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Reach

(4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin

362,296 routes · scope human · up to 3 steps · built 5 October 2026 · Reactions · API

Inferred

Every route here is a hypothesis drawn from reference reactions (Rhea and Human-GEM), not a finding. Currency species such as water, ATP and NAD(H) never form a step. Evidence key

253 compounds within 3 steps: 4 in 1, 47 in 2, 202 in 3

Does it reach a compound?

Two steps

1-O-(1,2-saturated-alkyl)-sn-glycerolReach from here →
1. (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin = (6R)-L-erythro-6,7-dihydrobiopterin + H2O
2. 1-O-(1,2-saturated-alkyl)-sn-glycerol + (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + O2 = a 1-(1-hydroxyalkyl)-sn-glycerol + (6R)-L-erythro-6,7-dihydrobiopterin + H2O
Catalysed by PCBD1, PCBD2, AGMO

Three steps

(S)-carnitineReach from here →
Catalysed by TPH1, TPH2, SLC6A14extracellular space, cytosol
CHEBI:1146900Reach from here →

Page 2 of 6

Catalysed by TPH1, TPH2, SLC7A5, BAAT

extracellular space, cytosol, peroxisome

One of 40 routes

N(omega)-methyl-L-arginineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
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 →

(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
transport of tryptophan and valine (cytosol to extracellular)
L-Valine:2-oxoglutarate aminotransferase

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

AReach from here →

(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
transport of cysteine and tryptophan (cytosol to extracellular)
Mo-molybdopterin + L-cysteine + AH2 = thio-Mo-molybdopterin + L-alanine + A + H2O

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

glycoursodeoxycholateReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
glycine to glycoursodeoxycholate conversion

Catalysed by TPH1, TPH2, SLC7A5extracellular space, cytosolOne of 2 routes

N-(9Z-octadecenoyl)glycineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
(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-leucineReach from here →

(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
transport of leucine and tryptophan (cytosol to extracellular)
N-(9Z-octadecenoyl)-L-leucine + H2O = L-leucine + (9Z)-octadecenoate

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

N-octadecanoylglycineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
octadecanoyl-CoA + glycine = N-octadecanoylglycine + CoA + H(+)

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

N-(9Z-hexadecenoyl)-glycineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
(9Z)-hexadecenoyl-CoA + glycine = N-(9Z-hexadecenoyl)-glycine + CoA + H(+)

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

N-hexadecanoylglycineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
hexadecanoyl-CoA + glycine = N-hexadecanoylglycine + CoA + H(+)

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

N-dodecanoylglycineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
dodecanoyl-CoA + glycine = N-dodecanoylglycine + CoA + H(+)

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

N-decanoylglycineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
decanoyl-CoA + glycine = N-decanoylglycine + CoA + H(+)

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

N-octanoylglycineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
octanoyl-CoA + glycine = N-octanoylglycine + CoA + H(+)

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

D-histidineReach from here →

(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
transport of ornithine and tryptophan (cytosol to extracellular)
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 →

(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
transport of arginine and tryptophan (cytosol to extracellular)
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 →

(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
transport of histidine and tryptophan (cytosol to extracellular)
Formation of homocarnosine

Catalysed by TPH1, TPH2, SLC7A6, CARNS1extracellular space, cytosolOne of 2 routes

N(1)-(5-phospho-beta-D-ribosyl)glycinamideReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
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 →

(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
transport of glycine and tryptophan (cytosol to extracellular)
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 →

(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
(6R)-L-erythro-5,6,7,8-tetrahydrobiopterin(out) + a dicarboxylate(in) = (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin(in) + a dicarboxylate(out)
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 →

(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
transport of glycine and tryptophan (cytosol to extracellular)
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 →

(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
transport of glutamine and tryptophan (cytosol to extracellular)
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

kinetensin-(1-8)Reach from here →

(6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-phenylalanine + O2 = (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tyrosine
Chymase
kinetensin + H2O = kinetensin-(1-8) + L-leucine

Catalysed by PAH, CMA1, ACE2extracellular space

an N-(fatty acyl)-glycineReach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
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 →

(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
transport of glycine and tryptophan (cytosol to extracellular)
(9Z,12Z)-octadecadienoyl-CoA + glycine = N-(9Z,12Z-octadecadienoyl)-glycine + CoA + H(+)

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

acetaldehydeReach from here →

(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
transport of threonine and tryptophan (cytosol to extracellular)
L-threonine acetaldehyde-lyase (glycine-forming)

Catalysed by TPH1, TPH2, SLC7A5extracellular space, cytosol

cholineReach from here →

(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
Transport of L-Tryptophan by Atb0 Transporter
transport of chloride and choline (cytosol to extracellular)

Catalysed by TPH1, TPH2, SLC6A14, SLC5A7extracellular space, cytosol

pyruvateReach from here →

(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
transport of alanine and tryptophan (cytosol to extracellular)
(R)-3-Amino-2-methylpropanoate:pyruvate aminotransferase

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

CHEBI:15570Reach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
transport of D-alanine and glycine (cytosol to extracellular)

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

CHEBI:15611Reach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
S-Adenosyl-L-methionine:glycine N-methyltransferase

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

trimethylenediamineReach from here →

(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
transport of lysine and tryptophan (cytosol to extracellular)
deoxyhypusine synthase (1,3-diaminopropane)

