Dimer ribbons of ATP synthase shape the inner mitochondrial membrane

EMBO J. 2008 Apr 9;27(7):1154-60. doi: 10.1038/emboj.2008.35. Epub 2008 Mar 6.


ATP synthase converts the electrochemical potential at the inner mitochondrial membrane into chemical energy, producing the ATP that powers the cell. Using electron cryo-tomography we show that the ATP synthase of mammalian mitochondria is arranged in long approximately 1-microm rows of dimeric supercomplexes, located at the apex of cristae membranes. The dimer ribbons enforce a strong local curvature on the membrane with a 17-nm outer radius. Calculations of the electrostatic field strength indicate a significant increase in charge density, and thus in the local pH gradient of approximately 0.5 units in regions of high membrane curvature. We conclude that the mitochondrial cristae act as proton traps, and that the proton sink of the ATP synthase at the apex of the compartment favours effective ATP synthesis under proton-limited conditions. We propose that the mitochondrial ATP synthase organises itself into dimer ribbons to optimise its own performance.

MeSH terms

  • Animals
  • Cattle
  • Computer Simulation
  • Dimerization
  • Electric Conductivity
  • Hydrogen-Ion Concentration
  • Mitochondrial Membranes / enzymology*
  • Mitochondrial Membranes / ultrastructure
  • Mitochondrial Proton-Translocating ATPases / chemistry*
  • Mitochondrial Proton-Translocating ATPases / metabolism*
  • Mitochondrial Proton-Translocating ATPases / ultrastructure
  • Models, Biological
  • Protein Structure, Quaternary
  • Protein Structure, Secondary
  • Rats
  • Static Electricity
  • Tomography


  • Mitochondrial Proton-Translocating ATPases