AN INTRACELLULAR HEMOLYSIN OF GROUP A STREPTOCOCCI II

Abstract

Several properties of an intracellular hemolysin of group A streptococci, obtained by sonic disruption of the cells, were determined. This lysin can be readily distinguished from streptolysin O by virtue of the failure of various reagents which are known inhibitors of streptolysin O to influence its activity. The relationship of the intracellular lysin to streptolysin S is more difficult to establish, but the following evidence indicates these lysins are distinct: relative activity on sheep and rabbit cells, the inverse effect which Na and K have on their activity, and the production of intracellular lysin by a strain of group A streptococci which produces very little streptolysin S.