Isoflavone reductase-like protein;

Isoflavone reductases (IFR) were identified in various legumes (pea, chickpea, soybean). Legumes(pea, chickpea, soybean) were identified and their cDNA cloned. These are mostly monomeric, NADPH-dependent reductases. Isoflavone reductases are involved in specific metabolic functions. Further isoflavone reductase-like proteins, "IFR-like proteins", with significant sequence homologies to the IFRs of legumes have been identified. Their functions are still unknown.

Isoflavones themselves are significantly involved in interactions between plants and the environment (bacteria, fungi, molluscs and herbivorous insects), especially in the legume family. They are components of non-specific resistance and defense mechanisms against harmful organisms. Furthermore, they enable the symbiosis of plants and rhizobial bacteria. They act as signal substances for nitrogen fixation by nodule bacteria. Isoflavones act as "chemoattractants" for these bacteria and induce nod gene expression for the nitrogen-containing root nodules of these plants.

1. Wang X et al (2006) Crystal structure of isoflavone reductase from alfalfa (Medicago sativa L.). J Mol Biol 358:1341-1352.
2. Dakora FD et al. (2996) Various functions of isoflavonoids in legumes transcend anti-microbial definitions of phytoalexins. Physiol Mol Plant Pathol 49:1-20.