Antimicrobial Peptides from Skin Secretions of Hypsiboas pulchellus (Anura: Hylidae).

SIANO A.; HÚMPOLA M.V; DE OLIVEIRA E.; ALBERICIO F.; SIMONETTA A.C.; LAJMANOVICH R; TONARELLI G.G

JOURNAL OF NATURAL PRODUCTS

AMER CHEMICAL SOC

Lugar: Washington; Año: 2014 p. 831 - 841

0163-3864

The skin of many amphibians produces a large repertoire of antimicrobialpeptides that are crucial in the first line of defense against microbial invasion. Despite theimmense richness of wild amphibians in Argentina, knowledge about peptides withantimicrobial properties is limited to a few species. Here we used LC-MS-MS to analyzesamples of Hypsiboas pulchellus skin with the aim to identify antimicrobial peptides in the massrange of 1000 to 2000 Da. Twenty-three novel sequences were identified by MS, three ofwhich were selected for chemical synthesis and further studies. The three synthetic peptides,named P1-Hp-1971, P2-Hp-1935, and P3-Hp-1891, inhibited the growth of two ATCCstrains: Escherichia coli (MIC: 16, 33, and 17 μM, respectively) and Staphylococcus aureus(MIC: 8, 66, and 17 μM, respectively). P1-Hp-1971 and P3-Hp-1891 were the most activepeptides. P1-Hp-1971, which showed the highest therapeutic indices (40 for E. coli and 80 forS. aureus), is a proline-glycine-rich peptide with a highly unordered structure, while P3-Hp-1891 adopts an amphipathic α-helical structure in the presence of 2,2,2-trifluoroethanol andanionic liposomes. This is the first peptidomic study of Hypsiboas pulchellus skin secretions toallow the identification of antimicrobial peptides.