Figure 5.

Substrate binding of SalR. A, Ribbon diagrams showing the tertiary structure of SalR indicating the position of the substrate binding side. Residues shown in B are highlighted in blue. B, Close-up view of salutaridine binding site. The colors for the C-skeleton of each structure are green for salutaridine and gray for amino acids. Hydrogen, nitrogen, oxygen, and sulfur atoms are shown in white, blue, red, and yellow, respectively. Only interacting hydrogen atoms are shown. Interactions are indicated by dotted lines. C, Structure of salutaridine indicating carbon and ring numbering.