Journal articles: 'Assembly of cytochrom c oxidase'

1

Taanman, J. W., and S. L. Williams. "Assembly of cytochrome c oxidase: what can we learn from patients with cytochrome c oxidase deficiency?" Biochemical Society Transactions 29, no. 4 (August 1, 2001): 446–51. http://dx.doi.org/10.1042/bst0290446.

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Cytochrome c oxidase is an intricate metalloprotein that transfers electrons from cytochrome c to oxygen in the last step of the mitochondrial respiratory chain. It uses the free energy of this reaction to sustain a transmembrane electrochemical gradient of protons. Site-directed mutagenesis studies of bacterial terminal oxidases and the recent availability of refined crystal structures of the enzyme are rapidly expanding the understanding of the coupling mechanism between electron transfer and proton translocation. In contrast, relatively little is known about the assembly pathway of cytochrome c oxidase. Studies in yeast have indicated that assembly is dependent on numerous proteins in addition to the structural subunits and prosthetic groups. Human homologues of a number of these assembly factors have been identified and some are now known to be involved in disease. To dissect the assembly pathway of cytochrome c oxidase, we are characterizing tissues and cell cultures derived from patients with genetically defined cytochrome c oxidase deficiency, using biochemical, biophysical and immunological techniques. These studies have allowed us to identify some of the steps of the assembly process.

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Feissner, Robert E., Caroline S. Beckett, Jennifer A. Loughman, and Robert G. Kranz. "Mutations in Cytochrome Assembly and Periplasmic Redox Pathways in Bordetella pertussis." Journal of Bacteriology 187, no. 12 (June 15, 2005): 3941–49. http://dx.doi.org/10.1128/jb.187.12.3941-3949.2005.

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ABSTRACT Transposon mutagenesis of Bordetella pertussis was used to discover mutations in the cytochrome c biogenesis pathway called system II. Using a tetramethyl-p-phenylenediamine cytochrome c oxidase screen, 27 oxidase-negative mutants were isolated and characterized. Nine mutants were still able to synthesize c-type cytochromes and possessed insertions in the genes for cytochrome c oxidase subunits (ctaC, -D, and -E), heme a biosynthesis (ctaB), assembly of cytochrome c oxidase (sco2), or ferrochelatase (hemZ). Eighteen mutants were unable to synthesize all c-type cytochromes. Seven of these had transposons in dipZ (dsbD), encoding the transmembrane thioreduction protein, and all seven mutants were corrected for cytochrome c assembly by exogenous dithiothreitol, which was consistent with the cytochrome c cysteinyl residues of the CXXCH motif requiring periplasmic reduction. The remaining 11 insertions were located in the ccsBA operon, suggesting that with the appropriate thiol-reducing environment, the CcsB and CcsA proteins comprise the entire system II biosynthetic pathway. Antiserum to CcsB was used to show that CcsB is absent in ccsA mutants, providing evidence for a stable CcsA-CcsB complex. No mutations were found in the genes necessary for disulfide bond formation (dsbA or dsbB). To examine whether the periplasmic disulfide bond pathway is required for cytochrome c biogenesis in B. pertussis, a targeted knockout was made in dsbB. The DsbB− mutant makes holocytochromes c like the wild type does and secretes and assembles the active periplasmic alkaline phosphatase. A dipZ mutant is not corrected by a dsbB mutation. Alternative mechanisms to oxidize disulfides in B. pertussis are analyzed and discussed.

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Bengtsson, Jenny, Claes von Wachenfeldt, Lena Winstedt, Per Nygaard, and Lars Hederstedt. "CtaG is required for formation of active cytochrome c oxidase in Bacillus subtilis." Microbiology 150, no. 2 (February 1, 2004): 415–25. http://dx.doi.org/10.1099/mic.0.26691-0.

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The Gram-positive bacterium Bacillus subtilis contains two respiratory oxidases of the haem-copper superfamily: cytochrome aa 3, which is a quinol oxidase, and cytochrome caa 3, which is a cytochrome c oxidase. Cytochrome c oxidase uniquely contains a di-copper centre, CuA. B. subtilis CtaG is a membrane protein encoded by the same gene cluster as that which encodes the subunits of cytochrome c oxidase. The role of B. subtilis CtaG and orthologous proteins present in many other Gram-positive bacteria has remained unexplored. The sequence of CtaG is unrelated to that of CtaG/Cox11p of proteobacteria and eukaryotic cells. This study shows that B. subtilis CtaG is essential for the formation of active cytochrome caa 3 but is not required for assembly of the core subunits I and II with haem in the membrane and it has no role in the synthesis of active cytochrome aa 3. B. subtilis YpmQ, a homologue to Sco1p of eukaryotic cells, is also a membrane-bound cytochrome c oxidase-specific assembly factor. Properties of CtaG- and YpmQ-deficient mutants were compared. Cells lacking YpmQ showed a low cytochrome c oxidase activity and this defect was suppressed by the supplementation of the growth medium with copper ions. It has previously been proposed that YpmQ/Sco1p is involved in synthesis of the CuA centre. The results of this study are consistent with this proposal but the exact role of YpmQ in assembly of cytochrome c oxidase remains to be elucidated.

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Bareth, Bettina, Miroslav Nikolov, Isotta Lorenzi, Markus Hildenbeutel, David U. Mick, Christin Helbig, Henning Urlaub, Martin Ott, Peter Rehling, and Sven Dennerlein. "Oms1 associates with cytochrome c oxidase assembly intermediates to stabilize newly synthesized Cox1." Molecular Biology of the Cell 27, no. 10 (May 15, 2016): 1570–80. http://dx.doi.org/10.1091/mbc.e15-12-0811.

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The mitochondrial cytochrome c oxidase assembles in the inner membrane from subunits of dual genetic origin. The assembly process of the enzyme is initiated by membrane insertion of the mitochondria-encoded Cox1 subunit. During complex maturation, transient assembly intermediates, consisting of structural subunits and specialized chaperone-like assembly factors, are formed. In addition, cofactors such as heme and copper have to be inserted into the nascent complex. To regulate the assembly process, the availability of Cox1 is under control of a regulatory feedback cycle in which translation of COX1 mRNA is stalled when assembly intermediates of Cox1 accumulate through inactivation of the translational activator Mss51. Here we isolate a cytochrome c oxidase assembly intermediate in preparatory scale from coa1Δ mutant cells, using Mss51 as bait. We demonstrate that at this stage of assembly, the complex has not yet incorporated the heme a cofactors. Using quantitative mass spectrometry, we define the protein composition of the assembly intermediate and unexpectedly identify the putative methyltransferase Oms1 as a constituent. Our analyses show that Oms1 participates in cytochrome c oxidase assembly by stabilizing newly synthesized Cox1.

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Watson, Shane A., and Gavin P. McStay. "Functions of Cytochrome c Oxidase Assembly Factors." International Journal of Molecular Sciences 21, no. 19 (September 30, 2020): 7254. http://dx.doi.org/10.3390/ijms21197254.

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Cytochrome c oxidase is the terminal complex of eukaryotic oxidative phosphorylation in mitochondria. This process couples the reduction of electron carriers during metabolism to the reduction of molecular oxygen to water and translocation of protons from the internal mitochondrial matrix to the inter-membrane space. The electrochemical gradient formed is used to generate chemical energy in the form of adenosine triphosphate to power vital cellular processes. Cytochrome c oxidase and most oxidative phosphorylation complexes are the product of the nuclear and mitochondrial genomes. This poses a series of topological and temporal steps that must be completed to ensure efficient assembly of the functional enzyme. Many assembly factors have evolved to perform these steps for insertion of protein into the inner mitochondrial membrane, maturation of the polypeptide, incorporation of co-factors and prosthetic groups and to regulate this process. Much of the information about each of these assembly factors has been gleaned from use of the single cell eukaryote Saccharomyces cerevisiae and also mutations responsible for human disease. This review will focus on the assembly factors of cytochrome c oxidase to highlight some of the outstanding questions in the assembly of this vital enzyme complex.

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Capaldi, Roderick A. "Structure and assembly of cytochrome c oxidase." Archives of Biochemistry and Biophysics 280, no. 2 (August 1990): 252–62. http://dx.doi.org/10.1016/0003-9861(90)90327-u.

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7

Kulawiak, B., N. Gebert, C. Schütze, A. Schulze-Specking, N. Wiedemann, and N. Pfanner. "Pet117 — Assembly factor of cytochrome c oxidase." Biochimica et Biophysica Acta (BBA) - Bioenergetics 1817 (October 2012): S109. http://dx.doi.org/10.1016/j.bbabio.2012.06.293.

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8

Barrientos, Antoni. "Redox Regulation of Cytochrome C Oxidase Assembly." Biophysical Journal 112, no. 3 (February 2017): 4a. http://dx.doi.org/10.1016/j.bpj.2016.11.040.

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Forsha, D., C. Church, P. Wazny, and R. O. Poyton. "Structure and function of Pet100p, a molecular chaperone required for the assembly of cytochrome c oxidase in Saccharomyces cerevisiae." Biochemical Society Transactions 29, no. 4 (August 1, 2001): 436–41. http://dx.doi.org/10.1042/bst0290436.

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The assembly of cytochrome c oxidase in the inner mitochondrial membranes of eukaryotic cells requires the protein products of a large number of nuclear genes. In yeast, some of these act globally and affect the assembly of several respiratory-chain protein complexes, whereas others act in a cytochrome c oxidase-specific fashion. Many of these yeast proteins have human counterparts, which when mutated lead to energy-related diseases. One of these proteins, Pet100p, is a novel molecular chaperone that functions to incorporate a subcomplex containing cytochrome c oxidase subunits VII, VIIa and VIII into holo-(cytochrome c oxidase). Here we report the topological disposition of Pet100p in the inner mitochondrial membrane and show that its C-terminal domain is essential for its function as a cytochrome c oxidase-specific ‘assembly facilitator’.

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10

Perez-Martinez, Xochitl, Christine A. Butler, Miguel Shingu-Vazquez, and Thomas D. Fox. "Dual Functions of Mss51 Couple Synthesis of Cox1 to Assembly of Cytochrome c Oxidase in Saccharomyces cerevisiae Mitochondria." Molecular Biology of the Cell 20, no. 20 (October 15, 2009): 4371–80. http://dx.doi.org/10.1091/mbc.e09-06-0522.

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Functional interactions of the translational activator Mss51 with both the mitochondrially encoded COX1 mRNA 5′-untranslated region and with newly synthesized unassembled Cox1 protein suggest that it has a key role in coupling Cox1 synthesis with assembly of cytochrome c oxidase. Mss51 is present at levels that are near rate limiting for expression of a reporter gene inserted at COX1 in mitochondrial DNA, and a substantial fraction of Mss51 is associated with Cox1 protein in assembly intermediates. Thus, sequestration of Mss51 in assembly intermediates could limit Cox1 synthesis in wild type, and account for the reduced Cox1 synthesis caused by most yeast mutations that block assembly. Mss51 does not stably interact with newly synthesized Cox1 in a mutant lacking Cox14, suggesting that the failure of nuclear cox14 mutants to decrease Cox1 synthesis, despite their inability to assemble cytochrome c oxidase, is due to a failure to sequester Mss51. The physical interaction between Mss51 and Cox14 is dependent upon Cox1 synthesis, indicating dynamic assembly of early cytochrome c oxidase intermediates nucleated by Cox1. Regulation of COX1 mRNA translation by Mss51 seems to be an example of a homeostatic mechanism in which a positive effector of gene expression interacts with the product it regulates in a posttranslational assembly process.

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11

Swem, Danielle L., Lee R. Swem, Aaron Setterdahl, and Carl E. Bauer. "Involvement of SenC in Assembly of Cytochrome c Oxidase in Rhodobacter capsulatus." Journal of Bacteriology 187, no. 23 (December 1, 2005): 8081–87. http://dx.doi.org/10.1128/jb.187.23.8081-8087.2005.

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ABSTRACT SenC, a Sco1 homolog found in the purple photosynthetic bacteria, has been implicated in affecting photosynthesis and respiratory gene expression, as well as assembly of cytochrome c oxidase. In this study, we show that SenC from Rhodobacter capsulatus is involved in the assembly of a fully functional cbb 3-type cytochrome c oxidase, as revealed by decreased cytochrome c oxidase activity in a senC mutant. We also show that a putative copper-binding site in SenC is required for activity and that a SenC deletion phenotype can be rescued by the addition of exogenous copper to the growth medium. In addition, we demonstrate that a SenC mutation has an indirect effect on gene expression caused by a reduction in cytochrome c oxidase activity. A model is proposed whereby a reduction in cytochrome c oxidase activity impedes the flow of electrons through the respiratory pathway, thereby affecting the oxidation/reduction state of the ubiquinone pool, leading to alterations of photosystem and respiratory gene expression.

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12

Pawlik, Grzegorz, Carmen Kulajta, Ilie Sachelaru, Sebastian Schröder, Barbara Waidner, Petra Hellwig, Fevzi Daldal, and Hans-Georg Koch. "The Putative Assembly Factor CcoH Is Stably Associated with the cbb3-Type Cytochrome Oxidase." Journal of Bacteriology 192, no. 24 (October 15, 2010): 6378–89. http://dx.doi.org/10.1128/jb.00988-10.

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ABSTRACT Cytochrome oxidases are perfect model substrates for analyzing the assembly of multisubunit complexes because the need for cofactor incorporation adds an additional level of complexity to their assembly. cbb 3-type cytochrome c oxidases (cbb 3-Cox) consist of the catalytic subunit CcoN, the membrane-bound c-type cytochrome subunits CcoO and CcoP, and the CcoQ subunit, which is required for cbb 3-Cox stability. Biogenesis of cbb 3-Cox proceeds via CcoQP and CcoNO subcomplexes, which assemble into the active cbb 3-Cox. Most bacteria expressing cbb 3-Cox also contain the ccoGHIS genes, which encode putative cbb 3-Cox assembly factors. Their exact function, however, has remained unknown. Here we analyzed the role of CcoH in cbb 3-Cox assembly and showed that CcoH is a single spanning-membrane protein with an N-terminus-out-C-terminus-in (Nout-Cin) topology. In its absence, neither the fully assembled cbb 3-Cox nor the CcoQP or CcoNO subcomplex was detectable. By chemical cross-linking, we demonstrated that CcoH binds primarily via its transmembrane domain to the CcoP subunit of cbb 3-Cox. A second hydrophobic stretch, which is located at the C terminus of CcoH, appears not to be required for contacting CcoP, but deleting it prevents the formation of the active cbb 3-Cox. This suggests that the second hydrophobic domain is required for merging the CcoNO and CcoPQ subcomplexes into the active cbb 3-Cox. Surprisingly, CcoH does not seem to interact only transiently with the cbb 3-Cox but appears to stay tightly associated with the active, fully assembled complex. Thus, CcoH behaves more like a bona fide subunit of the cbb 3-Cox than an assembly factor per se.

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Taanman, J. W., and S. L. Williams. "Assembly of cytochrome-c oxidase - What can we learn from patients with cytochrome-c oxidase deficiency?" Biochemical Society Transactions 29, no. 3 (June 1, 2001): A53. http://dx.doi.org/10.1042/bst029a053.

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14

Diaz, Francisca, Hirokazu Fukui, Sofia Garcia, and Carlos T. Moraes. "Cytochrome c Oxidase Is Required for the Assembly/Stability of Respiratory Complex I in Mouse Fibroblasts." Molecular and Cellular Biology 26, no. 13 (July 1, 2006): 4872–81. http://dx.doi.org/10.1128/mcb.01767-05.

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ABSTRACT Cytochrome c oxidase (COX) biogenesis requires COX10, which encodes a protoheme:heme O farnesyl transferase that participates in the biosynthesis of heme a. We created COX10 knockout mouse cells that lacked cytochrome aa3 , were respiratory deficient, had no detectable complex IV activity, and were unable to assemble COX. Unexpectedly, the levels of respiratory complex I were markedly reduced in COX10 knockout clones. Pharmacological inhibition of COX did not affect the levels of complex I, and transduction of knockout cells with lentivirus expressing wild-type or mutant COX10 (retaining residual activity) restored complex I to normal levels. Pulse-chase experiments could not detect newly assembled complex I, suggesting that either COX is required for assembly of complex I or the latter is quickly degraded. These results suggest that in rapidly dividing cells, complex IV is required for complex I assembly or stability.

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Braun, Martin, and Linda Thöny-Meyer. "Cytochrome c Maturation and the Physiological Role of c-Type Cytochromes in Vibrio cholerae." Journal of Bacteriology 187, no. 17 (September 1, 2005): 5996–6004. http://dx.doi.org/10.1128/jb.187.17.5996-6004.2005.

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ABSTRACT Vibrio cholerae lives in different habitats, varying from aquatic ecosystems to the human intestinal tract. The organism has acquired a set of electron transport pathways for aerobic and anaerobic respiration that enable adaptation to the various environmental conditions. We have inactivated the V. cholerae ccmE gene, which is required for cytochrome c biogenesis. The resulting strain is deficient of all c-type cytochromes and allows us to characterize the physiological role of these proteins. Under aerobic conditions in rich medium, V. cholerae produces at least six c-type cytochromes, none of which is required for growth. Wild-type V. cholerae produces active fumarate reductase, trimethylamine N-oxide reductase, cbb 3 oxidase, and nitrate reductase, of which only the fumarate reductase does not require maturation of c-type cytochromes. The reduction of nitrate in the medium resulted in the accumulation of nitrite, which is toxic for the cells. This suggests that V. cholerae is able to scavenge nitrate from the environment only in the presence of other nitrite-reducing organisms. The phenotypes of cytochrome c-deficient V. cholerae were used in a transposon mutagenesis screening to search for additional genes required for cytochrome c maturation. Over 55,000 mutants were analyzed for nitrate reductase and cbb 3 oxidase activity. No transposon insertions other than those within the ccm genes for cytochrome c maturation and the dsbD gene, which encodes a disulphide bond reductase, were found. In addition, the role of a novel CcdA-like protein in cbb 3 oxidase assembly is discussed.

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Barrientos, Antoni, Danielle Pierre, Johnson Lee, and Alexander Tzagoloff. "Cytochrome oxidase assembly does not require catalytically active cytochrome c." Journal of Biological Chemistry 278, no. 43 (October 2003): 42728. http://dx.doi.org/10.1016/s0021-9258(20)82819-1.

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17

Nijtmans, Leo G. J., Jan-Willem Taanman, Anton O. Muijsers, Dave Speijer, and Coby Van den Bogert. "Assembly of cytochrome-c oxidase in cultured human cells." European Journal of Biochemistry 254, no. 2 (June 1998): 389–94. http://dx.doi.org/10.1046/j.1432-1327.1998.2540389.x.

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18

Mick, David U., Thomas D. Fox, and Peter Rehling. "Inventory control: cytochrome c oxidase assembly regulates mitochondrial translation." Nature Reviews Molecular Cell Biology 12, no. 1 (December 22, 2010): 14–20. http://dx.doi.org/10.1038/nrm3029.

