Chromosome transfer by autonomous transmissible plasmids: the role of the bacterial recombination (rec) system

The ability of autonomous transmissible plasmids or sex factors to transfer chromosomal genes to F(-) recipient bacteria has been investigated by using a series of rec(+) and recA(-) donor strains. It is concluded that chromosome transfer by most sex factors is virtually dependent upon the functional integrity of the bacterial recombination system. However, evidence is presented that suggests the existence of plasmid-specified mechanisms of interaction with the chromosome which are independent of the bacterial recombination system.