Involved in DNA double-strand break (DSB) repair (PubMed:18957200). Acts probably with HerA to stimulate resection of the 5' strand and produce the long 3' single-strand that is required for RadA loading (PubMed:18957200). Exhibits 5' endonuclease activity and both 5' and 3' exonuclease activities (PubMed:22064858). Exonuclease activity is stimulated in the presence of HerA. Homodimer (PubMed:22064858). Interacts with HerA (PubMed:18957200). Belongs to the NurA family.