Magainins are closely related 23 amino acid amphipathic cationic peptides with broad-spectrum antimicrobial activities, originally extracted from the skin of the African clawed frog Xenopus laevis. Magainins 1 and magainin 2 are closely related hemolytic peptides which inhibit growth of bacteria by permeabilizing the cell membranes without significant toxicity against mammalian cells. The main target of magainin 1 and 2 is thought to be the lipid matrix of the membranes. Both magainin 1 and 2 are also cytotoxic to cancer cells and exhibit inhibitory action toward herpes simplex virus 1 and 2
