“…β-Bungarotoxin (β-BTX) from Bungarus multicinctus (Class I, Basic) (Uniprot P00617), OS2 from Oxyuranus scutellatus (Class I, Basic) (Uniprot Q45Z47), Myotoxin II from Bothrops asper (Class II, Basic) (Uniprot P24605), APP-D49 from A. piscivorus (Class II, Basic) (Uniprot P51972), BpirPLA2-I from Bothrops pirajai (Class II, Acid) (Uniprot C9DPL5), Bothropstoxin-1 (BThTx-I) from Bothrops jararacussu (Class II, Basic) (Uniprot Q90249), and Crotoxin B from Crotalus durissus terrificus (Class II, Basic) (Uniprot P24027). Green: N-terminal region critical for enzymatic and neurotoxic properties, C-terminal region essential for enzymatic activity and central Histidine in the catalytic site (Rouault et al, 2006), Yellow: C-terminal region with myotoxic properties (Lomonte et al, 1994;Nunez et al, 2001), Dark green: C-terminal region with anti-platelet aggregation activity (Teixeira et al, 2011), Gray: Lysin residues involved in the nociceptive, and/or endematogenic properties (Zambelli et al, 2017a) and Cyan: modified residues in the Crotoxin B which lead to alterations in the enzymatic, toxic, and pharmacological properties (Soares et al, 2001). (B-E) Cartoon representation of the three-dimensional structure of (B) β-Bungarotoxin with the PLA2 domain in red and knutiz domain in green (PDB 1BUN), (C) MitTx1 and ASIC1a channel complex with PLA2 domain in red, knutiz domain in green and ASIC1a channel in blue (PDB 4NTY), (D) Crotoxin B (PDB 2QOG) and (E) BThrTx1 (PDB 3HZD).…”