Alcohols display a cutoff in a system (gA channels) with no alcohol-binding pocket or steric hindrances, demonstrating that the bilayer-mediated effects of alcohol are more complex than previously thought. Therefore, the presence of an alcohol cutoff does not necessarily provide evidence for a direct protein-alcohol interaction (i.e., the existence of an alcohol-binding site).
The alcohols examined in this study altered the lipid bilayer properties, as measured with a gA-based florescence assay, at concentrations equal to or higher than those reported to cause intoxication (56), similar to those reported to affect various membrane proteins (32), and below those that cause anesthesia (3). This suggests that the biological actions of alcohol likely arise from a combination of specific membrane protein-alcohol interactions, as well as alcohol-induced changes in membrane properties.