In
enzymology
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. A ...
, a glutathione oxidase () is an
enzyme that
catalyzes
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...
the
chemical reaction
:2 glutathione + O
2 glutathione disulfide + H
2O
2
Thus, the two
substrates of this enzyme are
glutathione and
O2, whereas its two
products are
glutathione disulfide
Glutathione disulfide (GSSG) is a disulfide derived from two glutathione molecules.
In living cells, glutathione disulfide is reduced into two molecules of glutathione with reducing equivalents from the coenzyme NADPH. This reaction is catalyzed ...
and
H2O2.
This enzyme belongs to the family of
oxidoreductases, specifically those acting on a sulfur group of donors with oxygen as acceptor. The
systematic name of this enzyme class is glutathione:oxygen oxidoreductase. This enzyme participates in
glutathione metabolism
Glutathione (GSH, ) is an antioxidant in plants, animals, fungi, and some bacteria and archaea. Glutathione is capable of preventing damage to important cellular components caused by sources such as reactive oxygen species, free radicals, pe ...
. It employs one
cofactor,
FAD.
References
*
EC 1.8.3
Flavoproteins
Enzymes of unknown structure
{{1.8-enzyme-stub