In
enzymology, a 3-hydroxybenzoate 4-monooxygenase () is an
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...
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
A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and break ...
:3-hydroxybenzoate + NADPH + H
+ + O
2 3,4-dihydroxybenzoate + NADP
+ + H
2O
The 4
substrates of this enzyme are
3-hydroxybenzoate,
NADPH,
H+, and
O2, whereas its 3
products are
3,4-dihydroxybenzoate
Protocatechuic acid (PCA) is a dihydroxybenzoic acid, a type of phenolic acid. It is a major metabolite of antioxidant polyphenols found in green tea. It has mixed effects on normal and cancer cells in ''in vitro'' and ''in vivo'' studies.
Biolo ...
,
NADP+, and
H2O.
This enzyme belongs to the family 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 ...
s, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with NADH or NADPH as one donor, and incorporation of one atom o oxygen into the other donor. The
systematic name of this enzyme class is 3-hydroxybenzoate,NADPH:oxygen oxidoreductase (4-hydroxylating). This enzyme is also called 3-hydroxybenzoate 4-hydroxylase. This enzyme participates in
benzoate degradation via hydroxylation and
2,4-dichlorobenzoate degradation. It employs one
cofactor,
FAD.
Structural studies
As of late 2007, two
structures have been solved for this class of enzymes, with
PDB accession codes and .
References
*
*
EC 1.14.13
NADPH-dependent enzymes
Flavoproteins
Enzymes of known structure
{{1.14.13-enzyme-stub