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L-homocysteinyl-AMP

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

12 compounds within 3 steps: 1 in 1, 2 in 2, 9 in 3

Does it reach a compound?

One step

L-homocysteine thiolactoneReach from here →
1. L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
Catalysed by MARS1

Two steps

homocysteineReach from here →
1. L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
2. arylesterase (homocysteine-thiolactone)
Catalysed by MARS1, PON1, PON2, PON3cytosol
L-homocysteineReach from here →
1. L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
2. L-homocysteine thiolactone + H2O = L-homocysteine + H(+)
Catalysed by MARS1, BPHL

Three steps

2-oxobutanoateReach from here →
Catalysed by MARS1, BPHL, CTH
CHEBI:16856Reach from here →
Catalysed by MARS1, PON1

cytosol

CHEBI:17724Reach from here →

L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
arylesterase (homocysteine-thiolactone)
Trimethylaminoacetate:L-homosysteine S-methyltransferase

Catalysed by MARS1, PON1, PON2, PON3 and 2 morecytosol

5,6,7,8-tetrahydrofolic acidReach from here →

L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
arylesterase (homocysteine-thiolactone)
5-methyltetrahydrofolate:L-homocysteine S-methyltransferase

Catalysed by MARS1, PON1, PON2, PON3 and 1 morecytosol

hydrogen sulfideReach from here →

L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
L-homocysteine thiolactone + H2O = L-homocysteine + H(+)
L-homocysteine + H2O = 2-oxobutanoate + hydrogen sulfide + NH4(+) + H(+)

Catalysed by MARS1, BPHL, CTH

(6S)-5,6,7,8-tetrahydrofolateReach from here →

L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
L-homocysteine thiolactone + H2O = L-homocysteine + H(+)
(6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine

Catalysed by MARS1, BPHL, MTR

L-methionineReach from here →

L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
arylesterase (homocysteine-thiolactone)
5-methyltetrahydrofolate:L-homocysteine S-methyltransferase

Catalysed by MARS1, PON1, PON2, PON3 and 1 morecytosolOne of 5 routes

L,L-cystathionineReach from here →

L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
arylesterase (homocysteine-thiolactone)
L-serine hydro-lyase (adding homocysteine

Catalysed by MARS1, PON1, PON2, PON3 and 1 morecytosolOne of 2 routes

N,N-dimethylglycineReach from here →

L-homocysteinyl-AMP = L-homocysteine thiolactone + AMP + H(+)
L-homocysteine thiolactone + H2O = L-homocysteine + H(+)
L-homocysteine + glycine betaine = N,N-dimethylglycine + L-methionine

Catalysed by MARS1, BPHL, BHMT