A 70-kDa chloroplast DNA polymerase from pea ( Pisum sativum) that shows high processivity and displays moderate fidelity

Mol Genet Genomics. 2002 Mar;267(1):45-56. doi: 10.1007/s00438-001-0631-8. Epub 2002 Jan 26.


A 70-kDa chloroplast (ct) DNA polymerase from pea has been purified to apparent homogeneity. The ct DNA polymerase was insensitive to dideoxynucleotides (d(2) NTP) but showed high sensitivity to phosphonoacetic acid. The enzyme lacked any detectable 5'-->3' exonuclease activity but showed 3'-->5' exonuclease activity. The polymerase displayed high processivity (3 kb) and moderate fidelity, which may be sufficient for the faithful replication of the 140-kb pea ct genome. A 43-kDa accessory protein increased the polymerization rate but did not affect the rate of mis-incorporation in vitro, thus indicating that the domains for polymerisation and proof reading may be spatially separate.

MeSH terms

  • Base Sequence
  • DNA Replication
  • DNA, Plant
  • DNA-Directed DNA Polymerase / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme Inhibitors / pharmacology
  • Exodeoxyribonuclease V
  • Exodeoxyribonucleases / metabolism
  • Molecular Sequence Data
  • Nucleic Acid Synthesis Inhibitors
  • Peas / enzymology*
  • Peas / genetics


  • DNA, Plant
  • Enzyme Inhibitors
  • Nucleic Acid Synthesis Inhibitors
  • DNA-Directed DNA Polymerase
  • Exodeoxyribonucleases
  • Exodeoxyribonuclease V