OXIDATIVE STRESS RESPONSE AND CHARACTERIZATION OF THE OXYR-AHPC AND FURA-KATG LOCI IN MYCOBACTERIUM MARINUM

摘要: Oxidative stress response in pathogenic mycobacteria is believed to be of significance for host-pathogen interactions at various stages infection. It also plays a role determining the intrinsic susceptibility isoniazid mycobacterial species. In this work, we characterized oxyR-ahpC and furA-katG loci nontuberculous pathogen Mycobacterium marinum. contrast smegmatis like tuberculosis leprae, M. marinum was shown possess closely linked divergently oriented equivalents regulator peroxide oxyR its subordinate gene ahpC, encoding homolog alkyl hydroperoxide reductase. Purified OxyR found bind promoter region from additional Mobility shift DNA binding analyses using sites several panel vitro-generated mutants validated proposed consensus recognition sequence. AhpC levels detected by immunoblotting, were increased upon treatment with H2O2, keeping presence functional site within ahpC. contrast, did not sequences upstream katG structural gene, expression follow pattern seen Instead, new open reading frame ferric uptake Fur identified immediately The linkage arrangement are ubiquitous mycobacteria, suggesting regulators oxidative potentially explaining observed differences ahpC expression. Collectively, these findings broaden our understanding mycobacteria. They suggest that will useful as model system studying physiology, intracellular survival, other associated diseases.