A-acetyl-D-glucosamine

The anion of nitromethane adds easily to the carbonyl functions of sugars. This is a useful strategy for extension of the carbon chain.100 2-Acetamido-2-deoxy-P-D-glucose (A-acetyl-D-glucosamine) is the carbohydrate unit of glycoproteins that occurs most often. The nitromethy-lation method provides a straightforward route to a series of C-glycosyl compounds with the acetamido functionality (Eq. 3.62).101... 

We propose that the first step in NDP-kasugamine biosynthesis is 2-epimeriza-tion of the postulated UDP-A -acetyl-D-glucosamine precursor, which is suggested by the similarity of the KasQ protein with known UDP-(Af-acetyl-)D-glucosamine 2-epimerases and catalyzes the conversion to UDP-N-acetyl-D-mannosamine. To... 

This enzyme [EC 3.2.1.14] (also referred to as chitodex-trinase, l,4-j8-poly-A-acetylglucosaminidase, and poly-j8-glucosaminidase) catalyzes the hydrolysis of the l,4-j8-linkages of A-acetyl-D-glucosamine polymers of chitin. It should be noted that some chitinases will also display the activity observed with lysozyme [EC 3.2.1.17]. 

This enzyme [EC 3.5.1.41] catalyzes the hydrolysis of chitin (or, more specifically, the A-acetamido groups of A-acetyl-D-glucosamine residues in chitin) to produce chitosan and acetate. 

This enzyme [EC 2.4.1.16], also known as chitin-UDP N-acetylglucosaminyltransferase, catalyzes the reaction of UDP-A-acetyl-D-glucosamine with [(1,4)-(A-ace tyl-jS-D-glucosaminyl)] to produce UDP and [(l,4)-(A-acetyl-j8-D-glucosaminyl)]( +i). The enzyme ultimately converts UDP-A-acetyl-D-glucosamine into chitin and UDP. 

HA is synthesized by hyaluronan synthase (systematic name alternating UDP-a-A-acetyl-D-glucosamine p-D-glucuronosyl-(l—5-3)-[nascent hyaluronan]... 

Bidochka, M. J., and Kachatourians, G. G. (1988b). A-acetyl-D-glucosamine-mediated regulation of extracellular protease in the entomopathogenic fungus Beauveria bassiana. Applied and Environmental Microbiology, 54, 2699-2704. 

The reaction time of a transglycosylation may also be an important determinant of the product outcome. For example, the (1-4) linked disaccharide (A A -diacetylchitobiose) was the initial product formed when a mixture of A-acetyl-D-glucosamine and p-nitrophenyl (3-d-2-A-acetyl glucosamide was treated with p-galactosidase from Aspergillus oryzae (Scheme 4.26).76 The only other transfer product observed was the corresponding (1-6) linked disaccharide formed at 10% of the total... 

A-Acetyl-d-glucosamine was treated with 4-penten-l-ol in the presence of 10-camphorsulfonic acid as catalyst. This provided an a- and p-anomeric mixture of the corresponding C4-spacer arm containing the glycomonomer. The a- and p-anomers were separated by column chromatography with CHCI3 and methyl alcohol and were isolated in 31% and 11% yields, respectively. 

Riemann, L., and Azam, F. (2002). Widespread A/-acetyl-D-glucosamine uptake among pelagic marine bacteria and its ecological implications. Applied and Environmental Microbiology 68, 5554-5562. 

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