2011 - Chemical and biological characterization of four new linear cationic a-helical peptides from the venoms of two solitary eumenine wasps
Port-a-Patch publication in Toxicon (2011)
Rangel M., dos Santos Cabrera M.P., Kazuma K., Ando K., Wang X., Kato M., Nihei K., HirataI.Y., Cross T.J., Garcia .N., Faquim-Mauro E.L., Franzolin M.R., Fuchino H., Mori-Yasumoto K., SekitaS., Kadowaki M., SatakeM., KonnoK.
Toxicon (2011) 57:1081-1092
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-NH2) and EMP-EF (FDVMGIIKKIAGAL-NH2), 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 α-helix secondary structure. In fact, the CD (circular dichroism) spectra of these peptides showed significant α-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.