A double-stranded DNA virus that infects E. coli. The head of the virus contains a linear DNA molecule 48,514 bp long. However, upon entering the bacterium, the two ends of the DNA molecule become covalently joined to form a circle. Once inside the host cell, the virus can enter either a lytic developmental cycle or a lysogenic cycle. Specific repressors control the switch for either cycle. If the lysogenic cycle is chosen, the virus is eventually integrated into the E. coli chromosome at a specific site. See Chronology, 1950, Lederberg; 1961, Meselson and Weigle; 1965, Rothman; 1967, Taylor, Hradecna, and Szybalski; 1968, Davis and Davidson; 1969, Westmoreland et al., 1974, Murray and Murray; Genome Sizes and Gene Numbers; cro repressor, lambda cloning vector, lambda repressor, lysogenic cycle, lytic cycle, prophage, site-specific recombination, virus.
Subjects: Genetics and Genomics.