Staphylococcus aureus P83 (ATCC 31890) produces five components, I to V for synergistic toxins, leukocidin and gamma-hemolysin [Sudo et al., Biosci. Biotech. Biochem., 56, 1786-1789 (1995)]. We report here the identification of component II, which is designated LukF-PV(P83) and its gene (lukF-PV(P83)). The lukF-PV(P83) gene was found to be one base downstream of the stop codon of the lukM gene. The deduced amino acid sequence of LukF-PV(P83) showed 78.4% identity with that of LukF-PV. The lukM and lukF-PV(P83) genes were encoded as one operon like that of Panton-Valentine leukocidin.