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

CHEBI:15727Reach from here →

(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
transport of histidine and tryptophan (cytosol to extracellular)
L-histidine:beta-alanine ligase (ADP-forming)

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

formateReach from here →

(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
L-tryptophan + O2 = N-formyl-L-kynurenine
N-formyl-L-kynurenine + H2O = L-kynurenine + formate + H(+)

Catalysed by TPH1, TPH2, IDO1, TDO2 and 2 more

CHEBI:15765Reach from here →

(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
transport of tryptophan and tyrosine (cytosol to extracellular)
L-Tyrosine,tetrahydrobiopterin:oxygen oxidoreductase (3-hydroxylating)

Catalysed by TPH1, TPH2, SLC7A5, THextracellular space, cytosolOne of 5 routes

4-(2-amino-3-hydroxyphenyl)-2,4-dioxobutanoateReach from here →

(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
Transport of 3-Hydroxy-L-Kynurenine
3-hydroxy-L-kynurenine:2-oxoglutarate aminotransferase

Catalysed by TPH1, TPH2, SLC7A5, KYAT1 and 2 moreextracellular space, cytosol

3-hydroxyanthranilic acidReach from here →

(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
Transport of 3-Hydroxy-L-Kynurenine
3-Hydroxy-L-kynurenine hydrolase

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

N-carbamoyl-L-aspartic acidReach from here →

(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
L-tryptophan(out) + L-aspartate(in) = L-tryptophan(in) + L-aspartate(out)
carbamoyl-phosphate:L-aspartate carbamoyltransferase

Catalysed by TPH1, TPH2, SLC7A13, CADinner side of the membrane, outer side of the membrane, cytosol

alpha-D-glucosamine 6-phosphateReach from here →

(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
transport of glutamine and tryptophan (cytosol to extracellular)
L-glutamine:D-fructose-6-phosphate isomerase (deaminating)

Catalysed by TPH1, TPH2, SLC7A5, GFPT2 and 1 moreextracellular space, cytosol

thioredoxin dithiolReach from here →

(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
L-Tryptophan -tRNA(Trp) ligase (AMP-forming)
glycyl-tRNA(gly) phosphorylation

Catalysed by TPH1, TPH2, WARS1cytosolOne of 4 routes

sulfateReach from here →

(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
Transport of L-Tryptophan by Atb0 Transporter
transport of chloride and sulfate (cytosol to extracellular)

Catalysed by TPH1, TPH2, SLC6A14, SLC26A6extracellular space, cytosolOne of 5 routes

ureaReach from here →

(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
transport of arginine and tryptophan (cytosol to extracellular)
L-Arginine amidinohydrolase

Catalysed by TPH1, TPH2, SLC7A6, ARG1extracellular space, cytosolOne of 3 routes

L-cystineReach from here →

(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
transport of alanine and tryptophan (cytosol to extracellular)
Transport of L-Cystine (L-Alanine antiport) by B0, +At Transporter

Catalysed by TPH1, TPH2, SLC7A5, SLC7A9 and 1 moreextracellular space, cytosolOne of 9 routes

(R)-3-aminoisobutyric acidReach from here →

(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
transport of alanine and tryptophan (cytosol to extracellular)
(R)-3-Amino-2-methylpropanoate:pyruvate aminotransferase

Catalysed by TPH1, TPH2, SLC7A5, AGXT2extracellular space, cytosol, mitochondrial matrix

iodideReach from here →

(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
transport of tryptophan and tyrosine (cytosol to extracellular)
thyroid peroxidase (iodine)

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

2-phenylacetaldehydeReach from here →

(6R)-L-erythro-5,6,7,8-tetrahydrobiopterin + L-phenylalanine + O2 = (4aS,6R)-4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin + L-tyrosine
L-phenylalanine carboxy-lyase (phenylethylamine-forming)
Phenethylamine:oxygen oxidoreductase (deaminating)

Catalysed by PAH, DDC, AOC2, AOC1 and 3 morecytosolOne of 2 routes

oxaloacetateReach from here →

(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
L-tryptophan(out) + L-aspartate(in) = L-tryptophan(in) + L-aspartate(out)
L-Aspartate:2-oxoglutarate aminotransferase

Catalysed by TPH1, TPH2, SLC7A13, GOT2inner side of the membrane, outer side of the membrane, mitochondrial matrixOne of 5 routes

nitric oxideReach from here →

(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
transport of arginine and tryptophan (cytosol to extracellular)
L-Arginine, NADPH:Oxygen Oxidoreductase (Nitric-Oxide-Forming)

Catalysed by TPH1, TPH2, SLC7A6, NOS3 and 2 moreextracellular space, cytosolOne of 2 routes

CHEBI:16523Reach from here →

(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
transport of glycine and tryptophan (cytosol to extracellular)
transport of D-serine and glycine (cytosol to extracellular)

Catalysed by TPH1, TPH2, SLC7A5, SLC3A2 and 1 moreextracellular space, cytosolOne of 4 routes

N(2)-acetyl-L-ornithineReach from here →

(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
transport of ornithine and tryptophan (cytosol to extracellular)
N2-Acetyl-L-ornithine amidohydrolase

Catalysed by TPH1, TPH2, SLC7A6, ACY1extracellular space, cytosol