Interaction of human immunodeficiency virus (HIV-1) fusion peptides with artificial lipid membranes.

The interaction of 11 overlapping synthetic peptides corresponding to N-terminal segment of HIV transmembrane glycoprotein gp41 (fusion domain) with artificial lipid membranes has been studied. For this purpose the increase of a bilayer lipid membrane (BLM) conductivity and the changes in ESR spectra of spin-labelled liposomes were registrated. Peptide fragment 523-532 gp160 (BRU strain) had the critical length with regard to channel-forming activity on BLM. The degree of such membranotropic action increased simultaneously with the growth of peptide length and the temperature in the cell. Peptides 518-532 and 517-532 lysed TEMPOcholine-containing liposomes at 37 degrees C. The significance of observed effects for explanation of the mechanism of HIV-induced membrane fusion is discussed.