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Characterization of the Bacillus subtilis motile system driven by an artificially created proton motive force.

S Matsuura·J I Shioi·Y Imae·S Iida
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Abstract

Transient swimming was induced in energy-depleted cells of Bacillus subtilis by an artificial proton motive force, which was created by valinomycin addition and a pH reduction. This system did not require any ions except protons in the medium. The size of the induced motility was strongly influenced by changes in the size of either the K+ diffusion potential or the pH gradient. A rough estimation indicated that a proton motive force higher than -100 mV was required for induction of translational swimming of the cell. Corresponding with the transient appearance of swimming, a rapid but transient efflux of K+ and influx of H+ were observed. With decreases in the rate of H+ influx, the amount of motility decreased. A rate of H+ influx higher than 0.2 mumol/s per ml of cell water gave translational swimming. These results suggest direct coupling of H+ influx to rotation of bacterial flagella.

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Adenosine TriphosphateBacillus subtilisCalciumHydrogenHydrogen-Ion ConcentrationMovementPotassiumProtonsValinomycinJournal Article

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S Matsuura, J I Shioi, Y Imae, S Iida. 1979. Characterization of the Bacillus subtilis motile system driven by an artificially created proton motive force.. https://doi.org/10.1128/jb.140.1.28-36.1979

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Glutamyl transfer ribonucleic acid synthetase of Escherichia coli. Study of the interactions with its substrates.

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