Summary: Cytochrome C oxidase subunit II, periplasmic domain
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Cytochrome c oxidase subunit II Edit Wikipedia article
|, mitochondrially encoded cytochrome c oxidase II, COII, MTCO2, Cytochrome c oxidase subunit II, CO II|
|Cytochrome c oxidase subunit II, transmembrane domain|
Bacterial cytochrome c oxidase complex. Subunit II indicated by blue.
|Cytochrome C oxidase subunit II, periplasmic domain|
Cytochrome c oxidase subunit II, abbreviated COXII, COX2, COII, or MT-CO2, is the second subunit of cytochrome c oxidase.
Cytochrome c oxidase (EC 126.96.36.199) is an oligomeric enzymatic complex which is a component of the respiratory chain and is involved in the transfer of electrons from cytochrome c to oxygen. In eukaryotes this enzyme complex is located in the mitochondrial inner membrane; in aerobic prokaryotes it is found in the plasma membrane. The enzyme complex consists of 3-4 subunits (prokaryotes) to up to 13 polypeptides (mammals). In Leigh's disease, there may be an abnormality or deficiency of cytochrome oxidase.
Subunit 2 (COII) transfers the electrons from cytochrome c to the catalytic subunit 1. It contains two adjacent transmembrane regions in its N-terminus and the major part of the protein is exposed to the periplasmic or to the mitochondrial intermembrane space, respectively. COII provides the substrate-binding site and contains a copper centre called Cu(A) (see InterPro: IPR001505), probably the primary acceptor in cytochrome c oxidase. An exception is the corresponding subunit of the cbb3-type oxidase which lacks the copper A redox-centre. Several bacterial COII have a C-terminal extension that contains a covalently bound haem c.
The N-terminal domain of cytochrome C oxidase contains two transmembrane alpha-helices.
- GRCh38: Ensembl release 89: ENSG00000198712 - Ensembl, May 2017
- GRCm38: Ensembl release 89: ENSMUSG00000064354 - Ensembl, May 2017
- "Human PubMed Reference:".
- "Mouse PubMed Reference:".
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- Anderson S, Bankier AT, Barrell BG, de Bruijn MH, Coulson AR, Drouin J, Eperon IC, Nierlich DP, Roe BA, Sanger F, Schreier PH, Smith AJ, Staden R, Young IG (Apr 1981). "Sequence and organization of the human mitochondrial genome". Nature. 290 (5806): 457–65. PMID 7219534. doi:10.1038/290457a0.
- Montoya J, Ojala D, Attardi G (Apr 1981). "Distinctive features of the 5'-terminal sequences of the human mitochondrial mRNAs". Nature. 290 (5806): 465–70. PMID 7219535. doi:10.1038/290465a0.
- Horai S, Hayasaka K, Kondo R, Tsugane K, Takahata N (Jan 1995). "Recent African origin of modern humans revealed by complete sequences of hominoid mitochondrial DNAs". Proceedings of the National Academy of Sciences of the United States of America. 92 (2): 532–6. PMC . PMID 7530363. doi:10.1073/pnas.92.2.532.
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Cytochrome C oxidase subunit II, periplasmic domain Provide feedback
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Tsukihara T, Aoyama H, Yamashita E, Tomizaki T, Yamaguchi H, Shinzawa-Itoh K, Nakashima R, Yaono R, Yoshikawa S; , Science 1996;272:1136-1144.: The whole structure of the 13-subunit oxidized cytochrome c oxidase at 2.8 A. PUBMED:8638158 EPMC:8638158
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This tab holds annotation information from the InterPro database.
InterPro entry IPR002429
Cytochrome c oxidase (EC) [PUBMED:6307356, PUBMED:8083153] is an oligomeric enzymatic complex which is a component of the respiratory chain and is involved in the transfer of electrons from cytochrome c to oxygen. In eukaryotes this enzyme complex is located in the mitochondrial inner membrane; in aerobic prokaryotes it is found in the plasma membrane. The number of polypeptides in the complex ranges from 3-4 (prokaryotes), up to 13(mammals). In Archaea, a cytochrome-c-type oxidase from Natronobacterium (cytochrome ba3) has been shown to consists of four subunits [PUBMED:9428682].
Subunit 2 (CO II) transfers the electrons from cytochrome c to the catalytic subunit 1. It contains two adjacent transmembrane regions in its N terminus and the major part of the protein is exposed to the periplasmic or to the mitochondrial intermembrane space, respectively. CO II provides the substrate-binding site and contains a copper centre called Cu(A), probably the primary acceptor in cytochrome c oxidase. An exception is the corresponding subunit of the cbb3-type oxidase which lacks the copper A redox-centre. Several bacterial CO II have a C-terminal extension that contains a covalently bound haem c.
It has been shown [PUBMED:1324168, PUBMED:1324835] that nitrous oxide reductase (gene nosZ) of Pseudomonas has sequence similarity in its C terminus to CO II. This enzyme is part of the bacterial respiratory system which is activated under anaerobic conditions in the presence of nitrate or nitrous oxide. NosZ is a periplasmic homodimer that contains a dinuclear copper centre, probably located in a 3-dimensional fold similar to the cupredoxin-like fold that has been suggested for the copper-binding site of CO II [PUBMED:1324168].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||membrane (GO:0016020)|
|Molecular function||copper ion binding (GO:0005507)|
|cytochrome-c oxidase activity (GO:0004129)|
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
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Many of the proteins in this family contain multiple similar copies of this plastocyanin-like domain.
The clan contains the following 15 members:Copper-bind COX2 COX_ARM Cu-oxidase Cu-oxidase_2 Cu-oxidase_3 Cu_bind_like Cupredoxin_1 CzcE DP-EP Ephrin hGDE_N PAD_N PixA SoxE
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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|Author:||Sonnhammer ELL , Griffiths-Jones SR|
|Number in seed:||11|
|Number in full:||8256|
|Average length of the domain:||101.80 aa|
|Average identity of full alignment:||30 %|
|Average coverage of the sequence by the domain:||32.26 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 45638612 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||20|
|Download:||download the raw HMM for this family|
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Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
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The tree shows the occurrence of this domain across different species. More...
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There are 16 interactions for this family. More...
We determine these interactions using iPfam, which considers the interactions between residues in three-dimensional protein structures and maps those interactions back to Pfam families. You can find more information about the iPfam algorithm in the journal article that accompanies the website.
For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the COX2 domain has been found. There are 187 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.
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