[Distribution of the isoenzymes of nucleases in group A Streptococci (author's transl)].

62 strains of Group A streptococci of different origin were cultured under comparable conditions. The supernatants of cultures of the same optical density were investigated in respect of their DNase activity. After electrophoretic separation in PAA gel, the distribution and activity of the four isoenzymes, B, D, A and C was determined. The total activity showed a near-random distribution, all patterns except B D A were found. DNase B was produced by all, DNase C by one half, DNase A by one third, and DNase D by one fifth of the strains. DNase B alone was found in three out of ten strains. The total DNase-activity and the distribution pattern in strains of the same M serotype but of different origin varied within a wide range. So a further biochemical differentiation of this strain seems to be possible.