Molecular dynamics studies of ion permeation in VDAC.
Molecular dynamics studies of ion permeation in VDAC.
复制标题
VDAC 中离子渗透的分子动力学研究。
DOI：
10.1016/j.bpj.2010.12.3711
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发表时间：
2011
影响因子：
3.4
通讯作者：
Im,Wonpil
中科院分区：
文献类型：
--
作者：
Rui,Huan;Lee,KyuIl;Pastor,RichardW;Im,Wonpil
The voltage-dependent anion channel (VDAC) in the outer membrane of mitochondria serves an essential role in the transport of metabolites and electrolytes between the cell matrix and mitochondria. To examine its structure, dynamics, and the mechanisms underlying its electrophysiological properties, we performed a total of 1.77μs molecular dynamics simulations of human VDAC isoform 1 in DOPE/DOPC mixed bilayers in 1 M KCl solution with transmembrane potentials of 0, ±25, ±50, ±75, and ±100 mV. The calculated conductance and ion selectivity are in good agreement with the experimental measurements. In addition, ion density distributions inside the channel reveal possible pathways for different ion species. Based on these observations, a mechanism underlying the anion selectivity is proposed; both ion species are transported across the channel, but the rate for K+is smaller than that for Cl−because of the attractive interactions between K+and residues on the channel wall. This difference leads to the anion selectivity of VDAC.
