Effects of x-rays on the formation of lactase in a lysogenic strain and a sensitive strain of Escherichia coli.

The process of adaptive enzyme formation has aroused considerable interest through the years. In view of the interesting results of several recent investigations of the effects of radiations on adaptive enzyme formation (Spiegelman et al., 1951; Swenson and Giese, 1950; Brandt et al., 1951; Billen and Lichstein, 1952; Swenson, 1950) it seemed desirable to investigate the effects of x-rays on the adaptive formation of the enzyme in which we are particularly interested, the lactase (0-D-galactosidase) of Escherichia coli. During the course of this study a related problem was encountered, namely the relationship between adaptive enzyme formation and lysogenic phage production, and this also will be considered in this publication.