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3-(methylthio)propionic acid

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

17 compounds within 3 steps: 1 in 1, 2 in 2, 14 in 3

Does it reach a compound?

One step

methanethiolReach from here →
1. leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
No catalyst recordedcytosol

Two steps

formaldehydeReach from here →
1. leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
2. methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
Catalysed by SELENBP1cytosol
hydrogen sulfideReach from here →
1. leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
2. methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
Catalysed by SELENBP1cytosol

Three steps

formateReach from here →
Catalysed by SELENBP1, ALDH9A1cytosol
sulfateReach from here →
Catalysed by SELENBP1, SOD1

cytosol

L-cysteineReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
L-serine hydro-lyase (adding hydrogen sulfide, L-cysteine-forming)

Catalysed by SELENBP1, CBScytosol

CHEBI:17724Reach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
dimethylglycine dehydrogenase (formaldehyde)

Catalysed by SELENBP1, PDPR, DMGDHcytosol

(6R)-5,10-methylenetetrahydrofolic acidReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
formaldehyde to 5,10-methylene-THF conversion

Catalysed by SELENBP1cytosol

a quinolReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
a quinone + hydrogen sulfide + glutathione + H(+) = S-sulfanylglutathione + a quinol

Catalysed by SELENBP1, SQORcytosol

a thiolReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
L-cysteinyl-[sulfatase] + 2 a thiol + O2 = an organic disulfide + 3-oxo-L-alanyl-[sulfatase] + hydrogen sulfide + H2O + H(+)

Catalysed by SELENBP1, SUMF1cytosol

thiosulfateReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
thiosulfate + 2 glutathione = glutathione disulfide + hydrogen sulfide + sulfite + 2 H(+)

Catalysed by SELENBP1, TSTD1cytosolOne of 2 routes

sarcosineReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
sarcosine + O2 + H2O = formaldehyde + glycine + H2O2

Catalysed by SELENBP1, PIPOXcytosol

2-oxo-3-sulfanylpropanoateReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
2-oxo-3-sulfanylpropanoate + [thioredoxin]-dithiol = [thioredoxin]-disulfide + hydrogen sulfide + pyruvate + H(+)

Catalysed by SELENBP1, MPSTcytosol

S-formylglutathioneReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
alcohol dehydrogenase (formaldehyde)

Catalysed by SELENBP1, ADH1C, ADH1A, ADH5 and 3 morecytosol

glutathioneReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
thiosulfate + 2 glutathione = glutathione disulfide + hydrogen sulfide + sulfite + 2 H(+)

Catalysed by SELENBP1, TSTD1cytosol

S-sulfanylglutathioneReach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
Sulfide:glutathione,quinone oxidoreductase

Catalysed by SELENBP1, SQORcytosol, mitochondrial matrixOne of 3 routes

ubiquinol-10Reach from here →

leukotriene-B4 20-monooxygenase (3-(methylthio)propionic acid)
methanethiol + O2 + H2O = hydrogen sulfide + formaldehyde + H2O2 + H(+)
ubiquinone-10 + hydrogen sulfide + sulfite + 2 H(+) = ubiquinol-10 + thiosulfate

Catalysed by SELENBP1, SQORcytosolOne of 2 routes