[Molecular profile of mitogen-active metabolites of Staphylococcus aureus].

A fraction with a molecular weight of 16000-24000 was isolated from 5-day S. aureus broth culture grown in the dialysate of Martin-Hottinger broth. At a concentration of 2-15 micrograms/ml this fraction induced the nonspecific blast transformation of human blood lymphocytes with the stimulation index 99.6 +/- 15.2 (72-hour cultures). The mitogenic fraction was immunochemically inert and unrelated to the main part of biologically active components, resistant to heating at 100 degrees C for 10 minutes and to lyophilization, inactivated (by 84.2%-73.7%) by pronase and trypsin, not inactivated by specific immunosorption. Mitogenically active metabolites are regarded as a separate type of biologically active S. aureus products.