Summary: UDP-N-acetylglucosamine 2-epimerase
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UDP-N-acetylglucosamine 2-epimerase Edit Wikipedia article
|PDB structures||RCSB PDB PDBe PDBsum|
|Gene Ontology||AmiGO / EGO|
crystal structure of udp-n-acetylglucosamine_2 epimerase
- UDP-N-acetyl-D-glucosamine 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. 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.
- Swartley JS, Liu LJ, Miller YK, Martin LE, Edupuganti S, Stephens DS (March 1998). "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. PMC . PMID 9515923.
- Kiser KB, Lee JC (January 1998). "Staphylococcus aureus cap5O and cap5P Genes Functionally Complement Mutations Affecting Enterobacterial Common-Antigen Biosynthesis in Escherichia coli". J. Bacteriol. 180 (2): 403–6. PMC . PMID 9440531.
- Stasche R, Hinderlich S, Weise C, Effertz K, Lucka L, Moormann P, Reutter W (September 1997). "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. doi:10.1074/jbc.272.39.24319. PMID 9305888.
- Kikuchi K, Tsuiki S (1973). "Purification and properties of UDP-N-acetylglucosamine 2'-epimerase from rat liver". Biochim. Biophys. Acta. 327 (1): 193–206. doi:10.1016/0005-2744(73)90117-4. PMID 4770741.
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UDP-N-acetylglucosamine 2-epimerase Provide feedback
This family consists of UDP-N-acetylglucosamine 2-epimerases EC:18.104.22.168 this enzyme catalyses the production of UDP-ManNAc from UDP-GlcNAc. Note that some of the enzymes is this family are bifunctional such as O35826 and Q9Z0P6 in this instance 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 O35826 is the kinase domain .
Swartley JS, Liu LJ, Miller YK, Martin LE, Edupuganti S, Stephens DS; , J Bacteriol. 1998;180:1533-1539.: Characterization of the gene cassette required for biosynthesis of the (alpha1-->6)-linked N-acetyl-D-mannosamine-1-phosphate capsule of serogroup A Neisseria meningitidis. PUBMED:9515923 EPMC:9515923
Kiser KB, Lee JC; , J Bacteriol 1998;180:403-406.: Staphylococcus aureus cap5O and cap5P genes functionally complement mutations affecting enterobacterial common-antigen biosynthesis in Escherichia coli. PUBMED:9440531 EPMC:9440531
Stasche R, Hinderlich S, Weise C, Effertz K, Lucka L, Moormann P, Reutter W; , J Biol Chem 1997;272:24319-24324.: 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. PUBMED:9305888 EPMC:9305888
Internal database links
|SCOOP:||Capsule_synth DUF354 Glyco_tran_28_C Glyco_trans_1_2 Glyco_trans_1_4 Glyco_trans_4_2 Glyco_trans_4_4 Glyco_transf_28 Glyco_transf_4 Glyco_transf_9 Glycos_transf_1 Glyphos_transf LpxB UDPGT|
|Similarity to PfamA using HHSearch:||Glycos_transf_1 PS_pyruv_trans Glyphos_transf Glyco_trans_4_4|
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR003331
This entry represents a domain found in the bacterial UDP-N-acetylglucosamine 2-epimerase WecB, which is involved in the enterobacterial common antigen biosynthesis [PUBMED:2166030]. It can also be found in the N-terminal region of the mammalian bifunctional protein GNE, which has both the UDP-N-acetylglucosamine 2-epimerase and the N-acetylmannosamine kinase functions. GNE catalyses the first two steps of sialic acid biosynthesis in the cytosol [PUBMED:11929971].
Proteins containing this domain also include UDP-N,N'-diacetylbacillosamine 2-epimerase, which is involved in biosynthesis of legionaminic acid (5,7-diamino-3,5,7,9-tetradeoxy-D-glycero-D-galacto-non-2-ulosonic acid)(Leg), a sialic acid-like derivative that is incorporated into virulence-associated cell surface glycoconjugates such as lipopolysaccharide (LPS) which could be a key determinant in the ability of L. pneumophila to inhibit the fusion of phagosomes with lysosomes [PUBMED:18275154].
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
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This is the GT-B clan that contains diverse glycosyltransferases that possess a Rossmann like fold .
The clan contains the following 45 members:AGT ALG11_N Alg14 Asp1 Capsule_synth DUF1205 DUF1972 DUF3492 DUF354 Epimerase_2 Glyco_tran_28_C Glyco_trans_1_2 Glyco_trans_1_3 Glyco_trans_1_4 Glyco_trans_4_2 Glyco_trans_4_3 Glyco_trans_4_4 Glyco_trans_4_5 Glyco_transf_10 Glyco_transf_20 Glyco_transf_28 Glyco_transf_4 Glyco_transf_41 Glyco_transf_5 Glyco_transf_52 Glyco_transf_56 Glyco_transf_9 Glyco_transf_90 Glycogen_syn Glycos_transf_1 Glycos_transf_N Glyphos_transf LpxB MGDG_synth Mito_fiss_Elm1 NodZ O-FucT Phosphorylase PIGA PM0188 PS_pyruv_trans SUA5 Sucrose_synth T4-Gluco-transf UDPGT
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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|Seed source:||Pfam-B_888 (release 5.2) & Pfam-B_4862 (Release 7.5)|
|Author:||Bashton M, Bateman A|
|Number in seed:||94|
|Number in full:||3831|
|Average length of the domain:||329.10 aa|
|Average identity of full alignment:||30 %|
|Average coverage of the sequence by the domain:||86.98 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 26740544 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||18|
|Download:||download the raw HMM for this family|
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There is 1 interaction for this family. More...
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Epimerase_2 domain has been found. There are 32 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.
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