Virulence of Mycobacterium tuberculosis after Acquisition of Isoniazid Resistance: Individual Nature of katG Mutants and the Possible Role of AhpC.

ABSTRACT: In the last decade, there were 10 million new tuberculosis cases per year globally. Around 9.5% of these cases were caused by isoniazid resistant (INHr) Mycobacterium tuberculosis (Mtb) strains. Although isoniazid resistance in Mtb is multigenic, mutations in the catalase-peroxidase (katG) gene predominate among the INHr strains. The effect of these drug-resistance-conferring mutations on Mtb fitness and virulence is variable. Here, we assessed differences in bacterial growth, immune response and pathology induced by Mtb strains harboring mutations at the N-terminus of the katG gene. We studied one laboratory and one clinically isolated Mtb clonal pair from different genetic lineages. The INHr strain in each pair had one and two katG mutations with significantly reduced levels of the enzym

SUBMITTER: Nieto R LM 

PROVIDER: S-EPMC5125630 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature