Aoyama H, Jucá M B, Castroviejo M, Litvak S
Departamento de Bioquímica, I.B., Universidade Estadual de Campinas, S.P., Brasil.
Plant Mol Biol. 1993 Dec;23(5):1055-60. doi: 10.1007/BF00021819.
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.
小麦胚DNA聚合酶A是一种γ样酶，能有效识别天然和合成RNA模板，类似于逆转录病毒逆转录酶（P.拉克尔等人，《生物化学与生物物理学报》1048 (1990): 139 - 148）。抗病毒药物21 - 钨 - 9 - 锑酸铵（HPA - 23）抑制DNA聚合酶A的活性，与所使用的模板引物无关，即活化DNA或聚核糖腺苷酸寡聚脱氧胸苷酸（聚（rA）-寡聚（dT））。在聚（rA）-寡聚（dT）指导的DNA聚合酶A活性中观察到的抑制作用，在存在Mg2 +或Mn2 +作为二价阳离子时以及以聚（rA）的2'-氟类似物作为模板时都会发生。HPA - 23对TTP、活化DNA、聚（rA）-寡聚（dT）和聚（dAfl）-寡聚（dT）而言是一种非竞争性抑制剂。一项预孵育研究表明，在以聚（rA）-寡聚（dT）作为模板引物的情况下，HPA - 23与DNA聚合酶A的结合是可逆的。
