. "Catalysis of the reaction: (S)-tetrahydrocolumbamine + S-adenosyl-L-methionine(1+) = S-adenosyl-L-homocysteine + H(+) + tetrahydropalmatine." . . "tetrahydrocolumbamine 2-O-methyltransferase activity" . "S-adenosyl-L-methionine:5,8,13,13a-tetrahydrocolumbamine 2-O-methyltransferase activity" . "tetrahydrocolumbamine methyltransferase activity" . . .