Domain

Homocysteine S-methyltransferase (IPR003726)

Short name: S_MeTrfase

Domain relationships

None.

Description

S-methylmethionine: homocysteine methyltransferase EC:2.1.1.10 from Escherichia coli accepts selenohomocysteine as a substrate. S-methylmethionine is an abundant plant product that can be utilised for methionine biosynthesis [PMID: 9882684]. Human methionine synthase (5-methyltetrahydrofolate:L-homocysteine S-transmethylase; EC:2.1.1.13) shares 53 and 63% identity with the E. coli and the presumptive Caenorhabditis elegans proteins, respectively, and contains all residues implicated in B12 binding to the E. coli protein [PMID: 9013615]. Betaine--homocysteine S-methyltransferase (EC:2.1.1.5) converts betaine and homocysteine to dimethylglycine and methionine, respectively. This reaction is also required for the irreversible oxidation of choline [PMID: 8798461].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0008898 S-adenosylmethionine-homocysteine S-methyltransferase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
Pfam
GENE3D
SUPERFAMILY
PROSITE profiles