Conformational and thermodynamic hallmarks of DNA operator site specificity in the copper sensitive operon repressor from Streptomyces lividans.

ABSTRACT: Metal ion homeostasis in bacteria relies on metalloregulatory proteins to upregulate metal resistance genes and enable the organism to preclude metal toxicity. The copper sensitive operon repressor (CsoR) family is widely distributed in bacteria and controls the expression of copper efflux systems. CsoR operator sites consist of G-tract containing pseudopalindromes of which the mechanism of operator binding is poorly understood. Here, we use a structurally characterized CsoR from Streptomyces lividans (CsoR(Sl)) together with three specific operator targets to reveal the salient features pertaining to the mechanism of DNA binding. We reveal that CsoR(Sl) binds to its operator site through a 2-fold axis of symmetry centred on a conserved 5'-TAC/GTA-3' inverted repeat. Operator recognition i

SUBMITTER: Tan BG 

PROVIDER: S-EPMC3902906 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature