Hemolytic Properties of Whole Cultures and of Sediments of Hemolytic Streptococci

Abstract

Bordet1 observed that in rabbits dying of streptococcus septicemia some lysis in the blood frequently occurred. Besredka 2 demonstrated the presence of a filtrable hemolytic substance or streptolysin in broth cultures of a certain streptococci. The mechanism of the action of streptolysin was carefully studied by Ruediger,3 who found that serum encouraged its production; that it is inactivated or destroyed at 70 C. for 2 hours; that it gradually deteriorates at room temperature but rapidly at incubator temperature; that it may be preserved for some time in the icebox; that it is destroyed by peptic digestion and is not dialysable. The serum of some animals contain antistreptolysin, but this is not increased by immunization. He concluded that the streptolysin possessed a haptophore and a toxophore group. Since the work of Ruediger, little has been added to our knowledge of the mechanism of the action of streptolysin. Van Hellens 4 states that streptolysin is heat resistant. Mishulow 5 noted the sudden disappearance of hemolytic power at icebox temperature. De Kruif and Ireland6 have studied the effect of the concentration of various serums on its production, and also the relationship of outpouring of streptolysin with the logarithmic period of growth. In all their work, supernatant fluids obtained by centrifuging cultures at high speed was substituted for filtration. The phenomenon of lytic action of sediments and of whole broth cultures of varying ages was not investigated especially by them, but they assumed it to be due to the same hemotoxin acting at the surface of the organism. Our object was to study the phenomena of lysis by sediments and whole broth cultures of hemolytic streptococci using plain broth and serum broth of different ages and comparing the results, using varying amounts of red blood cell suspension. We have studied supernatant fluids simultaneously.