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19

Fontanesi, Flavia, Iliana C. Soto, Darryl Horn, and Antoni Barrientos. "Mss51 and Ssc1 Facilitate Translational Regulation of Cytochrome c Oxidase Biogenesis." Molecular and Cellular Biology 30, no. 1 (October 26, 2009): 245–59. http://dx.doi.org/10.1128/mcb.00983-09.

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ABSTRACT The intricate biogenesis of multimeric organellar enzymes of dual genetic origin entails several levels of regulation. In Saccharomyces cerevisiae, mitochondrial cytochrome c oxidase (COX) assembly is regulated translationally. Synthesis of subunit 1 (Cox1) is contingent on the availability of its assembly partners, thereby acting as a negative feedback loop that coordinates COX1 mRNA translation with Cox1 utilization during COX assembly. The COX1 mRNA-specific translational activator Mss51 plays a fundamental role in this process. Here, we report that Mss51 successively interacts with the COX1 mRNA translational apparatus, newly synthesized Cox1, and other COX assembly factors during Cox1 maturation/assembly. Notably, the mitochondrial Hsp70 chaperone Ssc1 is shown to be an Mss51 partner throughout its metabolic cycle. We conclude that Ssc1, by interacting with Mss51 and Mss51-containing complexes, plays a critical role in Cox1 biogenesis, COX assembly, and the translational regulation of these processes.

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Su, Chen-Hsien, Gavin P. McStay, and Alexander Tzagoloff. "The Cox3p assembly module of yeast cytochrome oxidase." Molecular Biology of the Cell 25, no. 7 (April 2014): 965–76. http://dx.doi.org/10.1091/mbc.e13-10-0575.

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Yeast cytochrome oxidase (COX) was previously inferred to assemble from three modules, each containing one of the three mitochondrially encoded subunits and a different subset of the eight nuclear gene products that make up this respiratory complex. Pull-down assays of pulse-labeled mitochondria enabled us to characterize Cox3p subassemblies that behave as COX precursors and contain Cox4p, Cox7p, and Cox13p. Surprisingly, Cox4p is a constituent of two other complexes, one of which was previously proposed to be an intermediate of Cox1p biogenesis. This suggests that Cox4p, which contacts Cox1p and Cox3p in the holoenzyme, can be incorporated into COX by two alternative pathways. In addition to subunits of COX, some Cox3p intermediates contain Rcf1p, a protein associated with the supercomplex that stabilizes the interaction of COX with the bc1 (ubiquinol-cytochrome c reductase) complex. Finally, our results indicate that although assembly of the Cox1p module is not contingent on the presence of Cox3p, the converse is not true, as none of the Cox3p subassemblies were detected in a mutant blocked in translation of Cox1p. These studies support our proposal that Cox3p and Cox1p are separate assembly modules with unique compositions of ancillary factors and subunits derived from the nuclear genome.

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Mick, David U., Karina Wagner, Martin van der Laan, Ann E. Frazier, Inge Perschil, Magdalena Pawlas, Helmut E. Meyer, Bettina Warscheid, and Peter Rehling. "Shy1 couples Cox1 translational regulation to cytochrome c oxidase assembly." EMBO Journal 26, no. 20 (September 20, 2007): 4347–58. http://dx.doi.org/10.1038/sj.emboj.7601862.

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22

Spricigo, Roberto, Roman Dronov, K. V. Rajagopalan, Fred Lisdat, Silke Leimkühler, Frieder W. Scheller, and Ulla Wollenberger. "Electrocatalytically functional multilayer assembly of sulfite oxidase and cytochrome c." Soft Matter 4, no. 5 (2008): 972. http://dx.doi.org/10.1039/b717694e.

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23

Poyton, R. O., C. Church, D. Forsha, P. Wazny, and C. Dagsgaard. "Assembly of Cytochrome c Oxidase: Implications for Aging and Disease." Biochemical Society Transactions 29, no. 3 (June 1, 2001): A52. http://dx.doi.org/10.1042/bst029a052b.

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24

Soto, Ileana C., Flavia Fontanesi, Jingjing Liu, and Antoni Barrientos. "Biogenesis and assembly of eukaryotic cytochrome c oxidase catalytic core." Biochimica et Biophysica Acta (BBA) - Bioenergetics 1817, no. 6 (June 2012): 883–97. http://dx.doi.org/10.1016/j.bbabio.2011.09.005.

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Banting, Graham S., and D. Moira Glerum. "Mutational Analysis of the Saccharomyces cerevisiae Cytochrome c Oxidase Assembly Protein Cox11p." Eukaryotic Cell 5, no. 3 (March 2006): 568–78. http://dx.doi.org/10.1128/ec.5.3.568-578.2006.

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ABSTRACT Cox11p is an integral protein of the inner mitochondrial membrane that is essential for cytochrome c oxidase assembly. The bulk of the protein is located in the intermembrane space and displays high levels of evolutionary conservation. We have analyzed a collection of site-directed and random cox11 mutants in an effort to further define essential portions of the molecule. Of the alleles studied, more than half had no apparent effect on Cox11p function. Among the respiration deficiency-encoding alleles, we identified three distinct phenotypes, which included a set of mutants with a misassembled or partially assembled cytochrome oxidase, as indicated by a blue-shifted cytochrome aa 3 peak. In addition to the shifted spectral signal, these mutants also display a specific reduction in the levels of subunit 1 (Cox1p). Two of these mutations are likely to occlude a surface pocket behind the copper-binding domain in Cox11p, based on analogy with the Sinorhizobium meliloti Cox11 solution structure, thereby suggesting that this pocket is crucial for Cox11p function. Sequential deletions of the matrix portion of Cox11p suggest that this domain is not functional beyond the residues involved in mitochondrial targeting and membrane insertion. In addition, our studies indicate that Δcox11, like Δsco1, displays a specific hypersensitivity to hydrogen peroxide. Our studies provide the first evidence at the level of the cytochrome oxidase holoenzyme that Cox1p is the in vivo target for Cox11p and suggest that Cox11p may also have a role in the response to hydrogen peroxide exposure.

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Böttinger, Lena, Bernard Guiard, Silke Oeljeklaus, Bogusz Kulawiak, Nicole Zufall, Nils Wiedemann, Bettina Warscheid, Martin van der Laan, and Thomas Becker. "A complex of Cox4 and mitochondrial Hsp70 plays an important role in the assembly of the cytochrome c oxidase." Molecular Biology of the Cell 24, no. 17 (September 2013): 2609–19. http://dx.doi.org/10.1091/mbc.e13-02-0106.

