Respiratory complex I: 'steam engine' of the cell? Journal Article

Author(s): Efremov, Rouslan G; Sazanov, Leonid A
Article Title: Respiratory complex I: 'steam engine' of the cell?
Abstract: Complex I is the first enzyme of the respiratory chain and plays a central role in cellular energy production. It has been implicated in many human neurodegenerative diseases, as well as in ageing. One of the biggest membrane protein complexes, it is an L-shaped assembly consisting of hydrophilic and membrane domains. Previously, we have determined structures of the hydrophilic domain in several redox states. Last year was marked by fascinating breakthroughs in the understanding of the complete structure. We described the architecture of the membrane domain and of the entire bacterial complex I. X-ray analysis of the larger mitochondrial enzyme has also been published. The core subunits of the bacterial and mitochondrial enzymes have remarkably similar structures. The proposed mechanism of coupling between electron transfer and proton translocation involves long-range conformational changes, coordinated in part by a long α-helix, akin to the coupling rod of a steam engine.
Keywords: bacterial enzyme; reduced nicotinamide adenine dinucleotide dehydrogenase (ubiquinone); mitochondrial enzyme
Journal Title: Current Opinion in Structural Biology
Volume: 21
Issue 4
ISSN: 0959-440X
Publisher: Elsevier  
Date Published: 2011-08-01
Start Page: 532
End Page: 540
Sponsor: The work in authors’ laboratory was funded by the Medical Research Council.
DOI: 10.1016/
Open access: no