protoporphyrin

(prōt″ō-por′fĭ-rĭn )

To hear audio pronunciation of this topic, purchase a subscription or log in.

[ proto- + porphyrin ]
A derivative of hemoglobin containing four pyrrole nuclei; C₃₄H₃₄N₄O₄. It occurs naturally and is formed from heme (ferriprotoporphyrin) by deletion of an atom of iron.

There's more to see -- the rest of this topic is available only to subscribers.