1
|
Pašalić L, Liu Q, Vukosav P, Mišić Radić T, Azziz A, Majdinasab M, Edely M, de la Chapelle ML, Bakarić D. The presence of uncoated gold nanoparticle aggregates may alter the phase of phosphatidylcholine lipid as evidenced by vibrational spectroscopies. J Liposome Res 2024; 34:113-123. [PMID: 37493091 DOI: 10.1080/08982104.2023.2239905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 07/18/2023] [Indexed: 07/27/2023]
Abstract
Spherical structures built from uni- and multilamellar lipid bilayers (LUV and MLV) are nowadays considered not just as nanocarriers of various kinds of therapeutics, but also as the vehicles that, when coupled with gold (Au) nanoparticles (NPs), can also serve as a tool for imaging and discriminating healthy and diseased tissues. Since the presence of Au NPs or their aggregates may affect the properties of the drug delivery vehicle, we investigated how the shape and position of Au NP aggregates adsorbed on the surface of MLV affect the arrangement and conformation of lipid molecules. By preparing MLVs constituted from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in the presence of uncoated Au NP aggregates found i) both within liposome core and on the surface of the outer lipid bilayer, or ii) adsorbed on the outer lipid bilayer surface only, we demonstrated the maintenance of lipid bilayer integrity by microscopic techniques (cryo-TEM, and AFM). The employment of SERS and FTIR-ATR techniques enabled us not only to elucidate the lipid interaction pattern and their orientation in regards to Au NP aggregates but also unequivocally confirmed the impact of Au NP aggregates on the persistence/breaking of van der Waals interactions between hydrocarbon chains of DPPC.
Collapse
Affiliation(s)
- Lea Pašalić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Zagreb, Croatia
| | - Qiqian Liu
- The Institute of Molecules and Materials of Le Mans, University of Le Mans, Le Mans, France
| | - Petra Vukosav
- Division for Marine and Environmental Research, Ruđer Bošković Institute, Zagreb, Croatia
| | - Tea Mišić Radić
- Division for Marine and Environmental Research, Ruđer Bošković Institute, Zagreb, Croatia
| | - Aicha Azziz
- The Institute of Molecules and Materials of Le Mans, University of Le Mans, Le Mans, France
| | - Marjan Majdinasab
- The Institute of Molecules and Materials of Le Mans, University of Le Mans, Le Mans, France
| | - Mathieu Edely
- The Institute of Molecules and Materials of Le Mans, University of Le Mans, Le Mans, France
| | | | - Danijela Bakarić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Zagreb, Croatia
| |
Collapse
|
2
|
Mielke S, Sorkin R, Klein J. Effect of cholesterol on the mechanical stability of gel-phase phospholipid bilayers studied by AFM force spectroscopy. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2023; 46:77. [PMID: 37672138 DOI: 10.1140/epje/s10189-023-00338-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 08/24/2023] [Indexed: 09/07/2023]
Abstract
The remarkably low sliding friction of articular cartilage in the major joints such as hips and knees, which is crucial for its homeostasis and joint health, has been attributed to lipid bilayers forming lubricious boundary layers at its surface. The robustness of such layers, and thus their lubrication efficiency at joint pressures, depends on the lipids forming them, including cholesterol which is a ubiquitous component, and which may act to strengthen of weaken the bilayer. In this work, a systematic study using an atomic force microscope (AFM) was carried out to understand the effect of cholesterol on the nanomechanical stability of two saturated phospholipids, DSPC (1,2-distearoyl-sn-glycero-3-phosphatidlycholine) and DPPC (1,2-dipalmitoyl-sn-glycero- phosphatidylcholine), that differ in acyl chain lengths. Measurements were carried out both in water and in phosphate buffer solution (PBS). The nanomechanical stability of the lipid bilayers was quantitatively evaluated by measuring the breakthrough force needed to puncture the bilayer by the AFM tip. The molar fractions of cholesterol incorporated in the bilayers were 10% and 40%. We found that for both DSPC and DPPC, cholesterol significantly decreases the mechanical stability of the bilayers in solid-ordered (SO) phase. In accordance with the literature, the strengthening effect of salt on the lipid bilayers was also observed. For DPPC with 10 mol % cholesterol, the effect of tip properties and the experimental procedure parameters on the breakthrough forces were also studied. Tip radius (2-42 nm), material (Si, Si3N4, Au) and loading rate (40-1000 nm/s) were varied systematically. The values of the breakthrough forces measured were not significantly affected by any of these parameters, showing that the weakening effect of cholesterol does not result from such changes in experimental conditions. As we have previously demonstrated that mechanical robustness improves the tribological performance of lipid layers, this study helps to shed light on the mechanism of physiological lubrication. Nanoindentation of SDPC bilayers.
Collapse
Affiliation(s)
- Salomé Mielke
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, 76100, Rehovot, Israel
| | - Raya Sorkin
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, 6997801, Tel Aviv, Israel.
| | - Jacob Klein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, 76100, Rehovot, Israel.
| |
Collapse
|
3
|
Pal VK, Roy S. Cooperative Calcium Phosphate Deposition on Collagen-Inspired Short Peptide Nanofibers for Application in Bone Tissue Engineering. Biomacromolecules 2023; 24:807-824. [PMID: 36649490 DOI: 10.1021/acs.biomac.2c01262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In recent years, immense attention has been devoted over the production of osteoinductive materials. To this direction, collagen has a dominant role in developing hard tissues and plays a crucial role in the biomineralization of these tissues. Here, we demonstrated for the first time the potential of the shortest molecular pentapeptide domain inspired from collagen toward mineralizing hydroxyapatite on peptide fibers to develop bone-filling material. Our simplistic approach adapted the easy and facile route of introducing the metal ions onto the peptide nanofibers, displaying adsorbed glutamate onto the surface. This negatively charged surface further induces the nucleation of the crystalline growth of hydroxyapatite. Interestingly, nucleation and growth of the hydroxyapatite crystals lead to the formation of a self-supporting hydrogel to construct a suitable interface for cellular interactions. Furthermore, microscopic and spectroscopic investigations revealed the crystalline growth of the hydroxyapatite onto peptide fibers. The physical properties were also influenced by this crystalline deposition, as evident from the hierarchical organization leading to hydrogels with enhanced mechanical stiffness and improved thermal stability of the scaffold. Furthermore, the mineralized peptide fibers were highly compatible with osteoblast cells and showed increased cellular biomarkers production, which further reinforced the potential application toward effectively fabricating the grafts for bone tissue engineering.
Collapse
Affiliation(s)
- Vijay Kumar Pal
- Institute of Nano Science and Technology, Knowledge City, Sector 81, Mohali140306, India
| | - Sangita Roy
- Institute of Nano Science and Technology, Knowledge City, Sector 81, Mohali140306, India
| |
Collapse
|
4
|
Havlíková M, Jugl A, Kadlec M, Smilek J, Chang CH, Pekař M, Mravec F. Catanionic vesicles and their complexes with hyaluronan – A way how to tailor physicochemical properties via ionic strength. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2022.121089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
5
|
Maleš P, Butumović M, Erceg I, Brkljača Z, Bakarić D. Influence of DPPE surface undulations on melting temperature determination: UV/Vis spectroscopic and MD study. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184072. [PMID: 36216096 DOI: 10.1016/j.bbamem.2022.184072] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 09/09/2022] [Accepted: 10/04/2022] [Indexed: 11/13/2022]
Abstract
One of the most distinguished quantities that describes lipid main phase transition, i.e. the transition from the gel (Lβ(')) to the fluid (Lα) phase, is its melting temperature (Tm). Because melting is accompanied by a large change in enthalpy the, Lβ(') → Lα transition can be monitored by various calorimetric, structural and spectroscopic techniques and Tm should be the same regardless of the metric monitored or the technique employed. However, in the case of DPPE multilamellar aggregates there is a small but systematic deviation of Tm values determined by DSC and FTIR spectroscopy. The aim of this paper is to explain this discrepancy by combined UV/Vis spectroscopic and MD computational approach. Multivariate analysis performed on temperature-dependent UV/Vis spectra of DPPE suspensions demonstrated that at 55 ± 1 °C certain phenomenon causes a small but detectable change in suspension turbidity, whereas a dominant change in the latter is registered at 63.2 ± 0.4 °C that coincides with Tm value determined from DSC curve. If this effect should be ignored, the overall data give Tm value the same as FTIR spectra data (61.0 ± 0.4 °C). As the classical MD simulations suggest that about 10° below Tm certain undulations appear at the surface of DPPE bilayers, we concluded that certain discontinuities in curvature fluctuations arise at reported temperature which are to some extent coupled with lipid melting. Ultimately, such events and the associated changes in curvature affect Tm value measured by different techniques.
Collapse
Affiliation(s)
- Petra Maleš
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Marija Butumović
- Division of Analytical Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000 Zagreb, Croatia
| | - Ina Erceg
- Division for Physical Chemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Zlatko Brkljača
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
| | - Danijela Bakarić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
| |
Collapse
|
6
|
Hamada N, Longo ML. Charged hybrid block copolymer-lipid-cholesterol vesicles: pH, ionic environment, and composition dependence of phase transitions. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:184026. [PMID: 35952852 DOI: 10.1016/j.bbamem.2022.184026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/23/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
The impacts of pH, salt concentration (expressed as Debye length), and composition on the phase behavior of hybrid block copolymer-lipid-cholesterol bilayers incorporating carboxyl-terminated poly(butadiene)-block-poly(ethylene oxide) copolymer (PBdPEO1800(-)) or/and non-carboxyl-terminated PBdPEO (PBdPEO1800 or/and PBdPEO950), egg sphingomyelin (egg SM), and cholesterol were examined using fluorescence spectroscopy of laurdan. Laurdan emission spectra were decomposed into three lognormal curves as functions of energy. The ratio of the area of the mid-energy peak to the sum of the areas of all three peaks was evaluated as vesicles were cooled, yielding temperature breakpoint values (Tbreak) expected to be within the range of the phase transition temperature. Tbreak values displayed dependence on pH, Debye length, and vesicle composition consistent with an electrostatic repulsion contribution to vesicle phase behavior. Increased pH and Debye length, for which a greater dissociated fraction of PBdPEO1800(-) and a greater energy of electrostatic repulsion would be expected, resulted in Tbreak values as much as 10 °C less than at low pH or short Debye lengths. Additionally, at Debye lengths comparable to those at physiologically relevant ionic strength, Tbreak at pH 5.9 was observed to be slightly higher than at pH 7.0 for vesicles containing 50 mol% PBdPEO1800(-). Electrostatic effects observed for hybrid vesicles incorporating significant amounts of carboxyl-terminated polymer may have the ability to drive phase separation in response to pH drops-such as those observed after endocytosis-in physiologically relevant conditions, suggesting the utility of such materials for drug delivery.
Collapse
Affiliation(s)
- Naomi Hamada
- Department of Chemical Engineering, University of California Davis, Davis, CA 95616, United States
| | - Marjorie L Longo
- Department of Chemical Engineering, University of California Davis, Davis, CA 95616, United States.
| |
Collapse
|
7
|
Hossain SI, Seppelt M, Nguyen N, Stokes C, Deplazes E. The role of ion-lipid interactions and lipid packing in transient defects caused by phenolic compounds. Biophys J 2022; 121:3520-3532. [PMID: 35932150 PMCID: PMC9515000 DOI: 10.1016/j.bpj.2022.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 07/19/2022] [Accepted: 08/03/2022] [Indexed: 11/16/2022] Open
Abstract
The transient disruption of membranes for the passive permeation of ions or small molecules is a complex process relevant to understanding physiological processes and biotechnology applications. Phenolic compounds are widely studied for their antioxidant and antimicrobial properties, and some of these activities are based on the interactions of the phenolic compound with membranes. Ions are ubiquitous in cells and are known to alter the structure of phospholipid bilayers. Yet, ion-lipid interactions are usually ignored when studying the membrane-altering properties of phenolic compounds. This study aims to assess the role of Ca2+ ions on the membrane-disrupting activity of two phenolic acids and to highlight the role of local changes in lipid packing in forming transient defects or pores. Results from tethered bilayer lipid membrane electrical impedance spectroscopy experiments showed that Ca2+ significantly reduces membrane disruption by caffeic acid methyl ester and caffeic acid. As phenolic acids are known metal chelators, we used UV-vis and fluorescence spectroscopy to exclude the possibility that Ca2+ interferes with membrane disruption by binding to the phenolic compound and subsequently preventing membrane binding. Molecular dynamics simulations showed that Ca2+ but not caffeic acid methyl ester or caffeic acid increases lipid packing in POPC bilayers. The combined data confirm that Ca2+ reduces the membrane-disrupting activity of the phenolic compounds, and that Ca2+-induced changes to lipid packing govern this effect. We discuss our data in the context of ion-induced pores and transient defects and how lipid packing affects membrane disruption by small molecules.
Collapse
Affiliation(s)
- Sheikh I Hossain
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
| | - Mathilda Seppelt
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
| | - Natalie Nguyen
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
| | - Chelsea Stokes
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
| | - Evelyne Deplazes
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia.
| |
Collapse
|
8
|
Abou Karam P, Rosenhek‐Goldian I, Ziv T, Ben Ami Pilo H, Azuri I, Rivkin A, Kiper E, Rotkopf R, Cohen SR, Torrecilhas AC, Avinoam O, Rojas A, Morandi MI, Regev‐Rudzki N. Malaria parasites release vesicle subpopulations with signatures of different destinations. EMBO Rep 2022; 23:e54755. [PMID: 35642585 PMCID: PMC9253735 DOI: 10.15252/embr.202254755] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/02/2022] [Accepted: 05/11/2022] [Indexed: 11/09/2022] Open
Abstract
Malaria is the most serious mosquito-borne parasitic disease, caused mainly by the intracellular parasite Plasmodium falciparum. The parasite invades human red blood cells and releases extracellular vesicles (EVs) to alter its host responses. It becomes clear that EVs are generally composed of sub-populations. Seeking to identify EV subpopulations, we subject malaria-derived EVs to size-separation analysis, using asymmetric flow field-flow fractionation. Multi-technique analysis reveals surprising characteristics: we identify two distinct EV subpopulations differing in size and protein content. Small EVs are enriched in complement-system proteins and large EVs in proteasome subunits. We then measure the membrane fusion abilities of each subpopulation with three types of host cellular membranes: plasma, late and early endosome. Remarkably, small EVs fuse to early endosome liposomes at significantly greater levels than large EVs. Atomic force microscope imaging combined with machine-learning methods further emphasizes the difference in biophysical properties between the two subpopulations. These results shed light on the sophisticated mechanism by which malaria parasites utilize EV subpopulations as a communication tool to target different cellular destinations or host systems.
Collapse
Affiliation(s)
- Paula Abou Karam
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | | | - Tamar Ziv
- Smoler Proteomics CenterDepartment of BiologyTechnion – Israel Institute of TechnologyHaifaIsrael
| | - Hila Ben Ami Pilo
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Ido Azuri
- Bioinformatics UnitLife Sciences Core FacilitiesWeizmann Institute of ScienceRehovotIsrael
| | - Anna Rivkin
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Edo Kiper
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Ron Rotkopf
- Bioinformatics UnitLife Sciences Core FacilitiesWeizmann Institute of ScienceRehovotIsrael
| | - Sidney R Cohen
- Department of Chemical Research SupportWeizmann Institute of ScienceRehovotIsrael
| | | | - Ori Avinoam
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Alicia Rojas
- Laboratory of HelminthologyFaculty of MicrobiologyUniversity of Costa RicaSan JoséCosta Rica
| | - Mattia I Morandi
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Neta Regev‐Rudzki
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| |
Collapse
|
9
|
Liu B, Zhang J, Gou J, Zhang Y, He H, Yin T, Zheng Z, Tang X. The effects of intermolecular interactions on the stability and in vitro drug release of daunorubicin/cytarabine co-loaded liposome. Colloids Surf B Biointerfaces 2022; 217:112673. [PMID: 35780612 DOI: 10.1016/j.colsurfb.2022.112673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 06/18/2022] [Accepted: 06/27/2022] [Indexed: 11/30/2022]
Abstract
Various studies were performed on the intermolecular interactions of daunorubicin (DNR) and cytarabine (Ara-C) co-loaded liposome to predict and elucidate its stability and in vitro drug release behavior. Langmuir monolayer and spectroscopy studies showed interactions between its components. The Langmuir monolayer study and blank liposomes stability study illustrated that interactions between lipids could affect their stability, and the DSPC/DSPG/Chol (7/2/1, mol%) mixed system tended to be thermodynamically and physicochemically stable. The interactions between daunorubicin and copper ions were then investigated by ultraviolet-visible (UV-vis) electronic absorption spectroscopy and circular dichroism (CD) spectroscopy, which revealed that the DNR-Cu complex was composed of daunorubicin and copper ions at a molar ratio of 1:1 or 1:2, and its solubility was related to the acidity of the solution. In vitro release experiment of liposomes with different copper gluconate contents illustrated that the interactions between drugs and copper ions were conducive to the retention and synergetic release of drugs. The stability and release studies of the DSPC/DSPG/Chol (7/2/1, mol%) co-loaded liposome illustrated that it had good storage and plasma stability, and the release behaviors of drugs were pH-related, i.e., drugs could be released faster under acidic condition. These studies indicated that intermolecular interactions could affect the stability and release behavior of the liposome, and a certain ratio of components could be conducive to its stability and synergistic release of drugs.
Collapse
Affiliation(s)
- Boyuan Liu
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China
| | - Jiaoyang Zhang
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China
| | - Jingxin Gou
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China
| | - Yu Zhang
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China
| | - Haibing He
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China
| | - Tian Yin
- School of Functional Food and Wine, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China
| | - Zhonghui Zheng
- Shandong Xinhua Pharmaceutical Co., Ltd., Zibo 255086, Shandong, China
| | - Xing Tang
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China.
| |
Collapse
|
10
|
Maleš P, Brkljača Z, Domazet Jurašin D, Bakarić D. New spirit of an old technique: Characterization of lipid phase transitions via UV/Vis spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 272:121013. [PMID: 35176647 DOI: 10.1016/j.saa.2022.121013] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/26/2022] [Accepted: 02/04/2022] [Indexed: 06/14/2023]
Abstract
One of the advantages of investigating lipid phase transitions by thermoanalytical techniques such as DSC is manifested in the proportionality of the signal strength on a DSC curve, attributed to a particular thermotropic event, and its cooperativity degree. Accordingly, the pretransition of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) is less noticeable than its main phase transition; as a matter of fact, when DSC measurements are performed at low heating rate, such low-cooperativity phase transition could go (almost) unnoticed. The aim of this work is to present temperature-dependent UV/Vis spectroscopy, based on a temperature-dependent change in DPPC suspension turbidity, as a technique applicable for determination of lipid phase transition temperatures. Multivariate analyzes of the acquired UV/Vis spectra show that phase transitions of the low-cooperativity degree, such as pretransitions, can be identified with the same certainty as transitions of a high-cooperativity degree.
Collapse
Affiliation(s)
- Petra Maleš
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia
| | - Zlatko Brkljača
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia
| | - Darija Domazet Jurašin
- Division for Physical Chemistry, Ruđer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia
| | - Danijela Bakarić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia.
| |
Collapse
|
11
|
Synthetic methods of lipid-coated mesoporous silica nanoparticles as drug carriers. Biointerphases 2022; 17:020801. [PMID: 35232023 DOI: 10.1116/6.0001688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The lipid-coated mesoporous silica nanoparticles (LMSNs) that can synergistically harness the advantages and mitigate the disadvantages of the liposomes and MSNs are considered potential drug carriers. So far, several methods have been developed to prepare LMSNs, including vesicle fusion, thin-film hydration, and solvent exchange. Despite their wide application in LMSN preparation, these methods are short of detailed elaboration and comparison, which hinders their further development. In this review, for the first time, the three methods are systematically summarized, including their mechanisms, influence factors, advantages, and limitations. Although these methods are all based on lipid self-assembly, there is still a difference between them. In order to efficiently prepare LMSNs, we proposed that a suitable method should be selected based on the actual situation. It is conceivable that the elaboration and comparison in this review will make these methods easy to be understood and provide guidance for the design of LMSNs as drug carriers.
Collapse
|
12
|
Fonseka NM, Arce FT, Christie HS, Aspinwall CA, Saavedra SS. Nanomechanical Properties of Artificial Lipid Bilayers Composed of Fluid and Polymerizable Lipids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:100-111. [PMID: 34968052 DOI: 10.1021/acs.langmuir.1c02098] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Polymerization enhances the stability of a planar supported lipid bilayer (PSLB) but it also changes its chemical and mechanical properties, attenuates lipid diffusion, and may affect the activity of integral membrane proteins. Mixed bilayers composed of fluid lipids and poly(lipids) may provide an appropriate combination of polymeric stability coupled with the fluidity and elasticity needed to maintain the bioactivity of reconstituted receptors. Previously (Langmuir, 2019, 35, 12483-12491) we showed that binary mixtures of the polymerizable lipid bis-SorbPC and the fluid lipid DPhPC form phase-segregated PSLBs composed of nanoscale fluid and poly(lipid) domains. Here we used atomic force microscopy (AFM) to compare the nanoscale mechanical properties of these binary PSLBs with single-component PSLBs. The elastic (Young's) modulus, area compressibility modulus, and bending modulus of bis-SorbPC PSLBs increased upon polymerization. Before polymerization, breakthrough events at forces below 5 nN were observed, but after polymerization, the AFM tip could not penetrate the PSLB up to an applied force of 20 nN. These results are attributed to the polymeric network in poly(bis-SorbPC), which increases the bilayer stiffness and resists compression and bending. In binary DPhPC/poly(bis-SorbPC) PSLBs, the DPhPC domains are less stiff, more compressible, and are less resistant to rupture and bending compared to pure DPhPC bilayers. These differences are attributed to bis-SorbPC monomers and oligomers present in DPhPC domains that disrupt the packing of DPhPC molecules. In contrast, the poly(bis-SorbPC) domains are stiffer and less compressible relative to pure PSLBs; this difference is attributed to DPhPC filling the nm-scale pores in the polymerized domains that are created during bis-SorbPC polymerization. Thus, incomplete phase segregation increases the stability of poly(bis-SorbPC) but has the opposite, detrimental effect for DPhPC. Overall, these results provide guidance for the design of partially polymerized bilayers for technological uses.
Collapse
Affiliation(s)
- N Malithi Fonseka
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Fernando Teran Arce
- Department of Medicine, University of Arizona, Tucson, Arizona 85721, United States
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Hamish S Christie
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Craig A Aspinwall
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
- BIO5 Institute and Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - S Scott Saavedra
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
- BIO5 Institute and Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| |
Collapse
|
13
|
Vázquez RF, Ovalle-García E, Antillón A, Ortega-Blake I, Muñoz-Garay C, Maté SM. Formation and Nanoscale Characterization of Asymmetric Supported Lipid Bilayers Containing Raft-Like Domains. Methods Mol Biol 2022; 2402:243-256. [PMID: 34854049 DOI: 10.1007/978-1-0716-1843-1_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The development of new strategies for achieving stable asymmetric membrane models has turned interleaflet lipid asymmetry into a topic of major interest. Cyclodextrin-mediated lipid exchange constitutes a simple and versatile method for preparing asymmetric membrane models without the need for sophisticated equipment. Here we describe a protocol for preparing asymmetric supported lipid bilayers mimicking membrane rafts by cyclodextrin-mediated lipid exchange and the main guidelines for obtaining structural information and quantitative measures of their mechanical properties using Atomic force microscopy and Force spectroscopy; two powerful techniques that allow membrane characterization at the nanoscale.
Collapse
Affiliation(s)
- Romina F Vázquez
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CCT-La Plata, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina.
- Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina.
| | - Erasmo Ovalle-García
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Armando Antillón
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Iván Ortega-Blake
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Carlos Muñoz-Garay
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Sabina M Maté
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CCT-La Plata, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina.
| |
Collapse
|
14
|
Wieser V, Mears LLE, Barker RD, Cheng HW, Valtiner M. Hydration Forces Dominate Surface Charge Dependent Lipid Bilayer Interactions under Physiological Conditions. J Phys Chem Lett 2021; 12:9248-9252. [PMID: 34533315 PMCID: PMC8488952 DOI: 10.1021/acs.jpclett.1c02572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Indexed: 06/13/2023]
Abstract
Lipid bilayer interactions are essential to a vast range of biological functions, such as intracellular transport mechanisms. Surface charging mediated by concentration dependent ion adsorption and desorption on lipid headgroups alters electric double layers as well as van der Waals and steric hydration forces of interacting bilayers. Here, we directly measure bilayer interactions during charge modulation in a symmetrically polarized electrochemical three-mirror interferometer surface forces apparatus. We quantify polarization and concentration dependent hydration and electric double layer forces due to cation adsorption/desorption. Our results demonstrate that exponential hydration layer interactions effectively describe surface potential dependent surface forces due to cation adsorption at high salt concentrations. Hence, electric double layers of lipid bilayers are exclusively dominated by inner Helmholtz charge regulation under physiological conditions. These results are important for rationalizing bilayer behavior under physiological conditions, where charge and concentration modulation may act as biological triggers for function and signaling.
Collapse
Affiliation(s)
- Valentina Wieser
- Institute
for Applied Physics, Vienna University of
Technology, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Laura L. E. Mears
- Institute
for Applied Physics, Vienna University of
Technology, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Robert D. Barker
- School
of Physical Sciences, University of Kent, Canterbury CT2 7NZ, United Kingdom
| | - Hsiu-Wei Cheng
- Institute
for Applied Physics, Vienna University of
Technology, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Markus Valtiner
- Institute
for Applied Physics, Vienna University of
Technology, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| |
Collapse
|
15
|
Wood MH, Milan DC, Nichols RJ, Casford MTL, Horswell SL. A quantitative determination of lipid bilayer deposition efficiency using AFM. RSC Adv 2021; 11:19768-19778. [PMID: 35479201 PMCID: PMC9033767 DOI: 10.1039/d1ra01920a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/26/2021] [Indexed: 12/14/2022] Open
Abstract
The efficacy of a number of different methods for depositing a dimyristoylphosphatidylcholine (DMPC) lipid bilayer or DMPC–cholesterol (3 : 1) mixed bilayer onto a silicon substrate has been investigated in a quantitative manner using atomic force microscopy (AFM) image analysis to extract surface coverage. Complementary AFM-IR measurements were used to confirm the presence of the lipids. For the Langmuir–Blodgett/Schaefer deposition method at temperatures below the chain-melting transition temperature (Tm), a large number of bilayer defects resulted when DMPC was deposited from a water subphase. Addition of calcium ions to the trough led to smaller, more frequent defects, whereas addition of cholesterol to the lipid mixture led to a vast improvement in bilayer coverage. Poor coverage was achieved for deposition at temperatures above Tm. Formation of the deposited bilayer from vesicle fusion proved a more reliable method for all systems, with formation of near-complete bilayers within 60 seconds at temperatures above Tm, although this method led to a higher probability of multilayer formation and rougher bilayer surfaces. The efficacy of different methods for depositing a DMPC or mixed DMPC–cholesterol (3 : 1) lipid bilayer onto a silicon substrate has been investigated in a quantitative manner using atomic force microscopy image analysis to extract surface coverage.![]()
Collapse
Affiliation(s)
- Mary H Wood
- School of Chemistry, University of Birmingham Birmingham B15 2TT UK
| | - David C Milan
- Department of Chemistry, University of Liverpool Liverpool L69 7ZD UK
| | - Richard J Nichols
- Department of Chemistry, University of Liverpool Liverpool L69 7ZD UK
| | - Michael T L Casford
- Department of Chemistry, University of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Sarah L Horswell
- School of Chemistry, University of Birmingham Birmingham B15 2TT UK
| |
Collapse
|
16
|
Galluzzi M, Zhang B, Zhang H, Wang L, Lin Y, Yu XF, Chu Z, Li J. Unveiling a Hidden Event in Fluorescence Correlative Microscopy by AFM Nanomechanical Analysis. Front Mol Biosci 2021; 8:669361. [PMID: 34026842 PMCID: PMC8136518 DOI: 10.3389/fmolb.2021.669361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 04/22/2021] [Indexed: 11/18/2022] Open
Abstract
Fluorescent imaging combined with atomic force microscopy (AFM), namely AFM-fluorescence correlative microscopy, is a popular technology in life science. However, the influence of involved fluorophores on obtained mechanical information is normally underestimated, and such subtle changes are still challenging to detect. Herein, we combined AFM with laser light excitation to perform a mechanical quantitative analysis of a model membrane system labeled with a commonly used fluorophore. Mechanical quantification was additionally validated by finite element simulations. Upon staining, we noticed fluorophores forming a diffuse weakly organized overlayer on phospholipid supported membrane, easily detected by AFM mechanics. The laser was found to cause a degradation of mechanical stability of the membrane synergically with presence of fluorophore. In particular, a 30 min laser irradiation, with intensity similar to that in typical confocal scanning microscopy experiment, was found to result in a ∼40% decrease in the breakthrough force of the stained phospholipid bilayer along with a ∼30% reduction in its apparent elastic modulus. The findings highlight the significance of analytical power provided by AFM, which will allow us to “see” the “unseen” in correlative microscopy, as well as the necessity to consider photothermal effects when using fluorescent dyes to investigate, for example, the deformability and permeability of phospholipid membranes.
