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Reach

AH2

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

574 compounds within 3 steps: 59 in 1, 98 in 2, 417 in 3

Does it reach a compound?

Two steps

Fe(II)-heme aReach from here →
1. A + NADH + H(+) = AH2 + NAD(+)
2. Fe(II)-heme o + 2 A + H2O = Fe(II)-heme a + 2 AH2
Catalysed by AIFM1, PYROXD1, COX15
Mo-molybdopterinReach from here →
1. A + NADH + H(+) = AH2 + NAD(+)
2. Mo-molybdopterin + L-cysteine + AH2 = thio-Mo-molybdopterin + L-alanine + A + H2O
Catalysed by AIFM1, PYROXD1, MOCOSOne of 3 routes
(2S)-2-aminobutanoateReach from here →
1. L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
2. 2-oxobutanoate + L-alanine = (2S)-2-aminobutanoate + pyruvate
Catalysed by SCLY, AGXT2
(12S)-hydroxy-(5Z,8E,10E)-heptadecatrienoateReach from here →
1. (5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 O2 = prostaglandin H2 + A + H2O
2. prostaglandin H2 = (12S)-hydroxy-(5Z,8E,10E)-heptadecatrienoate + malonaldehyde
Catalysed by PTGS1, PTGS2, TBXAS1, CYP2S1 and 1 more
11-oxo-(5Z,8Z,12E,14Z)-eicosatetraenoateReach from here →
1. (5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + O2 = (11R)-hydroxy-(5Z,8Z,12E,14Z)-eicosatetraenoate + A + H2O
2. (11R)-hydroxy-(5Z,8Z,12E,14Z)-eicosatetraenoate + NAD(+) = 11-oxo-(5Z,8Z,12E,14Z)-eicosatetraenoate + NADH + H(+)
Catalysed by PTGS2, HPGD
19-hydroxyprostaglandin H2Reach from here →
1. (5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 O2 = prostaglandin H2 + A + H2O
2. prostaglandin H2 + reduced [NADPH--hemoprotein reductase] + O2 = 19-hydroxyprostaglandin H2 + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
Catalysed by PTGS1, PTGS2, CYP4F8
19-hydroxyprostaglandin H1Reach from here →
1. prostaglandin G1 + AH2 = prostaglandin H1 + A + H2O
2. prostaglandin H1 + reduced [NADPH--hemoprotein reductase] + O2 = 19-hydroxyprostaglandin H1 + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
Catalysed by PTGS2, CYP4F8

Three steps

beta-carbolineReach from here →
Catalysed by SCLY, SLC7A5extracellular space, cytosol
(S)-carnitineReach from here →
Catalysed by SCLY, CPT1A

Page 4 of 12

, CPT1C

, CPT1B

mitochondrial matrix, cytosol

One of 245 routes

2-hydroxybutyric acidReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
(R)-3-Amino-2-methylpropanoate:pyruvate aminotransferase
transport of 2-hydroxybutyrate and pyruvate (cytosol to extracellular)

Catalysed by SCLY, AGXT2, SLC16A4, SLC16A5 and 4 moremitochondrial matrix, extracellular space, cytosolOne of 2 routes

3-methyl-2-oxobutanoateReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and valine (cytosol to extracellular)
L-Valine:2-oxoglutarate aminotransferase

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

tauroursodeoxycholateReach from here →

3,3',5-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
transport of GSH and triiodothyronine (cytosol to extracellular)
transport of GSH and tauroursodeoxycholate (cytosol to extracellular)

Catalysed by DIO1, DIO2, SLCO1A2, SLCO1B3extracellular space, cytosolOne of 4 routes

glycoursodeoxycholateReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
glycine to glycoursodeoxycholate conversion

Catalysed by SCLY, AGXT, AGXT2mitochondrial matrix, cytosolOne of 6 routes

(11S,15S)-dihydroxy-14(R)-S-glutathionyl-(5Z,8Z,12E)-eicosatrienoateReach from here →

