UDP-N-acetylglucosamine 2-epimerase explained

UDP-N-acetylglucosamine 2-epimerase
Ec Number:	5.1.3.14
Cas Number:	9037-71-2
Go Code:	0008761

Symbol:	Epimerase_2
UDP-N-acetylglucosamine 2-epimerase
Pfam:	PF02350
Pfam Clan:	CL0113
Interpro:	IPR003331
Scop:	1f6d
Cdd:	cd03786

In enzymology, an UDP-N-acetylglucosamine 2-epimerase is an enzyme that catalyzes the chemical reaction

UDP-N-acetyl-D-glucosamine

\rightleftharpoons UDP-N-acetyl-D-mannosamine

Hence, this enzyme has one substrate, UDP-N-acetyl-D-glucosamine, and one product, UDP-N-acetyl-D-mannosamine.

This enzyme belongs to the family of isomerases, specifically those racemases and epimerases acting on carbohydrates and derivatives. The systematic name of this enzyme class is UDP-N-acetyl-D-glucosamine 2-epimerase. Other names in common use include UDP-N-acetylglucosamine 2'-epimerase, uridine diphosphoacetylglucosamine 2'-epimerase, uridine diphospho-N-acetylglucosamine 2'-epimerase, and uridine diphosphate-N-acetylglucosamine-2'-epimerase. This enzyme participates in aminosugars metabolism.

In microorganisms this epimerase is involved in the synthesis of the capsule precursor UDP-ManNAcA.^{[1] [2]} An inhibitor of the bacterial 2-epimerase, epimerox, has been described. Some of these enzymes are bifunctional. The UDP-N-acetylglucosamine 2-epimerase from rat liver displays both epimerase and kinase activity.^[3]

Structural studies

As of late 2007, 4 structures have been solved for this class of enzymes, with PDB accession codes,,, and .

See also

• UDP-N-acetylglucosamine 2-epimerase (hydrolysing)

Further reading

• Kikuchi K, Tsuiki S . 1973 . Purification and properties of UDP-N-acetylglucosamine 2'-epimerase from rat liver . Biochim. Biophys. Acta . 327 . 193 - 206 . 4770741 . 1 . 10.1016/0005-2744(73)90117-4.

Notes and References

1. Swartley JS, Liu LJ, Miller YK, Martin LE, Edupuganti S, Stephens DS . Characterization of the Gene Cassette Required for Biosynthesis of the (α1→6)-Linked N-Acetyl-d-Mannosamine-1-Phosphate Capsule of Serogroup A Neisseria meningitidis . J. Bacteriol. . 180 . 6 . 1533–9 . March 1998 . 9515923 . 107054 . 10.1128/JB.180.6.1533-1539.1998.
2. Kiser KB, Lee JC . Staphylococcus aureus cap5O and cap5P Genes Functionally Complement Mutations Affecting Enterobacterial Common-Antigen Biosynthesis in Escherichia coli . J. Bacteriol. . 180 . 2 . 403–6 . January 1998 . 9440531 . 106897 . 10.1128/JB.180.2.403-406.1998.
3. 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 . 39 . 24319–24 . September 1997 . 9305888 . 10.1074/jbc.272.39.24319. free .