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Reach

testosterone

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

198 compounds within 3 steps: 16 in 1, 37 in 2, 145 in 3

Does it reach a compound?

Two steps

17beta-estradiol 17-O-(beta-D-glucuronate)Reach from here →
1. cytochrome P450 (testosterone)
2. 17beta-estradiol + UDP-alpha-D-glucuronate = 17beta-estradiol 17-O-(beta-D-glucuronate) + UDP + H(+)
Catalysed by CYP19A1, UGT2B17, UGT2A1, UGT2B7 and 2 moreendoplasmic reticulum
6beta-hydroxyandrost-4-ene-3,17-dioneReach from here →
1. testosterone + NAD(+) = androst-4-ene-3,17-dione + NADH + H(+)
2. androst-4-ene-3,17-dione + reduced [NADPH--hemoprotein reductase] + O2 = 6beta-hydroxyandrost-4-ene-3,17-dione + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
Catalysed by HSD17B6, AKR1C4, HSD17B2, AKR1C3 and 4 more
16beta,17beta-estriolReach from here →
1. cytochrome P450 (testosterone)
2. 17beta-estradiol + reduced [NADPH--hemoprotein reductase] + O2 = 16beta,17beta-estriol + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
Catalysed by CYP19A1, CYP3A4endoplasmic reticulum

Three steps

(S)-3-hydroxybutanoateReach from here →
Catalysed by CYP19A1, SLC16A4, SLC16A5, ADHFE1endoplasmic reticulum, extracellular space, cytosol
(S)-carnitineReach from here →

Page 2 of 4

Catalysed by CYP19A1, SLC26A4, SLC6A14

endoplasmic reticulum, extracellular space, cytosol

2-hydroxyestroneReach from here →

cytochrome P450 (testosterone)
Estradiol-17beta:NADP+ 17-oxidoreductase
cytochrome P450 (estrone)

Catalysed by CYP19A1, HSD17B6, HSD17B1, HSD17B2 and 5 moreendoplasmic reticulum, cytosolOne of 4 routes

prostaglandin E3Reach from here →

cytochrome P450 (testosterone)
transport of formate and L-lactate (cytosol to extracellular)
Transport of Prostaglandin E3, Lactate Antiport

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A3 and 3 moreendoplasmic reticulum, extracellular space, cytosolOne of 2 routes

prostaglandin A2Reach from here →

cytochrome P450 (testosterone)
transport of formate and L-lactate (cytosol to extracellular)
Transport of Prostaglandin A2, Lactate Antiport

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A3 and 3 moreendoplasmic reticulum, extracellular space, cytosolOne of 2 routes

prostaglandin J2Reach from here →

cytochrome P450 (testosterone)
transport of formate and L-lactate (cytosol to extracellular)
Transport of Prostaglandin J2, Lactate Antiport

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A3 and 3 moreendoplasmic reticulum, extracellular space, cytosolOne of 2 routes

15-oxoprostaglandin F2alphaReach from here →

cytochrome P450 (testosterone)
transport of formate and L-lactate (cytosol to extracellular)
Transport of 15-Keto-Prostaglandin F2A, Lactate Antiport

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A3 and 3 moreendoplasmic reticulum, extracellular space, cytosolOne of 2 routes

all-trans-4-hydroxyretinoateReach from here →

cytochrome P450 (testosterone)
transport of formate and retinoate (cytosol to extracellular)
cytochrome P450 (retinoate)

Catalysed by CYP19A1, SLC16A4, SLC16A5, CYP26A1endoplasmic reticulum, extracellular space, cytosolOne of 3 routes

N-acetylcadaverineReach from here →

cytochrome P450 (testosterone)
transport of acetate and formate (cytosol to extracellular)
N-acetylcadaverine + H2O = cadaverine + acetate

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A1 and 1 moreendoplasmic reticulum, extracellular space, cytosol

estrone 3-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
Estradiol-17beta:NADP+ 17-oxidoreductase
UDPglucuronate beta-D-glucuronosyltransferase(acceptor-unspecific)

Catalysed by CYP19A1, HSD17B6, HSD17B1, HSD17B2 and 7 moreendoplasmic reticulum, cytosolOne of 2 routes

16alpha,17beta-estriol 3-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
ESTRr
16alpha,17beta-estriol + UDP-alpha-D-glucuronate = 16alpha,17beta-estriol 3-O-(beta-D-glucuronate) + UDP + H(+)

Catalysed by CYP19A1, UGT1A10endoplasmic reticulum

16alpha,17beta-estriol 16-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
ESTRr
UDPglucuronate beta-D-glucuronosyltransferase(acceptor-unspecific)

