2c27

File:2c27.gif

spinqualitylabelsall models 2c27, resolution 1.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

THE STRUCTURE OF MYCOTHIOL SYNTHASE IN COMPLEX WITH DES-ACETYLMYCOTHIOL AND COENZYMEA.

OverviewOverview

The structure of the ternary complex of mycothiol synthase from, Mycobacterium tuberculosis with bound desacetylmycothiol and CoA was, determined to 1.8 A resolution. The structure of the acetyl-CoA-binary, complex had shown an active site groove that was several times larger than, its substrate. The structure of the ternary complex reveals that mycothiol, synthase undergoes a large conformational change in which the two, acetyltransferase domains are brought together through shared interactions, with the functional groups of desacetylmycothiol, thereby decreasing the, size of this large central groove. A comparison of the binary and ternary, structures illustrates many of the features that promote catalysis., Desacetylmycothiol is positioned with its primary amine in close proximity, and in the proper orientation for direct nucleophilic attack on the, si-face of the acetyl group of acetyl-CoA. Glu-234 and Tyr-294 are, positioned to act as a general base and general acid to promote acetyl, transfer. In addition, this structure provides further evidence that the, N-terminal acetyltransferase domain no longer has enzymatic activity and, is vestigial in nature.

About this StructureAbout this Structure

2C27 is a Single protein structure of sequence from Mycobacterium tuberculosis with ACO, COA and MA8 as ligands. Structure known Active Site: AC1. Full crystallographic information is available from OCA.

ReferenceReference

The substrate-induced conformational change of Mycobacterium tuberculosis mycothiol synthase., Vetting MW, Yu M, Rendle PM, Blanchard JS, J Biol Chem. 2006 Feb 3;281(5):2795-802. Epub 2005 Dec 2. PMID:16326705

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