3,3',5-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
transport of GSH and triiodothyronine (cytosol to extracellular)
glutathione transferase (GSH)

Catalysed by DIO1, DIO2, SLCO1A2, SLCO1B3 and 21 moreextracellular space, cytosolOne of 4 routes

(5S,6S)-epoxy-(18R)-hydroxy-(7E,9E,11Z,14Z,16E)-eicosapentaenoateReach from here →

(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate + AH2 + O2 = (18R)-hydroxy-(5Z,8Z,11Z,14Z,16E)-eicosapentaenoate + A + H2O
(18R)-hydroxy-(5Z,8Z,11Z,14Z,16E)-eicosapentaenoate + O2 = (5S)-hydroperoxy-(18R)-hydroxy-(6E,8Z,11Z,14Z,16E)-eicosapentaenoate
(5S)-hydroperoxy-(18R)-hydroxy-(6E,8Z,11Z,14Z,16E)-eicosapentaenoate = (5S,6S)-epoxy-(18R)-hydroxy-(7E,9E,11Z,14Z,16E)-eicosapentaenoate + H2O

Catalysed by PTGS2, ALOX5

all-trans-3,4-didehydroretinolReach from here →

A + NADH + H(+) = AH2 + NAD(+)
all-trans-13,14-dihydroretinol + A = all-trans-retinol + AH2
all-trans-retinol + 2 reduced [adrenodoxin] + O2 + 2 H(+) = all-trans-3,4-didehydroretinol + 2 oxidized [adrenodoxin] + 2 H2O

Catalysed by AIFM1, PYROXD1, RETSAT, CYP27C1

all-trans-4-hydroxyretinolReach from here →

A + NADH + H(+) = AH2 + NAD(+)
all-trans-13,14-dihydroretinol + A = all-trans-retinol + AH2
all-trans-retinol + 2 reduced [adrenodoxin] + O2 + 2 H(+) = all-trans-4-hydroxyretinol + 2 oxidized [adrenodoxin] + H2O

Catalysed by AIFM1, PYROXD1, RETSAT, CYP27C1

pregnenolone sulfateReach from here →

3,3'-diiodo-L-thyronine sulfate + iodide + A + H(+) = 3,3',5-triiodo-L-thyronine sulfate + AH2
Steryl-Sulfatase
Steryl-Sulfatase

Catalysed by DIO1, STSGolgi apparatusOne of 2 routes

androsterone 3alpha-sulfateReach from here →

3,3'-diiodo-L-thyronine sulfate + iodide + A + H(+) = 3,3',5-triiodo-L-thyronine sulfate + AH2
Steryl-Sulfatase
steroid sulfatase (androsterone sulfate)

Catalysed by DIO1, STSGolgi apparatus, cytosolOne of 3 routes

prostaglandin E3Reach from here →

3,3',5-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
transport of GSH and triiodothyronine (cytosol to extracellular)
transport of GSH and prostaglandin E3 (cytosol to extracellular)

Catalysed by DIO1, DIO2, SLCO1A2, SLCO1B3 and 1 moreextracellular space, cytosolOne of 6 routes

prostaglandin A2Reach from here →

3,3',5-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
transport of GSH and triiodothyronine (cytosol to extracellular)
transport of GSH and prostaglandin A2 (cytosol to extracellular)

Catalysed by DIO1, DIO2, SLCO1A2, SLCO1B3 and 1 moreextracellular space, cytosolOne of 6 routes

prostaglandin B1Reach from here →

3,3',5-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
transport of GSH and triiodothyronine (cytosol to extracellular)
transport of GSH and prostaglandin B1 (cytosol to extracellular)

Catalysed by DIO1, DIO2, SLCO1A2, SLCO1B3 and 1 moreextracellular space, cytosolOne of 4 routes

prostaglandin J2Reach from here →

(5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 O2 = prostaglandin H2 + A + H2O
prostaglandin-D synthase (prostaglandin H2)
prostaglandin J2 hydrolysis

