Polar location of the chemoreceptor complex in the Escherichia coli cell.
Polar location of the chemoreceptor complex in the Escherichia coli cell.
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DOI：
10.1126/science.8456299
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发表时间：
1993-03
期刊：
影响因子：
56.9
通讯作者：
J. Maddock;L. Shapiro
中科院分区：
文献类型：
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作者：
J. Maddock;L. Shapiro
真核细胞的功能呈现区室化，分布于各种膜结合的细胞器以及每个膜内的特定区域。对大肠杆菌中膜化学受体以及相关的细胞质趋化蛋白的空间分布进行了研究，将其作为细菌细胞中一种原型功能聚集体。细菌趋化性涉及一个磷酸中继系统，该系统由配体与膜受体结合引发，最终导致鞭毛旋转方向的改变。趋化信号的转导由内膜上的化学受体 - CheW - CheA三元复合物启动。这些三元复合物主要聚集在细胞两极。细胞质中的CheA和CheW蛋白在细胞两极的定位依赖于膜结合的化学受体。在缺乏CheA和CheW的菌株中，化学受体并不局限于细胞两极。在缺乏CheA时，化学受体 - CheW二元复合物呈极性定位，而在缺乏CheW的菌株中，化学受体 - CheA二元复合物并不局限于细胞两极。趋化蛋白的亚细胞定位可能反映了细菌细胞将细胞不同区域分隔用于特定功能的一种普遍机制。
The eukaryotic cell exhibits compartmentalization of functions to various membrane-bound organelles and to specific domains within each membrane. The spatial distribution of the membrane chemoreceptors and associated cytoplasmic chemotaxis proteins in Escherichia coli were examined as a prototypic functional aggregate in bacterial cells. Bacterial chemotaxis involves a phospho-relay system brought about by ligand association with a membrane receptor, culminating in a switch in the direction of flagellar rotation. The transduction of the chemotaxis signal is initiated by a chemoreceptor-CheW-CheA ternary complex at the inner membrane. These ternary complexes aggregate predominantly at the cell poles. Polar localization of the cytoplasmic CheA and CheW proteins is dependent on membrane-bound chemoreceptor. Chemoreceptors are not confined to the cell poles in strains lacking both CheA and CheW. The chemoreceptor-CheW binary complex is polarly localized in the absence of CheA, whereas the chemoreceptor-CheA binary complex is not confined to the cell poles in strains lacking CheW. The subcellular localization of the chemotaxis proteins may reflect a general mechanism by which the bacterial cell sequesters different regions of the cell for specialized functions.