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The structure and mechanism of the Mycobacterium tuberculosis cyclodityrosine synthetase.

ABSTRACT: The Mycobacterium tuberculosis enzyme Rv2275 catalyzes the formation of cyclo(L-Tyr-L-Tyr) using two molecules of Tyr-tRNA(Tyr) as substrates. The three-dimensional (3D) structure of Rv2275 was determined to 2.0-Å resolution, revealing that Rv2275 is structurally related to the class Ic aminoacyl-tRNA synthetase family of enzymes. Mutagenesis and radioactive labeling suggests a covalent intermediate in which L-tyrosine is transferred from Tyr-tRNA(Tyr) to an active site serine (Ser88) by transesterification with Glu233 serving as a critical base, catalyzing dipeptide bond formation.

SUBMITTER: Vetting MW

PROVIDER: S-EPMC2957485 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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The structure and mechanism of the Mycobacterium tuberculosis cyclodityrosine synthetase.

Vetting Matthew W MW Hegde Subray S SS Blanchard John S JS

Nature chemical biology 20100919 11

The Mycobacterium tuberculosis enzyme Rv2275 catalyzes the formation of cyclo(L-Tyr-L-Tyr) using two molecules of Tyr-tRNA(Tyr) as substrates. The three-dimensional (3D) structure of Rv2275 was determined to 2.0-Å resolution, revealing that Rv2275 is structurally related to the class Ic aminoacyl-tRNA synthetase family of enzymes. Mutagenesis and radioactive labeling suggests a covalent intermediate in which L-tyrosine is transferred from Tyr-tRNA(Tyr) to an active site serine (Ser88) by transes ...[more]

PMID: 20852636

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