Chemical and Immunological Characterization of a Novel Amphipathic Antigen from Biotype B Streptococcus sanguis Yamamoto, Toshiko and O Koga, Toshihik and Mizuno, Junn and Hamada, Shigeyuki,, 131, 1981-1988 (1985), doi = https://doi.org/10.1099/00221287-131-8-1981, publicationName = Microbiology Society, issn = 1350-0872, abstract= Summary: A new type of amphipathic antigen was extracted from whole cells of Streptococcus sanguis ATCC 10557 (biotype B, serotype II) by the phenol/water method. The extract was treated with nuclease P1, and was applied to a column of Sepharose 6B. Each fraction was checked by passive haemagglutination (PHA) and immunodiffusion tests against anti-10557 serum which was obtained by immunizing rabbits with whole cells of strain ATCC 10557. Strong PHA activity was demonstrated in the first hexose-containing peak (peak 1) eluted near the void volume, while the second hexose-containing peak (peak 2) produced a heavy band against anti-10557 serum in an immunodiffusion test. The third peak (peak 3) which partially overlapped with peak 2 reacted with concanavalin A, but not with the antiserum, in agar gel. Peaks 2 and 3 had no PHA activity. Peak 1 contained only 1% phosphorus, indicating that cells of strain ATCC 10557 possess an amphipathic antigen which differs from the lipoteichoic acids that are common in many Gram-positive bacteria. Peak 1 was a fatty acid-substituted heteropolysac-charide composed of glucose, galactose, mannose, glycerol and fatty acids in a molar ratio of approximately 1·0 :1·3 : 2·7 : 0·3 : 1·0. PHA activity was inhibited in the presence of polymerized mannose. Peak 2 was composed of glucose, galactose, rhamnose and N-acetylgalactosamine in a molar ratio of approximately 1·0:1·4:0·8:0·8, which was essentially identical to the serotype II carbohydrate antigen reported previously., language=, type=