Rifampin mechanism

Rifampin, a derivative of rifamycin, is bactericidal against M tuberculosis. The drug inhibits DNA-dependent RNA polymerase (encoded by the rpo gene) in M tuberculosis and many other microorganisms. It has broader spectrum than isoniazid Rifampin blocks transcription by interacting with the β subunit of bacterial, but not human, DNAdependent RNA polymerase and inhibiting mRNA synthesis Resistance via changes in drug sensitivity of the polymerase often emerges rapidly if the drug is used alone.