(6S)-5-methyl-5,6,7,8-tetrahydrofolate

Three steps

• dodecanoyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. long-chain-fatty-acid-CoA ligase (lauric acid)

  Catalysed by MTR, NAGS, SLC27A2, ACSL4 and 6 moremitochondrial matrix, cytosolOne of 9 routes

• glutaryl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. Production of Glutaryl Carnitine

  Catalysed by MTR, NAGS, CPT1A, CPT1C and 1 moremitochondrial matrix, cytosolOne of 2 routes

• eicosanoyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. long-chain-fatty-acid-CoA ligase (eicosanoate)

  Catalysed by MTR, NAGS, SLC27A2, ACSL4 and 6 moremitochondrial matrix, cytosolOne of 12 routes

• itaconyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. Itaconate:CoA ligase (GDP-forming)

  Catalysed by MTR, NAGS, SUCLG1, SUCLG2 and 1 moremitochondrial matrixOne of 2 routes

• (9Z,12Z)-octadecadienoyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. long-chain-fatty-acid-CoA ligase ((6Z,9Z)-octadecadienoic acid)

  Catalysed by MTR, NAGS, SLC27A2, ACSL4 and 6 moremitochondrial matrix, cytosolOne of 13 routes

• tetradecanoyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. long-chain-fatty-acid-CoA ligase (myristic acid)

  Catalysed by MTR, NAGS, SLC27A2, ACSL4 and 6 moremitochondrial matrix, cytosolOne of 11 routes

• octanoyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. Octanoyl-CoA:L-carnitine O-octanoyltransferase

  Catalysed by MTR, NAGS, CROTmitochondrial matrixOne of 20 routes

• phytanoyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. phytanate-CoA ligase

  Catalysed by MTR, NAGSmitochondrial matrix, cytosolOne of 5 routes

• octadecanoyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. long-chain-fatty-acid-CoA ligase (stearate)

  Catalysed by MTR, NAGS, SLC27A2, ACSL4 and 5 moremitochondrial matrix, cytosolOne of 15 routes

• prostaglandin H2Reach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. 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(+)
  3. (5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 O2 = prostaglandin H2 + A + H2O

  Catalysed by MTR, CDKAL1, PTGS1, PTGS2One of 2 routes

• (15S)-hydroxy-(5Z,8Z,11Z,13E)-eicosatetraenoateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. 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(+)
  3. (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 more

• D-alanineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of alanine and methionine (cytosol to extracellular)
  3. 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

• sarcosineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + glycine + H2O = (6S)-5,6,7,8-tetrahydrofolate + L-serine
  3. sarcosine + O2 + H2O = formaldehyde + glycine + H2O2

  Catalysed by MTR, SHMT1, SHMT2, PIPOXOne of 2 routes

• (6R)-5,10-methenyltetrahydrofolateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. 5-formimidoyltetrahydrofolate + L-glutamate = N-formimidoyl-L-glutamate + (6S)-5,6,7,8-tetrahydrofolate
  3. 5-Formiminotetrahydrofolate ammonia-lyase (cyclizing)

  Catalysed by MTR, FTCDcytosolOne of 5 routes

• 2-(N(omega)-L-arginino)succinateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of arginine and methionine (cytosol to extracellular)
  3. 2-(Nomega-L-arginino)succinate arginine-lyase (fumarate-forming)

  Catalysed by MTR, SLC7A6, ASLextracellular space, cytosolOne of 6 routes

• 4-guanidinobutanoateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of arginine and methionine (cytosol to extracellular)
  3. 4-aminobutanoate + L-arginine = 4-guanidinobutanoate + L-ornithine

  Catalysed by MTR, SLC7A6, GATMextracellular space, cytosol

• L-dopaReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of methionine and phenylalanine (cytosol to extracellular)
  3. 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

• N(6)-(1,2-dicarboxyethyl)-AMPReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. L-aspartate(in) + L-methionine(out) = L-aspartate(out) + L-methionine(in)
  3. 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

• 3-guanidinopropanoateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of arginine and methionine (cytosol to extracellular)
  3. beta-alanine + L-arginine = 3-guanidinopropanoate + L-ornithine

  Catalysed by MTR, SLC7A6, GATMextracellular space, cytosol

• L-histidineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of methionine and phenylalanine (cytosol to extracellular)
  3. 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

• D-ornithineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of methionine and ornithine (cytosol to extracellular)
  3. 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

• an N-acylglycineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + glycine + H2O = (6S)-5,6,7,8-tetrahydrofolate + L-serine
  3. an acyl-CoA + glycine = an N-acylglycine + CoA + H(+)

  Catalysed by MTR, SHMT1, SHMT2, GLYATL3 and 2 more

• 2-oxo-3-sulfanylpropanoateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of cysteine and methionine (cytosol to extracellular)
  3. L-Cysteine:2-oxoglutarate aminotransferase

  Catalysed by MTR, SLC7A5, GOT2, GOT1extracellular space, cytosolOne of 3 routes

• guanidinoacetateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + glycine + H2O = (6S)-5,6,7,8-tetrahydrofolate + L-serine
  3. L-Arginine:glycine amidinotransferase

  Catalysed by MTR, SHMT1, SHMT2, GATMcytosolOne of 5 routes

• sphing-4-enineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. acyl-CoA:sphingosine N-acyltransferase

  Catalysed by MTR, NAGS, ASAH1, ACER2 and 2 moremitochondrial matrix, Golgi apparatusOne of 2 routes

• D-threonineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of alanine and methionine (cytosol to extracellular)
  3. 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

• spermidineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. diamine N-acetyltransferase (N1-acetylspermidine)

  Catalysed by MTR, NAGS, SAT1, SAT2mitochondrial matrix, cytosolOne of 3 routes

• L-dopaquinoneReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of methionine and tyrosine (cytosol to extracellular)
  3. L-Tyrosine,L-dopa:oxygen oxidoreductase

  Catalysed by MTR, SLC7A5, TYRextracellular space, cytosol

• glutathioneReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + glycine + H2O = (6S)-5,6,7,8-tetrahydrofolate + L-serine
  3. gamma-L-glutamyl-L-cysteine + glycine + ATP = glutathione + ADP + phosphate + H(+)

  Catalysed by MTR, SHMT1, SHMT2, GSS

• L-threonineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of alanine and methionine (cytosol to extracellular)
  3. L-threonine(out) + L-alanine(in) = L-threonine(in) + L-alanine(out)

  Catalysed by MTR, SLC7A5, SLC7A10extracellular space, cytosol, inner side of the membrane, outer side of the membraneOne of 8 routes

• L-saccharopineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of lysine and methionine (cytosol to extracellular)
  3. N6-(L-1,3-Dicarboxypropyl)-L-lysine:NADP+ oxidoreductase (L-lysine-forming)

  Catalysed by MTR, SLC7A6, AASSextracellular space, cytosol, mitochondrial matrix

• L-kynurenineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of alanine and methionine (cytosol to extracellular)
  3. L-kynurenine + H2O = anthranilate + L-alanine + H(+)

  Catalysed by MTR, SLC7A5, KYNUextracellular space, cytosolOne of 5 routes

• beta-alanineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of alanine and methionine (cytosol to extracellular)
  3. 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

• leukotriene C4Reach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + glycine + H2O = (6S)-5,6,7,8-tetrahydrofolate + L-serine
  3. leukotriene C4 hydrolysis

  Catalysed by MTR, SHMT1, SHMT2cytosol

• IMPReach from here →
  1. 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide(in) + (6S)-5-methyl-5,6,7,8-tetrahydrofolate(out) = 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide(out) + (6S)-5-methyl-5,6,7,8-tetrahydrofolate(in)
  2. (6R)-10-formyltetrahydrofolate + 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide = 5-formamido-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide + (6S)-5,6,7,8-tetrahydrofolate
  3. IMP + H2O = 5-formamido-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide

  Catalysed by SLC19A1, ATICinner side of the membrane, outer side of the membrane

• taurocyamineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of arginine and methionine (cytosol to extracellular)
  3. taurine + L-arginine = taurocyamine + L-ornithine

  Catalysed by MTR, SLC7A6, GATMextracellular space, cytosol

• L-glutamate 5-semialdehydeReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of methionine and ornithine (cytosol to extracellular)
  3. L-ornithine + 2-oxoglutarate = L-glutamate 5-semialdehyde + L-glutamate

  Catalysed by MTR, SLC7A6, OATextracellular space, cytosol

• N(4)-(beta-N-acetyl-D-glucosaminyl)-L-asparagineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. L-aspartate(in) + L-methionine(out) = L-aspartate(out) + L-methionine(in)
  3. 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

• 3-hydroxy-L-kynurenineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of alanine and methionine (cytosol to extracellular)
  3. 3-hydroxy-L-kynurenine + H2O = 3-hydroxyanthranilate + L-alanine + H(+)

  Catalysed by MTR, SLC7A5, KYNUextracellular space, cytosol

• L,L-cystathionineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. N-acetylglutamate synthase (N-acetyl-L-cystathionine)

  Catalysed by MTR, NAGSmitochondrial matrixOne of 2 routes

• gamma-L-glutamyl-L-cysteineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of cysteine and methionine (cytosol to extracellular)
  3. L-glutamate:L-cysteine gamma-ligase (ADP-forming)

  Catalysed by MTR, SLC7A5, GCLC, GCLMextracellular space, cytosolOne of 2 routes

• 6-amino-2-oxohexanoateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of lysine and methionine (cytosol to extracellular)
  3. L-lysine:oxygen 2-oxidoreductase (deaminating)

  Catalysed by MTR, SLC7A6extracellular space, cytosol, peroxisome

• carbamoyl phosphateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of glutamine and methionine (cytosol to extracellular)
  3. HCO3-:L-glutamine amido-ligase (ADP-forming, carbamate-phosphorylating)

  Catalysed by MTR, SLC7A5, CADextracellular space, cytosolOne of 4 routes

• N,N-dimethylglycineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. S-methyl-L-methionine + L-homocysteine = 2 L-methionine + H(+)
  3. L-homocysteine + glycine betaine = N,N-dimethylglycine + L-methionine

  Catalysed by MTR, BHMT2, BHMT

• L-tyrosineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + glycine + H2O = (6S)-5,6,7,8-tetrahydrofolate + L-serine
  3. L-tyrosine + glyoxylate = 3-(4-hydroxyphenyl)pyruvate + glycine

  Catalysed by MTR, SHMT1, SHMT2, AADATOne of 4 routes

• N(omega),N(omega)-dimethyl-L-arginineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + glycine + H2O = (6S)-5,6,7,8-tetrahydrofolate + L-serine
  3. N(omega),N(omega)-dimethyl-L-arginine + glyoxylate = 5-(3,3-dimethylguanidino)-2-oxopentanoate + glycine

  Catalysed by MTR, SHMT1, SHMT2, AGXT2One of 7 routes

• an acyl-CoAReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. N-acetylglutamate synthase (N-acetylmethionine)
  3. acyl-CoA:sphingosine N-acyltransferase

  Catalysed by MTR, NAGS, ASAH1, ACER2 and 2 moremitochondrial matrix, Golgi apparatusOne of 2 routes

• trans-4-hydroxy-L-prolineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of alanine and methionine (cytosol to extracellular)
  3. 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 2 routes

• histamineReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. transport of histidine and methionine (cytosol to extracellular)
  3. L-histidine carboxy-lyase (histamine-forming)

  Catalysed by MTR, SLC7A6, HDCextracellular space, cytosol

• kynurenateReach from here →
  1. (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine
  2. glyoxylate + L-methionine = 4-methylsulfanyl-2-oxobutanoate + glycine
  3. 4-methylsulfanyl-2-oxobutanoate + L-kynurenine = kynurenate + L-methionine + H2O

  Catalysed by MTR, AADAT