Catalysed by CYP19A1, UGT2B4, UGT1A1, UGT2B28 and 2 moreendoplasmic reticulumOne of 2 routes

16beta,17beta-estriol 3-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
17beta-estradiol + reduced [NADPH--hemoprotein reductase] + O2 = 16beta,17beta-estriol + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
16beta,17beta-estriol + UDP-alpha-D-glucuronate = 16beta,17beta-estriol 3-O-(beta-D-glucuronate) + UDP + H(+)

Catalysed by CYP19A1, CYP3A4, UGT1A10endoplasmic reticulum

16beta,17beta-estriol 16-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
17beta-estradiol + reduced [NADPH--hemoprotein reductase] + O2 = 16beta,17beta-estriol + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
16beta,17beta-estriol + UDP-alpha-D-glucuronate = 16beta,17beta-estriol 16-O-(beta-D-glucuronate) + UDP + H(+)

Catalysed by CYP19A1, CYP3A4, UGT2A1, UGT2B7 and 1 moreendoplasmic reticulum

5alpha-dihydrotestosterone 17-O-[beta-D-glucuronosyl-(1->2)-glucuronate]Reach from here →

dihydrotestosterone:NADP+ delta4-oxidoreductase
glucuronosyltransferase (5-alpha-dihydrotestosterone)
5alpha-dihydrotestosterone 17-O-(beta-D-glucuronate) + UDP-alpha-D-glucuronate = 5alpha-dihydrotestosterone 17-O-[beta-D-glucuronosyl-(1->2)-glucuronate] + UDP + H(+)

Catalysed by SRD5A1, SRD5A2, SRD5A3, UGT2B4 and 4 morecytosol, endoplasmic reticulum

2-hydroxy-17beta-estradiol 3-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
unspecific monooxygenase (estradiol-17beta)
2-hydroxy-17beta-estradiol + UDP-alpha-D-glucuronate = 2-hydroxy-17beta-estradiol 3-O-(beta-D-glucuronate) + UDP + H(+)

Catalysed by CYP19A1, CYP1A1, CYP1A2, CYP2E1 and 25 moreendoplasmic reticulum, cytosol

17beta-estradiol 2-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
unspecific monooxygenase (estradiol-17beta)
2-hydroxy-17beta-estradiol + UDP-alpha-D-glucuronate = 17beta-estradiol 2-O-(beta-D-glucuronate) + UDP + H(+)

Catalysed by CYP19A1, CYP1A1, CYP1A2, CYP2E1 and 22 moreendoplasmic reticulum, cytosol

4-hydroxy-17beta-estradiol 3-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
cytochrome P450 (estradiol-17beta)
4-hydroxy-17beta-estradiol + UDP-alpha-D-glucuronate = 4-hydroxy-17beta-estradiol 3-O-(beta-D-glucuronate) + UDP + H(+)

Catalysed by CYP19A1, CYP3A4, UGT1A8endoplasmic reticulum, cytosol

17beta-estradiol 4-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
cytochrome P450 (estradiol-17beta)
4-hydroxy-17beta-estradiol + UDP-alpha-D-glucuronate = 17beta-estradiol 4-O-(beta-D-glucuronate) + UDP + H(+)

Catalysed by CYP19A1, CYP3A4, UGT1A9, UGT2B7 and 1 moreendoplasmic reticulum, cytosol

4-methoxy-17beta-estradiolReach from here →

cytochrome P450 (testosterone)
cytochrome P450 (estradiol-17beta)
4-hydroxy-17beta-estradiol + S-adenosyl-L-methionine = 4-methoxy-17beta-estradiol + S-adenosyl-L-homocysteine + H(+)

Catalysed by CYP19A1, CYP3A4, COMTendoplasmic reticulum, cytosol

all-trans-retinoyl-1-O-(beta-D-glucuronate)Reach from here →

cytochrome P450 (testosterone)
transport of formate and retinoate (cytosol to extracellular)
glucuronosyltransferase (retinoate)

Catalysed by CYP19A1, SLC16A4, SLC16A5, UGT1A1 and 2 moreendoplasmic reticulum, extracellular space, cytosol

all-trans-18-hydroxyretinoateReach from here →

cytochrome P450 (testosterone)
transport of formate and retinoate (cytosol to extracellular)
unspecific monooxygenase (retinoate)

Catalysed by CYP19A1, SLC16A4, SLC16A5, CYP1A1 and 24 moreendoplasmic reticulum, extracellular space, cytosolOne of 2 routes

a phenyl acetateReach from here →

cytochrome P450 (testosterone)
transport of acetate and formate (cytosol to extracellular)
a phenyl acetate + H2O = a phenol + acetate + H(+)

