Fidelity analysis of HIV-1 reverse transcriptase mutants with an altered amino-acid sequence at residues Leu74, Glu89, Tyr115, Tyr183 and Met184

Eur J Biochem. 2000 May;267(9):2658-65. doi: 10.1046/j.1432-1327.2000.01272.x.


Substitution of particular residues postulated to have a role in active site architecture can alter the overall fidelity of DNA polymerization by HIV-1. The effects of this kind of substitution were determined in a lacZ-based assay using HIV-1 reverse transcriptase with specifically mutated residues. We found that the reported higher fidelity of nucleotide incorporation by the Met184-->Val and Glu89-->Gly mutant reverse transcriptases (RTs) was not reflected in a substantial increase in the overall fidelity for these RT mutants. For the 3TC-resistant Met184-->Val RT mutant an almost wild-type level of overall mutation frequency was observed, while the foscarnet-resistant RTs harbouring the Glu89-->Gly mutation showed only a twofold decrease in mutation frequency. The Tyr183-->Phe mutant RT displayed a slightly lower fidelity than wild-type RT. Conversely, the ddI-resistant RT mutant containing the Leu74-->Val mutation showed a 3.5-fold higher fidelity compared to the wild-type enzyme. Finally, the Tyr115-->Ala substitution rendered the enzyme substantially more error-prone for DNA polymerization. These results correlate with three-dimensional structural studies of the polymerase active site and confirm the postulated impact of the Leu74, Tyr183 and Tyr115 RT residues on the overall fidelity of DNA polymerization by HIV-1 RT.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution
  • Amino Acids / chemistry*
  • Amino Acids / genetics
  • Base Sequence
  • Biopolymers
  • HIV Reverse Transcriptase / chemistry
  • HIV Reverse Transcriptase / genetics
  • HIV Reverse Transcriptase / metabolism*
  • Models, Molecular
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Sequence Homology, Nucleic Acid


  • Amino Acids
  • Biopolymers
  • HIV Reverse Transcriptase