IUBMB Enzyme Nomenclature


Accepted name: isoflavone 3'-hydroxylase

Reaction: formononetin + NADPH + H+ + O2 = calycosin + NADP+ + H2O

For diagram click here.

Other name(s): isoflavone 3'-monooxygenase

Systematic name: formononetin,NADPH:oxygen oxidoreductase (3'-hydroxylating)

Comments: A heme-thiolate protein (P-450). Also acts on biochanin A and other isoflavones with a 4'-methoxy group. Involved in the biosynthesis of the pterocarpin phytoalexins medicarpin and maackiain.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 110183-50-1


1. Hinderer, W., Flentje, U. and Barz, W. Microsomal isoflavone 2'-hydroxylases and 3'-hydroxylases from chickpea (Cicer arietinum L) cell-suspensions induced for pterocarpan phytoalexin formation. FEBS Lett. 214 (1987) 101-106.

[EC created 1992]

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