a catechol + S-adenosyl-L-methionine = a guaiacol + S-adenosyl-L-homocysteine + H(+)
a catechol + s-adenosyl-l-methionine = a guaiacol + s-adenosyl-l-homocysteine + h(+)
"catechol O-methyltransferase"
"catechol o-methyltransferase"