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. 1998 Dec;75(6):2767–2782. doi: 10.1016/S0006-3495(98)77720-3

Dynamic properties of Na+ ions in models of ion channels: a molecular dynamics study.

G R Smith 1, M S Sansom 1
PMCID: PMC1299950  PMID: 9826599

Abstract

We present simulation results for the effective diffusion coefficients of a sodium ion in a series of model ion channels of different diameters and hydrophobicities, including models of alamethicin, a leucine-serine peptide, and the M2 helix bundle of the nicotinic acetylcholine receptor. The diffusion coefficient, which in the simulations has a value of 0.15(2) A2ps-1 in bulk water, is found to be reduced to as little as 0.02(1) A2ps-1 in the narrower channels, and to about 0.10(5) A2ps-1 in wider channels such as the nicotinic acetylcholine receptor. It is anticipated that this work will be useful in connection with calculations of channel conductivity using such techniques as the Poisson-Nernst-Planck equation, Eyring rate theory, or Brownian dynamics.

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Selected References

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