Site-specific deletions of chromosomally located DNA segments with the multimer resolution system of broad-host-range plasmid RP4

The multimer resolution system (mrs) of the broad-host-range plasmid RP4 has been exploited to develop a general method that permits the precise excision of chromosomal segments in a variety of gram-negative bacteria. The procedure is based on the site-specific recombination between two directly repeated 140-bp resolution (res) sequences of RP4 effected by the plasmid-borne resolvase encoded by the parA gene. The efficiency and accuracy of the...