Single-channel parameters of gramicidin a,b, and c |
| |
Authors: | E Bamberg K Noda P Läuger |
| |
Institution: | 1. Department of Biology, University of Konstanz, D-775 Konstanz, G.F.R;2. Section on Molecular Structure, reproduction Research Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Md., 20014 USA |
| |
Abstract: | The single-channel conductance Λ and the mean channel lifetime τ1 of natural and synthetic gramicidins A, B, and C has been studied. Significant differences in Λ were found between gramicidin A and B; both gramicidins differ only in one amino acid (tryptophan replaced by phenylalinine). The distribution of Λ is narrow in glycerylmonooleate membranes but considerably broader in dioleoyl phosphatidylcholine and dioleoyl phosphatidylethanolamine membranes. The ratio of the single-channel conductances in glycerylmonooleate and dioleoyl phosphatidylcholine membranes is only about two and is considerable smaller than the conductance ratio of nonactin-mediated cation transport. This finding suggests that dipolar potentials at the membrane/solution interface have little influence on the conductance of the gramicidin channel. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|