Antimicrobial activity of synthetic magainin peptides and several analogues.

We have previously reported the isolation of two broad-spectrum antimicrobial peptides ("magainins") from the skin of the African clawed frog Xenopus laevis. These natural peptides are active against many species of bacteria and fungi and also induce osmotic lysis of protozoa. In this report we demonstrate that synthetic magainin peptides appear to be indistinguishable from the natural products with respect to chromatographic properties and biological activity. These studies demonstrate conclusively that the magainin peptides are potent antimicrobial substances.