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Record Information
Creation Date2014-08-29 06:27:43 UTC
Update Date2018-03-21 17:46:17 UTC
Accession NumberT3D4328
Common NameL-Methionine
ClassSmall Molecule
DescriptionMethionine is an essential amino acid (there are 9 essential amino acids) required for normal growth and development of humans, other mammals, and avian species. In addition to being a substrate for protein synthesis, it is an intermediate in transmethylation reactions, serving as the major methyl group donor in vivo, including the methyl groups for DNA and RNA intermediates. Methionine is a methyl acceptor for 5-methyltetrahydrofolate-homocysteine methyltransferase (methionine synthase), the only reaction that allows for the recycling of this form of folate, and is also a methyl acceptor for the catabolism of betaine. Methionine is the metabolic precursor for cysteine. Only the sulfur atom from methionine is transferred to cysteine; the carbon skeleton of cysteine is donated by serine (PMID: 16702340). There is a general consensus concerning normal sulfur amino acid (SAA) requirements. WHO recommendations amount to 13 mg/kg per 24 h in healthy adults. This amount is roughly doubled in artificial nutrition regimens. In disease or after trauma, requirements may be altered for methionine, cysteine, and taurine. Although in specific cases of congenital enzyme deficiency, prematurity, or diminished liver function, hypermethioninemia or hyperhomocysteinemia may occur, SAA supplementation can be considered safe in amounts exceeding 2-3 times the minimum recommended daily intake. Apart from some very specific indications (e.g. acetaminophen poisoning) the usefulness of SAA supplementation is not yet established (PMID: 16702341). Methionine is known to exacerbate psychopathological symptoms in schizophrenic patients, but there is no evidence of similar effects in healthy subjects. The role of methionine as a precursor of homocysteine is the most notable cause for concern. Acute doses of methionine can lead to acute increases in plasma homocysteine, which can be used as an index of the susceptibility to cardiovascular disease. Sufficiently high doses of methionine can actually result in death. Longer-term studies in adults have indicated no adverse consequences of moderate fluctuations in dietary methionine intake, but intakes higher than 5 times the normal amount resulted in elevated homocysteine levels. These effects of methionine on homocysteine and vascular function are moderated by supplements of vitamins B-6, B-12, C, and folic acid (PMID: 16702346). When present in sufficiently high levels, methionine can act as an atherogen and a metabotoxin. An atherogen is a compound that when present at chronically high levels causes atherosclerosis and cardiovascular disease. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of methionine are associated with at least ten inborn errors of metabolism, including cystathionine beta-synthase deficiency, glycine N-methyltransferase deficiency, homocystinuria, tyrosinemia, galactosemia, homocystinuria-megaloblastic anemia due to defects in cobalamin metabolism, methionine adenosyltransferase deficiency, methylenetetrahydrofolate reductase deficiency, and S-adenosylhomocysteine (SAH) hydrolase deficiency. Chronically elevated levels of methionine in infants can lead to intellectual disability and other neurological problems, delays in motor skills, sluggishness, muscle weakness, and liver problems. Many individuals with these metabolic disorders tend to develop cardiovascular disease later in life. Studies on feeding rodents high levels of methionine have shown that methionine promotes atherosclerotic plaques independently of homocysteine levels (PMID: 26647293). A similar study in Finnish men showed the same effect (PMID: 16487911).
Compound Type
  • Amine
  • Amino Acid, Essential
  • Animal Toxin
  • Dietary Supplement
  • Drug
  • Ether
  • Food Toxin
  • Household Toxin
  • Metabolite
  • Micronutrient
  • Natural Compound
  • Nutraceutical
  • Organic Compound
  • Supplement
Chemical Structure
(2S)-2-amino-4-(methylsulfanyl)butanoic acid
(S)-2-amino-4-(methylthio)-Butanoic acid
(S)-2-Amino-4-(methylthio)butanoic acid
(S)-2-amino-4-(methylthio)butyric acid
2-Amino-4-(methylthio)butyric acid
2-Amino-4-methylthiobutanoic acid
A-Amino-g-methylmercaptobutyric acid
alpha-Amino-alpha-aminobutyric acid
alpha-Amino-gamma-methylmercaptobutyric acid
G-Methylthio-a-aminobutyric acid
gamma-Methylthio-alpha-aminobutyric acid
L(-)-Amino-alpha-amino-alpha-aminobutyric acid
L(-)-Amino-gamma-methylthiobutyric acid
L-2-Amino-4-(methylthio)butyric acid
L-2-Amino-4-methylthiobutyric acid
L-a-Amino-g-methylthiobutyric acid
L-alpha-Amino-gamma-methylmercaptobutyric acid
L-alpha-Amino-gamma-methylthiobutyric acid
L-gamma-Methylthio-alpha-aminobutyric acid
L-α-amino-γ-methylmercaptobutyric acid
Toxin WAR
Chemical FormulaC5H11NO2S
Average Molecular Mass149.211 g/mol
Monoisotopic Mass149.051 g/mol
CAS Registry Number63-68-3
IUPAC Name(2S)-2-amino-4-(methylsulfanyl)butanoic acid
Traditional NameL-methionine
InChI IdentifierInChI=1S/C5H11NO2S/c1-9-3-2-4(6)5(7)8/h4H,2-3,6H2,1H3,(H,7,8)/t4-/m0/s1
Chemical Taxonomy
Description belongs to the class of organic compounds known as methionine and derivatives. Methionine and derivatives are compounds containing methionine or a derivative thereof resulting from reaction of methionine at the amino group or the carboxy group, or from the replacement of any hydrogen of glycine by a heteroatom.
KingdomOrganic compounds
Super ClassOrganic acids and derivatives
ClassCarboxylic acids and derivatives
Sub ClassAmino acids, peptides, and analogues
Direct ParentMethionine and derivatives
Alternative Parents
  • Methionine or derivatives
  • Alpha-amino acid
  • L-alpha-amino acid
  • Thia fatty acid
  • Fatty acid
  • Fatty acyl
  • Amino acid
  • Carboxylic acid
  • Monocarboxylic acid or derivatives
  • Thioether
  • Sulfenyl compound
  • Dialkylthioether
  • Amine
  • Organic oxygen compound
  • Primary amine
  • Organosulfur compound
  • Organooxygen compound
  • Organonitrogen compound
  • Organic nitrogen compound
  • Primary aliphatic amine
  • Carbonyl group
  • Organopnictogen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
Biological Properties
StatusDetected and Not Quantified
Cellular Locations
  • Extracellular
  • Membrane
Biofluid LocationsNot Available
Tissue Locations
  • Fibroblasts
  • Kidney
  • Liver
  • Muscle
  • Pancreas
  • Prostate
  • Spleen
Betaine MetabolismSMP00123 map00260
Glycine and Serine MetabolismSMP00004 map00260
Methionine MetabolismSMP00033 map00270
Spermidine and Spermine BiosynthesisSMP00445 Not Available
Transcription/TranslationSMP00019 Not Available
Cystathionine Beta-Synthase DeficiencySMP00177 Not Available
Glycine N-methyltransferase DeficiencySMP00222 Not Available
Homocystinuria-megaloblastic anemia due to defect in cobalamin metabolism, cblG complementation typeSMP00570 Not Available
HypermethioninemiaSMP00341 Not Available
Methionine Adenosyltransferase DeficiencySMP00221 Not Available
Methylenetetrahydrofolate Reductase Deficiency (MTHFRD)SMP00340 Not Available
S-Adenosylhomocysteine (SAH) Hydrolase DeficiencySMP00214 Not Available
Biological Roles
Chemical RolesNot Available
Physical Properties
AppearanceWhite powder.
Experimental Properties
Melting Point283 dec°C
Boiling PointNot Available
Solubility5.66E+004 mg/L (at 25°C)
Predicted Properties
Water Solubility23.9 g/LALOGPS
pKa (Strongest Acidic)2.53ChemAxon
pKa (Strongest Basic)9.5ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area63.32 ŲChemAxon
Rotatable Bond Count4ChemAxon
Refractivity37.59 m³·mol⁻¹ChemAxon
Polarizability15.5 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (2 TMS)splash10-004i-0920000000-945c85aa7c9f5eb2dfbbJSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (Non-derivatized)splash10-004i-0910000000-b837ee0f4413856560f1JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (2 TMS)splash10-00b9-7910000000-5a1558fbb2f5e86edc9bJSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-MS (1 TMS)splash10-0udi-1900000000-1a97567ce4f25c4e8263JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-MS (2 TMS)splash10-004i-0910000000-1b0477118cb20549bf4dJSpectraViewer | MoNA
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-004i-0920000000-8ffae5d87508e0704903JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-004i-0920000000-945c85aa7c9f5eb2dfbbJSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-004i-0910000000-b837ee0f4413856560f1JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-QQ (Non-derivatized)splash10-01bc-2692000000-c6a4af434abaeea2de87JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-00b9-7910000000-5a1558fbb2f5e86edc9bJSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-MS (Non-derivatized)splash10-0udi-1900000000-1a97567ce4f25c4e8263JSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-MS (Non-derivatized)splash10-004i-0910000000-1b0477118cb20549bf4dJSpectraViewer | MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0mbd-9200000000-77e5cfb78936ad02d71cJSpectraViewer
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-00di-9510000000-c03dec8575710eed861eJSpectraViewer
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-0uea-1900000000-b991859b2c5bed6592a8JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-08fr-9000000000-66855ace60e59837f131JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-08fr-9000000000-56a567791c824c6a9da6JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-0fe0-0900000000-d680295f21b2e2b40366JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-0006-9000000000-062d3540db4db22da836JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-00di-0900000000-84467513e2c9ec1a6851JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-001i-0900000000-88dc2bebb198eea550efJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-0udi-0920000000-b444ad79abeb16acde43JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-001i-0900000000-6e24a8df417e5f3db58cJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-00di-0900000000-c60ef880eb9a816a274bJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-000i-0900000000-a7b7d1a3481c0c691a5bJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 10V, Negativesplash10-0002-0900000000-9156f088f4cc9eafa892JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 20V, Negativesplash10-0002-9200000000-f78ba2aab8d5a0e0b135JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 30V, Negativesplash10-0002-9000000000-e7b819fd2d0ac3862860JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 40V, Negativesplash10-0002-9000000000-b61396e720381bd5ff85JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 50V, Negativesplash10-0002-9000000000-b61396e720381bd5ff85JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 10V, Positivesplash10-0udi-0900000000-c3557cb41fd6fe268819JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 20V, Positivesplash10-0udi-6900000000-6bf5af2d1c561013948aJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 30V, Positivesplash10-08fr-9000000000-63c9b1c138f9a27490e5JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 40V, Positivesplash10-03di-9000000000-e133c47b0efe4992589fJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 50V, Positivesplash10-03di-9000000000-dee78b4f34f8732fedb0JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - CE-ESI-TOF (CE-system connected to 6210 Time-of-Flight MS, Agilent) , Positivesplash10-0udi-0900000000-d3f03ff5e8eacc8b6c8eJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF (UPLC Q-Tof Premier, Waters) , Positivesplash10-0udi-0900000000-e0dd5ff44b7962f6a2d2JSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0udi-2900000000-305916dde72c899993b6JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0udi-9800000000-47e0a34a2ec02bd762bfJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
2D NMR[1H,1H] 2D NMR SpectrumNot AvailableJSpectraViewer
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableJSpectraViewer
Toxicity Profile
Route of ExposureAbsorbed from the lumen of the small intestine into the enterocytes by an active transport process.
Mechanism of ToxicityThe mechanism of the possible anti-hepatotoxic activity of L-methionine is not entirely clear. It is thought that metabolism of high doses of acetaminophen in the liver lead to decreased levels of hepatic glutathione and increased oxidative stress. L-methionine is a precursor to L-cysteine. L-cysteine itself may have antioxidant activity. L-cysteine is also a precursor to the antioxidant glutathione. Antioxidant activity of L-methionine and metabolites of L-methionine appear to account for its possible anti-hepatotoxic activity. Recent research suggests that methionine itself has free-radical scavenging activity by virtue of its sulfur, as well as its chelating ability.
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)No indication of carcinogenicity to humans (not listed by IARC).
Uses/SourcesUsed for protein synthesis including the formation of SAMe, L-homocysteine, L-cysteine, taurine, and sulfate.
Minimum Risk LevelNot Available
Health EffectsChronically high levels of methionine are associated with at least 7 inborn errors of metabolism including: Cystathionine Beta-Synthase Deficiency, Glycine N-methyltransferase Deficiency, Homocystinuria-megaloblastic anemia due to defect in cobalamin metabolism, Methionine Adenosyltransferase Deficiency, Methylenetetrahydrofolate reductase deficiency and S-Adenosylhomocysteine (SAH) Hydrolase Deficiency.
SymptomsNot Available
TreatmentNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDDB00134
PubChem Compound ID6137
ChemSpider ID5907
UniProt IDNot Available
ChEBI ID16643
CTD IDNot Available
Stitch IDNot Available
ACToR IDNot Available
Wikipedia LinkMET
Synthesis Reference

Clyde Eugene Stauffer, “Process for producing N-acyl-L-methionine.” U.S. Patent US3963573, issued June, 1950.

General References
  1. Ball RO, Courtney-Martin G, Pencharz PB: The in vivo sparing of methionine by cysteine in sulfur amino acid requirements in animal models and adult humans. J Nutr. 2006 Jun;136(6 Suppl):1682S-1693S. [16702340 ]
  2. van de Poll MC, Dejong CH, Soeters PB: Adequate range for sulfur-containing amino acids and biomarkers for their excess: lessons from enteral and parenteral nutrition. J Nutr. 2006 Jun;136(6 Suppl):1694S-1700S. [16702341 ]
  3. Garlick PJ: Toxicity of methionine in humans. J Nutr. 2006 Jun;136(6 Suppl):1722S-1725S. [16702346 ]
  4. Alme B, Bremmelgaard A, Sjovall J, Thomassen P: Analysis of metabolic profiles of bile acids in urine using a lipophilic anion exchanger and computerized gas-liquid chromatorgaphy-mass spectrometry. J Lipid Res. 1977 May;18(3):339-62. [864325 ]
  5. Sardharwalla IB, Fowler B, Robins AJ, Komrower GM: Detection of heterozygotes for homocystinuria. Study of sulphur-containing amino acids in plasma and urine after L-methionine loading. Arch Dis Child. 1974 Jul;49(7):553-9. [4851308 ]
  6. Peng CT, Wu KH, Lan SJ, Tsai JJ, Tsai FJ, Tsai CH: Amino acid concentrations in cerebrospinal fluid in children with acute lymphoblastic leukemia undergoing chemotherapy. Eur J Cancer. 2005 May;41(8):1158-63. Epub 2005 Apr 14. [15911239 ]
  7. Cynober LA: Plasma amino acid levels with a note on membrane transport: characteristics, regulation, and metabolic significance. Nutrition. 2002 Sep;18(9):761-6. [12297216 ]
  8. Rainesalo S, Keranen T, Palmio J, Peltola J, Oja SS, Saransaari P: Plasma and cerebrospinal fluid amino acids in epileptic patients. Neurochem Res. 2004 Jan;29(1):319-24. [14992292 ]
  9. Alton KB, Hernandez A, Alvarez N, Patrick JE: High-performance liquid chromatographic determination of N-[2(S)-(mercaptomethyl)-3-(2-methylphenyl)-1-oxopropyl]-L-methionine, the active plasma metabolite of a prodrug atriopeptidase inhibitor (SCH 42495), using a thiol selective (Au/Hg) amperometric detector. J Chromatogr. 1992 Sep 2;579(2):307-17. [1429978 ]
  10. Fischer JL, Lancia JK, Mathur A, Smith ML: Selenium protection from DNA damage involves a Ref1/p53/Brca1 protein complex. Anticancer Res. 2006 Mar-Apr;26(2A):899-904. [16619485 ]
  11. Kersemans V, Cornelissen B, Kersemans K, Bauwens M, Achten E, Dierckx RA, Mertens J, Slegers G: In vivo characterization of 123/125I-2-iodo-L-phenylalanine in an R1M rhabdomyosarcoma athymic mouse model as a potential tumor tracer for SPECT. J Nucl Med. 2005 Mar;46(3):532-9. [15750170 ]
  12. Shoemaker JD, Elliott WH: Automated screening of urine samples for carbohydrates, organic and amino acids after treatment with urease. J Chromatogr. 1991 Jan 2;562(1-2):125-38. [2026685 ]
  13. Ditscheid B, Funfstuck R, Busch M, Schubert R, Gerth J, Jahreis G: Effect of L-methionine supplementation on plasma homocysteine and other free amino acids: a placebo-controlled double-blind cross-over study. Eur J Clin Nutr. 2005 Jun;59(6):768-75. [15870821 ]
  14. Hesse A, Heimbach D: Causes of phosphate stone formation and the importance of metaphylaxis by urinary acidification: a review. World J Urol. 1999 Oct;17(5):308-15. [10552150 ]
  15. Engelborghs S, Marescau B, De Deyn PP: Amino acids and biogenic amines in cerebrospinal fluid of patients with Parkinson's disease. Neurochem Res. 2003 Aug;28(8):1145-50. [12834252 ]
  16. Harth G, Horwitz MA: Inhibition of Mycobacterium tuberculosis glutamine synthetase as a novel antibiotic strategy against tuberculosis: demonstration of efficacy in vivo. Infect Immun. 2003 Jan;71(1):456-64. [12496196 ]
  17. Takasu A, Shimosegawa T, Shimosegawa E, Hatazawa J, Kimura K, Fujita M, Koizumi M, Kanno I, Toyota T: 11C-methionine uptake to the pancreas and its secretion: a positron emission tomography study in humans. Pancreas. 1999 May;18(4):392-8. [10231845 ]
  18. Hagenfeldt L, Bjerkenstedt L, Edman G, Sedvall G, Wiesel FA: Amino acids in plasma and CSF and monoamine metabolites in CSF: interrelationship in healthy subjects. J Neurochem. 1984 Mar;42(3):833-7. [6198473 ]
  19. Sreekumar A, Poisson LM, Rajendiran TM, Khan AP, Cao Q, Yu J, Laxman B, Mehra R, Lonigro RJ, Li Y, Nyati MK, Ahsan A, Kalyana-Sundaram S, Han B, Cao X, Byun J, Omenn GS, Ghosh D, Pennathur S, Alexander DC, Berger A, Shuster JR, Wei JT, Varambally S, Beecher C, Chinnaiyan AM: Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression. Nature. 2009 Feb 12;457(7231):910-4. doi: 10.1038/nature07762. [19212411 ]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available


General Function:
Zinc ion binding
Specific Function:
Involved in the regulation of homocysteine metabolism. Converts betaine and homocysteine to dimethylglycine and methionine, respectively. This reaction is also required for the irreversible oxidation of choline.
Gene Name:
Uniprot ID:
Molecular Weight:
44998.205 Da
  1. Slow S, Garrow TA: Liver choline dehydrogenase and kidney betaine-homocysteine methyltransferase expression are not affected by methionine or choline intake in growing rats. J Nutr. 2006 Sep;136(9):2279-83. [16920841 ]
  2. Sparks JD, Collins HL, Chirieac DV, Cianci J, Jokinen J, Sowden MP, Galloway CA, Sparks CE: Hepatic very-low-density lipoprotein and apolipoprotein B production are increased following in vivo induction of betaine-homocysteine S-methyltransferase. Biochem J. 2006 Apr 15;395(2):363-71. [16396637 ]
  3. Uthus EO, Reeves PG, Saari JT: Copper deficiency decreases plasma homocysteine in rats. J Nutr. 2007 Jun;137(6):1370-4. [17513393 ]
  4. Liu J, Xie Y, Cooper R, Ducharme DM, Tennant R, Diwan BA, Waalkes MP: Transplacental exposure to inorganic arsenic at a hepatocarcinogenic dose induces fetal gene expression changes in mice indicative of aberrant estrogen signaling and disrupted steroid metabolism. Toxicol Appl Pharmacol. 2007 May 1;220(3):284-91. Epub 2007 Feb 6. [17350061 ]
  5. Hazra A, Wu K, Kraft P, Fuchs CS, Giovannucci EL, Hunter DJ: Twenty-four non-synonymous polymorphisms in the one-carbon metabolic pathway and risk of colorectal adenoma in the Nurses' Health Study. Carcinogenesis. 2007 Jul;28(7):1510-9. Epub 2007 Mar 26. [17389618 ]
General Function:
Poly(a) rna binding
Specific Function:
Cotranslationally removes the N-terminal methionine from nascent proteins. The N-terminal methionine is often cleaved when the second residue in the primary sequence is small and uncharged (Met-Ala-, Cys, Gly, Pro, Ser, Thr, or Val). The catalytic activity of human METAP2 toward Met-Val peptides is consistently two orders of magnitude higher than that of METAP1, suggesting that it is responsible for processing proteins containing N-terminal Met-Val and Met-Thr sequences in vivo.Protects eukaryotic initiation factor EIF2S1 from translation-inhibiting phosphorylation by inhibitory kinases such as EIF2AK2/PKR and EIF2AK1/HCR. Plays a critical role in the regulation of protein synthesis.
Gene Name:
Uniprot ID:
Molecular Weight:
52891.145 Da
  1. Upadhya R, Zhang HS, Weiss LM: System for expression of microsporidian methionine amino peptidase type 2 (MetAP2) in the yeast Saccharomyces cerevisiae. Antimicrob Agents Chemother. 2006 Oct;50(10):3389-95. Epub 2006 Aug 17. [16917013 ]
  2. Sheppard GS, Wang J, Kawai M, Fidanze SD, BaMaung NY, Erickson SA, Barnes DM, Tedrow JS, Kolaczkowski L, Vasudevan A, Park DC, Wang GT, Sanders WJ, Mantei RA, Palazzo F, Tucker-Garcia L, Lou P, Zhang Q, Park CH, Kim KH, Petros A, Olejniczak E, Nettesheim D, Hajduk P, Henkin J, Lesniewski R, Davidsen SK, Bell RL: Discovery and optimization of anthranilic acid sulfonamides as inhibitors of methionine aminopeptidase-2: a structural basis for the reduction of albumin binding. J Med Chem. 2006 Jun 29;49(13):3832-49. [16789740 ]
  3. Addlagatta A, Matthews BW: Structure of the angiogenesis inhibitor ovalicin bound to its noncognate target, human Type 1 methionine aminopeptidase. Protein Sci. 2006 Aug;15(8):1842-8. Epub 2006 Jul 5. [16823043 ]
  4. Hu X, Addlagatta A, Lu J, Matthews BW, Liu JO: Elucidation of the function of type 1 human methionine aminopeptidase during cell cycle progression. Proc Natl Acad Sci U S A. 2006 Nov 28;103(48):18148-53. Epub 2006 Nov 17. [17114291 ]
  5. Nonato MC, Widom J, Clardy J: Human methionine aminopeptidase type 2 in complex with L- and D-methionine. Bioorg Med Chem Lett. 2006 May 15;16(10):2580-3. Epub 2006 Mar 15. [16540317 ]
General Function:
Zinc ion binding
Specific Function:
Catalyzes the transfer of a methyl group from methyl-cobalamin to homocysteine, yielding enzyme-bound cob(I)alamin and methionine. Subsequently, remethylates the cofactor using methyltetrahydrofolate (By similarity).
Gene Name:
Uniprot ID:
Molecular Weight:
140525.91 Da
  1. Taurog RE, Matthews RG: Activation of methyltetrahydrofolate by cobalamin-independent methionine synthase. Biochemistry. 2006 Apr 25;45(16):5092-102. [16618098 ]
  2. Hughes JA: In vivo hydrolysis of S-adenosyl-L-methionine in Escherichia coli increases export of 5-methylthioribose. Can J Microbiol. 2006 Jun;52(6):599-602. [16788729 ]
  3. Reynolds E: Vitamin B12, folic acid, and the nervous system. Lancet Neurol. 2006 Nov;5(11):949-60. [17052662 ]
  4. Banks EC, Doughty SW, Toms SM, Wheelhouse RT, Nicolaou A: Inhibition of cobalamin-dependent methionine synthase by substituted benzo-fused heterocycles. FEBS J. 2007 Jan;274(1):287-99. [17222188 ]
  5. Yamada K, Kawata T, Wada M, Mori K, Tamai H, Tanaka N, Tadokoro T, Tobimatsu T, Toraya T, Maekawa A: Testicular injury to rats fed on soybean protein-based vitamin B12-deficient diet can be reduced by methionine supplementation. J Nutr Sci Vitaminol (Tokyo). 2007 Apr;53(2):95-101. [17615995 ]
General Function:
Oxidoreductase activity, oxidizing metal ions, nad or nadp as acceptor
Specific Function:
Involved in the reductive regeneration of cob(I)alamin (vitamin B12) cofactor required for the maintenance of methionine synthase in a functional state. Necessary for utilization of methylgroups from the folate cycle, thereby affecting transgenerational epigenetic inheritance. Folate pathway donates methyl groups necessary for cellular methylation and affects different pathways such as DNA methylation, possibly explaining the transgenerational epigenetic inheritance effects.
Gene Name:
Uniprot ID:
Molecular Weight:
80409.22 Da
  1. Kim DJ, Park BL, Koh JM, Kim GS, Kim LH, Cheong HS, Shin HD, Hong JM, Kim TH, Shin HI, Park EK, Kim SY: Methionine synthase reductase polymorphisms are associated with serum osteocalcin levels in postmenopausal women. Exp Mol Med. 2006 Oct 31;38(5):519-24. [17079868 ]
  2. Tvedegaard KC, Rudiger NS, Pedersen BN, Moller J: Detection of MTRR 66A-->G polymorphism using the real-time polymerase chain reaction machine LightCycler for determination of composition of allele after restriction cleavage. Scand J Clin Lab Invest. 2006;66(8):685-93. [17101561 ]
  3. Elmore CL, Wu X, Leclerc D, Watson ED, Bottiglieri T, Krupenko NI, Krupenko SA, Cross JC, Rozen R, Gravel RA, Matthews RG: Metabolic derangement of methionine and folate metabolism in mice deficient in methionine synthase reductase. Mol Genet Metab. 2007 May;91(1):85-97. Epub 2007 Mar 21. [17369066 ]
General Function:
Zinc ion binding
Specific Function:
Involved in the regulation of homocysteine metabolism. Converts homocysteine to methionine using S-methylmethionine (SMM) as a methyl donor.
Gene Name:
Uniprot ID:
Molecular Weight:
40353.84 Da
  1. Overington JP, Al-Lazikani B, Hopkins AL: How many drug targets are there? Nat Rev Drug Discov. 2006 Dec;5(12):993-6. [17139284 ]
  2. Imming P, Sinning C, Meyer A: Drugs, their targets and the nature and number of drug targets. Nat Rev Drug Discov. 2006 Oct;5(10):821-34. [17016423 ]