Methylcobalamin

Methylcobalamin

Methylcobalamin
Systematic (IUPAC) name
carbanide; cobalt(3+);
Clinical data
AHFS/Drugs.com
Legal status
Routes of
administration
oral,sublingual,injection.
Identifiers
CAS Registry Number  Y
ATC code B03
PubChem CID:
UNII  N
ChEMBL  N
Chemical data
Formula C63H91CoN13O14P
Molecular mass 1344.40 g/mol
 N   

Methylcobalamin (mecobalamin, MeCbl, or MeB12) is a cobalamin, a form of vitamin B12. It differs from cyanocobalamin in that the cyanide is replaced by a methyl group.[1] Methylcobalamin features an octahedral cobalt(III) centre. Methylcobalamin can be obtained as bright red crystals.[2] From the perspective of coordination chemistry, methylcobalamin is notable as a rare example of a compound that contains metal-alkyl bonds. Nickel-methyl intermediates have been proposed for the final step of methanogenesis.

Methylcobalamin is equivalent physiologically to vitamin B12, and can be used to prevent or treat pathology arising from a lack of vitamin B12 (vitamin B12 deficiency), such as pernicious anemia.

Methylcobalamin is also used in the treatment of peripheral neuropathy, diabetic neuropathy, and as a preliminary treatment for amyotrophic lateral sclerosis.

Contents

  • Production 1
  • Functions 2
  • See also 3
  • References 4

Production

Methylcobalamin physically resembles the other forms of vitamin B12, occurring as dark red crystals that freely form cherry-colored transparent solutions in water.

Methylcobalamin can be produced in the laboratory by reducing cyanocobalamin with sodium borohydride in alkaline solution, followed by the addition of methyl iodide.[2]

Functions

This vitamer is one of two active coenzymes used by vitamin B12-dependent enzymes and is the specific vitamin B12 form used by 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR), also known as methionine synthase.

Methylcobalamin participates in the

  1. ^ L. R. McDowell, Vitamins in animal and human nutrition 
  2. ^ a b David Dophin. Preparation of the Reduced Forms of Vitamin B12 and of Some Analogs of the Vitamin B12 Coenzyme Containing a Cobalt-Carbon Bond. D.B. McCormick and L.D. Wright, Eds. 1971;Vol. XVIII:34-54.
  3. ^ Fontecilla-Camps, J. C.; Amara, P.; Cavazza, C.; Nicolet, Y.; Volbeda, A. (2009). "Structure–function relationships of anaerobic gas-processing metalloenzymes". Nature 460 (7257): 814–822.  
  4. ^ Zenon Schneider, Andrzej Stroiński, Comprehensive B12: Chemistry, Biochemistry, Nutrition, Ecology, Medicine 
  5. ^ Bémeur, Chantal; et al. (2011). Blass, John P., ed. Neurochemical Mechanisms in Disease. Springer. pp. 112–3. 

References

See also

A lack of methylcobalamin can lead to megaloblastic anemia and subacute combined degeneration of the spinal cord.[5]

Methylcobalamin is produced by some bacteria. It plays an important role in the environment. In the environment, it is responsible for the biomethylation of certain heavy metals. For example, the highly toxic methylmercury is produced by the action of methylcobalamin.[4] In this role, methylcobalamin serves as a source of "CH3+".

[3]