Biopterin

Biopterin is a coenzyme that is produced within the body.

It is an oxidized degradation product of tetrahydrobiopterin.

Defects in biopterin synthesis or regeneration can cause a form of hyperphenylalaninemia (a disease with symptoms similar to PKU).

Biopterin is synthesized in several parts of the body, including the pineal gland.

Biopterin deficiency has been associated with a variety of disorders, including dystonia and rabies.