MTR transfers CH3 group from MTHF to cob(I)alamin

Stable Identifier
Reaction [transition]
Homo sapiens
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Methionine synthase (MTR) catalyses the transfer of a methyl group from 5-methyltetrahydrofolate (MTHF) to homocysteine (HCYS) to then form methionine (L-Met). In the first step, MTR mediates the transfer of a methyl group from 5-methyltetrahydrofolate (MTHF) to cob(I)alamin (B12s, bound to the enzyme MTR) to form the cofactor methylcobalamin (MeCbl), the form that activates MTR (Leclerc et al. 1996). Defects in MTR cause methylcobalamin deficiency type G (cblG, methionine synthase deficiency; MIM:250940), an autosomal recessive inherited disease that causes mental retardation, macrocytic anemia, and homocystinuria (Leclerc et al. 1996).

Literature References
PubMed ID Title Journal Year
8968737 Human methionine synthase: cDNA cloning and identification of mutations in patients of the cblG complementation group of folate/cobalamin disorders

Leclerc, D, Campeau, E, Goyette, P, Adjalla, CE, Christensen, B, Ross, M, Eydoux, P, Rosenblatt, DS, Rozen, R, Gravel, RA

Hum Mol Genet 1996
Catalyst Activity

methionine synthase activity of MTRR:MTR(cob(I)alamin) [cytosol]

Orthologous Events
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