[Isolation and characterization of erythrogenic toxins of Streptococcus pyogenes 3. communication: comparative studies of type A erythrogenic toxins (author's transl)].

The production of type A erythrogenic toxin was determined in 11 strains of Streptococcus pyogenes (serological group A). All strains produced this toxin, at quantities varying between 16 mg/l (strain "Smith") and 0.03 mg/l (strain T18). The erythrogenic toxins of 5 strains were purified by adsorption to silicate, elution, precipitation with ammonium sulfate, treatment with calcium phosphate, CM-Sepharose chromatography and gel filtration on Sephacryl S200. The preparations were found to be homogenous in SDS electrophoresis and isoelectric focusing (m.w. between 27 000 an 28 000; i.p. 52). They were serologically identical by immunodiffusion (Ouchterlony), and no spur formation was seen with crude concentrates of the toxins produced by the remainder of the strains.