Cryo-EM structures of the autoinhibited <em>E. coli</em> ATP synthase in three rotational states
- The Victor Chang Cardiac Research Institute, Australia
- Nanyang Technological University, Singapore
- University of Oxford, United Kingdom
Abstract
A molecular model that provides a framework for interpreting the wealth of functional information obtained on the <em>E. coli</em> F-ATP synthase has been generated using cryo-electron microscopy. Three different states that relate to rotation of the enzyme were observed, with the central stalk's ε subunit in an extended autoinhibitory conformation in all three states. The Fo motor comprises of seven transmembrane helices and a decameric c-ring and invaginations on either side of the membrane indicate the entry and exit channels for protons. The proton translocating subunit contains near parallel helices inclined by ~30º to the membrane, a feature now synonymous with rotary ATPases. For the first time in this rotary ATPase subtype, the peripheral stalk is resolved over its entire length of the complex, revealing the F1 attachment points and a coiled-coil that bifurcates towards the membrane with its helices separating to embrace subunit a from two sides.
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Author details
Alastair G Stewart
Funding
National Health and Medical Research Council (1004620)
- Daniela Stock
National Health and Medical Research Council (1109961)
- Daniela Stock
National Health and Medical Research Council (1090408)
- Alastair G Stewart
National Health and Medical Research Council (1022143)
- Daniela Stock
National Health and Medical Research Council (1047004)
- Daniela Stock
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Sobti et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Cryo-EM structures of the autoinhibited <em>E. coli</em> ATP synthase in three rotational states
eLife 5:e21598.
https://doi.org/10.7554/eLife.21598
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