ROLE OF CHEW PROTEIN IN COUPLING MEMBRANE-RECEPTORS TO THE INTRACELLULAR SIGNALING SYSTEM OF BACTERIAL CHEMOTAXIS
ROLE OF CHEW PROTEIN IN COUPLING MEMBRANE-RECEPTORS TO THE INTRACELLULAR SIGNALING SYSTEM OF BACTERIAL CHEMOTAXIS
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DOI：
10.1073/pnas.86.22.8703
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发表时间：
1989-11-01
影响因子：
11.1
通讯作者：
PARKINSON, JS
中科院分区：
文献类型：
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作者：
LIU, JD;PARKINSON, JS
大肠杆菌的趋化行为是由膜相关的化学感受器介导的，该感受器通过细胞内信号系统将感觉信号传递给鞭毛马达，这似乎涉及蛋白质磷酸化级联。本研究关注细胞质蛋白CheW在细胞内信号系统中偶联甲基接受趋化蛋白（MCPs）的作用，MCPs是一类主要的膜受体。在一系列具有不同组合和相对量的CheW、MCPs和其他信号成分的菌株中，研究了稳态鞭毛旋转行为。在正常表达水平下，CheW刺激顺时针旋转，受体似乎增强了这种刺激作用。在高表达水平下，MCPs抑制顺时针旋转，而CheW似乎增强了这种抑制作用。由于过表达的CheW或MCP分子与缺乏它们具有相同的行为效应，化学感受器可能使用CheW来调节两种不同的信号，一种刺激，一种抑制细胞内磷酸化级联反应。
Chemotactic behavior in Escherichia coli is mediated by membrane-associated chemoreceptors that transmit sensory signals to the flagellar motors through an intracellular signaling system, which appears to involve a protein phosphorylation cascade. This study concerns the role of CheW, a cytoplasmic protein in coupling methyl-accepting chemotaxis proteins (MCPs), the major class of membrane receptor, to the intracellular signaling system. Steady-state flagellar rotation behavior was examined in a series of strains with different combinations and relative amounts of CheW, MCPs, and other signaling components. At normal expression levels, CheW stimulated clockwise rotation, and receptors appeared to enhance this stimulatory effect. At high expression levels, MCPs inhibited clockwise rotation, and CheW appeared to augment this inhibitory effect. Since overexpression of CheW or MCP molecules had the same behavioral effect as their absence, chemoreceptors probably use CheW to modulate two distinct signals, one that stimulates and one that inhibits the intracellular phosphorylation cascade.