Potassium permeation through the KcsA channel: a density functional study.

Leonardo Guidoni; Paolo Carloni

doi:10.1016/s0005-2736(02)00349-8

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Potassium permeation through the KcsA channel: a density functional study.

Leonardo Guidoni·Paolo Carloni

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Abstract

We present a theoretical study on structural and electronic aspects of K+ permeation through the binding sites of the KcsA channel's selectivity filter. Density functional calculations are carried out on models taken from selected snapshots of a molecular dynamics simulation recently reported [FEBS Lett. 477 (2000) 37]. During the translocation process from one binding site to the other, the coordination number of the permeating K+ ion turns out to decrease and K+ ion polarizes significantly its ligands, backbone carbonyl groups and a water molecule. K+-induced polarization increases significantly at the transition state (TS) between the two binding sites. These findings suggest that polarization effects play a significant role in the microscopic mechanisms regulating potassium permeation.

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Bacterial Proteins Binding Sites Cations, Monovalent Ion Transport Ligands Models, Molecular Potassium Potassium Channels Quantum Theory Streptomyces Journal Article Research Support, U.S. Gov't, P.H.S.

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Leonardo Guidoni, Paolo Carloni. 2002-06-13. Potassium permeation through the KcsA channel: a density functional study.. https://doi.org/10.1016/s0005-2736(02)00349-8

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