Thermo Scientific Endonuclease IV (Endo IV) recognizes apurinic/apyrimidinic (AP) sites of dsDNA and cleaves the phosphodiester bond 5' to the lesion generating a hydroxyl group at the 3'-terminus (see Figure 1 in Supporting Data). The enzyme can also act as a 3'-diesterase that is able to release 3'-phosphoglycolate or 3'-phosphate from the damaged ends of dsDNA. Endo IV possesses also a 3'→5' exonuclease activity. Its progression on substrates is sensitive to ionic strength, metal ions, EDTA, and reducing conditions. Substrates with 3'-recessed ends are preferred substrates for the 3'→5' exonuclease activity.

The enzyme has no requirement for Mg²⁺ and is fully active in the presence of EDTA in moderate concentrations.

Applications

• Studies of DNA damage and repair
• Single cell electrophoresis (comet assay)
• Antitumor drug research
• DNA structure research
• SNP analysis