Acetylglucosamine subunit

The rat liver a(2-3)SiaT (EMBL accession no. M97754) has been cloned and overexpressed in COS cells [102]. The enzyme transfers a sialic acid unit from CMP-sialic acid onto the 3-OH-group of a terminal -linked D-galactose in an a-mode. The galactose acceptor itself can be attached either to the 3-OH-group (type I) or the 4-OH-group (type II) of a N-acetylglucosamine subunit (Fig. 16). 

Figure 2.1 Chemical structure of the HA polysaccharide repeat unit showing some common modifications. Either the -COOH group of the glucuronic acid subunit or the -OH group of the acetylglucosamine subunit can be functionalised with reactive groups, Ri and Ri respectively, that allow crosslinking of the modified HA to form a hydrogel. Commonly used functional groups at each of these locations are shown in two columns below, (a) Esterified HA (benzyl ester) (b) HA-tyramide (c) thiol-modified HA (d) HA-hydrazide (e) HA-aldehyde (f) glycidyl methacrylate-modified HA and (g) methacrylated HA...

SuMEGi, M., Hunyadi-Gulyas, E., Medziheadszky, K. F., and Udvaedy, A. 26S proteasome subunits are O-linked N-acetylglucosamine-modified in Drosophila melanogaster. Biochem Biophys Res Commun 2003, 312, 1284-9. 

This enzyme [EC 3.1.6.14] catalyzes the hydrolysis of the 6-sulfate moieties of the A-acetylglucosamine 6-sulfate subunits of heparan sulfate and keratan sulfate. It has been suggested that this enzyme might be identical to A-sulfoglucosamine-6-sulfatase. 

Vancomycin acts by inhibiting the correct synthesis of cell walls in gram-positive bacteria by specifically inhibiting the incorporation of V-acetylmuramic acid (NAM) and A-acetylglucosamine (NAG), two important peptide subunits that are present in the peptidoglycan layer of these types of bacteria. 

Glycosaminoglycans. Long, unbranched polysaccharide chains composed of repeating disaccharide subunits in which one of the two sugars is either /V-acetylglucosamine or /V-acetylgalac-tosamine. 

The cross-linking (transpeptidation) of the peptidoglycan chains is facilitated by transpeptidases known as penicillin-binding proteins. 3-lactam antibiotics are analognes of D-alanyl-D-alanine, the terminal amino acid residnes on the precursor N-acetyhnuramic/N-acetylglucosamine (NAM/NAG)-peptide subunits of the nascent peptidoglycan layer. The structural similarity between /3-lactam antibiotics and D-alanyl-D-alanine facilitates their... 

Bao M, Elmendorf BJ, Booth JL, Drake RR, Canfield WM. Bovine UDP-A-acetylglucosamine lysosomal-enzyme A-acetyl-glucosamine-1-phosphotransferase. 11. Enzymatic characteriza-hon and identification of the catalytic subunit. J. Biol. Chem. 1996 271(49) 31446-31451. 

Several classes of non-polar binding sites also are present on the Con A molecule. Two of these, a site adjacent to the carbohydrate-specific site that interacts with phenyl P-glycosides of mannose, glucose and iV-acetylglucosamine [84], and 4 low affinity sites (one per subunit) that bind various non-polar molecules such as tryptophan and indoleacetic acid [85], are of special interest. 

Algl3, the sugar donor subunit of a yeast N-acetylglucosamine transferase 202 117 362... 

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