Bovine F1Fo ATP synthase monomers bend the lipid bilayer in 2D membrane crystals

Elife. 2015 Mar 27;4:e06119. doi: 10.7554/eLife.06119.

Abstract

We have used a combination of electron cryo-tomography, subtomogram averaging, and electron crystallographic image processing to analyse the structure of intact bovine F(1)F(o) ATP synthase in 2D membrane crystals. ATPase assays and mass spectrometry analysis of the 2D crystals confirmed that the enzyme complex was complete and active. The structure of the matrix-exposed region was determined at 24 Å resolution by subtomogram averaging and repositioned into the tomographic volume to reveal the crystal packing. F(1)F(o) ATP synthase complexes are inclined by 16° relative to the crystal plane, resulting in a zigzag topology of the membrane and indicating that monomeric bovine heart F(1)F(o) ATP synthase by itself is sufficient to deform lipid bilayers. This local membrane curvature is likely to be instrumental in the formation of ATP synthase dimers and dimer rows, and thus for the shaping of mitochondrial cristae.

Keywords: biophysics; bos taurus; electron cryo-tomography; electron crystallography; membrane curvature; mitochondria; structural biology; sub-tomogram averaging.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / chemistry*
  • Animals
  • Cattle
  • Crystallization
  • Electron Microscope Tomography
  • Lipid Bilayers / chemistry*
  • Mitochondria, Heart / chemistry
  • Mitochondrial Proton-Translocating ATPases / chemistry*
  • Mitochondrial Proton-Translocating ATPases / isolation & purification
  • Mitochondrial Proton-Translocating ATPases / ultrastructure*
  • Models, Molecular
  • Myocardium / chemistry
  • Protein Conformation
  • Protein Multimerization

Substances

  • Lipid Bilayers
  • Adenosine Triphosphate
  • F1F0-ATP synthase
  • Mitochondrial Proton-Translocating ATPases

Grant support

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.