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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?

One step

(5S,15R)-dihydroxy-(6E,8Z,11Z,13E)-eicosatetraenoateReach from here →
1. (5S)-hydroxy-(6E,8Z,11Z,14Z)-eicosatetraenoate + AH2 + O2 = (5S,15R)-dihydroxy-(6E,8Z,11Z,13E)-eicosatetraenoate + A + H2O
Catalysed by PTGS2
(5S,15S)-dihydroxy-(6E,8Z,11Z,13E)-eicosatetraenoateReach from here →
1. (5S)-hydroxy-(6E,8Z,11Z,14Z)-eicosatetraenoate + AH2 + O2 = (5S,15S)-dihydroxy-(6E,8Z,11Z,13E)-eicosatetraenoate + A + H2O
Catalysed by PTGS2
17R-hydroxy-(4Z,7Z,10Z,13Z,15E,19Z)-docosahexaenoateReach from here →
1. (4Z,7Z,10Z,13Z,16Z,19Z)-docosahexaenoate + AH2 + O2 = 17R-hydroxy-(4Z,7Z,10Z,13Z,15E,19Z)-docosahexaenoate + A + H2O
Catalysed by PTGS2
13-hydroxy-(4Z,7Z,10Z,14E,16Z,19Z)-docosahexaenoateReach from here →
1. (4Z,7Z,10Z,13Z,16Z,19Z)-docosahexaenoate + AH2 + O2 = 13-hydroxy-(4Z,7Z,10Z,14E,16Z,19Z)-docosahexaenoate + A + H2O
Catalysed by PTGS2
(18R)-hydroxy-(5Z,8Z,11Z,14Z,16E)-eicosapentaenoateReach from here →
1. (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate + AH2 + O2 = (18R)-hydroxy-(5Z,8Z,11Z,14Z,16E)-eicosapentaenoate + A + H2O
Catalysed by PTGS2
(15R)-hydroxy-(5Z,8Z,11Z,13E,17Z)-eicosapentaenoateReach from here →
1. (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate + AH2 + O2 = (15R)-hydroxy-(5Z,8Z,11Z,13E,17Z)-eicosapentaenoate + A + H2O
Catalysed by PTGS2
(11R)-hydroxy-(5Z,8Z,12E,14Z,17Z)-eicosapentaenoateReach from here →
1. (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate + AH2 + O2 = (11R)-hydroxy-(5Z,8Z,12E,14Z,17Z)-eicosapentaenoate + A + H2O
Catalysed by PTGS2
13R-hydroxy-(7Z,10Z,14E,16Z,19Z)-docosapentaenoateReach from here →
1. (7Z,10Z,13Z,16Z,19Z)-docosapentaenoate + AH2 + O2 = 13R-hydroxy-(7Z,10Z,14E,16Z,19Z)-docosapentaenoate + A + H2O
Catalysed by PTGS2
(13S)-hydroxy-(9Z,11E)-octadecadienoateReach from here →
1. (9Z,12Z)-octadecadienoate + AH2 + O2 = (13S)-hydroxy-(9Z,11E)-octadecadienoate + A + H2O
Catalysed by PTGS1, PTGS2

Two steps

CHEBI:1146900Reach from here →
1. L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
2. amino-acid N-acetyltransferase (N-acetyl-L-alanine)
Catalysed by SCLYmitochondrial matrixOne of 2 routes
N(omega)-methyl-L-arginineReach from here →
1. L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
2. N(omega)-methyl-L-arginine + pyruvate = 5-(3-methylguanidino)-2-oxopentanoate + L-alanine
Catalysed by SCLY, AGXT2
(5S)-hydroperoxy-(15S)-hydroxy-(6E,8Z,11Z,13E)-eicosatetraenoateReach from here →

Page 2 of 12

(15S)-hydroperoxy-(5Z,8Z,11Z,13E)-eicosatetraenoate + AH2 = (15S)-hydroxy-(5Z,8Z,11Z,13E)-eicosatetraenoate + A + H2O
(15S)-hydroxy-(5Z,8Z,11Z,13E)-eicosatetraenoate + O2 = (5S)-hydroperoxy-(15S)-hydroxy-(6E,8Z,11Z,13E)-eicosatetraenoate

Catalysed by TBXAS1, PTGS2, PTGIS, ALOX5

(5S)-hydroperoxy-(18S)-hydroxy-(6E,8Z,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

