PROSITE documentation PDOC00844

NNMT/PNMT/TEMT family of methyltransferases signature


The following cytoplasmic vertebrate methyltransferases are evolutionary related [1,2]:

  • Nicotinamide N-methyltransferase (EC (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 xenobiotic compounds.
  • Phenylethanolamine N-methyltransferase (EC (PNMT). PNMT catalyzes the last step in catecholamine biosynthesis, the conversion of noradrenalin to adrenalin.
  • Indolethylamine N-methyltransferase (EC (INMT).
  • Thioether S-methyltransferase (EC (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.

Last update:

December 2001 / Pattern and text revised.

Technical section

PROSITE method (with tools and information) covered by this documentation:

NNMT_PNMT_TEMT, PS01100; NNMT/PNMT/TEMT family of methyltransferases signature  (PATTERN)


1AuthorsAksoy S., Szumlanski C.L., Weinshilboum R.M.
TitleHuman liver nicotinamide N-methyltransferase. cDNA cloning, expression, and biochemical characterization.
SourceJ. Biol. Chem. 269:14835-14840(1994).
PubMed ID8182091

2AuthorsThompson M.A., Moon E., Kim U.-J., Xu J., Siciliano M.J., Weinshilboum R.M.
TitleHuman indolethylamine N-methyltransferase: cDNA cloning and expression, gene cloning, and chromosomal localization.
SourceGenomics 61:285-297(1999).
PubMed ID10552930

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