Cryo-EM reveals distinct conformations of E. coli ATP synthase on exposure to ATP
- The Victor Chang Cardiac Research Institute, Australia
- University of Oxford, United Kingdom
- The University of Wollongong, Australia
- SUNY Upstate Medical University, United States
Abstract
ATP synthase produces the majority of cellular energy in most cells. We have previously reported cryo-EM maps of autoinhibited E. coli ATP synthase imaged without addition of nucleotide (Sobti et al. 2016), indicating that the subunit ε engages the α, β and γ subunits to lock the enzyme and prevent functional rotation. Here we present multiple cryo-EM reconstructions of the enzyme frozen after the addition of MgATP to identify the changes that occur when this ε inhibition is removed. The maps generated show that, after exposure to MgATP, E. coli ATP synthase adopts a different conformation with a catalytic subunit changing conformation substantially and the ε C-terminal domain transitioning via an intermediate 'half-up' state to a condensed 'down' state. This work provides direct evidence for unique conformational states that occur in E. coli ATP synthase when ATP binding prevents the ε C-terminal domain from entering the inhibitory 'up' state.
Data availability
Cryo-EM maps have been deposited to the EMDB. Codes: EMD-9345, EMD-9346 and EMD-9348.
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E. coli ATP synthase after incubation with ATP - State AElectron Microscopy Data Bank, EMD-9345.
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E. coli ATP synthase after incubation with ATP - State BElectron Microscopy Data Bank, EMD-9346.
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E. coli ATP synthase after incubation with ATP - State CElectron Microscopy Data Bank, EMD-9348.
Article and author information
Author details
Alastair G Stewart
Funding
National Health and Medical Research Council (APP1159347)
- Alastair G Stewart
National Health and Medical Research Council (APP1146403)
- Meghna Sobti
- Alastair G Stewart
Australian Research Council (DE160100608)
- Mary Christie
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, 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 reveals distinct conformations of E. coli ATP synthase on exposure to ATP
eLife 8:e43864.
https://doi.org/10.7554/eLife.43864
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