Mechanisms of bacterial membrane permeabilization by crotalicidin (Ctn) and its fragment Ctn(15–34), antimicrobial peptides from rattlesnake venom

Fire blight is a major pome fruit trees disease that is caused by the quarantine phytopathogenic Erwinia amylovora, leading to major losses, namely, in pear and apple productions. Nevertheless, no effective sustainable control treatments and measures have yet been disclosed. In that regard, antimicrobial peptides (AMPs) have been proposed as an alternative biomolecule against pathogens but some of those AMPs have yet to be tested against E. amylovora. In this study, the potential of five AMPs (RW-BP100, CA-M, 3.1, D4E1, and Dhvar-5) together with BP100, were assessed to control E. amylovora. Antibiograms, minimal inhibitory, and bactericidal concentrations (minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC), growth and IC50 were determined and membrane permeabilization capacity was evaluated by flow cytometry analysis and colony-forming units (CFUs) plate counting. For the tested AMPs, the higher inhibitory and bactericidal capacity was observed for RW-BP100 and CA-M (5 and 5–8 µM, respectively for both MIC and MBC), whilst for IC50 RW-BP100 presented higher efficiency (2.8 to 3.5 µM). Growth curves for the first concentrations bellow MIC showed that these AMPs delayed E. amylovora growth. Flow cytometry disclosed faster membrane permeabilization for CA-M. These results highlight the potential of RW-BP100 and CA-M AMPs as sustainable control measures against E. amylovora.

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A Rapid Fluorescence-Based Microplate Assay to Investigate the Interaction of Membrane Active Antimicrobial Peptides with Whole Gram-Positive Bacteria

Antibiotics ◽

10.3390/antibiotics9020092 ◽

2020 ◽

Vol 9 (2) ◽

pp. 92 ◽

Cited By ~ 2

Author(s):

Gerard Boix-Lemonche ◽

Maria Lekka ◽

Barbara Skerlavaj

Keyword(s):

Antimicrobial Peptides ◽

Staphylococcus Epidermidis ◽

Membrane Depolarization ◽

Membrane Permeabilization ◽

Microplate Assay ◽

Membrane Systems ◽

Gram Positive Bacteria ◽

Gramicidin D ◽

Membrane Effects ◽

Specific Membrane

Background: Membrane-active antimicrobial peptides (AMPs) are interesting candidates for the development of novel antimicrobials. Although their effects were extensively investigated in model membrane systems, interactions of AMPs with living microbial membranes are less known due to their complexity. The aim of the present study was to develop a rapid fluorescence-based microplate assay to analyze the membrane effects of AMPs in whole Staphylococcus aureus and Staphylococcus epidermidis. Methods: Bacteria were exposed to bactericidal and sub-inhibitory concentrations of two membrane-active AMPs in the presence of the potential-sensitive dye 3,3′-dipropylthiadicarbocyanine iodide (diSC3(5)) and the DNA staining dye propidium iodide (PI), to simultaneously monitor and possibly distinguish membrane depolarization and membrane permeabilization. Results: The ion channel-forming gramicidin D induced a rapid increase of diSC3(5), but not PI fluorescence, with slower kinetics at descending peptide concentrations, confirming killing due to membrane depolarization. The pore-forming melittin, at sub-MIC and bactericidal concentrations, caused, respectively, an increase of PI fluorescence in one or both dyes simultaneously, suggesting membrane permeabilization as a key event. Conclusions: This assay allowed the distinction between specific membrane effects, and it could be applied in the mode of action studies as well as in the screening of novel membrane-active AMPs.

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Comparing Bacterial Membrane Interactions of Antimicrobial Peptides and Their Mimics

Methods in Molecular Biology - Antimicrobial Peptides ◽

10.1007/978-1-60761-594-1_12 ◽

2009 ◽

pp. 171-182 ◽

Cited By ~ 26

Author(s):

Nathaniel P. Chongsiriwatana ◽

Annelise E. Barron

Keyword(s):

Antimicrobial Peptides ◽

Bacterial Membrane ◽

Membrane Interactions

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Study of the Affinity of Structurally Different Antimicrobial Peptides to Model Membranes and Their Ability to Induce Membrane Permeabilization

Biophysical Journal ◽

10.1016/j.bpj.2011.11.516 ◽

2012 ◽

Vol 102 (3) ◽

pp. 91a

Author(s):

Katia Regina Perez ◽

Bruno Mattei ◽

Tatiana M. Domingues ◽

Antonio Miranda ◽

Karin A. Riske

Keyword(s):

Antimicrobial Peptides ◽

Membrane Permeabilization ◽

Model Membranes

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Structural characterization of the antimicrobial peptides myxinidin and WMR in bacterial membrane mimetic micelles and bicelles

10.1101/2021.03.30.437760 ◽

2021 ◽

Author(s):

Yevhen K. Cherniavskyi ◽

Rosario Oliva ◽

Marco Stellato ◽

Pompea Del Vecchio ◽

Stefania Galdiero ◽

...

Keyword(s):

Molecular Dynamics ◽

Antimicrobial Peptides ◽

Molecular Dynamics Simulations ◽

Lipid Bilayers ◽

Structural Characterization ◽

Bacterial Membrane ◽

Membrane Composition ◽

Membrane Mimetic ◽

Dynamics Simulations

Antimicrobial peptides are a promising class of alternative antibiotics that interact selectively with negatively charged lipid bilayers. This paper presents the structural characterization of the antimicrobial peptides myxinidin and WMR associated with bacterial membrane mimetic micelles and bicelles by NMR, CD spectroscopy, and Molecular Dynamics simulations. Both peptides adopt a different conformation in the lipidic environment than in aqueous solution. The location of peptides in micelles and bicelles has been studied by paramagnetic relaxation enhancement experiments with paramagnetic tagged 5- and 16-doxyl stearic acid (5-/16-SASL). Multi-microsecond long molecular dynamics simulations of multiple copies of the peptides were used to gain an atomic level of detail on membrane-peptide and peptide-peptide interactions. Our results highlight an essential role of the negatively charged membrane mimetic in the structural stability of both myxinidin and WMR. The peptides localize predominantly in the membrane's headgroup region and have a noticeable membrane thinning effect on the overall bilayer structure. Myxinidin and WMR show different tendency to self-aggregate, which is also influenced by the membrane composition (DOPE/DOPG versus DOPE/DOPG/CL) and can be related to the previously observed difference in the ability of the peptides to disrupt different types of model membranes.

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Characterization and Antimicrobial Activity of Amphiphilic Peptide AP3 and Derivative Sequences

Antibiotics ◽

10.3390/antibiotics8010020 ◽

2019 ◽

Vol 8 (1) ◽

pp. 20 ◽

Cited By ~ 4

Author(s):

Christina Chrom ◽

Lindsay Renn ◽

Gregory Caputo

Keyword(s):

Antimicrobial Activity ◽

Fluorescence Spectroscopy ◽

Lipid Bilayers ◽

Lipid Membranes ◽

Cd Spectroscopy ◽

Membrane Permeabilization ◽

Bacterial Membrane ◽

Bacterial Strains ◽

Bacterial Membranes ◽

Model Lipid Membranes

The continued emergence of new antibiotic resistant bacterial strains has resulted in great interest in the development of new antimicrobial treatments. Antimicrobial peptides (AMPs) are one of many potential classes of molecules to help meet this emerging need. AMPs are naturally derived sequences, which act as part of the innate immune system of organisms ranging from insects through humans. We investigated the antimicrobial peptide AP3, which is originally isolated from the winter flounder Pleuronectes americanus. This peptide is of specific interest because it does not exhibit the canonical facially amphiphilic orientation of side chains when in a helical orientation. Different analogs of AP3 were synthesized in which length, charge identity, and Trp position were varied to investigate the sequence-structure and activity relationship. We performed biophysical and microbiological characterization using fluorescence spectroscopy, CD spectroscopy, vesicle leakage assays, bacterial membrane permeabilization assays, and minimal inhibitory concentration (MIC) assays. Fluorescence spectroscopy showed that the peptides bind to lipid bilayers to similar extents, while CD spectra show the peptides adopt helical conformations. All five peptides tested in this study exhibited binding to model lipid membranes, while the truncated peptides showed no measurable antimicrobial activity. The most active peptide proved to be the parent peptide AP3 with the highest degree of leakage and bacterial membrane permeabilization. Moreover, it was found that the ability to permeabilize model and bacterial membranes correlated most closely with the ability to predict antimicrobial activity.

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Antimicrobial peptides from chilli pepper seeds causes yeast plasma membrane permeabilization and inhibits the acidification of the medium by yeast cells

Biochimica et Biophysica Acta (BBA) - General Subjects ◽

10.1016/j.bbagen.2006.04.010 ◽

2006 ◽

Vol 1760 (9) ◽

pp. 1323-1332 ◽

Cited By ~ 56

Author(s):

Mariângela S.S. Diz ◽

André O. Carvalho ◽

Rosana Rodrigues ◽

Ana Gisele C. Neves-Ferreira ◽

Maura Da Cunha ◽

...

Keyword(s):

Plasma Membrane ◽

Antimicrobial Peptides ◽

Membrane Permeabilization ◽

Yeast Cells ◽

Chilli Pepper ◽

Yeast Plasma Membrane ◽

Plasma Membrane Permeabilization

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Adaptation of a bacterial membrane permeabilization assay for quantitative evaluation of benzalkonium chloride as a membrane-disrupting agent

MedChemComm ◽

10.1039/c7md00113d ◽

2017 ◽

Vol 8 (7) ◽

pp. 1408-1413 ◽

Cited By ~ 4

Author(s):

Julien Gravel ◽

Catherine Paradis-Bleau ◽

Andreea R. Schmitzer

Keyword(s):

Quantitative Evaluation ◽

Benzalkonium Chloride ◽

Membrane Permeabilization ◽

Bacterial Membrane ◽

Data Treatment

We describe the use of the ortho-nitrophenyl-β-galactoside (ONPG) assay developed by Lehrer et al. to which a new mathematical data treatment was applied.

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