Mechanism of the Antibiotic Action of Certain Quinones

Abstract

The mode of antibiotic action of the quinones is complex. This is supported by the fact that some of the quinones with strongest bacteriostatie potency on Staphylococcus have very little effect on Escheri-chia coli or on some spp. of yeast as Saccharomyces cerevisiae or Torula utilis, while other quinone derivatives, whose toxicity on Staphylococcus is quite negligible, exert rather strong effects on the other organisms above. In expts. with Planaria gonocephala, using 1 conapd., it was possible to distinguish 2 dominant factors, progressing from higher to lower cones. of the toxic agent. It is suggested that the effect of higher cones. of the quinones is dominantly due to the tanning property of these compds., while in lower cones, the quinones exert their antibiotic effects by the inhibition of some enzyme of the organism, most probably some of the oxidation-reduction enzymes. The antibiotic effect is not due to a single reaction, but to a very complex mechanism.