5-hydroxy-L-tryptophan

Three steps

• N(omega)-methyl-L-arginineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. N(omega)-methyl-L-arginine + glyoxylate = 5-(3-methylguanidino)-2-oxopentanoate + glycine

  Catalysed by TPH1, TPH2, SLC7A5, AGXT2extracellular space, cytosolOne of 4 routes

• 3-methyl-2-oxobutanoateReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of tryptophan and valine (cytosol to extracellular)
  3. L-Valine:2-oxoglutarate aminotransferase

  Catalysed by TPH1, TPH2, SLC7A5, BCAT2extracellular space, cytosol, mitochondrial matrixOne of 3 routes

• AReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of cysteine and tryptophan (cytosol to extracellular)
  3. Mo-molybdopterin + L-cysteine + AH2 = thio-Mo-molybdopterin + L-alanine + A + H2O

  Catalysed by TPH1, TPH2, SLC7A5, MOCOSextracellular space, cytosol

• tauroursodeoxycholateReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. transport of serotonin (cytosol to extracellular)
  3. transport of S-glutathionyl-2-4-dinitrobenzene (cytosol to extracellular)

  Catalysed by DDC, SLCO1A2, SLCO1B3extracellular space, cytosolOne of 4 routes

• glycoursodeoxycholateReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. glycine to glycoursodeoxycholate conversion

  Catalysed by TPH1, TPH2, SLC7A5extracellular space, cytosolOne of 6 routes

• (11S,15S)-dihydroxy-14(R)-S-glutathionyl-(5Z,8Z,12E)-eicosatrienoateReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. transport of GSH and serotonin (cytosol to extracellular)
  3. glutathione transferase (GSH)

  Catalysed by DDC, SLCO1A2, SLCO1B3, PTGES and 20 moreextracellular space, cytosolOne of 4 routes

• prostaglandin E3Reach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. transport of serotonin (cytosol to extracellular)
  3. transport of prostaglandin E3 (cytosol to extracellular)

  Catalysed by DDC, SLCO1A2, SLCO1B3, SLCO1B1extracellular space, cytosolOne of 4 routes

• prostaglandin A2Reach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. transport of serotonin (cytosol to extracellular)
  3. transport of prostaglandin A2 (cytosol to extracellular)

  Catalysed by DDC, SLCO1A2, SLCO1B3, SLCO1B1extracellular space, cytosolOne of 4 routes

• prostaglandin B1Reach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. transport of serotonin (cytosol to extracellular)
  3. transport of prostaglandin B1 (cytosol to extracellular)

  Catalysed by DDC, SLCO1A2, SLCO1B3, SLCO1B1extracellular space, cytosolOne of 4 routes

• leukotriene F4Reach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. transport of serotonin (cytosol to extracellular)
  3. transport of leukotriene F4 (cytosol to extracellular)

  Catalysed by DDC, SLCO1A2, SLCO1B3, SLCO1B1extracellular space, cytosolOne of 4 routes

• N-(9Z-octadecenoyl)glycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. (9Z)-octadecenoyl-CoA + glycine = N-(9Z-octadecenoyl)glycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL3 and 1 moreextracellular space, cytosol

• N-(9Z-octadecenoyl)-L-phenylalanineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of phenylalanine and tryptophan (cytosol to extracellular)
  3. L-phenylalanine + (9Z)-octadecenoate = N-(9Z-octadecenoyl)-L-phenylalanine + H2O

  Catalysed by TPH1, TPH2, SLC7A5, PM20D1extracellular space, cytosol

• N-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-L-phenylalanineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of phenylalanine and tryptophan (cytosol to extracellular)
  3. (5Z,8Z,11Z,14Z)-eicosatetraenoate + L-phenylalanine = N-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-L-phenylalanine + H2O

  Catalysed by TPH1, TPH2, SLC7A5, PM20D1extracellular space, cytosol

• N-(9Z-octadecenoyl)-L-leucineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of leucine and tryptophan (cytosol to extracellular)
  3. N-(9Z-octadecenoyl)-L-leucine + H2O = L-leucine + (9Z)-octadecenoate

  Catalysed by TPH1, TPH2, SLC7A5, PM20D1extracellular space, cytosol

• N-octadecanoylglycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. octadecanoyl-CoA + glycine = N-octadecanoylglycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL2extracellular space, cytosol

