogen, and oxygen in a 1:2:1 ratio under a general formula of CnH2nOn where n is a minimum of 3. Glucose is an example of a monosaccharide as is fructose.
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For example, there are 16 distinct aldohexose stereoisomers, but the name "glucose" means a specific pair of mirror-image aldohexoses. In the Fischer projection, one of the two glucose isomers has the hydroxyl at left on C3, and at right on C4 and C5; while the other isomer has the reversed pattern. These specific monosaccharide names have conventional three-letter abbreviations, like "Glu" for glucose and "Thr" for threose. Generally, a monosaccharide with n asymmetrical carbons has 2n stereoisomers.
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A heptose is a monosaccharide with seven carbon atoms. They have either an aldehyde functional group in position 1 (aldoheptoses) or a ketone functional group in position 2, 3 or 4 (ketoheptoses).
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Altrose is an aldohexose sugar. D-Altrose is an unnatural monosaccharide. It is soluble in water and practically insoluble in methanol. However, L-altrose has been isolated from strains of the bacterium Butyrivibrio fibrisolvens.
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The pigments are composed mainly from chlorophyll a and b and the carotenoids violaxanthin, alloxanthin, monadoxanthin, neoxanthin, lutein, diatoxanthin and zeaxanthin. The cell wall is mainly composed of polymers of the monosaccharide arabinose, polyarabinose.
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For example, a glucose polymer is named glucan, a mannose polymer is named mannan, and a galactose polymer is named galactan. When the glycosidic linkages and configurations of the monosaccharides are known, they may be included as a prefix to the name, with the notation for glycosidic linkages preceding the symbols designating the configuration. The following example will help illustrate this concept: (1→4)-β-D-Glucan (1→4)-β-D-Glucan A heteropolysaccharide is a polymer containing more than one kind of monosaccharide residue. The parent chain contains only one type of monosaccharide and should be listed last with the ending “-an”, and the other types of monosaccharides listed in alphabetical order as “glyco-” prefixes. When there is no parent chain, all different monosaccharide residues are to be listed alphabetically as “glyco-” prefixes and the name should end with “-glycan”.
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2-3 drops of Barfoed's reagent is added to 1 mL of given sample in a test tube and boiled for 30 seconds and then allowed to cool. If a red precipitate occurs, a monosaccharide is present.
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The number of distinct stereoisomers with the same diagram is bounded by 2c, where c is the total number of chiral carbons. The Fischer projection is a systematic way of drawing the skeletal formula of an acyclic monosaccharide so that the handedness of each chiral carbon is well specified. Each stereoisomer of a simple open-chain monosaccharide can be identified by the positions (right or left) in the Fischer diagram of the chiral hydroxyls (the hydroxyls attached to the chiral carbons). Most stereoisomers are themselves chiral (distinct from their mirror images).
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The number of open chain stereoisomers for an aldose monosaccharide is larger by one than that of a ketose monosaccharide of the same length. Every ketose will have 2(n−3) stereoisomers where n > 2 is the number of carbons. Every aldose will have 2(n−2) stereoisomers where n > 2 is the number of carbons. These are also referred to as epimers which have the different arrangement of −OH and −H groups at the asymmetric or chiral carbon atoms (this does not apply to those carbons having the carbonyl functional group).
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A cord factor molecule is composed of a trehalose sugar, a disaccharide, that is esterified to two mycolic acid residues. One of the two mycolic acid residues is attached to the sixth carbon of one monosaccharide, while the other mycolic acid residue is attached to the sixth carbon of the other monosaccharide. Therefore, cord factor is also named trehalose-6,6'-dimycolate. The carbon chain of the mycolic acid residues vary in length depending on the species of bacteria it is found in, but the general range is 20 to 80 carbon atoms.
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Ribulose is a ketopentose -- a monosaccharide containing five carbon atoms, and including a ketone functional group. It has chemical formula 5105. Two enantiomers are possible, -ribulose (-erythro-pentulose) and -ribulose (-erythro-pentulose). -Ribulose is the diastereomer of -xylulose.
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Gibbons, Euell. 1962. Stalking the wild asparagus. David McKay, New York The tuber contains about 2% protein, no oil, and little starch. It is rich in the carbohydrate inulin (8 to 13%), which is a polymer of the monosaccharide fructose.
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The monosaccharide glucose plays a pivotal role in metabolism, where the chemical energy is extracted through glycolysis and the citric acid cycle to provide energy to living organisms. Some other monosaccharides can be converted in the living organism to glucose.
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Mannoheptulose is a heptose, a monosaccharide with seven carbon atoms, and a ketose, with the characteristic carbonyl group of the carbohydrate present on a secondary carbon (functioning as a ketone group). The sugar alcohol form of mannoheptulose is known as perseitol.
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185px 185px The α and β anomers of glucose. Note the position of the hydroxyl group (red or green) on the anomeric carbon relative to the CH2OH group bound to carbon 5: they either have identical absolute configurations (R,R or S,S) (α), or opposite absolute configurations (R,S or S,R) (β). Monosaccharides are classified according to three different characteristics: the placement of its carbonyl group, the number of carbon atoms it contains, and its chiral handedness. If the carbonyl group is an aldehyde, the monosaccharide is an aldose; if the carbonyl group is a ketone, the monosaccharide is a ketose.
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The general chemical formula of an unmodified monosaccharide is (C•H2O)n, literally a "carbon hydrate". Monosaccharides are important fuel molecules as well as building blocks for nucleic acids. The smallest monosaccharides, for which n=3, are dihydroxyacetone and D- and L-glyceraldehydes.
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Since acarbose and other alpha-glucosidase inhibitors prevent starch and other sugars from being broken down into monosaccharides that can be absorbed by the body, people taking these medications should consume monosaccharide-containing foods such as glucose tablets, honey, or juice to reverse hypoglycemia.
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Gulose is an aldohexose sugar. It is a monosaccharide that is very rare in nature, but has been found in archaea, bacteria and eukaryotes. It also exists as a syrup with a sweet taste. It is soluble in water and slightly soluble in methanol.
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In chemistry, a pentose is a monosaccharide (simple sugar) with five carbon atoms.Pentose, Merriam-Webster The chemical formula of all pentoses is , and their molecular weight is 150.13 g/mol."-Ribose". PubChem compound webpage, accessed on 2010-02-06. Pentoses are very important in biochemistry.
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D-Psicose (C6H12O6), also known as D-allulose, or simply allulose, is a low- calorie monosaccharide sugar used by some major commercial food and beverage manufacturers. First identified in wheat more than 70 years ago, allulose is naturally present in small quantities in certain foods.
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Idose is a hexose, a six carbon monosaccharide. It has an aldehyde group and is an aldose. It is not found in nature, but its uronic acid, iduronic acid, is important. It is a component of dermatan sulfate and heparan sulfate, which are glycosaminoglycans.
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Xylulose is a ketopentose, a monosaccharide containing five carbon atoms, and including a ketone functional group. It has the chemical formula 5105. In nature, it occurs in both the L\- and D-enantiomers. 1-Deoxyxylulose is a precursor to terpenes via the nonmevalonic acid pathway.
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G3P is generally considered the prime end-product of photosynthesis and it can be used as an immediate food nutrient, combined and rearranged to form monosaccharide sugars, such as glucose, which can be transported to other cells, or packaged for storage as insoluble polysaccharides such as starch.
