a highly selective blocker of the high conductance Ca²⁺-activated K⁺ channel. Iberiotoxin appears to modulate ChTX binding by an allosteric mechanism.

37-amino acid peptide with 3 disulfide bridges. Synthetic , originally from Buthus tamulus scorpion venom.

• Molecular Weight : 4,230 Da.
  
  
• Solubility in : well in water and saline.
  
  
• Purity min. : 99 % (HPLC).
  
  
• Biological Activity : As a specific blocker of Ca²⁺-activated K⁺ channels, Iberiotoxin does not affect other types of voltage-dependent K⁺ channels which are sensitive to inhibition by Charybdotoxin. IIberiotoxin blocks Ca²⁺-activated K⁺ channels by binding to their external mouth, and this binding is tighter and with an equilibrium dissociation constant 10-fold lower than that of Charybdotoxin.
  
  
• CAS Reg. No. : 129203-60-7
  
  
• Bibliography :
  
  1. Galvez et al., "Purification and characterization of a unique, potent, peptidyl probe for the high conductance calcium-activated potassium channel from venom of the scorpion Buthus tamulus." J. Biol. Chem. (1990) 265(19):11083-11090
  2. Candia et al., "Mode of action of Iberiotoxin, a potent blocker of the large conductance Ca2+-activated K+ channel." Biophys. J. (1992). 63:583-590