13C NMR detects conformational change in the 100-kD membrane transporter ClC-ec1.

ABSTRACT: CLC transporters catalyze the exchange of Cl(-) for H(+) across cellular membranes. To do so, they must couple Cl(-) and H(+) binding and unbinding to protein conformational change. However, the sole conformational changes distinguished crystallographically are small movements of a glutamate side chain that locally gates the ion-transport pathways. Therefore, our understanding of whether and how global protein dynamics contribute to the exchange mechanism has been severely limited. To overcome the limitations of crystallography, we used solution-state (13)C-methyl NMR with labels on methionine, lysine, and engineered cysteine residues to investigate substrate (H(+)) dependent conformational change outside the restraints of crystallization. We show that methyl labels in several regions repo

SUBMITTER: Abraham SJ 

PROVIDER: S-EPMC4398623 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature