Purification and Properties of the Major Apurinic/Apyrimidinic Endodeoxyribonuclease of Rat‐Liver Chromatin

Abstract

Two nucleases active on alkylated-depurinated DNA were extracted from rat liver chromatin with 1 M KCl. The major enzyme was purified to near homogeneity it has a MW of 12,500 (although some dimerization might occur) and needs Mg2+ or Mn2+ for activity. The endonuclease activity is specific for apurinic/apyrimidinic sites in DNA; the enzyme had no associated exonuclease activity.