Cryo-EM reveals distinct conformations of E. coli ATP synthase on exposure to ATP

Journal article

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.

Authors: Sobti, M; Ishmukhametov, R; Bouwer, JC; Ayer, A; Suarna, C

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: eLife Sciences Publications
• Journal: eLife
• Volume: 8
• Article number: e43864
• Publication date: 2019-03-26
• Acceptance date: 2019-03-25
• DOI: 10.7554/elife.43864
• EISSN: 2050-084X
• Pmid: 30912741
• Language: English
• Keywords: protein subunits; cryoelectron microscopy; Escherichia coli proteins; protein conformation; adenosine triphosphate; FFR; mitochondrial proton-translocating ATPases