SpxA1 and SpxA2 Act Coordinately To Fine-Tune Stress Responses and Virulence in Streptococcus pyogenes.

ABSTRACT: SpxA is a unique transcriptional regulator highly conserved among members of the phylum Firmicutes that binds RNA polymerase and can act as an antiactivator. Why some Firmicutes members have two highly similar SpxA paralogs is not understood. Here, we show that the SpxA paralogs of the pathogen Streptococcus pyogenes, SpxA1 and SpxA2, act coordinately to regulate virulence by fine-tuning toxin expression and stress resistance. Construction and analysis of mutants revealed that SpxA1^- mutants were defective for growth under aerobic conditions, while SpxA2^- mutants had severely attenuated responses to multiple stresses, including thermal and oxidative stresses. SpxA1^- mutants had enhanced resistance to the cationic antimicrobial molecule

SUBMITTER: Port GC 

PROVIDER: S-EPMC5371413 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature