Showing papers on "Ion channel published in 1973"
TL;DR: The dissociation rate constant is equal to 2 sec−1, a value which is consistent with the channel lifetime as obtained from electrical fluctuation measurements, and which is by three orders of magnitude below the limiting value of a diffusion-controlled reaction in a two-dimensional system.
Abstract: Previous studies have given evidence that the active form of gramicidin A in lipid bilayer membranes is a dimer which acts as an ion channel; it has been further shown that the mean lifetime of the channel strongly depends on the membrane thickness. As the thickness slightly decreases when a voltage is applied to the membrane, the equilibrium between conducting dimers and nonconducting monomers may be displaced by a voltage jump. From the relaxation of the electrical current after the voltage jump, information about the kinetics of channel formation is obtained. For a dioleoyllecithin/n-decane membrane the rate constant of association is found to be 2×1014 cm2 mole−1 sec−1, which is by three orders of magnitude below the limiting value of a diffusion-controlled reaction in a two-dimensional system. The dissociation rate constant is equal to 2 sec−1, a value which is consistent with the channel lifetime as obtained from electrical fluctuation measurements.
252 citations