Cinerascetins, new peptides from Hypsiboas cinerascens : MALDI LIFT-TOF-MS/MS de novo sequence and imaging analysis

• Autor(a) principal: Almeida, Richardson Alves de
• Data de Publicação: 2015
• Outros Autores: Gordo, Marcelo, Silva, Felipe Moura Araujo da, Araújo, Rafael C. de, Ramada, Marcelo Henrique Soller, Abrão, Fernando Yano, Costa, Túlio O. G., Koolen, Hector Henrique Ferreira, Souza, Afonso Duarte Leão de, Bloch Júnior, Carlos
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UnB
• Texto Completo: http://repositorio.unb.br/handle/10482/29693; http://dx.doi.org/10.5935/0103-5053.20150219
• topic: Anuro; Peptídeos antimicrobianos; Secreção cutânea

The continuous search for antimicrobial candidates pushes the pursuit of compounds in the most diverse organisms. Amphibians are known as a prolific source of antibacterial peptides. Based on the rich biodiversity of the Amazon region the unexplored green-tree frog (Hypsiboas cinerascens) was studied for its skin secretion peptide content. Chromatographic separations and established tandem mass spectrometry (MS/MS) methods were used for sequencing the primary structures of the purified compounds. De novo sequencing lead to the identification of five new peptides related to hylaseptin P1, displaying an aminated C-terminal. Sequencing of the complementary deoxyribonucleic acid (cDNA) analysis allowed the disambiguation of isobaric amino-acids for C-01. Matrix assisted laser desorption ionization (MALDI) was carried out, demonstrating the in situ co-occurrence of the identified peptides in the dorsal skin. The major peptide C-01 was synthesized and assayed against a selection of microorganisms displaying minimal inhibitory concentrations (MICs) ranging from 4 to 16 µM.