INMT
Amine N-methyltransferase
Class of enzymes
Amine N-methyltransferase (EC 2.1.1.49), also called indolethylamine N-methyltransferase, and thioether S-methyltransferase, is an enzyme that is ubiquitously present in non-neural tissues and catalyzes the N-methylation of tryptamine and structurally related compounds.[1] More recently, it was discovered that this enzyme can also catalyze the methylation of thioether and selenoether compounds, although the physiological significance of this biotransformation is not yet known.[2][3]
The chemical reaction taking place is:
- S-adenosyl-L-methionine + an amine S-adenosyl-L-homocysteine + a methylated amine
Thus, the two substrates of this enzyme are S-adenosyl methionine and amine, whereas its two products are S-adenosylhomocysteine and methylated amine. In the case of tryptamine and serotonin these then become the dimethylated indolethylamines N,N-dimethyltryptamine (DMT) and bufotenine respectively.[4]
This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:amine N-methyltransferase. Other names in common use include nicotine N-methyltransferase, tryptamine N-methyltransferase, indolethylamine N-methyltransferase, and arylamine N-methyltransferase. This enzyme participates in tryptophan metabolism.
A wide range of primary, secondary and tertiary amines can act as acceptors, including tryptamine, aniline, nicotine and a variety of drugs and other xenobiotics.[1]