Role of bacterial nitroreductase and O-acetyltransferase in urine mutagenicity assay of rats exposed to 2,4,6-trinitrotoluene (TNT).
The urine mutagenicity of rats exposed to 2,4,6-trinitrotoluene (TNT) by i.p. injection was studied in the Salmonella assay using indicator strains with various levels of 'classical' nitroreductase or acetyl-CoA:N-hydroxylarylamine O-acetyltransferase activity. The strains used were the conventional Salmonella typhimurium TA98, nitroreductase-deficient TA98NR and -overproducing YG1021, and O-acetyltransferase-deficient TA98/1,8-DNP6 and -overproducing YG1024. TA98, YG1021 and YG1024 clearly detected the increase of direct urine mutagenicity. A slight increase of mutagenicity was also detected with metabolic activation in YG1021 and YG1024. High levels of both nitroreductase and O-acetyltransferase significantly increased the sensitivity of the indicator strain to the mutagenicity of urine caused by TNT exposure, while the nitroreductase- or O-acetyltransferase-deficient strains gave negative responses.
Einistö
P
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Institute of Occupational Health, Helsinki, Finland.
D000123:Acetyltransferases / Q000652:urine*; D000818:Animals; D008297:Male; D009152:Mutagenicity Tests; D009601:Nitroreductases / Q000652:urine*; D051381:Rats; D011919:Rats, Inbred Strains; D014303:Trinitrotoluene / Q000494:pharmacology*
D014303:Trinitrotoluene; D009601:Nitroreductases; D000123:Acetyltransferases