Diagnostic utilization of hemolytically active exosubstances of certain gram-positive bacteria. I. Detection of staphylococcal hemolysins with prepurified preparations of staphylococcal beta-toxin and CAMP-factor of Streptococcus agalactiae

The authors have modified the one-plate method for the detection of staphylococcal hemolysins. They recommend to use in this method a prepurified form of staphylococcal beta-toxin and of streptococcal CAMP-factor instead of the exclusively beta-tonin-producing strain of Staphylococcus aureus and instead of the intensively CAMP-test positive Streptococcus agalactiae strain, respectively. The authors determined concurrently staphylococcal hemolysins, using a three-plate method in which alpha-antitoxin was employed, to ensure a better evidence of alpha-toxin. A total of 494 staphylococcal strains were examined by both methods. Of this number, 446 Staphylococcus aureus strains were of diverse host origin and 48 were coagulase-negative staphylococcal strains. On the basis of the various hemolytically active staphylococcal toxins, the authors recommend the suggested modification of the one-plate method for their routine detection.