Beta toxins bind at site-4 of sodium channels and shift the voltage of activation toward more negative potentials thereby affecting sodium channel activation and promoting spontaneous and repetitive firing. Has a selective effect toward Nav1.7/SCN9A which plays a role in pain mechanisms, and especially in the development of inflammatory pain. Shows no lethality toward mice. Expressed by the venom gland. Has the structural arrangement of an alpha-helix connected to antiparallel beta-sheets by disulfide bonds (CS-alpha/beta). The protein sequence seems to be related to the alpha-toxins, however experimental data show that it has a clear beta-toxin activity. Belongs to the long (4 C-C) scorpion toxin superfamily. Sodium channel inhibitor family. Alpha subfamily.