Khozova N A, Suchkov Iu G
Genetika. 1977;13(11):2053-5.
Vitamin-dependent mutants were isolated from Yersinia pestis after the treatment with supermutagens. From 13 mutants obtained 10 appeared to be unstable. The stable vitamin-dependent mutants were revealed with the frequency of 2.5.10(-11) divided by 4.9.10(-11) by the indirect method of selection and 5.10(-7) by the use of Davis's method. The frequency of amino acid and nitrogen base dependent auxotroph isolation was significantly higher than that of the vitamin-dependent mutants.