title: Influence of lipidation of GBV-C/HGV NS3 (513-522) and (505-514) peptide sequences on its interaction with mono and bilayers.
abstract: Two decapeptide fragments of the non-structural hepatitis G NS3 protein (GBV-C/HGV), 513-522 (RGRTGRGRSG) and 505-514 (SAELSMQRRG), as well as their palmitoylated derivatives were synthesized. The physico-chemical properties of the peptides were analyzed in both the absence and presence of the zwitterionic 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC), the negative 1,2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (DPPG) and the positive 1,2-dioeloyl-3-trimethylammonium-propane (DOTAP) lipid monolayers. Based on their high hydrophilic properties, neither parent peptide presented surface activity and their incorporation into lipid monolayers was low. In contrast, their palmitoylated derivatives showed concentration-dependent surface activity and could be inserted into lipid monolayers to varying degrees depending on their sequence. Compression isotherms showed that the presence of palmitoylated peptides in the subphase resulted in a molecular arrangement less condensed than that corresponding to the pure phospholipid. In concordance with the monolayer results, differential scanning calorimetry (DSC) demonstrated that the parent peptides did not have any effect on the thermograms, while the palmitoylated derivatives affected the thermotropic properties of DPPC bilayers.
authors.affiliation: Physical Chemistry Department, Faculty of Pharmacy, University of Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain. weronski@ub.edu
authors.forename: Konrad
authors.initials: K
authors.lastname: Weroński
authors.forename: M Antónia
authors.initials: MA
authors.lastname: Busquets
authors.forename: Victória
authors.initials: V
authors.lastname: Girona
authors.forename: Josefina
authors.initials: J
authors.lastname: Prat
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D000465:Algorithms; D002152:Calorimetry, Differential Scanning; D005229:Fatty Acids, Monounsaturated / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry; D010715:Phosphatidylglycerols / Q000737:chemistry; D011312:Pressure; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D013499:Surface Properties; D013816:Thermodynamics; D017361:Viral Nonstructural Proteins / Q000138:chemical synthesis / Q000737:chemistry*; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D015060:1,2-Dipalmitoylphosphatidylcholine; D005229:Fatty Acids, Monounsaturated; D008051:Lipid Bilayers; D008055:Lipids; D010455:Peptides; D010715:Phosphatidylglycerols; D000644:Quaternary Ammonium Compounds; D017361:Viral Nonstructural Proteins; C084422:NS3 protein, hepatitis C virus; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; C070046:1,2-dioleoyloxy-3-(trimethylammonium)propane; C030345:1,2-dipalmitoylphosphatidylglycerol