1nvk
T4 phage BGT in complex with UDP and a Mn2+ ion at 1.8 A resolution
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OverviewOverview
T4 phage beta-glucosyltransferase (BGT) is an inverting, glycosyltransferase (GT) that transfers glucose from uridine, diphospho-glucose (UDP-glucose) to an acceptor modified DNA. BGT belongs, to the GT-B structural superfamily, represented, so far, by five different, inverting or retaining GT families. Here, we report three high-resolution, X-ray structures of BGT and a point mutant solved in the presence of, UDP-glucose. The two co-crystal structures of the D100A mutant show that, unlike the wild-type enzyme, this mutation prevents glucose hydrolysis., This strongly indicates that Asp100 is the catalytic base. We obtained the, wild-type BGT-UDP-glucose complex by soaking substrate-free BGT crystals., Comparison with a previous structure of BGT solved in the presence of the, donor product UDP and an acceptor analogue provides the first model of an, inverting GT-B enzyme in which both the donor and acceptor substrates are, bound to the active site. The structural analyses support the in-line, displacement reaction mechanism previously proposed, locate residues, involved in donor substrate specificity and identify the catalytic base.
About this StructureAbout this Structure
1NVK is a Single protein structure of sequence from Bacteriophage t4 with MN, UDP and GOL as ligands. Active as DNA beta-glucosyltransferase, with EC number 2.4.1.27 Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of the T4 phage beta-glucosyltransferase and the D100A mutant in complex with UDP-glucose: glucose binding and identification of the catalytic base for a direct displacement mechanism., Lariviere L, Gueguen-Chaignon V, Morera S, J Mol Biol. 2003 Jul 25;330(5):1077-86. PMID:12860129
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