Fig. 3.

Crystal structure of apo Slt and of complexes with compounds 1p, 2p, 3p, and IIpa. (A) 3D structure of the apo Slt. The catalytic groove is located in the C-terminal domain (in brown) where the catalytic E503 (labeled) is located; the neighboring domains U (in orange) and L (in blue) close the annular structure around the central opening. Stereo images for the (B) Slt:2p complex, (C) Slt:1p complex, (D) Slt:3p complex, and (E) Slt:IIpa complex. Catalytic subsites are labeled, and all of the compounds are shown as capped sticks in green for the carbon atoms. Residues interacting with the ligand are also depicted as capped sticks.