CedA is a novel Escherichia coli protein that activates the cell division inhibited by chromosomal DNA over-replication
CedA is a novel Escherichia coli protein that activates the cell division inhibited by chromosomal DNA over-replication
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DOI：
10.1046/j.1365-2958.1997.5941967.x
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发表时间：
1997-11-01
影响因子：
3.6
通讯作者：
Sekimizu, K
中科院分区：
文献类型：
--
作者：
Katayama, T;Takata, M;Sekimizu, K
我们在大肠杆菌中分离并鉴定了一个与细胞分裂调控相关的新基因，在30℃时，dna Acos突变体会导致染色体的过度复制，并抑制克隆形成。我们发现，在这种温度下，dna Acos细胞形成细丝；因此，隔膜的形成受到抑制，这种抑制不依赖于隔膜形成蛋白FtsZ的抑制剂SFIA。为了确定参与这一抑制途径的因素，我们分离了dna Acos突变体的冷敏感表型的七个多拷贝抑制子。其中一个是以前未知的基因，我们将其命名为CEDA，该基因编码一个12 kDa的蛋白，位于大肠杆菌基因组图谱上的38.9分钟，CEDA基因的多拷贝供应给dna Acos细胞不能抑制染色体的过度复制，但确实刺激了宿主细胞的分裂，结果是染色体拷贝数异常增加的细胞生长，因此，CEDA基因的表达水平对于抑制30℃下dna Acos突变体的细胞分裂似乎是重要的。我们认为染色体的过度复制激活了一条抑制细胞分裂的途径，CEDA基因调节这种分裂控制。在Dna A(+)背景下，CEDA似乎也影响细胞分裂。
We isolated and characterized a new gene related to the control of cell division regulation in Escherichia coli, At 30 degrees C, the dnaAcos mutant causes over-replication of the chromosome, and colony formation is inhibited. We found that, at this temperature, the dnaAcos cells form filaments; therefore, septum formation is inhibited, This inhibition was independent of SfiA, an inhibitor of the septum-forming protein, FtsZ. To identify factors involved in this pathway of inhibition, we isolated seven multicopy suppressors for the cold-sensitive phenotype of the dnaAcos mutant. One of these proved to be a previously unknown gene, which we named cedA, This gene encoded a 12 kDa protein and resided at 38.9 min on the E. coli genome map, A multicopy supply of the cedA gene to the dnaAcos cells did not repress over-replication of the chromosome but did stimulate cell division of the host, the result being growth of cells with an abnormally elevated chromosomal copy number, Therefore, the expression level of the cedA gene seems to be important for inhibiting cell division of the dnaAcos mutant at 30 degrees C. We propose that overreplication of the chromosome activates a pathway for inhibiting cell division and that the cedA gene modulates this division control, In the dnaA(+) background, cedA also seems to affect cell division.