Guanidino groups greatly enhance the action of antimicrobial peptidomimetics against bacterial cytoplasmic membranes.

Konstantin Andreev, Christopher Bianchi, Jonas Striegler Laursen, Linda Citterio, Line Hein-Kristensen, Lone Gram, Ivan Kuzmenko, Christian Adam Olsen, David Gidalevitz

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Antimicrobial peptides or their synthetic mimics are a promising class of potential new antibiotics. Herein we assess the effect of the type of cationic side chain (i.e., guanidino vs. amino groups) on the membrane perturbing mechanism of antimicrobial α-peptide-β-peptoid chimeras. Langmuir monolayers composed of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylglycerol (DPPG) were used to model cytoplasmic membranes of both Gram-positive and Gram-negative bacteria, while lipopolysaccharide Kdo2-lipid A monolayers were mimicking the outer membrane of Gram-negative species. We report the results of the measurements using an array of techniques, including high-resolution synchrotron surface X-ray scattering, epifluorescence microscopy, and in vitro antimicrobial activity to study the molecular mechanisms of peptidomimetic interaction with bacterial membranes. We found guanidino group-containing chimeras to exhibit greater disruptive activity on DPPG monolayers than the amino group-containing analogues. However, this effect was not observed for lipopolysaccharide monolayers where the difference was negligible. Furthermore, the addition of the nitrobenzoxadiazole fluorophore did not reduce the insertion activity of these antimicrobials into both model membrane systems examined, which may be useful for future cellular localization studies.
Original languageEnglish
JournalBBA Biomembranes
Volume1838
Issue number10
Pages (from-to)2492-2502
Number of pages11
ISSN0005-2736
DOIs
Publication statusPublished - 2014

Keywords

  • GUANIDINES
  • Antimicrobial peptidomimetics
  • Peptide–peptoid chimeras
  • Guanidinium cation
  • Bacterial membrane
  • Phosphatidylglycerol
  • X-ray scattering

Cite this

Andreev, K., Bianchi, C., Laursen, J. S., Citterio, L., Hein-Kristensen, L., Gram, L., Kuzmenko, I., Olsen, C. A., & Gidalevitz, D. (2014). Guanidino groups greatly enhance the action of antimicrobial peptidomimetics against bacterial cytoplasmic membranes. BBA Biomembranes, 1838(10), 2492-2502. https://doi.org/10.1016/j.bbamem.2014.05.022