Ion Movements in Gramicidin Channels
Current topics in membranes and transportPublished 1 January 1984
Stephen B. Hladky, D.A. Haydon
Citations120
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TL;DR
This chapter discusses gramicidin with respect to its structure and why it is believed to be a channel and its stability and kinetics of formation and decomposition in lipid membranes and in relation to its ion and water permeability.
Abstract
This chapter discusses gramicidin with respect to its structure and why it is believed to be a channel. The gramicidins, of which there are several, are linear 15-amino acid polypeptides produced by Bacillus hreuis. The naturally occurring gramicidin is a mixture of gramicidin A, B, and C in the approximate ratio 72 : 9 : 1. The primary structure of gramicidin A is unusual in several respects. One of the properties of gramicidin that has greatly facilitated its study is its readily measurable single-channel conductance and duration. Unlike the single-channel conductance, both the frequency of opening of channels and the mean channel open time or duration are strong functions of the membrane lipid. The chapter also discusses gramicidins with regard to its stability and kinetics of formation and decomposition in lipid membranes and in relation to its ion and water permeability.
Keywords
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