Catalysed by PTGS2, ALOX5

(5S)-hydroperoxy-(18R)-hydroxy-(6E,8Z,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

Catalysed by PTGS2, ALOX5

2,4-dinitrophenyl-S-glutathioneReach from here →

3,3',5-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
transport of S-glutathionyl-2-4-dinitrobenzene (cytosol to extracellular)

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

2-glyceryl-prostaglandin D2Reach from here →

2-glyceryl-prostaglandin G2 + AH2 = 2-glyceryl-prostaglandin H2 + A + H2O
2-glyceryl-prostaglandin H2 = 2-glyceryl-prostaglandin D2

Catalysed by PTGS2, HPGDS

2-glyceryl-prostaglandin E2Reach from here →

2-glyceryl-prostaglandin G2 + AH2 = 2-glyceryl-prostaglandin H2 + A + H2O
2-glyceryl-prostaglandin H2 = 2-glyceryl-prostaglandin E2

Catalysed by PTGS2, PTGES

pyruvateReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
(R)-3-Amino-2-methylpropanoate:pyruvate aminotransferase

Catalysed by SCLY, AGXT2mitochondrial matrixOne of 14 routes

CHEBI:15570Reach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
alanine racemase

Catalysed by SCLYcytosol

L-leucineReach from here →

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

Catalysed by SCLY, SLC7A5extracellular space, cytosolOne of 10 routes

15(S)-HPETEReach from here →

(15S)-hydroperoxy-(5Z,8Z,11Z,13E)-eicosatetraenoate + AH2 = (15S)-hydroxy-(5Z,8Z,11Z,13E)-eicosatetraenoate + A + H2O
Glutathione: 15-HPETE oxidoreductase

Catalysed by TBXAS1, PTGS2, PTGIS, GPX5 and 8 morecytosolOne of 2 routes

CHEBI:15699Reach from here →

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

Catalysed by SCLY, SLC7A5extracellular space, cytosolOne of 6 routes

betaine aldehydeReach from here →

A + NADH + H(+) = AH2 + NAD(+)
choline + A = betaine aldehyde + AH2

Catalysed by AIFM1, PYROXD1, CHDH

CHEBI:15971Reach from here →

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

Catalysed by SCLY, SLC7A6extracellular space, cytosolOne of 4 routes

selenophosphateReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
hydrogenselenide + ATP + H2O = selenophosphate + AMP + phosphate + 2 H(+)

Catalysed by SCLY, SEPHS1, SEPHS2

sulfateReach from here →

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

Catalysed by DIO1, STSGolgi apparatusOne of 3 routes

L-cystineReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
Transport of L-Cystine (L-Alanine antiport) by B0, +At Transporter

Catalysed by SCLY, SLC7A9, SLC3A1extracellular space, cytosol

nitriteReach from here →

2 nitrite + AH2 + 2 H(+) = 2 nitric oxide + A + 2 H2O
4 nitric oxide + O2 + 2 H2O = 4 nitrite + 4 H(+)

Catalysed by SUOX, CP

(R)-3-aminoisobutyric acidReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
(R)-3-Amino-2-methylpropanoate:pyruvate aminotransferase

Catalysed by SCLY, AGXT2mitochondrial matrix

L-citrullineReach from here →

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

Catalysed by SCLY, SLC7A6extracellular space, cytosolOne of 4 routes

L-valineReach from here →

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

Catalysed by SCLY, SLC7A5extracellular space, cytosolOne of 9 routes

oxaloacetateReach from here →

A + NADH + H(+) = AH2 + NAD(+)
(R)-malate + A = oxaloacetate + AH2

Catalysed by AIFM1, PYROXD1, D2HGDH

L-arginineReach from here →

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

Catalysed by SCLY, SLC7A6extracellular space, cytosolOne of 8 routes

protein polypeptide chainReach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
PROTEIN_BS

Catalysed by SCLYcytosolOne of 2 routes

CHEBI:16633Reach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-selenocysteine selenide-lyase (L-alanine-forming)

Catalysed by SCLYcytosol

Met-tRNA(Met)Reach from here →

N(6)-dimethylallyladenosine(37) in tRNA + (sulfur carrier)-SH + AH2 + 2 S-adenosyl-L-methionine = 2-methylsulfanyl-N(6)-dimethylallyladenosine(37) in tRNA + (sulfur carrier)-H + 5'-deoxyadenosine + L-methionine + A + S-adenosyl-L-homocysteine + 2 H(+)
L-Methionine:tRNAMet ligase (AMP-forming)

