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Sut TN, Jackman JA, Cho NJ. Cholesterol-Enriched Hybrid Lipid Bilayer Formation on Inverse Phosphocholine Lipid-Functionalized Titanium Oxide Surfaces. Biomimetics (Basel) 2023; 8:588. [PMID: 38132527 PMCID: PMC10741646 DOI: 10.3390/biomimetics8080588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/29/2023] [Accepted: 12/02/2023] [Indexed: 12/23/2023] Open
Abstract
Hybrid lipid bilayers (HLBs) are rugged biomimetic cell membrane interfaces that can form on inorganic surfaces and be designed to contain biologically important components like cholesterol. In general, HLBs are formed by depositing phospholipids on top of a hydrophobic self-assembled monolayer (SAM) composed of one-tail amphiphiles, while recent findings have shown that two-tail amphiphiles such as inverse phosphocholine (CP) lipids can have advantageous properties to promote zwitterionic HLB formation. Herein, we explored the feasibility of fabricating cholesterol-enriched HLBs on CP SAM-functionalized TiO2 surfaces with the solvent exchange and vesicle fusion methods. All stages of the HLB fabrication process were tracked by quartz crystal microbalance-dissipation (QCM-D) measurements and revealed important differences in fabrication outcome depending on the chosen method. With the solvent exchange method, it was possible to fabricate HLBs with well-controlled cholesterol fractions up to ~65 mol% in the upper leaflet as confirmed by a methyl-β-cyclodextrin (MβCD) extraction assay. In marked contrast, the vesicle fusion method was only effective at forming HLBs from precursor vesicles containing up to ~35 mol% cholesterol, but this performance was still superior to past results on hydrophilic SiO2. We discuss the contributing factors to the different efficiencies of the two methods as well as the general utility of two-tail CP SAMs as favorable interfaces to incorporate cholesterol into HLBs. Accordingly, our findings support that the solvent exchange method is a versatile tool to fabricate cholesterol-enriched HLBs on CP SAM-functionalized TiO2 surfaces.
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Affiliation(s)
- Tun Naw Sut
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore;
- School of Chemical Engineering and Translational Nanobioscience Research Center, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Joshua A. Jackman
- School of Chemical Engineering and Translational Nanobioscience Research Center, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Nam-Joon Cho
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore;
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2
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Melcrová A, Maity S, Melcr J, de Kok NAW, Gabler M, van der Eyden J, Stensen W, Svendsen JSM, Driessen AJM, Marrink SJ, Roos WH. Lateral membrane organization as target of an antimicrobial peptidomimetic compound. Nat Commun 2023; 14:4038. [PMID: 37419980 PMCID: PMC10328936 DOI: 10.1038/s41467-023-39726-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 06/20/2023] [Indexed: 07/09/2023] Open
Abstract
Antimicrobial resistance is one of the leading concerns in medical care. Here we study the mechanism of action of an antimicrobial cationic tripeptide, AMC-109, by combining high speed-atomic force microscopy, molecular dynamics, fluorescence assays, and lipidomic analysis. We show that AMC-109 activity on negatively charged membranes derived from Staphylococcus aureus consists of two crucial steps. First, AMC-109 self-assembles into stable aggregates consisting of a hydrophobic core and a cationic surface, with specificity for negatively charged membranes. Second, upon incorporation into the membrane, individual peptides insert into the outer monolayer, affecting lateral membrane organization and dissolving membrane nanodomains, without forming pores. We propose that membrane domain dissolution triggered by AMC-109 may affect crucial functions such as protein sorting and cell wall synthesis. Our results indicate that the AMC-109 mode of action resembles that of the disinfectant benzalkonium chloride (BAK), but with enhanced selectivity for bacterial membranes.
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Affiliation(s)
- Adéla Melcrová
- Molecular Biophysics, Zernike Institute for Advanced Materials, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Sourav Maity
- Molecular Biophysics, Zernike Institute for Advanced Materials, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Josef Melcr
- Molecular Dynamics, Groningen Biomolecular Sciences & Biotechnology Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Niels A W de Kok
- Molecular Microbiology, Groningen Biomolecular Sciences & Biotechnology Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Mariella Gabler
- Molecular Biophysics, Zernike Institute for Advanced Materials, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Jonne van der Eyden
- Molecular Biophysics, Zernike Institute for Advanced Materials, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Wenche Stensen
- Department of Chemistry, UiT Arctic University of Norway, Tromsø, Norway
| | - John S M Svendsen
- Department of Chemistry, UiT Arctic University of Norway, Tromsø, Norway
| | - Arnold J M Driessen
- Molecular Microbiology, Groningen Biomolecular Sciences & Biotechnology Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Siewert J Marrink
- Molecular Biophysics, Zernike Institute for Advanced Materials, Rijksuniversiteit Groningen, Groningen, the Netherlands
- Molecular Dynamics, Groningen Biomolecular Sciences & Biotechnology Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Wouter H Roos
- Molecular Biophysics, Zernike Institute for Advanced Materials, Rijksuniversiteit Groningen, Groningen, the Netherlands.
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Altunayar-Unsalan C, Unsalan O, Mavromoustakos T. Molecular interactions of hesperidin with DMPC/cholesterol bilayers. Chem Biol Interact 2022; 366:110131. [PMID: 36037876 DOI: 10.1016/j.cbi.2022.110131] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 08/05/2022] [Accepted: 08/20/2022] [Indexed: 11/03/2022]
Abstract
Since cell membranes are complex systems, the use of model lipid bilayers is quite important for the study of their interactions with bioactive molecules. Mammalian cell membranes require cholesterol (CHOL) for their structure and function. For this reason, the mixtures of phospholipid and cholesterol are necessary to use in model membrane studies to better simulate the real systems. In the present study, we investigated the effect of the incorporation of hesperidin in model membranes consisting of dimyristoylphosphatidylcholine (DMPC) and CHOL by using differential scanning calorimetry (DSC), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and atomic force microscopy (AFM). ATR-FTIR results demonstrated that hesperidin increases the fluidity of the DMPC/CHOL binary system. DSC findings indicated that the presence of 5 mol% hesperidin induces a broadening of the main phase transition consisting of three overlapping components. AFM experiments showed that hesperidin increases the thickness of DMPC/CHOL lipid bilayer model membranes. In addition to experimental results, molecular docking studies were conducted with hesperidin and human lanosterol synthase (LS), which is an enzyme found in the final step of cholesterol synthesis, to characterize hesperidin's interactions with its surrounding via its hydroxyl and oxygen groups. Then, hesperidin's ADME/Tox (absorption, distribution, metabolism, excretion and toxicity) profile was computed to see the potential impact on living system. In conclusion, considering the data obtained from experimental studies, this work ensures molecular insights in the interaction between a flavonoid, as an antioxidant drug model, and lipids mimicking those found in mammalian membranes. Moreover, computational studies demonstrated that hesperidin may be a great potential for use as a therapeutic agent for hypercholesterolemia due to its antioxidant property.
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Affiliation(s)
- Cisem Altunayar-Unsalan
- Ege University Central Research Testing and Analysis Laboratory Research and Application Center, 35100, Bornova, Izmir, Turkey.
| | - Ozan Unsalan
- Ege University, Faculty of Science, Department of Physics, 35100, Bornova, Izmir, Turkey.
| | - Thomas Mavromoustakos
- Section of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, 15771, Greece.
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4
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Capability of Polyunsaturated Phosphatidylcholine for Non-raft Domain Formation in Cholesterol-containing Lipid Bilayers. E-JOURNAL OF SURFACE SCIENCE AND NANOTECHNOLOGY 2022. [DOI: 10.1380/ejssnt.2022-015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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5
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Non-raft submicron domain formation in cholesterol-containing lipid bilayers induced by polyunsaturated phosphatidylethanolamine. Colloids Surf B Biointerfaces 2021; 210:112235. [PMID: 34891064 DOI: 10.1016/j.colsurfb.2021.112235] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/08/2021] [Accepted: 11/16/2021] [Indexed: 12/13/2022]
Abstract
Domain formation in "HLC" ternary lipid bilayers, comprising a high transition temperature (High-Tm) lipid, a Low-Tm lipid, and cholesterol (Chol), has been extensively studied as raft-resembling systems. Recently, we reported the formation of submicron domains in an "LLC" lipid bilayer, encompassing Low-Tm phosphatidylethanolamine (PE), Low-Tm phosphatidylcholine (PC), and Chol. We hypothesized that the formation of this unique domain is driven by polyunsaturated PE. In this study, we explored the effects of the degree of PE unsaturation and the double bond distribution at the sn-position on the mechanism of formation and the composition of submicron domains. Supported lipid bilayers (SLBs), comprising PE with various degrees of unsaturation, monounsaturated PC (POPC), and Chol, were investigated using fluorescence microscopy, atomic force microscopy, and the force-distance curve measurement. The area fraction of submicron domains in PE+POPC+Chol-SLB increased with the PE concentration and degree of unsaturation of the PE acyl chain. The results indicated that the submicron domains were enriched with polyunsaturated PE and were in the liquid-disordered-like state, whereas their surrounding regions were in the liquid-ordered-like state. Segregation of polyunsaturated PE from the Chol-containing region generated submicron domains in the LLC lipid bilayer. We propose a mechanism for the formation of these submicron domains based on molecular interactions involving the hydrophobic and hydrophilic parts of the bilayer membrane.
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6
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Effects of ethanol and n-butanol on the fluidity of supported lipid bilayers. Chem Phys Lipids 2021; 238:105091. [PMID: 33992653 DOI: 10.1016/j.chemphyslip.2021.105091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 05/05/2021] [Accepted: 05/11/2021] [Indexed: 11/21/2022]
Abstract
The interactions of molecules such as short-chain alcohols with the mammalian plasma membrane are thought to play a role in anesthetic effects. We have examined the concentration-dependent effects of ethanol and n-butanol on the fluidity of planar model lipid bilayer structures supported on mica. The supported model bilayer was composed of 1,2-dioleoyl-sn-phosphatidylcholine (DOPC), cholesterol, and sphingomyelin, and the bilayers were formed by vesicle fusion from extruded unilamellar vesicles (133 nm diameter, polydispersity index of 0.17). Controlled amounts of ethanol and n-butanol were added during vesicle deposition. Translational diffusion constants were obtained utilizing fluorescence recovery after photobleaching (FRAP) measurements on the micrometer scale with perylene as the fluorophore. The translational diffusion constants increased and then decreased with increasing ethanol concentration, with the bilayer structure degrading at ca. 0.8 M ethanol. A similar trend was observed for n-butanol at lower alcohol concentrations owing to greater interactions with phospholipid bilayer constituents. For n-butanol, the integrity of the planar bilayer structure deteriorated at ca. 0.4 M n-butanol. The results are consistent with bilayer interdigitation.
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7
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Goh MWS, Tero R. Cholesterol-induced microdomain formation in lipid bilayer membranes consisting of completely miscible lipids. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183626. [PMID: 33901442 DOI: 10.1016/j.bbamem.2021.183626] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 11/19/2022]
Abstract
Recently, we reported that a ternary lipid bilayer comprising phosphatidylethanolamine (PE), phosphatidylcholine (PC), which were both derived from chicken egg, and cholesterol (Chol) generates microdomains that function as specific fusion sites for proteoliposomes. Chol-induced microdomain formation in a completely miscible lipid bilayer is an exceptional phenomenon. Numerous studies have elucidated the formation of domains in liquid ordered (Lo) and liquid disordered (Ld) phases of ternary bilayers, which comprise two partially miscible lipids and Chol. Herein, we investigated the composition and mechanism of formation of these unique microdomains in supported lipid bilayers (SLBs) using a fluorescence microscope and an atomic force microscope (AFM). We prepared ternary SLBs using egg-derived PC (eggPC), Chol and three different types of PE: egg-derived PE, 1-palmitoyl-2-oleoyl-PE, and 1,2-didocosahexaenoyl-PE (diDHPE). Fluorescence microscopy observations revealed that fluid and continuous SLBs were formed at PE concentrations (CPE) of ≥6 mol%. Fluorescence recovery after photobleaching measurement revealed that the microdomain was more fluid than the surrounding region that showed typical diffusion coefficient of the Lo phase. The microdomains were observed as depressions in the AFM topographies. Their area fraction (θ) increased with CPE, and diDHPE produced a significantly large θ among the three PEs. The microdomains in the PE+eggPC+Chol-SLBs were rich in polyunsaturated PE and were in the Ld-like phase. Associating eggPC and Chol caused polyunsaturated PE to segregate, resulting in a microdomain formation by conferring the umbrella effect on Chol, entropic effect of disordered acyl chains, and π-π interactions in the hydrophobic core.
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Affiliation(s)
- Melvin Wei Shern Goh
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan
| | - Ryugo Tero
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan.
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8
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Nahmad-Rohen A, Regan D, Masia F, McPhee C, Pope I, Langbein W, Borri P. Quantitative Label-Free Imaging of Lipid Domains in Single Bilayers by Hyperspectral Coherent Raman Scattering. Anal Chem 2020; 92:14657-14666. [PMID: 33090767 PMCID: PMC7660592 DOI: 10.1021/acs.analchem.0c03179] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Lipid phase separation in cellular membranes is thought to play an important role in many biological functions. This has prompted the development of synthetic membranes to study lipid-lipid interactions in vitro, alongside optical microscopy techniques aimed at directly visualizing phase partitioning. In this context, there is a need to overcome the limitations of fluorescence microscopy, where added fluorophores can significantly perturb lipid packing. Raman-based optical imaging is a promising analytical tool for label-free chemically specific microscopy of lipid bilayers. In this work, we demonstrate the application of hyperspectral coherent Raman scattering microscopy combined with a quantitative unsupervised data analysis methodology developed in-house to visualize lipid partitioning in single planar membrane bilayers exhibiting liquid-ordered and liquid-disordered domains. Two home-built instruments were utilized, featuring coherent anti-Stokes Raman scattering and stimulated Raman scattering modalities. Ternary mixtures of dioleoylphosphatidylcholine, sphingomyelin, and cholesterol were used to form phase-separated domains. We show that domains are consistently resolved, both chemically and spatially, in a completely label-free manner. Quantitative Raman susceptibility spectra of the domains are provided alongside their spatially resolved concentration maps.
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Affiliation(s)
| | - David Regan
- School of Physics & Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA, U.K
| | - Francesco Masia
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, U.K
| | - Craig McPhee
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, U.K
| | - Iestyn Pope
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, U.K
| | - Wolfgang Langbein
- School of Physics & Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA, U.K
| | - Paola Borri
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, U.K
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9
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Abstract
Many critical biological events, including biochemical signaling, membrane traffic, and cell motility, originate at membrane surfaces. Each such event requires that members of a specific group of proteins and lipids rapidly assemble together at a specific site on the membrane surface. Understanding the biophysical mechanisms that stabilize these assemblies is critical to decoding and controlling cellular functions. In this article, we review progress toward a quantitative biophysical understanding of the mechanisms that drive membrane heterogeneity and organization. We begin from a physical perspective, reviewing the fundamental principles and key experimental evidence behind each proposed mechanism. We then shift to a biological perspective, presenting key examples of the role of heterogeneity in biology and asking which physical mechanisms may be responsible. We close with an applied perspective, noting that membrane heterogeneity provides a novel therapeutic target that is being exploited by a growing number of studies at the interface of biology, physics, and engineering.
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Affiliation(s)
- Wade F Zeno
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Kasey J Day
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Vernita D Gordon
- Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
- Center for Nonlinear Dynamics, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Jeanne C Stachowiak
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
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10
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Low-Level Organic Solvents Improve Multienzyme Whole-Cell Catalytic Synthesis of Myricetin-7-O-Glucuronide. Catalysts 2019. [DOI: 10.3390/catal9110970] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Multienzyme whole-cell biocatalysts are preferred in industrial applications, and two major concerns regarding the use of these biocatalysts, cell viability and cell membrane integrity, must be addressed. In this work, the transformation of myricetin to myricetin-7-O-glucuronide catalyzed by an engineered Escherichia coli strain was taken as the model reaction to examine the impacts of low-level organic solvents on whole-cell biocatalysis. Low-level organic solvents (2%, v/v) showed a significant increase (roughly 13-fold) in myricetin-7-O-glucuronide yields. No obvious compromises of cellular viability and integrity were observed by a flow cytometry assay or in the determination of extracellular protein leakage, suggesting the addition of low-level organic solvents accommodates whole E. coli cells. Furthermore, a scaled-up reaction was conducted to test the capability and efficiency of whole-cell catalysis in the presence of organic solvents. This study presents a promising and simple means to enhance the productivity of multienzyme whole-cell catalysis without losing the barrier functions of the cell membrane.
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Kumari P, Kumari M, Kashyap HK. Counter-effects of Ethanol and Cholesterol on the Heterogeneous PSM–POPC Lipid Membrane: A Molecular Dynamics Simulation Study. J Phys Chem B 2019; 123:9616-9628. [DOI: 10.1021/acs.jpcb.9b07107] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Pratibha Kumari
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Monika Kumari
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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12
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Duarte AA, Marquês JT, Brasil F, Viana AS, Tavares P, Raposo M. In Situ AFM Imaging of Adsorption Kinetics of DPPG Liposomes: A Quantitative Analysis of Surface Roughness. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2019; 25:798-809. [PMID: 30919801 DOI: 10.1017/s1431927619000345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The adsorption of intact liposomes on surfaces is of great importance for the development of sensors and drug delivery systems and, also, strongly dependent on the surface roughness where the liposomes are adsorbed. In this paper, we analyzed, by using atomic force microscopy in liquid, the evolution of the morphology of gold surfaces and of poly(allylamine hydrochloride) (PAH) surfaces with different roughness during the adsorption of liposomes prepared with the synthetic phospholipid 1,2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)]. Our results reveal the following. On smooth surfaces of Au only and Au with PAH, the liposomes open and deploy on the substrate, creating a supported-lipid bilayer, with the opening process being faster on the Au/PAH surface. On rough substrates of Au coated with polyelectrolyte multilayers, the liposomes were adsorbed intact on the surface. This was corroborated by power spectral density analysis that demonstrates the presence of superstructures with an average lateral size of 43 and 87 nm, in accordance with two and four times the mean liposome hydrodynamic diameter of about 21 nm. In addition, this work presents an adequate and effective methodology for analysis of adsorption phenomena of liposomes on rough surfaces.
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Affiliation(s)
- Andreia A Duarte
- CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, FCT,Universidade Nova de Lisboa,2829-516 Caparica,Portugal
| | - Joaquim T Marquês
- Centro de Química e Bioquímica, Faculdade de Ciências da Universidade de Lisboa,Ed. C8, Campo Grande 1749-016, Lisboa,Portugal
| | - Francisco Brasil
- CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, FCT,Universidade Nova de Lisboa,2829-516 Caparica,Portugal
| | - Ana S Viana
- Centro de Química e Bioquímica, Faculdade de Ciências da Universidade de Lisboa,Ed. C8, Campo Grande 1749-016, Lisboa,Portugal
| | - Pedro Tavares
- REQUIMTE, Departamento de Química,Faculdade de Ciências e Tecnologia, UNL,Campus de Caparica, 2829-516 Caparica,Portugal
| | - Maria Raposo
- CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, FCT,Universidade Nova de Lisboa,2829-516 Caparica,Portugal
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Dols-Perez A, Fumagalli L, Gomila G. Interdigitation in spin-coated lipid layers in air. Colloids Surf B Biointerfaces 2018; 172:400-406. [PMID: 30195157 DOI: 10.1016/j.colsurfb.2018.08.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/14/2018] [Accepted: 08/19/2018] [Indexed: 10/28/2022]
Abstract
In this study, we show that dry saturated phospholipid layers prepared by the spin-coating technique could present thinner regions associated to interdigitated phases under some conditions. The morphological characteristics of lipid layers of saturated phosphocholines, such as dilauroylphosphatidylcholine (DLPC), dimyristoylphosphatidylcholine (DMPC), dipalmitoylphosphatidylcholine (DPPC) and distearoylphosphatidylcholine (DSPC), have been measured by Atomic Force Microscopy and revealed that the presence of interdigitated regions is not induced by the same parameters that induce them in hydrated samples. To achieve these results the effect of the lipid hidrocabonated chain length, the presence of alcohol in the coating solution, the spinning velocity and the presence of cholesterol were tested. We showed that DPPC and DSPC bilayers, on the one side, can show structures with similar height than interdigitated regions observed in hydrated samples, while, on the other side, DLPC and DMPC tend to show no evidence of interdigitation. Results indicate that the presence of interdigitated areas is due to the presence of lateral tensions and, hence, that they can be eliminated by releasing these tensions by, for instance, the addition of cholesterol. These results demonstrate that interdigitation in lipid layers is a rather general phenomena and can be observed in lipid bilayers in dry conditions.
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Affiliation(s)
- Aurora Dols-Perez
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, 2629 HZ, Delft, Netherlands.
| | - Laura Fumagalli
- School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Gabriel Gomila
- Institut de Bioenginyeria de Catalunya (IBEC), C/ Baldiri i Reixac 15-21, 08028, Barcelona, Spain; Departament d'Enginyeria Electrònica i Biomèdica, Universitat de Barcelona, C/ Martí i Franquès 1, 08028, Barcelona, Spain
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14
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Polley A. Partition of common anesthetic molecules in the liquid disordered phase domain of a composite multicomponent membrane. Phys Rev E 2018; 98:012409. [PMID: 30110859 DOI: 10.1103/physreve.98.012409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Indexed: 01/04/2023]
Abstract
Despite a vast clinical application of anesthetics, the molecular level of understanding of general anesthesia is far from our reach. Using atomistic molecular dynamics simulation, we study the effects of common anesthetics: ethanol, chloroform, and methanol in the fully hydrated symmetric multicomponent lipid bilayer membrane comprised of an unsaturated palmitoyl-oleoyl-phosphatidyl-choline (POPC), a saturated palmitoyl-sphingomyelin, and cholesterol, which exhibits phase coexistence of liquid-ordered (l_{o})-liquid-disordered (l_{d}) phase domains. We find that the mechanical and physical properties such as the thickness and rigidity of the membrane are reduced while the lateral expansion of the membrane is exhibited in the presence of anesthetic molecules. Our simulation shows both lateral and transverse heterogeneity of the anesthetics in the composite multicomponent lipid membrane. Both ethanol and chloroform partition in the POPC-rich l_{d} phase domain, while methanol is distributed in both l_{o}-l_{d} phase domains. Chloroform can penetrate deep into the membrane, while methanol partitions mostly at the water layer closed to the head group and ethanol at the neck of the lipids in the membrane.
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Affiliation(s)
- Anirban Polley
- Department of Chemical Engineering, Columbia University, New York City, New York 10027, USA
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15
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Dhanasekaran M, Jaganathan M, Dhathathreyan A. Colloids versus solution state adsorption of proteins: Interaction of Myoglobin with supported lipid bilayers. Int J Biol Macromol 2018; 114:434-440. [PMID: 29555511 DOI: 10.1016/j.ijbiomac.2018.03.078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 03/16/2018] [Indexed: 11/15/2022]
Abstract
This study examines adsorption of Myoglobin (Mb) in solution and as colloid on supported lipid bilayers of neutral phospholipids and a mixture of neutral+cationic lipids formed on gold coated quartz in a Quartz crystal microbalance (QCM). Results indicate that thin adsorbed films of Mb in solution and as colloids, show atleast 3 steps in the interaction with the bilayers: i) An initial strain of a viscoelastic film ii) Entrained water that moves in and out of the adsorbed film and iii) The coupled load from the bulk liquid which increases the strain of the film. These three components constitute an effective viscoelastic film which is rigidly coupled to the QCM. Grazing incidence XRD (GIXD) shows that the bilayer head group remains nearly undisturbed for Mb solution with pure (neutral) and (neutral+cationic) mixtures, whereas for the colloids there is an increase in head group thickness with neutral and decrease in the case of mixture. Unsaturation in the alkyl tails in the neutral lipid resulting in flexible disordered bilayers and more entrained water in the cationic system results in these changes. The sensitivity of QCM-D, makes it useful to study real-time monitoring of bilayer structural robustness cytotoxicity, drug delivery and lipid self-assembly.
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Affiliation(s)
| | | | - A Dhathathreyan
- Advanced Materials Lab., CSIR-CLRI, Adyar, Chennai 600020, India.
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16
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Lupino KM, Romano KA, Simons MJ, Gregg JT, Panepinto L, Cruz GM, Grajek L, Caputo GA, Hickman MJ, Hecht GB. A Recurrent Silent Mutation Implicates fecA in Ethanol Tolerance by Escherichia coli. BMC Microbiol 2018; 18:36. [PMID: 29669516 PMCID: PMC5907409 DOI: 10.1186/s12866-018-1180-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 04/09/2018] [Indexed: 12/21/2022] Open
Abstract
Background An issue associated with efficient bioethanol production is the fact that the desired product is toxic to the biocatalyst. Among other effects, ethanol has previously been found to influence the membrane of E. coli in a dose-dependent manner and induce changes in the lipid composition of the plasma membrane. We describe here the characterization of a collection of ethanol-tolerant strains derived from the ethanologenic Escherichia coli strain FBR5. Results Membrane permeability assays indicate that many of the strains in the collection have alterations in membrane permeability and/or responsiveness of the membrane to environmental changes such as temperature shifts or ethanol exposure. However, analysis of the strains by gas chromatography and mass spectrometry revealed no qualitative changes in the acyl chain composition of membrane lipids in response to ethanol or temperature. To determine whether these strains contain any mutations that might contribute to ethanol tolerance or changes in membrane permeability, we sequenced the entire genome of each strain. Unexpectedly, none of the strains displayed mutations in genes known to control membrane lipid synthesis, and a few strains carried no mutations at all. Interestingly, we found that four independently-isolated strains acquired an identical C → A (V244 V) silent mutation in the ferric citrate transporter gene fecA. Further, we demonstrated that either a deletion of fecA or over-expression of fecA can confer increased ethanol survival, suggesting that any misregulation of fecA expression affects the cellular response to ethanol. Conclusions The fact that no mutations were observed in several ethanol-tolerant strains suggested that epigenetic mechanisms play a role in E. coli ethanol tolerance and membrane permeability. Our data also represent the first direct phenotypic evidence that the fecA gene plays a role in ethanol tolerance. We propose that the recurring silent mutation may exert an effect on phenotype by altering RNA-mediated regulation of fecA expression. Electronic supplementary material The online version of this article (10.1186/s12866-018-1180-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Katherine M Lupino
- Center of Mitochondrial and Epigenomic Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Chemistry & Biochemistry, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA
| | - Kymberleigh A Romano
- Department of Cellular & Molecular Medicine, Cleveland Clinic, Cleveland, OH, USA.,Department of Biological Sciences, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA
| | - Matthew J Simons
- Department of Molecular Genetics and Microbiology, Molecular and Cellular Biology, Stony Brook University, Stony Brook, NY, USA
| | - John T Gregg
- Department of Microbiology, University of Pennsylvania, Philadelphia, PA, USA.,Department of Chemistry & Biochemistry, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA
| | - Leanna Panepinto
- School of Osteopathic Medicine, Rowan University, Stratford, NJ, USA.,Department of Biological Sciences, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA
| | - Ghislaine M Cruz
- Department of Biomedical and Health Sciences, Rutgers University, New Brunswick, NJ, USA.,Department of Chemistry & Biochemistry, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA
| | - Lauren Grajek
- Revlon Research Center, Edison, NJ, USA.,Department of Chemistry & Biochemistry, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA
| | - Gregory A Caputo
- Department of Chemistry & Biochemistry, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA.,Department of Molecular & Cellular Biosciences, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA
| | - Mark J Hickman
- Department of Molecular & Cellular Biosciences, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA
| | - Gregory B Hecht
- Department of Biological Sciences, Rowan University, 201 Mullica Hill Rd, Glassboro, NJ, 08028, USA.
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17
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Sato Y, Hiratsuka Y, Kawamata I, Murata S, Nomura SIM. Micrometer-sized molecular robot changes its shape in response to signal molecules. Sci Robot 2017; 2:2/4/eaal3735. [DOI: 10.1126/scirobotics.aal3735] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 02/03/2017] [Indexed: 11/02/2022]
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18
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dos Santos AG, Marquês JT, Carreira AC, Castro IR, Viana AS, Mingeot-Leclercq MP, de Almeida RFM, Silva LC. The molecular mechanism of Nystatin action is dependent on the membrane biophysical properties and lipid composition. Phys Chem Chem Phys 2017; 19:30078-30088. [DOI: 10.1039/c7cp05353c] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nystatin-induced membrane permeabilization is related to its effects on membrane properties and organization.
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Affiliation(s)
- A. G. dos Santos
- iMed.ULisboa – Research Institute for Medicines
- Faculdade de Farmácia
- Universidade de Lisboa
- 1649-003 Lisboa
- Portugal
| | - J. T. Marquês
- CQB – Centre for Chemistry and Biochemistry, Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - A. C. Carreira
- iMed.ULisboa – Research Institute for Medicines
- Faculdade de Farmácia
- Universidade de Lisboa
- 1649-003 Lisboa
- Portugal
| | - I. R. Castro
- iMed.ULisboa – Research Institute for Medicines
- Faculdade de Farmácia
- Universidade de Lisboa
- 1649-003 Lisboa
- Portugal
| | - A. S. Viana
- CQB – Centre for Chemistry and Biochemistry, Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - M.-P. Mingeot-Leclercq
- FACM/LDRI-UCL – Cellular and Molecular Pharmacology unit of the Louvain Drug Research Institute
- Université Catholique de Louvain
- B-1200 Bruxelles
- Belgium
| | - R. F. M. de Almeida
- CQB – Centre for Chemistry and Biochemistry, Faculdade de Ciências
- Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - L. C. Silva
- iMed.ULisboa – Research Institute for Medicines
- Faculdade de Farmácia
- Universidade de Lisboa
- 1649-003 Lisboa
- Portugal
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19
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Bleecker JV, Cox PA, Foster RN, Litz JP, Blosser MC, Castner DG, Keller SL. Thickness Mismatch of Coexisting Liquid Phases in Noncanonical Lipid Bilayers. J Phys Chem B 2016; 120:2761-70. [PMID: 26890258 DOI: 10.1021/acs.jpcb.5b10165] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Lipid composition dictates membrane thickness, which in turn can influence membrane protein activity. Lipid composition also determines whether a membrane demixes into coexisting liquid-crystalline phases. Previous direct measurements of demixed lipid membranes have always found a liquid-ordered phase that is thicker than the liquid-disordered phase. Here we investigated noncanonical ternary lipid mixtures designed to produce bilayers with thicker disordered phases than ordered phases. The membranes were composed of short, saturated (ordered) lipids; long, unsaturated (disordered) lipids; and cholesterol. We found that few of these systems yield coexisting liquid phases above 10 °C. For membranes that do demix into two liquid phases, we measured the thickness mismatch between the phases by atomic force microscopy and found that not one of the systems yields thicker disordered than ordered phases under standard experimental conditions. We found no monotonic relationship between demixing temperatures of these ternary systems and either estimated thickness mismatches between the liquid phases or the physical parameters of single-component membranes composed of the individual lipids. These results highlight the robustness of a membrane's liquid-ordered phase to be thicker than the liquid-disordered phase, regardless of the membrane's lipid composition.
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Affiliation(s)
- Joan V Bleecker
- Departments of Chemistry, ‡Chemical Engineering, and §Bioengineering, University of Washington , Seattle, Washington 98195, United States
| | - Phillip A Cox
- Departments of Chemistry, ‡Chemical Engineering, and §Bioengineering, University of Washington , Seattle, Washington 98195, United States
| | - Rami N Foster
- Departments of Chemistry, ‡Chemical Engineering, and §Bioengineering, University of Washington , Seattle, Washington 98195, United States
| | - Jonathan P Litz
- Departments of Chemistry, ‡Chemical Engineering, and §Bioengineering, University of Washington , Seattle, Washington 98195, United States
| | - Matthew C Blosser
- Departments of Chemistry, ‡Chemical Engineering, and §Bioengineering, University of Washington , Seattle, Washington 98195, United States
| | - David G Castner
- Departments of Chemistry, ‡Chemical Engineering, and §Bioengineering, University of Washington , Seattle, Washington 98195, United States
| | - Sarah L Keller
- Departments of Chemistry, ‡Chemical Engineering, and §Bioengineering, University of Washington , Seattle, Washington 98195, United States
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20
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Paiva TO, Bastos AEP, Marquês JT, Viana AS, Lima PA, de Almeida RFM. m-Cresol affects the lipid bilayer in membrane models and living neurons. RSC Adv 2016. [DOI: 10.1039/c6ra20337j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A preferential interaction of m-cresol with high dipole-potential cholesterol/sphingomyelin-enriched lipid domains jeopardizes membrane integrity, explaining the toxicity of m-cresol-containing insulin formulations.
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Affiliation(s)
- T. O. Paiva
- Centro de Química e Bioquímica
- DQB
- Faculdade de Ciências da Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - A. E. P. Bastos
- Centro de Química e Bioquímica
- DQB
- Faculdade de Ciências da Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - J. T. Marquês
- Centro de Química e Bioquímica
- DQB
- Faculdade de Ciências da Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - A. S. Viana
- Centro de Química e Bioquímica
- DQB
- Faculdade de Ciências da Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
| | - P. A. Lima
- NOVA Medical School
- Faculdade de Ciências Médicas da Universidade Nova de Lisboa
- 1169-056 Lisboa
- Portugal
| | - R. F. M. de Almeida
- Centro de Química e Bioquímica
- DQB
- Faculdade de Ciências da Universidade de Lisboa
- 1749-016 Lisboa
- Portugal
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21
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Almeida I, Marquês J, Liu W, Niu Y, de Almeida R, Jin G, Viana A. Phospholipid/cholesterol/decanethiol mixtures for direct assembly of immunosensing interfaces. Colloids Surf B Biointerfaces 2015; 136:997-1003. [DOI: 10.1016/j.colsurfb.2015.10.048] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 10/13/2015] [Accepted: 10/29/2015] [Indexed: 12/20/2022]
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22
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Marquês JT, Cordeiro AM, Viana AS, Herrmann A, Marinho HS, de Almeida RFM. Formation and Properties of Membrane-Ordered Domains by Phytoceramide: Role of Sphingoid Base Hydroxylation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:9410-9421. [PMID: 26262576 DOI: 10.1021/acs.langmuir.5b02550] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Phytoceramide is the backbone of major sphingolipids in fungi and plants and is essential in several tissues of animal organisms, such as human skin. Its sphingoid base, phytosphingosine, differs from that usually found in mammals by the addition of a hydroxyl group to the 4-ene, which may be a crucial factor for the different properties of membrane microdomains among those organisms and tissues. Recently, sphingolipid hydroxylation in animal cells emerged as a key feature in several physiopathological processes. Hence, the study of the biophysical properties of phytosphingolipids is also relevant in that context since it helps us to understand the effects of sphingolipid hydroxylation. In this work, binary mixtures of N-stearoyl-phytoceramide (PhyCer) with palmitoyloleoylphosphatidylcholine (POPC) were studied. Steady-state and time-resolved fluorescence of membrane probes, X-ray diffraction, atomic force microscopy, and confocal microscopy were employed. As for other saturated ceramides, highly rigid gel domains start to form with just ∼5 mol % PhyCer at 24 °C. However, PhyCer gel-enriched domains in coexistence with POPC-enriched fluid present additional complexity since their properties (maximal order, shape, and thickness) change at specific POPC/PhyCer molar ratios, suggesting the formation of highly stable stoichiometric complexes with their own properties, distinct from both POPC and PhyCer. A POPC/PhyCer binary phase diagram, supported by the different experimental approaches employed, is proposed with complexes of 3:1 and 1:2 stoichiometries which are stable at least from ∼15 to ∼55 °C. Thus, it provides mechanisms for the in vivo formation of sphingolipid-enriched gel domains that may account for stable membrane compartments and diffusion barriers in eukaryotic cell membranes.
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Affiliation(s)
- Joaquim T Marquês
- Centro de Química e Bioquímica, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal
| | - André M Cordeiro
- Centro de Química e Bioquímica, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal
| | - Ana S Viana
- Centro de Química e Bioquímica, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal
| | - Andreas Herrmann
- Department of Biology, Molecular Biophysics, Humboldt University , Berlin, Germany
| | - H Susana Marinho
- Centro de Química e Bioquímica, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal
| | - Rodrigo F M de Almeida
- Centro de Química e Bioquímica, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal
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23
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Duarte AA, Botelho do Rego AM, Salerno M, Ribeiro PA, El Bari N, Bouchikhi B, Raposo M. DPPG Liposomes Adsorbed on Polymer Cushions: Effect of Roughness on Amount, Surface Composition and Topography. J Phys Chem B 2015; 119:8544-52. [PMID: 26076391 DOI: 10.1021/acs.jpcb.5b02384] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The adsorption of intact liposomes onto solid supports is a fundamental issue when preparing systems with encapsulated biological molecules. In this work, the adsorption kinetic of 1,2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt) liposomes onto cushions prepared from commom polyelectrolytes by the layer-by-layer technique was investigated with the main objective of finding the surface conditions leading to the adsorption of intact liposomes. For this purpose, different cushion surface roughnesses were obtained by changing the number of cushion bilayers. The adsorbed amount per unit area was measured through quartz crystal microbalance, surface morphology was characterized by atomic force microscopy, and the surface composition was assessed by X-ray photoelectron spectroscopy. The results show that (1) the amount of adsorbed lipids depends on the number of cushion bilayers, (2) the cushions are uniformly covered by the adsorbed lipids, and (3) the surface morphology of polymer cushions tunes liposome rupture and its adsorption kinetics. The fraction of ruptured liposomes, calculated from the measured amount of adsorbed lipids, is a function of surface roughness together with other surface morphology parameters, namely the dominating in-plane spatial feature size, the fractal dimension, and other textural features as well as amplitude and hybrid parameters.
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Affiliation(s)
- Andreia A Duarte
- †CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Ana M Botelho do Rego
- ‡Centro de Química-Física Molecular and IN, Complexo Interdisciplinar, Instituto Superior Técnico, University of Lisbon, 1049-001 Lisboa, Portugal
| | - Marco Salerno
- §Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova, Italy
| | - Paulo A Ribeiro
- †CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Nezha El Bari
- ∥Biotechnology Agroalimentary and Biomedical Analysis Group, Moulay Ismaïl University, Faculty of Sciences, Biology Department, B.P. 11201, Zitoune, Meknes, Morocco
| | | | - Maria Raposo
- †CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
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24
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Marquês JT, Antunes CA, Santos FC, de Almeida RF. Biomembrane Organization and Function. ADVANCES IN PLANAR LIPID BILAYERS AND LIPOSOMES 2015. [DOI: 10.1016/bs.adplan.2015.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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25
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Moiset G, López CA, Bartelds R, Syga L, Rijpkema E, Cukkemane A, Baldus M, Poolman B, Marrink SJ. Disaccharides Impact the Lateral Organization of Lipid Membranes. J Am Chem Soc 2014; 136:16167-75. [DOI: 10.1021/ja505476c] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Gemma Moiset
- Groningen
Biomolecular Sciences and Biotechnology Institute and Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Cesar A. López
- Groningen
Biomolecular Sciences and Biotechnology Institute and Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Rianne Bartelds
- Groningen
Biomolecular Sciences and Biotechnology Institute and Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Lukasz Syga
- Groningen
Biomolecular Sciences and Biotechnology Institute and Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Egon Rijpkema
- Groningen
Biomolecular Sciences and Biotechnology Institute and Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Abhishek Cukkemane
- NMR
Spectroscopy, Bijvoet Center for Biomolecular Research Department
of Chemistry, Faculty of Science, Utrecht University, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Marc Baldus
- NMR
Spectroscopy, Bijvoet Center for Biomolecular Research Department
of Chemistry, Faculty of Science, Utrecht University, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Bert Poolman
- Groningen
Biomolecular Sciences and Biotechnology Institute and Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Siewert J. Marrink
- Groningen
Biomolecular Sciences and Biotechnology Institute and Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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26
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Marquês JT, Viana AS, de Almeida RFM. A biomimetic platform to study the interactions of bioelectroactive molecules with lipid nanodomains. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:12627-12637. [PMID: 25267380 DOI: 10.1021/la503086a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this work, we developed a biomimetic platform where the study of membrane associated redox processes and high-resolution imaging of lipid nanodomains can be both performed, based on a new functional gold modification, l-cysteine self-assembled monolayer. This monolayer proved to be ideal for the preparation of defect-free planar supported lipid bilayers (SLBs) where nanodomains with height difference of ∼1.5 nm are clearly resolved by atomic force microscopy. Single and multicomponent lipid compositions were used, leading to the formation of different phases and domains mimicking the lateral organization of cellular membranes, and in all cases stable and continuous bilayers were obtained. These platforms were tested toward the interaction with bioelectroactive molecules, the antioxidant quercetin, and the hormone epinephrine. Despite the weak interaction detected between epinephrine and lipid bilayers, our biomimetic interface was able to sense the redox process of membrane-bound epinephrine, obtain its surface concentration (9.36 × 10(-11) mol/cm(2) for a fluid bilayer), and estimate a mole fraction membrane/water partition coefficient (Kp) from cyclic voltammetric measurements (1.13 × 10(4) for a fluid phase membrane). This Kp could be used to quantitatively describe the minute changes observed in the photophysical properties of epinephrine intrinsic fluorescence upon its interaction with liposome suspensions. Moreover, we showed that the lipid membrane stabilizes epinephrine structure, preventing its oxidation, which occurs in neutral aqueous solution, and that epinephrine partition and mobility in membranes depends on lipid phase, expanding our knowledge on hormone membrane interactions.
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Affiliation(s)
- Joaquim T Marquês
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa , Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal
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27
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Ngo AT, Jakubek ZJ, Lu Z, Joós B, Morris CE, Johnston LJ. Membrane order parameters for interdigitated lipid bilayers measured via polarized total-internal-reflection fluorescence microscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:2861-9. [PMID: 25073072 DOI: 10.1016/j.bbamem.2014.07.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 07/03/2014] [Accepted: 07/21/2014] [Indexed: 12/25/2022]
Abstract
Incorporating ethanol in lipid membranes leads to changes in bilayer structure, including the formation of an interdigitated phase. We have used polarized total-internal-reflection fluorescence microscopy (pTIRFM) to measure the order parameter for Texas Red DHPE incorporated in the ethanol-induced interdigitated phase (LβI) formed from ternary lipid mixtures comprising dioleoylphosphatidylcholine, cholesterol and egg sphingomyelin or dipalmitoylphosphatidylcholine. These lipid mixtures have 3 co-existing phases in the presence of ethanol: liquid-ordered, liquid-disordered and LβI. pTIRFM using Texas Red DHPE shows a reversal in fluorescence contrast between the LβI phase and the surrounding disordered phase with changes in the polarization angle. The contrast reversal is due to changes in the orientation of the dye, and provides a rapid method to identify the LβI phase. The measured order parameters for the LβI phase are consistent with a highly ordered membrane environment, similar to a gel phase. An acyl-chain labeled BODIPY-FL-PC was also tested for pTIRFM studies of ethanol-treated bilayers; however, this probe is less useful since the order parameters of the interdigitated phase are consistent with orientations that are close to random, either due to local membrane disorder or to a mixture of extended and looping conformations in which the fluorophore is localized in the polar headgroup region of the bilayer. In summary, we demonstrate that order parameter measurements via pTIRFM using Texas Red-DHPE can rapidly identify the interdigitated phase in supported bilayers. We anticipate that this technique will aid further research in the effects of alcohols and other additives on membranes.
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Affiliation(s)
- An T Ngo
- Measurement Science and Standards, National Research Council Canada, Ottawa, ON K1A 0R6, Canada; Department of Physics, University of Ottawa Ottawa, ON K1N 6N5, Canada
| | - Zygmunt J Jakubek
- Measurement Science and Standards, National Research Council Canada, Ottawa, ON K1A 0R6, Canada
| | - Zhengfang Lu
- Measurement Science and Standards, National Research Council Canada, Ottawa, ON K1A 0R6, Canada
| | - Béla Joós
- Department of Physics, University of Ottawa Ottawa, ON K1N 6N5, Canada
| | | | - Linda J Johnston
- Measurement Science and Standards, National Research Council Canada, Ottawa, ON K1A 0R6, Canada.
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28
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Lipid bilayers supported on bare and modified gold – Formation, characterization and relevance of lipid rafts. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2013.07.117] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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29
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Setiawan I, Blanchard GJ. Ethanol-induced perturbations to planar lipid bilayer structures. J Phys Chem B 2014; 118:537-46. [PMID: 24372563 DOI: 10.1021/jp410305m] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We report on the formation of planar lipid bilayer structures on mica where the bilayer contains the phosphocholine 1,2-dioleoyl-sn-phosphatidylcholine (DOPC), cholesterol, sphingomyelin and sulforhodamine-tagged-1,2-dioleoyl-sn-phosphatidylethanolamine (SR-DOPE). Phase separation is seen for the cholesterol domains within the bilayer structure, and exposure of this supported bilayer to controlled concentrations of ethanol reveals organizational changes on both the micrometer- and molecular-length scales. We report steady state fluorescence imaging, fluorescence lifetime imaging, and fluorescence anisotropy decay imaging for these bilayers. These data are complementary to existing information on the interactions of lipid bilayers with ethanol and point to subtle but important changes in the molecular-scale organization of these structures.
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Affiliation(s)
- Iwan Setiawan
- Department of Chemistry, Michigan State University , 578 S. Shaw Lane, East Lansing, Michigan 48824, United States
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30
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Kurniawan Y, Scholz C, Bothun GD. n-Butanol partitioning into phase-separated heterogeneous lipid monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:10817-10823. [PMID: 23888902 DOI: 10.1021/la400977h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Cellular adaptation to elevated alcohol concentration involves altering membrane lipid composition to counteract fluidization. However, few studies have examined the biophysical response of biologically relevant heterogeneous membranes. Lipid phase behavior, molecular packing, and elasticity have been examined by surface pressure-area (π-A) analysis in mixed monolayers composed of saturated dipalmitoylphosphatidylcholine (DPPC) and unsaturated dioleoylphosphatidylcholine (DOPC) as a function of DOPC and n-butanol concentration. n-Butanol partitioning into DPPC monolayers led to lipid expansion and increased elasticity. Greater lipid expansion occurred with increasing DOPC concentration, and a maximum was observed at equimolar DPPC:DOPC consistent with n-butanol partitioning between coexisting liquid expanded (LE, DOPC) phases and liquid condensed (LC, DPPC) domains. This led to distinct changes in the size and morphology of LC domains. In DOPC-rich monolayers the effect of n-butanol adsorption on π-A behavior was less pronounced due to DOPC tail kinking. These results point to the importance of lipid composition and phase coexistence on n-butanol partitioning and monolayer restructuring.
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Affiliation(s)
- Yogi Kurniawan
- Department of Chemical Engineering, University of Rhode Island, 16 Greenhouse Rd., Kingston, Rhode Island 02881, United States
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Stetter FWS, Hugel T. The nanomechanical properties of lipid membranes are significantly influenced by the presence of ethanol. Biophys J 2013; 104:1049-55. [PMID: 23473487 DOI: 10.1016/j.bpj.2013.01.021] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 12/16/2012] [Accepted: 01/14/2013] [Indexed: 12/27/2022] Open
Abstract
Ethanol has a profound impact on biological systems and is moreover used in various medical and nonmedical applications. Its interaction with the lipid part of biological membranes has been the subject of intensive studies, but surprisingly, to our knowledge, no study has examined the influence of ethanol on lipid bilayer nanomechanics. We performed atomic force microscopy-based measurements to assess the influence of ethanol on the nanomechanical properties of fluid supported lipid bilayers. Ethanol significantly reduces membrane stability, bilayer thickness, Young's modulus, area stretch modulus, and bending stiffness. Altogether, our data suggest that ethanol addition to supported lipid bilayers supports both the hydrophobic and the hydrophilic permeation pathways by a decrease of bilayer thickness and reduced stability, respectively.
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Affiliation(s)
- Frank W S Stetter
- IMETUM, Physik-Department, E22a, Technische Universität München, Munich, Germany
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Preparation of DOPC and DPPC Supported Planar Lipid Bilayers for Atomic Force Microscopy and Atomic Force Spectroscopy. Int J Mol Sci 2013; 14:3514-39. [PMID: 23389046 PMCID: PMC3588056 DOI: 10.3390/ijms14023514] [Citation(s) in RCA: 152] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 01/29/2013] [Accepted: 02/01/2013] [Indexed: 11/16/2022] Open
Abstract
Cell membranes are typically very complex, consisting of a multitude of different lipids and proteins. Supported lipid bilayers are widely used as model systems to study biological membranes. Atomic force microscopy and force spectroscopy techniques are nanoscale methods that are successfully used to study supported lipid bilayers. These methods, especially force spectroscopy, require the reliable preparation of supported lipid bilayers with extended coverage. The unreliability and a lack of a complete understanding of the vesicle fusion process though have held back progress in this promising field. We document here robust protocols for the formation of fluid phase DOPC and gel phase DPPC bilayers on mica. Insights into the most crucial experimental parameters and a comparison between DOPC and DPPC preparation are presented. Finally, we demonstrate force spectroscopy measurements on DOPC surfaces and measure rupture forces and bilayer depths that agree well with X-ray diffraction data. We also believe our approach to decomposing the force-distance curves into depth sub-components provides a more reliable method for characterising the depth of fluid phase lipid bilayers, particularly in comparison with typical image analysis approaches.
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Martin ML, Barceló-Coblijn G, de Almeida RFM, Noguera-Salvà MA, Terés S, Higuera M, Liebisch G, Schmitz G, Busquets X, Escribá PV. The role of membrane fatty acid remodeling in the antitumor mechanism of action of 2-hydroxyoleic acid. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:1405-13. [PMID: 23360770 DOI: 10.1016/j.bbamem.2013.01.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2012] [Revised: 12/15/2012] [Accepted: 01/17/2013] [Indexed: 01/08/2023]
Abstract
The synthetic fatty acid 2-hydroxyoleic acid (2OHOA) is a potent antitumor drug that we rationally designed to regulate the membrane lipid composition and structure. The lipid modifications caused by 2OHOA treatments induce important signaling changes that end up with cell death (Terés et al., 2012 [1]). One of these regulatory effects is restoration of sphingomyelin levels, which are markedly lower in cancer cells compared to normal cells (Barceló-Coblijn et al., 2011 [2]). In this study, we report another important regulatory effect of 2OHOA on cancer cell membrane composition: a large increase in 2OHOA levels, accounting for ~15% of the fatty acids present in membrane phospholipids, in human glioma (SF767 and U118) and lung cancer (A549) cells. Concomitantly, we observed marked reductions in oleic acid levels and inhibition of stearoyl-CoA desaturase. The impact of these changes on the biophysical properties of the lipid bilayer was evaluated in liposomes reconstituted from cancer cell membrane lipid extracts. Thus, 2OHOA increased the packing of ordered domains and decreased the global order of the membrane. The present results further support and extend the knowledge about the mechanism of action for 2OHOA, based on the regulation of the membrane lipid composition and structure and subsequent modulation of membrane protein-associated signaling.
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Affiliation(s)
- Maria Laura Martin
- Department of Biology, University of the Balearic Islands, Balearic Islands, Spain
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Bastos AEP, Marinho HS, Cordeiro AM, de Soure AM, de Almeida RFM. Biophysical properties of ergosterol-enriched lipid rafts in yeast and tools for their study: characterization of ergosterol/phosphatidylcholine membranes with three fluorescent membrane probes. Chem Phys Lipids 2012; 165:577-88. [PMID: 22705749 DOI: 10.1016/j.chemphyslip.2012.06.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 06/01/2012] [Accepted: 06/04/2012] [Indexed: 01/06/2023]
Abstract
In this work, binary mixtures of phospholipid/ergosterol (erg) were studied using three fluorescent membrane probes. The phospholipid was either saturated (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC) or monounsaturated (1-palmitoyl-2-dioleoyl-sn-glycero-3-phosphocholine, POPC) phosphatidylcholine, to evaluate the fluorescence properties of the probes in gel, liquid ordered (l(o)) and liquid disordered (l(d)) phases. The probes have been used previously to study cholesterol-enriched domains, but their photophysical properties in erg-enriched membranes have not been characterized. N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine (NBD-DPPE) presents modest blue-shifts upon erg addition, and the changes in the fluorescence lifetime are mainly due to differences in the efficiency of its fluorescence dynamic self-quenching. However, the steady-state fluorescence anisotropy of NBD-DPPE presents well-defined values in each lipid phase. N-(lissamine rhodamine B sulfonyl)-1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (Rhod-DOPE) presents a close to random distribution in erg-rich membranes. There are no appreciable spectral shifts and the steady-state fluorescence anisotropy presents complex behavior, as a result of different photophysical processes. The probe is mostly useful to label l(d) domains in yeast membranes. 4-(2-(6-(Dibutylamino)-2-naphthalenyl)ethenyl)-1-(3-sulfopropyl)-pyridinium (di-4-ANEPPS) is an electrochromic dye with excitation spectra largely insensitive to the presence of erg, but presenting a strong blue-shift of its emission with increasing concentrations of this sterol. Its partition coefficient is favorable to l(o) domains in POPC/erg mixtures. Although the fluorescence properties of di-4-ANEPPS are less sensitive to erg than to chol, in both cases the fluorescence lifetime responds monotonically to sterol mole fraction, becoming significantly longer in the presence of sterol as compared to pure POPC or DPPC bilayers. The probe displays a unique sensitivity to sterol-lipid interaction due to the influence of hydration and H-bonding patterns at the membrane/water interface on its fluorescence properties. This makes di-4-ANEPPS (and possibly similar probes) potentially useful in the study of erg-enriched domains in more complex lipid mixtures and in the membranes of living yeast cells.
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Affiliation(s)
- André E P Bastos
- Centro de Química e Bioquímica, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
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Kurniawan Y, Venkataramanan KP, Scholz C, Bothun GD. n-Butanol Partitioning and Phase Behavior in DPPC/DOPC Membranes. J Phys Chem B 2012; 116:5919-24. [DOI: 10.1021/jp301340k] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yogi Kurniawan
- Department of Chemical Engineering, University of Rhode Island, 16 Greenhouse Rd, Kingston,
Rhode Island 02881, United States
| | - Keerthi P. Venkataramanan
- Biotechnology Science and Engineering
program, University of Alabama in Huntsville, 301 Sparkman Dr., Huntsville, Alabama 35899, United States
| | - Carmen Scholz
- Department of Chemistry, University of Alabama in Huntsville, 301 Sparkman Dr.,
Huntsville, Alabama 35899, United States
| | - Geoffrey D. Bothun
- Department of Chemical Engineering, University of Rhode Island, 16 Greenhouse Rd, Kingston,
Rhode Island 02881, United States
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Okamoto Y, Tsuzuki K, Iwasa S, Ishikawa R, Sandhu A, Tero R. Fabrication of Supported Lipid Bilayer on Graphene Oxide. ACTA ACUST UNITED AC 2012. [DOI: 10.1088/1742-6596/352/1/012017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Vanegas JM, Contreras MF, Faller R, Longo ML. Role of unsaturated lipid and ergosterol in ethanol tolerance of model yeast biomembranes. Biophys J 2012; 102:507-16. [PMID: 22325273 DOI: 10.1016/j.bpj.2011.12.038] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 12/21/2011] [Accepted: 12/23/2011] [Indexed: 11/27/2022] Open
Abstract
We present a combined atomic force microscopy and fluorescence microscopy study of the behavior of a ternary supported lipid bilayer system containing a saturated lipid (DPPC), an unsaturated lipid (DOPC), and ergosterol in the presence of high ethanol (20 vol %). We find that the fluorescent probe Texas Red DHPE preferentially partitions into the ethanol-induced interdigitated phase, which allows the use of fluorescence imaging to investigate the phase behavior of the system. Atomic force microscopy and fluorescence images of samples with the same lipid mixture show good agreement in sample morphology and area fractions of the observed phases. Using area fractions obtained from fluorescence images over a broad range of compositions, we constructed a phase diagram of the DPPC/DOPC/ergosterol system at 20 vol % ethanol. The phase diagram clearly shows that increasing unsaturated lipid and/or ergosterol protects the membrane by preventing the formation of the interdigitated phase. This result supports the hypothesis that yeast cells increase ergosterol and unsaturated lipid content to prevent interdigitation and maintain an optimal membrane thickness as ethanol concentration increases during anaerobic fermentations. Changes in plasma membrane composition provide an important survival factor for yeast cells to deter ethanol toxicity.
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Affiliation(s)
- Juan M Vanegas
- Biophysics Graduate Group, College of Biological Sciences, University of California, Davis, California, USA
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Gözen I, Jesorka A. Instrumental Methods to Characterize Molecular Phospholipid Films on Solid Supports. Anal Chem 2012; 84:822-38. [DOI: 10.1021/ac203126f] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Irep Gözen
- Department of Chemical and Biological
Engineering, Chalmers University of Technology, Kemivägen 10, 41296 Göteborg, Sweden
| | - Aldo Jesorka
- Department of Chemical and Biological
Engineering, Chalmers University of Technology, Kemivägen 10, 41296 Göteborg, Sweden
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Bastos AE, Scolari S, Stöckl M, de Almeida RF. Applications of Fluorescence Lifetime Spectroscopy and Imaging to Lipid Domains In Vivo. Methods Enzymol 2012; 504:57-81. [DOI: 10.1016/b978-0-12-391857-4.00003-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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40
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Amado E, Kressler J. Interactions of amphiphilic block copolymers with lipid model membranes. Curr Opin Colloid Interface Sci 2011. [DOI: 10.1016/j.cocis.2011.07.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Dolganiuc A. Role of lipid rafts in liver health and disease. World J Gastroenterol 2011; 17:2520-35. [PMID: 21633657 PMCID: PMC3103810 DOI: 10.3748/wjg.v17.i20.2520] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 02/24/2011] [Accepted: 03/03/2011] [Indexed: 02/06/2023] Open
Abstract
Liver diseases are an increasingly common cause of morbidity and mortality; new approaches for investigation of mechanisms of liver diseases and identification of therapeutic targets are emergent. Lipid rafts (LRs) are specialized domains of cellular membranes that are enriched in saturated lipids; they are small, mobile, and are key components of cellular architecture, protein partition to cellular membranes, and signaling events. LRs have been identified in the membranes of all liver cells, parenchymal and non-parenchymal; more importantly, LRs are active participants in multiple physiological and pathological conditions in individual types of liver cells. This article aims to review experimental-based evidence with regard to LRs in the liver, from the perspective of the liver as a whole organ composed of a multitude of cell types. We have gathered up-to-date information related to the role of LRs in individual types of liver cells, in liver health and diseases, and identified the possibilities of LR-dependent therapeutic targets in liver diseases.
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