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Characterization of new mutations in pyrazinamide-resistant strains of Mycobacterium tuberculosis and identification of conserved regions important for the catalytic activity of the pyrazinamidase PncA.

ABSTRACT: A new set of mutations, including transposition of the insertion sequence IS6110, was identified in the pncA gene from 19 pyrazinamide-resistant Mycobacterium tuberculosis strains. Alignment of the PncA protein from M. tuberculosis with homologous proteins from different bacterial species revealed three highly conserved regions in PncA which may play an important role in the processing of pyrazinamide.

SUBMITTER: Lemaitre N

PROVIDER: S-EPMC89359 | biostudies-literature | 1999 Jul

REPOSITORIES: biostudies-literature

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Characterization of new mutations in pyrazinamide-resistant strains of Mycobacterium tuberculosis and identification of conserved regions important for the catalytic activity of the pyrazinamidase PncA.

Lemaitre N N Sougakoff W W Truffot-Pernot C C Jarlier V V

Antimicrobial agents and chemotherapy 19990701 7

A new set of mutations, including transposition of the insertion sequence IS6110, was identified in the pncA gene from 19 pyrazinamide-resistant Mycobacterium tuberculosis strains. Alignment of the PncA protein from M. tuberculosis with homologous proteins from different bacterial species revealed three highly conserved regions in PncA which may play an important role in the processing of pyrazinamide. ...[more]

PMID: 10390238

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Association between pncA gene mutations, pyrazinamidase activity, and pyrazinamide susceptibility testing in Mycobacterium tuberculosis.

Project description:We determined MICs for, confirmed the presence of pncA mutations in, and performed pyrazinamidase testing on colonies (subclones) obtained from seven isolates that exhibited differential pyrazinamide (PZA) susceptibility. Six of the seven strains were found to exhibit characteristics resulting from the mixture of strains possessing different properties. In addition, our analysis revealed large pncA-spanning deletions (1,565 bp, 4,475 bp, and 6,258 bp) in three strains that showed high PZA resistance.

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Characterization of pncA mutations in pyrazinamide-resistant Mycobacterium tuberculosis.

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Pyrazinamide Resistance and pncA Mutation Profiles in Multidrug Resistant Mycobacterium Tuberculosis.

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Study of the structure-activity relationships for the pyrazinamidase (PncA) from Mycobacterium tuberculosis.

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| S-EPMC5442549 | biostudies-literature

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