title: Purification and characterization of the serotype c antigen from Actinobacillus actinomycetemcomitans.
abstract: The serotype c antigen from Actinobacillus actinomycetemcomitans was purified with fractional ethanol precipitation of cell-free culture supernatant, sequential ion-exchange chromatography, and gel filtration chromatography. The preparation obtained demonstrated a single precipitin line in immunodiffusion, immunoelectrophoresis, and crossed immunoelectrophoresis when rabbit antisera to serotype c whole bacterial cells were used. No immunological reaction was detected with antisera to serotype c lipopolysaccharide, indicating that lipopolysaccharide was not present in the preparation. The serotype c antigen was composed of 95% carbohydrate, 2% protein, and 3.1% phosphate. Gas chromatographic analysis of the antigen obtained from growth in either complex or chemically defined media revealed that the carbohydrate constituent was composed of 84 to 90.1% mannose, 4.8 to 16% glucose, 1.9% N-acetylglucosamine, 1.4% fucose, and 0.2% galactose. The present data suggest that A. actinomycetemcomitans serotype c antigen is predominantly a mannose-containing carbohydrate suggestive of a mannan.
mesh_terms: D000188:Actinobacillus / Q000145:classification / Q000276:immunology*; D000942:Antigens, Bacterial / Q000032:analysis* / Q000276:immunology; D002241:Carbohydrates / Q000032:analysis; D005455:Fluorescent Antibody Technique; D005590:Fractional Precipitation; D005779:Immunodiffusion; D007122:Immunoelectrophoresis; D008358:Mannose / Q000032:analysis; D012703:Serotyping
chemical_list: D000942:Antigens, Bacterial; D002241:Carbohydrates; D008358:Mannose