Drescher B, Rössler H, Venker P, Wittmann W
Arch Geschwulstforsch. 1979;49(7):569-79.
An RNA-directed DNA polymerase was purified from bovine leukemia virus (BLV) by successive glycerol gradient centrifugation, column chromatography on phosphocellulose and gel filtration on Sephadex G-200. The purified DNA polymerase transcribes heteropolymeric regions of 30--40 S RNA isolated from avian myeloblastosis virus. The enzyme differs from other known DNA polymerases of mammalian type-C RNA tumor viruses by the following properties: 1. Its apparent molecular weight as estimated by velocity sedimentation data is 58,000 at 0.12 M KCl and 43,000 in the presence of 0.50 M KCl. 2. It has a Mg2+ optimum of 10 mM, and a Mn2+ optimum of 0.25 mM with (rA)n-(dT)10 as template. 3. At 50 mM KCl it is inhibited more than 70%, but it is not inhibited by phosphate ions at 2 mM. These properties confirm the peculiar position of BLV within the family Retraviridae.
通过连续甘油梯度离心、磷酸纤维素柱层析和葡聚糖凝胶G - 200凝胶过滤从牛白血病病毒（BLV）中纯化出一种RNA指导的DNA聚合酶。纯化的DNA聚合酶转录从禽成髓细胞瘤病毒分离的30 - 40 S RNA的杂聚区域。该酶与哺乳动物C型RNA肿瘤病毒的其他已知DNA聚合酶在以下特性上有所不同：1. 根据速度沉降数据估计，其在0.12 M KCl中的表观分子量为58,000，在0.50 M KCl存在下为43,000。2. 以(rA)n-(dT)10为模板时，其Mg2+的最适浓度为10 mM，Mn2+的最适浓度为0.25 mM。3. 在50 mM KCl时，它被抑制超过70%，但在2 mM时不受磷酸根离子抑制。这些特性证实了BLV在逆转录病毒科中的特殊地位。
