Mutagenesis by N-nitroso compounds in Salmonella typhimurium TA102 and TA104: evidence for premutagenic adenine or thymine DNA adducts.
Mutagenesis induced by the N-nitroso compounds: N-nitrosomethylurea, N-nitrosoethylurea, N-nitrosodi-n-propylamine and N-nitrosopyrrolidine was measured in Salmonella typhimurium TA100, TA102 and TA104. TA100 detects damage mainly at G-C base pairs while TA102 and TA104 can detect damage at A-T base pairs. In general all strains were similarly sensitive, except that TA104 was much less sensitive to high doses of N-nitroso-N-methylurea. In TA104 a significant percentage of the revertants induced by all agents except NMU resulted from point mutations at A-T base pairs, indicating that adenine or thymine DNA adducts are important premutagenic adducts formed by certain N-nitroso compounds.
D000225:Adenine; D000818:Animals; D001482:Base Composition; D001711:Biotransformation; D004269:DNA, Bacterial / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D009152:Mutagenicity Tests; D009153:Mutagens; D009154:Mutation; D009603:Nitroso Compounds / Q000494:pharmacology*; D051381:Rats; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics; D013045:Species Specificity; D013329:Structure-Activity Relationship; D013941:Thymine
D004269:DNA, Bacterial; D009153:Mutagens; D009603:Nitroso Compounds; D000225:Adenine; D013941:Thymine