SAM-dependent methyltransferase gTMT-type (IPR025774)

Short name: MTs_g-TMT

Overlapping homologous superfamilies

Family relationships



This entry represents a subgroup of the class I SAM-dependent methyltransferases, including bacterial 2-methyl-6-phytyl-1,4-hydroquinone methyltransferase [PMID: 11821038] and plant plastid tocopherol O-methyltransferase (also known as g-TMT (gamma-tocopherol methyltransferase)). Tocopherol O-methyltransferase is involved in the synthesis of tocopherol (vitamin E). It methylates gamma- and delta-tocopherol to form beta- and alpha-tocopherol, respectively [PMID: 9851934, PMID: 14682617, PMID: 12586887]. This family also includes 3-hydroxy-16-methoxy-2,3-dihydrotabersonine N-methyltransferase, an homologue of tocopherol methyltransferases involved in vindoline biosynthesis [PMID: 20956330].

Methyltransferases (EC 2.1.1.-) constitute an important class of enzymes present in every life form. They transfer a methyl group most frequently from S-adenosyl L-methionine (SAM or AdoMet) to a nucleophilic acceptor such as oxygen leading to S-adenosyl-L-homocysteine (AdoHcy) and a methylated molecule [PMID: 16225687, PMID: 21858014, PMID: 12826405]. All these enzymes have in common a conserved region of about 130 amino acid residues that allow them to bind SAM [PMID: 7897657]. The substrates that are methylated by these enzymes cover virtually every kind of biomolecules ranging from small molecules, to lipids, proteins and nucleic acids [PMID: 16225687, PMID: 21858014, PMID: 7897657]. Methyltransferase are therefore involved in many essential cellular processes including biosynthesis, signal transduction, protein repair, chromatin regulation and gene silencing [PMID: 16225687, PMID: 21858014, PMID: 12826405]. More than 230 families of methyltransferases have been described so far, of which more than 220 use SAM as the methyl donor.

GO terms

Biological Process

GO:0032259 methylation

Molecular Function

GO:0008168 methyltransferase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

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