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A patch-clamp study of Bacillus subtilis.

I Szabó·V Petronilli·M Zoratti
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Abstract

In patch-clamp experiments on giant protoplasts of the Gram-positive bacterium Bacillus subtilis, membrane stretch resulted in an initial transient collapse of the membrane resistance, after which stretch-activated, voltage modulated, high-conductance channels could be observed. The channel open probability increased exponentially with applied suction and positive voltage, as a result of variations of both the mean open and the mean closed times. The substate structure and other characteristics of the electrical activity suggested the presence of a family of pores exhibiting cooperative behavior. A role in osmotic protection is suggested. In the intact bacteria, the pores may be part of an unidentified envelope apparatus, having other functions as well.

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Bacillus subtilisCell MembraneIon Channel GatingIon ChannelsLipid BilayersJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

I Szabó, V Petronilli, M Zoratti. 1992-11-23. A patch-clamp study of Bacillus subtilis.. https://doi.org/10.1016/0005-2736(92)90250-p

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