Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

X-ray Crystallography Reveals a Reduced Substrate Complex of UDP-Galactopyranose Mutase Poised for Covalent Catalysis by Flavin

Journal Article · · Biochemistry-US
DOI:https://doi.org/10.1021/bi901437v· OSTI ID:1005941
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 {angstrom} 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 {angstrom} from the nucleophilic flavin N5 position. This orientation is consistent with covalent catalysis by flavin.
Research Organization:
Argonne National Laboratory (ANL)
Sponsoring Organization:
USDOE
OSTI ID:
1005941
Journal Information:
Biochemistry-US, Journal Name: Biochemistry-US Journal Issue: (39) ; 10, 2009 Vol. 48; ISSN 0006-2960; ISSN BICHAW
Country of Publication:
United States
Language:
ENGLISH

Similar Records

Ligand Binding and Substrate Discrimination by UDP-Galactopyranose Mutase
Journal Article · Fri Jul 31 00:00:00 EDT 2009 · J. Mol. Biol. · OSTI ID:1005764

Conformational Control of UDP-Galactopyranose Mutase Inhibition
Journal Article · Mon Jun 12 20:00:00 EDT 2017 · Biochemistry · OSTI ID:1374629

Crystal Structures and Small-angle X-ray Scattering Analysis of UDP-galactopyranose Mutase from the Pathogenic Fungus Aspergillus fumigatus
Journal Article · Thu Oct 15 00:00:00 EDT 2015 · Journal of Biological Chemistry · OSTI ID:1037486