Collapse
Affiliation(s)
- Massimiliano Galluzzi
- Materials Interfaces Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Bokai Zhang
- Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,DGene (Dongjin Big Health (Shenzhen)) Co., Ltd., Shenzhen, China.,BenHealth Biopharmaceutical (Shenzhen) Co., Ltd., Shenzhen, China
| | - Han Zhang
- Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,State Key Laboratory of Traction Power, Southwest Jiaotong Univerisity, Chengdu, China
| | - Lingzhi Wang
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong
| | - Yuan Lin
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong.,Advanced Biomedical Instrumentation Centre, Shatin, Hong Kong
| | - Xue-Feng Yu
- Materials Interfaces Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Zhiqin Chu
- Department of Electrical and Electronic Engineering, Joint Appointment with School of Biomedical Sciences, The University of Hong Kong, Hong Kong
| | - Jiangyu Li
- Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.,Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, China
| |
Collapse
|
17
|
Khadka NK, Timsina R, Rowe E, O'Dell M, Mainali L. Mechanical properties of the high cholesterol-containing membrane: An AFM study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183625. [PMID: 33891910 DOI: 10.1016/j.bbamem.2021.183625] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 04/02/2021] [Accepted: 04/12/2021] [Indexed: 12/11/2022]
Abstract
Cholesterol (Chol) content in most cellular membranes does not exceed 50 mol%, only in the eye lens's fiber cell plasma membrane, its content surpasses 50 mol%. At this high concentration, Chol induces the formation of pure cholesterol bilayer domains (CBDs), which coexist with the surrounding phospholipid-cholesterol domain (PCD). Here, we applied atomic force microscopy to study the mechanical properties of Chol/phosphatidylcholine membranes where the Chol content was increased from 0 to 75 mol%, relevant to eye lens membranes. The surface roughness of the membrane decreases with an increase of Chol content until it reaches 60 mol%, and roughness increases with a further increment in Chol content. We propose that the increased roughness at higher Chol content results from the formation of CBDs. Force spectroscopy on the membrane with Chol content of 50 mol% or lesser exhibited single breakthrough events, whereas two distinct puncture events were observed for membranes with the Chol content greater than 50 mol%. We propose that the first puncture force corresponds to the membranes containing coexisting PCD and CBDs. In contrast, the second puncture force corresponds to the "CBD water pocket" formed due to coexisting CBDs and PCD. Membrane area compressibility modulus (KA) increases with an increase in Chol content until it reaches 60 mol%, and with further increment in Chol content, CBDs are formed, and KA starts to decrease. Our results report the increase in membrane roughness and decrease KA at very high Chol content (>60 mol%) relevant to the eye lens membrane.
Collapse
Affiliation(s)
- Nawal K Khadka
- Department of Physics, Boise State University, Boise, ID, USA
| | - Raju Timsina
- Department of Physics, Boise State University, Boise, ID, USA
| | - Erica Rowe
- Department of Biology, Boise State University, Boise, ID, USA
| | - Matthew O'Dell
- Biomolecular Sciences Graduate Program, Boise State University, Boise, ID, USA
| | - Laxman Mainali
- Department of Physics, Boise State University, Boise, ID, USA; Biomolecular Sciences Graduate Program, Boise State University, Boise, ID, USA.
| |
Collapse
|
18
|
Kuo YC, Wang IH, Rajesh R. Use of leptin-conjugated phosphatidic acid liposomes with resveratrol and epigallocatechin gallate to protect dopaminergic neurons against apoptosis for Parkinson's disease therapy. Acta Biomater 2021; 119:360-374. [PMID: 33189953 DOI: 10.1016/j.actbio.2020.11.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 11/06/2020] [Accepted: 11/10/2020] [Indexed: 12/12/2022]
Abstract
Complex liposomes were assembled with 1,2-distearoyl-sn-glycero-3-phosphocholine, dihexadecyl phosphate (DHDP), cholesterol and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphate (PA) to act as drug carriers for resveratrol (RES) and epigallocatechin gallate (EGCG). The liposomes were modified with leptin (Lep) on the surface to cross the blood-brain barrier (BBB) and to rescue degenerated dopaminergic neurons. The activity of RES and EGCG against neurotoxicity was investigated using an in vitro neurodegenerative model established by SH-SY5Y cells with an insult of 1-methyl-4-phenylpyridinium (MPP+). The results indicated that increasing the mole percentage of DHDP and PA increased the particle size and absolute zeta potential value, and improved the entrapment efficiency of RES and EGCG; however, this increase reduced the release rate of RES and EGCG and the grafting efficiency of Lep. The ability of Lep/RES-EGCG-PA-liposomes to cross the BBB was found to be higher than that of non-modified liposomes. Further, the addition of PA and Lep into liposomes enhanced cell viability and target efficiency. The immunofluorescence results demonstrated that the conjugation of Lep with liposomes enabled the docking of HBMECs and SH-SY5Y cells via Lep receptor, and enhanced their ability to permeate the BBB and cellular uptake. Immunofluorescence and western blot analysis also revealed that RES and EGCG encapsulated into liposomes could be a neural defensive strategy by reducing the apoptosis promotor protein Bcl-2 associated X protein and α-synuclein, and enhancement in the apoptosis inhibitor protein B cell lymphoma 2, tyrosine hydroxylase, and the dopamine transporter. Hence, Lep-PA-liposomes can be an excellent choice of potential delivery system for PD treatment.
Collapse
Affiliation(s)
- Yung-Chih Kuo
- Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, Taiwan 62102, ROC; Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, Chia-Yi, Taiwan 62102, ROC.
| | - I-Hsin Wang
- Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, Taiwan 62102, ROC
| | - Rajendiran Rajesh
- Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, Taiwan 62102, ROC
| |
Collapse
|
19
|
Redondo-Morata L, Losada-Pérez P, Giannotti MI. Lipid bilayers: Phase behavior and nanomechanics. CURRENT TOPICS IN MEMBRANES 2020; 86:1-55. [PMID: 33837691 DOI: 10.1016/bs.ctm.2020.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Lipid membranes are involved in many physiological processes like recognition, signaling, fusion or remodeling of the cell membrane or some of its internal compartments. Within the cell, they are the ultimate barrier, while maintaining the fluidity or flexibility required for a myriad of processes, including membrane protein assembly. The physical properties of in vitro model membranes as model cell membranes have been extensively studied with a variety of techniques, from classical thermodynamics to advanced modern microscopies. Here we review the nanomechanics of solid-supported lipid membranes with a focus in their phase behavior. Relevant information obtained by quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM) as complementary techniques in the nano/mesoscale interface is presented. Membrane morphological and mechanical characterization will be discussed in the framework of its phase behavior, phase transitions and coexistence, in simple and complex models, and upon the presence of cholesterol.
Collapse
Affiliation(s)
- Lorena Redondo-Morata
- Center for Infection and Immunity of Lille, INSERM U1019, CNRS UMR 8204, Lille, France
| | - Patricia Losada-Pérez
- Experimental Soft Matter and Thermal Physics (EST) Group, Department of Physics, Université Libre de Bruxelles, Brussels, Belgium
| | - Marina Inés Giannotti
- Biomedical Research Networking Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain; Institut de Bioenginyeria de Catalunya (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain; Departament de Ciència de Materials i Química Física, Universitat de Barcelona, Barcelona, Spain.
| |
Collapse
|
20
|
Vázquez RF, Ovalle-García E, Antillón A, Ortega-Blake I, Bakás LS, Muñoz-Garay C, Maté SM. Asymmetric bilayers mimicking membrane rafts prepared by lipid exchange: Nanoscale characterization using AFM-Force spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183467. [PMID: 32871116 DOI: 10.1016/j.bbamem.2020.183467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 08/07/2020] [Accepted: 08/24/2020] [Indexed: 01/03/2023]
Abstract
Sphingolipids-enriched rafts domains are proposed to occur in plasma membranes and to mediate important cellular functions. Notwithstanding, the asymmetric transbilayer distribution of phospholipids that exists in the membrane confers the two leaflets different potentials to form lateral domains as next to no sphingolipids are present in the inner leaflet. How the physical properties of one leaflet can influence the properties of the other and its importance on signal transduction across the membrane are questions still unresolved. In this work, we combined AFM imaging and Force spectroscopy measurements to assess domain formation and to study the nanomechanical properties of asymmetric supported lipid bilayers (SLBs) mimicking membrane rafts. Asymmetric SLBs were formed by incorporating N-palmitoyl-sphingomyelin (16:0SM) into the outer leaflet of preformed 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC)/Cholesterol SLBs through methyl-β-cyclodextrin-mediated lipid exchange. Lipid domains were detected after incorporation of 16:0SM though their phase state varied from gel to liquid ordered (Lo) phase if the procedure was performed at 24 or 37 °C, respectively. When comparing symmetric and asymmetric Lo domains, differences in size and morphology were observed, with asymmetric domains being smaller and more interconnected. Both types of Lo domains showed similar mechanical stability in terms of rupture forces and Young's moduli. Notably, force curves in asymmetric domains presented two rupture events that could be attributed to the sequential rupture of a liquid disordered (Ld) and a Lo phase. Interleaflet coupling in asymmetric Lo domains could also be inferred from those measurements. The experimental approach outlined here would significantly enhance the applicability of membrane models.
Collapse
Affiliation(s)
- Romina F Vázquez
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CCT- La Plata, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, 60 y 120, 1900 La Plata, Argentina; Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, 1900 La Plata, Argentina.
| | - Erasmo Ovalle-García
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210 Cuernavaca, México
| | - Armando Antillón
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210 Cuernavaca, México
| | - Iván Ortega-Blake
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210 Cuernavaca, México
| | - Laura S Bakás
- Centro de Investigación en Proteínas Vegetales (CIProVe), Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, 1900 La Plata, Argentina
| | - Carlos Muñoz-Garay
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210 Cuernavaca, México
| | - Sabina M Maté
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CCT- La Plata, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, 60 y 120, 1900 La Plata, Argentina.
| |
Collapse
|
21
|
Hammond K, Ryadnov MG, Hoogenboom BW. Atomic force microscopy to elucidate how peptides disrupt membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183447. [PMID: 32835656 DOI: 10.1016/j.bbamem.2020.183447] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/30/2020] [Accepted: 08/13/2020] [Indexed: 12/24/2022]
Abstract
Atomic force microscopy is an increasingly attractive tool to study how peptides disrupt membranes. Often performed on reconstituted lipid bilayers, it provides access to time and length scales that allow dynamic investigations with nanometre resolution. Over the last decade, AFM studies have enabled visualisation of membrane disruption mechanisms by antimicrobial or host defence peptides, including peptides that target malignant cells and biofilms. Moreover, the emergence of high-speed modalities of the technique broadens the scope of investigations to antimicrobial kinetics as well as the imaging of peptide action on live cells in real time. This review describes how methodological advances in AFM facilitate new insights into membrane disruption mechanisms.
Collapse
Affiliation(s)
- Katharine Hammond
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, UK; London Centre for Nanotechnology, University College London, London WC1H 0AH, UK; Department of Physics & Astronomy, University College London, London WC1E 6BT, UK.
| | - Maxim G Ryadnov
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, UK; Department of Physics, King's College London, Strand Lane, London WC2R 2LS, UK.
| | - Bart W Hoogenboom
- London Centre for Nanotechnology, University College London, London WC1H 0AH, UK; Department of Physics & Astronomy, University College London, London WC1E 6BT, UK.
| |
Collapse
|
22
|
Deplazes E, Tafalla BD, Cranfield CG, Garcia A. Role of Ion-Phospholipid Interactions in Zwitterionic Phospholipid Bilayer Ion Permeation. J Phys Chem Lett 2020; 11:6353-6358. [PMID: 32687371 DOI: 10.1021/acs.jpclett.0c01479] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Despite the central role of Na+ and K+ in physiological processes, it is still unclear whether they interact or alter the physical properties of simple zwitterionic phospholipid bilayers at physiologically relevant concentrations. Here we report a difference in membrane permeability between Na+ and K+, as measured with electrical impedance spectroscopy and tethered bilayer lipid membranes. We reveal that the differences in membrane permeability originate from distinct ion coordination by carbonyl oxygens at the phospholipid-water interface, altering the propensity for bilayer pore formation. Molecular dynamics simulations showed differences in the coordination of Na+ and K+ at the phospholipid-water interface of zwitterionic phospholipid bilayers. The ability of Na+ to conscript more phospholipids with a greater number of coordinating interactions causes a higher localized energy barrier for pore formation. These results provide evidence that ion-specific interactions at the phospholipid-water interface can modulate the physical properties of zwitterionic phospholipid bilayers.
Collapse
Affiliation(s)
- Evelyne Deplazes
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | | | - Charles G Cranfield
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Alvaro Garcia
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| |
Collapse
|
23
|
Tahirbegi B, Magness AJ, Piersimoni ME, Knöpfel T, Willison KR, Klug DR, Ying L. A Novel Aβ 40 Assembly at Physiological Concentration. Sci Rep 2020; 10:9477. [PMID: 32528074 PMCID: PMC7289798 DOI: 10.1038/s41598-020-66373-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 05/15/2020] [Indexed: 01/27/2023] Open
Abstract
Aggregates of amyloid-β (Aβ) are characteristic of Alzheimer's disease, but there is no consensus as to either the nature of the toxic molecular complex or the mechanism by which toxic aggregates are produced. We report on a novel feature of amyloid-lipid interactions where discontinuities in the lipid continuum can serve as catalytic centers for a previously unseen microscale aggregation phenomenon. We show that specific lipid membrane conditions rapidly produce long contours of lipid-bound peptide, even at sub-physiological concentrations of Aβ. Using single molecule fluorescence, time-lapse TIRF microscopy and AFM imaging we characterize this phenomenon and identify some exceptional properties of the aggregation pathway which make it a likely contributor to early oligomer and fibril formation, and thus a potential critical mechanism in the etiology of AD. We infer that these amyloidogenic events occur only at areas of high membrane curvature, which suggests a range of possible mechanisms by which accumulated physiological changes may lead to their inception. The speed of the formation is in hours to days, even at 1 nM peptide concentrations. Lipid features of this type may act like an assembly line for monomeric and small oligomeric subunits of Aβ to increase their aggregation states. We conclude that under lipid environmental conditions, where catalytic centers of the observed type are common, key pathological features of AD may arise on a very short timescale under physiological concentration.
Collapse
Affiliation(s)
- Bogachan Tahirbegi
- Department of Chemistry, Imperial College London, London, United Kingdom
| | - Alastair J Magness
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | | | - Thomas Knöpfel
- Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Keith R Willison
- Department of Chemistry, Imperial College London, London, United Kingdom
| | - David R Klug
- Department of Chemistry, Imperial College London, London, United Kingdom.
| | - Liming Ying
- National Heart and Lung Institute, Imperial College London, London, United Kingdom.
| |
Collapse
|
24
|
Saavedra V O, Fernandes TFD, Milhiet PE, Costa L. Compression, Rupture, and Puncture of Model Membranes at the Molecular Scale. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:5709-5716. [PMID: 32427478 DOI: 10.1021/acs.langmuir.0c00247] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Elastic properties of biological membranes are involved in a large number of membrane functionalities and activities. Conventionally characterized in terms of Young's modulus, bending stiffness and stretching modulus, membrane mechanics can be assessed at high lateral resolution by means of atomic force microscopy (AFM). Here we show that the mechanical response of biomimetic model systems such as supported lipid bilayers (SLBs) is highly affected by the size of the AFM tip employed as a membrane indenter. Our study is focused on phase-separated fluid-gel lipid membranes at room temperature. In a small tip radius regime (≈ 2 nm) and in the case of fluid phase membranes, we show that the tip can penetrate through the membrane minimizing molecular vertical compression and in absence of molecular membrane rupture. In this case, AFM indentation experiments cannot assess the vertical membrane Young's modulus. In agreement with the data reported in the literature, in the case of larger indenters (>2 nm) SLBs can be compressed leading to an evaluation of Young's modulus and membrane maximal withstanding force before rupture. We show that such force increases with the indenter in agreement with the existing theoretical frame. Finally, we demonstrate that the latter has no influence on the number of molecules involved in the rupture process that is observed to be constant and rather dependent on the indenter chemical composition.
Collapse
Affiliation(s)
- Oscar Saavedra V
- Centre de Biochimie Structurale (CBS), CNRS, INSERM, Univ. Montpellier, 34090 Montpellier, France
| | - Thales F D Fernandes
- Centre de Biochimie Structurale (CBS), CNRS, INSERM, Univ. Montpellier, 34090 Montpellier, France
| | - Pierre-Emmanuel Milhiet
- Centre de Biochimie Structurale (CBS), CNRS, INSERM, Univ. Montpellier, 34090 Montpellier, France
| | - Luca Costa
- Centre de Biochimie Structurale (CBS), CNRS, INSERM, Univ. Montpellier, 34090 Montpellier, France
| |
Collapse
|
25
|
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.
Collapse
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.
| |
Collapse
|
26
|
Utilizing Liposomal Quercetin and Gallic Acid in Localized Treatment of Vaginal Candida Infections. Pharmaceutics 2019; 12:pharmaceutics12010009. [PMID: 31861805 PMCID: PMC7023398 DOI: 10.3390/pharmaceutics12010009] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/13/2019] [Accepted: 12/17/2019] [Indexed: 12/22/2022] Open
Abstract
Vulvovaginal candidiasis (VVC) is a widely spread fungal infection that causes itching, pain and inflammation at the vaginal site. Although common, currently available treatment suffers from limited efficacy and high recurrence. In addition, the growing problem of resistance to azole drugs used in current treatments emphasizes the need for superior treatment options. Antimicrobial polyphenols are an attractive approach offering multitargeting therapy. We aimed to develop novel liposomes for simultaneous delivery of two polyphenols (quercetin, Q, and gallic acid, GA) that, when released within the vaginal cavity, act in synergy to eradicate infection while alleviating the symptoms of VVC. Q was selected for its anti-itching and anti-inflammatory properties, while GA for its reported activity against Candida. Novel liposomes containing only Q (LP-Q), only GA (LP-GA) or both polyphenols (LP-Q+GA) were in the size range around 200 nm. Q was efficiently entrapped in both LP-Q and in LP-Q+GA (85%) while the entrapment of GA was higher in LP-Q+GA (30%) than in LP-GA (25%). Liposomes, especially LP-Q+GA, promoted sustained release of both polyphenols. Q and GA acted in synergy, increasing the antioxidant activities of a single polyphenol. Polyphenol-liposomes were not cytotoxic and displayed stronger anti-inflammatory effects than free polyphenols. Finally, LP-GA and LP-Q+GA considerably reduced C. albicans growth.
Collapse
|
27
|
Dyett BP, Yu H, Strachan J, Drummond CJ, Conn CE. Fusion dynamics of cubosome nanocarriers with model cell membranes. Nat Commun 2019; 10:4492. [PMID: 31582802 PMCID: PMC6776645 DOI: 10.1038/s41467-019-12508-8] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 09/12/2019] [Indexed: 12/24/2022] Open
Abstract
Drug delivery with nanocarriers relies on the interaction of individual nanocarriers with the cell surface. For lipid-based NCs, this interaction uniquely involves a process of membrane fusion between the lipid bilayer that makes up the NC and the cell membrane. Cubosomes have emerged as promising fusogenic NCs, however their individual interactions had not yet been directly observed due to difficulties in achieving adequate resolution or disentangling multiple interactions with common characterization techniques. Moreover, many studies on these interactions have been performed under static conditions which may not mimic the actual transport of NCs. Herein we have observed fusion of lipid cubosome NCs with lipid bilayers under flow. Total internal reflection microscopy has allowed visualisation of the fusion event which was sensitive to the lipid compositions and rationalized by lipid diffusion. The fusion event in supported lipid bilayers has been compared with those in cells, revealing a distinct similarity in kinetics.
Collapse
Affiliation(s)
- Brendan P Dyett
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia
| | - Haitao Yu
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia
| | - Jamie Strachan
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia
| | - Calum J Drummond
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia.
| | - Charlotte E Conn
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia.
| |
Collapse
|
28
|
Abraham S, Heckenthaler T, Morgenstern Y, Kaufman Y. Effect of Temperature on the Structure, Electrical Resistivity, and Charge Capacitance of Supported Lipid Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:8709-8715. [PMID: 31244251 DOI: 10.1021/acs.langmuir.9b00726] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Supported lipid bilayers with incorporated membrane proteins have promising potential for diverse applications, such as filtration processes, drug delivery, and biosensors. For these applications, the continuity (lack of defects), electrical resistivity, and charge capacitance of the lipid bilayers are crucial. Here, we highlight the effects of temperature changes and the rate of temperature changes on the vertical and lateral expansion and contraction of lipid bilayers, which in turn affect the lipid bilayer resistivity and capacitance. We focused on lipid bilayers that consist of 50 mol % dimyristoyl- sn-glycero-3-phosphocholine (zwitterionic lipid) and 50 mol % dimyristoyl-3-trimethylammonium-propane (positively charged lipid) lipids. This lipid mixture is known to self-assemble into a continuous lipid bilayer on silicon wafers. It is shown experimentally and explained theoretically that slow cooling (e.g., -0.4 °C min-1) increases the resistivity significantly and reduces the capacitance of lipid bilayers, and these trends are reversed by heating. However, fast cooling (∼ -10 °C min-1 or faster) damages the membrane and reduces the resistivity and capacitance of lipid bilayers to practically zero. Importantly, the addition of 50 mol % cholesterol to lipid bilayers prevents the resistivity and capacitance reduction after fast cooling. It is argued that the ratio of lipid diffusion coefficient to thermal expansion/contraction rate (proportional to the heating/cooling rate) is the crucial parameter that determines the effects of temperature changes on lipids bilayers. A high ratio (fast lipid diffusion) increases the lipid bilayer resistivity and decreases the capacitance upon cooling and vice versa. Similar trends are expected for lipid membranes that consist of other lipids or lipidlike mixtures.
Collapse
Affiliation(s)
- Shiju Abraham
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer 8499000 , Israel
| | - Tabea Heckenthaler
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer 8499000 , Israel
| | - Yakov Morgenstern
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer 8499000 , Israel
| | - Yair Kaufman
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer 8499000 , Israel
- Center for Bioengineering , University of California Santa Barbara , Santa Barbara , California 93106 , United States
| |
Collapse
|
29
|
Deplazes E, White J, Murphy C, Cranfield CG, Garcia A. Competing for the same space: protons and alkali ions at the interface of phospholipid bilayers. Biophys Rev 2019; 11:483-490. [PMID: 31115866 DOI: 10.1007/s12551-019-00541-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 04/29/2019] [Indexed: 10/26/2022] Open
Abstract
Maintaining gradients of solvated protons and alkali metal ions such as Na+ and K+ across membranes is critical for cellular function. Over the last few decades, both the interactions of protons and alkali metal ions with phospholipid membranes have been studied extensively and the reported interactions of these ions with phospholipid headgroups are very similar, yet few studies have investigated the potential interdependence between proton and alkali metal ion binding at the water-lipid interface. In this short review, we discuss the similarities between the proton-membrane and alkali ion-membrane interactions. Such interactions include cation attraction to the phosphate and carbonyl oxygens of the phospholipid headgroups that form strong lipid-ion and lipid-ion-water complexes. We also propose potential mechanisms that may modulate the affinities of these cationic species to the water-phospholipid interfacial oxygen moieties. This review aims to highlight the potential interdependence between protons and alkali metal ions at the membrane surface and encourage a more nuanced understanding of the complex nature of these biologically relevant processes.
Collapse
Affiliation(s)
- Evelyne Deplazes
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia. .,School of Pharmacy and Biomedical Sciences, Curtin University, Perth, WA, 6845, Australia.
| | - Jacqueline White
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Christopher Murphy
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Charles G Cranfield
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Alvaro Garcia
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia.
| |
Collapse
|
30
|
Trewby W, Faraudo J, Voïtchovsky K. Long-lived ionic nano-domains can modulate the stiffness of soft interfaces. NANOSCALE 2019; 11:4376-4384. [PMID: 30801089 DOI: 10.1039/c8nr06339g] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Metal ions underpin countless processes at bio-interfaces, including maintaining electroneutrality, modifying mechanical properties and driving bioenergetic activity. These processes are typically described by ions behaving as independently diffusing point charges. Here we show that Na+ and K+ ions instead spontaneously form correlated nanoscale networks that evolve over seconds at the interface with an anionic bilayer in solution. Combining single-ion level atomic force microscopy and molecular dynamic simulations we investigate the configuration and dynamics of Na+, K+, and Rb+ at the lipid surface. We identify two distinct ionic states: the well-known direct electrostatic interaction with lipid headgroups and a water-mediated interaction that can drive the formation of remarkably long-lived ionic networks which evolve over many seconds. We show that this second state induces ionic network formation via correlative ion-ion interactions that generate an effective energy well of -0.4kBT/ion. These networks locally reduce the stiffness of the membrane, providing a spontaneous mechanism for tuning its mechanical properties with nanoscale precision. The ubiquity of water-mediated interactions suggest that our results have far-reaching implications for controlling the properties of soft interfaces.
Collapse
Affiliation(s)
- William Trewby
- University of Durham, Physics Department, Durham DH1 3LE, UK.
| | | | | |
Collapse
|
31
|
Kempter S, Khmelinskaia A, Strauss MT, Schwille P, Jungmann R, Liedl T, Bae W. Single Particle Tracking and Super-Resolution Imaging of Membrane-Assisted Stop-and-Go Diffusion and Lattice Assembly of DNA Origami. ACS NANO 2019; 13:996-1002. [PMID: 30588792 DOI: 10.1021/acsnano.8b04631] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
DNA nanostructures offer the possibility to mimic functional biological membrane components due to their nanometer-precise shape configurability and versatile biochemical functionality. Here we show that the diffusional behavior of DNA nanostructures and their assembly into higher order membrane-bound lattices can be controlled in a stop-and-go manner and that the process can be monitored with super-resolution imaging. The DNA structures are transiently immobilized on glass-supported lipid bilayers by changing the mono- and divalent cation concentrations of the surrounding buffer. Using DNA points accumulation for imaging in nanoscale topography (DNA-PAINT) super-resolution microscopy, we confirm the fixation of DNA origami structures with different shapes. On mica-supported lipid bilayers, in contrast, we observe residual movement. By increasing the concentration of NaCl and depleting MgCl2, a large fraction of DNA structures restarts to diffuse freely on both substrates. After addition of a set of oligonucleotides that enables three Y-shaped monomers to assemble into a three-legged shape (triskelion), the triskelions can be stopped and super-resolved. Exchanging buffer and adding another set of oligonucleotides triggers the triskelions to diffuse and assemble into hexagonal 2D lattices. This stop-and-go imaging technique provides a way to control and observe the diffusional behavior of DNA nanostructures on lipid membranes that could also lead to control of membrane-associated cargos.
Collapse
Affiliation(s)
- Susanne Kempter
- Faculty of Physics and Center for NanoScience , Ludwig-Maximilians-Universität , München 80539 , Germany
| | | | - Maximilian T Strauss
- Faculty of Physics and Center for NanoScience , Ludwig-Maximilians-Universität , München 80539 , Germany
- Max Planck Institute of Biochemistry , Martinsried 82152 , Germany
| | - Petra Schwille
- Max Planck Institute of Biochemistry , Martinsried 82152 , Germany
| | - Ralf Jungmann
- Faculty of Physics and Center for NanoScience , Ludwig-Maximilians-Universität , München 80539 , Germany
- Max Planck Institute of Biochemistry , Martinsried 82152 , Germany
| | - Tim Liedl
- Faculty of Physics and Center for NanoScience , Ludwig-Maximilians-Universität , München 80539 , Germany
| | - Wooli Bae
- Faculty of Physics and Center for NanoScience , Ludwig-Maximilians-Universität , München 80539 , Germany
| |
Collapse
|
32
|
Dobrzyńska I. Association equilibria of divalent ions on the surface of liposomes formed from phosphatidylcholine. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2019; 42:3. [PMID: 30643999 DOI: 10.1140/epje/i2019-11762-6] [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] [Received: 06/06/2018] [Accepted: 12/03/2018] [Indexed: 06/09/2023]
Abstract
Divalent ions, in particular calcium ions, constitute important macroelements in living organisms. They are also found in cell membranes, i.e., ensuring their stabilization or participating in synaptic transmission of nerve impulses. The aim of this work is to describe the interactions of divalent ions, such as Ca2+, Ba2+, and Sr2+, in electrolytes with the functional groups on the surface of liposomes formed from phosphatidylcholine (PC). Microelectrophoresis is used to determine the surface charge density as a function of pH. The interactions between ions found in solution and the functional groups of PC are described with the use of a seven-equilibrium mathematical model. Using this model along with experimental data on the charge density of the membrane surface, the association constants characterizing this equilibrium are determined. These parameters are used to calculate the theoretical model curves. The validity of the proposed model is confirmed by comparing the theoretically calculated changes in charge density on the liposome surface with the experimental results.
Collapse
Affiliation(s)
- Izabela Dobrzyńska
- Institute of Chemistry, University of Białystok, Ciołkowskiego 1K, 15-245, Białystok, Poland.
| |
Collapse
|
33
|
Morris RJ. Thy-1, a Pathfinder Protein for the Post-genomic Era. Front Cell Dev Biol 2018; 6:173. [PMID: 30619853 PMCID: PMC6305390 DOI: 10.3389/fcell.2018.00173] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 12/06/2018] [Indexed: 12/21/2022] Open
Abstract
Thy-1 is possibly the smallest of cell surface proteins – 110 amino acids folded into an Immunoglobulin variable domain, tethered to the outer leaflet of the cell surface membrane via just the two saturated fatty acids of its glycosylphosphatidylinositol (GPI) anchor. Yet Thy-1 is emerging as a key regulator of differentiation in cells of endodermal, mesodermal, and ectodermal origin, acting as both a ligand (for certain integrins and other receptors), and as a receptor, able to modulate signaling and hence differentiation in the Thy-1-expressing cell. This is an extraordinary diversity of molecular pathways to be controlled by a molecule that does not even cross the cell membrane. Here I review aspects of the cell biology of Thy-1, and studies of its role as deduced from gene knock-out studies, that suggest how this protein can participate in so many different signaling-related functions. While mechanisms differ in molecular detail, it appears overall that Thy-1 dampens down signaling to control function.
Collapse
Affiliation(s)
- Roger J Morris
- Department of Chemistry, King's College London, London, United Kingdom
| |
Collapse
|
34
|
Gumí-Audenis B, Illa-Tuset S, Grimaldi N, Pasquina-Lemonche L, Ferrer-Tasies L, Sanz F, Veciana J, Ratera I, Faraudo J, Ventosa N, Giannotti MI. Insights into the structure and nanomechanics of a quatsome membrane by force spectroscopy measurements and molecular simulations. NANOSCALE 2018; 10:23001-23011. [PMID: 30500043 DOI: 10.1039/c8nr07110a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Quatsomes (QS) are unilamellar nanovesicles constituted by quaternary ammonium surfactants and sterols in defined molar ratios. Unlike conventional liposomes, QS are stable upon long storage such as for several years, they show outstanding vesicle-to-vesicle homogeneity regarding size and lamellarity, and they have the structural and physicochemical requirements to be a potential platform for site-specific delivery of hydrophilic and lipophilic molecules. Knowing in detail the structure and mechanical properties of the QS membrane is of great importance for the design of deformable and flexible nanovesicle alternatives, highly pursued in nanomedicine applications such as the transdermal administration route. In this work, we report the first study on the detailed structure of the cholesterol : CTAB QS membrane at the nanoscale, using atomic force microscopy (AFM) and spectroscopy (AFM-FS) in a controlled liquid environment (ionic medium and temperature) to assess the topography of supported QS membranes (SQMs) and to evaluate the local membrane mechanics. We further perform molecular dynamics (MD) simulations to provide an atomistic interpretation of the obtained results. Our results are direct evidence of the bilayer nature of the QS membrane, with characteristics of a fluid-like membrane, compact and homogeneous in composition, and with structural and mechanical properties that depend on the surrounding environment. We show how ions alter the lateral packing, modifying the membrane mechanics. We observe that according to the ionic environment and temperature, different domains may coexist in the QS membranes, ascribed to variations in molecular tilt angles. Our results indicate that QS membrane properties may be easily tuned by altering the lateral interactions with either different environmental ions or counterions.
Collapse
Affiliation(s)
- Berta Gumí-Audenis
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Phase-segregated Membrane Model assessed by a combined SPR-AFM Approach. Colloids Surf B Biointerfaces 2018; 172:423-429. [DOI: 10.1016/j.colsurfb.2018.08.066] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 08/09/2018] [Accepted: 08/29/2018] [Indexed: 12/22/2022]
|
36
|
Trzaskowska PA, Poniatowska A, Trzaskowski M, Latocha J, Ozga P, Major R, Ciach T. Lecithin suspensions for electrophoretic deposition on stainless steel coatings. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2018; 93:134-144. [DOI: 10.1016/j.msec.2018.07.052] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 07/06/2018] [Accepted: 07/20/2018] [Indexed: 10/28/2022]
|
37
|
Galvanetto N. Single-cell unroofing: probing topology and nanomechanics of native membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:2532-2538. [DOI: 10.1016/j.bbamem.2018.09.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/19/2018] [Accepted: 09/26/2018] [Indexed: 10/28/2022]
|
38
|
Effects of mono- and di-valent metal cations on the morphology of lipid vesicles. Chem Phys Lipids 2018; 217:19-28. [PMID: 30253127 DOI: 10.1016/j.chemphyslip.2018.09.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/09/2018] [Accepted: 09/18/2018] [Indexed: 12/22/2022]
Abstract
Lipid vesicles are an attractive model membrane experimental platform that is widely used in a biological context. The stability of vesicles can affect their performance and depends on various experimental conditions. How bio-related ions affect vesicle morphology is poorly understood in some cases. Herein, we investigated changes in vesicle morphology influenced by cation in the static and flowing environments. The effects of different mono- and di-valent metal cations on the morphology of lipid vesicles were systematically studied using the various techniques. The results showed that divalent cations caused significant aggregation or fusion of lipid vesicles, but monovalent cations had little effect on the vesicle morphology. Cation binding increased the net surface potential of vesicles, leading to changes in the zeta potential. The same qualitative kinetics were observed for cations that had the same valence at the same ionic strength. However, different types of cations gave different quantitative effects. The order of the ability to destroy the vesicle morphology was Cu2+ > Mg2+ > Ca2+ > Na+ > K+. These results are of practical value in the use of lipid vesicles as a bionic model, and help to shed light on the role of ions at membrane surfaces and interfaces.
Collapse
|
39
|
Liu X. Interactions of Silver Nanoparticles Formed in Situ on AFM Tips with Supported Lipid Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:10774-10781. [PMID: 30109936 DOI: 10.1021/acs.langmuir.8b01545] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A facile approach for functionalizing atomic force microscopy (AFM) tips with nanoparticles (NPs) will provide exciting opportunities in the field of tip-enhanced vibrational spectroscopy and in probing the interactions between NPs and biological systems. In this study, through successive exposure to polydopamine and AgNO3 solutions, the apex of AFM tips was functionalized with silver nanoparticles (AgNPs). The AgNP-modified AFM tips were used to measure the interaction forces between AgNPs and supported lipid bilayers (SLBs) formed on mica, as well as to probe the penetration of SLBs by AgNPs, with an emphasis on the effect of human serum albumin (HSA) proteins. AgNPs experienced predominantly repulsive forces when approaching SLBs. The presence of HSA resulted in an enhancement in the repulsive interactions between AgNPs and SLBs, likely through steric repulsion. Finally, the forces required for AgNPs to penetrate SLBs were higher in the presence of HSA probably due to the increase in the effective size of the nanoscale protuberances on the AFM tip stemming from the formation of protein coronas around the AgNPs.
Collapse
Affiliation(s)
- Xitong Liu
- Department of Environmental Health and Engineering , Johns Hopkins University , Baltimore , Maryland 21218-2686 , United States
| |
Collapse
|
40
|
Kontogiannopoulos KN, Dasargyri A, Ottaviani MF, Cangiotti M, Fessas D, Papageorgiou VP, Assimopoulou AN. Advanced Drug Delivery Nanosystems for Shikonin: A Calorimetric and Electron Paramagnetic Resonance Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:9424-9434. [PMID: 30032619 DOI: 10.1021/acs.langmuir.8b00751] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Drug delivery is considered a mature scientific and technological platform for producing innovative medicines with nanosystems composed of intelligent bio-materials that carry active pharmaceutical ingredients forming advanced drug delivery nanosystems (aDDnSs). Shikonin and its enantiomer alkannin are natural products that have been extensively studied in vitro and in vivo for, among others, their antitumor activity, and various efforts have been made to prepare shikonin-loaded drug delivery systems. This study is focused on chimeric aDDnSs and specifically on liposomal formulations combining three lipids (egg-phosphatidylcholine; dipalmitoyl phosphatidylcholine; and distearoyl phosphatidylcholine) and a hyperbranched polymer (PFH-64-OH). Furthermore, PEGylated liposomal formulations of all samples were also prepared. Calorimetric techniques and electron paramagnetic resonance were used to explore and evaluate the interactions and stability of the liposomal formulations, showing that the presence of hyperbranched polymers promote the overall stability of the chimeric aDDnSs based on the drug release profile enhancement. Furthermore, results showed that polyethylene glycol enhances drug stabilization inside the liposomes, forming a stable and promising carrier for shikonin with improved characteristics.
Collapse
Affiliation(s)
- Konstantinos N Kontogiannopoulos
- Organic Chemistry Laboratory, School of Chemical Engineering , Aristotle University of Thessaloniki , 54124 Thessaloniki , Greece
| | - Athanasia Dasargyri
- Organic Chemistry Laboratory, School of Chemical Engineering , Aristotle University of Thessaloniki , 54124 Thessaloniki , Greece
| | - M Francesca Ottaviani
- Department of Pure and Applied Sciences, Scientific Campus E. Mattei , University of Urbino , 61029 Urbino , Italy
| | - Michela Cangiotti
- Department of Pure and Applied Sciences, Scientific Campus E. Mattei , University of Urbino , 61029 Urbino , Italy
| | - Dimitrios Fessas
- Department of Food, Environmental and Nutritional Sciences (DeFENS) , Università degli Studi di Milano , Via Celoria 2 , 20133 Milano , Italy
| | - Vassilios P Papageorgiou
- Organic Chemistry Laboratory, School of Chemical Engineering , Aristotle University of Thessaloniki , 54124 Thessaloniki , Greece
| | - Andreana N Assimopoulou
- Organic Chemistry Laboratory, School of Chemical Engineering , Aristotle University of Thessaloniki , 54124 Thessaloniki , Greece
| |
Collapse
|
41
|
Gumí-Audenis B, Costa L, Ferrer-Tasies L, Ratera I, Ventosa N, Sanz F, Giannotti MI. Pulling lipid tubes from supported bilayers unveils the underlying substrate contribution to the membrane mechanics. NANOSCALE 2018; 10:14763-14770. [PMID: 30043793 DOI: 10.1039/c8nr03249a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Cell processes like endocytosis, membrane resealing, signaling and transcription involve conformational changes which depend on the chemical composition and the physicochemical properties of the lipid membrane. The better understanding of the mechanical role of lipids in cell membrane force-triggered and sensing mechanisms has recently become the focus of attention. Different membrane models and experimental methodologies are commonly explored. While general approaches involve controlled vesicle deformation using micropipettes or optical tweezers, due to the local and dynamic nature of the membrane, high spatial resolution atomic force microscopy (AFM) has been widely used to study the mechanical compression and indentation of supported lipid bilayers (SLBs). However, the substrate contribution remains unkown. Here, we demonstrate how pulling lipid tubes with an AFM out of model SLBs can be used to assess the nanomechanics of SLBs through the evaluation of the tube growing force (Ftube), allowing for very local evaluation with high spatial and force resolution of the lipid membrane tension. We first validate this approach to determine the contribution of different phospholipids, by varying the membrane composition, in both one-component and phase-segregated membranes. Finally, we successfully assess the contribution of the underlying substrate to the membrane mechanics, demonstrating that SLB models may represent an intermediate scenario between a free membrane (blebs) and a cytoskeleton supported membrane.
