[The production of streptolysin O by beta-hemolytic streptococci of group A (author's transl))].

128 M- and 15 T-typed strains of A-streptococci were investigated in respect of their streptolysin O production. The peak of streptolysin O production was reached after the logarithmic growth-phase and persisted for more than 24 h. The strains were classified in very weak 44% (0-1,0 E/ml), weak 30% (1,5-3,0 E/ml), medium 21% (4-8,0 E/ml) strong 5% (12-48 E/ml), 9 strains (7%) produced no detectable streptolysin O. The amount of streptolysin O necessary for antigen stimulation is discussed. A connection of growth character and enzyme production was not observed.