HIV Fusion Peptides Significantly Soften Lipid Bilayers

Abstract

The fusion peptide (FP) of the human immunodeficiency virus (HIV) is found on N-terminus of the viral envelope glycoprotein gp41 and is believed to play an important role in the virus entry process. In order to understand the immediate effect of this peptide on the cell membrane we have studied the influence of the synthetic fusion peptide residue FP-23 on the mechanical properties of model lipid bilayers. For this purpose, giant unilamellar vesicles (GUV) were prepared by electroformation from the unsaturated lipid dioleoylphosphatidylcholine mixed in various ratios with the fusion peptide.