Dissertations / Theses: 'Cytochrome c Oxidase sunbunit I'

1

Howell, T. W. "Reconstituted cytochrome c oxidase vesicles." Thesis, University of Bristol, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370702.

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2

Cappuccio, Jenny A. "Spectroscopic studies of cytochrome c oxidase /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2004. http://uclibs.org/PID/11984.

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3

Lin, Jian Chan Sunney I. "ATP modulation of the electron transfer between cytochrome c and cytochrome c oxidase." Diss., Pasadena, Calif. : California Institute of Technology, 1995. http://resolver.caltech.edu/CaltechETD:etd-10182007-085924.

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4

Brändén, Gisela. "Structure and function of cytochrome c oxidase /." Stockholm : Department of Biochemistry and Biophysics, Stockholm University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1226.

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5

Poynter, D. "Structural studies on bovine heart cytochrome c oxidase." Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356539.

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6

Chrzanowska-Lightowlers, Zofia Maria Alexandra. "Regulation of the homeostasis of cytochrome C oxidase." Thesis, University of Newcastle Upon Tyne, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260970.

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7

Adams, Paula Louise. "Cytochrome c oxidase deficiency : biochemical & molecular studies." Thesis, University of Newcastle Upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337193.

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8

Näsvik, Öjemyr Linda. "Membrane effects on proton transfer in cytochrome c oxidase." Doctoral thesis, Stockholms universitet, Institutionen för biokemi och biofysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-75633.

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The biological membrane is composed of lipids and proteins that make up dynamic barriers around cells and organelles. Membrane-spanning proteins are involved in many key processes in the cell such as energy conversion, nerve conduction and signal transduction. These proteins interact closely with lipids as well as with other proteins in the membrane, which modulates and affects their structure and function. In the energy-conversion process, membrane-bound proton-transport proteins maintain an electrochemical proton gradient across the mitochondrial inner membrane or the cytoplasmic membrane of bacteria. This gradient is utilized for ATP synthesis or transport of ions and molecules across the membrane. Results from earlier studies have shown that proton transporters are influenced by their environment. Here, one of these proton transporters, cytochrome c oxidase, has been purified and reconstituted into liposomes or nanodiscs and membrane effects on specific proton-transfer processes were studied. In these studies we observed that the membrane accelerated proton transfer to the surface of cytochrome c oxidase and that there is a protonic link, via a Glu residue that mediates proton transfer from the membrane surface to a proton-transfer pathway in this protein. In addition, the membrane was shown to modulate specific internal electron and proton-transfer reactions. The results from these studies show that the membrane composition influences transmembrane transport. Consequently, our understanding of these processes requires investigation of these transporter proteins in different membrane-mimetic systems of variable and well-defined composition. Furthermore, the data show that membrane surfaces facilitate lateral proton transfer which is presumably essential for maintaining high efficiency in energy conversion. This is particular important in organisms such as alkaliphilic bacteria where the driving force of the electrochemical proton gradient, between the bulk solution on each side of the membrane is not sufficient for ATP synthesis.

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9

Salomonsson, Lina. "Proton, Electron, and O₂ transfer in Cytochrome c Oxidase /." Stockholm : Department of Biochemistry and Biophysics, Stockholm university, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1222.

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10

El-Agez, Bassam Ali. "A kinetic and spectroscopic study on cytochrome c oxidase." Thesis, University of Essex, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305116.

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11

Namslauer, Ida. "Cytochrome c Oxidase dysfunction in cancer : Exploring the molecular mechanisms." Doctoral thesis, Stockholms universitet, Institutionen för biokemi och biofysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-65303.

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Mutations in genes encoding the mitochondrial enzyme Cytochrome c Oxidase (CytcO) have lately been found in connection to various types of cancer. Some mutations result in substitutions of highly conserved amino-acid residues. As CytcO is an essential enzyme in oxidative phosphorylation, the substitutions are likely to have deleterious effects on the cellular energy metabolism. There is, however, a lack of data on the functional consequences of the pathogenic substitutions. In the publications on which this thesis is based, we investigated the effects of the substitutions on a molecular level. This was done using the validated bacterial model organism Rhodobacter sphaeroides which has a CytcO that is both structurally and functionally similar to the mammalian CytcO. For the functional studies, we used spectroscopic techniques to investigate the overall activity of the enzyme as well as the proton-pumping efficiency and the internal proton and electron transfers. We found that most of the CytcO substitutions observed in connection to cancer, resulted in a decreased catalytic activity. The impaired activity was due to defects in specific electron- or proton-transfer processes. Moreover, in several cases the substitutions resulted in an impaired proton-pumping activity. This thesis deals with the relevance of using R. sphaeroides CytcO as a model system for investigating human disease, as well as the possible links between the defective enzyme and the development of cancer.

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12

Stanley, Brian Allan. "Characterization of cytochrome c oxidase subunit II from Bacillus subtilis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63372.pdf.

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13

Alleyne, T. A. "A study of the conformational transitions of cytochrome c oxidase." Thesis, University of Essex, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235259.

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14

Kim, Sun Hee. "Advanced EPR studies of photosystem II and cytochrome c oxidase /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.

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15

Ädelroth, Pia. "Mechanisms and pathways for proton transfer in cytochrome-c oxidase." Göteborg : Göteborg University, 1998. http://catalog.hathitrust.org/api/volumes/oclc/68945135.html.

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16

Auclair, Benoît. "Thermosensibilité des propriétés fonctionnelles du complexe cytochrome c oxidase-cytochrome c et coévalution des génomes mitochondrial et nucléaire." Thèse, [Rimouski, Québec] : Université du Québec à Rimouski, 2005.

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Thèse (M. Sc.) - Université du Québec à Rimouski, 2005.
Titre de lʹécran-titre (visionné le 31 août 2006). Mémoire présenté à l'Université du Québec à Rimouski comme exigence partielle du programme de maîtrise en gestion de la faune et de ses habitats. CaQRU CaQRU Bibliogr.: f. 55-59. Paraît aussi en éd. imprimée. CaQRU

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17

Paret, Claudia. "Assembly of cytochrome c oxidase: the role of hSco1p and hSco2p." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2001. http://nbn-resolving.de/urn:nbn:de:swb:14-1008679017468-62905.

