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 188.8.131.52, isoflavone 2′-hydroxylase, is less specific and acts on other isoflavones as well as 4′-methoxyisoflavones.
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.