8OLT

Mitochondrial complex I from Mus musculus in the active state bound with piericidin A

Summary for 8OLT

• Entry DOI: 10.2210/pdb8olt/pdb
• EMDB information: 16962
• Descriptor: NADH-ubiquinone oxidoreductase chain 3, NADH-ubiquinone oxidoreductase chain 6, NADH-ubiquinone oxidoreductase chain 4L, ... (60 entities in total)
• Functional Keywords: mitochondrial complex i, respiratory complex i, nadh:ubiquinone oxidoreductase, oxidoreductase
• Biological source: Mus musculus (house mouse); More
• Total number of polymer chains: 45
• Total formula weight: 1081224.03

Authors

Grba, D.N.,Chung, I.,Bridges, H.R.,Agip, A.N.A.,Hirst, J. (deposition date: 2023-03-30, release date: 2023-08-09, Last modification date: 2025-10-01)

Primary citation

Grba, D.N.,Chung, I.,Bridges, H.R.,Agip, A.A.,Hirst, J.
Investigation of hydrated channels and proton pathways in a high-resolution cryo-EM structure of mammalian complex I.
Sci Adv, 9:eadi1359-eadi1359, 2023

PubMed Abstract: Respiratory complex I, a key enzyme in mammalian metabolism, captures the energy released by reduction of ubiquinone by NADH to drive protons across the inner mitochondrial membrane, generating the proton-motive force for ATP synthesis. Despite remarkable advances in structural knowledge of this complicated membrane-bound enzyme, its mechanism of catalysis remains controversial. In particular, how ubiquinone reduction is coupled to proton pumping and the pathways and mechanisms of proton translocation are contested. We present a 2.4-Å resolution cryo-EM structure of complex I from mouse heart mitochondria in the closed, active (ready-to-go) resting state, with 2945 water molecules modeled. By analyzing the networks of charged and polar residues and water molecules present, we evaluate candidate pathways for proton transfer through the enzyme, for the chemical protons for ubiquinone reduction, and for the protons transported across the membrane. Last, we compare our data to the predictions of extant mechanistic models, and identify key questions to answer in future work to test them.

PubMed: 37531432
DOI: 10.1126/sciadv.adi1359

Experimental method

ELECTRON MICROSCOPY (2.84 Å)