The bacterial response to DNA damage

Abstract Bacteria respond to DNA damage by switching on the SOS system, which promotes DNA repair, mutagenesis and other cellular functions. The basic structure of the system is a set of subordinate genes that are repressed under normal conditions by a single repressor ( lexA protein) and are derepressed by a second regulator ( recA protein) in response to DNA damage. In addition, fine controls and feedback loops may operate to modify the intensity and duration of the SOS response and to permit the differential expression of the subordinate genes.