Figure 4.
Comparative modeling of Gly insertion pseudosubstrates at BoNT/A-LC active-site. Shown are models of wildtype SNAP25 (residues 194–204) (top), the corresponding SNAPI with single Gly insertion (middle) or with three Gly insertions (bottom) complexed at the active site of BoNT/A-LC, generated using MODELLER software and presented with Pymol software (see Methods). Also indicated are the side chains of selected residues: Q197, R198, K201 of SNAP25 (shown in blue) and E257, D370 of BoNT/A (shown in green). The active site Zn ions are shown as purple spheres. Gly insertions were not numbered. Images of models on the left in each panel were vertically rotated 90° to generate the corresponding images on the right.