SimA, a nucleoid-associated, FtsZ binding protein required for blocking septal ring assembly over chromosomes in E coli
SimA, a nucleoid-associated, FtsZ binding protein required for blocking septal ring assembly over chromosomes in E coli
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DOI：
10.1016/j.molcel.2005.04.012
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发表时间：
2005-05-27
期刊：
影响因子：
16
通讯作者：
de Boer, PAJ
中科院分区：
文献类型：
--
作者：
Bernhardt, TG;de Boer, PAJ
大肠杆菌的细胞分裂始于微管蛋白样FtsZ蛋白在细胞膜下组装成环状结构。Z环组装的空间控制是通过两个部分冗余的负调控系统来实现的，Min系统和类核闭塞（NO），它们合作将分裂位点定位在中间细胞。相反，充分研究的Min系统，几乎没有什么是已知的Z环组装是如何被阻止在附近的类核，以影响NO。推理Min功能可能成为必不可少的细胞受损的NO，我们筛选的突变合成致命的缺陷Min系统（SLM突变体）。通过这种方法，我们确定了SlmA（Ttk）是大肠杆菌中的第一个NO因子。杆菌我们结合遗传学，细胞学和生化结果表明，SLmA是一种DNA相关的分裂抑制剂，直接参与防止Z环组装在周围的类核膜的部分。
Cell division in Escherichia coli begins with assembly of the tubulin-like FtsZ protein into a ring structure just underneath the cell membrane. Spatial control over Z ring assembly is achieved by two partially redundant negative regulatory systems, the Min system and nucleoid occlusion (NO), which cooperate to position the division site at midcell. In contrast to the well-studied Min system, almost nothing is known about how Z ring assembly is blocked in the vicinity of nucleoids to effect NO. Reasoning that Min function might become essential in cells impaired for NO, we screened for mutations synthetically lethal with a defective Min system (slm mutants). By using this approach, we identified SlmA (Ttk) as the first NO factor in E. coli. Our combined genetic, cytological, and biochemical results suggest that SlmA is a DNA-associated division inhibitor that is directly involved in preventing Z ring assembly on portions of the membrane surrounding the nucleoid.