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The formation of the mature cytochrome c oxidase (complex IV) involves the association of nuclear- and mitochondria-encoded subunits. The assembly of nuclear-encoded subunits like cytochrome c oxidase subunit 4 (Cox4) into the mature complex is poorly understood. Cox4 is crucial for the stability of complex IV. To find specific biogenesis factors, we analyze interaction partners of Cox4 by affinity purification and mass spectroscopy. Surprisingly, we identify a complex of Cox4, the mitochondrial Hsp70 (mtHsp70), and its nucleotide-exchange factor mitochondrial GrpE (Mge1). We generate a yeast mutant of mtHsp70 specifically impaired in the formation of this novel mtHsp70-Mge1-Cox4 complex. Strikingly, the assembly of Cox4 is strongly decreased in these mutant mitochondria. Because Cox4 is a key factor for the biogenesis of complex IV, we conclude that the mtHsp70-Mge1-Cox4 complex plays an important role in the formation of cytochrome c oxidase. Cox4 arrests at this chaperone complex in the absence of mature complex IV. Thus the mtHsp70-Cox4 complex likely serves as a novel delivery system to channel Cox4 into the assembly line when needed.

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Horan, Susannah, Ingrid Bourges, Jan-Willem Taanman, and Brigitte Meunier. "Analysis of COX2 mutants reveals cytochrome oxidase subassemblies in yeast." Biochemical Journal 390, no. 3 (September 5, 2005): 703–8. http://dx.doi.org/10.1042/bj20050598.

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Cytochrome oxidase catalyses the reduction of oxygen to water. The mitochondrial enzyme contains up to 13 subunits, 11 in yeast, of which three, Cox1p, Cox2p and Cox3p, are mitochondrially encoded. The assembly pathway of this complex is still poorly understood. Its study in yeast has been so far impeded by the rapid turnover of unassembled subunits of the enzyme. In the present study, immunoblot analysis of blue native gels of yeast wild-type and Cox2p mutants revealed five cytochrome oxidase complexes or subcomplexes: a, b, c, d and f; a is likely to be the fully assembled enzyme; b lacks Cox6ap; d contains Cox7p and/or Cox7ap; f represents unassembled Cox1p; and c, observed only in the Cox2p mutants, contains Cox1p, Cox3p, Cox5p and Cox6p and lacks the other subunits. The identification of these novel cytochrome oxidase subcomplexes should encourage the reexamination of other yeast mutants.

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Box, Jodie M., Jasvinder Kaur, and Rosemary A. Stuart. "MrpL35, a mitospecific component of mitoribosomes, plays a key role in cytochrome c oxidase assembly." Molecular Biology of the Cell 28, no. 24 (November 15, 2017): 3489–99. http://dx.doi.org/10.1091/mbc.e17-04-0239.

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Mitoribosomes perform the synthesis of the core components of the oxidative phosphorylation (OXPHOS) system encoded by the mitochondrial genome. We provide evidence that MrpL35 (mL38), a mitospecific component of the yeast mitoribosomal central protuberance, assembles into a subcomplex with MrpL7 (uL5), Mrp7 (bL27), and MrpL36 (bL31) and mitospecific proteins MrpL17 (mL46) and MrpL28 (mL40). We isolated respiratory defective mrpL35 mutant yeast strains, which do not display an overall inhibition in mitochondrial protein synthesis but rather have a problem in cytochrome c oxidase complex (COX) assembly. Our findings indicate that MrpL35, with its partner Mrp7, play a key role in coordinating the synthesis of the Cox1 subunit with its assembly into the COX enzyme and in a manner that involves the Cox14 and Coa3 proteins. We propose that MrpL35 and Mrp7 are regulatory subunits of the mitoribosome acting to coordinate protein synthesis and OXPHOS assembly events and thus the bioenergetic capacity of the mitochondria.

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Timón-Gómez, Alba, Emma L. Bartley-Dier, Flavia Fontanesi, and Antoni Barrientos. "HIGD-Driven Regulation of Cytochrome c Oxidase Biogenesis and Function." Cells 9, no. 12 (December 6, 2020): 2620. http://dx.doi.org/10.3390/cells9122620.

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The biogenesis and function of eukaryotic cytochrome c oxidase or mitochondrial respiratory chain complex IV (CIV) undergo several levels of regulation to adapt to changing environmental conditions. Adaptation to hypoxia and oxidative stress involves CIV subunit isoform switch, changes in phosphorylation status, and modulation of CIV assembly and enzymatic activity by interacting factors. The latter include the Hypoxia Inducible Gene Domain (HIGD) family yeast respiratory supercomplex factors 1 and 2 (Rcf1 and Rcf2) and two mammalian homologs of Rcf1, the proteins HIGD1A and HIGD2A. Whereas Rcf1 and Rcf2 are expressed constitutively, expression of HIGD1A and HIGD2A is induced under stress conditions, such as hypoxia and/or low glucose levels. In both systems, the HIGD proteins localize in the mitochondrial inner membrane and play a role in the biogenesis of CIV as a free unit or as part as respiratory supercomplexes. Notably, they remain bound to assembled CIV and, by modulating its activity, regulate cellular respiration. Here, we will describe the current knowledge regarding the specific and overlapping roles of the several HIGD proteins in physiological and stress conditions.

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Khalimonchuk, Oleh, Kevin Rigby, Megan Bestwick, Fabien Pierrel, Paul A. Cobine, and Dennis R. Winge. "Pet191 Is a Cytochrome c Oxidase Assembly Factor in Saccharomyces cerevisiae." Eukaryotic Cell 7, no. 8 (May 23, 2008): 1427–31. http://dx.doi.org/10.1128/ec.00132-08.

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ABSTRACT The twin-Cx9C motif protein Pet191 is essential for cytochrome c oxidase maturation. The motif Cys residues are functionally important and appear to be present in disulfide linkages within a large oligomeric complex associated with the mitochondrial inner membrane. The import of Pet191 differs from that of other twin-Cx9C motif class of proteins in being independent of the Mia40 pathway.

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31

Llases, María-Eugenia, Marcos N. Morgada, and Alejandro J. Vila. "Biochemistry of Copper Site Assembly in Heme-Copper Oxidases: A Theme with Variations." International Journal of Molecular Sciences 20, no. 15 (August 5, 2019): 3830. http://dx.doi.org/10.3390/ijms20153830.

