Characterisation of antigens extracted from cells and culture fluids of Streptococcus mutans serotype c

Abstract

Two antigens II and III were identified in addition to serotype c and teichoic acid antigens by immunodiffusion and immunoelectrophoresis against rabbit antisera in extracts of Streptococcus mutans (Ingbritt) cells and in hydroxyapatite extracts of culture supernatant (HACS). Two more antigens, I and IV were identified only in HACS but absorption of antisera with cells suggested a cellular location for antigens I, II and III. These antigens have been partially purified by column chromatography on agarose, diethylaminoethyl cellulose and Biogel P150. Antigens II and III were resistant to digestion by trypsin and pronase, while the antigen I specificity was destroyed, suggesting that it contains polypeptide as an integral component, but that II and III do not. Antigens I, II and III were serologically distinct from serotype c polysaccharide and glycerol teichoic acid antigens, and were separable from glucosyltransferase. Evidence was also obtained that antigens I, II and III are not restricted to organisms of serotype c.