title: Fluorescence study of the dynamic interaction between E1(145-162) sequence of hepatitis GB virus C and liposomes.
abstract: The physicochemical characterization of the peptide sequence E1(145-162) corresponding to the structural protein E1 of the hepatitis G virus was done by studying its interaction with model membranes. Small unilamellar vesicles (SUVs) of dimyristoylphosphatidylglycerol or dimyristoylphosphatidylcholine were chosen as mimetic membranes. Peptide incorporation and location in the phospholipid bilayer was investigated by fluorescence anisotropy with SUVs labeled with diphenylhexatriene (DPH) or trimethylammonium-DPH. The addition of the peptide E1(145-162) showed significant changes in the anisotropy values of the probe located at the air/water interface. These results indicate that the peptide E1(145-162) preferably interacts with the lipid surface without penetrating inside the bilayer. A series of fluorescence experiments based on tryptophan peptide fluorescence were modeled by means of multivariate curve resolution-alternating least squares (MCR-ALS) algorithm to further study the peptide interaction with bilayers at different temperatures. The preliminary results obtained with MCR-ALS showed how the peptide concentration decay is directly linked to the appearance of a new specie, which corresponds to the lipid-peptide binding. These results provide useful information for the design of synthetic immunopeptides that can be incorporated into a liposomal system with potential to promote a direct delivery of the membrane-incorporated immunogen to the immunocompetent cells, thus increasing the immuno response from the host.
authors.affiliation: Physical Chemistry Department, Faculty of Pharmacy, University of Barcelona, Associated Unit to the CSIC: Peptides and Proteins: Physicochemical Studies, IN2UB Av. Joan XXIII s/n, 08028, Barcelona, Spain. mjesus_sanchez@hotmail.com
authors.forename: Maria Jesús
authors.initials: MJ
authors.lastname: Sánchez-Martín
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Amigo
authors.forename: Montserrat
authors.initials: M
authors.lastname: Pujol
authors.forename: Isabel
authors.initials: I
authors.lastname: Haro
authors.forename: M Asunción
authors.initials: MA
authors.lastname: Alsina
authors.forename: M Antonia
authors.initials: MA
authors.lastname: Busquets
mesh_terms: D000465:Algorithms; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D004161:Diphenylhexatriene / Q000737:chemistry; D005453:Fluorescence; D016018:Least-Squares Analysis; D008051:Lipid Bilayers / Q000737:chemistry; D015999:Multivariate Analysis; D010715:Phosphatidylglycerols / Q000737:chemistry; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D013499:Surface Properties; D013696:Temperature; D050337:Trimethyl Ammonium Compounds / Q000737:chemistry; D053835:Unilamellar Liposomes / Q000737:chemistry*; D014759:Viral Envelope Proteins / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: C087035:E1 protein, Hepatitis C virus; D008051:Lipid Bilayers; D010715:Phosphatidylglycerols; D050337:Trimethyl Ammonium Compounds; D053835:Unilamellar Liposomes; D014759:Viral Envelope Proteins; D004161:Diphenylhexatriene; C002773:dimyristoylphosphatidylglycerol; D004134:Dimyristoylphosphatidylcholine