SYNTHESIS, LIPOPHILIC DERIVATIZATION AND INTERACTION WITH LIPOSOMES OF HAV-VP3(102-121) SEQUENCE BY USING SPECTROSCOPIC TECHNIQUES

Hepatitis A virus (HAV) is composed mainly of three structural capsid proteins: VP1, VP2 and VP3, Our group has reported the synthesis and t he immunogenic evaluation of VP3 (110-121) peptide sequence, In the pr esent work, in order to stimulate a T-cell immune response, we have se lected the HAV-VP3 (102-121) peptide which has maximum amphipathicity, Its synthesis was carried out manually in the solid phase and semipre parative HPLC was used for purification of the crude peptide, Finally the purified peptide was characterized by analytical HPLC, amino acid analysis and MS, A palmitoyl derivative of VP3 (102-121) was synthesiz ed to modify the hydrophobicity of the peptide, Both free and lipophil ically derivatized peptides were incorporated into multilamelar liposo mes. Physicochemical studies of the HAV-related peptides described abo ve were carried out using monolayers as membrane models, Compression i sotherms, surface activity and penetration kinetics into dipalmitoylph osphatidylcholine monolayers mere determined, Moreover, changes in the fluidity of bilayers induced by these peptides were determined by mea ns of polarizable probes such as 8-anilino-1-naphthalenesulfonic acid and 1,6-diphenyl-1,3,5-hexatriene. The integrity of the membranes has also been ascertained with the carboxyfluorescein.