Antibacterial and leishmanicidal activities of temporin-SHd, a 17-residue long membrane-damaging peptide Abbassi, F. Raja, Z. /Oury, Bruno /Gazanion, Elodie Piesse, C. /Sereno, Denis Nicolas, P. Foulon, T. Ladram, A. Antimicrobial peptide Amphibian Temporin-SH Circular dichroism Membrane interaction/permeabilization Antiparasitic activity Temporins are a family of short antimicrobial peptides (8-17 residues) that mostly show potent activity against Gram-positive bacteria. Herein, we demonstrate that temporin-SHd, a 17-residue peptide with a net charge of +2 (FLPAALAGIGGILGKLF(amide)) expressed a broad spectrum of antimicrobial activity. This peptide displayed potent antibacterial activities against Gram-negative and Gram-positive bacteria, including multi-drug resistant Staphylococcus aureus strains, as well as antiparasitic activity against promastigote and the intracellular stage (amastigote) of Leishmania infantum, at concentration not toxic for the macrophages. Temporin-SHd that is structured in a non-amphipathic alpha-helix in anionic membrane-mimetic environments, strongly and selectively perturbs anionic bilayer membranes by interacting with the polar head groups and acyl region of the phospholipids, with formation of regions of two coexisting phases: one phase rich in peptide and the other lipid-rich. The disruption of lipid packing within the bilayer may lead to the formation of transient pores and membrane permeation/disruption once a threshold peptide accumulation is reached. To our knowledge, Temporin-SHd represents the first known 17-residue long temporin expressing such broad spectrum of antimicrobial activity including members of the trypanosomatidae family. Additionally, since only a few shorter members (13 residues) of the temporin family are known to display antileishmanial activity (temporins-TA, -TB and -SHa), SHd is an interesting tool to analyze the antiparasitic mechanism of action of temporins. 2013 text https://www.documentation.ird.fr/hor/fdi:010060735 fdi:010060735 Abbassi F., Raja Z., Oury Bruno, Gazanion Elodie, Piesse C., Sereno Denis, Nicolas P., Foulon T., Ladram A.. Antibacterial and leishmanicidal activities of temporin-SHd, a 17-residue long membrane-damaging peptide. 2013, 95 (2), 388-399 EN