Cytochrome C oxidase subunit II, transmembrane domain (IPR011759)

Short name: Cyt_c_oxidase_su2_TM_dom

Overlapping homologous superfamilies

Domain relationships



Cytochrome c oxidase (EC: [PMID: 6307356, PMID: 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 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 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 [PMID: 8638158].

GO terms

Biological Process

GO:0022900 electron transport chain

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0016021 integral component of membrane

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE profiles