Chlamydial DNA polymerase I can bypass lesions in vitro

Biochem Biophys Res Commun. 2006 Jul 7;345(3):1083-91. doi: 10.1016/j.bbrc.2006.05.021. Epub 2006 May 11.


We found that DNA polymerase I from Chlamydiophila pneumoniae AR39 (CpDNApolI) presents DNA-dependent DNA polymerase activity, but has no detectable 3' exonuclease activity. CpDNApolI-dependent DNA synthesis was performed using DNA templates carrying different lesions. DNAs containing 2'-deoxyuridine (dU), 2'-deoxyinosine (dI) or 2'-deoxy-8-oxo-guanosine (8-oxo-dG) served as templates as effectively as unmodified DNAs for CpDNApolI. Furthermore, the CpDNApolI could bypass natural apurinic/apyrimidinic sites (AP sites), deoxyribose (dR), and synthetic AP site tetrahydrofuran (THF). CpDNApolI could incorporate any dNMPs opposite both of dR and THF with the preference to dAMP-residue. CpDNApolI preferentially extended primer with 3'-dAMP opposite dR during DNA synthesis, however all four primers with various 3'-end nucleosides (dA, dT, dC, and dG) opposite THF could be extended by CpDNApolI. Efficiently bypassing of AP sites by CpDNApolI was hypothetically attributed to lack of 3' exonuclease activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Base Sequence
  • Binding Sites
  • Chlamydophila pneumoniae / enzymology*
  • Chlamydophila pneumoniae / genetics
  • DNA / chemistry
  • DNA Damage
  • DNA Polymerase I / metabolism
  • DNA Polymerase I / physiology*
  • DNA Primers / chemistry
  • Exonucleases / metabolism
  • Kinetics
  • Molecular Sequence Data
  • Recombinant Proteins / chemistry
  • Sequence Homology, Nucleic Acid


  • DNA Primers
  • Recombinant Proteins
  • DNA
  • DNA Polymerase I
  • Exonucleases
  • spleen exonuclease