Analysis of EDTA-soluble cell surface components of gram-positive anaerobic cocci

The protein content of EDTA extracts from 76 strains of Gram-positive anaerobic cocci was examined using SDS-PAGE. Strains of Peptostreptococcus anaerobius produced almost identical profiles; greater heterogeneity was observed within the species Peptococcus magnus, Peptococcus prevotii and Peptococcus asaccharolyticus, but several strains within each biotype produced similar patterns. Serological investigation of these extracts by ELISA revealed numerous cross-reactions among the different biotypes. Immunoblot transfers from polyacrylamide gels demonstrated two common antigens within strains of the species, Ps. anaerobius, but these were not species-specific.