Translations:Vitamin B12/63/en

1. Isomerases

   Rearrangements in which a hydrogen atom is directly transferred between two adjacent atoms with concomitant exchange of the second substituent, X, which may be a carbon atom with substituents, an oxygen atom of an alcohol, or an amine. These use the adoB₁₂ (adenosylcobalamin) form of the vitamin.

2. Methyltransferases

   Methyl (–CH₃) group transfers between two molecules. These use the MeB₁₂ (methylcobalamin) form of the vitamin.

3. Dehalogenases

   Some species of anaerobic bacteria synthesize B₁₂-dependent dehalogenases, which have potential commercial applications for degrading chlorinated pollutants. The microorganisms may either be capable of de novo corrinoid biosynthesis or are dependent on exogenous vitamin B₁₂.