THE ESTABLISHMENT OF LYSOGENICITY IN ESCHERICHIA COLI

Abstract

When a population of sensitive bacteria is exposed
\nto infection by a temperate phage, a large
\nnumber of cells are not lysed and give rise to
\ncolonies containing lysogenic cells. Some of the
\nfactors influencing the probability that an infected
\ncell of Escherichia coli, strain K12S, will
\ngive a lysogenic response are reported here. In
\naddition, the present study deals with the change
\nof free phage particles into the intracellular
\nprophage form which is transmitted to all cells
\nin a lysogenic culture. Information was obtained
\non specific questions regarding the establishment
\nof lysogenicity, as, for example: When is the
\ndecision as to the type of response, i.e., lytic or
\nlysogenic, made by the infected cell? How much
\ntime is required for transformation (reduction) of
\nthe infecting phage into prophage and what
\nchanges take place in the host cell? Is the prophage
\na cytoplasmic constituent of the lysogenic
\ncell or linked to the genetic mechanism?