Lytic Effects of Staphylococcal α-Toxin and δ-Hemolysin

Several preparations of staphylococcal α-toxin and δ-lysin were studied in order to compare hemolytic activity with capacity to lyse bacterial protoplasts. δ-Lysin in relatively low concentration lysed protoplasts of Sarcina lutea, protoplasts of Streptococcus faecalis, and spheroplasts of Escherichia coli. Lysis of bacterial protoplasts by preparations of α-toxin appeared to be due to contamination of the preparations with δ-lysin. Data comparing the protoplast-lysing activity of various lytic agents are presented.