Surface and polarization fluorescence studies on the interaction of an RGD sequence containing a Hepatitis A virus peptide with phospholipids

The synthesis of a VP3(110–121)-HAV peptide was carried out by solid phase methodology. A physicochemical study on the interaction of this peptide with phospholipids involving lipid mono- and bilayers is described. The surface activity of the peptide is indicative of a medium hydrophobic character suggesting the potential ability of this peptide to associate with lipids. Moreover, the presence of the peptide in the incubation media of dipalmitoylphosphatidylcholine (DPPC) and DPPC/DPPG liposomes saturated with anilinonaphthalene sulphonate (ANS) or diphenylhexatriene (DPH) show a strong influence in the bilayers fluidity determined by polarization fluorescence. The presence of lipids in the gel state has a strong influence on the polarity of a Trp environment, inducing a blue shift and fluorescence intensity increases. No interaction was detected when measurements were carried out at temperatures above Tc.