HIV-1 reverse transcriptase: inhibition by 2',5'-oligoadenylates

Biochemistry. 1993 Nov 16;32(45):12112-8. doi: 10.1021/bi00096a023.


2',5'-Oligoadenylates (2-5A) and derivatives are noncompetitive inhibitors of primer/HIV-1 reverse transcriptase complex formation. The mechanism and specificity of this inhibitory action of 2-5A and 2-5A derivatives have been evaluated with 2-5A molecules modified in ribosyl moiety, chain length, extent of 5'-phosphorylation, and 2',5'-phosphodiester linkage. UV covalent cross-linking of preformed complexes of p66/p66 homodimer or p66/p51 heterodimer recombinant HIV-1 reverse transcriptase and the primer analog pd(T)16 allowed analysis of the initial step in HIV-1 reverse transcriptase-catalyzed DNA synthesis. Utilizing this primer binding assay, it is demonstrated that 2-5A and 2-5A derivatives inhibit the binding of pd(T)16 to HIV-1 reverse transcriptase. This inhibition is specific for the 2',5'-internucleotide linkage in that the corresponding 3',5'-adenylate derivatives do not exhibit inhibitory activity. Enhanced inhibitory properties were observed following modifications of the 2-5A molecule which result in an increase in hydrophobicity. Replacement of the D-ribosyl moiety of 2-5A with the 3'-deoxyribosyl moiety increased the inhibition of primer/HIV-1 reverse transcriptase complex formation 15-20%. 2',5'-Phosphorothioate substitution yielded the most effective inhibitors, with Ki's of 7-13 microM. In all cases, inhibition of primer/HIV-1 reverse transcriptase complex formation showed a preference for the 5'-triphosphate moiety. Nonphosphorylated derivatives were not inhibitory; 5'-monophosphate derivatives exhibited little or no inhibition. The inhibition of primer binding to HIV-1 reverse transcriptase correlated well with the inhibition of DNA-directed DNA synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

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

MeSH terms

  • Adenine Nucleotides / pharmacology*
  • Antiviral Agents / pharmacology*
  • DNA / biosynthesis
  • DNA / drug effects
  • HIV Reverse Transcriptase
  • HIV-1 / enzymology*
  • Oligoribonucleotides / pharmacology*
  • Phosphorylation
  • Photochemistry
  • Reverse Transcriptase Inhibitors*
  • Thymidine / metabolism


  • Adenine Nucleotides
  • Antiviral Agents
  • Oligoribonucleotides
  • Reverse Transcriptase Inhibitors
  • 2',5'-oligoadenylate
  • DNA
  • HIV Reverse Transcriptase
  • Thymidine