title: Liposomal cargo unloading induced by pH-sensitive peptides.
abstract: Amphiphilic peptides designed to have a pH-dependent conformational change and membrane activity are described. At physiologic pH, the peptides would exist in a random coil conformation, but at endosomal pH values they would switch to amphiphilic alpha-helices, disrupt membranes, and release liposomal contents. A series of peptides have been investigated that contain a high percentage of Glu residues for the pH-induced conformational switch, and Leu residues for optimal lipid binding. Circular dichroism (CD) results in aqueous and liposomal environments were performed and demonstrate a pH-dependent shift to helicity upon acidification. Liposomal release data at neutral and acidic pH, also document the success of this design strategy.
authors.affiliation: Department of Chemistry, Purdue University, West Lafayette, IN 47906, USA.
authors.forename: H-M
authors.initials: HM
authors.lastname: Lee
authors.forename: J
authors.initials: J
authors.lastname: Chmielewski
mesh_terms: D001665:Binding Sites; D002942:Circular Dichroism; D016503:Drug Delivery Systems; D006863:Hydrogen-Ion Concentration; D008081:Liposomes / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation
chemical_list: D008081:Liposomes; D010455:Peptides