The Na+/K+ ATPase inhibitor Palytoxin acts by:
Palytoxin ranks among most potent non-protein toxins known, isolated from zoanthid corals Palythoa species, with LD50 subnanomolar due to profound effects on ion homeostasis. Target is Na+/K+ ATPase, P-type pump normally undergoing strict alternating access never simultaneously open both sides. Structural and electrophysiological studies show palytoxin binds extracellular entrance near ouabain site but wedges gates open, stabilizing conformation where intracellular gate formed by M5-M8 and extracellular gate formed by M1-M4 both unlatched, generating continuous pore approximately 13 angstrom d
Ref: Tosteson et al., Palytoxin Converts Na+/K+ ATPase into Non-Selective Ion Channel Mechanism.
