Establishment of a Salmonella tester strain highly sensitive to mutagenic heterocyclic amines

A co-expression plasmid (p1A2OR) carrying human CYP1A2 and NADPH-P450 reduc tase cDNAs and an expression plasmid (pOAT) carrying Salmonella TA1538/ARO cells. The CYP and OAT expressed in the Salmonella cells showed catalytic a ctivity. The TA1538/ARO strain exhibited high sensitivity to heterocyclic a mines (HCAs) such as 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2- amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,8-dimenthylimidazo[4, 5-f]quinoline (MeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhI P) as compared with the parent Ames tester strain TA1538. It is suggested t hat the intracellular expression of drug-metabolising enzymes makes the Sal monella cells highly sensitive to the HCAs. (C) 1999 Elsevier Science Irela nd Ltd. All rights reserved.