Synthetic melittin, the main component of the honeybee venom. The amphiphilic nature of this antimicrobial peptide makes it a excellent model compound for monitoring lipid-protein interactions in membranes.  Integrates into cell membranes and has multiple effects, probably, as a result of its interaction with negatively charged phospholipids. It inhibits well known transport pumps such as the Na(+)-K(+)-ATPase and the H(+)-K(+)-ATPase. Increases the permeability of cell membranes to ions, particularly Na+ and indirectly Ca(2+), because of the Na(+)-Ca(2+)-exchange.