Structure and membrane interactions of the homodimeric antibiotic peptide homotarsinin.
Fiche publication
Date publication
janvier 2017
Journal
Scientific reports
Auteurs
Membres identifiés du Cancéropôle Est :
Pr BECHINGER Burkhard
Tous les auteurs :
Verly RM, Resende JM, Junior EF, de Magalhães MT, Guimarães CF, Munhoz VH, Bemquerer MP, Almeida FC, Santoro MM, Piló-Veloso D, Bechinger B
Lien Pubmed
Résumé
Antimicrobial peptides (AMPs) from amphibian skin are valuable template structures to find new treatments against bacterial infections. This work describes for the first time the structure and membrane interactions of a homodimeric AMP. Homotarsinin, which was found in Phyllomedusa tarsius anurans, consists of two identical cystine-linked polypeptide chains each of 24 amino acid residues. The high-resolution structures of the monomeric and dimeric peptides were determined in aqueous buffers. The dimer exhibits a tightly packed coiled coil three-dimensional structure, keeping the hydrophobic residues screened from the aqueous environment. An overall cationic surface of the dimer assures enhanced interactions with negatively charged membranes. An extensive set of biophysical data allowed us to establish structure-function correlations with antimicrobial assays against Gram-positive and Gram-negative bacteria. Although both peptides present considerable antimicrobial activity, the dimer is significantly more effective in both antibacterial and membrane biophysical assays.
Référence
Sci Rep. 2017 Jan;7:40854