Summary: Cytochrome C oxidase subunit II, transmembrane 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 220.127.116.11) 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:".
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- 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, transmembrane domain Provide feedback
The N-terminal domain of cytochrome C oxidase contains two transmembrane alpha-helices.
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
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR011759
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 enzyme complex consists of 3-4 subunits (prokaryotes) to up to 13 polypeptides (mammals).
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) (see INTERPRO), 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.
The N-terminal domain of cytochrome C oxidase contains two transmembrane alpha-helices [PUBMED:8638158].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||integral component of membrane (GO:0016021)|
|Biological process||electron transport chain (GO:0022900)|
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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:||2295|
|Average length of the domain:||85.50 aa|
|Average identity of full alignment:||24 %|
|Average coverage of the sequence by the domain:||26.29 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 26740544 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||14|
|Download:||download the raw HMM for this family|
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There are 10 interactions for this family. More...
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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_TM domain has been found. There are 88 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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