Chromosomal transformation of Escherichia coli recD strains with linearized plasmids

Abstract
Wild-type Escherichia coli are resistant to genetic transformation by purified linear DNA, probably in part because of exonuclease activity. We demonstrate that E. coli containing a recD mutation could be easily transformed by linearized plasmids containing a selectable marker. The marker was transferred to the chromosome by homologous recombination, whereas plasmid markers not in the region of homology were lost.