Catalysed by PTGS1, PTGS2, HPGDS, PTGDScytosolOne of 2 routes

15-oxoprostaglandin F2alphaReach from here →

(5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 O2 = prostaglandin H2 + A + H2O
prostaglandin I2 synthase (prostaglandin H2)
Formation of Prostaglandin I2

Catalysed by PTGS1, PTGS2, PTGISendoplasmic reticulum, cytosolOne of 4 routes

leukotriene F4Reach from here →

3,3',5-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
transport of GSH and triiodothyronine (cytosol to extracellular)
transport of GSH and leukotriene F4 (cytosol to extracellular)

Catalysed by DIO1, DIO2, SLCO1A2, SLCO1B3extracellular space, cytosolOne of 4 routes

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

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
(9Z)-octadecenoyl-CoA + glycine = N-(9Z-octadecenoyl)glycine + CoA + H(+)

Catalysed by SCLY, AGXT, AGXT2, GLYATL3 and 1 moremitochondrial matrix

N-(9Z-octadecenoyl)-L-phenylalanineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and phenylalanine (cytosol to extracellular)
L-phenylalanine + (9Z)-octadecenoate = N-(9Z-octadecenoyl)-L-phenylalanine + H2O

Catalysed by SCLY, SLC7A5, PM20D1extracellular space, cytosol

N-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-L-phenylalanineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and phenylalanine (cytosol to extracellular)
(5Z,8Z,11Z,14Z)-eicosatetraenoate + L-phenylalanine = N-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-L-phenylalanine + H2O

Catalysed by SCLY, SLC7A5, PM20D1extracellular space, cytosol

N-(9Z-octadecenoyl)-L-leucineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and leucine (cytosol to extracellular)
N-(9Z-octadecenoyl)-L-leucine + H2O = L-leucine + (9Z)-octadecenoate

Catalysed by SCLY, SLC7A5, PM20D1extracellular space, cytosol

N-octadecanoylglycineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
octadecanoyl-CoA + glycine = N-octadecanoylglycine + CoA + H(+)

Catalysed by SCLY, AGXT, AGXT2, GLYATL2mitochondrial matrix

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

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
(9Z)-hexadecenoyl-CoA + glycine = N-(9Z-hexadecenoyl)-glycine + CoA + H(+)

Catalysed by SCLY, AGXT, AGXT2, GLYATL2mitochondrial matrix

(5S,6S)-epoxy-(18S)-hydroxy-(7E,9E,11Z,14Z,16E)-eicosapentaenoateReach from here →

(5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate + AH2 + O2 = (18S)-hydroxy-(5Z,8Z,11Z,14Z,16E)-eicosapentaenoate + A + H2O
(18S)-hydroxy-(5Z,8Z,11Z,14Z,16E)-eicosapentaenoate + O2 = (5S)-hydroperoxy-(18S)-hydroxy-(6E,8Z,11Z,14Z,16E)-eicosapentaenoate
(5S)-hydroperoxy-(18S)-hydroxy-(6E,8Z,11Z,14Z,16E)-eicosapentaenoate = (5S,6S)-epoxy-(18S)-hydroxy-(7E,9E,11Z,14Z,16E)-eicosapentaenoate + H2O

Catalysed by PTGS2, ALOX5

cholesterol sulfateReach from here →

3,3'-diiodo-L-thyronine sulfate + iodide + A + H(+) = 3,3',5-triiodo-L-thyronine sulfate + AH2
Steryl-Sulfatase
Steryl-Sulfatase

Catalysed by DIO1, STSGolgi apparatusOne of 2 routes

5alpha-dihydrotestosterone sulfateReach from here →

3,3'-diiodo-L-thyronine sulfate + iodide + A + H(+) = 3,3',5-triiodo-L-thyronine sulfate + AH2
Steryl-Sulfatase
steroid sulfatase (5-alpha-dihydrotestosterone)

