Structural and biochemical characterization of MepR, a multidrug binding transcription regulator of the Staphylococcus aureus multidrug efflux pump MepA.

ABSTRACT: MepR is a multidrug binding transcription regulator that represses expression of the Staphylococcus aureus multidrug efflux pump gene, mepA, as well as its own gene. MepR is induced by multiple cationic toxins, which are also substrates of MepA. In order to understand the gene regulatory and drug-binding mechanisms of MepR, we carried out biochemical, in vivo and structural studies. The 2.40 A resolution structure of drug-free MepR reveals the most open MarR family protein conformation to date, which will require a huge conformational change to bind cognate DNA. DNA-binding data show that MepR uses a dual regulatory binding mode as the repressor binds the mepA operator as a dimer of dimers, but binds the mepR operator as a single dimer. Alignment of the six half sites reveals the consensus

SUBMITTER: Kumaraswami M 

PROVIDER: S-EPMC2651776 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature