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-Structure paper
Title | The architecture of respiratory supercomplexes. |
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Journal, issue, pages | Nature, Vol. 537, Issue 7622, Page 644-648, Year 2016 |
Publish date | Sep 29, 2016 |
Authors | James A Letts / Karol Fiedorczuk / Leonid A Sazanov / |
PubMed Abstract | Mitochondrial electron transport chain complexes are organized into supercomplexes responsible for carrying out cellular respiration. Here we present three architectures of mammalian (ovine) ...Mitochondrial electron transport chain complexes are organized into supercomplexes responsible for carrying out cellular respiration. Here we present three architectures of mammalian (ovine) supercomplexes determined by cryo-electron microscopy. We identify two distinct arrangements of supercomplex CICIIICIV (the respirasome)-a major 'tight' form and a minor 'loose' form (resolved at the resolution of 5.8 Å and 6.7 Å, respectively), which may represent different stages in supercomplex assembly or disassembly. We have also determined an architecture of supercomplex CICIII at 7.8 Å resolution. All observed density can be attributed to the known 80 subunits of the individual complexes, including 132 transmembrane helices. The individual complexes form tight interactions that vary between the architectures, with complex IV subunit COX7a switching contact from complex III to complex I. The arrangement of active sites within the supercomplex may help control reactive oxygen species production. To our knowledge, these are the first complete architectures of the dominant, physiologically relevant state of the electron transport chain. |
External links | Nature / PubMed:27654913 |
Methods | EM (single particle) |
Resolution | 5.8 - 7.8 Å |
Structure data | EMDB-8128: Architecture of ovine respiratory supercomplex (I-III2-IV) conformation loose |
Chemicals | ChemComp-SF4: ChemComp-FES: ChemComp-HEM: ChemComp-CU: ChemComp-HEA: ChemComp-CUA: |
Source |
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Keywords | ELECTRON TRANSPORT / membrane protein complex / supercomplex / respirasome / MEMBRANE PROTEIN / Mitochondrial supercomplex / NADH-ubiquinone oxidoreductase / coenzyme Q-cytochrome c Oxidoreductase / cytochrome c oxidase |