Figure 5. Transparent surface representation of the substrate-binding regions of (A) BthTx-I and (B) human group II secreted PLA₂ (PDB code 1BBC; [35]), showing the active-site (positions 48, 49, 52 and 99) and substrate-binding residues (positions 5, 22, 102 and 106) for both proteins.

The solvent-accessible surface is shown, and the dark grey area in each Figure corresponds to the exposed surfaces of the side chains at positions 5, 102 and 106. The Figure was prepared using SwissPDB software [39].