In the context of heme, metabolic biotransformation by heme oxygenase results in the selective opening of the alpha-methine bridge to form biliverdin/bilirubin. In this case, the resulting bilin carries the suffix IXα which indicates the parent molecule was protoporphyrin IX cleaved at the alpha position.
In the biochemical context of heme, the enzymatic process catalyzed by heme oxygenase involves the targeted opening of a bond in heme, resulting in biliverdin/bilirubin. The specific bilirubin derivative, bearing the suffix IXα, signifies that it was derived from protoporphyrin IX cleavage at the alpha position.