In enzymology, a caffeoyl-CoA O-methyltransferase is an enzyme that catalyzes the chemical reaction S-adenosyl-L-methionine + caffeoyl-CoA ⇌ {\displaystyle \rightleftharpoons } S-adenosyl-L-homocysteine + feruloyl-CoAThus, the two substrates of this enzyme are S-adenosyl methionine and caffeoyl-CoA, whereas its two products are S-adenosylhomocysteine and feruloyl-CoA. Wikipedia