Reaction: S-adenosyl-L-methionine + columbamine = S-adenosyl-L-homocysteine + palmatine
For diagram click here.
Systematic name: S-adenosyl-L-methionine:columbamine O-methyltransferase
Comments: the product of this reaction is a protoberberine alkaloid that is widely distributed in the plant kingdom. This enzyme is distinct in specificity from EC 188.8.131.52, 8-hydroxyquercetin 8-O-methyltransferase.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 105843-76-3
1. Rueffer, M., Amann, M., Zenk, M.H. S-Adenosyl-L-methionine:columbamine O-methyltransferase, a compartmentalized enzyme in protoberberine biosynthesis. Plant Cell Reports 3 (1986) 182-185.