Class of enzymes
In
enzymology , an unspecific monooxygenase (
EC
1.14.14.1 ) is an
enzyme that
catalyzes the
chemical reaction
RH + reduced flavoprotein + O2
⇌
{\displaystyle \rightleftharpoons }
ROH + oxidized flavoprotein + H2 O
The 3
substrates of this enzyme are RH (reduced substrate),
reduced flavoprotein , and
O2 , whereas its 3
products are ROH (oxidized substrate),
oxidized flavoprotein , and
H2 O .
This enzyme belongs to the family of
oxidoreductases , 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 reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen into the other donor. The
systematic name of this enzyme class is substrate,reduced-flavoprotein:oxygen oxidoreductase (RH-hydroxylating or -epoxidizing) . Other names in common use include microsomal monooxygenase , xenobiotic monooxygenase , aryl-4-monooxygenase , aryl hydrocarbon hydroxylase , microsomal P-450 , flavoprotein-linked monooxygenase , and flavoprotein monooxygenase . This enzyme participates in 7
metabolic pathways :
fatty acid metabolism ,
androgen and estrogen metabolism ,
gamma-hexachlorocyclohexane degradation ,
tryptophan metabolism ,
arachidonic acid metabolism ,
linoleic acid metabolism , and
metabolism of xenobiotics by cytochrome p450 . It employs one
cofactor ,
heme .
Structural studies
As of late 2007, 53
structures have been solved for this class of enzymes, with
PDB accession codes
1BU7 ,
1BVY ,
1DT6 ,
1FAG ,
1FAH ,
1JME ,
1JPZ ,
1N6B ,
1NR6 ,
1OG2 ,
1OG5 ,
1P0V ,
1P0W ,
1P0X ,
1PO5 ,
1PQ2 ,
1R9O ,
1SMI ,
1SMJ ,
1SUO ,
1TQN ,
1W0E ,
1W0F ,
1W0G ,
1YQO ,
1YQP ,
1Z10 ,
1Z11 ,
1ZO4 ,
1ZO9 ,
1ZOA ,
2BDM ,
2BMH ,
2F9Q ,
2FDU ,
2FDV ,
2FDW ,
2FDY ,
2HI4 ,
2HPD ,
2IJ2 ,
2IJ3 ,
2IJ4 ,
2J0D ,
2J1M ,
2J4S ,
2NNB ,
2P85 ,
2PG5 ,
2PG6 ,
2PG7 ,
2UWH , and
2V0M .
References
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Activity Regulation Classification Kinetics Types