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Fructose, an example of a ketose. The ketone group is the double- bonded oxygen. A ketose is a monosaccharide containing one ketone group per molecule. The simplest ketose is dihydroxyacetone, which has only three carbon atoms, and it is the only one with no optical activity.
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Lyxose is an aldopentose -- a monosaccharide containing five carbon atoms, and including an aldehyde functional group. It has chemical formula 5105. It is a C'-2 carbon epimer of the sugar xylose. Lyxose occurs only rarely in nature, for example, as a component of bacterial glycolipids.
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This method results in oligogalacturonides. Exo-PGs hydrolyze at the non-reducing end of the polymer, generating a monosaccharide galacturonic acid. Occasionally, organisms employ both methods. In addition to different modes of action, PG polymorphism allows fungal PGs to more effectively degrade a wider range of plant tissues.
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Dithioerythritol (DTE) is a sulfur containing sugar derived from the corresponding 4-carbon monosaccharide erythrose. It is an epimer of dithiothreitol (DTT). The molecular formula for DTE is C4H10O2S2. Like DTT, DTE makes an excellent reducing agent, although its standard reduction potential is not quite as negative, i.e.
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Monosaccharides are the simplest form of carbohydrates with only one simple sugar. They essentially contain an aldehyde or ketone group in their structure. The presence of an aldehyde group in a monosaccharide is indicated by the prefix aldo-. Similarly, a ketone group is denoted by the prefix keto-.
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Periodic acid Periodic acid–Schiff (PAS) is a staining method used to detect polysaccharides such as glycogen, and mucosubstances such as glycoproteins, glycolipids and mucins in tissues. The reaction of periodic acid oxidizes the vicinal diols in these sugars, usually breaking up the bond between two adjacent carbons not involved in the glycosidic linkage or ring closure in the ring of the monosaccharide units that are parts of the long polysaccharides, and creating a pair of aldehydes at the two free tips of each broken monosaccharide ring. The oxidation condition has to be sufficiently regulated so as to not oxidize the aldehydes further. These aldehydes then react with the Schiff reagent to give a purple-magenta color.
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Xylose (cf. , xylon, "wood") is a sugar first isolated from wood, and named for it. Xylose is classified as a monosaccharide of the aldopentose type, which means that it contains five carbon atoms and includes an aldehyde functional group. It is derived from hemicellulose, one of the main constituents of biomass.
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Structures and distribution of glycolaldehyde as a 20% solution in water. Notice that the free aldehyde is a minor component. It is the only possible diose, a 2-carbon monosaccharide, although a diose is not strictly a saccharide. While not a true sugar, it is the simplest sugar-related molecule.
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It must be taken at the start of main meals to have maximal effect. Its effect will depend on the amount of non- monosaccharide carbohydrates in a person's diet. In contrast to acarbose (another alpha-glucosidase inhibitor), miglitol is systemically absorbed; however, it is not metabolized and is excreted by the kidneys.
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Allose is an aldohexose sugar. It is a rare monosaccharide that occurs as a 6-O-cinnamyl glycoside in the leaves of the African shrub Protea rubropilosa. Extracts from the fresh-water alga Ochromas malhamensis contain this sugar but of unknown absolute configuration. It is soluble in water and practically insoluble in methanol.
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NagA Pathway in BacteriaNagA is located in the cytoplasm of the cell. N-acetylglucosamine (GlcNAc) enters the cell as part of the breakdown of the cell wall. GlcNAc, a monosaccharide and derivative of glucose, is part of a biopolymer in the bacterial cell wall. This biopolymer forms a layered structure called peptidoglycan (PG).
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All monosaccharide ketoses are reducing sugars, because they can tautomerize into aldoses via an aldol intermediate, and the resulting aldehyde group can be oxidised, for example in the Tollens' test or Benedict's test. Ketoses that are bound into glycosides, for example in the case of the fructose moiety of sucrose, are nonreducing sugars.
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Glyceraldehyde (glyceral) is a triose monosaccharide with chemical formula C3H6O3. It is the simplest of all common aldoses. It is a sweet, colorless, crystalline solid that is an intermediate compound in carbohydrate metabolism. The word comes from combining glycerol and aldehyde, as glyceraldehyde is glycerol with one alcohol group oxidized to an aldehyde.
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GM3 is the most common membrane-bound glycosphingolipid in tissues, composed of three monosaccharide groups attached to a ceramide backbone. GM3 serves as a precursor for other, more complex gangliosides. Like other gangliosides, GM3 is synthesized in the Golgi apparatus. It is then transported to the plasma membrane, where it functions in cellular signaling.
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Most of the fructose and galactose travel to the liver, where they can be converted to glucose. Some simple carbohydrates have their own enzymatic oxidation pathways, as do only a few of the more complex carbohydrates. The disaccharide lactose, for instance, requires the enzyme lactase to be broken into its monosaccharide components, glucose and galactose.
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Talose is an aldohexose sugar. It is an unnatural monosaccharide that is soluble in water and slightly soluble in methanol. Some etymologists suggest that talose's name derives from the automaton of Greek mythology named Talos, but the relevance is unclear. Talose is a C-2 epimer of galactose and a C-4 epimer of mannose.
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If a patient using an alpha- glucosidase inhibitor suffers from an episode of hypoglycemia, the patient should eat something containing monosaccharides, such as glucose tablets. Since the drug will prevent the digestion of polysaccharides (or non- monosaccharides), non-monosaccharide foods may not effectively reverse a hypoglycemic episode in a patient taking an alpha-glucosidase inhibitor.
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Transferrin is a serum protein that carries iron through the bloodstream to the bone marrow, where red blood cells are manufactured, as well as to the liver and spleen. Structurally, transferrin is a polypeptide with two N-linked polysaccharide chains. These polysaccharide chains are branched with sialic acid residues. Sialic acid is a monosaccharide carbohydrate.
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The active site serves as the location where an enzyme and substrate bind and an enzymatic reaction can occur. The active site has three potential components: the pocket, the cleft, and the tunnel. The pocket structure is beneficial for recognition of monosaccharide like glucose. The cleft is allows for binding of sugars to form polysaccharides.
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The majority of oligosaccharides found in IMO consist of three to six monosaccharide (glucose) units linked together. However, disaccharides, as well as longer polysaccharides (up to nine glucose units), are also present. The disaccharide fraction of IMO consists mainly of α(1,6)-linked isomaltose, while maltotriose, panose, and isomaltotriose make up the trisaccharide fraction.
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Although E332 is located farther away from the anomeric carbon, the lower activity of Dispersin B with the mutation E332Q suggests that it is important for catalysis. It may be critical in stabilizing the transition state of cleaving the terminal monosaccharide. : Active Site of Dispersin B: E184 shown in blue. D183 shown in pink.
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The sugar group is then known as the glycone and the non-sugar group as the aglycone or genin part of the glycoside. The glycone can consist of a single sugar group (monosaccharide) or several sugar groups (oligosaccharide). The first glycoside ever identified was amygdalin, by the French chemists Pierre Robiquet and Antoine Boutron-Charlard, in 1830.
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D-xylose absorption test is a medical test performed to diagnose conditions that present with malabsorption of the proximal small intestine due to defects in the integrity of the gastrointestinal mucosa.D-xylose absorption MedlinePlus. Accessed 19 Dec 2012. D-xylose is a monosaccharide, or simple sugar, that does not require enzymes for digestion prior to absorption.
