Conformational dynamics of the nucleotide binding domains and the power stroke of a heterodimeric ABC transporter.

ABSTRACT: Multidrug ATP binding cassette (ABC) exporters are ubiquitous ABC transporters that extrude cytotoxic molecules across cell membranes. Despite recent progress in structure determination of these transporters, the conformational motion that transduces the energy of ATP hydrolysis to the work of substrate translocation remains undefined. Here, we have investigated the conformational cycle of BmrCD, a representative of the heterodimer family of ABC exporters that have an intrinsically impaired nucleotide binding site. We measured distances between pairs of spin labels monitoring the movement of the nucleotide binding (NBD) and transmembrane domains (TMD). The results expose previously unobserved structural intermediates of the NBDs arising from asymmetric configuration of catalytically inequi

SUBMITTER: Mishra S 

PROVIDER: S-EPMC4046567 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature