Ono K, Nakane H, De Clercq E
Laboratory of Viral Oncology, Aichi Cancer Center Research Institute, Nagoya, Japan.
Eur J Biochem. 1990 Jul 5;190(3):463-7. doi: 10.1111/j.1432-1033.1990.tb15596.x.
(E)-5-(2-Bromovinyl)-2'-deoxyuridine 5'-triphosphate (BrVdUTP) and (E)-5-(2-bromovinyl)-1-beta-D-arabinofuranosyluracil 5'-triphosphate (BrVarafUTP), which are known as specific inhibitors of herpes simplex viral (type 1 and 2) DNA polymerase, were found to be strong inhibitors of DNA polymerase gamma from human KB and murine myeloma cells. In fact BrVdUTP and BrVarafUTP were found to be stronger inhibitors of DNA polymerase gamma than of other DNA polymerases having viral (herpes simplex virus or retrovirus) origin or cellular (eukaryotic alpha and beta, or prokaryotic) origin. The mode of inhibition of DNA polymerase gamma by BrVdUTP and BrVarafUTP was competitive with respect to dTTP, the normal substrate. Whereas BrVdUTP was an efficient substrate for DNA polymerase gamma and other DNA polymerases that were examined, BrVarafUTP failed to serve as a substrate for DNA synthesis. Ki values for BrVdUTP (40 nM) and BrVarafUTP (7 nM) with DNA polymerase gamma, as determined with (rA)n.(dT) as the template.primer, were much smaller than the Km values for dTTP (0.16 microM and 0.71 microM for murine and human DNA polymerase gamma, respectively). Thus, the affinity of BrVdUTP or BrVarafUTP for DNA polymerase gamma was much stronger than that of dTTP.
（E）-5-（2-溴乙烯基）-2'-脱氧尿苷5'-三磷酸（BrVdUTP）和（E）-5-（2-溴乙烯基）-1-β-D-阿拉伯呋喃糖基尿嘧啶5'-三磷酸（BrVarafUTP），已知为单纯疱疹病毒（1型和2型）DNA聚合酶的特异性抑制剂，被发现是人类KB细胞和鼠骨髓瘤细胞中DNA聚合酶γ的强抑制剂。事实上，发现BrVdUTP和BrVarafUTP对DNA聚合酶γ的抑制作用比对其他具有病毒（单纯疱疹病毒或逆转录病毒）起源或细胞（真核α和β，或原核）起源的DNA聚合酶更强。BrVdUTP和BrVarafUTP对DNA聚合酶γ的抑制模式相对于正常底物dTTP是竞争性的。虽然BrVdUTP是DNA聚合酶γ和其他所检测的DNA聚合酶的有效底物，但BrVarafUTP不能作为DNA合成的底物。以（rA）n·（dT）作为模板引物测定的BrVdUTP（40 nM）和BrVarafUTP（7 nM）对DNA聚合酶γ的Ki值，比dTTP的Km值（鼠和人DNA聚合酶γ分别为0.16 μM和0.71 μM）小得多。因此，BrVdUTP或BrVarafUTP对DNA聚合酶γ的亲和力比dTTP强得多。