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COX deficiency in human presents a plethora of phenotypes which is not surprising given the complexity of the enzyme structure and the multiple factors and many steps required for its assembly. A functional COX requires three mitochondrially encoded subunits (Cox1p, Cox2p and Cox3p), at least 10 nuclearly encoded subunits, some of which are tissue specific, and a yet unknown number of assembly factors. Mutations in four of these factors, hSco1p, hSco2p, hCox10p and hSurf1p, have been associated with lethal COX deficiency in patients. Sco proteins, conserved from prokaryotes to eukaryotes, are probably involved in the insertion of copper in COX. The role of hSco1p and hSco2p in this process was investigated in this work. Moreover the importance of some hSco mutations found in patients was analysed. Both in vitro and in vivo analyses show that the hSco proteins are localised in the mitochondria. Both proteins are per se unable to substitute for ySco1p. However, a chimeric construct consisting of the N-terminal portion, the TM and a part of the C-terminal portion of ySco1p and the remaining C-terminal part derived from hSco1p was able to complement a ysco1 null mutant strain. This construct was used to define the role of a point mutation (P174L) found in the hSCO1 gene of infants suffering from ketoacidotic coma. These mutation was shown to affect the COX activity and the levels of Cox1p and Cox2p. The fact that copper was able to suppress this mutation, strongly outlined the importance of Sco proteins in the copper insertion in COX. The C-terminal portions of recombinant hSco1p and hSco2p were purified from E. coli by affinity chromatography. The purified proteins were subjected to atomic emission and absorption analyses and were shown to specifically bind copper. A stoichiometry of 1:1 for hSco2p and of 0,6:1 for hSco1p was determined. To identify the Aa residues involved in copper binding, in vitro mutagenesis was performed. hSco1p and hSco2p, lacking the cysteines of the predicted metal binding site CxxxC, show a dramatic decrease in the ability to bind copper. A model for the structure of the metal binding site in hSco proteins is proposed. hSco proteins could bind copper with trigonal coordination, involving the two cysteines of the CxxxC motif and a conserved histidine. The purified recombinant proteins were also used in an enzymatic assay to test their ability to reduce disulfide bridges, similar to thioredoxin-like proteins involved in the assembly of bacterial COX. Both hSco proteins were not able to act as thioredoxins suggesting a role for the hSco proteins as copper chaperones. To define the pathway of the copper transfer to COX, hSco proteins were tested for their ability to interact with hCox17p, a mitochondrial copper chaperone, and with Cox2p, which contains two copper ions. An interaction between hSco1p and Cox2p was detected. Both hSco proteins were shown to homomerise and to form heterodimers one with each other. Two mutations found in hSCO2 patients suffering from hypertrophic cardiomyopathy, (E140K and S225F) were shown not to affect the copper binding properties, the intracellular localisation and the ability to form homomers. In accordance to these data, a model is proposed in which hSco2p dimers transfer copper to hSco1p dimers. hSco1p dimers interact with COX and insert copper in the binuclear centre of Cox2p.

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18

Williams, Sion Llewelyn. "Aspects of the biogenesis of cytochrome c oxidase in human cells." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1446910/.

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Cytochrome c oxidase (COX) is a component of the mitochondrial oxidative phosphorylation system (OXPHOS) which is the principal source of ATP for the majority of human tissues. The COX holo-complex is a homodimer of 13 different subunits, encoded by both the nuclear and mitochondrial genomes (mtDNA), and contains metal ions and haem A prosthetic groups. Disrupted biogenesis of the holo-complex is the most common cause of COX deficiency. As genetic manipulation of human cells is difficult, cells derived from patients with COX deficiency provide a valuable resource for improving our understanding of COX biogenesis and COX deficiency. This thesis is a comparative study of COX deficient fibroblasts derived from seven patients with mitochondrial disorders of undetermined genetic origin, normal controls and disease controls carrying mutations in mitochondrial tRNA genes or the COX assembly factors SCO1 and COX10. The project was designed to answer two questions: What are the molecular mechanisms behind the enzyme deficiency in the patient cells What can this tell us about the biogenesis of the COX holo-complex Phenotyping of the cultures revealed distinct patterns of OXPHOS subunit expression and confirmed that the COX defects were caused by disrupted biogenesis of the holo-complex. Genotyping excluded the involvement of mtDNA and sequencing of the COX assembly factor SURF1 identified mutations in four of the patients. Blue-native polyacrylamide gel electrophoresis found that COX sub-complexes, which resembled known assembly intermediates, accumulated in SURF1 and SCO1 mutant cells but not those with COX10 mutations. This suggests that SURF1 and SCO1 function at a similar point in COX biogenesis and supports the view that COX10 functions early in COX assembly. The results are discussed in the context of our current understanding of COX biogenesis and the causes of COX deficiency with emphasis on the molecular pathology of SURF1 mutant cells.

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19

Hartlen, Rebecca. "Expression of cytochrome c oxidase subunit II from a nuclear transgene." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0024/MQ50783.pdf.

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20

Leary, Scot C. "Interactions between bioenergetics and cytochrome c oxidase levels in striated muscles." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ63432.pdf.

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21

Lopez, Garcia Roberto. "Bio-mimetic analogues of the active site in cytochrome C oxidase." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416397.

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22

Preiss, Thomas. "Cytochrome c oxidase : a model system for post-transcriptional gene regulation." Thesis, University of Newcastle Upon Tyne, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281705.

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23

Abubakar, Mohammed Kaoje. "Studies of the structural and functional dynamics of cytochrome c oxidase." Thesis, University of Essex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241211.

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24

Xu, Shujuan. "EPR studies of electron and proton transfer in cytochrome c oxidase." Diss., Connect to online resource - MSU authorized users, 2008.

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Thesis (Ph. D.)--Michigan State University. Chemistry, Biochemistry and Molecular Biology, 2008.
Title from PDF t.p. (viewed on July 2, 2009) Includes bibliographical references. Also issued in print.

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25

Li, Peter Mark Chan Sunney I. "The role of CuA in the cytochrome c oxidase proton pump /." Diss., Pasadena, Calif. : California Institute of Technology, 1990. http://resolver.caltech.edu/CaltechETD:etd-06202007-085253.

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26

He, Qizhi Chan Sunney I. Chan Sunney I. "Cytochrome c oxidase : studies of electron input and intramolecular electron transfer /." Diss., Pasadena, Calif. : California Institute of Technology, 1995. http://resolver.caltech.edu/CaltechETD:etd-10052007-085601.

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27

Baden, Katrina Nicolle. "The effects of cytochrome c oxidase deficiency on early development in Danio rerio : a multilevel analysis of pathology /." view abstract or download file of text, 2007. http://proquest.umi.com/pqdweb?did=1417800921&sid=5&Fmt=2&clientId=11238&RQT=309&VName=PQD.

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Thesis (Ph. D.)--University of Oregon, 2007.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 70-82). Also available for download via the World Wide Web; free to University of Oregon users.

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28

Lee, Sang Tae Chemistry Faculty of Science UNSW. "Model studies of the cub-histidine-tyrosine centre in cytochrome c oxidase." Awarded by:University of New South Wales. Chemistry, 2005. http://handle.unsw.edu.au/1959.4/33251.

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This thesis reports the synthesis and copper coordination chemistry of covalently-linked aryl-imidazole derivatives designed as models for the crosslinked imidazole-phenol sidechains of the His-Tyr cofactor in the CcO. Three new imidazole- (HL1 - HL3) and three new indole- (HL4 - H2L6) containing tripodal ligands were synthesised. The conjugate addition of an imidazole to activated quinone derivatives was developed as a new route to organic models for the Tyr His cofactor. Two monodentate imidazole-aryl, Im-hq(OH)2 and Im-ArOH, and an imidazole-quinone, Im bq were obtained using this route. The X-ray crystal structure of Im-hq(OH)2.EtOH was determined. The route was also used to give new chelating ligands, H2L10 and HL12, containing a cross-linked imidazole-phenol surrogate for the Tyr244-His240 cofactor. Copper complexes of Im-hq(OH)2, Im-bq, Im-ArOH, H2L10-HL12, and HL1-H2L6 were prepared, and the X-ray crystal structures of [Cu(terpy)(Im-bq)][BF4]2 and five other copper complexes were determined. The physiochemical properties of the copper complexes were characterized by FT-IR, UV-Vis-NIR, EPR and (spectro)electrochemical studies. Key results include: the oxidation of Im-ArO- anion affords the semiquinone radical, Im-sq(4OH)(1O??????), in a hydrous solvent. However, the oxidations of neutral Im-ArOH and [Cu(tpa)(Im-ArOH)]2+ produce the corresponding phenoxy radical species that rapidly and reversibly dimerise to give quinol cyclohexadienone, QCHD, dimers. Significantly [Cu(tpa)(Im-sq(4OH)(1O??????))]2+ was EPR silent, perhaps due to antiferromagnetic coupling between the Cu(II) (S=1/2) and semiquinonyl radical (S=1/2) centres. Deprotonation of the hydroquinone in [Cu(tpa)(Im-hq(OH)2]2+ produces the hydroquinone dianion which reduces the Cu(II) centre. The semiquinone radical is coordinatively labile and dissociates from the Cu(I) centre. The biological implications of these results are mentioned.

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29

Weraarpachai, Woranontee. "Identification and characterization of novel genes involved in cytochrome c oxidase deficiencies." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107626.

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In mitochondria, ATP is generated by oxidative phosphorylation (OXPHOS), a process that requires five multimeric enzyme complexes. Electrons are passed along the first four enzyme complexes (complex I-IV) that make up the mitochondria respiratory chain, releasing energy that is stored in the form of a proton gradient across the mitochondrial inner membrane, and is subsequently used by the ATP synthase (complex V) to produce ATP. Complex IV or cytochrome c oxidase (COX) is the terminal enzyme in the mitochondrial respiratory chain, catalyzing the oxidation of cytochrome c by molecular oxygen. It contains 13 structural subunits in mammals, 3 of which are encoded by mitochondrial DNA. Cytochrome c oxidase deficiencies can be caused by mutations in either mitochondrial or nuclear DNA. COX deficiency can result from mutations in the structural subunits or factors necessary for the assembly of the enzyme complex. In this thesis, two novel genes mutated in two subjects with COX deficiency have been identified. First, we identified a specific defect in the synthesis of the mtDNA-encoded COX subunit 1 (COX I) in a pedigree segregating late-onset Leigh Syndrome and COX deficiency. We mapped the defect to chromosome 17q by microcell-mediated chromosome transfer and identified a homozygous single base pair insertion causing a premature stop in CCDC44, renamed TACO1 for translational activator of COX I. TACO1 is a member of a large family of hypothetical proteins containing a conserved DUF28 domain that localizes to the mitochondrial matrix. Expression of the wild-type cDNA restored TACO1 protein and rescued the translation defect. TACO1 is the first specific mitochondrial translational activator identified in mammals. Respiratory competence, mitochondrial translation and COX activity were normal in yeast strain deleted for the orthologue YGR021w, suggesting that TACO1 has evolved a novel function in mammalian mitochondrial translation. Secondly, we studied a family in which the subject presented with severe congenital lactic acidosis and dysmorphic features associated with a COX assembly defect and a specific decrease in the synthesis of COX I. Using a combination of microcell mediated chromosome transfer, homozygosity mapping, and transcript profiling we mapped the gene defect to chromosome 12, and identified a homozygous missense mutation causing an amino acid change from methionine to isoleucine in C12orf62, a gene apparently restricted to the vertebrate lineage. Expression of the wild-type cDNA restored C12orf62 protein levels, and rescued the COX I synthesis and COX assembly defect. C12orf62 is a very small (6 kDa), uncharacterized, single transmembrane protein that localizes to mitochondria. COX I, II and IV subunits co-immunoprecipitated with an epitope-tagged version of C12orf62, and 2D BN-PAGE analysis of newly synthesized mitochondrial COX subunits in subject fibroblasts showed that COX assembly was impaired, and the nascent enzyme complex unstable. We conclude that C12orf62 is required for coordinating the early steps of COX assembly with the synthesis of COX I.
Dans les mitochondries, l'ATP est généré par la phosphorylation oxydative (PHOSOX), un processus qui nécessite cinq complexes enzymatiques multimériques. Le transport des électrons le long des quatre premiers complexes enzymatiques (complexes I-IV) libère l'énergie qui est stockée sous la forme d'un gradient de protons à travers la membrane interne mitochondriale et est ensuite utilisée par l'ATP synthétase (complexe V) pour produire de l'ATP. Le complexe IV ou cytochrome C oxydase (COX) est l'enzyme terminale de la chaîne respiratoire mitochondriale, catalysant l'oxydation du cytochrome c par l'oxygène moléculaire. Il contient 13 sous-unités structurelles chez les mammifères, dont 3 sont codées par l'ADN mitochondriale. Les déficiences en cytochrome C oxydase peuvent être causées par des mutations dans l'ADN mitochondriale ou l'ADN nucléaire. Les carences en COX peuvent être liées à des mutations dans les sous-unités structurelles ou à des mutations dans des facteurs nécessaires à l'assemblage du complexe enzymatique. Dans cette thèse, deux nouveaux gènes mutés ont été identifiés et caractérisés dans deux patients présentant un déficit en COX. Premièrement, nous avons identifié un défaut spécifique dans la synthèse de la sous-unité COX 1 de l'ADN mitochondriale (COX I) dans un pedigree présentant une apparition tardive du syndrome de Leigh et une carence en COX. Nous avons cartographié le défaut génétique au chromosome 17q par la technique de transfert de chromosomes à médiation microcellulaire. Nous avons, par la suite, identifié une mutation homozygote, une insertion d'une base causant l'apparition prématurée d'un codon stop qui entraîne l'arrêt de la synthèse de la protéine CCDC44, renommé TACO1 pour activateur de la traduction de la COX I. TACO1 est membre d'une famille de protéines contenant un domaine conservé à fonction inconnue, nommé DUF28, qui se localise à la matrice mitochondriale. L'expression de l'ADN complémentaire de type sauvage de TACO1 compense le défaut de traduction de COX I. TACO1 est le premier activateur spécifique de la traduction mitochondriale à être identifié chez les mammifères. Il a été observé que l'absence (knock-down) du gène codant l'orthologue de TACO1 chez la levure, le YGR021w, ne perturbait pas la compétence des voies respiratoires, la traduction mitochondriale, ni l'activité de COX. Ceci suggère que TACO1 a évolué et a acquérit une nouvelle fonction dans la traduction mitochondriale chez les mammifères. Deuxièmement, nous avons étudié une famille dans laquelle le sujet présentait une acidose lactique congénitale et dysmorphie associée à un défaut d'assemblage et une diminution de l'activité enzymatique de la COX due à un défaut spécifique dans la traduction de COX I. En utilisant une combinaison de techniques dont le transfert de chromosomes à médiation microcellulaire, la cartographie d'homozygotie et le profilage de transcription, nous avons cartographié le gène défectueux sur le chromosome 12. Nous avons identifié une mutation faux sens à l'état homozygote provoquant un changement d'acide aminé de méthionine en isoleucine dans le gène C12orf62, un gène qui semble restreint à la lignée des vertébrés. L'expression de l'ADN complémentaire de type sauvage de C12orf62 a restauré la synthèse de COX I et le défaut d'assemblage de la COX. C12orf62 est une très petite protéine transmembranaire (6 kDa), non caractérisée, qui se localise aux mitochondries. Les sous-unités COX I, II et IV co-immunoprécipitent avec un épitope marqué de la protéine C12orf62. Les analyses de bleu d'électrophorèse sur gel de polyacrylamide natif (BN-PAGE) en deux dimensions pour les sous-unités nouvellement synthétisées de la COX mitochondriale ont démontré que la COX assemblée est altérée et que le complexe enzymatique naissant est instable dans les fibroblastes du patient atteint. Nous concluons que C12orf62 est nécessaire pour coordonner les étapes précoces de l'assemblage de la COX et de la synthèse de COX I.

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30

Lemma-Gray, Patrizia. "Structure-function relationships within cytochrome C oxidase and complex I a dissertation /." San Antonio : UTHSC, 2008. http://proquest.umi.com.libproxy.uthscsa.edu/pqdweb?did=1594481111&sid=12&Fmt=2&clientId=70986&RQT=309&VName=PQD.

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31

Pawlik, Grzegorz. "Assembly and maturation of cbb3-type cytochrome c oxidase in Rhodobacter capsulatus." Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAF070.