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An aldose is a monosaccharide (a simple sugar) with a carbon backbone chain with a carbonyl group on the endmost carbon atom, making it an aldehyde, and hydroxyl groups connected to all the other carbon atoms. Aldoses can be distinguished from ketoses, which have the carbonyl group away from the end of the molecule, and are therefore ketones.
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Sucrose. The glycoside bond is represented by the central oxygen atom, which holds the two monosaccharide units together. Monosaccharides can be linked together by glycosidic bonds, which can be cleaved by hydrolysis. Two, three, several or many monosaccharides thus linked form disaccharides, trisaccharides, oligosaccharides, or polysaccharides, respectively. Enzymes that hydrolyse glycosidic bonds are called "glycoside hydrolases" or "glycosidases".
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In a Fischer projection, all horizontal bonds are meant to be slanted toward the viewer. Molecules with a simple tetrahedral geometry can be easily rotated in space, so that this condition is met (see figures). For instance, a monosaccharide with three carbon atoms (triose), such as the D-Glyceraldehyde depicted above has a tetrahedral geometry, with C2 at its center, and can be rotated in space so that the carbon chain is vertical with C1 at the top, and the horizontal bonds connecting C2 with -H and -OH are both slanted toward the viewer. However, when creating a Fischer projection for a monosaccharide with more than three carbons, there's no way to orient the molecule in space so that all horizontal bonds will be slanted toward the viewer.
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Glucose is a simple sugar with the molecular formula . Glucose is the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using energy from sunlight, where it is used to make cellulose in cell walls, which is the most abundant carbohydrate.Kenji Kamide: Cellulose and Cellulose Derivatives.
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They are long chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages. This carbohydrate can react with water (hydrolysis) using amylase enzymes as catalyst, which produces constituent sugars (monosaccharides, or oligosaccharides). They range in structure from linear to highly branched. Examples include storage polysaccharides such as starch, glycogen and galactogen and structural polysaccharides such as cellulose and chitin.
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Saccharification is any event wherein a monosaccharide molecule remains intact after becoming unbound to another saccharide that it was attached to. Amylases (partially constituting saliva secreted within the mouth) and brush border enzymes (within the small intestine) are able to perform exact saccharification through enzymatic hydrolysis. Through thermolysis, saccharification can also occur as a transient result, amongst many other possible effects, during caramelization.
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A deoxyribonucleotide is a nucleotide that contains deoxyribose. They are the monomeric units of the informational biopolymer, deoxyribonucleic acid (DNA). Each deoxyribonucleotide comprises three parts: a deoxyribose sugar (monosaccharide), a nitrogenous base, and one phosphoryl group. The nitrogenous bases are either purines or pyrimidines, heterocycles whose structures support the specific base-pairing interactions that allow nucleic acids to carry information.
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The gut of bees is relatively simple, but multiple metabolic strategies exist in the gut microbiota. Pollinating bees consume nectar and pollen, which require different digestion strategies by somewhat specialized bacteria. While nectar is a liquid of mostly monosaccharide sugars and so easily absorbed, pollen contains complex polysaccharides: branching pectin and hemicellulose. Approximately five groups of bacteria are involved in digestion.
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When xylose and fufural are the goal, acid catalysts, such as formic acid, are added to increase the transition of polysaccharide to monosaccharide. This catalyst also has been show to also utilize a solvent effect to be aid the reaction. One method of pretreatment is to soak the wood with diluted acids (with concentrations around 4%). This converts the hydroloze hemicellulose into monosaccharaides.
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Monosaccharides can be linked together into what are called polysaccharides (or oligosaccharides) in a large variety of ways. Many carbohydrates contain one or more modified monosaccharide units that have had one or more groups replaced or removed. For example, deoxyribose, a component of DNA, is a modified version of ribose; chitin is composed of repeating units of N-acetyl glucosamine, a nitrogen- containing form of glucose.
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An example of an O-linked oligosaccharide with β-Galactosyl-(1n3)-α-N-acetylgalactosaminyl-Ser/Thr. Oligosaccharides that participate in O-linked glycosylation are attached to threonine or serine on the hydroxyl group of the side chain. O-linked glycosylation occurs in the Golgi apparatus, where monosaccharide units are added to a complete polypeptide chain. Cell surface proteins and extracellular proteins are O-glycosylated.
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N-Acetylmuramic acid, "NAM" or MurNAc, is the addition of phosphoenolpyruvate and N-acetylglucosamine with the chemical formula . It is a key builder of peptidoglycan in the bacterial cell wall, which is built from alternating units of N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc), cross-linked by oligopeptides at the lactic acid residue of MurNAc. MurNAc is a monosaccharide derivative of N-acetylglucosamine.
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N-Acetylmannosamine is a hexosamine monosaccharide. It is a neutral, stable naturally occurring compound. N-Acetylmannosamine is also known as N-Acetyl-D- mannosamine monohydrate, (which has the CAS Registry Number: 676347-48-1), N-Acetyl-D-mannosamine which can be abbreviated to ManNAc or, less commonly, NAM). ManNAc is the first committed biological precursor of N-acetylneuraminic acid (Neu5Ac, sialic acid) (Figure 1).
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N-Acetylglucosamine molecule N-Acetylglucosamine (GlcNAc) is an amide derivative of the monosaccharide glucose. It is a secondary amide between glucosamine and acetic acid. It is significant in several biological systems. It is part of a biopolymer in the bacterial cell wall, which is built from alternating units of GlcNAc and N-acetylmuramic acid (MurNAc), cross-linked with oligopeptides at the lactic acid residue of MurNAc.
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Fig fruits, especially the exocarp (skin) and seeds, contain monosaccharide sugars and mixed phytochemicals, such as flavonoids, gallic acid, chlorogenic acid, rutin, and epicatechins, the contents of which are higher in dark figs compared to those in light-colored varieties. Ripe fruits contain higher amounts of polyphenols and sugar than unripe fruits, and drying generally increases the contents of these constituents per unit of weight.
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In that case, mirroring is equivalent to a half-turn rotation. For this reason, there are only three distinct 3-ketopentose stereoisomers, even though the molecule has two chiral carbons. Distinct stereoisomers that are not mirror-images of each other usually have different chemical properties, even in non-chiral environments. Therefore, each mirror pair and each non-chiral stereoisomer may be given a specific monosaccharide name.
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The −OH group that replaces the carbonyl's oxygen may end up in two distinct positions relative to the ring's midplane. Thus each open-chain monosaccharide yields two cyclic isomers (anomers), denoted by the prefixes α- and β-. The molecule can change between these two forms by a process called mutarotation, that consists in a reversal of the ring-forming reaction followed by another ring formation.
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Stp4 (sugar transporter protein 4) is a gene from the model plant, Arabidopsis thaliana. The gene transcribes for an integral membrane protein that is situated in the plasma membrane of sink tissues such as roots, anthers and vascular tissue. The protein's function is to transport monosaccharide sugars into these sink tissues. The protein is classed as a symporter since sodium ions are also transported concurrently in the same direction.
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The designations KSI and KSII were originally assigned on the basis of the tissue type from which the keratan sulfate was isolated. KSI was isolated from corneal tissue and KSII from skeletal tissue. Minor monosaccharide compositional differences exist between KS extracted from both sources and even KS extracted from the same source. However, major differences occur in the way each KS type is joined to its core protein.
