Asymmetric distribution of phosphatidylethanolamine in the membrane of vesicular stomatitis virus

Abstract

The membrane-impermeable reagent trinitrobenzenesulfonate reacts only with the components of vesicular stomatitis virus (VSV) membranes. When the amount of phosphatidylethanolamine (PE) available to modification by trinitrobenzenesulfonate in intact virions was determined, 36% of the total membrane PE was converted to the trinitrophenyl derivative. The same proportion of the total membrane PE was reactive after removal of the surface glycoprotein by trypsin digestion, but disruption of the virus membrane by sonication rendered all of the PE reactive. PE is apparently asymmetrically distributed in the VSV membrane; 36% is present in the outer lipid leaflet, whereas 64% is found on the inner layer.