Catalysed by DIO1, STSGolgi apparatus, cytosolOne of 3 routes

acetoacetateReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
(R)-3-Amino-2-methylpropanoate:pyruvate aminotransferase
transport of acetoacetate and pyruvate (cytosol to mitochondria)

Catalysed by SCLY, AGXT2mitochondrial matrix, cytosolOne of 4 routes

N-(4-oxoglutaryl)-L-cysteinylglycineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
gamma-glutamyltransferase (alanine)
N-(4-oxoglutaryl)-L-cysteinylglycine + H2O = L-cysteinylglycine + 2-oxoglutarate

Catalysed by SCLY, GGTLC3, GGT1, GGT5 and 4 morecytosol

all-trans-retinyl tetradecanoateReach from here →

A + NADH + H(+) = AH2 + NAD(+)
all-trans-13,14-dihydroretinol + A = all-trans-retinol + AH2
all-trans-retinol + tetradecanoyl-CoA = all-trans-retinyl tetradecanoate + CoA

Catalysed by AIFM1, PYROXD1, RETSAT, AWAT2

an aryl sulfateReach from here →

3,3'-diiodo-L-thyronine sulfate + iodide + A + H(+) = 3,3',5-triiodo-L-thyronine sulfate + AH2
Steryl-Sulfatase
an aryl sulfate + H2O = a phenol + sulfate + H(+)

Catalysed by DIO1, STS, ARSL, ARSF and 4 moreGolgi apparatus

N-hexadecanoylglycineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
hexadecanoyl-CoA + glycine = N-hexadecanoylglycine + CoA + H(+)

Catalysed by SCLY, AGXT, AGXT2, GLYATL3mitochondrial matrix

N-dodecanoylglycineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
dodecanoyl-CoA + glycine = N-dodecanoylglycine + CoA + H(+)

Catalysed by SCLY, AGXT, AGXT2, GLYATL2mitochondrial matrix

N-decanoylglycineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
decanoyl-CoA + glycine = N-decanoylglycine + CoA + H(+)

Catalysed by SCLY, AGXT, AGXT2, GLYATL2mitochondrial matrix

N-octanoylglycineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
octanoyl-CoA + glycine = N-octanoylglycine + CoA + H(+)

Catalysed by SCLY, AGXT, AGXT2, GLYATL2mitochondrial matrix

D-histidineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and ornithine (cytosol to extracellular)
D-histidine(in) + L-ornithine(out) + H(+)(in) = D-histidine(out) + L-ornithine(in) + H(+)(out)

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

L-homoarginineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and arginine (cytosol to extracellular)
L-homoarginine(in) + L-arginine(out) = L-homoarginine(out) + L-arginine(in)

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

L-homocarnosineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and histidine (cytosol to extracellular)
Formation of homocarnosine

Catalysed by SCLY, SLC7A6, CARNS1extracellular space, cytosol

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

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
5-phospho-beta-D-ribosylamine + glycine + ATP = N(1)-(5-phospho-beta-D-ribosyl)glycinamide + ADP + phosphate + H(+)

Catalysed by SCLY, AGXT, AGXT2, GARTmitochondrial matrix

L-cystine-bis-glycineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
L-cystine-bis-glycine + 2 H2O = L-cystine + 2 glycine

Catalysed by SCLY, AGXT, AGXT2, DPEP1 and 1 moremitochondrial matrixOne of 3 routes

glycyldehydrophenylalanineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:glyoxylate aminotransferase
glycyldehydrophenylalanine + H2O = 2,3-didehydrophenylalanine + glycine

Catalysed by SCLY, AGXT, AGXT2, DPEP1mitochondrial matrix

2-formamido-N(1)-(5-O-phospho-beta-D-ribosyl)acetamidineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and glutamine (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 SCLY, SLC3A2, SLC7A5, SLC7A10 and 1 moreextracellular space, cytosol

kinetensinReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
transport of alanine and phenylalanine (cytosol to extracellular)
Chymase

Catalysed by SCLY, SLC7A5, CMA1extracellular space, cytosolOne of 3 routes