通过差异聚合物分配法确定容积敏感性阴离子通道的孔径

Sizing the pore of the volume-sensitive anion channel by differential polymer partitioning.

作者信息

Ternovsky Vadim I, Okada Yasunobu, Sabirov Ravshan Z

机构信息

Department of Cell Physiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan.

出版信息

FEBS Lett. 2004 Oct 22;576(3):433-6. doi: 10.1016/j.febslet.2004.09.051.

DOI:10.1016/j.febslet.2004.09.051

PMID:15498575

Abstract

Partitioning of ethylene glycol and its polymeric forms into the pore of the volume-sensitive outwardly rectifying (VSOR) anion channel was studied to assess the pore size. Polyethylene glycol (PEG) PEG 200-300 (Rh = 0.27-0.53 nm) effectively suppressed the single-channel currents, whereas PEG 400-4000 (Rh = 0.62-1.91 nm) had little or no effect. Since all the molecules tested effectively decreased electric conductivity of the bulk solution, the observed differential effects between PEG 200-300 and PEG 400-4000 on the VSOR single-channel current are due to their limited partitioning into the channel lumen. The cut-off radius of the VSOR channel pore was assessed to be 0.63 nm.

摘要

为评估体积敏感性外向整流（VSOR）阴离子通道孔的大小，研究了乙二醇及其聚合形式在该通道孔中的分配情况。聚乙二醇（PEG）PEG 200 - 300（流体力学半径Rh = 0.27 - 0.53纳米）能有效抑制单通道电流，而PEG 400 - 4000（Rh = 0.62 - 1.91纳米）几乎没有影响或完全没有影响。由于所有测试分子均有效降低了本体溶液的电导率，所以观察到的PEG 200 - 300和PEG 400 - 4000对VSOR单通道电流的差异效应是由于它们在通道腔内的有限分配。VSOR通道孔的截止半径评估为0.63纳米。