DNA-(Apurinic or Apyrimidinic Site) Lyase

**Definition:** A DNA repair enzyme that catalyses the excision of ribose residues at apurinic and apyrimidinic DNA sites that can result from the action of DNA GLYCOSYLASES. The enzyme catalyzes a beta-elimination reaction in which the C-O-P bond 3' to the apurinic or apyrimidinic site in DNA is broken, leaving a 3'-terminal unsaturated sugar and a product with a terminal 5'-phosphate. This enzyme was previously listed under EC 3.1.25.2.

**Tree numbers:** - D08.811.074.750 - D08.811.520.241.225

**Synonyms:** - DNA Lyase (Apurinic or Apyrimidinic) - AP Endonuclease - AP Lyase - Apurine-Apyrimidine Endonuclease - Apurinic DNA Endonuclease - Apurinic Endonuclease - Endodeoxyribonuclease (Apurinic or Apyrimidinic)