Substitution of Lysine for Arginine in the N-Terminal 217th Amino Acid Residue of the HγII of Staphylococcal γ-Hemolysin Lowers the Activity of the Toxin

Abstract

The staphyloccocal toxin γ-hemolysin consists of two protein components, LukF and HγII. Staphylococcus aureus P83 was found to have five components, LukF, LukF-PV, LukM, LukS, and HγII for leukocidin orγ-hemolysin. HγII of S. aureus P83 was demonstrated to be a naturally-occurring analogous molecule of HγII [HγII(P83)], in which the 217th arginine residue was replaced by lysine. The HγII(P83) showed about 50% of the hemolytic activity of normal HγII in the presence of LukF.