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Studying mechanosensitive ion channels with an automated patch clamp

Abstract

Patch clamp electrophysiology is the main technique to study mechanosensitive ion channels (MSCs), however, conventional patch clamping is laborious and success and output depends on the skills of the operator. Even though automated patch systems solve these problems for other ion channels, they could not be applied to MSCs. Here, we report on activation and single channel analysis of a bacterial mechanosensitive ion channel using an automated patch clamp system. With the automated system, we could patch not only giant unilamellar liposomes but also giant Escherichia coli (E. coli) spheroplasts. The tension sensitivity and channel kinetics data obtained in the automated system were in good agreement with that obtained from the conventional patch clamp. The findings will pave the way to high throughput fundamental and drug screening studies on mechanosensitive ion channels.

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Acknowledgments

This work was financially supported by a European Research Council-Ideas Program Starting Grant 208814 to A.K. and, in part, by the SME innovation program “ZIM” of the German Federal Ministry of Economics and Technology (BMWi).

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Correspondence to Armağan Koçer.

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M. Barthmes and M. D. F. Jose contributed equally.

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Barthmes, M., Jose, M.D.F., Birkner, J.P. et al. Studying mechanosensitive ion channels with an automated patch clamp. Eur Biophys J 43, 97–104 (2014). https://doi.org/10.1007/s00249-014-0944-2

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Keywords

  • Patch clamp electrophysiology
  • Automated patch clamp
  • Mechanosensitive channel of large conductance
  • Spheroplast
  • Giant unilamellar vesicles