Hydrolases;
Glycosylases;
Glycosidases, i.e. enzymes that hydrolyse O- and S-glycosyl compounds
BRITE hierarchy

UDP-N-acetyl-alpha-D-glucosamine hydrolase (2-epimerising)

UDP-N-acetyl-alpha-D-glucosamine + H2O = N-acetyl-D-mannosamine + UDP [RN:R00414]

R00414
Reaction

UDP-N-acetyl-alpha-D-glucosamine [CPD:C00043];
H2O [CPD:C00001]

The enzyme is found in mammalian liver, as well as in some pathogenic bacteria including Neisseria meningitidis and Staphylococcus aureus. It catalyses the first step of sialic acid (N-acetylneuraminic acid) biosynthesis. The initial product formed is the alpha anomer, which rapidly mutarotates to a mixture of anomers [2]. The mammalian enzyme is bifunctional and also catalyses EC 2.7.1.60, N-acetylmannosamine kinase.
cf. EC 5.1.3.14, UDP-N-acetylglucosamine 2-epimerase (non-hydrolysing).

EC 3.2.1.183 created 2012

1  [PMID:9305888]

Stasche R, Hinderlich S, Weise C, Effertz K, Lucka L, Moormann P, Reutter W

A bifunctional enzyme catalyzes the first two steps in N-acetylneuraminic acid biosynthesis of rat liver. Molecular cloning and functional expression of UDP-N-acetyl-glucosamine 2-epimerase/N-acetylmannosamine kinase.

J Biol Chem 272:24319-24 (1997)
DOI:10.1074/jbc.272.39.24319

[rno:114711]

2  [PMID:12603133]

Chou WK, Hinderlich S, Reutter W, Tanner ME

Sialic acid biosynthesis: stereochemistry and mechanism of the reaction catalyzed by the mammalian UDP-N-acetylglucosamine 2-epimerase.

J Am Chem Soc 125:2455-61 (2003)
DOI:10.1021/ja021309g

3  [PMID:15135418]

Blume A, Ghaderi D, Liebich V, Hinderlich S, Donner P, Reutter W, Lucka L

UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase, functionally expressed in and purified from Escherichia coli, yeast, and insect cells.

Protein Expr Purif 35:387-96 (2004)
DOI:10.1016/j.pep.2004.02.013

4  [PMID:15518580]

Murkin AS, Chou WK, Wakarchuk WW, Tanner ME

Identification and mechanism of a bacterial hydrolyzing UDP-N-acetylglucosamine 2-epimerase.

Biochemistry 43:14290-8 (2004)
DOI:10.1021/bi048606d

[nme:NMB0070]