ABSTRACT
On graded hydrolysis and Smith degradation, the O-somatic polysaccharide isolated from Shigella dysenteriae type 10 bacteria yielded four oligosaccharides which were characterized by methylation studies. Immunochemical studies using constituent monosaccharides and the oligosaccharides indicated that the sugar grouping leads to 3)-ManNAc-(1 leads to 3)-Rha-(1 leads to 4)-GlcNAc-(1 leads to was the immunodominant part in the polysaccharide molecule, and that 2-acetamido-2-deoxy-D-mannose contributed maximally to the immunological specificity of the macromolecule.
Subject(s)
Epitopes/analysis , Oligosaccharides/analysis , Polysaccharides, Bacterial/immunology , Shigella dysenteriae/immunology , Carbohydrate Conformation , Carbohydrate Sequence , Precipitin TestsABSTRACT
The lipopolysaccharide isolated from the cells of Shigella boydii type 8 bacteria gave precipitin bands against homologous antisera on Ouchterlony plates, whereas the carbohydrate-containing fractions obtained from it did not. One of the fractions was obtained in major proportion and contained 23.5% of sugars. A structure was assigned to the carbohydrate chain in this material by using the results of methylation, periodate oxidation, and deamination studies.
Subject(s)
Shigella boydii/immunology , Shigella/immunology , Carbohydrate Conformation , Carbohydrate Sequence , Immunodiffusion , Lipopolysaccharides/isolation & purificationABSTRACT
The polysaccharide obtained from the O-somatic antigen of Shigella dysenteriae type 7 (strain NCTC 519/66) contains D-glucose, D-galactose, and 2-acetamido-2-deoxy-D-glucose in the mole ratios of 2:1-1. From the results of methylation, periodate oxidation, graded hydrolysis, and deamination studies, the structure assigned to the repeating unit of the polysaccharide is as follows, (formula: see text) Oxidation studies with chromium trioxide revealed the nature of the anomeric linkages of some of the sugar residues in the polysaccharide.