• N-(9Z-hexadecenoyl)-glycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. (9Z)-hexadecenoyl-CoA + glycine = N-(9Z-hexadecenoyl)-glycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL2extracellular space, cytosol

• N-hexadecanoylglycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. hexadecanoyl-CoA + glycine = N-hexadecanoylglycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL3extracellular space, cytosol

• N-dodecanoylglycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. dodecanoyl-CoA + glycine = N-dodecanoylglycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL2extracellular space, cytosol

• N-decanoylglycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. decanoyl-CoA + glycine = N-decanoylglycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL2extracellular space, cytosol

• N-octanoylglycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. octanoyl-CoA + glycine = N-octanoylglycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL2extracellular space, cytosol

• D-histidineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of ornithine and tryptophan (cytosol to extracellular)
  3. D-histidine(in) + L-ornithine(out) + H(+)(in) = D-histidine(out) + L-ornithine(in) + H(+)(out)

  Catalysed by TPH1, TPH2, SLC7A6, SLC25A2extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 2 routes

• L-homoarginineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of arginine and tryptophan (cytosol to extracellular)
  3. L-homoarginine(in) + L-arginine(out) = L-homoarginine(out) + L-arginine(in)

  Catalysed by TPH1, TPH2, SLC7A6, SLC25A29extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 4 routes

• L-homocarnosineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of histidine and tryptophan (cytosol to extracellular)
  3. Formation of homocarnosine

  Catalysed by TPH1, TPH2, SLC7A6, CARNS1extracellular space, cytosol

• N(1)-(5-phospho-beta-D-ribosyl)glycinamideReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. 5-phospho-beta-D-ribosylamine + glycine + ATP = N(1)-(5-phospho-beta-D-ribosyl)glycinamide + ADP + phosphate + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GARTextracellular space, cytosol

• L-cystine-bis-glycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. L-cystine-bis-glycine + 2 H2O = L-cystine + 2 glycine

  Catalysed by TPH1, TPH2, SLC7A5, DPEP1 and 1 moreextracellular space, cytosol

• indoxyl sulfateReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin(out) + a dicarboxylate(in) = (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin(in) + a dicarboxylate(out)
  3. indoxyl sulfate(out) + a dicarboxylate(in) = indoxyl sulfate(in) + a dicarboxylate(out)

  Catalysed by TPH1, TPH2, SLC22A6, SLC22A8inner side of the membrane, outer side of the membraneOne of 2 routes

• glycyldehydrophenylalanineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. glycyldehydrophenylalanine + H2O = 2,3-didehydrophenylalanine + glycine

  Catalysed by TPH1, TPH2, SLC7A5, DPEP1extracellular space, cytosol

• 2-formamido-N(1)-(5-O-phospho-beta-D-ribosyl)acetamidineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glutamine and tryptophan (cytosol to extracellular)
  3. N(2)-formyl-N(1)-(5-phospho-beta-D-ribosyl)glycinamide + L-glutamine + ATP + H2O = 2-formamido-N(1)-(5-O-phospho-beta-D-ribosyl)acetamidine + L-glutamate + ADP + phosphate + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, PFASextracellular space, cytosol

• kinetensinReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of phenylalanine and tryptophan (cytosol to extracellular)
  3. Chymase

  Catalysed by TPH1, TPH2, SLC7A5, CMA1extracellular space, cytosolOne of 3 routes

• an N-(fatty acyl)-glycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. a fatty acyl-CoA + glycine = an N-(fatty acyl)-glycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL2extracellular space, cytosol

• N-(9Z,12Z-octadecadienoyl)-glycineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. (9Z,12Z)-octadecadienoyl-CoA + glycine = N-(9Z,12Z-octadecadienoyl)-glycine + CoA + H(+)

  Catalysed by TPH1, TPH2, SLC7A5, GLYATL2extracellular space, cytosol

• (7Z)-octadecenoyl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. carnitine O-palmitoyltransferase ((7Z)-octadecenoyl-CoA)

  Catalysed by DDC, AANAT, CPT1A, CPT1C and 1 morecytosolOne of 3 routes

• acetaldehydeReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of threonine and tryptophan (cytosol to extracellular)
  3. L-threonine acetaldehyde-lyase (glycine-forming)

