6hu9
III2-IV2 mitochondrial respiratory supercomplex from S. cerevisiaeIII2-IV2 mitochondrial respiratory supercomplex from S. cerevisiae
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. [COX3_YEAST] Subunits I, II and III form the functional core of the enzyme complex. [COX6_YEAST] This is the heme A-containing chain of cytochrome c oxidase, the terminal oxidase in mitochondrial electron transport. [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. [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. [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. [COX9_YEAST] This small integral protein plays a role in holoenzyme assembly or stability. [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. Publication Abstract from PubMedCytochrome c oxidase (complex IV, CIV) is known in mammals to exist independently or in association with other respiratory proteins to form supercomplexes (SCs). In Saccharomyces cerevisiae, CIV is found solely in an SC with cytochrome bc1 (complex III, CIII). Here, we present the cryogenic electron microscopy (cryo-EM) structure of S. cerevisiae CIV in a III2IV2 SC at 3.3 A resolution. While overall similarity to mammalian homologs is high, we found notable differences in the supernumerary subunits Cox26 and Cox13; the latter exhibits a unique arrangement that precludes CIV dimerization as seen in bovine. A conformational shift in the matrix domain of Cox5A-involved in allosteric inhibition by ATP-may arise from its association with CIII. The CIII-CIV arrangement highlights a conserved interaction interface of CIII, albeit one occupied by complex I in mammalian respirasomes. We discuss our findings in the context of the potential impact of SC formation on CIV regulation. Structure of yeast cytochrome c oxidase in a supercomplex with cytochrome bc1.,Hartley AM, Lukoyanova N, Zhang Y, Cabrera-Orefice A, Arnold S, Meunier B, Pinotsis N, Marechal A Nat Struct Mol Biol. 2019 Jan;26(1):78-83. doi: 10.1038/s41594-018-0172-z. Epub, 2018 Dec 31. PMID:30598554[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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