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Smaller nanoparticles were formed at high pH levels due to the concentration of the monosaccharides. Another method of silver nanoparticle synthesis includes the use of reducing sugars with alkali starch and silver nitrate. The reducing sugars have free aldehyde and ketone groups, which enable them to be oxidized into gluconate. The monosaccharide must have a free ketone group because in order to act as a reducing agent it first undergoes tautomerization.
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29% - 54% of fructose is converted in liver to glucose, and about a quarter of fructose is converted to lactate. 15% - 18% is converted to glycogen. Glucose and lactate are then used normally as energy to fuel cells all over the body. Fructose is a dietary monosaccharide present naturally in fruits and vegetables, either as free fructose or as part of the disaccharide sucrose, and as its polymer inulin.
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Xylose D-Xylose is a five-carbon aldose (pentose, monosaccharide) that can be catabolized or metabolized into useful products by a variety of organisms. There are at least four different pathways for the catabolism of D-xylose: An oxido-reductase pathway is present in eukaryotic microorganisms. Prokaryotes typically use an isomerase pathway, and two oxidative pathways, called Weimberg and Dahms pathways respectively, are also present in prokaryotic microorganisms.
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Oat beta-glucan is a viscous polysaccharide made up of units of the monosaccharide D-glucose. Oat beta- glucan is composed of mixed-linkage polysaccharides. This means the bonds between the D-glucose or D-glucopyranosyl units are either beta-1, 3 linkages or beta-1, 4 linkages. This type of beta-glucan is also referred to as a mixed-linkage (1→3), (1→4)-beta-D-glucan.
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The biosynthesis of sucrose proceeds via the precursors UDP-glucose and fructose 6-phosphate, catalyzed by the enzyme sucrose-6-phosphate synthase. The energy for the reaction is gained by the cleavage of uridine diphosphate (UDP). Sucrose is formed by plants, algae and cyanobacteria but not by other organisms. Sucrose is the end product of photosynthesis and is found naturally in many food plants along with the monosaccharide fructose.
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Allulose, also known by its systematic name D-ribo-2-hexulose as well as by the name D-psicose, is a monosaccharide and a ketohexose. It is a C3 epimer of fructose. Fructose can be converted to allulose by the enzyme D-tagatose 3-epimerase, which has allowed for mass production of allulose. The compound is found naturally in trace amounts in wheat, figs, raisins, maple syrup, and molasses.
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The β-D-glucopyranosyl group which is obtained by the removal of the hemiacetal hydroxyl group from β-D-glucopyranose A glycosyl group is a univalent free radical or substituent structure obtained by removing the hemiacetal hydroxyl group from the cyclic form of a monosaccharide and, by extension, of a lower oligosaccharide. Glycosyl also reacts with inorganic acids, such as phosphoric acid, forming an ester such as glucose 1-phosphate.
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Tagatose is monosaccharide within the hexose class. A white solid, it is rare in nature but has attracted attention as an artificial sweetener. It is often found in dairy products, and is very similar in texture to sucrose (table sugar) and is 92% as sweet, but with only 38% of the calories. Tagatose is generally recognized as safe (GRAS) by the FAO/WHO and has been since 2001.
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Chondroitin sulfate proteoglycans are composed of a core protein and a sugar side chain. The core protein is generally a glycoprotein, and the side chains are glycosaminoglycan (GAG) sugar chains attached through a covalent bond. The GAG side chains are of different lengths depending on the CSPG. Each GAG chain consists of a linear pattern of alternating monosaccharide units: uronic acid and either N-acetylglucosamine or N-acetylgalactosamine.
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Rebaudioside A (sometimes shortened to "Reb A") is a steviol glycoside that is 240 times sweeter than sugar. The glycoside contains only glucose (to the exclusion of other commonly found monosaccharides) as its monosaccharide moieties. It contains four glucose molecules in total with the central glucose of the triplet connected to the main steviol structure at its hydroxyl group, and the remaining glucose at its carboxyl group forming an ester bond.
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The naturally occurring form of glucose is -glucose, while -glucose is produced synthetically in comparatively small amounts and is of lesser importance. Glucose is a monosaccharide containing six carbon atoms and an aldehyde group, and is therefore an aldohexose. The glucose molecule can exist in an open-chain (acyclic) as well as ring (cyclic) form. Glucose is naturally occurring and is found in fruits and other parts of plants in its free state.
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However, extensive root colonization still occurs in these plants and these hallmarks of resistance seem to diminish by about day 21 after colonization, implying that EcM fungi can suppress the defense response. As the fungus and plant become closely connected, they begin to share nutrients. This process is also controlled by symbiosis-related genes. For example, monosaccharide uptake in Amanita muscaria requires a transporter that is only expressed when it is in a mycorrhizal association.
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Monosaccharide nomenclature is the naming conventions of the basic unit of carbohydrate structure, monosaccharides, which may be monomers or part of a larger polymer. Monosaccharides are subunits that cannot be further hydrolysed in to simpler units. Depending on the number of carbon atom they are further classified in to trioses, tetroses, pentoses, hexoses etc., which is further classified in to aldoses and ketoses depending on the type of functional group present in them.
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SHBG has both enhancing and inhibiting hormonal influences. It decreases with high levels of insulin, growth hormone, insulin- like growth factor 1 (IGF-1), androgens, prolactin and transcortin. High estrogen and thyroxine levels cause it to increase. In an effort to explain obesity-related reductions in SHBG, recent evidence suggests sugar or monosaccharide-induced hepatic lipogenesis, hepatic lipids in general, and cytokines like TNF-alpha and Interleukin reduce SHBG, whereas insulin does not.
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Galactose (, galacto- + -ose, "milk sugar") sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epimer of glucose. A galactose molecule linked with a glucose molecule forms a lactose molecule. Galactan is a polymeric form of galactose found in hemicellulose, and forming the core of the galactans, a class of natural polymeric carbohydrates.
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The double bond of a glycal allows many other functional groups to be introduced into a monosaccharide. Like an alkene, a glycal can undergo electrophilic addition across the double bond to add in these new atoms such as halogens, epoxides, and nitrogen. The glycal double bond also allows a deoxy position (carbon in the ring that doesn’t have an oxygen bonded to it) to be easily introduced. Glycals have many uses in synthetic carbohydrate chemistry.
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Sulfoquinovose, also known as 6-sulfoquinovose and 6-deoxy-6-sulfo-D- glucopyranose, is a monosaccharide sugar that is found as a building block in the sulfolipid sulfoquinovosyl diacylglycerol (SQDG). Sulfoquinovose is a sulfonic acid derivative of glucose, the sulfonic acid group is introduced into the sugar by the enzyme UDP-sulfoquinovose synthase (SQD1). Sulfoquinovose is degraded through a metabolic process termed sulfoglycolysis. The half-life for mutarotation of sulfoquinovose at pD 7.5 and 26C is 299 minutes.
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In these early stages of infection, proteins are released by the infection vesicle which suppress the host's defense responses. One such protein is formed by the nitrogen starvation-induced gene CgDN3. The proteins suppress any hypersensitivity responses from the host to allow unhindered growth and development of the fungus. During the biotrophic phase, the pathogen gains nutrients by transferring hexoses and amino acids from the living host cell to the fungus by use of monosaccharide-H+ symporters.
