Tags: Protein.
Tryptophan hydroxylase 1 (tryptophan 5-monooxygenase) also known as TPH1 is an enzyme which in humans is encoded by the TPH1 gene.TPH1 was first discovered to synthesize serotonin in 1988 and was thought that there only was a single TPH gene until 2003 while a second form was found in the mouse (Tph2) rat and human brain (TPH2) and the original Tph/TPH was then renamed to Tph1/TPH1.