Unique inhibitory effect of 1-(2'-deoxy-2'-fluoro-beta-L-arabinofuranosyl)-5-methyluracil 5'-triphosphate on Epstein-Barr virus and human DNA polymerases.
1-(2'-Deoxy-2'-fluoro-beta-L-arabinofuranosyl)-5-methyluracil (L-FMAU) was shown to have potent antiviral activity against Epstein-Barr virus (EBV) without any cellular toxicity at concentrations up to 200 microM (Yao et al., Biochem Pharmacol 51: 941-947, 1996). The 5'-triphosphate of L-FMAU was not a substrate for EBV or cellular DNA polymerases, but could inhibit the elongation reaction, 3'-to-5' exonuclease activity, and nucleotide turnover catalyzed by EBV DNA polymerase. DNA synthesis catalyzed by human DNA polymerases was inhibited to a lesser extent. The inhibition pattern of EBV DNA polymerase by L-FMAU-5'-triphosphate (L-FMAU-TP) was consistent with an uncompetitive mechanism when dNTP or template-primer were used as the variable substrates. The Ki values were 38+/-10 microM for the elongation reaction, and about 50+/-10 microM for both nucleotide exchange and 3'-to-5' exonuclease reactions, values that were 10-20 times less than that for GMP. L-FMAU-TP is the first nucleoside 5'-triphosphate shown to have such unique behavior toward DNA polymerases. EBV DNA polymerase could be one of the targets for the inhibitory effect of L-FMAU-TP on EBV replication.
Kukhanova
M
M
Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06510, USA.
Lin
Z Y
ZY
Yas'co
M
M
Cheng
Y C
YC
D000998:Antiviral Agents / Q000494:pharmacology*; D001085:Arabinofuranosylcytosine Triphosphate / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D002460:Cell Line; D004261:DNA Replication / Q000187:drug effects; D004268:DNA-Binding Proteins; D004259:DNA-Directed DNA Polymerase; D043211:Exodeoxyribonuclease V; D005090:Exodeoxyribonucleases / Q000037:antagonists & inhibitors; D005092:Exonucleases / Q000037:antagonists & inhibitors; D004854:Herpesvirus 4, Human / Q000187:drug effects*; D006801:Humans; D019384:Nucleic Acid Synthesis Inhibitors; D013379:Substrate Specificity; D014407:Tumor Cells, Cultured; D014764:Viral Proteins
D000998:Antiviral Agents; D004268:DNA-Binding Proteins; D019384:Nucleic Acid Synthesis Inhibitors; D014764:Viral Proteins; D001085:Arabinofuranosylcytosine Triphosphate; C047247:1-(2'-deoxy-2'-fluoro-beta-arabinofuranosyl)-5-methylcytosine triphosphate; C083202:BALF5 protein, Epstein-barr virus; D004259:DNA-Directed DNA Polymerase; D005090:Exodeoxyribonucleases; D005092:Exonucleases; D043211:Exodeoxyribonuclease V