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In humans it is the terminal carbohydrate forming the antigen of blood group A. It is typically the first monosaccharide that connects serine or threonine in particular forms of protein O-glycosylation. N-Acetylgalactosamine is necessary for intercellular communication, and is concentrated in sensory nerve structures of both humans and animals. GalNAc is also used as a targeting ligand in investigational antisense oligonucleotides and siRNA therapies targeted to the liver, where it binds to the asialoglycoprotein receptors on hepatocytes.
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Barfoed's test is a chemical test used for detecting the presence of monosaccharides. It is based on the reduction of copper(II) acetate to copper(I) oxide (Cu2O), which forms a brick-red precipitate. ::RCHO + 2Cu2+ \+ 2H2O → RCOOH + Cu2O↓ + 4H+ (Disaccharides may also react, but the reaction is much slower.) The aldehyde group of the monosaccharide which normally forms a cyclic hemiacetal is oxidized to the carboxylate. A number of other substances, including sodium chloride, may interfere.
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A monosaccharide often switches from the acyclic (open- chain) form to a cyclic form, through a nucleophilic addition reaction between the carbonyl group and one of the hydroxyls of the same molecule. The reaction creates a ring of carbon atoms closed by one bridging oxygen atom. The resulting molecule has a hemiacetal or hemiketal group, depending on whether the linear form was an aldose or a ketose. The reaction is easily reversed, yielding the original open-chain form.
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Natto was known to be a sort of superfood which promoted health and longevity in Japan during the late 1800s. In 1881, Lippmann first discovered "lävulan" (levan) as the remaining gum from molasses produced in the sugar beet companies. Later on in 1901, Greig-Smith coined the name “levan” based on the levorotatory properties of this substance in polarized light. This polymer is made up of fructose, a monosaccharide sugar, connected in 2,6 beta glycosidic linkages.
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In his 50-year career, Ferrier published 180 papers, reviews and books, and gave 10 invited plenary lectures at international symposia.A full list of publications is available from the Royal Society of New Zealand website. His reviews were of particular benefit to the chemical community but perhaps of most value was the book "Monosaccharide Chemistry, written with Dr Peter Collins in 1972 and majorly updated as "Monosaccharides: Their chemistry and their roles in natural products in 1995.
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In chemistry, a hexose is a monosaccharide (simple sugar) with six carbon atoms. The chemical formula for all hexoses is C6H12O6, and their molecular weight is 180.156 g/mol. Hexoses exist in two forms, open-chain or cyclic, that easily convert into each other in aqueus solutions. The open-chain form of a hexose, which usually is facoured in solutions, has the general structure H–(CHOH)n−1–C(=O)–(CHOH)4−n–H, where n is 1, 2, or 3.
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Deoxyribose, or more precisely 2-deoxyribose, is a monosaccharide with idealized formula H−(C=O)−(CH2)−(CHOH)3−H. Its name indicates that it is a deoxy sugar, meaning that it is derived from the sugar ribose by loss of an oxygen atom. Since the pentose sugars arabinose and ribose only differ by the stereochemistry at C2′, 2-deoxyribose and 2-deoxyarabinose are equivalent, although the latter term is rarely used because ribose, not arabinose, is the precursor to deoxyribose.
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Structure of the saccharolipid Kdo2-lipid A. Glucosamine residues in blue, Kdo residues in red, acyl chains in black and phosphate groups in green. Saccharolipids describe compounds in which fatty acids are linked directly to a sugar backbone, forming structures that are compatible with membrane bilayers. In the saccharolipids, a monosaccharide substitutes for the glycerol backbone present in glycerolipids and glycerophospholipids. The most familiar saccharolipids are the acylated glucosamine precursors of the Lipid A component of the lipopolysaccharides in Gram-negative bacteria.
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The deamination reaction, and therefore chain cleavage, is regardless of O-sulfation carried by either monosaccharide unit. At low pH, deaminative cleavage results in the release of inorganic SO4, and the conversion of GlcNS into anhydromannose (aMan). Low-pH nitrous acid treatment is an excellent method to distinguish N-sulfated polysaccharides such as heparin and HS from non N-sulfated polysacchrides such as chondroitin sulfate and dermatan sulfate, chondroitin sulfate and dermatan sulfate not being susceptible to nitrous acid cleavage.
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Lactulose is used in the treatment of chronic constipation in patients of all ages as a long- term treatment. The dosage of lactulose for chronic idiopathic constipation is adjusted depending on the constipation severity and desired effect, from a mild stool softener to causing diarrhea. Dosage is reduced in case of galactosemia, as most preparations contain the monosaccharide galactose due to its synthesis process. Lactulose may be used to counter the constipating effects of opioids, and in the symptomatic treatment of hemorrhoids as a stool softener.
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In enzymology, a poly(beta-D-mannuronate) lyase () is an enzyme that catalyzes the degradation of alginate into various monosaccharide and polysaccharide products. Alginate lyase cleaves the glycosidic bonds of alginate via a β-elimination mechanism, in which it first converts alginate into several oligosccharides containing unsaturated uronic acids at their non-reducing ends. It then cleaves the oligosaccharides, forming 4-deosy-L- erythro-5-hexoseulose uronic acid. This enzyme belongs to the family of lyases, specifically those carbon-oxygen lyases acting on polysaccharides.
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However, some biological substances commonly called "monosaccharides" do not conform to this formula (e.g. uronic acids and deoxy-sugars such as fucose) and there are many chemicals that do conform to this formula but are not considered to be monosaccharides (e.g. formaldehyde CH2O and inositol (CH2O)6). The open-chain form of a monosaccharide often coexists with a closed ring form where the aldehyde/ketone carbonyl group carbon (C=O) and hydroxyl group (–OH) react forming a hemiacetal with a new C–O–C bridge.
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Ascorbic acid or vitamin C is a monosaccharide oxidation-reduction (redox) catalyst found in both animals and plants. As one of the enzymes needed to make ascorbic acid has been lost by mutation during primate evolution, humans must obtain it from their diet; it is therefore a dietary vitamin. Most other animals are able to produce this compound in their bodies and do not require it in their diets. Ascorbic acid is required for the conversion of the procollagen to collagen by oxidizing proline residues to hydroxyproline.
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From PLOD2 two splice variant can be expressed (LH2a and LH2b), where LH2b differs from LH2a by incorporating the small exon 13A. LH1 and LH3 hydroxylate lysyl residues in the collagen triple helix, whereas LH2b hydroxylates lysyl residues in the telopeptides of collagen. In addition to its hydroxylation activity, LH3 has glycosylation activity that produces either monosaccharide (Gal) or disaccharide (Glc-Gal) attached to collagen hydroxylysines. Collagen lysyl hydroxylation is the first step in collagen pyridinoline cross-linking, that is necessary for the stabilization of collagen.
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The cells range in shape from egg-shaped, ellipsoidal, to elongated, measuring 2.5–5.0 by 5.0–15.0 µm, and occurring singly, doubly, or in groups of four. Asymmetrical blastoconidia are borne on short sterigmata, and measure 2.0–5.0 by 3.0–7.0 µm. The optimal growth temperature for the fungus occurs at a range of ; growth stops at . Like other Sporobolomyces species, S. koalae has coenzyme Q10 as its major ubiquinone, it lacks the monosaccharide xylose in whole-cell hydrolysates, and it cannot ferment sugars.
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Chemical structure of lipid A as found in E. Coli Saccharolipids describe compounds in which fatty acids are linked directly to a sugar backbone, forming structures that are compatible with membrane bilayers. In the saccharolipids, a monosaccharide substitutes for the glycerol backbone present in glycerolipids and glycerophospholipids. The most familiar saccharolipids are the acylated glucosamine precursors of the lipid A component of the lipopolysaccharides in Gram-negative bacteria. Typical lipid A molecules are disaccharides of glucosamine, which are derivatized with as many as seven fatty-acyl chains.
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One method of reducing the volume of flatus produced is dietary modification, reducing the amount of fermentable carbohydrates. This is the theory behind diets such as the low-FODMAP diet (low fermentable oligosaccharide, disacharide, monosaccharide and polyols). Certain spices have been reported to counteract the production of intestinal gas, most notably the closely related cumin, coriander, caraway, fennel and others such as ajwain, turmeric, asafoetida (hing), epazote, and kombu kelp (a Japanese seaweed). Most starches, including potatoes, corn, noodles, and wheat, produce gas as they are broken down in the large intestine.
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Carbohydrate metabolism denotes the various biochemical processes responsible for the formation, breakdown and interconversion of carbohydrates in living organisms. The most important carbohydrate is glucose, a simple sugar (monosaccharide) that is metabolized by nearly all known organisms. Glucose and other carbohydrates are part of a wide variety of metabolic pathways across species: plants synthesize carbohydrates from carbon dioxide and water by photosynthesis storing the absorbed energy internally, often in the form of starch or lipids. Plant components are consumed by animals and fungi, and used as fuel for cellular respiration.
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Selenium may be measured in blood, plasma, serum or urine to monitor excessive environmental or occupational exposure, confirm a diagnosis of poisoning in hospitalized victims or to assist in a forensic investigation in a case of fatal overdosage. Some analytical techniques are capable of distinguishing organic from inorganic forms of the element. Both organic and inorganic forms of selenium are largely converted to monosaccharide conjugates (selenosugars) in the body prior to being eliminated in the urine. Cancer patients receiving daily oral doses of selenothionine may achieve very high plasma and urine selenium concentrations.
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HA plays two key functions in viral entry. Firstly, it allows the recognition of target vertebrate cells, accomplished through the binding to these cells' sialic acid-containing receptors. Secondly, once bound it facilitates the entry of the viral genome into the target cells by causing the fusion of host endosomal membrane with the viral membrane. Specifically, the HA1 domain of the protein binds to the monosaccharide sialic acid which is present on the surface of its target cells, allowing attachment of viral particle to the host cell surface.
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A 2D diagram of an N-glycan linked to an antibody fragment in the structure with PDB accession code '4BYH'. This diagram, which has been generated with Privateer, follows the standard symbol nomenclature and includes, in its original svg format, annotations containing validation information, including ring conformation and detected monosaccharide types. The branched and cyclic nature of carbohydrates poses particular problems to structure validation tools. At higher resolutions, it is possible to determine the sequence/structure of oligo- and poly-saccharides, both as covalent modifications and as ligands.
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Villi increase the internal surface area of the intestinal walls making available a greater surface area for absorption. An increased absorptive area is useful because digested nutrients (including monosaccharide and amino acids) pass into the semipermeable villi through diffusion, which is effective only at short distances. In other words, increased surface area (in contact with the fluid in the lumen) decreases the average distance travelled by nutrient molecules, so effectiveness of diffusion increases. The villi are connected to the blood vessels so the circulating blood then carries these nutrients away.
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The absorption capacity for fructose in monosaccharide form ranges from less than 5 g to 50 g (per individual serving) and adapts with changes in dietary fructose intake. Studies show the greatest absorption rate occurs when glucose and fructose are administered in equal quantities. When fructose is ingested as part of the disaccharide sucrose, absorption capacity is much higher because fructose exists in a 1:1 ratio with glucose. It appears that the GLUT5 transfer rate may be saturated at low levels, and absorption is increased through joint absorption with glucose.
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The open ring monosaccharides are then acetylated, and separated typically by using gas chromatography, although liquid chromatography is also used. The masses of the monosaccharides are then detected using mass spectrometry. The gas chromatography retention times and the mass spectrometry chromatogram are used to identify how the monosaccharides are linked to form the polysaccharides that make root mucilage. For monosaccharide analysis, which reveals the sugars that make root mucilage, scientists hydrolyse the root mucilage using acid, and put the samples directly through gas chromatography linked to mass spectrometry.
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Maltose is a disaccharide: the carbohydrates are generally divided into monosaccharides, oligosaccharides, and polysaccharides depending on the number of sugar subunits. Maltose, with two sugar units, is an oligosaccharide, specifically a disaccharide, because it consists of two glucose molecules. Glucose is a hexose: a monosaccharide containing six carbon atoms. The two glucose units are in the pyranose form and are joined by an O-glycosidic bond, with the first carbon (C1) of the first glucose linked to the fourth carbon (C4) of the second glucose, indicated as (1→4).
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Two monosaccharides with equivalent molecular graphs (same chain length and same carbonyl position) may still be distinct stereoisomers, whose molecules differ in spatial orientation. This happens only if the molecule contains a stereogenic center, specifically a carbon atom that is chiral (connected to four distinct molecular sub-structures). Those four bonds can have any of two configurations in space distinguished by their handedness. In a simple open- chain monosaccharide, every carbon is chiral except the first and the last atoms of the chain, and (in ketoses) the carbon with the keto group.
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Glucal in its preferred half- chair conformation Glycals can be formed as pyranose (six-membered) or furanose (five-membered) rings, depending on the monosaccharide used as a starting material to synthesize the glycal. Glycals can also be classified as endo-glycals or exo-glycals. A glycal is an endo-glycal when the double bond is within the ring. If the hydroxyl group on carbon 1 has been replaced with another carbon atom, a double bond can also form outside the ring between carbon 1 and this new carbon.
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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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Furthermore, EPA and DHA inhibit key regulators of the inflammatory process and suppress their activation which can help alleviate pain and reduce inflamed joints associated with many skeletal disorders. Ensuring an appropriate ratio of omega-3 to omega-6 fatty acids of approximately 5:1 is very important for inflammation processes. Animals source, specifically marine life such as fish, krill, and mussels, and plant sources such as flaxseed, soybean and canola oil, are particularly rich in omega-3 fatty acids. Glucosamine is an amino-monosaccharide that naturally occurs in all tissues, particularly in articular cartilage of joints and from the biosynthesis of glucose.
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Before monosaccharide units are incorporated into glycoproteins, polysaccharides, or lipids in living organisms, they are typically first "activated" by being joined via a glycosidic bond to the phosphate group of a nucleotide such as uridine diphosphate (UDP), guanosine diphosphate (GDP), thymidine diphosphate (TDP), or cytidine monophosphate (CMP). These activated biochemical intermediates are known as sugar nucleotides or sugar donors. Many biosynthetic pathways use mono- or oligosaccharides activated by a diphosphate linkage to lipids, such as dolichol. These activated donors are then substrates for enzymes known as glycosyltransferases, which transfer the sugar unit from the activated donor to an accepting nucleophile (the acceptor substrate).
