IUBMB Enzyme Nomenclature


Accepted name: (3R)-2'-hydroxyisoflavanone reductase

Reaction: a (4R)-4,2'-dihydroxyisoflavan + NADP+ = a (3R)-2'-hydroxyisoflavanone + NADPH + H+

For diagram of reaction click here

Glossary: (3R)-vestitone = (3R)-2',7-dihydroxy-4'-methoxyisoflavanone

Other name(s): vestitone reductase; pterocarpin synthase (incorrect); pterocarpan synthase (incorrect)

Systematic name: (3R)-2'-hydroxyisoflavanone:NADP+ 4-oxidoreductase

Comments: This plant enzyme participates in the biosynthesis of the pterocarpan phytoalexins medicarpin, maackiain, and several forms of glyceollin. The ezyme has a strict stereo specificity for the 3R-isoflavanones.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 118477-70-6


1. Bless, W. and Barz, W. Isolation of pterocarpan synthase, the terminal enzyme of pterocarpan phytoalexin biosynthesis in cell-suspension cultures of Cicer arietinum. FEBS Lett. 235 (1988) 47-50.

2. Guo, L., Dixon, R.A. and Paiva, N.L. Conversion of vestitone to medicarpin in alfalfa (Medicago sativa L.) is catalyzed by two independent enzymes. Identification, purification, and characterization of vestitone reductase and 7,2'-dihydroxy-4'-methoxyisoflavanol dehydratase. J. Biol. Chem. 269 (1994) 22372-22378. [PMID: 8071365]

3. Guo, L., Dixon, R.A. and Paiva, N.L. The ‘pterocarpan synthase’ of alfalfa: association and co-induction of vestitone reductase and 7,2'-dihydroxy-4'-methoxy-isoflavanol (DMI) dehydratase, the two final enzymes in medicarpin biosynthesis. FEBS Lett. 356 (1994) 221-225. [PMID: 7805842]

4. Guo, L. and Paiva, N.L. Molecular cloning and expression of alfalfa (Medicago sativa L.) vestitone reductase, the penultimate enzyme in medicarpin biosynthesis. Arch. Biochem. Biophys. 320 (1995) 353-360. [PMID: 7625843]

5. Shao, H., Dixon, R.A. and Wang, X. Crystal structure of vestitone reductase from alfalfa (Medicago sativa L.). J. Mol. Biol. 369 (2007) 265-276. [PMID: 17433362]

[EC created 1992 as EC, part transferred 2013 to EC]

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