Patent ID: 8129149

Claim:
A method for the rapid and sensitive measurement of endonuclease activity, comprising the steps of: (a) reacting endonuclease with a synthetic double-stranded oligonucleotide having first and second complementary strands, wherein said first strand is a substrate and comprises the sequence of SEQ ID: NO 1 and wherein said second strand is a template and comprises the sequence of SEQ ID: NO 2, wherein said first strand contains an apurinic/apyrimidinic site and said first and second strands have a terminal dideoxy cytosine to prevent DNA polymerase extension at its 3′ end, to thereby subject the apurinic/apyrimidinic site to endonuclease hydrolysis, said hydrolysis cleaving said first strand producing a 5′→3′ chain labeled A and a 5′→3′ chain labeled B and leaving the complementary 3′→5′ second strand uncut; (b) reacting the 5′→3′ chain labeled A with DNA polymerase to form a complementary strand to the uncut 3′→5′ second strand; and (c) subjecting the reaction product of step (b) to a polymerase chain reaction to detect the initial endonuclease activity.