Catalysed by CDK5RAP1, MARS1cytosol

(S)-lactateReach from here →

(5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 O2 = prostaglandin H2 + A + H2O
prostaglandin H2(out) + 2 (S)-lactate(in) = prostaglandin H2(in) + 2 (S)-lactate(out)

Catalysed by PTGS1, PTGS2, SLCO2A1inner side of the membrane, outer side of the membraneOne of 2 routes

4-methylsulfanyl-2-oxobutanoateReach from here →

N(6)-dimethylallyladenosine(37) in tRNA + (sulfur carrier)-SH + AH2 + 2 S-adenosyl-L-methionine = 2-methylsulfanyl-N(6)-dimethylallyladenosine(37) in tRNA + (sulfur carrier)-H + 5'-deoxyadenosine + L-methionine + A + S-adenosyl-L-homocysteine + 2 H(+)
glyoxylate + L-methionine = 4-methylsulfanyl-2-oxobutanoate + glycine

Catalysed by CDK5RAP1, AADAT

formaldehydeReach from here →

A + NADH + H(+) = AH2 + NAD(+)
N(6),N(6)-dimethyl-L-lysyl(4)-[histone H3] + 2 A + 2 H2O = L-lysyl(4)-[histone H3] + 2 formaldehyde + 2 AH2

Catalysed by AIFM1, PYROXD1, KDM1A, KDM1BOne of 3 routes

CHEBI:16856Reach from here →

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

Catalysed by DIO1, DIO2, SLCO1A2, SLCO1B3extracellular space, cytosolOne of 5 routes

CHEBI:16857Reach from here →

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

Catalysed by SCLY, SLC7A5extracellular space, cytosolOne of 7 routes

sn-glycerol 3-phosphocholineReach from here →

2-(5Z,8Z,11Z,14Z)-eicosatetraenoyl-sn-glycero-3-phosphocholine + AH2 + O2 = 2-[(11R)-hydroxy-(5Z,8Z,12E,14Z)-eicosatetraenoyl]-sn-glycero-3-phosphocholine + A + H2O
2-[(11R)-hydroxy-(5Z,8Z,12E,14Z)-eicosatetraenoyl]-sn-glycero-3-phosphocholine + H2O = (11R)-hydroxy-(5Z,8Z,12E,14Z)-eicosatetraenoate + sn-glycerol 3-phosphocholine + H(+)

Catalysed by PTGS2, PLA2G4AOne of 3 routes

L-isoleucineReach from here →

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

Catalysed by SCLY, SLC7A5extracellular space, cytosolOne of 6 routes

CHEBI:17203Reach from here →

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

Catalysed by SCLY, SLC7A5extracellular space, cytosolOne of 6 routes

all-trans-retinolReach from here →

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

Catalysed by AIFM1, PYROXD1, RETSATOne of 2 routes

L-cysteineReach from here →

A + NADH + H(+) = AH2 + NAD(+)
Mo-molybdopterin + L-cysteine + AH2 = thio-Mo-molybdopterin + L-alanine + A + H2O

Catalysed by AIFM1, PYROXD1, MOCOSOne of 19 routes

diiodineReach from here →

3,3',5'-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
iodide:hydrogen-peroxide oxidoreductase

Catalysed by DIO1, DIO3, TPOcytosolOne of 2 routes

nitrateReach from here →

2 nitrite + AH2 + 2 H(+) = 2 nitric oxide + A + 2 H2O
Fe(II)-heme b-[protein] + nitric oxide + O2 = Fe(III)-heme b-[protein] + nitrate

Catalysed by SUOX, CYGB

3,3',5-triiodo-L-thyronine sulfateReach from here →

3,3',5-triiodo-L-thyronine + iodide + A + H(+) = L-thyroxine + AH2
aryl sulfotransferase (PAPS)

Catalysed by DIO1, DIO2, SULT1A3, SULT1A4 and 2 morecytosolOne of 2 routes

Ala-tRNA(Ala)Reach from here →

L-selenocysteine + AH2 = hydrogenselenide + L-alanine + A + H(+)
L-Alanine:tRNA(Ala) ligase (AMP-forming)

Catalysed by SCLY, AARS1cytosol