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Electrostatic interactions and hydrogen bond dynamics in chloride pumping by halorhodopsin.

ABSTRACT: Translocation of negatively charged ions across cell membranes by ion pumps raises the question as to how protein interactions control the location and dynamics of the ion. Here we address this question by performing extensive molecular dynamics simulations of wild type and mutant halorhodopsin, a seven-helical transmembrane protein that translocates chloride ions upon light absorption. We find that inter-helical hydrogen bonds mediated by a key arginine group largely govern the dynamics of the protein and water groups coordinating the chloride ion.

SUBMITTER: Jardon-Valadez E

PROVIDER: S-EPMC4315726 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Electrostatic interactions and hydrogen bond dynamics in chloride pumping by halorhodopsin.

Jardón-Valadez Eduardo E Bondar Ana-Nicoleta AN Tobias Douglas J DJ

Biochimica et biophysica acta 20141201 12

Translocation of negatively charged ions across cell membranes by ion pumps raises the question as to how protein interactions control the location and dynamics of the ion. Here we address this question by performing extensive molecular dynamics simulations of wild type and mutant halorhodopsin, a seven-helical transmembrane protein that translocates chloride ions upon light absorption. We find that inter-helical hydrogen bonds mediated by a key arginine group largely govern the dynamics of the ...[more]

PMID: 25256652

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