The drug inhibiting DNA-dependent RNA polymerase in Mycobacteria is -: (A) INH, (B) Rifampicin, (C) Ciprofloxacin, (D) Ethionamide
Answer is B. Ans. is 'b' i.e., Rifampicin Mechanism of action of impoant antitubercular drugs o Rifampicin --> Inhibits DNA dependent RNA synthesis by inhibiting RNA polymerase. o INH --> Inhibits synthesis of mycolic acid which is a component of mycobacterial cell wall. o Pyrazinamide --> Inhibits synthesis of mycolic acid. o Streptomycin --> Inhibits protein synthesis (translation). o Ethambutol --> Inhibits incorporation ofmycolic acid into bacterial cell wall by inhibiting arbinosyltransferase.