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Copper is an essential cofactor for aerobic respiration, since it is required as a redox cofactor in Cytochrome c Oxidase (COX). This ancient and highly conserved enzymatic complex from the family of heme-copper oxidase possesses two copper sites: CuA and CuB. Biosynthesis of the oxidase is a complex, stepwise process that requires a high number of assembly factors. In this review, we summarize the state-of-the-art in the assembly of COX, with special emphasis in the assembly of copper sites. Assembly of the CuA site is better understood, being at the same time highly variable among organisms. We also discuss the current challenges that prevent the full comprehension of the mechanisms of assembly and the pending issues in the field.

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Dennerlein, S., and P. Rehling. "Human mitochondrial COX1 assembly into cytochrome c oxidase at a glance." Journal of Cell Science 128, no. 5 (February 6, 2015): 833–37. http://dx.doi.org/10.1242/jcs.161729.

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Stiburek, Lukas, and Jiri Zeman. "Assembly factors and ATP-dependent proteases in cytochrome c oxidase biogenesis." Biochimica et Biophysica Acta (BBA) - Bioenergetics 1797, no. 6-7 (June 2010): 1149–58. http://dx.doi.org/10.1016/j.bbabio.2010.04.006.

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Alles, M., and B. Ludwig. "Mechanism of CuA assembly in the biogenesis of cytochrome c oxidase." Biochimica et Biophysica Acta (BBA) - Bioenergetics 1817 (October 2012): S66—S67. http://dx.doi.org/10.1016/j.bbabio.2012.06.189.

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35

Broadley, Sarah A., Christina M. Demlow, and Thomas D. Fox. "Peripheral Mitochondrial Inner Membrane Protein, Mss2p, Required for Export of the Mitochondrially Coded Cox2p C Tail inSaccharomyces cerevisiae." Molecular and Cellular Biology 21, no. 22 (November 15, 2001): 7663–72. http://dx.doi.org/10.1128/mcb.21.22.7663-7672.2001.

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ABSTRACT Cytochrome oxidase subunit 2 (Cox2p) is synthesized on the matrix side of the mitochondrial inner membrane, and its N- and C-terminal domains are exported across the inner membrane by distinct mechanisms. The Saccharomyces cerevisiaenuclear gene MSS2 was previously shown to be necessary for Cox2p accumulation. We have used pulse-labeling studies and the expression of the ARG8 m reporter at the COX2 locus in an mss2 mutant to demonstrate that Mss2p is not required for Cox2p synthesis but rather for its accumulation. Mutational inactivation of the proteolytic function of the matrix-localized Yta10p (Afg3p) AAA-protease partially stabilizes Cox2p in an mss2 mutant but does not restore assembly of cytochrome oxidase. In the absence of Mss2p, the Cox2p N terminus is exported, but Cox2p C-terminal export and assembly of Cox2p into cytochrome oxidase is blocked. Epitope-tagged Mss2p is tightly, but peripherally, associated with the inner membrane and protected by it from externally added proteases. Taken together, these data indicate that Mss2p plays a role in recognizing the Cox2p C tail in the matrix and promoting its export.

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36

Trueblood, C. E., R. M. Wright, and R. O. Poyton. "Differential regulation of the two genes encoding Saccharomyces cerevisiae cytochrome c oxidase subunit V by heme and the HAP2 and REO1 genes." Molecular and Cellular Biology 8, no. 10 (October 1988): 4537–40. http://dx.doi.org/10.1128/mcb.8.10.4537.

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In Saccharomyces cerevisiae, the COX5a and COX5b genes encode two forms of cytochrome c oxidase subunit V, Va and Vb. We report here that heme increases COX5a expression and decreases COX5b expression and that the HAP2 and REO1 genes are involved in positive regulation of COX5a and negative regulation of COX5b, respectively. Heme regulation of COX5a and COX5b may dictate which subunit V isoform is available for assembly into cytochrome c oxidase under conditions of high- and low-oxygen tension.

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Trueblood, C. E., R. M. Wright, and R. O. Poyton. "Differential regulation of the two genes encoding Saccharomyces cerevisiae cytochrome c oxidase subunit V by heme and the HAP2 and REO1 genes." Molecular and Cellular Biology 8, no. 10 (October 1988): 4537–40. http://dx.doi.org/10.1128/mcb.8.10.4537-4540.1988.

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In Saccharomyces cerevisiae, the COX5a and COX5b genes encode two forms of cytochrome c oxidase subunit V, Va and Vb. We report here that heme increases COX5a expression and decreases COX5b expression and that the HAP2 and REO1 genes are involved in positive regulation of COX5a and negative regulation of COX5b, respectively. Heme regulation of COX5a and COX5b may dictate which subunit V isoform is available for assembly into cytochrome c oxidase under conditions of high- and low-oxygen tension.

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38

Koch, Hans-Georg, Olivia Hwang, and Fevzi Daldal. "Isolation and Characterization of Rhodobacter capsulatus Mutants Affected in Cytochromecbb3 Oxidase Activity." Journal of Bacteriology 180, no. 4 (February 15, 1998): 969–78. http://dx.doi.org/10.1128/jb.180.4.969-978.1998.

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ABSTRACT The facultative phototrophic bacterium Rhodobacter capsulatus contains only one form of cytochrome (cyt)c oxidase, which has recently been identified as acbb3 -type cyt c oxidase. This is unlike other related species, such as Rhodobacter sphaeroides and Paracoccus denitrificans, which contain an additional mitochondrial-likeaa 3-type cyt c oxidase. An extensive search for mutants affected in cyt c oxidase activity in R. capsulatus led to the isolation of at least five classes of mutants. Plasmids complementing them to a wild-type phenotype were obtained for all but one of these classes from a chromosomal DNA library. The first class of mutants contained mutations within the structural genes (ccoNOQP) of the cytcbb 3 oxidase. Sequence analysis of these mutants and of the plasmids complementing them revealed thatccoNOQP in R. capsulatus is not flanked by the oxygen response regulator fnr, which is located upstream of these genes in other species. Genetic and biochemical characterizations of mutants belonging to this group indicated that the subunits CcoN, CcoO, and CcoP are required for the presence of an active cytcbb 3 oxidase, and unlike inBradyrhizobium japonicum, no active CcoN-CcoO subcomplex was found in R. capsulatus. In addition, mutagenesis experiments indicated that the highly conserved open reading frame 277 located adjacent to ccoNOQP is required neither for cytcbb 3 oxidase activity or assembly nor for respiratory or photosynthetic energy transduction in R. capsulatus. The remaining cyt c oxidase-minus mutants mapped outside of ccoNOQP and formed four additional groups. In one of these groups, a fully assembled but inactive cytcbb 3 oxidase was found, while another group had only extremely small amounts of it. The next group was characterized by a pleiotropic effect on all membrane-bound c-type cytochromes, and the remaining mutants not complemented by the plasmids complementing the first four groups formed at least one additional group affecting the biogenesis of the cyt cbb 3oxidase of R. capsulatus.

