Reaction: (1) liquiritigenin + O2 + [reduced NADPHhemoprotein reductase] = 2,4',7-trihydroxyisoflavanone + H2O + [oxidized NADPHhemoprotein reductase]
(2) (2S)-naringenin + O2 + [reduced NADPHhemoprotein reductase] = 2,4',5,7-tetrahydroxyisoflavanone + H2O + [oxidized NADPHhemoprotein reductase]
For diagram of reaction click here.
Glossary: liquiritigenin = 4',7-dihydroxyflavanone
(2S)-naringenin = 4',5,7-dihydroxyflavanone
2,4',5,7-tetrahydroxyisoflavanone = 2-hydroxy-2,3-dihydrogenistein
Other name(s): CYP93C; IFS; isoflavonoid synthase
Systematic name: liquiritigenin, [reduced NADPHhemoprotein reductase]:oxygen oxidoreductase (hydroxylating, aryl migration)
Comments: A cytochrome P-450 (heme thiolate) protein found in plants. The reaction involves the migration of the 2-phenyl group of the flavanone to the 3-position of the isoflavanone. The 2-hydroxyl group is derived from the oxygen molecule. EC 184.108.40.206, 2-hydroxyisoflavanone dehydratase, acts on the products with loss of water and formation of genistein and daidzein, respectively.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
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