title: Crossover sites cix for inversion of the invertible DNA segment C on the bacteriophage P7 genome.
abstract: The bacteriophage P7 genome contains an invertible DNA segment called C which determines its host range. P7 C(+) phages produce plaques on Escherichia coli K12. The C segment consists of a 3-kb unique sequence and 0.62-kb inverted repeats of which one carries an internal 0.2-kb deletion. This deletion has been mapped within the right inverted repeat in the C(+) orientation. The crossover sites cix for inversion of the C segment do not map at the inside boundaries of the inverted repeats, as had been proposed. They are localized at the external ends of these repeats. Thus organization of the C segment in phage P7 is analogous to that in the related phage P1.
mesh_terms: D001483:Base Sequence; D007446:Chromosome Inversion; D003434:Crossing Over, Genetic; D004262:DNA Restriction Enzymes; D004279:DNA, Viral / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D005814:Genes, Viral; D013604:T-Phages / Q000235:genetics*
chemical_list: D004279:DNA, Viral; D004262:DNA Restriction Enzymes