Structure of dimeric ATP synthase from mitochondria

An angular association of monomers induces the strong curvature of the inner membrane

authored by

Natalya V. Dudkina, Jesco Heinemeyer, Wilko Keegstra, Egbert J. Boekema, Hans Peter Braun

Abstract

Respiration in all cells depends upon synthesis of ATP by the ATP synthase complex, a rotary motor enzyme. The structure of the catalytic moiety of ATP synthase, the so-called F₁ headpiece, is well established. F ₁ is connected to the membrane-bound and ion translocating F ₀ subcomplex by a central stalk. A peripheral stalk, or stator, prevents futile rotation of the headpiece during catalysis. Although the enzyme functions as a monomer, several lines of evidence have recently suggested that monomeric ATP synthase complexes might interact to form a dimeric supercomplex in mitochondria. However, due to its fragility, the structure of ATP synthase dimers has so far not been precisely defined for any organism. Here we report the purification of a stable dimeric ATP synthase supercomplex, using mitochondria of the alga Polytomella. Structural analysis by electron microscopy and single particle analysis revealed that dimer formation is based on specific interaction of the F₀ parts, not the F₁ headpieces which are not at all in close proximity. Remarkably, the angle between the two F ₀ part is about 70°, which induces a strong local bending of the membrane. Hence, the function of ATP synthase dimerisation is to control the unique architecture of the mitochondrial inner membrane.

Organisation(s)

Institute of Plant Genetics

External Organisation(s)

University of Groningen

Type

Article

Journal

FEBS letters

Volume

579

Pages

5769-5772

No. of pages

4

ISSN

0014-5793

Publication date

06.10.2005

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Biophysics, Structural Biology, Biochemistry, Molecular Biology, Genetics, Cell Biology

Electronic version(s)

https://doi.org/10.1016/j.febslet.2005.09.065 (Access: Unknown)