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Open-chain monosaccharides with same molecular graph may exist as two or more stereoisomers. The Fischer projection is a systematic way of drawing the skeletal formula of an open-chain monosaccharide so that each stereoisomer is uniquely identified. Two isomers whose molecules are mirror-images of each other are identified by prefixes '-' or '-', according to the handedness of the chiral carbon atom that is farthest from the carbonyl. In the Fischer projection, that is the second carbon from the bottom; the prefix is '-' or '-' according to whether the hydroxyl on that carbon lies to the right or left of the backbone, respectively.
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Fructose, or fruit sugar, is a simple ketonic monosaccharide found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed directly into blood during digestion. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847.Dubrunfaut (1847) "Sur une propriété analytique des fermentations alcoolique et lactique, et sur leur application à l’étude des sucres" (On an analytic property of alcoholic and lactic fermentations, and on their application to the study of sugars), Annales de Chimie et de Physique, 21 : 169–178.
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Figure 4: Hydrolysis of sucrose to glucose and fructose by sucrase Figure 5: Intestinal sugar transport proteins Fructose exists in foods either as a monosaccharide (free fructose) or as a unit of a disaccharide (sucrose). Free fructose is absorbed directly by the intestine. When fructose is consumed in the form of sucrose, it is digested (broken down) and then absorbed as free fructose. As sucrose comes into contact with the membrane of the small intestine, the enzyme sucrase catalyzes the cleavage of sucrose to yield one glucose unit and one fructose unit, which are then each absorbed.
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The company's focus is to provide products, services for characterisation and quality control of biopharmaceutical glycosylation. Current products include kits and reagents for detailed analysis of N-linked and O-linked glycans by HPLC and mass spectrometry. Current services include contract glycosylation analysis to support biopharmaceutical development and regulatory submissions to the US Food and Drug Administration and European Medicines Agency, glycoprofiling method development, and training in biopharmaceutical glycoprofiling procedures. The key glycoprofiling modules include monosaccharide analysis, sialic acid analysis to determine relative levels of human vs non-human sialylation, oligosaccharide profiling, and detailed glycan structure analysis.
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Galactosidases are enzymes (glycoside hydrolases) that catalyze the hydrolysis of galactosides into monosaccharides. Galactosides can be classified as either alpha or beta. If the galactoside is classified as an alpha-galactoside, the enzyme is called alpha-galactosidase, and is responsible for catalyzing the hydrolysis of substrates that contain α-galactosidic residues, such as glycosphingolipids or glycoproteins. On the other hand, if it is a beta- galactoside, it is called beta-galactosidase, and is responsible for breaking down the disaccharide lactose into its monosaccharide components, glucose and galactose Both varieties of galactosidase are categorized under the EC number 3.2.1.
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The digestion of many polysaccharides and glycoproteins yields mannose, which is phosphorylated by hexokinase to generate mannose-6-phosphate. Mannose-6-phosphate is converted to fructose-6-phosphate, by the enzyme phosphomannose isomerase, and then enters the glycolytic pathway or is converted to glucose-6-phosphate by the gluconeogenic pathway of hepatocytes. Mannose is a dominant monosaccharide in N-linked glycosylation, which is a post-translational modification of proteins. It is initiated by the en bloc transfer on Glc3Man9GlcNAc2 to nascent glycoproteins in the endoplasmic reticulum in a co-translational manner as the protein entered through the transport system.
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Simple monosaccharides have a linear and unbranched carbon skeleton with one carbonyl (C=O) functional group, and one hydroxyl (OH) group on each of the remaining carbon atoms. Therefore, the molecular structure of a simple monosaccharide can be written as H(CHOH)n(C=O)(CHOH)mH, where n + 1 + m = x; so that its elemental formula is CxH2xOx. By convention, the carbon atoms are numbered from 1 to x along the backbone, starting from the end that is closest to the C=O group. Monosaccharides are the simplest units of carbohydrates and the simplest form of sugar.
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Fermentable carbohydrates are generally 3-10 monosaccharide units joined by glycosidic bonds which cannot be degraded by endogenous enzymes and require the fermentation processes of intestinal microflora for proper degradation. Non-fermentable fibres are carbohydrate structures which are not fully fermented even by intestinal microflora. Little research has been done on non-fermentable fibre, however it is known that it causes fecal bulking and reduced intestinal transit time. It has been shown that addition of non-fermentable fibre in concentrations of 22% or greater of the total diet will reduce growth, feed intake and feed efficiency.
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Sedoheptulose or D-altro-heptulose is a ketoheptose--a monosaccharide with seven carbon atoms and a ketone functional group. It is one of the few heptoses found in nature, and is found in various fruits and vegetables ranging from carrots and leeks to figs, mangos and avocados. It is an intermediate in respiratory and photosynthetic pathways and plays a vital role in the non-oxidative branch of the pentose phosphate pathway. Studies have shown that sedoheptulose is able to reduce pro-inflammatory markers in vitro such as interleukin-6 (IL-6) and C-reactive protein and thus might be able reduce low-level inflammation in humans.
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1,5-Anhydroglucitol, also known as 1,5-AG, is a naturally occurring monosaccharide found in nearly all foods. Blood concentrations of 1,5-anhydroglucitol decrease during times of hyperglycemia above 180 mg/dL, and return to normal levels after approximately 2 weeks in the absence of hyperglycemia. As a result, it can be used for people with either type-1 or type-2 diabetes mellitus to identify glycemic variability or a history of high blood glucose even if current glycemic measurements such as hemoglobin A1c (HbA1c) and blood glucose monitoring have near normal values. Despite this possible use and its approval by the FDA, 1,5-AG tests are rarely ordered.
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In the laboratory, her research focused on the biochemistry of the lens, in particular the biochemical pathways involved in the formation of cataracts. Pirie and van Heyningen co-authored Biochemistry of the Eye, published in 1956. Van Heyningen is credited with discovering novel pathways (such as the sorbitol pathway) involved in cataract formation, as well as pioneering novel techniques to identify relevant compounds and their interactions. For example, by examining the lenses of diabetic and non-diabetic patients (collected post- surgery or post-portem), she demonstrated that monosaccharide sugars accumulate in the lenses of diabetic patients, generating sugar alcohols that are harmful to the lens.
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Monosaccharides with three carbon atoms are called trioses, those with four are called tetroses, five are called pentoses, six are hexoses, and so on. These two systems of classification are often combined. For example, glucose is an aldohexose (a six-carbon aldehyde), ribose is an aldopentose (a five-carbon aldehyde), and fructose is a ketohexose (a six-carbon ketone). Each carbon atom bearing a hydroxyl group (-OH), with the exception of the first and last carbons, are asymmetric, making them stereo centers with two possible configurations each (R or S). Because of this asymmetry, a number of isomers may exist for any given monosaccharide formula.
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In 1985 he was appointed the James B. Duke Professor of Chemistry. At Duke University, his research shifted to exploring the role of oligosaccharides in immune responses, and particularly on the effect of molecules on human diseases like malaria and AIDS. After retiring from Duke in 1996, due to an undisclosed harassment claim, he established the Natural Products & Glycotechnology Research Institute, a nonprofit, to study the carbohydrate chemistry/biology of tropical parasitic diseases in developing countries and to develop a carbohydrate-based malaria vaccine. Fraser-Reid and his team achieved a milestone in oligosaccharide synthesis by assembling a molecule consisting of 28 monosaccharide units.
