UDP-N-acetylglucosamine 2-epimerase [Cell wall/membrane/envelope biogenesis].

UDP-N-acetylglucosamine 2-epimerase. This cytosolic enzyme converts UDP-N-acetyl-D-glucosamine to UDP-N-acetyl-D-mannosamine. In E. coli, this is the first step in the pathway of enterobacterial common antigen biosynthesis.Members of this orthology group have many gene symbols, often reflecting the overall activity of the pathway and/or operon that includes it. Symbols include epsC (exopolysaccharide C) in Burkholderia solanacerum, cap8P (type 8 capsule P) in Staphylococcus aureus, and nfrC in an older designation based on the effects of deletion on phage N4 adsorption. Epimerase activity was also demonstrated in a bifunctional rat enzyme, for which the N-terminal domain appears to be orthologous. The set of proteins found above the suggested cutoff includes E. coli WecB in one of two deeply branched clusters and the rat UDP-N-acetylglucosamine 2-epimerase domain in the other. [Cell envelope, Biosynthesis and degradation of surface polysaccharides and lipopolysaccharides]

UDP-N-acetylglucosamine 2-epimerase and similar proteins. Bacterial members of the UDP-N-Acetylglucosamine (GlcNAc) 2-Epimerase family (EC 5.1.3.14) are known to catalyze the reversible interconversion of UDP-GlcNAc and UDP-N-acetylmannosamine (UDP-ManNAc). The enzyme serves to produce an activated form of ManNAc residues (UDP-ManNAc) for use in the biosynthesis of a variety of cell surface polysaccharides; The mammalian enzyme is bifunctional, catalyzing both the inversion of stereochemistry at C-2 and the hydrolysis of the UDP-sugar linkage to generate free ManNAc. It also catalyzes the phosphorylation of ManNAc to generate ManNAc 6-phosphate, a precursor to salic acids. In mammals, sialic acids are found at the termini of oligosaccharides in a large variety of cell surface glycoconjugates and are key mediators of cell-cell recognition events. Mutations in human members of this family have been associated with Sialuria, a rare disease caused by the disorders of sialic acid metabolism. This family belongs to the GT-B structural superfamily of glycoslytransferases, which have characteristic N- and C-terminal domains each containing a typical Rossmann fold. The two domains have high structural homology despite minimal sequence homology. The large cleft that separates the two domains includes the catalytic center and permits a high degree of flexibility.

UDP-N-acetylglucosamine 2-epimerase. This family consists of UDP-N-acetylglucosamine 2-epimerases EC:5.1.3.14 this enzyme catalyzes the production of UDP-ManNAc from UDP-GlcNAc. Note that some of the enzymes is this family are bifunctional, in these instances Pfam matches only the N-terminal half of the protein suggesting that the additional C-terminal part (when compared to mono-functional members of this family) is responsible for the UPD-N-acetylmannosamine kinase activity of these enzymes. This hypothesis is further supported by the assumption that the C-terminal part of rat Gne is the kinase domain.

Escherichia coli alpha-1,3-mannosyltransferase WfcD and similar proteins. This family is most closely related to the GT4 family of glycosyltransferases. Glycosyltransferases catalyze the transfer of sugar moieties from activated donor molecules to specific acceptor molecules, forming glycosidic bonds. The acceptor molecule can be a lipid, a protein, a heterocyclic compound, or another carbohydrate residue. This group of glycosyltransferases is most closely related to the previously defined glycosyltransferase family 1 (GT1). The members of this family may transfer UDP, ADP, GDP, or CMP-linked sugars. The diverse enzymatic activities among members of this family reflect a wide range of biological functions. The protein structure available for this family has the GTB topology, one of the two protein topologies observed for nucleotide-sugar-dependent glycosyltransferases. GTB proteins have distinct N- and C- terminal domains each containing a typical Rossmann fold. The two domains have high structural homology despite minimal sequence homology. The large cleft that separates the two domains includes the catalytic center and permits a high degree of flexibility. The members of this family are found mainly in bacteria and eukaryotes.

Crystalstructure of Bacillus subtilis UDP-GlcNAc 2-epimerase in complex with UDP-GlcNAc and UDP [Bacillus subtilis subsp. subtilis str. 168],4FKZ_B Crystal structure of Bacillus subtilis UDP-GlcNAc 2-epimerase in complex with UDP-GlcNAc and UDP [Bacillus subtilis subsp. subtilis str. 168]

AStructural Basis for the allosteric regulation of non-hydrolyzing UDP-GlcNAc 2-epimerases [Bacillus anthracis],3BEO_B A Structural Basis for the allosteric regulation of non-hydrolyzing UDP-GlcNAc 2-epimerases [Bacillus anthracis]

2.2Angstrom Resolution Crystal Structure of putative UDP-N-acetylglucosamine 2-epimerase from Listeria monocytogenes [Listeria monocytogenes EGD-e],3OT5_B 2.2 Angstrom Resolution Crystal Structure of putative UDP-N-acetylglucosamine 2-epimerase from Listeria monocytogenes [Listeria monocytogenes EGD-e],3OT5_C 2.2 Angstrom Resolution Crystal Structure of putative UDP-N-acetylglucosamine 2-epimerase from Listeria monocytogenes [Listeria monocytogenes EGD-e],3OT5_D 2.2 Angstrom Resolution Crystal Structure of putative UDP-N-acetylglucosamine 2-epimerase from Listeria monocytogenes [Listeria monocytogenes EGD-e]

Crystalstructure of UDP-N-acetylglucosamine 2-epimerase [Bacillus subtilis],1O6C_B Crystal structure of UDP-N-acetylglucosamine 2-epimerase [Bacillus subtilis]

S.aureus MnaA-UDP co-structure [Staphylococcus aureus],5ENZ_B S. aureus MnaA-UDP co-structure [Staphylococcus aureus]

UDP-N-acetylglucosamine 2-epimerase OS=Bacillus subtilis (strain 168) OX=224308 GN=mnaA PE=1 SV=1

Putative UDP-N-acetylglucosamine 2-epimerase OS=Clostridium acetobutylicum (strain ATCC 824 / DSM 792 / JCM 1419 / LMG 5710 / VKM B-1787) OX=272562 GN=CA_C2874 PE=3 SV=2

Putative UDP-N-acetylglucosamine 2-epimerase OS=Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8) OX=243274 GN=TM_1034 PE=3 SV=1

Probable UDP-N-acetylglucosamine 2-epimerase OS=Ralstonia solanacearum OX=305 GN=epsC PE=3 SV=2

UDP-N-acetylglucosamine 2-epimerase OS=Yersinia pestis OX=632 GN=wecB PE=3 SV=1