4'-methoxyisoflavone 2'-hydroxylase;
isoflavone 2'-monooxygenase (ambiguous);
isoflavone 2'-hydroxylase (ambiguous)

Oxidoreductases;
Acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2;
With NADH or NADPH as one donor, and incorporation of one atom of oxygen into the other donor

formononetin,NADPH:oxygen oxidoreductase (2'-hydroxylating)

formononetin + NADPH + H+ + O2 = 2'-hydroxyformononetin + NADP+ + H2O [RN:R06560]

R06560

formononetin [CPD:C00858];
NADPH [CPD:C00005];
H+ [CPD:C00080];
O2 [CPD:C00007]

A heme-thiolate protein (P-450). Acts on isoflavones with a 4'-methoxy group, such as formononetin and biochanin A. Involved in the biosynthesis of the pterocarpin phytoalexins medicarpin and maackiain. EC 1.14.13.89, isoflavone 2'-hydroxylase, is less specific and acts on other isoflavones as well as 4'-methoxyisoflavones.

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.