An oxygenase is any

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...

that oxidizes a substrate by transferring the

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ...

from molecular oxygen O₂ (as in air) to it. The oxygenases form a class of

oxidoreductase In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule, the reductant, also called the electron donor, to another, the oxidant, also called the electron acceptor. This group of enzymes usually u ...

s; their EC number is EC 1.13 or EC 1.14.

Discoverers

Oxygenases were discovered in 1955 simultaneously by two groups,

Osamu Hayaishi , was a Japanese biochemist, physiologist, and military physician. He discovered Oxygenases at the National Institute of Arthritis and Metabolic Diseases, National Institutes of Health in 1955. Citing his "outstanding and pioneering contributions ...

from Japan and Howard S. Mason from the US. Hayaishi was awarded the 1986

Wolf Prize in Medicine The Wolf Prize in Medicine is awarded annually by the Wolf Foundation in Israel. It is one of the six Wolf Prizes established by the Foundation and awarded since 1978; the others are in Agriculture, Chemistry, Mathematics, Physics and Arts. The ...

"for the discovery of the oxygenase enzymes and elucidation of their structure and biological importance."

Chemical Makeup

Oxygenases consist of both constitutive and inducible isozymes (HO-1, HO-2). These constitute a major intracellular source of

iron Iron () is a chemical element with Symbol (chemistry), symbol Fe (from la, Wikt:ferrum, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 element, group 8 of the periodic table. It is, Abundanc ...

and

carbon monoxide Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simple ...

Types

There are two types of oxygenases: *

Monooxygenase Monooxygenases are enzymes that incorporate one hydroxyl group (−OH) into substrates in many metabolic pathways. In this reaction, the two atoms of dioxygen are reduced to one hydroxyl group and one H2O molecule by the concomitant oxidation o ...

s, or

mixed function oxidase Mixed-function oxidase is the name of a family of oxidase enzymes that catalyze a reaction in which each of the two atoms of oxygen in O2 is used for a different function in the reaction. Oxidase is a general name for enzymes that catalyze oxidat ...

, transfer one oxygen atom to the substrate, and reduce the other oxygen atom to

water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...

. * Dioxygenases, or oxygen transferases, incorporate both atoms of molecular oxygen (O₂) into the product(s) of the reaction. Among the most important monooxygenases are the

cytochrome P450 oxidase Cytochromes P450 (CYPs) are a superfamily of enzymes containing heme as a cofactor that functions as monooxygenases. In mammals, these proteins oxidize steroids, fatty acids, and xenobiotics, and are important for the clearance of various compo ...

s, responsible for breaking down numerous chemicals in the body.

References

Enzymes Oxygenases {{enzyme-stub