Figure 1.

Crystal structure of SmChiB in complex with berberine. (A) Structure of berberine. The conjugate tetracycle plane is shown in green-cyan, the 9-O-methoxy and 10-O-methoxy moieties are shown in pink. (B) Binding mode of berberine in the active pocket of SmChiB. Berberine is shown in stick representation with carbon atoms in green. The aromatic residues that stack with berberine are labelled and shown in stick representation with carbon atoms in yellow. The amino residues forming the hydrophobic cavity extended near the +2 subsite are labelled and shown as stick representation with carbon atoms in blue. The numbers indicate the subsite to which the berberine is bound.