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Susceptibility and mode of binding of the Mycobacterium tuberculosis cysteinyl transferase mycothiol ligase to tRNA synthetase inhibitors.

ABSTRACT: The cysteinyl transferase mycothiol ligase, or MshC, catalyzes the fourth step in the biosynthesis of the small molecular weight thiol mycothiol. MshC is essential for growth of Mycobacterium tuberculosis. Two groups of known aminoacyl tRNA synthetase inhibitors were evaluated for inhibition of M. tuberculosis MshC including aminoacyl adenosine analogs and natural products. Using enzyme assays, isothermal titration calorimetry and NMR, we show that MshC is selectively inhibited by cysteinyl sulfamoyl adenosine, and that discrimination occurs at the amino acid moiety.

SUBMITTER: Gutierrez-Lugo MT

PROVIDER: S-EPMC3109356 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Susceptibility and mode of binding of the Mycobacterium tuberculosis cysteinyl transferase mycothiol ligase to tRNA synthetase inhibitors.

Gutierrez-Lugo Maria-Teresa MT Bewley Carole A CA

Bioorganic & medicinal chemistry letters 20110217 8

The cysteinyl transferase mycothiol ligase, or MshC, catalyzes the fourth step in the biosynthesis of the small molecular weight thiol mycothiol. MshC is essential for growth of Mycobacterium tuberculosis. Two groups of known aminoacyl tRNA synthetase inhibitors were evaluated for inhibition of M. tuberculosis MshC including aminoacyl adenosine analogs and natural products. Using enzyme assays, isothermal titration calorimetry and NMR, we show that MshC is selectively inhibited by cysteinyl sulf ...[more]

PMID: 21392992

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