recFrecOrecR

recFrecOrecR is a genetic locus in the bacterium Escherichia coli that plays a crucial role in DNA replication and repair. The locus contains three genes: recF, recO, and recR. These genes encode proteins that are essential components of the RecFOR pathway, a complex molecular machine involved in homologous recombination and the response to DNA damage.

The RecF, RecO, and RecR proteins work together to load the RecA protein onto single-stranded DNA gaps that arise during replication stalling or DNA breaks. RecA, in its activated form, is central to homologous recombination, facilitating the search for and exchange of DNA sequences. The RecFOR complex specifically helps to initiate RecA loading at these stalled replication forks, thereby promoting fork restart and preventing the accumulation of toxic DNA breaks.

Mutations in any of the recF, recO, or recR genes lead to a severe defect in DNA repair and recombination. Bacteria carrying such mutations are hypersensitive to DNA damaging agents like UV radiation and antibiotics that interfere with replication. The recFrecOrecR locus is therefore a critical element for maintaining genomic stability in E. coli. Understanding its function provides insight into fundamental processes of DNA metabolism.