几种药物对小鼠腹水癌细胞中一种DNA多聚酶及酶与模板复合体的作用

在小鼠艾氏腹水癌细胞中存在着一种DNA多聚酶及其与DNA模板的复合体。以不同药物对部分纯化的酶蛋白和复合体进行抑制实验,发现Aphidicolin、溴化乙锭、新生霉素和肝素均不同程度地抑制复合体和酶蛋白的活性;但酶蛋白和复合体对双脱氧胸苷三磷酸(ddTTP)不敏感。另外还发现复合体较酶蛋白对抑制剂有较强的抗性。

EFFECT OF INHIBITORS ON A DNA POLYMERASE AND ITS COMPLEX WITH DNA TEMPLATE FROM MOUSE EHRLICH ASCITES CARCINOMA

A DNA polymerase and its complex with endogenous DNA fragments were found in mouse Ehrlicll ascites carcinoma. The partially purified enzyme and complex were tested with several inhibitors of DNA polymerase. We found that aphidicolin ( a specific inhibitor to DNA polymerase α ) , novobiocin, ethidium bromide and heparin could all inhibit the enzyme and the complex, but the enzyme and the complex were not sensitive to ddTTP which can strongly inhibit DNA polymerase β and γ from eucaryotes. We also found that the complex differs from the enzyme protein in that the complex needs more of the inhibitors to reach the same Ievel of inhibition as the enzyme protein does.