Serratia Exposed to UV Radiation Show Increase In Survival Capabilities

The recF, recO, and recR genes were originally identified as those affecting the RecF pathway ofrecombination in Escherichia coli cells. Several lines of evidence suggest that the recF, recO, andrecR genes function at the same step of recombination and postreplication repair. In this work,we report that null mutations in recF, recO, or recR greatly reduce UV-radiation mutagenesis(UVM) in an assay for reversion from a Trp (trpE65) to a Trp phenotypes. Introduction of thedefective lexA51 mutation [lexA51(Def)] and/or UmuD' into recF, recO, and recR mutants failedto restore normal UVM in the mutants. On the other hand, the presence of recA2020, asuppressor mutation for recF, recO, and recR mutations, restored normal UVM in recF, recO, andrecR mutants. These results indicate an involvement of the recF, recO, and recR genes and theirproducts in UVM, possibly by affecting the third role of RecA in UVM.