Fig. 6

Predicted substrate binding sites in CkOMT4 (pink) and CsOMT5 (green). Orange sticks, the co-product S-adenosylhomocysteine (SAH); blue sticks, the substrate (emodin 1 for CkOMT4 and endocrocin 2 for CsOMT5); yellow sticks, the predicted catalytic residues; pink and green sticks, the substrate binding sites of CkOMT4 and CsOMT5, respectively. Predicted hydrogen bonds (cyan) and key interactions (orange) are indicated with dashed lines