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The essential feature of a glycolipid is the presence of a monosaccharide or oligosaccharide bound to a lipid moiety. The most common lipids in cellular membranes are glycerolipids and sphingolipids, which have glycerol or a sphingosine backbones, respectively. Fatty acids are connected to this backbone, so that the lipid as a whole has a polar head and a non-polar tail. The lipid bilayer of the cell membrane consists of two layers of lipids, with the inner and outer surfaces of the membrane made up of the polar head groups, and the inner part of the membrane made up of the non-polar fatty acid tails.
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A handful of malted barley, the white sprouts visible Beer malt varieties from Bamberg, Germany Malt is germinated cereal grain that has been dried in a process known as "malting". The grain is made to germinate by soaking in water and is then halted from germinating further by drying with hot air. Malting grain develops the enzymes (α-amylase, β-amylase) required for modifying the grains' starches into various types of sugar, including monosaccharide glucose, disaccharide maltose, trisaccharide maltotriose, and higher sugars called maltodextrines. It also develops other enzymes, such as proteases, that break down the proteins in the grain into forms that can be used by yeast.
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Threose is a four-carbon monosaccharide with molecular formula C4H8O4. It has a terminal aldehyde group rather than a ketone in its linear chain, and so is considered part of the aldose family of monosaccharides. The threose name can be used to refer to both the D\- and L-stereoisomers, and more generally to the racemic mixture (D/L-, equal parts D\- and L-) as well as to the more generic threose structure (absolute stereochemistry unspecified). The prefix "threo" which derives from threose (and "erythro" from a corresponding diastereomer erythrose) offer a useful way to describe general organic structures with adjacent chiral centers, where "the prefixes... designate the relative configuration of the centers".
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Glucose can exist in both a straight-chain and ring form. The aldehyde or ketone group of a straight-chain monosaccharide will react reversibly with a hydroxyl group on a different carbon atom to form a hemiacetal or hemiketal, forming a heterocyclic ring with an oxygen bridge between two carbon atoms. Rings with five and six atoms are called furanose and pyranose forms, respectively, and exist in equilibrium with the straight- chain form. During the conversion from straight-chain form to the cyclic form, the carbon atom containing the carbonyl oxygen, called the anomeric carbon, becomes a stereogenic center with two possible configurations: The oxygen atom may take a position either above or below the plane of the ring.
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An experiment published in the International Journal of Dairy Technology suggested that the level of galactose, a monosaccharide sugar that is less sweet than glucose and fructose, can be reduced using different culture techniques. An article in the International Journal of Food Engineering found that trisodium citrate, a food additive used to preserve and add flavor to foods, slightly improved the preferred qualities of pizza cheese. Research published in Dairy Industries International suggested that denatured whey proteins increased moisture retention, but that the improvements were very slight and not economically worthwhile relative to the minor improvements. Some consumers prefer pizza cheese with less browning, which can be achieved using low-moisture part-skim Mozzarella with a low galactose content.
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Plant-derived polyphenol, tannic acid, formed by esterification of ten equivalents of the phenylpropanoid-derived gallic acid to a monosaccharide (glucose) core from primary metabolism Phenol-phenolate equilibrium, and resonance structures giving rise to phenol aromatic reactivity Polyphenols (; also known as polyhydroxyphenols) are a structural class of mainly natural, but also synthetic or semisynthetic, organic chemicals characterized by the presence of large multiples of phenol structural units. The number and characteristics of these phenol structures underlie the unique physical, chemical, and biological (metabolic, toxic, therapeutic, etc.) properties of particular members of the class. Examples include tannic acid and ellagitannin. The historically important chemical class of tannins is a subset of the polyphenols.
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During this time Heidelberger was approached by the bacteriologist Oswald Avery to help him elucidate the chemistry of the "specific soluble substance" Avery and Alphonse R. Dochez had found in the spherical capsule that envelops pneumococcus and many other species of bacteria. In 1923, Heidelberger and Avery reported that this capsular substance, which determined the specific type of pneumococcus and, with it, its virulence, consisted of polysaccharides, carbohydrate molecules made up of more than three monosaccharide units. Their discovery for the first time established a relationship between chemical constitution and immunological specificity of antigens, thereby putting the field of immunology on a firm biochemical footing. It also disproved prevailing assumptions among scientists that only proteins could act as antigens.
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Two of the main functions of carbohydrates are energy storage and providing structure. One of the common sugars known as glucose is carbohydrate, but not all carbohydrates are sugars. There are more carbohydrates on Earth than any other known type of biomolecule; they are used to store energy and genetic information, as well as play important roles in cell to cell interactions and communications. The simplest type of carbohydrate is a monosaccharide, which among other properties contains carbon, hydrogen, and oxygen, mostly in a ratio of 1:2:1 (generalized formula CnH2nOn, where n is at least 3). Glucose (C6H12O6) is one of the most important carbohydrates; others include fructose (C6H12O6), the sugar commonly associated with the sweet taste of fruits,Whiting (1970), pp. 1–31.
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The formation of a disaccharide molecule from two monosaccharide molecules proceeds by displacing a hydroxyl radical from one molecule and a hydrogen nucleus (a proton) from the other, so that the now vacant bonds on the monosaccharides join the two monomers together. The vacant bonds on the hydroxyl radical and the proton unite in their turn, forming a molecule of water, that then goes free. Because of the removal of the water molecule from the product, the term of convenience for such a process is "dehydration reaction" (also "condensation reaction" or "dehydration synthesis"). For example, milk sugar (lactose) is a disaccharide made by condensation of one molecule of each of the monosaccharides glucose and galactose, whereas the disaccharide sucrose in sugar cane and sugar beet, is a condensation product of glucose and fructose.
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Part of the variability seen in saccharide structures is because monosaccharide units may be coupled to each other in many different ways, as opposed to the amino acids of proteins or the nucleotides in DNA, which are always coupled together in a standard fashion. The study of glycan structures is also complicated by the lack of a direct template for their biosynthesis, contrary to the case with proteins where their amino acid sequence is determined by their corresponding gene. Glycans are secondary gene products and therefore are generated by the coordinated action of many enzymes in the subcellular compartments of a cell. Since the structure of a glycan may depend on the expression, activity and accessibility of the different biosynthetic enzymes, it is not possible to use recombinant DNA technology in order to produce large quantities of glycans for structural and functional studies as it is for proteins.
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Carbohydrate conformation refers to the overall three-dimensional structure adopted by a carbohydrate (saccharide) molecule as a result of the through- bond and through-space physical forces it experiences arising from its molecular structure. The physical forces that dictate the three-dimensional shapes of all molecules—here, of all monosaccharide, oligosaccharide, and polysaccharide molecules—are sometimes summarily captured by such terms as "steric interactions" and "stereoelectronic effects" (see below). Saccharide and other chemical conformations can be reasonably shown using two-dimensional structure representations that follow set conventions; these capture for a trained viewer an understanding of the three-dimensional structure via structure drawings (see organic chemistry article, and "3D Representations" section in molecular geometry article); they are also represented by stereograms on the two dimensional page, and increasingly using 3D display technologies on computer monitors. Formally and quantitatively, conformation is captured by description of a molecule's angles—for example, sets of three sequential atoms (bond angles) and four sequential atoms (torsion angles, dihedral angles), where the locations and angular directions of nonbonding electrons ("lone pair electrons") must sometimes also be taken into account.
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