6t15

Structural highlights

Function

[COX1_YEAST] Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Subunits 1-3 form the functional core of the enzyme complex. CO I is the catalytic subunit of the enzyme. Electrons originating in cytochrome c are transferred via the copper A center of subunit 2 and heme A of subunit 1 to the bimetallic center formed by heme A3 and copper B. [COX13_YEAST] Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Not necessary for assembly of the enzyme complex but interacts with ATP and thereby modulates the enzyme activity. [QCR7_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR7 is involved in redox-linked proton pumping. [QCR2_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR2 is required for the assembly of the complex. [QCR1_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. COR1 may mediate formation of the complex between cytochromes c and c1. [RCF2_YEAST] Assembly factor that plays a role in the assembly of the respiratory chain supercomplexes (SCs) composed of ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII) and cytochrome c oxidase (complex IV, CIV). May be required for late-stage assembly of the COX12 and COX13 subunits (PubMed:22342701, PubMed:22310663). Required for the generation and maintenance of a normal proton motive force (PMF) across the inner mitochondrial membrane (IMM) by preventing proton leakage through an inactive population of CIV that accumulates when RCF1 and/or RCF2 proteins are absent (PubMed:30683696, PubMed:31591265).^{[1] [2] [3] [4]} [COX6_YEAST] This is the heme A-containing chain of cytochrome c oxidase, the terminal oxidase in mitochondrial electron transport. [COX3_YEAST] Subunits I, II and III form the functional core of the enzyme complex. [QCR6_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR6 may mediate formation of the complex between cytochromes c and c1. [CYB_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. [QCR9_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR9 is required for formation of a fully functional complex. [COX2_YEAST] Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Subunits 1-3 form the functional core of the enzyme complex. Subunit 2 transfers the electrons from cytochrome c via its binuclear copper A center to the bimetallic center of the catalytic subunit 1. [COX12_YEAST] This protein is one of the nuclear-coded polypeptide chains of cytochrome c oxidase, the terminal oxidase in mitochondrial electron transport. This protein may be one of the heme-binding subunits of the oxidase. [COX5B_YEAST] Component of the cytochrome c oxidase, the last enzyme in the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes succinate dehydrogenase (complex II, CII), ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to transfer electrons derived from NADH and succinate to molecular oxygen, creating an electrochemical gradient over the inner membrane that drives transmembrane transport and the ATP synthase. Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Electrons originating from reduced cytochrome c in the intermembrane space (IMS) are transferred via the dinuclear copper A center (CU(A)) of COX2 and heme A of COX1 to the active site in COX1, a binuclear center (BNC) formed by heme A3 and copper B (CU(B)). The BNC reduces molecular oxygen to 2 water molecules using 4 electrons from cytochrome c in the IMS and 4 protons from the mitochondrial matrix.[UniProtKB:P00424] [QCR8_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR8, together with cytochrome b, binds to ubiquinone. [CY1_YEAST] Heme-containing component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. [COX9_YEAST] This small integral protein plays a role in holoenzyme assembly or stability. [QCR10_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is part of the mitochondrial respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c. QCR10 is required for stable association of the iron-sulfur protein with the complex. [UCRI_YEAST] Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is a respiratory chain that generates an electrochemical potential coupled to ATP synthesis. The complex couples electron transfer from ubiquinol to cytochrome c.

References

1. ↑ Strogolova V, Furness A, Robb-McGrath M, Garlich J, Stuart RA. Rcf1 and Rcf2, members of the hypoxia-induced gene 1 protein family, are critical components of the mitochondrial cytochrome bc1-cytochrome c oxidase supercomplex. Mol Cell Biol. 2012 Apr;32(8):1363-73. doi: 10.1128/MCB.06369-11. Epub 2012 Feb, 6. PMID:22310663 doi:http://dx.doi.org/10.1128/MCB.06369-11
2. ↑ Vukotic M, Oeljeklaus S, Wiese S, Vogtle FN, Meisinger C, Meyer HE, Zieseniss A, Katschinski DM, Jans DC, Jakobs S, Warscheid B, Rehling P, Deckers M. Rcf1 mediates cytochrome oxidase assembly and respirasome formation, revealing heterogeneity of the enzyme complex. Cell Metab. 2012 Mar 7;15(3):336-47. doi: 10.1016/j.cmet.2012.01.016. Epub 2012, Feb 16. PMID:22342701 doi:http://dx.doi.org/10.1016/j.cmet.2012.01.016
3. ↑ Strogolova V, Hoang NH, Hosler J, Stuart RA. The yeast mitochondrial proteins Rcf1 and Rcf2 support the enzymology of the cytochrome c oxidase complex and generation of the proton motive force. J Biol Chem. 2019 Mar 29;294(13):4867-4877. doi: 10.1074/jbc.RA118.006888. Epub, 2019 Jan 25. PMID:30683696 doi:http://dx.doi.org/10.1074/jbc.RA118.006888
4. ↑ Hoang NH, Strogolova V, Mosley JJ, Stuart RA, Hosler J. Hypoxia-inducible gene domain 1 proteins in yeast mitochondria protect against proton leak through complex IV. J Biol Chem. 2019 Nov 15;294(46):17669-17677. doi: 10.1074/jbc.RA119.010317. Epub, 2019 Oct 7. PMID:31591265 doi:http://dx.doi.org/10.1074/jbc.RA119.010317
5. ↑ Hartley AM, Meunier B, Pinotsis N, Marechal A. Rcf2 revealed in cryo-EM structures of hypoxic isoforms of mature mitochondrial III-IV supercomplexes. Proc Natl Acad Sci U S A. 2020 Apr 14. pii: 1920612117. doi:, 10.1073/pnas.1920612117. PMID:32291341 doi:http://dx.doi.org/10.1073/pnas.1920612117