Specificity of base substitution mutations induced by the dietary carcinogens 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in Salmonella

✍ Scribed by W.H. Koch; R.W. Wu; T.A. Cebula; J.S. Felton

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 132 KB
• Volume: 31
• Category: Article
• ISSN: 0893-6692
• DOI: 10.1002/(sici)1098-2280(1998)31:4<327::aid-em4>3.0.co;2-f

✦ Synopsis

The base pair substitution mutational profiles in-position (CCCrCTC; 96-99% of total). Base substiduced by the heterocyclic amine cooked food muta-tution mutagenesis induced by heterocyclic amines gens PhIP and IQ in Salmonella typhimurium strains related to PhIP is generally SOS-dependent, requir-TA100 and TA1535 were determined by colony ing the presence of plasmid pKM101 in Salmonella hybridization analysis. Both PhIP and IQ induced hisG46 strains. Thus, the SOS dependent reversion predominantly GCrTA transversions in strain of S. typhimurium strain TA100 probably reflects TA100 (rfa,DuvrB/pKM101) with a pronounced error-prone lesion bypass at the major PhIP-guanopreference for the second codon position (CCCr sine adduct at the C-8 position. The GCrAT transi-CAC; 72% of total). PhIP also reverted strain tion mutations induced by PhIP in strain TA1535 TA1535 (rfa, DuvrB) efficiently at concentrations appear to be SOS-independent, however, sugsimilar to those required for strain TA100. In con-gesting that these mutations may arise from the fortrast to the PhIP-induced mutational profile observed mation of PhIP-DNA adducts other than the replicain strain TA100, in strain TA1535 PhIP induced ex-tion-blocking C8-dG lesion.