Main Reaction: L-tryptophan + (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + O2 >> 5-hydroxy-L-tryptophan + 4a-hydroxy-tetrahydrobiopterin

Reference: PubMed ID: 12379098
Authors: Wang L, Erlandsen H, Haavik J, Knappskog PM, Stevens RC
Title: Three-dimensional structure of human tryptophan hydroxylase and its implications for the biosynthesis of the neurotransmitters serotonin and melatonin.
Published: 2002 Oct 22

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