Collective diffusion model for water permeation through microscopic channels.

Fangqiang Zhu; Emad Tajkhorshid; Klaus Schulten

doi:10.1103/physrevlett.93.224501

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Collective diffusion model for water permeation through microscopic channels.

Fangqiang Zhu·Emad Tajkhorshid·Klaus Schulten

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Abstract

Water permeation through nanometric channels, generally a coupled many-body process, is described in this study by a single collective coordinate. A collective diffusion model is proposed in which water movement at equilibrium is characterized as an unbiased diffusion along this coordinate and water transport in the presence of a chemical potential difference is described as one-dimensional diffusion in a linear potential. The model allows one to determine the osmotic permeability of a water channel from equilibrium simulations.

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Aquaporins Biological Transport Cell Membrane Permeability Computer Simulation Diffusion Ion Channel Gating Models, Biological Models, Chemical Models, Molecular Molecular Conformation Water Evaluation Study Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.Validation Study

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Fangqiang Zhu, Emad Tajkhorshid, Klaus Schulten. 2004-11-24. Collective diffusion model for water permeation through microscopic channels.. https://doi.org/10.1103/physrevlett.93.224501

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