Structural Biological Study of Biliverdin Reductase.

In mammals, heme is degraded to biliverdin by heme oxygenase (HO) and subsequently, the biliverdin is reduced to bilirubin by biliverdin reductase (BVR) . The metabolic waste product, bilirubin is now becoming recognized as having functional importance. It appears to play a key role in oxidative stress defense in vivo. Thus, heme degradation pathway has seen renewed interest in its biosynthesis. Recently, the X-ray crystal structures of HO and BVR were determined. Based on the structures, new insights into the mechanism of the heme degradation and bilirubin synthesis are discussed.