Inhibition of the wheat germ DNA polymerase A activity by the antiviral drug HPA-23.
Wheat germ DNA polymerase A, a gamma-like enzyme, recognized efficiently natural and synthetic RNA templates, resembling a retroviral reverse transcriptase (P. Laquel et al., Biochim Biophys Acta 1048 (1990): 139-148). Ammonium-21-tungsto-9-antimoniate (HPA-23), an antiviral drug, inhibited the DNA polymerase A activities, independently of the template primers used, i.e. activated DNA or polyriboadenylic acid oligodeoxythymidylate (poly(rA)-oligo(dT)). The inhibition observed in the poly(rA)-oligo(dT)-directed DNA polymerase A activity occurred in the presence of either Mg2+ or Mn2+ as divalent cation, and also with the 2'-fluoro analogue of poly(rA) as template. HPA-23 was a non-competitive inhibitor with respect to TTP, activated DNA, poly(rA)-oligo(dT), and poly(dAfl)-oligo(dT). A preincubation study showed a reversible HPA-23 binding to DNA polymerase A, in the presence of poly(rA)-oligo(dT) as the template primer.
Aoyama
H
H
Departamento de Bioquímica, I.B., Universidade Estadual de Campinas, S.P., Brasil.
Jucá
M B
MB
Castroviejo
M
M
Litvak
S
S
D000965:Antimony / Q000494:pharmacology*; D000998:Antiviral Agents / Q000494:pharmacology; D019384:Nucleic Acid Synthesis Inhibitors; D014908:Triticum / Q000196:embryology / Q000201:enzymology*; D017973:Tungsten Compounds / Q000494:pharmacology*
D000998:Antiviral Agents; D019384:Nucleic Acid Synthesis Inhibitors; D017973:Tungsten Compounds; C009613:ammonium tungsten antimonate hydroxide oxide; D000965:Antimony