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Dans cette thèse, le processus d'assemblage ainsi que la maturation du cytochrome c oxydase de type cbb3 (cbb3-Cox) ont été étudiés dans la proteobactérie phototrophique pourpe non soufrée Rhodobacter capsulatus. R. capsulatus contient une chaîne de transfert d'électrons très ramifiée et represente un modèle d’organisme très utilisé dans l'étude des processus respiratoires et photosynthétiques.Les cbb3-Coxs spécifiques des bactéries représentent la deuxième catégorie la plus abondante des cytochromes c oxydases après le type Cox-aa3, mais n'ont jusqu'à présent pas été étudiées en détail. Récemment, la première structure cristalline cbb3-Cox de P. stutzeri a été obtenue, fournissant ainsi une avancée majeure invitant à des etudes plus détaillées sur le mécanisme catalytique et le processus d'assemblage. Les études sur les procédés d'assemblage et de maturation sont d'une très grande importance en raison du fait que de nombreux agents pathogènes humains tels que Helicobacter pylori, Neisseria meningitidis ou Campylobacter jejuni utilisent ce type de Cox, ce qui par conséquent pourrait amener a développer une interessante cible thérapeutique.Cbb3-Cox dans R. capsulatus est encodé par le gène opéron ccoNOQP codant quatre protéines membranaires constitutives de cbb3-Cox. CcoP et CcoO sont des cytochromes de type c, contenant des motifs périplasmiques fixés à l’hème. CcoN est la sous-unité centrale catalytique contenant deux molécules d’hèmes de type b et un ion cuivre. L’étude de la distribution de l’ion Cu à la sous-unité CcoN et l'assemblage des quatre sous-unités dans le complexe actif cbb3-Cox complexe sont les thèmes principaux de ce travail.Ici, le rôle du facteur d'assemblage putatif CcoH, sa structure et son interaction avec cbb3-Cox ont été étudiés en détail. CcoH est une petite protéine membranaire codé dans le groupe de gènes ccoGHIS situé à proximité des gènes codant cbb3-Cox. L'analyse in vivo de la formation de cbb3-Cox dans une souche ne contenant pas le facteur CcoH a montré une absence totale de cbb3-Cox. De même, la stabilité du facteur CcoH a été considérablement altérée dans une souche avec deletion du gene ccoNOQP. La dépendance mutuelle des deux protéines suggère leur interaction directe, ce qui a été confirmé par la photoréticulation directe de CcoH à la sous-unité CcoN, l’immunodétection de CcoH dans les cbb3-Cox complexes sur gels Blue Native, la co-purification par marquage CcoH-cbb3-Cox et le marquage radioactive in vitro des complexes cbb3-Cox avec CcoH.[...]
In this thesis, the assembly and maturation process of the cbb3-type cytochrome c oxidase (cbb3-Cox) was studied in the purple-non-sulphur phototrophic α-proteobacterium Rhodobacter capsulatus. R. capsulatus contains a highly branched electron-transfer chain and is a well studied model organism for investigating respiratory and photosynthetic processes.The bacteria-specific cbb3-Coxs represent the second most abundant class of cytochrome c oxidases after the aa3-type Cox, but have so far not been investigated in much detail. Recently, the first crystal structure of cbb3-Cox from P. stutzeri was obtained, providing a major breakthrough and inviting detailed studies on the catalytic mechanism and the assembly process. Studies on the assembly and maturation processes are of wide significance due to the fact that many human pathogens like Helicobacter pylori, Neisseria meningitides or Campylobacter jejuni use this type of Cox and it therefore might develop into an attractive drug-target. cbb3-Cox in R. capsulatus is encoded by the ccoNOQP gene operon which codes for four membrane proteins constituting cbb3-Cox. CcoP and CcoO are c-type cytochromes, containing periplasmic heme-binding motifs. CcoN is the central catalytic subunit which contains two b-type hemes and a copper ion. Investigating the delivery of Cu to the CcoN subunit and the assembly of all four subunits into the active cbb3-Cox complex were the main topics of this work. Here the role of the putative assembly factor CcoH, its structure and interaction with cbb3-Cox was investigated in detail. CcoH is a small membrane protein encoded in the ccoGHIS gene cluster located adjacent to the genes coding for cbb3-Cox. In vivo analysis of cbb3-Cox formation in a strain lacking ccoH showed the total absence of cbb3-Cox. Likewise, the stability of CcoH was drastically impaired in a ccoNOQP deletion strain. The mutual dependency of both proteins suggested their direct interaction, which was confirmed by site-directed photocrosslinking of CcoH to the CcoN subunit, by immunodetection of CcoH in cbb3-Cox complexes on Blue Native gels, by CcoH-cbb3-Cox co-purification and by in vitro labelling of cbb3-Cox complexes with radioactively labelled CcoH.[...]

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Horn, Darryl M. "Characterization of Two CX9C Containing Mitochondrial Proteins Necessary for Cytochrome c Oxidase Assembly." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/375.

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Copper is an essential cofactor of two mitochondrial enzymes: cytochrome c oxidase (COX) and the mitochondrial localized fraction of Cu-Zn superoxide dismutase (Sod1p). Copper incorporation into these enzymes is facilitated by a growing number of metallochaperone proteins. Here we describe two novel copper chaperones of COX, Cmc1 and Cmc2. In Saccharomyces cerevisiae, both Cmc1 and Cmc2 localize to the mitochondrial inner membrane facing the intermembrane space. Cmc1 and Cmc2 are essential for full expression of COX and cellular respiration, contain a twin Cx9C domain, and are conserved from yeast to humans. Additionally, the presence or absence of these proteins not only determines full assembly of functional COX but also affects metallation of Sod1 suggesting these proteins might play a role on co-modulation of copper transfer to COX and Sod1. CMC1 overexpression does not rescue the respiratory defect of cmc2 mutants or vise versa. However, Cmc2 physically interacts with Cmc1 and the absence of Cmc2 induces a 5-fold increase in Cmc1 accumulation in the mitochondrial membranes. We conclude that Cmc1 and Cmc2 have cooperative but non-overlapping functions in cytochrome c oxidase biogenesis.

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Bamji, Michelle. "Functional characterization of the human cytochrome c oxidase factor COX11 using RNA interference." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81591.

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Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, is composed of thirteen structural subunits, and requires the addition of several prosthetic groups including, copper and heme moieties, and magnesium and zinc ions. Deficiencies in the assembly of COX lead to several clinical phenotypes including Leigh syndrome and hypertrophic cardiomyopathy. In this study, RNA interference was used in a human cell line to stably knockdown the expression of COX11, a COX assembly factor thought to be involved in Cu B site metallation. These cells showed a reduction in both COX assembly and activity, which were suppressed by overexpression of COX17, but not by SCO1 or SCO2, two proteins involved in CUA metallation. These results support a model of two independent copper delivery pathways to COX, both of which require COX17 as a copper donor.

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Johansson, Ann-Louise. "Structural elements involved in protein-mediated proton transfer : Implications from studies of cytochrome c oxidase." Doctoral thesis, Stockholms universitet, Institutionen för biokemi och biofysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-85934.

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Proton transfer is one of the most common reactions in biological systems. During energy conversion inside a cell, proton transfer is crucial to maintain an electrochemical proton gradient across the cell membrane. This gradient is in turn used to e.g. produce ATP, the energy currency of the cell. One of the key components of the build-up of this gradient is cytochrome c oxidase. This membrane-bound enzyme catalyzes the reduction of molecular oxygen to water, using protons and electrons, and in the process protons are pumped across the membrane. All protons used during oxygen reduction and those that are pumped, are transferred via hydrophilic pathways inside the hydrophobic interior of the enzyme. One of these pathways, called the D pathway, is used to transfer protons both to the catalytic site and towards a pump site. It is yet not fully understood how these proton-transfer reactions are timed, coupled and controlled. This thesis is focused on studies of proton-transfer reactions through the D pathway in variants of cytochrome c oxidase that lack the ability to pump protons. The results suggest that changes in pKa values of key residues, as well as structural changes inside the pathway, can explain the non-pumping phenotypes. The results have led us to propose that an internal proton shuttle (Glu286I) can adopt two different conformations that are in equilibrium with each other, and that this equilibrium is altered in non-pumping variants of cytochrome c oxidase. We also observed that proton transfer through the D pathway could occur with the same rate as in the wild-type enzyme even when one of the key residues (Asp132I) is absent. This result contradicts previous assumptions that acidic residues must be present at an orifice of proton pathways. We therefore suggest that this specific residue could have an additional role, e.g. as a selectivity filter that excludes all ions except protons from entering the pathway.

