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Influences of mutations on the electrostatic binding free energies of chloride ions in Escherichia coli ClC.

ABSTRACT: Mutations in ClC channel proteins may cause serious functional changes and even diseases. The function of ClC proteins mainly manifests as Cl(-) transport, which is related to the binding free energies of chloride ions. Therefore, the influence of a mutation on ClC function can be studied by investigating the mutational effect on the binding free energies of chloride ions. The present study provides quantitative and systematic investigations on the influences of residue mutations on the electrostatic binding free energies in Escherichia coli ClC (EcClC) proteins, using all-atom molecular dynamics simulations. It was found that the change of the electrostatic binding free energy decreases linearly with the increase of the residue-chloride ion distance for a mutation. This work reveals how changes in the charge of a mutated residue and in the distance between the mutated residue and the binding site govern the variations in the electrostatic binding free energies and therefore influence the transport of chloride ions and conduction in EcClC. This work would facilitate our understanding of the mutational effects on transport of chloride ions and functions of ClC proteins and provide a guideline to estimate which residue mutations will have great influences on ClC functions.

SUBMITTER: Yu T

PROVIDER: S-EPMC3411325 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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Influences of mutations on the electrostatic binding free energies of chloride ions in Escherichia coli ClC.

Yu Tao T Wang Xiao-Qing XQ Sang Jian-Ping JP Pan Chun-Xu CX Zou Xian-Wu XW Chen Tsung-Yu TY Zou Xiaoqin X

The journal of physical chemistry. B 20120529 22

Mutations in ClC channel proteins may cause serious functional changes and even diseases. The function of ClC proteins mainly manifests as Cl(-) transport, which is related to the binding free energies of chloride ions. Therefore, the influence of a mutation on ClC function can be studied by investigating the mutational effect on the binding free energies of chloride ions. The present study provides quantitative and systematic investigations on the influences of residue mutations on the electros ...[more]

PMID: 22612693

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Influences of mutations on the electrostatic binding free energies of chloride ions in Escherichia coli ClC.

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Influences of mutations on the electrostatic binding free energies of chloride ions in Escherichia coli ClC.

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