The YaaA protein of the Escherichia coli OxyR regulon lessens hydrogen peroxide toxicity by diminishing the amount of intracellular unincorporated iron.

ABSTRACT: Hydrogen peroxide (H(2)O(2)) is commonly formed in microbial habitats by either chemical oxidation processes or host defense responses. H(2)O(2) can penetrate membranes and damage key intracellular biomolecules, including DNA and iron-dependent enzymes. Bacteria defend themselves against this H(2)O(2) by inducing a regulon that engages multiple defensive strategies. A previous microarray study suggested that yaaA, an uncharacterized gene found in many bacteria, was induced by H(2)O(2) in Escherichia coli as part of its OxyR regulon. Here we confirm that yaaA is a key element of the stress response to H(2)O(2). In a catalase/peroxidase-deficient (Hpx(-)) background, yaaA deletion mutants grew poorly, filamented extensively, and lost substantial viability when they were cultured in aerobic L

SUBMITTER: Liu Y 

PROVIDER: S-EPMC3133076 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature