Peptoids successfully inhibit the growth of gram negative E-coli causing substantial membrane damage

Biljana Mojsoska, Gustavo Carretero, Sylvester Larsen, Ramona Valentina Mateiu, Havard Jenssen

    Research output: Contribution to journalJournal articleResearchpeer-review

    330 Downloads (Pure)

    Abstract

    Peptoids are an alternative approach to antimicrobial peptides that offer higher stability towards enzymatic degradation. It is essential when developing new types of peptoids, that mimic the function of antimicrobial peptides, to understand their mechanism of action. Few studies on the specific mechanism of action of antimicrobial peptoids have been described in the literature, despite the plethora of studies on the mode of action of antimicrobial peptides. Here, we investigate the mechanism of action of two short cationic peptoids, rich in lysine and tryptophan side chain functionalities. We demonstrate that both peptoids are able to cause loss of viability in E. coli susceptible cells at their MIC (16-32 mu g/ml) concentrations. Dye leakage assays demonstrate slow and low membrane permeabilization for peptoid 1, that is still higher for lipid compositions mimicking bacterial membranes than lipid compositions containing Cholesterol. At concentrations of 4 x MIC (64-128 mu g/ml), pore formation, leakage of cytoplasmic content and filamentation were the most commonly observed morphological changes seen by SEM in E. coli treated with both peptoids. Flow cytometry data supports the increase of cell size as observed in the quantification analysis from the SEM images and suggests overall decrease of DNA per cell mass over time.
    Original languageEnglish
    Article number42332
    JournalScientific Reports
    Volume7
    Number of pages12
    ISSN2045-2322
    DOIs
    Publication statusPublished - 2017

    Fingerprint Dive into the research topics of 'Peptoids successfully inhibit the growth of gram negative E-coli causing substantial membrane damage'. Together they form a unique fingerprint.

    Cite this