Measurements of the Ion Channel Activity of the Transmembrane Stator Complex in the Bacterial Flagellar Motor
Measurements of the Ion Channel Activity of the Transmembrane Stator Complex in the Bacterial Flagellar Motor
复制标题
细菌鞭毛运动跨膜定子复合体离子通道活性的测量
DOI：
10.1007/978-1-0716-3060-0_8
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发表时间：
2023
影响因子：
--
通讯作者：
Minamino Tohru
中科院分区：
文献类型：
--
作者：
Morimoto Yusuke V.;Minamino Tohru
细菌鞭毛由位于鞭毛基部的旋转马达驱动。定子单元复合物沿着电化学电势传导质子（H+）和钠离子（Na+）等阳离子穿过细胞质膜，并与转子相互作用产生旋转力。大肠杆菌和沙门氏菌具有H+型定子复合物，其作为跨膜H+通道，将H+流通过离子通道耦合到扭矩产生，而弧菌和一些芽孢杆菌物种具有Na+型定子复合物。在这一章中，我们描述了如何测量跨膜定子复合物的离子电导率过表达在E。colicells使用荧光指示剂。使用荧光分光光度计或显微镜对荧光指示剂进行强度测量，可以定量检测由于跨膜蛋白复合物的离子通道活性而引起的细胞内离子浓度的变化。
The bacterial flagellum is driven by a rotational motor located at the base of the flagellum. The stator unit complex conducts cations such as protons (H+) and sodium ions (Na+) along the electrochemical potential across the cytoplasmic membrane and interacts with the rotor to generate the rotational force.Escherichia coliandSalmonellahave the H+-type stator complex, which serves as a transmembrane H+channel that couples H+flow through an ion channel to torque generation whereasVibrioand someBacillusspecies have the Na+-type stator complex. In this chapter, we describe how to measure the ion conductivity of the transmembrane stator complex over-expressed inE. colicells using fluorescent indicators. Intensity measurements of fluorescent indicators using either a fluorescence spectrophotometer or microscope allow quantitative detection of changes in the intracellular ion concentrations due to the ion channel activity of the transmembrane protein complex.