The Alternative Sigma Factor SigH Regulates Major Components of Oxidative and Heat Stress Responses inMycobacterium tuberculosis

• DOI: 10.1128/jb.183.20.6119-6125.2001
• Publication Date: 2002-07-27T09:58:18Z
• Authors: Sahadevan Raman; Taeksun Song; Xiaoling Puyang; Stoyan Bardarov; William R. Jacobs; Robert N. Husson
• Keywords: Sigma factor; Mycobacterium smegmatis

ABSTRACT Mycobacterium tuberculosis is a specialized intracellular pathogen that must regulate gene expression to overcome stresses produced by host defenses during infection. SigH an alternative sigma factor we have previously shown plays role in the response stress of saprophyte smegmatis . In this work investigated sigH M heat and oxidative stress. We determined mutant more susceptible inducible thioredoxin reductase/thioredoxin genes trxB2/trxC unknown function, Rv2466c, regulated via from promoters directly recognized SigH. also shock dnaK clpB positively The induction these but not other SigH-dependent was markedly greater versus stress, consistent with their additional regulation heat-labile repressor. To further understand response, stress-responsive sigE sigB basal dependent on These data indicate central network regulates oxidative-stress responses are likely be important pathogenesis.