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Cooper, Chris E., Peter Nicholls, and Jo A. Freedman. "Cytochrome c oxidase: structure, function, and membrane topology of the polypeptide subunits." Biochemistry and Cell Biology 69, no. 9 (September 1, 1991): 586–607. http://dx.doi.org/10.1139/o91-089.

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Mitochondrial cytochrome c oxidase and its bacterial homologs catalyze electron transfer and proton translocation reactions across membranes. The eukaryotic enzyme complex consists of a large number of polypeptide subunits. Three of the subunits (I, II, and III) are mitochondrially encoded while the remaining 6 (yeast) to 10 (bovine) are nuclear encoded. Antibody and chemical-labelling experiments suggest that subunits I–III and most (but not all) of the nuclear-encoded subunits span the inner mitochondrial membrane. Subunits I and II are the catalytic core of the enzyme. Subunit I contains haem a, haem a3 and CuB, while subunit II contains CuA and the cytochrome c binding site. Subunit III and most of the nuclear subunits are essential for the assembly of a functional catalytic enzyme. Some nuclear subunits are present as isozymes, although little functional difference has yet been detected between enzyme complexes composed of different isozymes. Therefore, any additional role attributed to the nuclear-encoded subunits beyond that of enzyme assembly must be tentative. We suggest that enough evidence exists to support the idea that modification of the larger nuclear subunits (IV, V, and possibly VI) can affect enzyme turnover in vitro. Whether this is a physiological control mechanism remains to be seen.Key words: cytochrome oxidase, polypeptide subunits, antibodies, membrane protein, orientation.

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Kulajta, Carmen, Jörg Oliver Thumfart, Sybille Haid, Fevzi Daldal, and Hans-Georg Koch. "Multi-step Assembly Pathway of the cbb3-type Cytochrome c Oxidase Complex." Journal of Molecular Biology 355, no. 5 (February 2006): 989–1004. http://dx.doi.org/10.1016/j.jmb.2005.11.039.

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Dubinski, Alicia F., Raffaele Camasta, Tyler G. B. Soule, Bruce H. Reed, and D. Moira Glerum. "Consequences of cytochrome c oxidase assembly defects for the yeast stationary phase." Biochimica et Biophysica Acta (BBA) - Bioenergetics 1859, no. 6 (June 2018): 445–58. http://dx.doi.org/10.1016/j.bbabio.2018.03.011.

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42

Sacconi, Sabrina, Eva Trevisson, Francesca Pistollato, Maria Cristina Baldoin, Roger Rezzonico, Isabelle Bourget, Claude Desnuelle, et al. "hCOX18 and hCOX19: Two human genes involved in cytochrome c oxidase assembly." Biochemical and Biophysical Research Communications 337, no. 3 (November 2005): 832–39. http://dx.doi.org/10.1016/j.bbrc.2005.09.127.

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43

Sarti, P., G. Antonini, F. Malatesta, B. Vallone, M. Brunori, M. Masserini, P. Palestini, and G. Tettamanti. "Effect of gangliosides on membrane permeability studied by enzymic and fluorescence-spectroscopy techniques." Biochemical Journal 267, no. 2 (April 15, 1990): 413–16. http://dx.doi.org/10.1042/bj2670413.

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The effect of gangliosides on membrane permeability was investigated by studying the kinetic properties of cytochrome c oxidase, the activity of which, when the enzyme is reconstituted in phospholipid vesicles, is dependent on membrane permeability to H+ and K+. The experiments indicate that three different gangliosides (GM1, DD1a, GT1b) incorporated into cytochrome c oxidase-containing phospholipid vesicles stimulate enzymic activity, in the absence of ionophores, most probably by disorganizing the bilayer lipid assembly and increasing its permeability to ions. This interpretation was confirmed by fluorescence-spectroscopy experiments in which the rate of passive leakage of carboxyfluorescein entrapped in the vesicles was measured. Cholera toxin, or its isolated B-subunit, added to GM1-containing proteoliposomes inhibited cytochrome c oxidase activity, indicating the lack of formation, under these experimental conditions, of channels freely permeable to H+ or K+.

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44

Piccoli, Claudia, Rosella Scrima, Domenico Boffoli, and Nazzareno Capitanio. "Control by cytochrome c oxidase of the cellular oxidative phosphorylation system depends on the mitochondrial energy state." Biochemical Journal 396, no. 3 (May 29, 2006): 573–83. http://dx.doi.org/10.1042/bj20060077.

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Recent measurements of the flux control exerted by cytochrome c oxidase on the respiratory activity in intact cells have led to a re-appraisal of its regulatory function. We have further extended this in vivo study in the framework of the Metabolic Control Analysis and evaluated the impact of the mitochondrial transmembrane electrochemical potential (ΔμH+) on the control strength of the oxidase. The results indicate that, under conditions mimicking the mitochondrial State 4 of respiration, both the flux control coefficient and the threshold value of cytochrome oxidase are modified with respect to the uncoupled condition. The results obtained are consistent with a model based on changes in the assembly state of the oxidative phosphorylation enzyme complexes and possible implications in the understanding of exercise-intolerance of human neuromuscular degenerative diseases are discussed.

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Khalimonchuk, Oleh, Megan Bestwick, Brigitte Meunier, Talina C. Watts, and Dennis R. Winge. "Formation of the Redox Cofactor Centers during Cox1 Maturation in Yeast Cytochrome Oxidase." Molecular and Cellular Biology 30, no. 4 (December 7, 2009): 1004–17. http://dx.doi.org/10.1128/mcb.00640-09.

