ID 4.2.1.139 DE pterocarpan synthase. AN 2',7-dihydroxy-4'-methoxyisoflavanol dehydratase. AN 2'-hydroxyisoflavanol 4,2'-dehydratase. AN 7,2'-dihydroxy-4'-methoxyisoflavanol dehydratase. AN medicarpan synthase. AN medicarpin synthase. CA a (4R)-4,2'-dihydroxyisoflavan = a pterocarpan + H2O. CC -!- The enzyme catalyzes the formation of the additional ring in CC pterocarpan, the basic structure of phytoalexins produced by CC leguminous plants, including (-)-medicarpin, (+)-medicarpin, (-)- CC maackiain and (+)-maackiain. CC -!- The enzyme requires that the hydroxyl group at C-4 of the substrate CC is in the (4R) configuration. CC -!- The configuration of the hydrogen atom at C-3 determines whether the CC pterocarpan is the (+)- or (-)-enantiomer. CC -!- The enzyme contains amino acid motifs characteristic of dirigent CC proteins. CC -!- Formerly EC 1.1.1.246. DR A0A1V1FH01, DIR_GLYEC ; I1JNN8, DIR_SOYBN ; //