Q9ZZ52 · COX1_SQUAC

Function

function

Component of the cytochrome c oxidase, the last enzyme in the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes succinate dehydrogenase (complex II, CII), ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to transfer electrons derived from NADH and succinate to molecular oxygen, creating an electrochemical gradient over the inner membrane that drives transmembrane transport and the ATP synthase. Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Electrons originating from reduced cytochrome c in the intermembrane space (IMS) are transferred via the dinuclear copper A center (CU(A)) of subunit 2 and heme A of subunit 1 to the active site in subunit 1, a binuclear center (BNC) formed by heme A3 and copper B (CU(B)). The BNC reduces molecular oxygen to 2 water molecules using 4 electrons from cytochrome c in the IMS and 4 protons from the mitochondrial matrix.

Catalytic activity

Cofactor

Protein has several cofactor binding sites:
heme (UniProtKB | Rhea| CHEBI:30413 )

Note: Binds 2 heme A groups non-covalently per subunit.
Cu cation (UniProtKB | Rhea| CHEBI:23378 )

Note: Binds a copper B center.

Pathway

Energy metabolism; oxidative phosphorylation.

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site40Na+ (UniProtKB | ChEBI)
Binding site45Na+ (UniProtKB | ChEBI)
Binding site61Fe (UniProtKB | ChEBI) of Fe(II)-heme a (UniProtKB | ChEBI); low-spin; axial binding residue
Binding site240Cu cation B (UniProtKB | ChEBI)
Binding site244O2 (UniProtKB | ChEBI)
Binding site290Cu cation B (UniProtKB | ChEBI)
Binding site291Cu cation B (UniProtKB | ChEBI)
Binding site368Mg2+ (UniProtKB | ChEBI); ligand shared with MT-CO2
Binding site369Mg2+ (UniProtKB | ChEBI); ligand shared with MT-CO2
Binding site376Fe (UniProtKB | ChEBI) of heme a3 (UniProtKB | ChEBI); high-spin; axial binding residue
Binding site378Fe (UniProtKB | ChEBI) of Fe(II)-heme a (UniProtKB | ChEBI); low-spin; axial binding residue
Binding site441Na+ (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentmitochondrial respiratory chain complex IV
Cellular Componentrespiratory chain complex IV
Molecular Functioncytochrome-c oxidase activity
Molecular Functionheme binding
Molecular Functionmetal ion binding
Biological Processelectron transport coupled proton transport
Biological Processmitochondrial electron transport, cytochrome c to oxygen

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Cytochrome c oxidase subunit 1
  • EC number
  • Alternative names
    • Cytochrome c oxidase polypeptide I

Gene names

    • Name
      MT-CO1
    • Synonyms
      COI, COXI, MTCO1

Encoded on

  • Mitochondrion

Organism names

  • Taxonomic identifier
  • Taxonomic lineage
    Eukaryota > Metazoa > Chordata > Craniata > Vertebrata > Chondrichthyes > Elasmobranchii > Squalomorphii > Squaliformes > Squalidae > Squalus

Accessions

  • Primary accession
    Q9ZZ52

Subcellular Location

Features

Showing features for topological domain, transmembrane.

TypeIDPosition(s)Description
Topological domain1-11Mitochondrial matrix
Transmembrane12-40Helical; Name=I
Topological domain41-50Mitochondrial intermembrane
Transmembrane51-86Helical; Name=II
Topological domain87-94Mitochondrial matrix
Transmembrane95-117Helical; Name=III
Topological domain118-140Mitochondrial intermembrane
Transmembrane141-170Helical; Name=IV
Topological domain171-182Mitochondrial matrix
Transmembrane183-212Helical; Name=V
Topological domain213-227Mitochondrial intermembrane
Transmembrane228-261Helical; Name=VI
Topological domain262-269Mitochondrial matrix
Transmembrane270-286Helical; Name=VII
Topological domain287-298Mitochondrial intermembrane
Transmembrane299-327Helical; Name=VIII
Topological domain328-335Mitochondrial matrix
Transmembrane336-357Helical; Name=IX
Topological domain358-370Mitochondrial intermembrane
Transmembrane371-400Helical; Name=X
Topological domain401-406Mitochondrial matrix
Transmembrane407-433Helical; Name=XI
Topological domain434-446Mitochondrial intermembrane
Transmembrane447-478Helical; Name=XII
Topological domain479-518Mitochondrial matrix

Keywords

PTM/Processing

Features

Showing features for chain, cross-link.

TypeIDPosition(s)Description
ChainPRO_00001834211-518Cytochrome c oxidase subunit 1
Cross-link240↔2441'-histidyl-3'-tyrosine (His-Tyr)

Interaction

Subunit

Component of the cytochrome c oxidase (complex IV, CIV), a multisubunit enzyme composed of 14 subunits. The complex is composed of a catalytic core of 3 subunits MT-CO1, MT-CO2 and MT-CO3, encoded in the mitochondrial DNA, and 11 supernumerary subunits COX4I, COX5A, COX5B, COX6A, COX6B, COX6C, COX7A, COX7B, COX7C, COX8 and NDUFA4, which are encoded in the nuclear genome. The complex exists as a monomer or a dimer and forms supercomplexes (SCs) in the inner mitochondrial membrane with NADH-ubiquinone oxidoreductase (complex I, CI) and ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII), resulting in different assemblies (supercomplex SCI1III2IV1 and megacomplex MCI2III2IV2) (By similarity).
As a newly synthesized protein, rapidly incorporates into a multi-subunit assembly intermediate in the inner membrane, called MITRAC (mitochondrial translation regulation assembly intermediate of cytochrome c oxidase) complex, whose core components are COA3/MITRAC12 and COX14. Within the MITRAC complex, interacts with COA3 and with SMIM20/MITRAC7; the interaction with SMIM20 stabilizes the newly synthesized MT-CO1 and prevents its premature turnover. Interacts with TMEM177 in a COX20-dependent manner (By similarity).

Structure

Family & Domains

Sequence similarities

Keywords

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    518
  • Mass (Da)
    57,267
  • Last updated
    1999-05-01 v1
  • Checksum
    4D90C32D7739ECF5
MAINRWFFSTNHKDIGTLYLIFGAWAGMVGTALSLLIRAELSQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPVMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSLLLLLASAGVEAGAGTGWTVYPPLAGNMAHAGASVDLAIFSLHLAGISSILASINFITTIINMKPPAISQYQTPLFVWSILVTTILLLLSLPVLAAAITMLLTDRNLNTTFFDPAGGGDPILYQHLFWFFGHPEVYILILPGFGMISHVVAYYSGKKEPFGYMGMVWAMMAIGLLGFIVWAHHMFTVGMDVDTRAYFTSATMIIAIPTGVKVFSWLATLHGGSIKWETPLLWALGFIFLFTVGGLTGIVLANSSLDIVLHDTYYVVAHFHYVLSMGAVFAIMAGFIHWFPLFSGYTLHSTWTKTQFLVMFIGVNLTFFPQHFLGLAGMPRRYSDYPDAYALWNTVSSIGSLISLVAVIMFLFIIWEAFAPSGKVLSVELPHTNVEWLHGCPPPYHTYEEPAFVQVQRTYF

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
Y18134
EMBL· GenBank· DDBJ
CAA77051.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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