title: Evidence for the existence of a family of bacterial nitroreductases capable of activating nitrated polycyclics to mutagens.
abstract: A derivative of Salmonella typhimurium TA98 which does not respond to the potent mutagenicity of 1,8-dinitropyrene is described. This novel strain also shows a lack of response to the mutagenic action of 1,3-dinitropyrene and a greatly reduced response to 1,6-dinitropyrene and 1-nitropyrene. The responses to 1,3,6-trinitropyrene and 1,3,6,8-tetranitropyrene are affected to a much lesser extent. This strain (TA98/1,8DNP6) is fully sensitive to the mutagenicity of 4-nitroquinoline-1-oxide, niridazole, nitroacridine, and nonnitrated frameshift mutagens. This strain appears to be deficient in a nitroreductase which reduces nitrated pyrenes and possibly other nitrated polycyclic aromatic hydrocarbons to corresponding hydroxylamines, the penultimate mutagens.
mesh_terms: D000818:Animals; D001711:Biotransformation; D004352:Drug Resistance, Microbial; D066298:In Vitro Techniques; D009153:Mutagens / Q000378:metabolism*; D009574:Nitro Compounds / Q000378:metabolism; D009601:Nitroreductases; D010088:Oxidoreductases / Q000378:metabolism*; D011083:Polycyclic Compounds / Q000378:metabolism*; D051381:Rats; D012486:Salmonella typhimurium / Q000201:enzymology* / Q000235:genetics
chemical_list: D009153:Mutagens; D009574:Nitro Compounds; D011083:Polycyclic Compounds; D010088:Oxidoreductases; D009601:Nitroreductases