National Health and Medical Research Council (Australia)
1146403
オーストラリア
引用
ジャーナル: Elife / 年: 2019 タイトル: Cryo-EM reveals distinct conformations of ATP synthase on exposure to ATP. 著者: Meghna Sobti / Robert Ishmukhametov / James C Bouwer / Anita Ayer / Cacang Suarna / Nicola J Smith / Mary Christie / Roland Stocker / Thomas M Duncan / Alastair G Stewart / 要旨: ATP synthase produces the majority of cellular energy in most cells. We have previously reported cryo-EM maps of autoinhibited ATP synthase imaged without addition of nucleotide (Sobti et al. 2016), ...ATP synthase produces the majority of cellular energy in most cells. We have previously reported cryo-EM maps of autoinhibited 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, 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 ATP synthase when ATP binding prevents the ε C-terminal domain from entering the inhibitory 'up' state.