3C4V

Structure of the retaining glycosyltransferase MshA:The first step in mycothiol biosynthesis. Organism: Corynebacterium glutamicum : Complex with UDP and 1L-INS-1-P.

Summary for 3C4V

• Entry DOI: 10.2210/pdb3c4v/pdb
• Related: 3C48 3C4Q
• Descriptor: Predicted glycosyltransferases, MAGNESIUM ION, URIDINE-5'-DIPHOSPHATE, ... (5 entities in total)
• Functional Keywords: retaining glycosyltransferase, beta alpha beta, substrate assisted catalysis, transferase
• Biological source: Corynebacterium glutamicum
• Total number of polymer chains: 2
• Total formula weight: 94699.80

Authors

Vetting, M.W.,Frantom, P.A.,Blanchard, J.S. (deposition date: 2008-01-30, release date: 2008-04-01, Last modification date: 2023-08-30)

Primary citation

Vetting, M.W.,Frantom, P.A.,Blanchard, J.S.
Structural and Enzymatic Analysis of MshA from Corynebacterium glutamicum: SUBSTRATE-ASSISTED CATALYSIS
J.Biol.Chem., 283:15834-15844, 2008

PubMed Abstract: The glycosyltransferase termed MshA catalyzes the transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to 1-L-myo-inositol-1-phosphate in the first committed step of mycothiol biosynthesis. The structure of MshA from Corynebacterium glutamicum was determined both in the absence of substrates and in a complex with UDP and 1-L-myo-inositol-1-phosphate. MshA belongs to the GT-B structural family whose members have a two-domain structure with both domains exhibiting a Rossman-type fold. Binding of the donor sugar to the C-terminal domain produces a 97 degrees rotational reorientation of the N-terminal domain relative to the C-terminal domain, clamping down on UDP and generating the binding site for 1-L-myo-inositol-1-phosphate. The structure highlights the residues important in binding of UDP-N-acetylglucosamine and 1-L-myo-inositol-1-phosphate. Molecular models of the ternary complex suggest a mechanism in which the beta-phosphate of the substrate, UDP-N-acetylglucosamine, promotes the nucleophilic attack of the 3-hydroxyl group of 1-L-myo-inositol-1-phosphate while at the same time promoting the cleavage of the sugar nucleotide bond.

PubMed: 18390549
DOI: 10.1074/jbc.M801017200

Experimental method

X-RAY DIFFRACTION (2.6 Å)