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Stephani J, Gerhards L, Khairalla B, Solov’yov IA, Brand I. How do Antimicrobial Peptides Interact with the Outer Membrane of Gram-Negative Bacteria? Role of Lipopolysaccharides in Peptide Binding, Anchoring, and Penetration. ACS Infect Dis 2024; 10:763-778. [PMID: 38259029 PMCID: PMC10862549 DOI: 10.1021/acsinfecdis.3c00673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 12/31/2023] [Accepted: 01/02/2024] [Indexed: 01/24/2024]
Abstract
Gram-negative bacteria possess a complex structural cell envelope that constitutes a barrier for antimicrobial peptides that neutralize the microbes by disrupting their cell membranes. Computational and experimental approaches were used to study a model outer membrane interaction with an antimicrobial peptide, melittin. The investigated membrane included di[3-deoxy-d-manno-octulosonyl]-lipid A (KLA) in the outer leaflet and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) in the inner leaflet. Molecular dynamics simulations revealed that the positively charged helical C-terminus of melittin anchors rapidly into the hydrophilic headgroup region of KLA, while the flexible N-terminus makes contacts with the phosphate groups of KLA, supporting melittin penetration into the boundary between the hydrophilic and hydrophobic regions of the lipids. Electrochemical techniques confirmed the binding of melittin to the model membrane. To probe the peptide conformation and orientation during interaction with the membrane, polarization modulation infrared reflection absorption spectroscopy was used. The measurements revealed conformational changes in the peptide, accompanied by reorientation and translocation of the peptide at the membrane surface. The study suggests that melittin insertion into the outer membrane affects its permeability and capacitance but does not disturb the membrane's bilayer structure, indicating a distinct mechanism of the peptide action on the outer membrane of Gram-negative bacteria.
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Affiliation(s)
- Justus
C. Stephani
- Institute
of Physics, Carl von Ossietzky University
of Oldenburg, 26111 Oldenburg, Germany
| | - Luca Gerhards
- Institute
of Physics, Carl von Ossietzky University
of Oldenburg, 26111 Oldenburg, Germany
| | - Bishoy Khairalla
- Department
of Chemistry, Carl von Ossietzky University
of Oldenburg, 26111 Oldenburg, Germany
| | - Ilia A. Solov’yov
- Institute
of Physics, Carl von Ossietzky University
of Oldenburg, 26111 Oldenburg, Germany
- Research
Center Neurosensory Science, Carl von Ossietzky
University of Oldenburg, 26111 Oldenburg, Germany
- CeNaD—Center
for Nanoscale Dynamics, Carl von Ossietzky
University of Oldenburg, 26111 Oldenburg, Germany
| | - Izabella Brand
- Department
of Chemistry, Carl von Ossietzky University
of Oldenburg, 26111 Oldenburg, Germany
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2
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Taguchi S, Okamoto Y, Suga K, Jung HS, Umakoshi H. Preparation of Planar Lipid Bilayer Membrane by Utilizing Bicelles and Its Characterization. KAGAKU KOGAKU RONBUN 2022. [DOI: 10.1252/kakoronbunshu.48.175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Shogo Taguchi
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo
| | - Yukihiro Okamoto
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University
| | - Keishi Suga
- Department of Chemical Engineering, Tohoku University
| | - Ho-Sup Jung
- Center for Food and Bioconvergence, Department of Food Science and Biotechnology, Seoul National University
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University
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3
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Chiou PC, Hsu WW, Chang Y, Chen YF. Molecular packing of lipid membranes and action mechanisms of membrane-active peptides. Colloids Surf B Biointerfaces 2022; 213:112384. [PMID: 35151994 DOI: 10.1016/j.colsurfb.2022.112384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 01/25/2022] [Accepted: 01/29/2022] [Indexed: 10/19/2022]
Abstract
Biomembranes are involved in diverse cellular activities. How membranes and proteins interact in the activities might hinge on the former's physical characteristics, which in turn are influenced by packing of lipid molecules. Yet, the validity of this understanding and its mechanism are unclear. By varying chain saturation of membranes, we explored correlations between lipid packing and peptide-mediated membrane disruption for the antimicrobial peptide, melittin, and amyloidogenic peptide, β-amyloid (1-42). Remarkably, reducing molecular packing flexibility enhanced the membrane disruption, possibly due to a shift from membrane perforation to micellization. A theoretical analysis suggested the energetic basis of this shift. This mechanistically shows that a peptide's mechanism might be dictated not only by its intrinsic properties but also by physical characteristics of membranes.
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Affiliation(s)
- Pin-Chiuan Chiou
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Wen-Wei Hsu
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Yung Chang
- R&D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan Christian University, Jhong-Li, Taoyuan 320, Taiwan
| | - Yi-Fan Chen
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan.
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4
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Insights into molecular mechanism of action of citrus flavonoids hesperidin and naringin on lipid bilayers using spectroscopic, calorimetric, microscopic and theoretical studies. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118411] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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5
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Labbé E, Buriez O. Electrode‐supported and free‐standing bilayer lipid membranes: Formation and uses in molecular electrochemistry. ELECTROCHEMICAL SCIENCE ADVANCES 2021. [DOI: 10.1002/elsa.202100170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Eric Labbé
- PASTEUR Département de Chimie Ecole Normale Supérieure PSL University Sorbonne Université CNRS Paris 75005 France
| | - Olivier Buriez
- PASTEUR Département de Chimie Ecole Normale Supérieure PSL University Sorbonne Université CNRS Paris 75005 France
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Brand I, Khairalla B. Structural changes in the model of the outer cell membrane of Gram-negative bacteria interacting with melittin: an in situ spectroelectrochemical study. Faraday Discuss 2021; 232:68-85. [PMID: 34542116 DOI: 10.1039/d0fd00039f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The cell membrane of Gram-negative bacteria interacting with an antimicrobial peptide presents a complex supramolecular assembly. Fabrication of models of bacterial cell membranes remains a large experimental challenge. Langmuir-Blodgett and Langmuir-Schaefer (LS-LB) transfer makes possible the deposition of multicomponent asymmetric lipid bilayers onto a gold surface. Two lipids: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) and di[3-deoxy-D-manno-octulosonyl]-lipid A (KLA) were used to deposit a model of the outer membrane of Gram-negative bacteria on the Au(111) substrate. The use of gold as the solid substrate enables control of the membrane potential. Molecular scale changes in the model membrane exposed to physiological electric fields and interacting with melittin antimicrobial peptide are discussed in this paper. The interaction of the outer membrane with melittin leads to an increase in the membrane capacitance and permeability to ions and water. The stability of the outer membrane with bound melittin decreases at positive membrane potentials. In situ polarization modulation infrared reflection absorption spectroscopy is used to investigate membrane potential-dependent changes in the structure of the outer membrane interacting with melittin. The hydration of the ester carbonyl groups is not affected by the interaction with melittin. However, the orientation and hydrogen bond network with the carboxylate groups in KLA changes drastically after POPE-KLA bilayer interacts with melittin. We propose that the positively charged groups in the amino acids present at the C-terminus of the peptide interact directly with the polar head group of KLA. Simultaneously, the packing order in hydrocarbon chains in the membrane with bound melittin increases. A hydrophobic match between the chains in the lipids and the peptide, which spans the membrane, seems to be responsible for the ordering of the hydrocarbon chains region of the bilayer. The N-terminus enters into the hydrophobic region of the membrane and forms a channel to the hydrophilic head groups in POPE.
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Affiliation(s)
- Izabella Brand
- Department of Chemistry, University of Oldenburg, 26111 Oldenburg, Germany.
| | - Bishoy Khairalla
- Department of Chemistry, University of Oldenburg, 26111 Oldenburg, Germany.
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7
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Swana KW, Nagarajan R, Camesano TA. Atomic Force Microscopy to Characterize Antimicrobial Peptide-Induced Defects in Model Supported Lipid Bilayers. Microorganisms 2021; 9:microorganisms9091975. [PMID: 34576869 PMCID: PMC8465339 DOI: 10.3390/microorganisms9091975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/07/2021] [Accepted: 09/13/2021] [Indexed: 11/16/2022] Open
Abstract
Antimicrobial peptides (AMPs) interact with bacterial cell membranes through a variety of mechanisms, causing changes extending from nanopore formation to microscale membrane lysis, eventually leading to cell death. Several AMPs also disrupt mammalian cell membranes, despite their significantly different lipid composition and such collateral hemolytic damage hinders the potential therapeutic applicability of the AMP as an anti-microbial. Elucidating the mechanisms underlying the AMP-membrane interactions is challenging due to the variations in the chemical and structural features of the AMPs, the complex compositional variations of cell membranes and the inadequacy of any single experimental technique to comprehensively probe them. (1) Background: Atomic Force Microscopy (AFM) imaging can be used in combination with other techniques to help understand how AMPs alter the orientation and structural organization of the molecules within cell membranes exposed to AMPs. The structure, size, net charge, hydrophobicity and amphipathicity of the AMPs affect how they interact with cell membranes of differing lipid compositions. (2) Methods: Our study examined two different types of AMPs, a 20-amino acid, neutral, α-helical (amphipathic) peptide, alamethicin, and a 13-amino acid, non-α-helical cationic peptide, indolicidin (which intramolecularly folds, creating a hydrophobic core), for their interactions with supported lipid bilayers (SLBs). Robust SLB model membranes on quartz supports, incorporating predominantly anionic lipids representative of bacterial cells, are currently not available and remain to be developed. Therefore, the SLBs of zwitterionic egg phosphatidylcholine (PC), which represents the composition of a mammalian cell membrane, was utilized as the model membrane. This also allows for a comparison with the results obtained from the Quartz Crystal Microbalance with Dissipation (QCM-D) experiments conducted for these peptides interacting with the same zwitterionic SLBs. Further, in the case of alamethicin, because of its neutrality, the lipid charge may be less relevant for understanding its membrane interactions. (3) Results: Using AFM imaging and roughness analysis, we found that alamethicin produced large, unstable defects in the membrane at 5 µM concentrations, and completely removed the bilayer at 10 µM. Indolicidin produced smaller holes in the bilayer at 5 and 10 µM, although they were able to fill in over time. The root-mean-square (RMS) roughness values for the images showed that the surface roughness caused by visible defects peaked after peptide injection and gradually decreased over time. (4) Conclusions: AFM is useful for helping to uncover the dynamic interactions between different AMPs and cell membranes, which can facilitate the selection and design of more efficient AMPs for use in therapeutics and antimicrobial applications.
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Affiliation(s)
- Kathleen W. Swana
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA 01609, USA;
- U.S. Army Combat Capabilities Development Command Soldier Center, Natick, MA 01760, USA;
| | - Ramanathan Nagarajan
- U.S. Army Combat Capabilities Development Command Soldier Center, Natick, MA 01760, USA;
| | - Terri A. Camesano
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA 01609, USA;
- Correspondence:
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8
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Zaborowska M, Dziubak D, Matyszewska D, Sek S, Bilewicz R. Designing a Useful Lipid Raft Model Membrane for Electrochemical and Surface Analytical Studies. Molecules 2021; 26:5483. [PMID: 34576954 PMCID: PMC8467995 DOI: 10.3390/molecules26185483] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/02/2021] [Accepted: 09/03/2021] [Indexed: 12/04/2022] Open
Abstract
A model biomimetic system for the study of protein reconstitution or drug interactions should include lipid rafts in the mixed lipid monolayer, since they are usually the domains embedding membrane proteins and peptides. Four model lipid films composed of three components: 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), cholesterol (Chol) and sphingomyelin (SM) mixed in different molar ratios were proposed and investigated using surface pressure measurements and thermodynamic analysis of the monolayers at the air-water interface and imaged by Brewster angle microscopy. The ternary monolayers were transferred from the air-water onto the gold electrodes to form bilayer films and were studied for the first time by electrochemical methods: alternative current voltammetry and electrochemical impedance spectroscopy and imaged by atomic force microscopy. In excess of DOPC, the ternary systems remained too liquid for the raft region to be stable, while in the excess of cholesterol the layers were too solid. The layers with SM in excess lead to the formation of Chol:SM complexes but the amount of the fluid matrix was very low. The equimolar content of the three components lead to the formation of a stable and well-organized assembly with well-developed raft microdomains of larger thickness, surrounded by the more fluid part of the bilayer. The latter is proposed as a convenient raft model membrane for further physicochemical studies of interactions with drugs or pollutants or incorporation of membrane proteins.
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Affiliation(s)
| | - Damian Dziubak
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02089 Warsaw, Poland; (D.D.); (S.S.)
| | - Dorota Matyszewska
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02089 Warsaw, Poland; (D.D.); (S.S.)
| | - Slawomir Sek
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02089 Warsaw, Poland; (D.D.); (S.S.)
| | - Renata Bilewicz
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02093 Warsaw, Poland;
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9
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Majewska M, Khan F, Pieta IS, Wróblewska A, Szmigielski R, Pieta P. Toxicity of selected airborne nitrophenols on eukaryotic cell membrane models. CHEMOSPHERE 2021; 266:128996. [PMID: 33288286 DOI: 10.1016/j.chemosphere.2020.128996] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/26/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
Nitroaromatics belong to the group of toxic components of aerosol particles and atmospheric hydrometeors that enter the atmosphere through biomass burning and fuel combustion. In the present work, we report on the cytotoxic effects of a 2-, 3- and 4-nitrophenol mixture on a model eukaryotic-like cell membrane and compared it with in vitro cellular models BEAS-2B (immortalized bronchial epithelial cells) and A549 (cancerous alveolar epithelial cells). A selected model biomembrane comprised of DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine), DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) and POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) was studied. The electrochemical-based method, combined with atomic force microscopy (AFM) and phase-contrast microscopy imaging, allowed to get insights into the mechanism of cellular function disruption caused by airborne nitrophenols. The efficacy of the method is supported by the data obtained from in vitro experiments performed on cell models. The nitrophenol mixture exhibited cytotoxic effects at concentrations above 100 μg mL-1, as demonstrated by phase-contrast microscopy in real lung cell lines. Electrochemical impedance spectroscopy (EIS) revealed the formation of membrane defects at a nitrophenol concentration of 200 μg mL-1. AFM imaging confirmed the model membrane disintegration and phospholipids rearrangement in the presence of nitrophenols. These observations indicate that particle-bound nitrophenols induce substantial changes in cell membranes and make them more permeable to aerosol, resulting in major cellular damage in the lungs when inhaled. The study provides initial evidence of cellular membrane damage induced by three important nitrated phenols present in the environment.
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Affiliation(s)
- Marta Majewska
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Faria Khan
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Izabela S Pieta
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Aleksandra Wróblewska
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Rafal Szmigielski
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
| | - Piotr Pieta
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
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10
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Electrochemical Properties of Lipid Membranes Self-Assembled from Bicelles. MEMBRANES 2020; 11:membranes11010011. [PMID: 33374818 PMCID: PMC7824464 DOI: 10.3390/membranes11010011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/18/2020] [Accepted: 12/21/2020] [Indexed: 12/16/2022]
Abstract
Supported lipid membranes are widely used platforms which serve as simplified models of cell membranes. Among numerous methods used for preparation of planar lipid films, self-assembly of bicelles appears to be promising strategy. Therefore, in this paper we have examined the mechanism of formation and the electrochemical properties of lipid films deposited onto thioglucose-modified gold electrodes from bicellar mixtures. It was found that adsorption of the bicelles occurs by replacement of interfacial water and it leads to formation of a double bilayer structure on the electrode surface. The resulting lipid assembly contains numerous defects and pinholes which affect the permeability of the membrane for ions and water. Significant improvement in morphology and electrochemical characteristics is achieved upon freeze–thaw treatment of the deposited membrane. The lipid assembly is rearranged to single bilayer configuration with locally occurring patches of the second bilayer, and the number of pinholes is substantially decreased. Electrochemical characterization of the lipid membrane after freeze–thaw treatment demonstrated that its permeability for ions and water is significantly reduced, which was manifested by the relatively high value of the membrane resistance.
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11
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Electrochemical Biosensors Based on Membrane-Bound Enzymes in Biomimetic Configurations. SENSORS 2020; 20:s20123393. [PMID: 32560121 PMCID: PMC7349357 DOI: 10.3390/s20123393] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 06/12/2020] [Accepted: 06/14/2020] [Indexed: 02/07/2023]
Abstract
In nature, many enzymes are attached or inserted into the cell membrane, having hydrophobic subunits or lipid chains for this purpose. Their reconstitution on electrodes maintaining their natural structural characteristics allows for optimizing their electrocatalytic properties and stability. Different biomimetic strategies have been developed for modifying electrodes surfaces to accommodate membrane-bound enzymes, including the formation of self-assembled monolayers of hydrophobic compounds, lipid bilayers, or liposomes deposition. An overview of the different strategies used for the formation of biomimetic membranes, the reconstitution of membrane enzymes on electrodes, and their applications as biosensors is presented.
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12
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Flavonol clustering in model lipid membranes: DSC, AFM, force spectroscopy and MD simulations study. Colloids Surf B Biointerfaces 2020; 193:111147. [PMID: 32526654 DOI: 10.1016/j.colsurfb.2020.111147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/06/2020] [Accepted: 05/18/2020] [Indexed: 11/23/2022]
Abstract
We here report on flavonols (myricetin (MCE) and its glycoside myricitrin (MCI)) - 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) membrane interactions focusing on the effects of flavonol clustering on the membrane thermotropic and nanomechanical properties. Atomic force microscopy (AFM), force spectroscopy (FS) and differential scanning calorimetry (DSC) together with molecular dynamics (MD) simulations provided a consistent picture of flavonol - DMPC membrane interactions. DMPC membrane as a supported lipid bilayer preserved its integrity even at higher flavonol molar fraction x. When present at x = 0.1 - 0.3, MCE and MCI both slightly improve DMPC bilayer fluidity which is evidenced by the decrease in the main phase transition temperature Tm. MCE is found within the interior of the bilayer, while MCI incorporates in the head group-water interface region. AFM and FS confirmed clusters as protrusions with an average height of 0.012 μm and average diameters of 0.60 and 0.24 μm for MCE and MCI clusters, respectively. The average membrane thickness in DMPC fluid phase decreases for 7% at xMCE = 0.30, while only 4% at xMCI = 0.27. The induced membrane changes are dependent on the chemical and physical properties of inserted flavonols. The hypothesis regarding the tendency of flavonol to clustering in membranes by increasing flavonol molar fraction has been confirmed.
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13
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Pandidan S, Mechler A. Membrane morphology effects in quartz crystal microbalance characterization of antimicrobial peptide activity. Biophys Chem 2020; 262:106381. [PMID: 32361097 DOI: 10.1016/j.bpc.2020.106381] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 04/15/2020] [Accepted: 04/19/2020] [Indexed: 10/24/2022]
Abstract
The mechanism of action of membrane disrupting antimicrobial peptides (AMPs) and the basis of their specificity and selectivity to pathogens are often studied by using biomimetic model membranes. It is often assumed that all model membrane morphologies, e.g. liposomes, supported bilayers, tethered bilayers etc. are equivalent. In this work the validity of this assumption was assessed. Melittin was used as the reference AMP as it can disrupt both bacterial and mammalian-mimetic membranes. Quartz crystal microbalance (QCM) viscoelastic fingerprints show characteristic differences between the three model morphologies: single bilayer membranes, multilamellar membrane stacks and unilamellar liposomes. In the second and third case, initial trends show material removal instead of material addition as in the single bilayer case, consistent with dissolution of some bilayers, and bursting liposomes, respectively. The latter is accompanied by a characteristic drop in the dissipation signal as the liposomes collapse. The results also highlight an important limitation of the QCM method, the need for a well established reference system for qualitative analysis of the viscoelastic fingerprints, and thus the importance of using the right model system, i.e. single bilayer membrane, for studies of the mechanism of action of AMPs.
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Affiliation(s)
- Sara Pandidan
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Adam Mechler
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia.
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14
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Clifton LA, Campbell RA, Sebastiani F, Campos-Terán J, Gonzalez-Martinez JF, Björklund S, Sotres J, Cárdenas M. Design and use of model membranes to study biomolecular interactions using complementary surface-sensitive techniques. Adv Colloid Interface Sci 2020; 277:102118. [PMID: 32044469 DOI: 10.1016/j.cis.2020.102118] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/24/2020] [Accepted: 01/29/2020] [Indexed: 01/07/2023]
Abstract
Cellular membranes are complex structures and simplified analogues in the form of model membranes or biomembranes are used as platforms to understand fundamental properties of the membrane itself as well as interactions with various biomolecules such as drugs, peptides and proteins. Model membranes at the air-liquid and solid-liquid interfaces can be studied using a range of complementary surface-sensitive techniques to give a detailed picture of both the structure and physicochemical properties of the membrane and its resulting interactions. In this review, we will present the main planar model membranes used in the field to date with a focus on monolayers at the air-liquid interface, supported lipid bilayers at the solid-liquid interface and advanced membrane models such as tethered and floating membranes. We will then briefly present the principles as well as the main type of information on molecular interactions at model membranes accessible using a Langmuir trough, quartz crystal microbalance with dissipation monitoring, ellipsometry, atomic force microscopy, Brewster angle microscopy, Infrared spectroscopy, and neutron and X-ray reflectometry. A consistent example for following biomolecular interactions at model membranes is used across many of the techniques in terms of the well-studied antimicrobial peptide Melittin. The overall objective is to establish an understanding of the information accessible from each technique, their respective advantages and limitations, and their complementarity.
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Affiliation(s)
- Luke A Clifton
- ISIS Pulsed Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 OQX, United Kingdom
| | - Richard A Campbell
- Division of Pharmacy and Optometry, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Federica Sebastiani
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden
| | - José Campos-Terán
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Av. Vasco de Quiroga 4871, Col. Santa Fe, Delegación Cuajimalpa de Morelos, 05348, Mexico; Lund Institute of advanced Neutron and X-ray Science, Lund University, Scheelevägen 19, 223 70 Lund, Sweden
| | - Juan F Gonzalez-Martinez
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden
| | - Sebastian Björklund
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden
| | - Javier Sotres
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden
| | - Marité Cárdenas
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden.
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15
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Nangia S, Boyd KJ, May ER. Molecular dynamics study of membrane permeabilization by wild-type and mutant lytic peptides from the non-enveloped Flock House virus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1862:183102. [PMID: 31678020 DOI: 10.1016/j.bbamem.2019.183102] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/16/2019] [Accepted: 10/14/2019] [Indexed: 12/19/2022]
Abstract
Flock House virus (FHV) serves as a model system for understanding infection mechanisms utilized by non-enveloped viruses to transport across cellular membranes. During the infection cycle of FHV, a fundamental stage involves disruption of the endosomal membrane by membrane active peptides, following externalization of the peptides from the capsid interior. The FHV lytic agents are the 44 C-terminal amino acids residues of the capsid protein, which are auto-catalytically cleaved during the capsid maturation process. The cleaved peptides are termed γ peptides. In this study, we perform multi-scale molecular dynamics simulations including 40 μs all-atom molecular dynamics simulations to study the behavior of pre-inserted transmembrane lytic peptides at a high concentration in a neutral membrane. We study the dynamical organization among peptides to form oligomeric bundles in four systems including the wild-type γ peptide and three mutant forms; namely, a truncation mutant in which the 23 C-terminal residues are deleted (γ1), a construct where the 8 C-terminal residues of γ are fused to γ1 (Δ385-399 γ) and a single-point mutant (F402A γ), all of which have been experimentally shown to drastically affect infectivity and lytic activity compared to the wild-type γ. Our results shed light on the actions of varied forms of the FHV lytic peptide including membrane insertion, trans-membrane stability, peptide oligomerization, water permeation activity and dynamic pore formation. Findings from this study provide detailed structural information and rationale for the differences in lytic activity among variants of FHV γ.
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Affiliation(s)
- Shivangi Nangia
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, United States of America
| | - Kevin J Boyd
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, United States of America
| | - Eric R May
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, United States of America.
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16
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Diverse effect of cationic lipopeptide on negatively charged and neutral lipid bilayers supported on gold electrodes. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2018.12.139] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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17
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Corrales Chahar F, Díaz S, Ben Altabef A, Gervasi C, Alvarez P. Interactions of valproic acid with lipid membranes of 1,2-dimyristoyl-sn-glycero-3-phosphocholine. Chem Phys Lipids 2019; 218:125-135. [DOI: 10.1016/j.chemphyslip.2018.12.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/06/2018] [Accepted: 12/20/2018] [Indexed: 11/25/2022]
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18
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Puiggalí-Jou A, Pawlowski J, del Valle LJ, Michaux C, Perpète EA, Sek S, Alemán C. Properties of Omp2a-Based Supported Lipid Bilayers: Comparison with Polymeric Bioinspired Membranes. ACS OMEGA 2018; 3:9003-9019. [PMID: 31459033 PMCID: PMC6645002 DOI: 10.1021/acsomega.8b00913] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 07/19/2018] [Indexed: 05/31/2023]
Abstract
Omp2a β-barrel outer membrane protein has been reconstituted into supported lipid bilayers (SLBs) to compare the nanomechanical properties (elastic modulus, adhesion forces, and deformation) and functionality of the resulting bioinspired system with those of Omp2a-based polymeric nanomembranes (NMs). Protein reconstitution into lipid bilayers has been performed using different strategies, the most successful one consisting of a detergent-mediated process into preformed liposomes. The elastic modulus obtained for the lipid bilayer and Omp2a are ∼19 and 10.5 ± 1.7 MPa, respectively. Accordingly, the protein is softer than the lipid bilayer, whereas the latter exhibits less mechanical strength than polymeric NMs. Besides, the function of Omp2a in the SLB is similar to that observed for Omp2a-based polymeric NMs. Results open the door to hybrid bioinspired substrates based on the integration of Omp2a-proteoliposomes and nanoperforated polymeric freestanding NMs.
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Affiliation(s)
- Anna Puiggalí-Jou
- Departament
d’Enginyeria Química, EEBE, Universitat Politècnica de Catalunya, C/Eduard Maristany, 10-14, Ed. I2, 08019 Barcelona, Spain
- Barcelona
Research Center for Multiscale Science and Engineering, Universitat Politècnica de Catalunya, C/Eduard Maristany, 10-14, Ed. C, 08019 Barcelona, Spain
| | - Jan Pawlowski
- Biological
and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Zwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Luis J. del Valle
- Departament
d’Enginyeria Química, EEBE, Universitat Politècnica de Catalunya, C/Eduard Maristany, 10-14, Ed. I2, 08019 Barcelona, Spain
- Barcelona
Research Center for Multiscale Science and Engineering, Universitat Politècnica de Catalunya, C/Eduard Maristany, 10-14, Ed. C, 08019 Barcelona, Spain
| | - Catherine Michaux
- Laboratoire
de Chimie Physique des Biomolécules, University of Namur, Rue de Bruxelles, 61, 5000 Namur, Belgium
| | - Eric A. Perpète
- Laboratoire
de Chimie Physique des Biomolécules, University of Namur, Rue de Bruxelles, 61, 5000 Namur, Belgium
| | - Slawomir Sek
- Biological
and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Zwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Carlos Alemán
- Departament
d’Enginyeria Química, EEBE, Universitat Politècnica de Catalunya, C/Eduard Maristany, 10-14, Ed. I2, 08019 Barcelona, Spain
- Barcelona
Research Center for Multiscale Science and Engineering, Universitat Politècnica de Catalunya, C/Eduard Maristany, 10-14, Ed. C, 08019 Barcelona, Spain
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19
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Bi H, Wang X, Han X, Voïtchovsky K. Impact of Electric Fields on the Nanoscale Behavior of Lipid Monolayers at the Surface of Graphite in Solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:9561-9571. [PMID: 30028144 DOI: 10.1021/acs.langmuir.8b01631] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The nanoscale organization and dynamics of lipid molecules in self-assembled membranes is central to the biological function of cells and in the technological development of synthetic lipid structures as well as in devices such as biosensors. Here, we explore the nanoscale molecular arrangement and dynamics of lipids assembled in monolayers at the surface of highly ordered pyrolytic graphite (HOPG), in different ionic solutions, and under electrical potentials. Using a combination of atomic force microscopy and fluorescence recovery after photobleaching, we show that HOPG is able to support fully formed and fluid lipid membranes, but mesoscale order and corrugations can be observed depending on the type of the lipid considered (1,2-dioleoyl- sn-glycero-3-phosphocholine, 1,2-dioleoyl- sn-glycero-3-phospho-l-serine (DOPS), and 1,2-dioleoyl-3-trimethylammoniumpropane) and the ion present (Na+, Ca2+, Cl-). Interfacial solvation forces and ion-specific effects dominate over the electrostatic changes induced by moderate electric fields (±1.0 V vs Ag/AgCl reference electrode) with particularly marked effects in the presence of calcium, and for DOPS. Our results provide insights into the interplay between the molecular, ionic, and electrostatic interactions and the formation of dynamical ordered structures in fluid lipid membranes.
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Affiliation(s)
- Hongmei Bi
- College of Science , Heilongjiang Bayi Agricultural University , Daqing 163319 , China
| | - Xuejing Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering , Harbin Institute of Technology , Harbin 150001 , China
| | - Xiaojun Han
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering , Harbin Institute of Technology , Harbin 150001 , China
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20
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Tuning phospholipid bilayer permeability by flavonoid apigenin: Electrochemical and atomic force microscopy study. J Electroanal Chem (Lausanne) 2018. [DOI: 10.1016/j.jelechem.2018.03.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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21
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Juhaniewicz-Dębińska J, Tymecka D, Sęk S. Lipopeptide-induced changes in permeability of solid supported bilayers composed of bacterial membrane lipids. J Electroanal Chem (Lausanne) 2018. [DOI: 10.1016/j.jelechem.2017.12.065] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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22
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Bodescu MA, Rosenkötter F, Fritz J. Time lapse AFM on vesicle formation from mixed lipid bilayers induced by the membrane-active peptide melittin. SOFT MATTER 2017; 13:6845-6851. [PMID: 28829104 DOI: 10.1039/c7sm01095h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Melittin is a model system for the action of antimicrobial peptides which are potential candidates for novel antibiotics. We investigated the membrane lysis effect of melittin on phase-separated supported lipid bilayers (DOPC-DPPC) by atomic force microscopy. AFM images show that the peptide first forms defects at the interface between the two lipid phases and then degrades preferentially the liquid-phase DOPC-enriched domains. Vesicular structures of 10-20 nm radius were observed to form, suggesting a mixed carpet-toroidal model mechanism for the resolved action of melittin.
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Affiliation(s)
- M A Bodescu
- Jacobs University Bremen, Department of Physics & Earth Sciences, Campus Ring 1, 28759 Bremen, Germany.
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23
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Gao T, Gu S, Mu C, Zhang M, Yang J, Liu P, Li G. Electrochemical assay of lipid kinase activity facilitated by liposomes. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2017.08.190] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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24
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Konarzewska D, Juhaniewicz J, Güzeloğlu A, Sęk S. Characterization of planar biomimetic lipid films composed of phosphatidylethanolamines and phosphatidylglycerols from Escherichia coli. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:475-483. [DOI: 10.1016/j.bbamem.2017.01.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 01/03/2017] [Accepted: 01/05/2017] [Indexed: 01/27/2023]
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25
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Interaction of Cecropin B with Zwitterionic and Negatively Charged Lipid Bilayers Immobilized at Gold Electrode Surface. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.04.080] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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26
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Pan J, Khadka NK. Kinetic Defects Induced by Melittin in Model Lipid Membranes: A Solution Atomic Force Microscopy Study. J Phys Chem B 2016; 120:4625-34. [PMID: 27167473 DOI: 10.1021/acs.jpcb.6b02332] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Quantitative characterization of membrane defects (pores) is important for elucidating the molecular basis of many membrane-active peptides. We study kinetic defects induced by melittin in vesicular and planar lipid bilayers. Fluorescence spectroscopy measurements indicate that melittin induces time-dependent calcein leakage. Solution atomic force microscopy (AFM) is used to visualize melittin-induced membrane defects. After initial equilibration, the most probable defect radius is ∼3.8 nm in 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) bilayers. Unexpectedly, defects become larger with longer incubation, accompanied by substantial shape transformation. The initial defect radius is ∼4.7 nm in 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) bilayers. Addition of 30 mol % cholesterol to DOPC bilayers suppresses defect kinetics, although the inhibitory impact is negated by longer incubation. Overall, the kinetic rate of defect development follows DLPC > DOPC > DOPC/cholesterol. Kinetic defects are also observed when anionic lipids are present. Based on the observation that defects can occupy as large as 40% of the bilayer surface, we propose a kinetic defect growth model. We also study the effect of melittin on the phase behavior of DOPC/egg-sphingomyelin/cholesterol bilayers. We find that melittin initially suppresses or eliminates liquid-ordered (Lo) domains; Lo domains gradually emerge and become the dominant species with longer incubation; and defects in phase-coexisting bilayers have a most probable radius of ∼5 nm and are exclusively localized in the liquid-disordered (Ld) phase. Our experimental data highlight that melittin-induced membrane defects are not static; conversely, spontaneous defect growth is intrinsically associated with membrane permeabilization exerted by melittin.
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Affiliation(s)
- Jianjun Pan
- Department of Physics, University of South Florida , Tampa, Florida 33620, United States
| | - Nawal K Khadka
- Department of Physics, University of South Florida , Tampa, Florida 33620, United States
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27
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Juhaniewicz J, Sek S. Interaction of Melittin with Negatively Charged Lipid Bilayers Supported on Gold Electrodes. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2015.11.134] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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28
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Matyszewska D, Bilewicz R, Su Z, Abbasi F, Leitch JJ, Lipkowski J. PM-IRRAS Studies of DMPC Bilayers Supported on Au(111) Electrodes Modified with Hydrophilic Monolayers of Thioglucose. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:1791-1798. [PMID: 26829620 DOI: 10.1021/acs.langmuir.5b04052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A phospholipid bilayer composed of 1,2-dimyristoyl-d54-sn-glycero-3-phosphocholine (d54-DMPC) was deposited onto the Au(111) electrode modified with a self-assembled monolayer of 1-thio-β-d-glucose (β-Tg) via the Langmuir-Blodgett and Langmuir-Schaefer (LB-LS) techniques. Polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) measurements were used to characterize structural and orientational changes in this model biological membrane on a hydrophilic surface modified gold electrode. The results of the spectroscopic measurements showed that the tilt angle of acyl chains obtained for deuterated DMPC bilayers supported on the β-Tg-modified gold is significantly lower than that reported previously for DMPC bilayers deposited directly on Au(111) electrodes. Moreover, tilt angles of ∼18° were obtained for d54-DMPC bilayers on β-Tg self-assembled monolayers (SAMs) at positive potentials, which are similar to the values calculated for h-DMPC deposited on bare gold in the desorbed state and to those observed for a stack of hydrated DMPC bilayers. This data confirms that the β-thioglucose SAM promotes the formation of a water cushion that separates the phospholipid bilayer from the metal surface. As a result, the DMPC polar heads are not in direct contact with the electrode and can adopt a zigzag configuration, which strengthens the chain-chain interactions and allows for an overall decrease in the tilt of the acyl chains. These novel supported model membranes may be especially useful in studies pertaining to the incorporation of peptides and proteins into phospholipid bilayers.
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Affiliation(s)
- Dorota Matyszewska
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw , Żwirki i Wigury 101, 02089 Warsaw, Poland
| | - Renata Bilewicz
- Faculty of Chemistry, University of Warsaw , ul. Pasteura 1, 02093 Warsaw, Poland
| | - ZhangFei Su
- Department of Chemistry, University of Guelph , Guelph, Ontario N1G 2W1, Canada
| | - Fatemah Abbasi
- Department of Chemistry, University of Guelph , Guelph, Ontario N1G 2W1, Canada
| | - J Jay Leitch
- Department of Chemistry, University of Guelph , Guelph, Ontario N1G 2W1, Canada
| | - Jacek Lipkowski
- Department of Chemistry, University of Guelph , Guelph, Ontario N1G 2W1, Canada
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29
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Pawłowski J, Juhaniewicz J, Güzeloğlu A, Sęk S. Mechanism of Lipid Vesicles Spreading and Bilayer Formation on a Au(111) Surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:11012-9. [PMID: 26010469 DOI: 10.1021/acs.langmuir.5b01331] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Spreading of small unilamellar vesicles on solid surfaces is one of the most common ways to obtain supported lipid bilayers. Although the method has been used successfully for many years, the details of this process are still the subject of intense debate. Particularly controversial is the mechanism of bilayer formation on metallic surfaces like gold. In this work, we have employed scanning probe microscopy techniques to evaluate the details of lipid vesicles spreading and formation of the lipid bilayer on a Au(111) surface in a phosphate-buffered saline solution. Nanoscale imaging revealed that the mechanism of this process differs significantly from that usually assumed for hydrophilic surfaces such as mica, glass, and silicon oxide. Formation of the bilayer on gold involves several steps. Initially, the vesicles accumulate on a gold surface and release lipid molecules that adsorb on a Au(111) surface, giving rise to the appearance of highly ordered stripelike domains. The latter serve as a template for the buildup of a hemimicellar film, which contributes to the increased hydrophilicity of the external surface and facilitates further adsorption and rupture of the vesicles. As a result, the bilayer is spread over a hemimicellar film, and then it is followed by slow fusion between coupled layers leading to formation of a single bilayer supported on a gold surface. We believe that the results presented in this work may provide some new insights into the area of research related to supported lipid bilayers.
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Affiliation(s)
- Jan Pawłowski
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw , Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Joanna Juhaniewicz
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw , Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Alişan Güzeloğlu
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw , Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Sławomir Sęk
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw , Żwirki i Wigury 101, 02-089 Warsaw, Poland
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