JV-Acetylglucosamine

Hexoses glucose, fructose, mannose, sorbose, trehalose, galactose, JV-acetylglucosamine, j3-glucoside... 

Enzyme preparations pretreated by dialysis at pH 9.2 (dialysis) or with digitonin (digitonin), or UDP-JV-acetylglucosamine (UDPNAGA) added to enzymatic incubation mixtures. 

Duverger, E., Roche, A.C. and Monsigny, M. (1996) jV-acetylglucosamine-dependent nuclear import of neoglycoproteins. Glycobiology, 6, 381-386. 

Acetylmannosamine 6.25 can be prepared by epimerization of JV-acetylglucosamine (1.7) in aqueous solution at pH 11. After 3 days at room temperature the yield is 22%, but the starting material is very accessible. 

Keratosulphate Keratan sulphate JV-acetylglucosamine-6-sulphate galactose Bone, cornea, nucleus polposus... 

Carbohydrates are linked to some soluble proteins as well as membrane proteins. In particular, many of the proteins secreted from cells are glycosylated. Most proteins present in the serum component of blood are glycoproteins (Figure 11.20). Furthermore, JV-acetylglucosamine residues are 0-linked to some intracellular proteins. The role of these carbohydrates, which are dynamically added and removed, is under active investigation. 

S. Bonnin, F. Besson, M. Gelhausen, S. Chierici, and B. Roux, A FTIR spectroscopy evidence of the interactions between wheat germ agglutinin and JV-acetylglucosamine residues, FEBS Lett., 456 (1999) 361-364. 

The cell wall is composed mainly of a polymer of jV-acetylglucosamine known as chitin, although there may also be limited amounts of cellulose present. 

Kobyashi S., Makino A., Matsumoto H., Kunii S., Ohmae M., Kiyosada T., Makiguchi K., Matsumoto A., Horie M., Shoda S.I., Enzymatic polymerization to novel polysaccharides having a glucose-JV-acetylglucosamine repeating unit, a ceUulose-chitin hybrid polysaccharide. Biomacromolecules, 7, 2006,1644-1656. 

Kobyashi S., Makino A., Tachibana N., Ohmae M., Chitinase-catalyzed synthesis of a chitin-xylan hybrid polymer A novel water-soluble P(1 <— 4) polysaccharide having an JV-acetylglucosamine-xylose repeating unit, Macromol. Rapid Comm., 27,2006, 781-786. 

A mucopolysaccharide composed of JV-Acetylglucosamine and D-Glucuro-nic acid. MW= 1 -8 x 10. Polymeric. Minimum formula given. Found in the extracellular matrix of all higher animals, esp. in soft connective tissues. Isol. from synovial fluid, amniotic fluid, etc. Functions as a joint lubricant and shock absorber used in the treatment of synovitis and osteoarthritis. Approved for clinical use in the EU (1999)Md -68.2 (c, l.O in H2O). 

Figure 10.345 shows the analysis of monosaccharides of a membrane-immobilized mAb, which predominantly contains fiicose, JV-acetylglucosamine, galactose, and mannose. The monosaccharide ratios in IgG monoclonal antibodies are summarized in Table 10.36 the different signals in amperometric detection... 

JV-acetylglucosamine-e-phosphate — JV-acetylglucosamine-l-phosphate IV-acetylglucosamine-l-pliosphate + UTP — UDPAG + PP... 

The sequence of reactions by which the amino sugar is incorporated into polysaccharides is not clear. It is not known whether a phosphorylated compound is essential to this synthesis. Hexokinase does not appear to phosphorylate JV-acetylglucosamine. In studies on the biosynthesis of hyaluronic acid by Streptococcus hemolyticus, glucose-l-C was added to the medium. Glucosamine was isolated from the synthesized polysaccharide, and the major fraction of the radioactivity of the compound was present in Ci. This experiment suggests that the glucosamine moiety of hyaluronic acid arises from glucose. ... 

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