This family consists of acidic alpha-KTx short chain scorpion toxins. These toxins named parabutoxins, block voltage-gated K channels and have extremely low pI values. Furthermore, they lack the crucial pore-plugging lysine. In addition, the second important residue of the dyad, the hydrophobic residue (Phe or Tyr) is also missing.
Jiyao W et al.(2023). "The conserved domain database in 2023.",