Methyltransferase (MTase)

Methyltransferases are a diverse group of enzymes that catalyze the transfer of methyl groups to various substrates, including proteins, nucleic acids (DNA and RNA), small molecules, and natural products. This methylation process is fundamental in regulating biological processes such as gene expression, epigenetic modification, metabolism, and cellular signaling. They are classified based on structural features (Class I, II, III) or substrate specificity (protein, DNA/RNA, natural product). Most utilize S-adenosyl methionine (SAM) as a cofactor, employing an SN2-like mechanism for methyl transfer. Aberrant activity is linked to various diseases, making them important drug targets.

Other names

MethyltransferasesMTsSAM-dependent methyltransferaseDNA methyltransferaseProtein methyltransferaseRNA methyltransferaseHistone methyltransferaseNatural product methyltransferase

SN2-like direct transfer of a methyl group from S-adenosyl methionine (SAM) to an acceptor atom/group on the substrate, converting SAM to S-adenosyl homocysteine (SAH).