At the time of doctoral defence the following papers were unpublished and had a status as follows: Paper 2: Accepted; Paper 3: Manuscript

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Svahn, Emelie. "Molecular machinery of a membrane-bound proton pump : Studies of charge transfer reactions in cytochrome c oxidase." Doctoral thesis, Stockholms universitet, Institutionen för biokemi och biofysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-108335.

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In cellular respiration, electron transfer from the breakdown of foodstuff is coupled to the formation of an electrochemical proton gradient. This is accomplished through proton translocation by respiratory complexes, and the proton gradient is subsequently used e.g. to drive ATP production. Consequently, proton- and electron-transfer reactions through the hydrophobic interior of membrane proteins are central to cellular respiration. In this thesis, proton- and electron transfer through an aa3-type terminal oxidase, cytochrome c oxidase (CytcO) from Rhodobacter sphaeroides, have been studied with the aim of understanding the molecular proton-transfer machinery of this proton pump. In the catalytic site of CytcO the electrons combine with protons and the terminal electron acceptor O2 to form water in an exergonic reaction that drives proton pumping. Therefore, CytcO must transfer both protons that are pumped and protons for the oxygen chemistry through its interior. This is done through its two proton-transfer pathways, termed the D pathway and the K pathway. Our studies have shown that the protons pumped during oxidation of CytcO are taken through the D pathway, and that this process does not require a functional K pathway. Furthermore, our data suggests that the K pathway is used for charge compensation of electron transfer to the catalytic site, but only in the A2 → P3 state transition. Our data also show that the water molecules identified in the crystal structures of CytcO play an important role in proton transfer through the D pathway. Finally, the effects of liposome reconstitution of CytcO on D-pathway proton transfer were investigated. The results suggest that the membrane modulates the rates of proton transfer through the D pathway, and also influences the extent of electron transfer between redox-active sites CuA and heme a.

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Dodia, R. J. "Structure-function relationship of mitochondrial cytochrome c oxidase : redox centres, proton pathways and isozymes." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1455977/.

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Cytochrome c oxidase (CcO) reduces O2 to water with four electrons from cytochromes c2+ and four matrix protons. The energy released is conserved in the protonmotive force by translocation of four additional protons into the intermembrane space. Electrons are transferred via CuA, haem a, to the binuclear centre; haem a3 and CuB, where O2 is reduced. Four major aspects of its structure/function have been investigated in this study. Mid-infrared (IR) spectroscopy has been used to probe redox-induced structural changes. By using electrochemically-poised samples of cyanide- and carbon monoxide-ligated bovine CcO these redox-linked IR changes were shown to be linked primarily with CuA and haem a metal centre transitions with fewer changes associated with transitions in haem a3 and CuB. CcO contains a cross-linked Tyr-His which is believed to form a Tyr radical in the PM intermediate. In this work, electrochemical conditions to induce Tyr-His model compound radicals have been combined with IR spectroscopy to record IR reference spectra. This has aided tentative assignment of IR bands at 1572 cm-1 or 1555 cm-1 to v8a(C-C), 1519 cm-1 to v7a(C-O.) to the phenoxyl radical and at 1336 cm-1 to a His ring stretch of the cross-linked structure in the PM state of bovine CcO. There is strong evidence from mutagenesis studies in bacterial CcOs that the well-conserved D channel is the proton translocation pathway. However, mutagenesis studies in a human/bovine hybrid CcO of an extensive hydrophilic H channel suggest that it fulfils this function, at least in mammalian CcOs. A structural model of Saccharomyces cerevisiae CcO produced by homology modelling indicates that it also contains an H channel (Maréchal, A., Meunier, B., Lee, D., Orengo, C. and Rich, P. R. (2012) Biochim. Biophys. Acta. 1817, 620-628). However, measurements of the H+/e- stoichiometry of a yeast H channel mutant (Q411L/Q413L/S458A/S455A) suggest it is not critical for proton translocation in yeast CcO. The nuclear-encoded subunit 5 of yeast CcO has two isoforms, 5A and 5B. COX5A is expressed aerobically and COX5B below 1 µM O2. They are reported to alter core catalytic activity; however comparisons were not strictly controlled. Here mutants were constructed where COX5B expression was controlled by the COX5A promoter yielding wild type levels of aerobically expressed 5B isozyme. Interestingly, this 5B isozyme exhibits the same catalytic activity and oxygen affinity as the 5A isozyme and the previously observed elevated activity must arise from a secondary effect.

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Punnagai, Munusami. "Electrostatic and quantum chemical investigation of the proton pumping mechanism of cytochrome c oxidase." kostenfrei, 2008. http://opus.ub.uni-bayreuth.de/volltexte/2008/475/.

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McCann, C. K. "The role of COX4 in the biogenesis of mitochondrial cytochrome c oxidase in Chlamydomonas reinhardtii." Thesis, University College London (University of London), 2009. http://discovery.ucl.ac.uk/18567/.

