Reports

Selfish behavior of restriction-modification systems

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Science  10 Feb 1995:
Vol. 267, Issue 5199, pp. 897-899
DOI: 10.1126/science.7846533

Abstract

Plasmids carrying gene pairs encoding type II DNA restriction endonucleases and their cognate modification enzymes were shown to have increased stability in Escherichia coli. The descendants of cells that had lost these genes appeared unable to modify a sufficient number of recognition sites in their chromosomes to protect them from lethal attack by the remaining restriction enzyme molecules. The capacity of these genes to act as a selfish symbiont is likely to have contributed to the evolution of restriction-modification gene pairs.