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 flavonoid 3'-monooxygenase (, was wrongly classified as in the past) 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
:a flavonoid + NADPH + H
+ + O
2 a 3'-hydroxyflavonoid + NADP
+ + H
2O
The 4
substrates of this enzyme are
flavonoid
Flavonoids (or bioflavonoids; from the Latin word ''flavus'', meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans.
Chemically, flavonoids ...
,
NADPH
Nicotinamide adenine dinucleotide phosphate, abbreviated NADP or, in older notation, TPN (triphosphopyridine nucleotide), is a cofactor used in anabolic reactions, such as the Calvin cycle and lipid and nucleic acid syntheses, which require NAD ...
,
H+, and
O2, whereas its 3
products are
3'-hydroxyflavonoid,
NADP+, and
H2O.
This enzyme belongs to the family of
oxidoreductases, specifically those acting on paired donors, with O
2 as
oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O
2 with NADH or NADPH as one donor, and incorporation of one atom of oxygen into the other donor. The
systematic name of this enzyme class is flavonoid,NADPH:oxygen oxidoreductase (3'-hydroxylating). Other names in common use include flavonoid 3'-hydroxylase, flavonoid 3-hydroxylase (erroneous), NADPH:flavonoid-3'-hydroxylase, and flavonoid 3-monooxygenase (erroneous). This enzyme participates in
flavonoid biosynthesis.
References
EC 1.14.14
NADPH-dependent enzymes
Enzymes of unknown structure
Flavonoids metabolism
{{1.14-enzyme-stub