Fig. 8.

Scorpion β-toxins. a Structures of representative anti-mammalian (Css4, homology model from [48]), anti-insect excitatory (Bj-xtrIT, PDB 1BCG), and anti-insect depressant (LqhIT2, PDB 2I61) scorpion β-toxins. Red denotes the primary pharmacophore located on the α-helix consisting of a central Glu flanked by two hydrophobic residues. Blue residues comprise the secondary pharmacophore. Glu15 in Bj-xtrIT and Css4, and Ala13 in LqhIT2 are colored yellow. b Primary structures of representative scorpion β-toxins