Thaulin-1: The first antimicrobial peptide isolated from the skin of a Patagonian frog Pleurodema thaul (Anura: Leptodactylidae: Leiuperinae) with activity against Escherichia coli

• Autor(a) principal: Marani, Mariela M.
• Data de Publicação: 2017
• Outros Autores: Perez, Luis O., de Araujo, Alyne Rodrigues, Plácido, Alexandra, Sousa, Carla F., Quelemes, Patrick Veras, Oliveira, Mayara, Gomes-Alves, Ana G., Pueta, Mariana, Gameiro, Paula, Tomás, Ana M., Delerue-Matos, Cristina, Eaton, Peter, Camperi, Silvia A., Basso, Néstor G., Leite, José Roberto de Souza de Almeida
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.22/13812
• topic: Amino Acid Sequence; Amphibian Proteins; Animals; Antimicrobial Cationic Peptides; Anura; Base Sequence; Cell Survival; DNA, Complementary; Erythrocytes; Escherichia coli; Gene Expression; Klebsiella pneumoniae; Macrophages; Mice; Mice, Inbred BALB C; Microbial Sensitivity Tests; Models, Molecular; Protein Structure, Secondary; Sequence Alignment; Skin; Solid-Phase Synthesis Techniques; Staphylococcus aureus

Patagonia's biodiversity has been explored from many points of view, however, skin secretions of native amphibians have not been evaluated for antimicrobial peptide research until now. In this sense, Pleurodema thaul is the first amphibian specie to be studied from this large region of South America. Analysis of cDNA-encoding peptide in skin samples allowed identification of four new antimicrobial peptides. The predicted mature peptides were synthesized and all of them showed weak or null antimicrobial activity against Klebsiella pneumoniae, Staphylococcus aureus and Escherichia coli with the exception of thaulin-1, a cationic 26-residue linear, amphipathic, Gly- and Leu-rich peptide with moderate antimicrobial activity against E. coli (MIC of 24.7μM). AFM and SPR studies suggested a preferential interaction between these peptides and bacterial membranes. Cytotoxicity assays showed that thaulin peptides had minimal effects at MIC concentrations towards human and animal cells. These are the first peptides described for amphibians of the Pleurodema genus. These findings highlight the potential of the Patagonian region's unexplored biodiversity as a source for new molecule discovery.