title: Heterogeneity of Shigella sonnei phase I O-antigen.
abstract: Shigella sonnei phase I and phase II lipopolysaccharides were examined using passive hemagglutination, immunodiffusion and immunoelectrophoresis. Moreover, O-antigen preparations of phase I obtained by three different methods were separated in SDS polyacrylamide gel electrophoresis into two fractions: L1 and L2, whereas phase II lipopolysaccharide showed one fraction (LI) only. The results of the serological investigations of three mentioned above preparations indicate that the heterogeneity of phase I O-antigen is natural, and not caused by extraction procedures. Shigella sonnei phase I cells produce two types of lipopolysaccharide molecules: I) with core regions substituted by phase I-specific polysaccharide chains, and 2) with core regions unsubstituted, having phase II specificity.
mesh_terms: D000942:Antigens, Bacterial / Q000032:analysis*; D000939:Epitopes; D008070:Lipopolysaccharides / Q000276:immunology; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D012764:Shigella sonnei / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D000939:Epitopes; D008070:Lipopolysaccharides; D011135:Polysaccharides, Bacterial