Characterization of the first K+ channel blockers from the venom of the Moroccan scorpion Buthus occitanus Paris

► We characterized 3 novel peptides from the Buthus occitanus Paris scorpion venom. ► BoPKTX behaves as the Kv1.3 channel blocker KTX and is designated α-KTx3.17. ► BoP1 and BoP2 relate to the Martentoxin and thus belong to the α-KTx16 family.