May function as a voltage-gated potassium channel blocker and may have cytolytic activity (Ref.3). However, it is noteworthy that the toxin often disappears from the venom fractions tested. Hence, the toxin may be frequently processed in the venom, which justifies the absence of Ts19 Frag-I among different venom samples (PubMed:26116782). Specific and reversible blocker of Kv1.2/KCNA2 (IC(50)=544 nM). Shows cytolytic effects on erythrocytes. In addition, induces non-selective pores formation when high concentrations (300 nM) are applied on oocytes. Expressed by the venom gland. Does not show inhibiting activities on most potassium channels tested and on all sodium channels tested. Here is the list of all channels that are not inhibited by the toxin: Kv1.1/KCNA1, Kv1.3/KCNA3, Kv1.4/KCNA4, Kv1.5/KCNA5, Kv1.6/KCNA6, Kv2.1/KCNB1, Kv3.1/KCNC1, Kv4.2/KCND2, Kv7.1/KCNQ1, Kv7.2/KCNQ2, Kv7.4/KCNQ4, Kv7.5/KCNA5, Kv10.1/KCNH1/EAG1, Kv11.1/KCNH2/ERG1, Shaker/Sh, Nav1.2/SCN2A, Nav1.4/SCN4A, Nav1.5/SCN5A, Nav1.6/SCN8A, and B.germanica Nav. Does not show blocking effet on Kv1.2/KCNA2 potassium channels. The fragments 26-37, 34-42 and 43-52 described in PubMed:18718845 correspond to the propeptide and some additional residues of the chain. The authors do not know if these fragments are the result of the post-translational maturation process, or if they have a biological activity of their own. Belongs to the long chain scorpion toxin family. Class 2 subfamily.