2',3'-dideoxyguanosine 5'-triphosphate (ddGTP) was found to be an efficient substrate for DNA polymerase beta when activated DNA was used as the template.primer. Under the optimized reaction conditions with activated DNA, the rate of the incorporation of ddGTP into DNA was almost equal to that of the corresponding normal substrate dGTP. The Km value for ddGTP (1.8 microM) was smaller than that for dGTP (7.8 microM). In contrast, ddGTP was not utilized as a substrate for DNA polymerase gamma with any of the activated DNA and (dC)n.(dG)12-18 as the template primer. Other DNA polymerases such as DNA polymerase alpha, E coli DNA polymerase I and retroviral reverse transcriptase could poorly utilize ddGTP as a substrate. Some of the kinetic properties of DNA polymerase beta revealed toward ddGTP are also described. Since DNA polymerase beta plays a role in DNA repair, the present results predict possible appearance of cytotoxicity or clinical side effect(s) of 2',3'-dideoxyguanosine (ddG), known as a potent inhibitor of human immunodeficiency virus, when ddG is administered to the patients with acquired immune deficiency syndrome (AIDS) or AIDS-related complex.

中文翻译：

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2'，3'-二脱氧鸟苷5'-三磷酸酯作为各种DNA聚合酶底物的差异利用。

当将活化的DNA用作模板引物时，发现2'，3'-二脱氧鸟苷5'-三磷酸（ddGTP）是DNA聚合酶β的有效底物。在优化的活化DNA反应条件下，ddGTP掺入DNA的速率几乎等于相应正常底物dGTP的速率。ddGTP（1.8 microM）的Km值小于dGTP（7.8 microM）的Km值。相反，ddGTP未被用作DNA聚合酶γ的底物，而任何活化的DNA和（dC）n。（dG）12-18作为模板引物。其他DNA聚合酶（例如DNA聚合酶α，大肠杆菌DNA聚合酶I和逆转录病毒逆转录酶）可能无法充分利用ddGTP作为底物。还描述了向ddGTP揭示的DNA聚合酶β的一些动力学性质。