Catalysis of the cleavage of an AP site 3' of the baseless site by a beta-lyase mechanism, leaving an unsaturated aldehyde, termed a 3'-(4-hydroxy-5-phospho-2-pentenal) residue, and a 5'-phosphate.
Comment:
Note that this term is does not have parentage in the 'nuclease activity' branch of the ontology because both GO and the Enzyme Commission define nuclease activity as a type of hydrolysis. Class II AP endonuclease is a nuclease, but not Class I, III and IV.
Synonyms:
exact_synonym:
AP site-DNA 5'-phosphomonoester-lyase activity; DNA-(apurinic or apyrimidinic site) 5'-phosphomonoester-lyase activity; DNA-(apurinic or apyrimidinic site) lyase activity; class I DNA-(apurinic or apyrimidinic site) lyase activity
related_synonym:
AP endonuclease class I activity; AP lyase activity