Kuzminov A, Schabtach E, Stahl F W
Institute of Molecular Biology, University of Oregon, Eugene 97403, USA.
J Mol Biol. 1997 Apr 25;268(1):1-7. doi: 10.1006/jmbi.1997.0955.
We studied theta-mode DNA replication in p15A-based Escherichia coli plasmids by analyzing their replication intermediates using a combination of neutral agarose 2D gel electrophoresis and electron microscopy. Our analysis: (1) confirms the original assignment of various features of the 2D gel pattern; (2) shows that while one replication fork progresses around the plasmid DNA, the other is immobile, as if the replication were unidirectional; and (3) reveals that termination often occurs at a location away from the replication origin, suggesting that the replication of our plasmids is, in fact, bidirectional, the two forks being active at different times.
我们通过结合中性琼脂糖二维凝胶电泳和电子显微镜分析其复制中间体，研究了基于p15A的大肠杆菌质粒中的θ模式DNA复制。我们的分析：（1）证实了二维凝胶图谱各种特征的最初归属；（2）表明当一个复制叉围绕质粒DNA前进时，另一个是静止的，就好像复制是单向的；（3）揭示了终止通常发生在远离复制起点的位置，这表明我们的质粒复制实际上是双向的，两个复制叉在不同时间活跃。
