Methylation pathways (WP704)

Homo sapiens

This pathway describes the addition of methyl groups to small molecules. SAM, S-Adenosyl methionine, is utilized as a methyl donor and SAH is produced. This process is important in drug metabolism. Proteins on this pathway have targeted assays available via the [ CPTAC Assay Portal]


Pieter Giesbertz , Kristina Hanspers , Alex Pico , Martijn Van Iersel , Zahra Roudbari , Marianthi Kalafati , and Eric Weitz


last edited

Discuss this pathway

Check for ongoing discussions or start your own.

Cited In

Are you planning to include this pathway in your next publication? See How to Cite and add a link here to your paper once it's online.


Homo sapiens




Pathway Ontology

classic metabolic pathway protein modification pathway


Label Type Compact URI Comment
Phosphate Metabolite hmdb:HMDB0001429
S-Adenosylhomocysteine Metabolite hmdb:HMDB0000939
S-Adenosylmethionine Metabolite hmdb:HMDB0001185
ATP Metabolite hmdb:HMDB0000538
S-Adenosylmethionine Metabolite hmdb:HMDB0001185
L-Methionine Metabolite hmdb:HMDB0000696
Phosphate Metabolite hmdb:HMDB0001429
S-Adenosylmethionine Metabolite hmdb:HMDB0001185
S-Adenosylhomocysteine Metabolite hmdb:HMDB0000939
S-Adenosylhomocysteine Metabolite hmdb:HMDB0000939
MAT1A GeneProduct ensembl:ENSG00000151224
MAT2A GeneProduct ensembl:ENSG00000168906
TPMT GeneProduct ensembl:ENSG00000137364
PNMT GeneProduct ensembl:ENSG00000141744
MAT2B GeneProduct ensembl:ENSG00000038274
HNMT GeneProduct ensembl:ENSG00000150540
INMT GeneProduct ensembl:ENSG00000241644
NNMT GeneProduct ensembl:ENSG00000166741
COMT GeneProduct ensembl:ENSG00000093010


  1. Pharmacogenomics: catechol O-methyltransferase to thiopurine S-methyltransferase. Weinshilboum RM. Cell Mol Neurobiol. 2006;26(4–6):539–61. PubMed Europe PMC Scholia
  2. The biochemistry of drug metabolism--an introduction: part 4. reactions of conjugation and their enzymes. Testa B, Krämer SD. Chem Biodivers. 2008 Nov;5(11):2171–336. PubMed Europe PMC Scholia