SarA Represses agr Operon Expression in a Purified In Vitro Staphylococcus aureus Transcription System
AUTOR(ES)
Chakrabarti, Swarup K.
FONTE
American Society for Microbiology
RESUMO
Mutation and genetic complementation studies suggested that two chromosomal loci, agr and sar, are involved in the upregulation of several exotoxin genes and the downregulation of a number of surface protein genes in a growth phase-dependent manner in Staphylococcus aureus. We purified recombinant T7-tagged SarA from Escherichia coli and determined its effect on transcription from several S. aureus promoters by using purified RNA polymerase reconstituted with either ςA or ςB from S. aureus. Of the seven ςA-dependent promoters that we tested, SarA repressed transcription from agrP2, agrP3, cna, sarP1, and sea promoters and did not affect sec and znt promoters. Furthermore, SarA had no effect on transcription from the ςB-dependent sarP3 promoter. In vitro experimental data presented in this report suggest that SarA expression is autoregulated.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=94714Documentos Relacionados
- Regulation of Staphylococcus aureus Capsular Polysaccharide Expression by agr and sarA
- Transcription Profiling-Based Identification of Staphylococcus aureus Genes Regulated by the agr and/or sarA Loci
- Cloning and sequencing of sarA of Staphylococcus aureus, a gene required for the expression of agr.
- Strain-Dependent Differences in the Regulatory Roles of sarA and agr in Staphylococcus aureus
- SarS, a SarA Homolog Repressible by agr, Is an Activator of Protein A Synthesis in Staphylococcus aureus