N-[2-Naphthyl]-glycine hydrazide,a potent inhibitor of DNA-dependent RNA polymerase ofMycobacterium tuberculosis H37RV

N-2-Naphthyl]-glycine hydrazide has been shown for the first time as a potent inhibitor of the DNA-dependent RNA polymerase (EC 2.7.7.6) ofMycobacterium tuberculosis H₃₇R_v. At a concentration of 10^-9 M, the compound shows maximum inhibition of the enzyme, the inhibition being less at higher concentrations. It is suggested that the novel type of inhibition pattern may be due to hydrophobic interactions occurring between the molecules of the compound at higher concentrations. The finding that there is a shift in the λ_max of the compound could also account for this phenomenon. The effect of this compound was also tested on DNA-dependent RNA polymerases from an eukaryotic fungus,Microsporum canis. At a concentration of 10⁻⁹ M it inhibits RNA polymerase II (32%) but not RNA polymerasesI andIII