Structural highlights
Function
[GLF1_KLEPN] Involved in the biosynthesis of the galactose-containing O-side-chain polysaccharide backbone structure of D-galactan I which is a key component of lipopolysaccharide (LPS). Catalyzes the interconversion through a 2-keto intermediate of uridine diphosphogalactopyranose (UDP-GalP) into uridine diphosphogalactofuranose (UDP-GalF) which is the biosynthetic precursor of galactofuranosyl residues.[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The flavoenzyme uridine 5'-diphosphate galactopyranose mutase (UGM or Glf) catalyzes the interconversion of UDP-galactopyranose and UDP-galactofuranose. The latter is a key building block for cell wall construction in numerous pathogens, including Mycobacterium tuberculosis. Mechanistic studies of UGM suggested a novel role for the flavin, and we previously provided evidence that the catalytic mechanism proceeds through a covalent flavin-galactose iminium. Here, we describe 2.3 and 2.5 A resolution X-ray crystal structures of the substrate-bound enzyme in oxidized and reduced forms, respectively. In the latter, C1 of the substrate is 3.6 A from the nucleophilic flavin N5 position. This orientation is consistent with covalent catalysis by flavin.
X-ray Crystallography Reveals a Reduced Substrate Complex of UDP-Galactopyranose Mutase Poised for Covalent Catalysis by Flavin .,Gruber TD, Westler WM, Kiessling LL, Forest KT Biochemistry. 2009 Sep 10. PMID:19719175[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Koplin R, Brisson JR, Whitfield C. UDP-galactofuranose precursor required for formation of the lipopolysaccharide O antigen of Klebsiella pneumoniae serotype O1 is synthesized by the product of the rfbDKPO1 gene. J Biol Chem. 1997 Feb 14;272(7):4121-8. PMID:9020123
- ↑ Gruber TD, Westler WM, Kiessling LL, Forest KT. X-ray Crystallography Reveals a Reduced Substrate Complex of UDP-Galactopyranose Mutase Poised for Covalent Catalysis by Flavin . Biochemistry. 2009 Sep 10. PMID:19719175 doi:10.1021/bi901437v
