TY  - JOUR
A1  - Sousa, Joana Sofia de
A1  - Mills, Deryck J.
A1  - Vonck, Janet
A1  - Kühlbrandt, Werner
T1  - Functional asymmetry and electron flow in the bovine respirasome
T2  - eLife
N2  - Respirasomes are macromolecular assemblies of the respiratory chain complexes I, III and IV in the inner mitochondrial membrane. We determined the structure of supercomplex I1III2IV1 from bovine heart mitochondria by cryo-EM at 9 Å resolution. Most protein-protein contacts between complex I, III and IV in the membrane are mediated by supernumerary subunits. Of the two Rieske iron-sulfur cluster domains in the complex III dimer, one is resolved, indicating that this domain is immobile and unable to transfer electrons. The central position of the active complex III monomer between complex I and IV in the respirasome is optimal for accepting reduced quinone from complex I over a short diffusion distance of 11 nm, and delivering reduced cytochrome c to complex IV. The functional asymmetry of complex III provides strong evidence for directed electron flow from complex I to complex IV through the active complex III monomer in the mammalian supercomplex.
KW  - Research article
KW  - Biophysics and structural biology
KW  - Bos taurus
KW  - Cryo-em
KW  - Mitochondria
KW  - Respiratory chain
KW  - Supercomplex
Y1  - 2017
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/45001
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-450019
SN  - 2050-084X
N1  - Copyright Sousa et al. This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
VL  - 5
IS  - e21290
SP  - 1
EP  - 17
PB  - eLife Sciences Publications
CY  - Cambridge
ER  -