Excision of Apurinic Sites from DNA with Enzymes Isolated from Rat‐Liver Chromatin

Abstract
Apurinic sites were excised from phage .vphi.X174 RF [replicative form] DNA with 2 enzymes isolated from rat liver chromatin: an apurinic/apyrimidinic endodeoxyribonuclease (EC 3.1.25.2) and a 5''-3''-exonuclease; the resulting gap was filled with DNA polymerase .beta. (EC 2.7.7.7) also prepared from rat liver chromatin and the repair was fully terminated with T4 DNA ligase (EC 6.5.1.1).