Reaction: L-carnitine + a [Co(I) quaternary-amine-specifc corrinoid protein] = a [methyl-Co(III) quaternary-amine-specific corrinoid protein] + L-norcarnitine
Glossary: L-norcarnitine = (3R)-4-(dimethylamino)-3-hydroxybutanoate
Other name(s): mtcB (gene name)
Systematic name: L-carnitine:[Co(I) quaternary-amine-specifc corrinoid protein] Co-methyltransferase
Comments: The enzyme, characterized from the bacterium Eubacterium limosum, is a component of a system that transfers a methyl group from L-carnitine to tetrahydrofolate, as part of an L-carnitine degradation pathway. The resulting 5-methyltetrahydrofolate is processed to acetyl-CoA via the Wood—Ljungdahl pathway.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Kountz, D.J., Behrman, E.J., Zhang, L. and Krzycki, J.A. MtcB, a member of the MttB superfamily from the human gut acetogen Eubacterium limosum, is a cobalamin-dependent carnitine demethylase. J. Biol. Chem. 295 (2020) 11971-11981. [PMID: 32571881]