[Effect of novoimanine on the cellular permeability indices of staphylococci].

Novoimanine is an antibacterial drug from Hypericum perforatum L. When used in the bacteriostatic concentration, i.e. 0.5 gamma/ml, it induced release of potassium ions from the cells of Staphylococcus aureus 209P and had no effect on release of the UV-absorbing compounds and 14C-amino acids. In addition, incubation of the cells with novoimanine (2.5--50 gamma/ml) provided "preservation" in them of the earlier absorbed 14C-amino acids, while in the control cells their level decreased. In a concentration of 100 gamma/ml novoimanine stimulated activity of ATP-ase and alkaline phosphatase by 34 and 37-57 per cent respectively. Histones F1 and F3 of the calf thymus induced an intensive release of 14C-amino acids from the cells of staphylococci and increased the activity of ATP-ase by 6-10 times. The data of the study suggested that the effect of novoimanine on the cytoplasmic membrane was limited and different from that on the polycationic antibacterial agents.