L-homocysteine
362,296 routes · scope human · up to 3 steps · built 5 October 2026 · Reactions · API
512 compounds within 3 steps: 8 in 1, 58 in 2, 446 in 3
Three steps
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- long-chain-fatty-acid-CoA ligase (lauric acid)
Catalysed by CBS, NAGS, SLC27A2, ACSL4 and 6 moremitochondrial matrix, cytosolOne of 9 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- Production of Glutaryl Carnitine
Catalysed by CBS, NAGS, CPT1A, CPT1C and 1 moremitochondrial matrix, cytosolOne of 2 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- long-chain-fatty-acid-CoA ligase (eicosanoate)
Catalysed by CBS, NAGS, SLC27A2, ACSL4 and 6 moremitochondrial matrix, cytosolOne of 12 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- Itaconate:CoA ligase (GDP-forming)
Catalysed by CBS, NAGS, SUCLG1, SUCLG2 and 1 moremitochondrial matrixOne of 2 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- long-chain-fatty-acid-CoA ligase ((6Z,9Z)-octadecadienoic acid)
Catalysed by CBS, NAGS, SLC27A2, ACSL4 and 6 moremitochondrial matrix, cytosolOne of 13 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- long-chain-fatty-acid-CoA ligase (myristic acid)
Catalysed by CBS, NAGS, SLC27A2, ACSL4 and 6 moremitochondrial matrix, cytosolOne of 11 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- Octanoyl-CoA:L-carnitine O-octanoyltransferase
Catalysed by CBS, NAGS, CROTmitochondrial matrixOne of 20 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- phytanate-CoA ligase
Catalysed by CBS, NAGSmitochondrial matrix, cytosolOne of 5 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- long-chain-fatty-acid-CoA ligase (stearate)
Catalysed by CBS, NAGS, SLC27A2, ACSL4 and 5 moremitochondrial matrix, cytosolOne of 15 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- N(6)-L-threonylcarbamoyladenosine(37) in tRNA + (sulfur carrier)-SH + AH2 + 2 S-adenosyl-L-methionine = 2-methylsulfanyl-N(6)-L-threonylcarbamoyladenosine(37) in tRNA + (sulfur carrier)-H + 5'-deoxyadenosine + L-methionine + A + S-adenosyl-L-homocysteine + 2 H(+)
- (5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 O2 = prostaglandin H2 + A + H2O
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- N(6)-L-threonylcarbamoyladenosine(37) in tRNA + (sulfur carrier)-SH + AH2 + 2 S-adenosyl-L-methionine = 2-methylsulfanyl-N(6)-L-threonylcarbamoyladenosine(37) in tRNA + (sulfur carrier)-H + 5'-deoxyadenosine + L-methionine + A + S-adenosyl-L-homocysteine + 2 H(+)
- (15S)-hydroperoxy-(5Z,8Z,11Z,13E)-eicosatetraenoate + AH2 = (15S)-hydroxy-(5Z,8Z,11Z,13E)-eicosatetraenoate + A + H2O
Catalysed by MTR, CDKAL1, TBXAS1, PTGS2 and 1 moreOne of 2 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of alanine and methionine (cytosol to extracellular)
- D-alanine(out) + L-alanine(in) = D-alanine(in) + L-alanine(out)
Catalysed by MTR, SLC7A5, SLC7A10extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 2 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of arginine and methionine (cytosol to extracellular)
- 2-(Nomega-L-arginino)succinate arginine-lyase (fumarate-forming)
Catalysed by MTR, SLC7A6, ASLextracellular space, cytosolOne of 6 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of methionine and phenylalanine (cytosol to extracellular)
- L-dopa(out) + L-phenylalanine(in) = L-dopa(in) + L-phenylalanine(out)
Catalysed by MTR, SLC7A5, SLC7A8extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 2 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- L-aspartate(in) + L-methionine(out) = L-aspartate(out) + L-methionine(in)
- IMP:L-aspartate ligase (GDP-forming)
Catalysed by MTR, SLC7A13, ADSS2, ADSS1inner side of the membrane, outer side of the membrane, cytosolOne of 2 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of methionine and phenylalanine (cytosol to extracellular)
- L-histidine(in) + L-phenylalanine(out) = L-histidine(out) + L-phenylalanine(in)
Catalysed by MTR, SLC7A5, SLC7A8extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 7 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of methionine and ornithine (cytosol to extracellular)
- D-ornithine(in) + L-ornithine(out) = D-ornithine(out) + L-ornithine(in)
Catalysed by MTR, SLC7A6, SLC25A2extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 2 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- acyl-CoA:sphingosine N-acyltransferase
Catalysed by CBS, NAGS, ASAH1, ACER2 and 2 moremitochondrial matrix, Golgi apparatusOne of 2 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of alanine and methionine (cytosol to extracellular)
- D-threonine(out) + L-alanine(in) = D-threonine(in) + L-alanine(out)
Catalysed by MTR, SLC7A5, SLC7A10extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 2 routes
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- diamine N-acetyltransferase (N1-acetylspermidine)
Catalysed by CBS, NAGS, SAT1, SAT2mitochondrial matrix, cytosolOne of 3 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of lysine and methionine (cytosol to extracellular)
- N6-(L-1,3-Dicarboxypropyl)-L-lysine:NADP+ oxidoreductase (L-lysine-forming)
Catalysed by MTR, SLC7A6, AASSextracellular space, cytosol, mitochondrial matrix
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of alanine and methionine (cytosol to extracellular)
- L-kynurenine + H2O = anthranilate + L-alanine + H(+)
Catalysed by MTR, SLC7A5, KYNUextracellular space, cytosolOne of 5 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of alanine and methionine (cytosol to extracellular)
- beta-alanine(out) + L-alanine(in) = beta-alanine(in) + L-alanine(out)
Catalysed by MTR, SLC7A5, SLC7A10extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 6 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- L-aspartate(in) + L-methionine(out) = L-aspartate(out) + L-methionine(in)
- N(4)-(beta-N-acetyl-D-glucosaminyl)-L-asparagine + H2O = N-acetyl-beta-D-glucosaminylamine + L-aspartate + H(+)
Catalysed by MTR, SLC7A13, AGAinner side of the membrane, outer side of the membrane
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of lysine and methionine (cytosol to extracellular)
- L-lysine:oxygen 2-oxidoreductase (deaminating)
Catalysed by MTR, SLC7A6extracellular space, cytosol, peroxisome
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of glutamine and methionine (cytosol to extracellular)
- HCO3-:L-glutamine amido-ligase (ADP-forming, carbamate-phosphorylating)
Catalysed by MTR, SLC7A5, CADextracellular space, cytosolOne of 4 routes
- L-homocysteine + H2O = 2-oxobutanoate + hydrogen sulfide + NH4(+) + H(+)
- hydrogen sulfide + 2 O2 = sulfate + H(+)
- ATP:sulfate adenylyltransferase
Catalysed by CTH, SOD1, PAPSS1, PAPSS2cytosolOne of 4 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + glycine + H2O = (6S)-5,6,7,8-tetrahydrofolate + L-serine
- N(omega),N(omega)-dimethyl-L-arginine + glyoxylate = 5-(3,3-dimethylguanidino)-2-oxopentanoate + glycine
- L-homocysteine + L-serine = L,L-cystathionine + H2O
- N-acetylglutamate synthase (N-acetyl-L-cystathionine)
- acyl-CoA:sphingosine N-acyltransferase
Catalysed by CBS, NAGS, ASAH1, ACER2 and 2 moremitochondrial matrix, Golgi apparatusOne of 2 routes
- (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
- transport of alanine and methionine (cytosol to extracellular)
- trans-4-hydroxy-L-proline(out) + L-alanine(in) + Na(+)(out) = trans-4-hydroxy-L-proline(in) + L-alanine(out) + Na(+)(in)
Catalysed by MTR, SLC7A5, SLC1A4extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 5 routes