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arXiv · 0903.0184

36 degree step size of proton-driven c-ring rotation in FoF1-ATP synthase

Monika G. Dueser·Nawid Zarrabi·Daniel J. Cipriano·Stefan Ernst·Gary D. Glick·Stanley D. Dunn·Michael Boersch
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Abstract

Synthesis of the biological "energy currency molecule" adenosine triphosphate ATP is accomplished by FoF1-ATP synthase. In the plasma membrane of Escherichia coli, proton-driven rotation of a ring of 10 c subunits in the Fo motor powers catalysis in the F1 motor. While F1 uses 120 degree stepping, Fo models predict a step-by-step rotation of c subunits 36 degree at a time, which is here demonstrated by single-molecule fluorescence resonance energy transfer.

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Monika G. Dueser, Nawid Zarrabi, Daniel J. Cipriano, Stefan Ernst, Gary D. Glick, Stanley D. Dunn, Michael Boersch. 2009-03-01. 36 degree step size of proton-driven c-ring rotation in FoF1-ATP synthase. https://arxiv.org/abs/0903.0184

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