Biology 382 - Proteins of Interest

Enzymes in biopterin (Tetrahydrobiopterin, BH4) synthesis / regeneration pathways:
BH4 synthesis figure, Further information on BH4

  • GTP Cyclohydrolase I (aka GCH, GCH1, GTPCH)

  • GTP Cyclohydrolase feedback regulatory protein (aka GFRP)

  • Pyruvoyl Tetrahydropterin Synthetase (aka PTPS, PTS, 6-Pyruvoyl Tetrahydropterin Synthetase)

  • Sepiapterin Reductase (aka SR, Pyruvoyl tetrahydropterin reductase)

  • Pterin-4-alpha-carbinolamine dehydratase (aka PCD, PCBD, DCoH)

  • Dihydropteridine reductase (aka DHPR, Quinoid dihydropteridine reductase, QDPR)
    Enzymes directly involved in Serotonin & Dopamine synthesis in animals:
    Serotonin & Dopamine synthesis figure

  • Tryptophan hydroxylase (TPH)

  • Tyrosine hydroxylase (TH)

  • Aromatic L-amino acid decarboxylase / Dopa decarboxylase (AADC or DDC)
    Found in some plants, fungi and/or bacteria:
  • Tyrosine decarboxylase, Tryptophan decarboxylase, Phenylalanine decarboxylase
    Aromatic amino acid hydroxylases in animals (all require BH4 for function):
    AAAH reactions figure

  • Tryptophan hydroxylase (TPH), Tyrosine hydroxylase (TH), Phenylalanine hydroxylase (PAH)