title: [Study of a specific polyoside and a group antigen extracted from Leptospira biflexa patoc, patoc I strain].
abstract: We extracted from L. biflexa patoc a fraction F, reacting in hemagglutination and ring tests with sera prepared against more than ten different serogroups. This fraction contains mainly a polysaccharide (65 per cent), the role of which was clearly demonstrated in the precipitation reaction with homologous antisera, through periodic oxidation; it also contains lipids (20 per cent) and proteins (10 per cent). We isolated from this fraction F, by Biogel column chromatography, 2 distinct antigens, one, F2, carrying the patoc-type specificity, the other, F 1B, a group specificity shared by many leptospira. These antigens differ not only immunogically, but also in their chemical composition. The type-specific antigen F2 contains mainly a polysaccharide composed of arabinose and glucosamine (possibly an immunodominant sugar). As for the group-specific fraction F 1B, its composition is more complex since lipids and proteins are also found with the polysaccharide. This antigen could therefore be a lipoglycoprotein.
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000032:analysis* / Q000302:isolation & purification; D000939:Epitopes; D005944:Glucosamine / Q000032:analysis; D006386:Hemagglutination Tests; D006801:Humans; D005779:Immunodiffusion; D007919:Leptospira / Q000276:immunology*; D008055:Lipids / Q000032:analysis; D009005:Monosaccharides / Q000032:analysis; D011135:Polysaccharides, Bacterial / Q000032:analysis; D011817:Rabbits; D013045:Species Specificity
chemical_list: D000942:Antigens, Bacterial; D000939:Epitopes; D008055:Lipids; D009005:Monosaccharides; D011135:Polysaccharides, Bacterial; D005944:Glucosamine
vernacular_title: Etude d'un polyoside spécifique et d'un antigène de groupe extraits de Leptospira biflexa patoc, souche patoc I