Structure and function of cationic hylin bioactive peptides from the tree frog Boana pulchella in interaction with lipid membranes

SILVANA AGUILAR; ANDRÉS E. BRUNETTI; AISEL VALLE GARAY; LIEM CANET SANTOS; LUIS PEREZ; DANIEL MOREIRA; NATALIA CANCELARICH; EDER ALVES BARBOSA; NESTOR BASSO; SONIA MARIA DE FREITAS; JULIAN FAIVOVICH; GUILHERME BRAND; GABRIELA M. CABRERA; JOSÉ LEITE; MARIELA MARANI

PEPTIDES

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2023

0196-9781

Amphibians have a great diversity of bioactive peptides in their skin. The cDNA prepro-peptide sequencing allowed the identification of five novel mature peptides expressed in the skin of Boana pulchella, four with similar sequences to hylin peptides having a cationic amphipathic-helical structure. Whole mature peptides and some of their fragments were chemically-synthesized and tested against Gram-positive and Gram-negative bacterial strains. The mature peptide hylin-Pul3 was the most active, with a MIC= 14 µM against Staphylococcus aureus. Circular dichroism assays indicated that peptides are mostly unstructured in buffer solutions. Still, adding large unilamellar vesicles composed of dimyristoyl phosphatidylcholine and dimyristoylphosphatidylglycerol increased the α-helix content of novel hylins. These results demonstrate the strong influence of the environment on peptide conformation and highlight its significance while addressing the pharmacology of peptides and their biological function in frogs.