title: Characterization of liposomes coated with S-layer proteins from lactobacilli.
abstract: The stability of liposomes coated with S-layer proteins from Lactobacillus brevis and Lactobacillus kefir was analyzed as a previous stage to the development of a vaccine vehicle for oral administration. The interactions of the different S-layer proteins with positively charged liposomes prepared with soybean lecithin or dipalmitoylphosphatidylcholine were studied by means of the variation of the Z potential at different protein-lipid ratios, showing that both proteins were able to attach in a greater extent to the surface of soybean lecithin liposomes. The capacity of these particles to retain carboxyfluorescein or calcein by exposure to bile salts, pancreatic extract, pH change and after a thermal shock showed that both S-layer proteins increased the stability of the liposomes in the same magnitude. The non-glycosylated protein from L. brevis protects more efficiently the liposomes at pH 7 than those from L. kefir even without treatment with glutaraldehyde.
authors.affiliation: Laboratorio de Microbiología Molecular, Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Hollmann
authors.forename: L
authors.initials: L
authors.lastname: Delfederico
authors.forename: G
authors.initials: G
authors.lastname: Glikmann
authors.forename: G
authors.initials: G
authors.lastname: De Antoni
authors.forename: L
authors.initials: L
authors.lastname: Semorile
authors.forename: E A
authors.initials: EA
authors.lastname: Disalvo
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D001647:Bile Acids and Salts / Q000494:pharmacology; D002021:Buffers; D003432:Cross-Linking Reagents / Q000494:pharmacology; D005452:Fluoresceins / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D005765:Gastrointestinal Agents / Q000494:pharmacology; D005976:Glutaral / Q000494:pharmacology; D006358:Hot Temperature / Q000009:adverse effects; D006863:Hydrogen-Ion Concentration; D007778:Lactobacillus / Q000737:chemistry* / Q000235:genetics; D008081:Liposomes / Q000737:chemistry*; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000378:metabolism*; D046529:Microscopy, Electron, Transmission; D010184:Pancreatic Extracts / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D001647:Bile Acids and Salts; D002021:Buffers; D003432:Cross-Linking Reagents; D005452:Fluoresceins; D005456:Fluorescent Dyes; D005765:Gastrointestinal Agents; D008081:Liposomes; D008562:Membrane Glycoproteins; D010184:Pancreatic Extracts; C055764:S-layer proteins; C024098:6-carboxyfluorescein; D005976:Glutaral; C007740:fluorexon