BHMT2 tetramer transfers CH3 group from SMM to LHCYS

Stable Identifier
R-HSA-5696838
Type
Reaction [transition]
Species
Homo sapiens
Compartment
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L-homocysteine (LHCYS) is derived from L-methionine (L-Met) and can either be remethylated to reform L-Met or take part in cysteine biosynthesis via the trans-sulfuration pathway. LHCYS remethylation can occur by the action of two enzymes; cobalamin-dependent methionine synthase and betaine-homocysteine methyltransferase, using methyltetrahydrofolate and betaine respectively as methyl donors. A third enzyme, S-methylmethionine-homocysteine S-methyltransferase (BHMT2), can use S-methylmethionine (SMM) as the methyl donor to methylate LHCYS and reform L-Met. BHMT2 is a tetrameric, cytosolic enzyme that requires one Zn2+ ion per subunit as cofactor (Szegedi et al. 2008).

Literature References
PubMed ID Title Journal Year
18230605 Betaine-homocysteine S-methyltransferase-2 is an S-methylmethionine-homocysteine methyltransferase

Szegedi, SS, Castro, CC, Koutmos, M, Garrow, TA

J. Biol. Chem. 2008
Participants
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Catalyst Activity
Catalyst Activity
Title
S-methylmethionine-homocysteine S-methyltransferase activity of BHMT2:Zn2+ tetramer [cytosol]
Physical Entity
Activity
Orthologous Events
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Created