The enzyme, characterized from the bacterium Pseudomonas aeruginosa, differs from EC 1.14.15.20, heme oxygenase (biliverdin-producing, ferredoxin), in that the heme substrate is rotated by approximately 110 degrees within the active site, resulting in cleavage at a different part of the ring. It forms a mixture of about 70% biliverdin-IX-¦Ä and 30% biliverdin-IX-¦Â.
