The following cytoplasmic vertebrate methyltransferases are evolutionary
Nicotinamide N-methyltransferase (EC 184.108.40.206) (NNMT). NNMT catalyzes the N-
methylation of nicotinamide and other pyridines to form pyridinium ions.
This activity is important for the biotransformation of many drugs and
Phenylethanolamine N-methyltransferase (EC 220.127.116.11) (PNMT). PNMT catalyzes
the last step in catecholamine biosynthesis, the conversion of noradrenalin
Thioether S-methyltransferase (EC 18.104.22.168) (TEMT). TEMT catalyzes the
methylation of dimethyl sulfide into trimethylsulfonium.
These enzymes use S-adenosyl-L-methionine as the methyl donor. They are
proteins of 30 to 32 Kd. As a signature pattern we selected the most conserved
region, a stretch of 16 residues which are located in the N-terminal section
of these enzymes.
December 2001 / Pattern and text revised.
PROSITE method (with tools and information) covered by this documentation:
Aksoy S., Szumlanski C.L., Weinshilboum R.M.
Human liver nicotinamide N-methyltransferase. cDNA cloning, expression, and biochemical characterization.
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