Plays a role in DNA repair. It cleaves phosphodiester bonds at apurinic or apyrimidinic sites (AP sites) to produce new 5'-ends that are base-free deoxyribose 5-phosphate residues. Endonucleolytic cleavage to 5'-phosphooligonucleotide end-products. Binds 3 Zn(2+) ions. The C-terminal part is sufficient to function as an AP endonuclease. Belongs to the AP endonuclease 2 family.