title: Photoactivated aflatoxins are mutagens to Salmonella typhimurium and bind covalently to DNA in vitro.
abstract: The mutagenesis of Salmonella typhimurium TA100 and covalent binding in vitro of photoactivated aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2) were investigated. Covalent binding levels of 1140, 225, 330 and 8 pmol aflatoxin per mumol nucleotide phosphate were obtained for AFB1, AFG1, AFB2 and AFG2, respectively, at 50 microM mycotoxin after 2 h of irradiation. Mutant frequencies to histidine prototrophy wre 97, 19, 49 and 0 x 10(-6) for AFB1, AFG1, AFB2 and AFG2 respectively, after 2 h irradiation at 100 microM mycotoxin in the surviving fraction of the mutagenized cultures. Toxicity to Salmonella was 0.59, 0.03, 0.31 and 0 lethal hits under the conditions specified for mutagenesis for AFB1, AFG1, AFB2 and AFG2, respectively.
mesh_terms: D000348:Aflatoxins / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D001711:Biotransformation; D002417:Cattle; D004247:DNA / Q000378:metabolism*; D008027:Light; D009153:Mutagens; D012486:Salmonella typhimurium / Q000187:drug effects* / Q000235:genetics
chemical_list: D000348:Aflatoxins; D009153:Mutagens; D004247:DNA