Probing alamethicin channels with water-soluble polymers. Effect on conductance of channel states

摘要: Channel access resistance has been measured to estimate the characteristic size of a single ion channel. We compare channel conductance in presence nonpenetrating water-soluble polymers with that obtained for polymer-free electrolyte solution. The contribution total alamethicin is approximately 10% first three open levels. radii inferred these levels from are 6.3, 10.3, and 11.4 A. dependence on polymer molecular weight also allows evaluation dimensions exclusion. Despite varying conductance, it was shown steric at different remain unchanged. These results support model as an array closely packed parallel pores nearly uniform diameter.