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Updated: Jul 31, 2026

Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry (CCMS)
Published on: December 20, 2010
Cobalamin-dependent methyltransferases
1Biophysics Research Division and Department of Biological Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
Abstract:
Cobalamin cofactors play critical roles in radical-catalyzed rearrangements and in methyl transfers. This Account focuses on the role of methylcobalamin and its structural homologues, the methylcorrinoids, as intermediaries in methyl transfer reactions, and particularly on the reaction catalyzed by cobalamin-dependent methionine synthase. In these methyl transfer reactions, the cobalt(I) form of the cofactor serves as the methyl acceptor. Biological methyl donors to cobalamin include N5-methyltetrahydrofolate, other methylamines, methanol, aromatic methyl ethers, acetate, and dimethyl sulfide. The challenge for chemists is to determine the enzymatic mechanisms for activation of these unreactive methyl donors and to mimic these amazing biological reactions.
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