title: Chromosomal integration of F' factors in recombination-deficient Hfr strains of Escherichia coli.
abstract: In matings between F' donors and recombination-deficient Hfr recipients, we isolated progeny which transferred both episomal markers and Hfr markers early and with high frequency. A number of these progeny had two integrated sex factors. Investigation of these double Hfr strains showed that the F' nearly always integrated in a homologous region of the chromosome. In any particular mating system integration was specific as to location and direction of chromosome transfer.
mesh_terms: D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D003470:Culture Media; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000254:growth & development / Q000528:radiation effects; D005796:Genes; D005838:Genotype; D007785:Lactose; D009154:Mutation; D010641:Phenotype; D011995:Recombination, Genetic; D013307:Streptomycin; D014466:Ultraviolet Rays
chemical_list: D003470:Culture Media; D004269:DNA, Bacterial; D007785:Lactose; D013307:Streptomycin