Cytochrome c oxidase
Cytochrome c oxidase (pronunciation: /ˈsaɪtoʊkroʊm siː ɒkˈsɪdeɪz/), also known as Complex IV, is an enzyme that is part of the mitochondrial electron transport chain. It is the last enzyme in the respiratory chain, playing a crucial role in cellular respiration and energy production.
Etymology
The term "cytochrome" comes from the Greek words "kytos" meaning "cell" and "chroma" meaning "color". This is due to the characteristic color changes these proteins undergo upon oxidation or reduction. The "c" in cytochrome c oxidase refers to the specific type of cytochrome, which is a heme-containing protein. "Oxidase" refers to the enzyme's ability to oxidize substrates, in this case, reducing molecular oxygen to water.
Function
Cytochrome c oxidase is responsible for the transfer of electrons from cytochrome c to oxygen, which results in the reduction of oxygen to water. This process is coupled with the pumping of protons across the inner mitochondrial membrane, contributing to the proton gradient that drives ATP synthesis.
Structure
The enzyme is a large protein complex that consists of multiple subunits. In humans, it is composed of 13 polypeptide subunits, three of which are encoded by mitochondrial DNA, while the rest are nuclear-encoded.
Clinical significance
Deficiencies in cytochrome c oxidase can lead to a number of mitochondrial diseases, such as Leigh syndrome and Alzheimer's disease. These conditions are often characterized by impaired energy production and increased oxidative stress.
Related terms
This WikiMD.org article is a stub. You can help make it a full article.