Dobkin C, Mills D R, Kramer F R, Spiegelman S
Biochemistry. 1979 May 15;18(10):2038-44. doi: 10.1021/bi00577a030.
Replication complexes containing only one molecule of Q beta replicase and one strand of midivariant RNA (MDV-1 RNA) template were prepared by incubating the replicase with an excess of MDV-1 (-) RNA. In the presence of excess minus strands, these monoenzyme replication complexes were shown to synthesize essentially pure MDV-1 (+) RNA in both the first and second cycles of replication. When an equivalent concentration of mutant MDV-1 (-) RNA was added to this reaction before completion of the first cycle of replication, only wild-type MDV-1 (+) RNA was produced in the first cycle, but both mutant and wild-type MDV-1 (+) RNA were produced in the second cycle of replication. These results demonstrate that a monoenzyme complex is competent to synthesize RNA and, therefore, that a multienzyme replication complex is not a necessary intermediate of replication. The data also imply that after the completion of chain elongation, the product strand is released from the replication complex and that the template and the replicase then dissociate.
通过将复制酶与过量的MDV-1（-）RNA孵育，制备了仅包含一个Qβ复制酶分子和一条中变RNA（MDV-1 RNA）模板链的复制复合物。在存在过量负链的情况下，这些单酶复制复合物在复制的第一个和第二个循环中均显示出能合成基本上纯的MDV-1（+）RNA。当在第一个复制循环完成之前向该反应中加入等量浓度的突变型MDV-1（-）RNA时，在第一个循环中仅产生野生型MDV-1（+）RNA，但在第二个复制循环中同时产生突变型和野生型MDV-1（+）RNA。这些结果表明，单酶复合物有能力合成RNA，因此，多酶复制复合物不是复制的必要中间体。数据还暗示，在链延伸完成后，产物链从复制复合物中释放，然后模板和复制酶解离。
