The double mutant Mut3 is the most active variant in the methylation of 2b, but converts resveratrol and pinostilbene poorly and has similar activity to the wildtype towards 2c and 2d. Both, 2c and 2d have a larger hydrophobic surface, which can possibly facilitate the accommodation of the substrate in the active site. Furthermore, the electron-pushing effect of the methoxy groups on the aromatic ring increases the nucleophilicity in the attack on the reactive methyl group of S-adenosylmethionine (SAM).