Brishammar S, Juntti N
Biochim Biophys Acta. 1975 Apr 2;383(4):351-8. doi: 10.1016/0005-2787(75)90304-4.
A poly(U) polymerizing enzyme has been found in healthy and tobacco mosaic virus-infected tobacco leaves and has been partially purified by affinity chromatography on a gel prepared from agarose with chemically coupled RNA. The enzyme is stimulated by Mn-2+ and dependent on a polynucleotide, preferentially poly(A). The synthesis proceeds optimally at pH 7.6 and 25 degrees C. The enzyme is highly specific for UTP and is inhibited by other ribonucleoside triphosphates. The product was partly sensitive to pancreatic ribonuclease. The synthetic reaction is inhibited in the presence of pyrophosphate but insensitive to 10 mM orthophosphate and high levels of cordycepin, rifampicin and actinomycin D. A molecular weight of about 40,000 has been estimated by sucrose gradient analysis and partition cell ultracentrifugation.
在健康的和感染烟草花叶病毒的烟草叶片中发现了一种聚（U）聚合酶，并且通过在由化学偶联RNA的琼脂糖制备的凝胶上进行亲和层析将其部分纯化。该酶受Mn-2+刺激并依赖于多核苷酸，优先为聚（A）。合成反应在pH 7.6和25℃时最佳进行。该酶对UTP具有高度特异性，并被其他核糖核苷三磷酸抑制。产物对胰核糖核酸酶部分敏感。合成反应在焦磷酸存在下受到抑制，但对10 mM正磷酸盐以及高水平的虫草素、利福平和平阳霉素不敏感。通过蔗糖梯度分析和分配池超速离心估计分子量约为40,000。
