Excision of deoxyribose phosphate residues by DNA polymerase beta during DNA repair

Science. 1995 Aug 4;269(5224):699-702. doi: 10.1126/science.7624801.


Eukaryotic DNA polymerase beta (pol beta) can catalyze DNA synthesis during base excision DNA repair. It is shown here that pol beta also catalyzes release of 5'-terminal deoxyribose phosphate (dRP) residues from incised apurinic-apyrimidinic sites, which are common intermediate products in base excision repair. The catalytic domain for this activity resides within an amino-terminal 8-kilodalton fragment of pol beta, which comprises a distinct structural domain of the enzyme. Magnesium is required for the release of dRP from double-stranded DNA but not from a single-stranded oligonucleotide. Analysis of the released products indicates that the excision reaction occurs by beta-elimination rather than hydrolysis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Apurinic Acid
  • Base Sequence
  • Binding Sites
  • DNA / metabolism*
  • DNA Ligases / metabolism
  • DNA Polymerase I / metabolism*
  • DNA Repair*
  • DNA-(Apurinic or Apyrimidinic Site) Lyase
  • Deoxyribonuclease IV (Phage T4-Induced)
  • Edetic Acid / pharmacology
  • Hydrolysis
  • Lyases / metabolism
  • Molecular Sequence Data
  • Polynucleotides
  • Protein Structure, Tertiary
  • Rats
  • Ribosemonophosphates / metabolism*
  • Xenopus laevis


  • Polynucleotides
  • Ribosemonophosphates
  • apyrimidinic acid
  • Apurinic Acid
  • DNA
  • Edetic Acid
  • DNA Polymerase I
  • Deoxyribonuclease IV (Phage T4-Induced)
  • Lyases
  • DNA-(Apurinic or Apyrimidinic Site) Lyase
  • DNA Ligases