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A1 and 3 moreendoplasmic reticulum, extracellular space, cytosol

3-(methylthio)propionic acidReach from here →

testosterone + 3 reduced [NADPH--hemoprotein reductase] + 3 O2 = 17beta-estradiol + formate + 3 oxidized [NADPH--hemoprotein reductase] + 4 H2O + 4 H(+)
1,2-dihydroxy-5-(methylsulfanyl)pent-1-en-3-one + O2 = 3-(methylsulfanyl)propanoate + CO + formate + 2 H(+)
acireductone dioxygenase

Catalysed by CYP19A1, ADI1cytosol

N(2)-formyl-N(1)-(5-phospho-beta-D-ribosyl)glycinamideReach from here →

testosterone + 3 reduced [NADPH--hemoprotein reductase] + 3 O2 = 17beta-estradiol + formate + 3 oxidized [NADPH--hemoprotein reductase] + 4 H2O + 4 H(+)
(6S)-5,6,7,8-tetrahydrofolate + formate + ATP = (6R)-10-formyltetrahydrofolate + ADP + phosphate
N(1)-(5-phospho-beta-D-ribosyl)glycinamide + (6R)-10-formyltetrahydrofolate = N(2)-formyl-N(1)-(5-phospho-beta-D-ribosyl)glycinamide + (6S)-5,6,7,8-tetrahydrofolate + H(+)

Catalysed by CYP19A1, MTHFD1, MTHFD1L, GART

acetaldehydeReach from here →

testosterone + NAD(+) = androst-4-ene-3,17-dione + NADH + H(+)
cytochrome P450 (17alpha-hydroxyprogesterone)
cytochrome P450 (17alpha-hydroxyprogesterone)

Catalysed by HSD17B6, AKR1C4, HSD17B2, AKR1C3 and 3 moreendoplasmic reticulum

CHEBI:15345Reach from here →

cytochrome P450 (testosterone)
transport of acetoacetate and formate (cytosol to extracellular)
Acetoacetate:CoA ligase (AMP-forming)

Catalysed by CYP19A1, SLC16A4, SLC16A5, AACSendoplasmic reticulum, extracellular space, cytosolOne of 3 routes

acetoneReach from here →

cytochrome P450 (testosterone)
transport of acetoacetate and formate (cytosol to extracellular)
Acetoacetate carboxy-lyase (acetone-forming)

Catalysed by CYP19A1, SLC16A4, SLC16A5endoplasmic reticulum, extracellular space, cytosol, mitochondrial matrix

cholineReach from here →

cytochrome P450 (testosterone)
transport of chloride and formate (cytosol to extracellular)
transport of chloride and choline (cytosol to extracellular)

Catalysed by CYP19A1, SLC26A4, SLC5A7endoplasmic reticulum, extracellular space, cytosol

acetylpyruvateReach from here →

cytochrome P450 (testosterone)
transport of formate and pyruvate (cytosol to extracellular)
acetylpyruvate + H2O = acetate + pyruvate + H(+)

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A7 and 3 moreendoplasmic reticulum, extracellular space, cytosolOne of 2 routes

propionyl-CoAReach from here →

cytochrome P450 (testosterone)
transport of formate and propanoate (cytosol to extracellular)
Propanoate:CoA ligase (AMP-forming)

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A1 and 3 moreendoplasmic reticulum, extracellular space, cytosolOne of 3 routes

(S)-malateReach from here →

cytochrome P450 (testosterone)
transport of formate and pyruvate (cytosol to extracellular)
(S)-malate + NAD(+) = pyruvate + CO2 + NADH

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A7 and 3 moreendoplasmic reticulum, extracellular space, cytosolOne of 2 routes

L-leucineReach from here →

cytochrome P450 (testosterone)
transport of chloride and formate (cytosol to extracellular)
transport of chloride and leucine (cytosol to extracellular)

Catalysed by CYP19A1, SLC26A4, SLC6A14endoplasmic reticulum, extracellular space, cytosolOne of 2 routes

CHEBI:15971Reach from here →

cytochrome P450 (testosterone)
transport of chloride and formate (cytosol to extracellular)
transport of chloride and histidine (cytosol to extracellular)

Catalysed by CYP19A1, SLC26A4, SLC6A14endoplasmic reticulum, extracellular space, cytosol

methanethiolReach from here →

testosterone + 3 reduced [NADPH--hemoprotein reductase] + 3 O2 = 17beta-estradiol + formate + 3 oxidized [NADPH--hemoprotein reductase] + 4 H2O + 4 H(+)
formaldehyde + NAD(+) + H2O = formate + NADH + 2 H(+)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)

Catalysed by CYP19A1, ALDH9A1, SELENBP1

androsteroneReach from here →

dihydrotestosterone:NADP+ delta4-oxidoreductase
3beta-Hydroxysteroid:NADP+ oxidoreductase
5alpha-androstane-3alpha,17beta-diol + NAD(+) = androsterone + NADH + H(+)

Catalysed by SRD5A1, SRD5A2, SRD5A3, AKR1C4 and 3 morecytosolOne of 7 routes

sulfateReach from here →

dihydrotestosterone:NADP+ delta4-oxidoreductase
steroid sulfatase (5-alpha-dihydrotestosterone)
steroid sulfatase (5-alpha-dihydrotestosterone)

Catalysed by SRD5A1, SRD5A2, SRD5A3, STScytosolOne of 6 routes

2-methyl-3-oxopropanoic acidReach from here →

cytochrome P450 (testosterone)
transport of formate and pyruvate (cytosol to extracellular)
(R)-3-Amino-2-methylpropanoate:pyruvate aminotransferase

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A7 and 3 moreendoplasmic reticulum, extracellular space, cytosol, mitochondrial matrix

iodideReach from here →

cytochrome P450 (testosterone)
transport of chloride and formate (cytosol to extracellular)
transport of chloride and iodide (cytosol to extracellular)

Catalysed by CYP19A1, SLC26A4endoplasmic reticulum, extracellular space, cytosol

L-valineReach from here →

cytochrome P450 (testosterone)
transport of chloride and formate (cytosol to extracellular)
transport of chloride and valine (cytosol to extracellular)

Catalysed by CYP19A1, SLC26A4, SLC6A14endoplasmic reticulum, extracellular space, cytosolOne of 2 routes

(17R,20S)-17,20-dihydroxypregn-4-en-3-oneReach from here →

testosterone + NAD(+) = androst-4-ene-3,17-dione + NADH + H(+)
cytochrome P450 (17alpha-hydroxyprogesterone)
(17R,20S)-17,20-dihydroxypregn-4-en-3-one + NAD(+) = 17alpha-hydroxyprogesterone + NADH + H(+)

Catalysed by HSD17B6, AKR1C4, HSD17B2, AKR1C3 and 4 moreendoplasmic reticulumOne of 2 routes

oxaloacetateReach from here →

cytochrome P450 (testosterone)
transport of formate and pyruvate (cytosol to extracellular)
Pyruvate:carbon-dioxide ligase (ADP-forming)

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A7 and 3 moreendoplasmic reticulum, extracellular space, cytosol, mitochondrial matrixOne of 3 routes

L-arginineReach from here →

cytochrome P450 (testosterone)
transport of chloride and formate (cytosol to extracellular)
transport of arginine and chloride (cytosol to extracellular)

Catalysed by CYP19A1, SLC26A4, SLC6A14endoplasmic reticulum, extracellular space, cytosolOne of 2 routes

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

cytochrome P450 (testosterone)
transport of acetate and formate (cytosol to extracellular)
N2-Acetyl-L-ornithine amidohydrolase

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A1 and 1 moreendoplasmic reticulum, extracellular space, cytosol

(S)-lactateReach from here →

cytochrome P450 (testosterone)
transport of formate and pyruvate (cytosol to extracellular)
(S)-lactate + NAD(+) = pyruvate + NADH + H(+)

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A7 and 7 moreendoplasmic reticulum, extracellular space, cytosol

4-methylsulfanyl-2-oxobutanoateReach from here →

testosterone + 3 reduced [NADPH--hemoprotein reductase] + 3 O2 = 17beta-estradiol + formate + 3 oxidized [NADPH--hemoprotein reductase] + 4 H2O + 4 H(+)
1,2-dihydroxy-5-(methylsulfanyl)pent-1-en-3-one + O2 = 3-(methylsulfanyl)propanoate + CO + formate + 2 H(+)
1,2-dihydroxy-5-(methylsulfanyl)pent-1-en-3-one + O2 = 4-methylsulfanyl-2-oxobutanoate + formate + 2 H(+)

Catalysed by CYP19A1, ADI1

2-oxobutanoateReach from here →

cytochrome P450 (testosterone)
transport of 2-hydroxybutyrate and formate (cytosol to extracellular)
2-hydroxybutyrate:NAD+ oxidoreductase

Catalysed by CYP19A1, SLC16A4, SLC16A5, SLC16A7 and 5 moreendoplasmic reticulum, extracellular space, cytosolOne of 2 routes