Abstract
Cells need energy to survive. Ion-motive force (IMF) is one of the most important biological energy formats in bacterial cells. Essentially, the ion-motive force is the sum of electrical and chemical potential differences across the cell membrane. For bacteria, the ion-motive force is involved not only in ATP production but also in flagellar motility. The bacterial flagellar motor is driven either by proton or sodium ion. The ion-motive force measurement therefore requires the measurement of membrane potential, proton concentration, or sodium ion concentration. The bacterial flagellar motor is the most powerful molecular machine we have known so far. To understand the energetic condition of bacterial flagellar motors, together with single-motor torque measurement, methods for single-cell ion-motive force measurement have been developed. Here, we describe fluorescent approaches to measure the components of ion-motive force.
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Acknowledgments
I am grateful to Dr. Teuta Pilizota and Dr. Bai Fan for their assistance of single cell protonmotive force measurement. The work in my lab was supported by the Ministry of Science and Technology of the Republic of China under Contract No. MOST-103-2112-M-008-013-MY3.
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Lin, TS., Sun, YR., Lo, CJ. (2017). Measurements of Ion-Motive Force Across the Cell Membrane. In: Minamino, T., Namba, K. (eds) The Bacterial Flagellum. Methods in Molecular Biology, vol 1593. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-6927-2_15
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DOI: https://doi.org/10.1007/978-1-4939-6927-2_15
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