Reaction: S-adenosyl-L-methionine + 3,4-dihydroxy-trans-cinnamate = S-adenosyl-L-homocysteine + 3-methoxy-4-hydroxy-trans-cinnamate
Other name(s): caffeate methyltransferase; caffeate 3-O-methyltransferase; S-adenosyl-L-methionine:caffeic acid-O-methyltransferase
Systematic name: S-adenosyl-L-methionine:3,4-dihydroxy-trans-cinnamate 3-O-methyltransferase
Comments: 3,4-Dihydroxybenzaldehyde and catechol can act as acceptors, but more slowly.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 50936-45-3
References:
1. Ebel, J., Schaller-Hekeler, B., Knobloch, K.-H., Wellman, E., Grisebach, H. and Hahlbrock, K. Coordinated changes in enzyme activities of phenylpropanoid metabolism during the growth of soybean cell suspension cultures. Biochim. Biophys. Acta 362 (1974) 417-424. [PMID: 4472044]
2. Poulton, J.E. and Butt, V.S. Purification and properties of S-adenosyl-L-methionine: caffeic acid O-methyltransferase from leaves of spinach beet (Beta vulgaris L). Biochim. Biophys. Acta 403 (1975) 301-314. [PMID: 241400]
3. Shimada, M., Kuroda, H. and Higuchi, T. Evidence for the formation of methoxyl groups of ferulic and sinapic acid in Bambusa by the same O-methyltransferase. Phytochemistry 12 (1973) 2873-2875.