<prompt> The drug inhibiting DNA-dependent RNA polymerase in Mycobacteria is -INHRifampicinCiprofloxacinEthionamide  <response>: 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. 