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The complex is a large [[lipoprotein]] composed of several [[metal]] prosthetic sites and 13 protein subunits. In mammals, ten subunits are nuclear in origin and three are synthesized mitochondrially. The complex contains two [[cytochrome]]s, the ''a'' and ''a''<sub>3</sub> cytochromes, and two [[copper]] centers, the Cu<sub>A</sub> and Cu<sub>B</sub> centers. In fact, the cytochrome ''a''<sub>3</sub> and Cu<sub>B</sub> are a binuclear center that is the site of oxygen reduction. The mechanism of action of this large complex is still an active research topic.
The complex is a large [[lipoprotein]] composed of several [[metal]] prosthetic sites and 13 protein subunits. In mammals, ten subunits are nuclear in origin and three are synthesized mitochondrially. The complex contains two [[cytochrome]]s, the ''a'' and ''a''<sub>3</sub> cytochromes, and two [[copper]] centers, the Cu<sub>A</sub> and Cu<sub>B</sub> centers. In fact, the cytochrome ''a''<sub>3</sub> and Cu<sub>B</sub> are a binuclear center that is the site of oxygen reduction. The mechanism of action of this large complex is still an active research topic.


[[Cyanide]], [[carbon monoxide]], [[hydrogen sulfide|sulfide]] and [[azide]] all bind to Cytochrome c Oxidase, thus inhibiting the protein from functioning which results in chemical [[suffocation]].
[[Cyanide]],[[hydrogen sulfide|sulfide]] and [[azide]] all bind to Cytochrome c Oxidase, thus inhibiting the protein from functioning which results in chemical [[suffocation]].


==External links==
==External links==

Revision as of 20:55, 7 December 2006

File:CytochromeCOxidase-2OCC.png
Cytochrome c oxidase

The enzyme cytochrome c oxidase (PDB: 2OCC​, EC 1.9.3.1) is a large transmembrane protein complex found in bacteria and the mitochondrion. It is the terminal electron acceptor in the electron transport chain in mitochondria and bacteria from four molecules of cytochrome c and converting molecular oxygen to two molecules of water. In the process, it translocates four protons, helping to establish a chemiosmotic potential that the ATP synthase then uses to synthesize ATP.

Summary reaction:

4 Fe2+-cytochrome c + 8 H+in + O2 → 4 Fe3+-cytochrome c + 2 H2O + 4 H+out

The complex is a large lipoprotein composed of several metal prosthetic sites and 13 protein subunits. In mammals, ten subunits are nuclear in origin and three are synthesized mitochondrially. The complex contains two cytochromes, the a and a3 cytochromes, and two copper centers, the CuA and CuB centers. In fact, the cytochrome a3 and CuB are a binuclear center that is the site of oxygen reduction. The mechanism of action of this large complex is still an active research topic.

Cyanide,sulfide and azide all bind to Cytochrome c Oxidase, thus inhibiting the protein from functioning which results in chemical suffocation.