PRODUCTION OF RESPIRATION-DEFICIENT MUTANTS IN YEAST BY A CARCINOGEN, 4-NITROQUINOLINE 1-OXIDE

Production of respiration-deficient mutants in very high frequencies was induced by 4-nitroquinoline 1-oxide, a potent carcinogen. The mutant frequency reached 100% in a yeast cell population grown in glucose medium containing 0.7 μg per ml of 4-nitroquinoline 1-oxide. The mutants also appeared in significantly increased frequencies even when 4-nitroquinoline i-oxide was added to glycerol medium which is selective against the mutants and allows only the proliferation of normal cells. Evidence for the induction of cytoplasmic mutation by 4-nitroquinoline 1-oxide is presented. The significance in the investigation of mutagenesis and carcinogenesis is discussed. © 1969.