7O71

Cryo-EM structure of a respiratory complex I

Summary for 7O71

• Entry DOI: 10.2210/pdb7o71/pdb
• EMDB information: 12742
• Descriptor: NADH-ubiquinone oxidoreductase 78 kDa subunit, Subunit NB5M of NADH:Ubiquinone Oxidoreductase (Complex I), NADH-ubiquinone oxidoreductase chain 1, ... (55 entities in total)
• Functional Keywords: complex i, nadh dehydrogenase, mitochondrion proton pumping, ubiquinone, oxidoreductase
• Biological source: Yarrowia lipolytica (Candida lipolytica); More
• Total number of polymer chains: 42
• Total formula weight: 1015124.29

Authors

Parey, K.,Vonck, J. (deposition date: 2021-04-12, release date: 2021-11-10, Last modification date: 2025-10-01)

Primary citation

Parey, K.,Lasham, J.,Mills, D.J.,Djurabekova, A.,Haapanen, O.,Yoga, E.G.,Xie, H.,Kuhlbrandt, W.,Sharma, V.,Vonck, J.,Zickermann, V.
High-resolution structure and dynamics of mitochondrial complex I-Insights into the proton pumping mechanism.
Sci Adv, 7:eabj3221-eabj3221, 2021

PubMed Abstract: Mitochondrial NADH:ubiquinone oxidoreductase (complex I) is a 1-MDa membrane protein complex with a central role in energy metabolism. Redox-driven proton translocation by complex I contributes substantially to the proton motive force that drives ATP synthase. Several structures of complex I from bacteria and mitochondria have been determined, but its catalytic mechanism has remained controversial. We here present the cryo-EM structure of complex I from at 2.1-Å resolution, which reveals the positions of more than 1600 protein-bound water molecules, of which ~100 are located in putative proton translocation pathways. Another structure of the same complex under steady-state activity conditions at 3.4-Å resolution indicates conformational transitions that we associate with proton injection into the central hydrophilic axis. By combining high-resolution structural data with site-directed mutagenesis and large-scale molecular dynamic simulations, we define details of the proton translocation pathways and offer insights into the redox-coupled proton pumping mechanism of complex I.

PubMed: 34767441
DOI: 10.1126/sciadv.abj3221

Experimental method

ELECTRON MICROSCOPY (2.4 Å)