Chemical and biological characterization of four new linear cationic alpha-helical peptides from the venoms of two solitary eumenine wasps

• Autor(a) principal: Rangel, Marisa
• Data de Publicação: 2011
• Outros Autores: Santos Cabrera, Marcia Perez dos, Kazuma, Kohei, Ando, Kenji, Wang, Xiaoyu, Kato, Manabu, Nihei, Ken-ichi, Hirata, Izaura Yoshico [UNIFESP], Cross, Tyra J., Garcia, Angelica Nunes, Faquim-Mauro, Eliana L., Franzolin, Marcia Regina, Fuchino, Hiroyuki, Mori-Yasumoto, Kanami, Sekita, Setsuko, Kadowaki, Makoto, Satake, Motoyoshi, Konno, Katsuhiro
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://dx.doi.org/10.1016/j.toxicon.2011.04.014; http://repositorio.unifesp.br/handle/11600/33720
• topic: Solitary wasp; Linear cationic alpha-helical peptide; Amphipathic alpha-helix structure; Antimicrobial activity

Four novel peptides were isolated from the venoms of the solitary eumenine wasps Eumenes rubrofemoratus and Eumenes fraterculus. Their sequences were determined by MALDI-TOF/TOF (matrix assisted laser desorption/ionization time-of-flight mass spectrometry) analysis, Edman degradation and solid-phase synthesis. Two of them, eumenitin-R (LNLKGLIKKVASLLN) and eumenitin-F (LNLKGLFKKVASLLT), are highly homologous to eumenitin, an antimicrobial peptide from a solitary eumenine wasp, whereas the other two, EMP-ER (FDIMGLIKKVAGAL-NH(2)) and EMP-EF (FDVMGIIKKIAGAL-NH(2)), are similar to eumenine mastoparan-AF (EMP-AF), a mast cell degranulating peptide from a solitary eumenine wasp. These sequences have the characteristic features of linear cationic cytolytic peptides; rich in hydrophobic and basic amino acids with no disulfide bond, and accordingly, they can be predicted to adopt an amphipathic alpha-helix secondary structure. in fact, the CD (circular dichroism) spectra of these peptides showed significant alpha-helical conformation content in the presence of TFE (trifluoroethanol), SDS (sodium dodecylsulfate) and asolectin vesicles. in the biological evaluation, all the peptides exhibited a significant broad-spectrum antimicrobial activity, and moderate mast cell degranulation and leishmanicidal activities, but showed virtually no hemolytic activity. (C) 2011 Elsevier B.V. All rights reserved.