You are using an unsupported browser. Please upgrade your browser to a newer version to get the best experience on Human Metabolome Database.
Record Information
Creation Date2006-05-22 14:17:45 UTC
Update Date2017-03-02 21:26:57 UTC
Secondary Accession NumbersNone
Metabolite Identification
Common NameMethylcobalamin
DescriptionThe name vitamin B12 is used in two different ways. In a broad sense it refers to a group of cobalt-containing compounds known as cobalamins - cyanocobalamin (an artifact formed as a result of the use of cyanide in the purification procedures), hydroxocobalamin and the two coenzyme forms of B12, methylcobalamin (MeB12) and 5-deoxyadenosylcobalamin (adenosylcobalamin - AdoB12). In a more specific way, the term B12 is used to refer to only one of these forms, cyanocobalamin, which is the principal B12 form used for foods and in nutritional supplements. B12 cannot be made by plants or by animals, as the only type of organisms that have the enzymes required for the synthesis of B12 are bacteria and archaea. The total synthesis of B12 was reported in 1973 by Robert Burns Woodward, and remains one of the classic feats of total synthesis. Cyanocobalamin is a vitamin commonly known as vitamin B12 (or B12 for short).
Hitocobamin mHMDB
Methyl cobalamineHMDB
Methyl vitamin b12HMDB
Chemical FormulaC63H91CoN13O14P
Average Molecular Weight1344.3823
Monoisotopic Molecular Weight1343.587806391
IUPAC NameNot Available
Traditional NameNot Available
CAS Registry Number13422-55-4
InChI Identifier
Chemical Taxonomy
ClassificationNot classified
StatusDetected and Quantified
  • Endogenous
BiofunctionNot Available
ApplicationNot Available
Cellular locationsNot Available
Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Physiological Charge2ChemAxon
Hydrogen Acceptor Count0ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area479.24 Å2ChemAxon
Rotatable Bond Count16ChemAxon
Refractivity353.78 m3·mol-1ChemAxon
Polarizability135.98 Å3ChemAxon
Number of Rings12ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
SpectraNot Available
Biological Properties
Cellular LocationsNot Available
Biofluid Locations
  • Cerebrospinal Fluid (CSF)
Tissue Location
  • Fibroblasts
  • Myelin
PathwaysNot Available
Normal Concentrations
Cerebrospinal Fluid (CSF)Detected and Quantified0.000220 +/- 8.410e-05 uMAdult (>18 years old)FemaleNormal details
Abnormal Concentrations
Cerebrospinal Fluid (CSF)Detected and Quantified0.000221 +/- 8.983e-05 uMAdult (>18 years old)Not Specifiedfibromyalgia details
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
DrugBank Metabolite IDNot Available
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDFDB022939
KNApSAcK IDNot Available
Chemspider IDNot Available
KEGG Compound IDC06453
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkMethylcobalamin
NuGOwiki LinkHMDB02274
Metagene LinkHMDB02274
PubChem CompoundNot Available
PDB IDNot Available
ChEBI ID28115
Synthesis ReferenceTollinger, Martin; Derer, Tomas; Konrat, Robert; Kraeutler, Bernhard. An efficient method for the preparation of methylcobalamin, nature's organometallic methyl transfer catalyst. Journal of Molecular Catalysis A: Chemical (1997), 116(1-2), 147-155.
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Koyama K, Usami T, Takeuchi O, Morozumi K, Kimura G: Efficacy of methylcobalamin on lowering total homocysteine plasma concentrations in haemodialysis patients receiving high-dose folic acid supplementation. Nephrol Dial Transplant. 2002 May;17(5):916-22. [11981084 ]
  2. Roze E, Gervais D, Demeret S, Ogier de Baulny H, Zittoun J, Benoist JF, Said G, Pierrot-Deseilligny C, Bolgert F: Neuropsychiatric disturbances in presumed late-onset cobalamin C disease. Arch Neurol. 2003 Oct;60(10):1457-62. [14568819 ]
  3. Frisbie SM, Chance MR: Human cobalophilin: the structure of bound methylcobalamin and a functional role in protecting methylcobalamin from photolysis. Biochemistry. 1993 Dec 21;32(50):13886-92. [8268164 ]
  4. Suormala T, Baumgartner MR, Coelho D, Zavadakova P, Kozich V, Koch HG, Berghauser M, Wraith JE, Burlina A, Sewell A, Herwig J, Fowler B: The cblD defect causes either isolated or combined deficiency of methylcobalamin and adenosylcobalamin synthesis. J Biol Chem. 2004 Oct 8;279(41):42742-9. Epub 2004 Aug 2. [15292234 ]
  5. Weinberg JB, Sauls DL, Misukonis MA, Shugars DC: Inhibition of productive human immunodeficiency virus-1 infection by cobalamins. Blood. 1995 Aug 15;86(4):1281-7. [7632933 ]
  6. Murayama K, Katsumi T, Asai T: [Clinical evaluation of micturitional dysfunction after the operation for rectal cancer and effects of mecobalamin on that dysfunction] Hinyokika Kiyo. 1989 Nov;35(11):1853-7. [2694825 ]
  7. Ramsey RB, Scott T, Banik NL: Fatty acid composition of myelin isolated from the brain of a patient with cellular deficiency of co-enzyme forms of vitamin B12. J Neurol Sci. 1977 Nov;34(2):221-32. [925711 ]
  8. van Kapel J, Spijkers LJ, Lindemans J, Abels J: Improved distribution analysis of cobalamins and cobalamin analogues in human plasma in which the use of thiol-blocking agents is a prerequisite. Clin Chim Acta. 1983 Jul 15;131(3):211-24. [6883715 ]
  9. el Kholty S, Gueant JL, Bressler L, Djalali M, Boissel P, Gerard P, Nicolas JP: Portal and biliary phases of enterohepatic circulation of corrinoids in humans. Gastroenterology. 1991 Nov;101(5):1399-408. [1936810 ]


General function:
Involved in cobalamin 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: