Huisman O, D'Ari R
Nature. 1981 Apr 30;290(5809):797-9. doi: 10.1038/290797a0.
Cell division is a tightly regulated periodic process. In steady-state cultures of Enterobacteriaceae, division takes place at a well defined cell mass and is strictly coordinated with DNA replication. In wild-type Escherichia coli the formation of cells lacking DNA is very rare, and interruptions of DNA replication arrest cell division. The molecular bases of this replication-division coupling have been elusive but several models have been proposed. It has been suggested, for example, that the termination of a round of DNA replication may trigger a key event required for cell division. A quite different model postulates the existence of a division inhibitor which prevents untimely division and whose synthesis is induced to high levels when DNA replication is perturbed. The work reported here establishes the existence of the latter type of replication-division coupling in E. coli, and shows that the sfiA gene product is an inducible component of this division inhibition mechanism which is synthesized at high levels after perturbations of DNA replication.
细胞分裂是一个受到严格调控的周期性过程。在肠杆菌科的稳态培养物中，细胞分裂发生在明确界定的细胞质量时，并与DNA复制严格协调。在野生型大肠杆菌中，缺乏DNA的细胞形成非常罕见，DNA复制的中断会阻止细胞分裂。这种复制-分裂偶联的分子基础一直难以捉摸，但已经提出了几种模型。例如，有人提出一轮DNA复制的终止可能会触发细胞分裂所需的关键事件。一个截然不同的模型假定存在一种分裂抑制剂，它可防止过早分裂，并且当DNA复制受到干扰时其合成会被诱导到高水平。此处报道的工作证实了大肠杆菌中存在后一种类型的复制-分裂偶联，并表明sfiA基因产物是这种分裂抑制机制的可诱导成分，在DNA复制受到干扰后会高水平合成。
