Structure and membrane interactions of the homodimeric antibiotic peptide homotarsinin

• DOI: 10.1038/srep40854
• Publication Date: 2017-01-19T14:10:29Z
• Authors: Rodrigo M. Verly; Jarbas M. Resende; Eduardo F. C. Junior; Mariana T. Q. de ...; Carlos F. C. R. G...; Victor H. O. Munhoz; Marcelo Porto Bem...; Fábio C. L. Almeida; Marcelo M. Santoro; Dorila Piló-Veloso; Burkhard Bechinger
• Keywords: 0301 basic medicine; Circular Dichroism; Lipid Bilayers; Microbial Sensitivity Tests; Calorimetry; Gram-Positive Bacteria; Article; Dynamic Light Scattering; Protein Structure, Tertiary; 03 medical and health sciences; Gram-Negative Bacteria; Animals; Amino Acid Sequence; Anura; Dimerization; Nuclear Magnetic Resonance, Biomolecular; Antimicrobial Cationic Peptides

Abstract Antimicrobial peptides (AMPs) from amphibian skin are valuable template structures to find new treatments against bacterial infections. This work describes for the first time structure and membrane interactions of a homodimeric AMP. Homotarsinin, which was found in Phyllomedusa tarsius anurans, consists two identical cystine-linked polypeptide chains each 24 amino acid residues. The high-resolution monomeric dimeric were determined aqueous buffers. dimer exhibits tightly packed coiled coil three-dimensional structure, keeping hydrophobic residues screened environment. An overall cationic surface assures enhanced with negatively charged membranes. extensive set biophysical data allowed us establish structure-function correlations antimicrobial assays Gram -positive -negative bacteria. Although both present considerable activity, is significantly more effective antibacterial assays.