Novel antimicrobial peptides isolated from skin secretions of the Mexican frog Hyla eximia.

In this work, we describe the original characterization of peptides and proteins present in the skin secretions of the Mexican amphibian Hyla eximia. To this purpose, a novel water/dark extraction method, as well as the classic electrical stimulation procedure, was applied in order to extract the skin secretion. Two novel antimicrobial peptides He-1 and He-2 were sequenced. In addition, a molecular mass fingerprint revealed more than one hundred different molecules. Eight peptides in homogeneous form were assayed against five species of bacteria. Thereafter, the peptide He-2 demonstrated high antiparasitic activity against ookinete forms of malaria parasites at low concentration.