Detecting carcinogenic and anticancer agents - by different effects on DNA synthesis for mutant and wild bacteria

摘要

Method for detecting potential carcinogens, neutral, toxic and anticancer agents comprises comparing the effect of the test cpd. on in vitro synthesis of DNA isolated from mutant bacteria and from a corresponding wild strain. Carcinogens are recognised because they strongly stimulate synthesis with mutant DNA but not with wild-strain DNA; anticancer agents inhibit initiation of synthesis or chain elongation with mutant DNA but have practically no effect on wild-strain DNA; neutral cpds. have no effect in either case, and toxic substances inhibit synthesis in both cases. Pref. several different mutant-wild strain couples are used; esp. the His- mutant of Salmonella typhimurium and a wild strain; E. coli and its showdomycin-resistant mutant, and DNA isolated from a strain which is resistant to antibiotics and having a specific reactivity in presence of carcinogen or anticancer agent.