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ABSTRACT The biogenesis of cytochrome c oxidase initiates with synthesis and maturation of the mitochondrion-encoded Cox1 subunit prior to the addition of other subunits. Cox1 contains redox cofactors, including the low-spin heme a center and the heterobimetallic heme a 3:CuB center. We sought to identify the step in the maturation of Cox1 in which the redox cofactor centers are assembled. Newly synthesized Cox1 is incorporated within one early assembly intermediate containing Mss51 in Saccharomyces cerevisiae. Subsequent Cox1 maturation involves the progression to downstream assembly intermediates involving Coa1 and Shy1. We show that the two heme a cofactor sites in Cox1 form downstream of Mss51- and Coa1-containing Cox1 intermediates. These Cox1 intermediates form normally in cells defective in heme a biosynthesis or in cox1 mutant strains with heme a axial His mutations. In contrast, the Shy1-containing Cox1 assembly intermediate is perturbed in the absence of heme a. Heme a 3 center formation in Cox1 appears to be chaperoned by Shy1. CuB site formation occurs near or at the Shy1-containing Cox1 assembly intermediate also. The CuB metallochaperone Cox11 transiently interacts with Shy1 by coimmunoprecipitation. The Shy1-containing Cox1 complex is markedly attenuated in cells lacking Cox11 but is partially restored with a nonfunctional Cox11 mutant. Thus, formation of the heterobimetallic CuB:heme a 3 site likely occurs in the Shy1-containing Cox1 complex.

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Böttinger, Lena, Christoph U. Mårtensson, Jiyao Song, Nicole Zufall, Nils Wiedemann, and Thomas Becker. "Respiratory chain supercomplexes associate with the cysteine desulfurase complex of the iron–sulfur cluster assembly machinery." Molecular Biology of the Cell 29, no. 7 (April 2018): 776–85. http://dx.doi.org/10.1091/mbc.e17-09-0555.

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Mitochondria are the powerhouses of eukaryotic cells. The activity of the respiratory chain complexes generates a proton gradient across the inner membrane, which is used by the F1FO-ATP synthase to produce ATP for cellular metabolism. In baker’s yeast, Saccharomyces cerevisiae, the cytochrome bc1 complex (complex III) and cytochrome c oxidase (complex IV) associate in respiratory chain supercomplexes. Iron–sulfur clusters (ISC) form reactive centers of respiratory chain complexes. The assembly of ISC occurs in the mitochondrial matrix and is essential for cell viability. The cysteine desulfurase Nfs1 provides sulfur for ISC assembly and forms with partner proteins the ISC-biogenesis desulfurase complex (ISD complex). Here, we report an unexpected interaction of the active ISD complex with the cytochrome bc1 complex and cytochrome c oxidase. The individual deletion of complex III or complex IV blocks the association of the ISD complex with respiratory chain components. We conclude that the ISD complex binds selectively to respiratory chain supercomplexes. We propose that this molecular link contributes to coordination of iron–sulfur cluster formation with respiratory activity.

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Radford, Nina B., Bang Wan, Angela Richman, Lidia S. Szczepaniak, Jia-Ling Li, Kang Li, Kathy Pfeiffer, Hermann Schägger, Daniel J. Garry, and Randall W. Moreadith. "Cardiac dysfunction in mice lacking cytochrome-c oxidase subunit VIaH." American Journal of Physiology-Heart and Circulatory Physiology 282, no. 2 (February 1, 2002): H726—H733. http://dx.doi.org/10.1152/ajpheart.00308.2001.

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Cytochrome -c oxidase subunit VIaH (COXVIaH) has been implicated in the modulation of COX activity. A gene-targeting strategy was undertaken to generate mice that lacked COXVIaH to determine its role in regulation of oxidative energy production and mechanical performance in cardiac muscle. Total COX activity was decreased in hearts from mutant mice, which appears to be a consequence of altered assembly of the holoenzyme COX. However, total myocardial ATP was not significantly different in wild-type and mutant mice. Myocardial performance was examined using the isolated working heart preparation. As left atrial filling pressure increased, hearts from mutant mice were unable to generate equivalent stroke work compared with hearts from wild-type mice. Direct measurement of left ventricular end-diastolic volume using magnetic resonance imaging revealed that cardiac dysfunction was a consequence of impaired ventricular filling or diastolic dysfunction. These findings suggest that a genetic deficiency of COXVIaH has a measurable impact on myocardial diastolic performance despite the presence of normal cellular ATP levels.

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Mansilla, Natanael, Elina Welchen, and Daniel H. Gonzalez. "Arabidopsis SCO Proteins Oppositely Influence Cytochrome c Oxidase Levels and Gene Expression during Salinity Stress." Plant and Cell Physiology 60, no. 12 (August 16, 2019): 2769–84. http://dx.doi.org/10.1093/pcp/pcz166.

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Abstract SCO (synthesis of cytochrome c oxidase) proteins are involved in the insertion of copper during the assembly of cytochrome c oxidase (COX), the final enzyme of the mitochondrial respiratory chain. Two SCO proteins, namely, homolog of copper chaperone 1 and 2 (HCC1 and HCC2) are present in seed plants, but HCC2 lacks the residues involved in copper binding, leading to uncertainties about its function. In this study, we performed a transcriptomic and phenotypic analysis of Arabidopsis thaliana plants with reduced expression of HCC1 or HCC2. We observed that a deficiency in HCC1 causes a decrease in the expression of several stress-responsive genes, both under basal growth conditions and after applying a short-term high salinity treatment. In addition, HCC1 deficient plants show a faster decrease in chlorophyll content, photosystem II quantum efficiency and COX levels after salinity stress, as well as a faster increase in alternative oxidase capacity. Notably, HCC2 deficiency causes opposite changes in most of these parameters. Bimolecular fluorescence complementation analysis indicated that both proteins are able to interact. We postulate that HCC1 is a limiting factor for COX assembly during high salinity conditions and that HCC2 probably acts as a negative modulator of HCC1 activity through protein–protein interactions. In addition, a direct or indirect role of HCC1 and HCC2 in the gene expression response to stress is proposed.

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Lee, Sonny C., and R. H. Holm. "A synthetic analog of the iron/copper bridged assembly in cytochrome c oxidase." Journal of the American Chemical Society 115, no. 13 (June 1993): 5833–34. http://dx.doi.org/10.1021/ja00066a065.

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Oswald, C., U. Krause-Buchholz, and G. Rödel. "Knockdown of Human COX17 Affects Assembly and Supramolecular Organization of Cytochrome c Oxidase." Journal of Molecular Biology 389, no. 3 (June 2009): 470–79. http://dx.doi.org/10.1016/j.jmb.2009.04.034.

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Journal articles on the topic 'Assembly of cytochrom c oxidase'

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