title: Mutational specificity of 2-nitro-3,4-dimethylimidazo[4,5-f]quinoline in the lacI gene of Escherichia coli.
abstract: 2-Nitro-3,4-dimethylimidazo[4,5-f]quinoline (NO2-MeIQ) is the nitro derivative of 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), one of the food pyrolysis product mutagens and carcinogens. The mutational specificity of NO2-MeIQ was determined using the lacI system in an Escherichia coli strain, EE125, harbouring the plasmid pKM101. NO2-MeIQ acts as a direct-acting mutagen towards this strain, and induces a broad range of mutational alterations. At higher doses; G:C-->T:A transversions dominate the mutational spectrum. Complex mutations were also observed, and the involvement of the SOS system in the processing of the mutations induced by NO2-MeIQ is suggested.
authors.affiliation: Department of Chemistry and Biochemistry, University of Guelph, Ontario, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Kosakarn
authors.forename: J A
authors.initials: JA
authors.lastname: Halliday
authors.forename: B W
authors.initials: BW
authors.lastname: Glickman
authors.forename: P D
authors.initials: PD
authors.lastname: Josephy
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D001482:Base Composition; D001483:Base Sequence; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D007763:Lac Operon; D056968:Lac Repressors; D008969:Molecular Sequence Data; D009153:Mutagens / Q000633:toxicity*; D009154:Mutation; D009593:Nitroimidazoles / Q000633:toxicity*; D011804:Quinolines / Q000633:toxicity*; D012097:Repressor Proteins / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D056968:Lac Repressors; C539064:LacI protein, E coli; D009153:Mutagens; D009593:Nitroimidazoles; D011804:Quinolines; D012097:Repressor Proteins; C064039:3,4-dimethyl-2-nitroimidazo-(4,5-f)quinoline