Comparison of DNA polymerase activities between recombinant feline immunodeficiency and leukemia virus reverse transcriptases

Virology. 2005 Apr 25;335(1):106-21. doi: 10.1016/j.virol.2005.02.010.


In this study, we present enzymatic differences found between recombinant RTs derived from feline leukemia virus and feline immunodeficiency virus. Firstly, FIV RT showed low steady state K(m) values for dNTPs compared to FeLV RT. Consistent with this, FIV RT synthesized DNA more efficiently than FeLV RT at low dNTP concentrations. We observed similar concentration-dependent activity differences between other lentiviral (HIV-1 and SIV) and non-lentiviral (MuLV and AMV) RTs. Second, FeLV RT showed less efficient misincorporation with biased dNTP pools and mismatch primer extension capabilities, compared to FIV RT. In M13mp2 lacZalpha forward mutation assays, FeLV RT displayed approximately 11-fold higher fidelity than FIV RT. Finally, FeLV RT was less sensitive to 3TCTP and ddATP than FIV RT. This study represents the comprehensive enzymatic characterization of RTs from a lentivirus and a non-lentivirus retrovirus from the same host species. The data presented here support enzymatic divergences seen among retroviral RTs.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cats
  • DNA-Directed DNA Polymerase / metabolism*
  • Deoxyribonucleotides / metabolism
  • Immunodeficiency Virus, Feline / enzymology*
  • Immunodeficiency Virus, Feline / genetics
  • Kinetics
  • Leukemia Virus, Feline / enzymology*
  • Leukemia Virus, Feline / genetics
  • Molecular Sequence Data
  • RNA-Directed DNA Polymerase / drug effects
  • RNA-Directed DNA Polymerase / genetics
  • RNA-Directed DNA Polymerase / metabolism*
  • Recombination, Genetic*
  • Reverse Transcriptase Inhibitors / pharmacology


  • Deoxyribonucleotides
  • Reverse Transcriptase Inhibitors
  • RNA-Directed DNA Polymerase
  • DNA-Directed DNA Polymerase