Biochemical Studies on Streptolysin S Formation*

Abstract
In vitro formation of oligoribonucleotidestreptolysin S complex from serum- or albumin- SLS was described. Evidence indicates that the reaction is due to the transfer of the hemolytic group of serum- or albumin-SLS to oligoribonucleotidc. The hemolytic group, labeled with CM-amino acids, of oligoribonucleotide- streptolysin S complex could be also transferred to serum but not to albumin. These hemolysin complexes formed in vitro by the transfer had the same properties as that of the corresponding hemolysins formed in vivo by resting cell system. Thus it was concluded that the oxygenstable streptococcal hemolysins are complexes composed of a prosthetic group of polypeptide nature, identical with the hemolytic moiety of intracellular streptolysin S, and certain carrier substances such as AF, serum and albumin which act as the extractor of streptolysin S from cells as well.