Oxygenase
Encyclopedia
An oxygenase is any enzyme
that oxidizes
a substrate
by transferring the oxygen
from molecular oxygen O2 (as in air) to it. The oxygenases form a class of oxidoreductase
s; their EC number
is EC 1.13 or EC 1.14.
Oxygenases were discovered in 1955 simultaneously by two groups, Osamu Hayaishi
from Japan and Howard S. Mason from the US.
There are two types of oxygenases:
Among the most important monooxygenases are the cytochrome P450 oxidase
s, responsible for breaking down numerous chemicals in the body.
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that oxidizes
Redox
Redox reactions describe all chemical reactions in which atoms have their oxidation state changed....
a substrate
Substrate (biochemistry)
In biochemistry, a substrate is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the substrate. In the case of a single substrate, the substrate binds with the enzyme active site, and an enzyme-substrate complex is formed. The substrate is transformed into one or...
by transferring the oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
from molecular oxygen O2 (as in air) to it. The oxygenases form a class of oxidoreductase
Oxidoreductase
In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule to another...
s; their EC number
EC number
The Enzyme Commission number is a numerical classification scheme for enzymes, based on the chemical reactions they catalyze....
is EC 1.13 or EC 1.14.
Oxygenases were discovered in 1955 simultaneously by two groups, Osamu Hayaishi
Osamu Hayaishi
is a Japanese biologist and a professor at Osaka Bioscience Institute.- Birth and education :Osamu Hayaishi was born in Stockton, California, U.S.A, in 1920. He completed his M.D. from Osaka University in 1942.- Academic career :...
from Japan and Howard S. Mason from the US.
There are two types of oxygenases:
- Monooxygenases, or mixed function oxidaseMixed function oxidaseMixed-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....
, transfer one oxygen atom to the substrate, and reduce the other oxygen atom to waterWaterWater is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
. - DioxygenasesDioxygenaseIn molecular biology, a dioxygenase is an enzyme which catalyses the incorporation of both atoms of molecular oxygen into substrates using a variety of reaction mechanisms. Cleavage of aromatic rings is one of the most important functions of dioxygenases, which play key roles in the degradation of...
, 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
Cytochrome P450 oxidase
The cytochrome P450 superfamily is a large and diverse group of enzymes. The function of most CYP enzymes is to catalyze the oxidation of organic substances. The substrates of CYP enzymes include metabolic intermediates such as lipids and steroidal hormones, as well as xenobiotic substances...
s, responsible for breaking down numerous chemicals in the body.