Human cytomegalovirus. III. Virus-induced DNA polymerase
Human cytomegalovirus. III. Virus-induced DNA polymerase
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人类巨细胞病毒。
作者：
E. Huang
用人巨细胞病毒（CMV）感染WI-38人成纤维细胞导致宿主细胞DNA聚合酶合成的刺激和一种新的病毒特异性DNA聚合酶的诱导。这种巨细胞病毒诱导的DNA聚合酶被纯化，并通过DEAE-纤维素和磷酸纤维素柱层析从宿主细胞酶中分离。它可以通过色谱行为、模板引物特异性、沉降特性和最大活性所需的盐来与宿主细胞酶区分开。这种病毒诱导的酶具有9.2S的沉降系数，并且在病毒感染细胞的细胞核和细胞质中发现，但在未感染的细胞中不存在。该酶能有效地利用活化的小牛胸腺DNA、oly（dA）-oligo（dT）12-18和poly（dC）-oligo（dG）12-18作为模板引物，尤其是poly（dA）-oligo（dT）12-18，但不能利用poly（rA）-oligo（dT）12-18、poly（rC）-oligo（dG）12-18和oligo（dT）12-18。该酶需要Mg 2+才能获得最大活性，对苯甲酸羟基汞敏感，并且不是锌金属酶。另外，通过向反应混合物中加入0.06至0.12 M NaCl或0.03至0.06 M（NH 4）2SO 4，可以增强巨细胞病毒诱导的DNA聚合酶活性。
Infection of WI-38 human fibroblasts with human cytomegalovirus (CMV) led to the stimulation of host cell DNA polymerase synthesis and induction of a novel virus-specific DNA polymerase. This cytomegalovirus-induced DNA polymerase was purified and separated from host cell enzymes by DEAE-cellulose and phosphocellulose column chromatographies. It can be distinguished from host cell enzymes by chromatographic behavior, template primer specificity, sedimentation property, and the requirement of salt for maximal activity. This virus-induced enzyme has a sedimentation coefficient of 9.2S and is found in both the nuclei and cytoplasm of virus-infected cells, but not in uninfected cells. This enzyme could efficiently use activated calf-thymus DNA, oly(dA)-oligo(dT)12-18, and poly(dC)-oligo(dG)12-18 as template primers, especially poly(dA)-oligo(dT)12-18, but it could not use poly(rA)-oligo(dT)12-18, poly(rC)-oligo(dG)12-18, or oligo(dT)12-18. The enzyme requires Mg2+ for maximal activity, is sensitive to p-hydroxymercuribenzoate, and is not a zinc metalloenzyme. In addition, the cytomegalovirus-induced DNA polymerase activity can be enhanced by adding 0.06 to 0.12 M NaCl or 0.03 to 0.06 M (NH4)2SO4 to the reaction mixture.