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The respiratory complexes of the mitochondrial electron transport chain are of dual genetic origin being encoded by both organellar and nuclear genes. Complicated regulatory mechanisms are needed to coordinate gene expression between the two genomes during biogenesis of the complexes. Investigation into the role of the nuclear genome in mitochondrial gene expression was carried out using the eukaryotic alga, Chlamydomonas reinhardtii, as a model organism. Previous analysis of nuclear mutants defective in respiratory function, isolated from an insertional mutagenesis population, identified one mutant, M86, with significantly reduced levels of the mitochondrial cox1 transcript encoding subunit 1 of cytochrome c oxidase (Lown, 2001). Molecular analysis in this thesis revealed that the insertion caused the deletion of COX4, encoding subunit 4 of cytochrome c oxidase. Subunit 4 is a peripheral subunit of cytochrome c oxidase located on the matrix side of the inner mitochondrial membrane – its functional role has not been established. Northern analysis of M86 indicates that, whilst the cox1 transcript is decreased to approximately 1 - 5 % of that in WT cells, other mitochondrial transcript levels are unaffected. These findings suggest that COX4 affects cox1 at the post-transcriptional level. Extremely low levels of the COX4 protein are shown to sustain cytochrome c oxidase activity, hence stoichiometric amounts of the subunit are not required for functioning of the enzyme. Preliminary studies to investigate further the function of the algal COX4 were performed by introducing missense point mutation into the protein, and techniques for screening for cytochrome c oxidase mutants were adapted and employed in C. reinhardtii. Analysis of the cox1 transcript in a yeast ΔCOX4 mutant showed that cox1 mRNA levels are unaffected. To our knowledge, C. reinhardtii illustrates the first example of a nuclear encoded subunit of an organellar complex also being a factor required for expression of an organelle-encoded subunit.

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Liao, Zhiming. "Molecular aspects of cardiac cytochrome C oxidase and extracellular matrix proteins in copper-deficient rats /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487853913100837.

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PENEDO, Diego Mattos. "An?lise gen?tica e fenot?pica de macacos-prego da Ilha da Marambaia, Mangaratiba, Rio de Janeiro." Universidade Federal Rural do Rio de Janeiro, 2016. https://tede.ufrrj.br/jspui/handle/jspui/1450.

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CAPES
Several studies have been conducted with capuchin monkeys (Sapajus and Cebus) in order to understand their evolutionary histories by South and Central America. Genetic analysis, in association with the coat coloration, assist in the identification of the relationships between species and show the diversity presented by both genera. In Brazil, Sapajus species are predominantly distributed, being S. nigritus endemic to the Atlantic Forest and characteristic of southeast. At Ilha da Marambaia, an important area with forest remaining in the state of Rio de Janeiro, there is a population of capuchin monkeys, but without previous study. The objective of this study was to characterize the population of capuchin monkeys at this region through phenotypic and genetic analyzes, including the coat coloration, the sequencing of the mitochondrial gene cytochrome oxidase II and the evaluation of karyotype with conventional staining and C-band. Interviews with residents and military personnel in the region, were also carried out, in order to identify the possible origin and isolation of the primates. Twelve specimens, eight males and four females, were analyzed. The coat features were consistent with that described for S. nigritus, with coloration varying from brown to blackish on the back, limbs, tail and top of the head, in addition to yellow chest and face with white or light yellow, contrasting. Tufts at the top of the head were seen in adults, being greater in females. The analysis of mitochondrial gene revealed closer proximity of this population with S. xanthosternos, which occurs at Bahia, and then with S. cay that occurs in parts of Brazil and Paraguay. The greatest divergence was in relation to the population of S. nigritus in Argentina. The karyotype was consistent with that described for Sapajus species, with 2n = 54 (XX or XY), although the morphology of the sex chromosome Y, submetacentric, was different from that commonly described in the literature (acrocentric). Presented intercalary C-band the chromosome pairs 4, 11, 12 and 17. The par 11 presented three polymorphisms, all interstitial to euchromatin and diversified from each other by deletion and inversion processes. The pattern of this pair is different from that described, as a small acrocentric, to S. nigritus in populations of Argentina, with banding similar to that considered specific for S. xanthosternos. According to the survey, the population of primates seems to be native of the island and is currently isolated. According to the genetic divergences found, the population of Ilha da Marambaia may have maintained ancestral characteristics. The C-band pattern of the pair 11 indicates that the polymorphism described for populations of Argentina does not correspond to the entire distribution of S. nigritus. These data may help to understand the diversity and evolution of Sapajus, since this would have radiated from southeastern Brazil. Further studies with populations from other regions of Rio de Janeiro are needed to verify the C-band pattern presented for the pair 11 as well as the genetic relationships demonstrated by the mitochondrial gene for the population of Ilha da Marambaia.
Diversos estudos v?m sendo realizados com macacos-prego e caiararas (Sapajus e Cebus) de modo a entender suas hist?rias evolutivas pelas Am?ricas do Sul e Central. An?lises gen?ticas, em associa??o ?s caracter?sticas de pelagem, auxiliam na identifica??o das rela??es entre as esp?cies e evidenciam a diversidade apresentada por ambos os g?neros. No Brasil, est?o distribu?das predominantemente as esp?cies de Sapajus, sendo S. nigritus end?mica de Mata Atl?ntica e caracter?stica do sudeste. Na Ilha da Marambaia, importante ?rea com remanescente florestal no estado do Rio de Janeiro, existe uma popula??o de macacos-prego, sem nenhum estudo anterior. O objetivo deste trabalho foi caracterizar a popula??o de macacos-prego dessa regi?o atrav?s de an?lises fenot?picas e gen?ticas, incluindo o padr?o de pelagem, o sequenciamento do gene mitocondrial Citocromo Oxidase II e a avalia??o do cari?tipo com colora??o convencional e bandamento de heterocromatina constitutiva (banda C). Foram realizadas, tamb?m, entrevistas com moradores e militares da regi?o, de modo a identificar a poss?vel origem e isolamento dos primatas. Foram analisados doze esp?cimes, oito machos e quatro f?meas. As caracter?sticas de pelagem coincidiram, de modo geral, com descrito para S. nigritus, sendo observada colora??o variando de marrom a enegrecida no dorso, membros, cauda e topo da cabe?a, al?m de peito amarelo e face branca ou amarelo-clara, contrastante. Tufos de pelos no topo da cabe?a foram observados nos adultos, sendo maiores nas f?meas. A an?lise do gene mitocondrial revelou maior proximidade da popula??o da ilha com S. xanthosternos, que ocorre na Bahia, e em seguida com S. cay, que ocorre em parte do Brasil e no Paraguai. A maior diverg?ncia apresentada foi em rela??o a popula??es de S. nigritus da Argentina. A an?lise do cari?tipo revelou padr?o condizente com as esp?cies de Sapajus, com 2n = 54 (XX ou XY), embora a morfologia do cromossomo sexual Y, submetac?ntrica, fosse divergente do comumente descrito na literatura (acroc?ntrica). Apresentaram banda C intercalar os pares cromoss?micos 4, 11, 12 e 17. O par 11 mostrou-se com tr?s polimorfismos, todos intercalares e diversificados entre si por processos de dele??o e invers?o. O padr?o deste par foi divergente do descrito, como um pequeno acroc?ntrico, para S. nigritus em popula??es da Argentina, apresentando bandamento semelhante ao considerado espec?fico de S. xanthosternos. Segundo o levantamento realizado, a popula??o de primatas parece ser natural da ilha, estando provavelmente isolada. De acordo com as diverg?ncias gen?ticas encontradas, a popula??o da Ilha da Marambaia pode ter conservado caracter?sticas ancestrais. O padr?o de banda C do par 11 indica que o polimorfismo descrito para popula??es da Argentina pode n?o corresponder a toda a distribui??o de S. nigritus. Estes dados podem auxiliar no entendimento da diversidade e evolu??o das esp?cies de Sapajus, uma vez que este teria irradiado a partir do sudeste brasileiro. Novos estudos com popula??es de outras regi?es do Rio de Janeiro s?o necess?rios para se averiguar o padr?o de bandamento de heterocromatina apresentada para o par 11, bem como as rela??es gen?ticas demonstradas pelo sequenciamento do gene mitocondrial para a popula??o da Ilha da Marambaia.

