Utilization of model membranes in a test for the mechanism of ethylene action.

Reversible alteration of the surface tension of thin films of lipids, proteins and mixtures of both resulted when the thin films were treated with ethylene and other aliphatic gases. This effect appeared to be a nonspecific surface effect related to the molecular size of the gases. Ethylene produced no change which would ascribe to it any specific properties in this test system. The conductivity of an egg lecithin-cholesterol bilayer membrane separating two electrolytes was unaffected by all the test gases (including ethylene), but chloroform vapors markedly altered the conductivity in a reversible manner. In each of the test systems empoloyed, there was no specificity exhibited by ethylene, either qualitatively or quantitatively, indicating the mechanism of ethylene action cannot be explained as a simple physical effect on membranes.