Modulating the Chemical Transport Properties of a Transmembrane Antiporter via Alternative Anion Flux.

ABSTRACT: ClC-ec1 is a prototype of the ClC antiporters, proteins that stoichiometrically exchange Cl^- and H⁺ ions in opposite directions across a membrane. It has been shown that other polyatomic anions, such as NO₃^- and SCN^-, can also be transported by ClC-ec1, but with partially or completely uncoupled proton flux. Herein, with the help of multiscale computer simulations in which the Grotthuss mechanism of proton transport (PT) is treated explicitly, we demonstrate how the chemical nature of these anions alters the coupling mechanism and qualitatively explain the shifts in the ion stoichiometry. Multidimensional free energy profiles for PT and the coupled changes in hydration are presented for NO₃^- and SCN^-. T

SUBMITTER: Wang Z 

PROVIDER: S-EPMC6379079 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature