Studies on Lysogenization in Escherichia Coli

Although lysogenization was observed over 25 years ago, quantitative studies of the phenomenon have been made only recently (Lieb, 1953; Lwoff, personal communication). The work of E. and J. Lederberg (1953) and of Wollman (1953) has aroused new interest in the nature of the relationship of the prophage to its host. The most logical way to approach this problem is to begin at the meeting of the sensitive bacterial host and a temperate phage. The data to be discussed here, unless otherwise stated, refer to Escherichia coli strain K12S and the temperate phage lambda, carried by lysogenic K12 strains. These strains have been described elsewhere (Weigle and Delbrück, 1951; Lieb, 1953).