  Catalysed by TPH1, TPH2, SLC7A5extracellular space, cytosol

• CHEBI:15345Reach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. Acetoacetate:CoA ligase (AMP-forming)

  Catalysed by DDC, AANAT, AACScytosolOne of 2 routes

• cholineReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. Transport of L-Tryptophan by Atb0 Transporter
  3. transport of chloride and choline (cytosol to extracellular)

  Catalysed by TPH1, TPH2, SLC6A14, SLC5A7extracellular space, cytosolOne of 2 routes

• acetylcholineReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. transport of serotonin (cytosol to extracellular)
  3. transport of acetylcholine (cytosol to extracellular)

  Catalysed by DDC, SLCO1A2, SLCO1B3extracellular space, cytosolOne of 4 routes

• pyruvateReach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of alanine and tryptophan (cytosol to extracellular)
  3. (R)-3-Amino-2-methylpropanoate:pyruvate aminotransferase

  Catalysed by TPH1, TPH2, SLC7A5, AGXT2extracellular space, cytosol, mitochondrial matrixOne of 16 routes

• CHEBI:15380Reach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. 5-aminolevulinate synthase (2-amino-3-oxoadipate)

  Catalysed by DDC, AANAT, ALAS1, CPNE7cytosol, mitochondrial matrixOne of 8 routes

• CHEBI:15477Reach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. glycine N-acyltransferase (2-methylbutyryl-CoA)

  Catalysed by DDC, AANAT, GLYAT, GLYATL2 and 1 morecytosol, mitochondrial matrixOne of 2 routes

• 2-methylcrotonoyl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. Production of Tiglylcarnitine

  Catalysed by DDC, AANAT, CPT1A, CPT1BcytosolOne of 2 routes

• isobutyryl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. acetyl-CoA C-acyltransferase (3-oxo-4-methyl-pentanoyl-CoA)

  Catalysed by DDC, AANAT, HADHA, ACAA2 and 1 morecytosol, mitochondrial matrixOne of 3 routes

• 3-methylbut-2-enoyl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. glycine-N-acyltransferase (3-methylcrotonoylglycine)

  Catalysed by DDC, AANAT, GLYATcytosol, mitochondrial matrix

• isovaleryl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. glycine N-acyltransferase (isovalerylglycine)

  Catalysed by DDC, AANAT, GLYAT, GLYATL2 and 1 morecytosol, mitochondrial matrixOne of 3 routes

• arachidonoyl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. Arachidonate:CoA ligase (AMP-forming)

  Catalysed by DDC, AANAT, SLC27A2, ACSL4 and 6 morecytosolOne of 11 routes

• CHEBI:15519Reach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. propanoyl-CoA C-acyltransferase

  Catalysed by DDC, AANAT, ACAA1, SCP2 and 1 morecytosol, peroxisomeOne of 2 routes

• palmitoyl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. Palmitate:CoA ligase (AMP-forming)

  Catalysed by DDC, AANAT, SLC27A2, ACSL4 and 6 morecytosolOne of 11 routes

• oleoyl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. Transport of octadecenoyl-CoA into Mitochondrial Matrix

  Catalysed by DDC, AANAT, CPT1A, CPT1C and 1 morecytosolOne of 11 routes

• phenylacetyl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. Phenylacetate:CoA ligase

  Catalysed by DDC, AANATcytosolOne of 3 routes

• propionyl-CoAReach from here →
  1. 5-hydroxy-L-tryptophan + H(+) = serotonin + CO2
  2. acetyl-CoA:aralkylamine N-acetyltransferase
  3. Propanoate:CoA ligase (AMP-forming)

  Catalysed by DDC, AANAT, ACSS3, ACSS2 and 1 morecytosolOne of 43 routes

• CHEBI:15570Reach from here →
  1. (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tryptophan + O2 = 5-hydroxy-L-tryptophan + (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin
  2. transport of glycine and tryptophan (cytosol to extracellular)
  3. transport of D-alanine and glycine (cytosol to extracellular)

  Catalysed by TPH1, TPH2, SLC7A5, SLC3A2 and 1 moreextracellular space, cytosolOne of 5 routes