Rifampicin inactivation by Rhodococcus and Mycobacterium species

When prokaryotes are exposed to inhibitory concentrations of the antibiotic rifampicin, the only means hitherto identified by which cells overcome this inhibition is through mutational alteration in the target moiety, DNA-dependent RNA polymerase. In the nocardioform bacterium Rhodococcus erythropolis a novel mechanism has been identified, consisting of an inducible rifampicin-inactivating mechanism. Changes in the drug absorbance spectrum paralleled the decline in bacteriostatic activity of the antibiotic. © 1987.