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41

Cvetkov, Teresa L. "Cytochrome c Oxidase from Rhodobacter sphaeroides: Oligomeric Structure in the Phospholipid Bilayer and the Structural and Functional Effects of a C-Terminal Truncation in Subunit III." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1279028849.

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42

Collins, Jessica M. "FixI and FixI2: Homologous proteins with unique functions in Sinorhizobium meliloti." Digital WPI, 2014. https://digitalcommons.wpi.edu/etd-theses/177.

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Cu+-ATPases are transmembrane enzymes that couple the efflux of cytoplasmic Cu+ to the hydrolysis of ATP. It is well established that Cu+-ATPases control cytoplasmic Cu+ levels. However, bacterial genomes, particularly those of symbiotic/pathogenic organisms, contain multiple copies of genes encoding Cu+-ATPases, challenging the idea of a singular role for these enzymes. Our lab has demonstrated that one of the two Cu+-ATPases in Pseudomonas aeruginosa, a FixI-type ATPase, has an alternative role, most likely Cu+ loading of cytochrome c oxidase (Cox). To further study alternative roles of Cu+-ATPases, we study the symbiont Sinorhizobium meliloti. Rhizobia are soil-dwelling bacteria that interact with legumes, forming plant root nodules that actively fix N2. The S. meliloti genome contains five Cu+-ATPases, two of which are FixI-type. Both of these enzymes, termed FixI1 and FixI2, are downstream of Cox operons. We hypothesized that the presence of multiple FixI-type ATPases was not an example of redundancy, but rather is an evolutionary adaptation that allows rhizobia to survive under the wide variety of adverse conditions faced during early infection and establishment of symbiosis. Towards this goal, this work focused on examining the effects of mutation of each ATPase on both free-living bacteria and on the ability of rhizobia to establish an effective symbiosis with its host legume. Each of these mutants presents a different phenotype at varying points of the nodulation process, and only the fixI2 mutation produces a respiratory-deficient phenotype during aerobic growth. These results are consistent with our hypothesis that the two proteins have non-redundant physiological functions. Understanding the factors that contribute to an effective symbiosis is beneficial, since N2 fixation in legumes is important to both agriculture and industry.

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43

Fisher, Kelli Nicole. "Investigating the Undefined Role of Subunit IIIin Cytochrome c Oxidase Functioning Using Dicyclohexylcarbodiimide Chemical Modification; Insight Into Enzyme Structure and Molecular Mechanism." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1405294648.

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44

Ioannidis, Nikolaos. "Intermediate states of mammalian cytochrome c oxidase : the resting/pulsed transition and the oxygen reduction reaction." Thesis, King's College London (University of London), 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424208.

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Janse, van Rensburg Marike. "The role of the cytochrome B and cytochrome C oxidase III genes in the immune response of the South African abalone, Haliotis midae." Master's thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/4275.

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Includes abstract.
Includes bibliographical references (leaves 80-89).
Although South Africa is the second largest producer of abalone outside Asia, the sustainability of the industry could be threatened by infectious diseases (Troell et ai., 2006). Probiotics are increasingly being viewed as an alternative to chemical and antibiotic treatments (Balcazar et al., 2006), and have been shown to improve the health of the South African abalone, Haliotis midae (Macey and Coyne, 2005). In order to establish better health management systems, and to implement alternative therapies such as probiotics, a better understanding of how the abalone immune system functions, and specifically how it responds to stimulation, is necessary. Two genes of the electron transport system, cytochrome b and cytochrome c oxidase III, were found to be upregulated in a cDNA microarray experiment performed on haemocytes from immunestimulated abalone (Arendze-Bailey, unpublished). The current study sought to confirm these results by semi-quantitative PCR and to further elucidate the roles of these genes, and thus the electron transport system, in the abalone immune response.

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White, Kimberly N. "Syntheses of analogs of the active site of cytochrome[c] oxidase and related new N-methylation metholodgy /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2006. http://uclibs.org/PID/11984.

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Faxén, Kristina. "Active transport of ions across biomembranes : a kinetic study of cytochrome c oxidase reconstituted into phospholipid vesicles /." Stockholm : Department of Biochemistry and Biophysics, stockholm university, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6806.

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Coulter, P. D. "Synthetic routes to doubly bridged porphyrins and their use as models for myoglobin and cytochrome c oxidase." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377220.

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Geyer, R. Ryan. "Investigating the Role of Subunit III in the Structure and Function of Rhodobacter Sphaeroides Cytochrome C Oxidase." Wright State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=wright1183979032.

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Omolewu, Rachel. "Characterization of Three Mutations in Conserved Domain of Subunit III of Cytochrome c Oxidase from Rhodobacter sphaeroides." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1292612174.

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Dissertations / Theses on the topic 'Cytochrome c Oxidase sunbunit I'

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