Coordinated regulation by AgrA, SarA, and SarR to control agr expression in Staphylococcus aureus.

ABSTRACT: The agr locus of Staphylococcus aureus is composed of two divergent transcripts (RNAII and RNAIII) driven by the P2 and P3 promoters. The P2-P3 intergenic region comprises the SarA/SarR binding sites and the four AgrA boxes to which AgrA binds. We reported here the role of AgrA, SarA, and SarR on agr P2 and P3 transcription. Using real-time reverse transcription (RT)-PCR and promoter fusion studies with selected single, double, triple, and complemented mutants, we showed that AgrA is indispensable to agr P2 and P3 transcription, whereas SarA activates and SarR represses P2 transcription. In vitro runoff transcription assays revealed that AgrA alone promoted transcription from the agr P2 promoter, with SarA enhancing it and SarR inhibiting agr P2 transcription in the presence of AgrA or wit

SUBMITTER: Reyes D 

PROVIDER: S-EPMC3194896 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature