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Record Information
StatusDetected and Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2018-04-16 17:02:03 UTC
Secondary Accession Numbers
  • HMDB0003610
  • HMDB00379
  • HMDB03610
Metabolite Identification
Common Name2-Methylcitric acid
DescriptionMethylcitric acid (MCA) is elevated in body fluids of patients with propionic acidaemia (PA; OMIM 232000 , 232050 ), methylmalonic aciduria (MMA; OMIM 251000 , 251120 ) and multiple carboxylase deficiency (OMIM 253260 , 253270 ), which are inherited disorders. MCA is formed by condensation of accumulated propionyl- CoA and oxalacetate by the enzyme si-citrate synthase (EC MCA molecule has two stereogenic centers so that it can occur in the form of four stereoisomers. Only two stereoisomers of MCA, (2S, 3S) and (2R, 3S), were found in human urine (PMID: 17295121 ).
2-Hydroxy-1,2,3-butanetricarboxylic acidChEBI
2-Hydroxybutane-1,2,3-tricarboxylic acidHMDB
2-Methylcitric acid, 3H-labeledMeSH
3-Carboxy-3-hydroxy-2-methylpentanedioic acidMeSH
Methylcitric acidMeSH
Chemical FormulaC7H10O7
Average Molecular Weight206.1501
Monoisotopic Molecular Weight206.042652674
IUPAC Name2-hydroxy-1-methylpropane-1,2,3-tricarboxylic acid
Traditional Namemethylcitric acid
CAS Registry Number6061-96-7
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as tricarboxylic acids and derivatives. These are carboxylic acids containing exactly three carboxyl groups.
KingdomOrganic compounds
Super ClassOrganic acids and derivatives
ClassCarboxylic acids and derivatives
Sub ClassTricarboxylic acids and derivatives
Direct ParentTricarboxylic acids and derivatives
Alternative Parents
  • Tricarboxylic acid or derivatives
  • Hydroxy acid
  • Alpha-hydroxy acid
  • Tertiary alcohol
  • Carboxylic acid
  • Organic oxygen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Organooxygen compound
  • Carbonyl group
  • Alcohol
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors


Biological location:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility175 g/LALOGPS
pKa (Strongest Acidic)3.18ChemAxon
pKa (Strongest Basic)-4.3ChemAxon
Physiological Charge-3ChemAxon
Hydrogen Acceptor Count7ChemAxon
Hydrogen Donor Count4ChemAxon
Polar Surface Area132.13 ŲChemAxon
Rotatable Bond Count5ChemAxon
Refractivity40.2 m³·mol⁻¹ChemAxon
Polarizability17.21 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0hhi-3900000000-c705fb286a4c575f9852View in MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (4 TMS) - 70eV, Positivesplash10-00b9-8029800000-dc9ef9d5a5a220f1ae9fView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-000i-0900000000-be0da5c29220e9e50325View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-05i0-9600000000-2bead66ba2514df6497fView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-1093-7900000000-e7a5530b8562d859e032View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0900-1910000000-0a84eb8e0df2e6eb450dView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-07vi-4900000000-e89ea7de4d7e433cae1eView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4i-9300000000-c68ffdf8bf6f5380005eView in MoNA
Biological Properties
Cellular Locations
  • Extracellular
Biospecimen Locations
  • Blood
  • Cerebrospinal Fluid (CSF)
  • Feces
  • Urine
Tissue LocationNot Available
PathwaysNot Available
Normal Concentrations
BloodDetected and Quantified0.1 (0.08-0.26) uMAdult (>18 years old)BothNormal details
BloodDetected and Quantified0.059 (0.021-0.097) uMAdult (>18 years old)BothNormal details
Cerebrospinal Fluid (CSF)Detected and Quantified0.323-1.07 uMNot SpecifiedNot SpecifiedNormal details
Cerebrospinal Fluid (CSF)Detected and Quantified0.50 (0.24-0.80) uMAdult (>18 years old)BothNormal details
FecesDetected but not Quantified Adult (>18 years old)Both
UrineDetected and Quantified1.4-2.9 umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified<15 umol/mmol creatinineAdult (>18 years old)BothNormal details
UrineDetected and Quantified6.7 (0.7-19.6) umol/mmol creatinineNewborn (0-30 days old)BothNormal details
UrineDetected and Quantified7.7 (3.3-28.6) umol/mmol creatinineInfant (0-1 year old)BothNormal details
UrineDetected and Quantified3.4 (1.4-8.5) umol/mmol creatinineChildren (1-13 years old)Both
UrineDetected and Quantified3.2 (2.0-8.1) umol/mmol creatinineChildren (1-13 years old)Both
UrineDetected and Quantified2.6 (1.6-6.2) umol/mmol creatinineAdolescent (13-18 years old)BothNormal details
UrineDetected and Quantified1.2-1.8 umol/mmol creatinineAdult (>18 years old)MaleNormal details
UrineDetected and Quantified<6.09 umol/mmol creatinineChildren (1 - 18 years old)Both
    • BC Children's Hos...
UrineDetected and Quantified0.59 (0.05-1.15) umol/mmol creatinineAdult (>18 years old)BothNormal details
Abnormal Concentrations
Cerebrospinal Fluid (CSF)Detected and Quantified1.37-16.3 uMNot SpecifiedNot Specifiedcobalamin deficiency details
FecesDetected but not Quantified Adult (>18 years old)BothCrohns disease details
FecesDetected but not Quantified Adult (>18 years old)Bothnon-inflamed (NI) control anaemic details
UrineDetected and Quantified31 umol/mmol creatinineAdult (>18 years old)Not Specified
Propionic acidemia
UrineDetected and Quantified0.780-3.600 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
isovaleric acidemia
UrineDetected and Quantified1.470-1.560 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
isovaleric acidemia
UrineDetected and Quantified7.0 (2.0-12.0) umol/mmol creatinineAdult (>18 years old)BothBiotinidase deficiency
    • MetaGene: Metabol...
UrineDetected and Quantified30.0 (10.0-50.0) umol/mmol creatinineChildren (1-13 years old)BothBiotinidase deficiency
    • MetaGene: Metabol...
Associated Disorders and Diseases
Disease References
Biotinidase deficiency
  1. G.Frauendienst-Egger, Friedrich K. Trefz (2017). MetaGene: Metabolic & Genetic Information Center (MIC: METAGENE consortium.
Propionic acidemia
  1. Riemersma M, Hazebroek MR, Helderman-van den Enden ATJM, Salomons GS, Ferdinandusse S, Brouwers MCGJ, van der Ploeg L, Heymans S, Glatz JFC, van den Wijngaard A, Krapels IPC, Bierau J, Brunner HG: Propionic acidemia as a cause of adult-onset dilated cardiomyopathy. Eur J Hum Genet. 2017 Nov;25(11):1195-1201. doi: 10.1038/ejhg.2017.127. Epub 2017 Aug 30. [PubMed:28853722 ]
Associated OMIM IDs
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FoodDB IDFDB021997
KNApSAcK IDNot Available
Chemspider ID500
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG ID39369
Wikipedia LinkNot Available
PubChem Compound515
PDB IDNot Available
ChEBI ID30835
Synthesis ReferenceEwering, Christian; Braemer, Christian Oliver; Steinbuechel, Alexander. Production of 2-methylcitric acid by a recombinant Ralstonia eutropha strain. PCT Int. Appl. (2007), 30pp. CODEN: PIXXD2 WO 2007101866 A2 20070913 CAN 147:363646 AN 2007:1033111
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Guneral F, Bachmann C: Age-related reference values for urinary organic acids in a healthy Turkish pediatric population. Clin Chem. 1994 Jun;40(6):862-6. [PubMed:8087979 ]
  2. Allen RH, Stabler SP, Savage DG, Lindenbaum J: Elevation of 2-methylcitric acid I and II levels in serum, urine, and cerebrospinal fluid of patients with cobalamin deficiency. Metabolism. 1993 Aug;42(8):978-88. [PubMed:8345822 ]
  3. Busch M, Stein G, Poppitz W, Hein G, Muller A: Validated capillary gas chromatographic-mass spectrometric assay to determine 2-methylcitric acid I and II levels in human serum by using a pulsed splitless injection procedure. J Chromatogr B Analyt Technol Biomed Life Sci. 2002 Aug 5;775(2):215-23. [PubMed:12113988 ]
  4. Bergstrom T, Greter J, Levin AH, Steen G, Tryding N, Wass U: Propionyl-CoA carboxylase deficiency: case report, effect of low-protein diet and identification of 3-oxo-2-methylvaleric acid 3-hydroxy-2-methylvaleric acid, and maleic acid in urine. Scand J Clin Lab Invest. 1981 Apr;41(2):117-26. [PubMed:7313494 ]
  5. Thompson GN, Chalmers RA: Increased urinary metabolite excretion during fasting in disorders of propionate metabolism. Pediatr Res. 1990 Apr;27(4 Pt 1):413-6. [PubMed:2342832 ]
  6. Krawczyk H, Gradowska W: 1H NMR spectra of methylcitric acid in urine. J Inherit Metab Dis. 2007 Apr;30(2):263. Epub 2007 Feb 14. [PubMed:17295121 ]