5J4Z

Architecture of tight respirasome

This is a non-PDB format compatible entry.

Summary for 5J4Z

• Entry DOI: 10.2210/pdb5j4z/pdb
• EMDB information: 8130
• Descriptor: COMPLEX I ND3, COMPLEX I ND6, COMPLEX I ND4L, ... (80 entities in total)
• Functional Keywords: membrane protein complex, supercomplex, respirasome, electron transport
• Biological source: Ovis aries (SHEEP); More
• Total number of polymer chains: 89
• Total formula weight: 1285297.38

Authors

Letts, J.A.,Fiedorczuk, K.,Sazanov, L.A. (deposition date: 2016-04-01, release date: 2016-09-21, Last modification date: 2024-10-23)

Primary citation

Letts, J.A.,Fiedorczuk, K.,Sazanov, L.A.
The architecture of respiratory supercomplexes.
Nature, 537:644-648, 2016

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) 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.

PubMed: 27654913
DOI: 10.1038/nature19774

Experimental method

ELECTRON MICROSCOPY (5.8 Å)