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Reconstitution of a new cysteine biosynthetic pathway in Mycobacterium tuberculosis.

ABSTRACT: A new pathway for cysteine biosynthesis has been elucidated in Mycobacterium tuberculosis. This pathway involves a protein-bound thiocarboxylate (CysO-SH) as the sulfide donor, similar to thiamin biosynthesis. Cysteine synthase M (CysM) catalyzes the addition of cysteine to the carboxy terminus of the protein-bound thiocarboxylate to generate a CysO-cysteine adduct. A protease, Mec+, hydrolyzes the CysO-cysteine adduct to release cysteine and regenerate CysO. Mec+ contains a JAMM motif, and this work provides the first functional characterization of the JAMM motif in prokaryotes. MoeZ, a paralogue of ThiF, has been shown to transfer sulfur onto CysO.

SUBMITTER: Burns KE

PROVIDER: S-EPMC2536522 | biostudies-literature | 2005 Aug

REPOSITORIES: biostudies-literature

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Reconstitution of a new cysteine biosynthetic pathway in Mycobacterium tuberculosis.

Burns Kristin E KE Baumgart Sabine S Dorrestein Pieter C PC Zhai Huili H McLafferty Fred W FW Begley Tadhg P TP

Journal of the American Chemical Society 20050801 33

A new pathway for cysteine biosynthesis has been elucidated in Mycobacterium tuberculosis. This pathway involves a protein-bound thiocarboxylate (CysO-SH) as the sulfide donor, similar to thiamin biosynthesis. Cysteine synthase M (CysM) catalyzes the addition of cysteine to the carboxy terminus of the protein-bound thiocarboxylate to generate a CysO-cysteine adduct. A protease, Mec+, hydrolyzes the CysO-cysteine adduct to release cysteine and regenerate CysO. Mec+ contains a JAMM motif, and this ...[more]

PMID: 16104727

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