Immunochemical and structural characterization of a serotype-specific polysaccharide antigen from Actinobacillus actinomycetemcomitans Y4 (serotype b).
A serotype-specific polysaccharide antigen of Actinobacillus actinomycetemcomitans Y4 (serotype b) was extracted from whole cells by autoclaving. The extract was purified by chromatography on DEAE-Sephadex A-25 and Sephacryl S-300 columns. The purified polysaccharide antigen formed a single precipitin line with anti-type b serum but not with anti-type a serum and anti-type c serum. The antigen was composed of 43.9% L-rhamnose, 49.1% D-fucose, and a trace amount of fatty acid. Methylation analysis, Smith degradation, and optical rotation data showed that the antigen was a polymer consisting of a disaccharide repeating unit, ----3)-alpha-D-fucopyranosyl-(1----2)-beta-L-rhamnopyranosyl-(1----. In quantitative precipitin inhibition tests, D-fucose and L-rhamnose showed very low inhibition, but the partial hydrolysate of the purified antigen was an effective inhibitor, suggesting that the serotype b specific antiserum recognizes the larger oligosaccharide units.
Amano
K
K
Department of Dental Research, National Institute of Health, Tokyo, Japan.
Nishihara
T
T
Shibuya
N
N
Noguchi
T
T
Koga
T
T
D000188:Actinobacillus / Q000276:immunology*; D000942:Antigens, Bacterial / Q000032:analysis*; D002236:Carbohydrate Conformation; D002852:Chromatography, Ion Exchange; D000939:Epitopes / Q000032:analysis*; D005779:Immunodiffusion; D015394:Molecular Structure; D011135:Polysaccharides, Bacterial / Q000032:analysis*; D011233:Precipitin Tests; D012703:Serotyping
D000942:Antigens, Bacterial; D000939:Epitopes; D011135:Polysaccharides, Bacterial