Volloch V Z, Rits S, Tumerman L
Nucleic Acids Res. 1979 Apr;6(4):1535-46. doi: 10.1093/nar/6.4.1535.
Nucleoside triphosphate phosphohydrolase (NTPase) activity was found in a preparation of E. Coli RNA polymerase. This enzymatic activity is capable of hydrolysing all four ribonucleoside triphosphates to the nucleoside diphosphates. However, during in vitro RNA synthesis directed by poly(dC) or poly(dT), only the non-complementary nucleoside triphosphate of the same heterocyclic class was hydrolysed. No incorporation of the non-complementary precursor into RNA could be detected in these experiments. When another RNA polymerase preparation, devoid of NTPase activity, was employed, there was no hydrolysis of any nucleoside triphosphate and significant incorporation of non-complemtary precursor into RNA was observed. These observations lead us to the conclusion that NTPase, acting in conjunction with RNA polymerase, has the function of correcting errors in transcription.
在大肠杆菌RNA聚合酶制剂中发现了核苷三磷酸磷酸水解酶（NTPase）活性。这种酶活性能够将所有四种核糖核苷三磷酸水解为核苷二磷酸。然而，在由聚（dC）或聚（dT）指导的体外RNA合成过程中，只有相同杂环类别的非互补核苷三磷酸被水解。在这些实验中未检测到非互补前体掺入RNA。当使用另一种没有NTPase活性的RNA聚合酶制剂时，没有任何核苷三磷酸被水解，并且观察到非互补前体大量掺入RNA。这些观察结果使我们得出结论，NTPase与RNA聚合酶共同作用，具有校正转录错误的功能。