Collapse
Affiliation(s)
- Berta Gumí-Audenis
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10-12, 08028 Barcelona, Spain.
| | | | | | | | | | | | | |
Collapse
|
42
|
Rezaei Sani SM, Akhavan M, Jalili S. Salt-induced effects on natural and inverse DPPC lipid membranes: Molecular dynamics simulation. Biophys Chem 2018; 239:7-15. [DOI: 10.1016/j.bpc.2018.04.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/22/2018] [Accepted: 04/22/2018] [Indexed: 11/29/2022]
|
43
|
Ishiyama T, Shirai S, Okumura T, Morita A. Molecular dynamics study of structure and vibrational spectra at zwitterionoic lipid/aqueous KCl, NaCl, and CaCl 2 solution interfaces. J Chem Phys 2018; 148:222801. [PMID: 29907059 DOI: 10.1063/1.5006543] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Molecular dynamics (MD) simulations of KCl, NaCl, and CaCl2 solution/dipalmytoylphosphatidylcholine lipid interfaces were performed to analyze heterodyne-detected vibrational sum frequency generation (HD-VSFG) spectra in relation to the interfacial water structure. The present MD simulation well reproduces the experimental spectra and elucidates a specific cation effect on the interfacial structure. The K+, Na+, and Ca2+ cation species penetrate in the lipid layer more than the anions in this order, due to the electrostatic interaction with negative polar groups of lipid, and the electric double layer between the cations and anions cancels the intrinsic orientation of water at the water/lipid interface. These mechanisms explain the HD-VSFG spectrum of the water/lipid interface and its spectral perturbation by adding the ions. The lipid monolayer reverses the order of surface preference of the cations at the solution/lipid interface from that at the solution/air interface.
Collapse
Affiliation(s)
- Tatsuya Ishiyama
- Department of Applied Chemistry, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan
| | - Shinnosuke Shirai
- Department of Applied Chemistry, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan
| | - Tomoaki Okumura
- Department of Applied Chemistry, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan
| | - Akihiro Morita
- Department of Chemistry, Graduate School of Science Tohoku University, Sendai 980-8578, Japan and Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto 615-8520, Japan
| |
Collapse
|
44
|
Smith AK, Klimov DK. Binding of Cytotoxic Aβ25–35 Peptide to the Dimyristoylphosphatidylcholine Lipid Bilayer. J Chem Inf Model 2018; 58:1053-1065. [DOI: 10.1021/acs.jcim.8b00045] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Amy K. Smith
- School of Systems Biology, George Mason University, Manassas, Virginia 20110, United States
| | - Dmitri K. Klimov
- School of Systems Biology, George Mason University, Manassas, Virginia 20110, United States
| |
Collapse
|
45
|
Watanabe A, Niu J, Lunn DJ, Lawrence J, Knight AS, Zhang M, Hawker CJ. PET‐RAFT as a facile strategy for preparing functional lipid–polymer conjugates. ACTA ACUST UNITED AC 2018. [DOI: 10.1002/pola.29007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Akira Watanabe
- Materials Research LaboratoryUniversity of CaliforniaSanta Barbara California93106
| | - Jia Niu
- Department of ChemistryBoston CollegeChestnut Hill Massachusetts02467
- California NanoSystems Institute, University of CaliforniaSanta Barbara California93106
| | - David J. Lunn
- Materials Research LaboratoryUniversity of CaliforniaSanta Barbara California93106
- Department of ChemistryUniversity of OxfordOxfordOX1 3TA United Kingdom
| | - Jimmy Lawrence
- Materials Research LaboratoryUniversity of CaliforniaSanta Barbara California93106
| | - Abigail S. Knight
- Materials Research LaboratoryUniversity of CaliforniaSanta Barbara California93106
| | - Mengwen Zhang
- Department of Chemical EngineeringUniversity of CaliforniaSanta Barbara California93106
| | - Craig J. Hawker
- Materials Research LaboratoryUniversity of CaliforniaSanta Barbara California93106
- California NanoSystems Institute, University of CaliforniaSanta Barbara California93106
- Materials DepartmentUniversity of CaliforniaSanta Barbara California93106
- Department of Chemistry & BiochemistryUniversity of CaliforniaSanta Barbara California93106
| |
Collapse
|
46
|
Kim S, Lee J, Chang R. Plasma-induced Water Pore Formation in Model Cell Membranes: Molecular Dynamics Simulation. B KOREAN CHEM SOC 2018. [DOI: 10.1002/bkcs.11421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Seonghan Kim
- Department of Chemistry; Kwangwoon University; Seoul 01897 Republic of Korea
| | - Junyeol Lee
- Department of Chemistry; Kwangwoon University; Seoul 01897 Republic of Korea
| | - Rakwoo Chang
- Department of Chemistry; Kwangwoon University; Seoul 01897 Republic of Korea
| |
Collapse
|
47
|
Bhojoo U, Chen M, Zou S. Temperature induced lipid membrane restructuring and changes in nanomechanics. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:700-709. [DOI: 10.1016/j.bbamem.2017.12.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 11/17/2017] [Accepted: 12/08/2017] [Indexed: 11/26/2022]
|
48
|
Bakarić D, Petrov D, Mouvenchery YK, Heiβler S, Oostenbrink C, Schaumann GE. Ion-induced modification of the sucrose network and its impact on melting of freeze-dried liposomes. DSC and molecular dynamics study. Chem Phys Lipids 2017; 210:38-46. [PMID: 29179944 DOI: 10.1016/j.chemphyslip.2017.11.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 11/14/2017] [Accepted: 11/23/2017] [Indexed: 02/07/2023]
Abstract
Disaccharides play an important role in survival of anhydrobiotic organisms during extreme environmental conditions. A key protection feature is their capability to form the hydrogen bond (HB) network in a similar fashion as the one made by water. Since various ions also affect the HB network in completely hydrated systems, it is of a great interest to understand how they impact preservation when incorporated in a disaccharide network. To address this, we employ a combination of experimental and modeling techniques to study behavior of multilamellar 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) liposomes freeze-dried with sucrose in presence of NaCl or NaH2PO4·H2O at various concentrations (0.01-1M). Differential scanning calorimetry (DSC) was employed in order to determine the cooperative unit size (CUS), the number of lipid molecules that constitute a domain of cooperative motion in the liposome, and the melting temperature (Tm). In the absence of salt CUS was estimated to be 122±12, whereas in the presence of NaCl CUS increases more (347±34 for c=1M) than for NaH2PO4·H2O (193±26 for 1M). When it comes to Tm, the situation is reversed; NaCl induces increase by about 1K, while NaH2PO4·H2O by about 10K. These findings clearly demonstrate how different interaction forces-hydrogen bonding, charge pairing, and van der Waals interactions between acyl chains-affect CUS and Tm. Their interplay and contribution of particular interaction was further analyzed with molecular dynamics (MD) simulations. This analysis demonstrated that the HB network of DMPC and sucrose is partially disrupted in the presence of NaCl ions, and even to a greater extent in the case of NaH2PO4·H2O ions. Notably, H2PO4- ions outcompete and replace the sucrose molecules at the DMPC surface, which in turn alters the nature of the DMPC-surrounding interactions, from a weaker HB-dominated to a stronger CP-dominated interaction network.
Collapse
Affiliation(s)
- Danijela Bakarić
- University of Koblenz-Landau, Institute for Environmental Sciences, Group of Environmental and Soil Chemistry, Fortstraße 7, D-76829 Landau, Germany.
| | - Dražen Petrov
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences Vienna, Muthgasse 18, A-1190 Vienna, Austria
| | - Yamuna Kunhi Mouvenchery
- University of Koblenz-Landau, Institute for Environmental Sciences, Group of Environmental and Soil Chemistry, Fortstraße 7, D-76829 Landau, Germany
| | - Stefan Heiβler
- Institute for Functional Interfaces, Karlsruhe Institute for Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Chris Oostenbrink
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences Vienna, Muthgasse 18, A-1190 Vienna, Austria
| | - Gabriele E Schaumann
- University of Koblenz-Landau, Institute for Environmental Sciences, Group of Environmental and Soil Chemistry, Fortstraße 7, D-76829 Landau, Germany.
| |
Collapse
|
49
|
Micklavzina BL, Longo ML. Characterization of Repulsive Forces and Surface Deformation in Thin Micellar Films via AFM. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:10483-10491. [PMID: 28903007 DOI: 10.1021/acs.langmuir.7b02508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Here we examine how the force on an atomic force microscope (AFM) tip varies as it approaches micellar surfactant films, and use this information to discern the film's surface structure and Young's modulus. Rows of wormlike hemimicelles were created at a graphite interface using 10 mM sodium dodecyl sulfate (SDS). We found that the repulsive force on a silicon nitride tip as it approached the surface was exponential, with a decay length of 2.0 ± 0.1 nm. The addition of Na2SO4 was found to cause a change in this behavior, with a clear split into two exponential regions at concentrations above 1 mM. We also observed that the range of these forces increased with added salt from ∼15 nm in pure SDS to ∼20 nm at a Na2SO4 concentration of 1.34 mM. These forces were inconsistent with electrostatic repulsion, and were determined to be steric in nature. We show that the behavior at higher salt concentrations is consistent with the theory of polyelectrolyte brushes in the osmotic regime. From this, we hypothesize the presence of micellar brushes at the surface that behave similarly to adsorbed polymer chains. In addition, the Young's modulus of the film was taken from data near the interface using Sneddon's model, and found to be 80 ± 40 MPa. Similar experiments were performed with 10 mM dodecylamine hydrochloride (DAH) solutions in the presence of added magnesium chloride. The decay length for the pure DAH solution was found to be 2.6 ± 0.3 nm, and the addition of 1.34 mM of MgCl2 caused this to increase to 3.7 ± 0.3 nm. No decay length splitting was observed for DAH. We conclude that the behavior at the surface resembles that of an uncharged polymer brush, as the ionic and surface charge densities are much lower for DAH than for SDS.
Collapse
Affiliation(s)
- Benjamin L Micklavzina
- Department of Materials Science and Engineering, University of California Davis , Davis, California 95616, United States
| | - Marjorie L Longo
- Department of Chemical Engineering, University of California Davis , Davis, California 95616, United States
| |
Collapse
|
50
|
Piantanida L, Bolt HL, Rozatian N, Cobb SL, Voïtchovsky K. Ions Modulate Stress-Induced Nanotexture in Supported Fluid Lipid Bilayers. Biophys J 2017; 113:426-439. [PMID: 28746853 PMCID: PMC5529180 DOI: 10.1016/j.bpj.2017.05.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 05/22/2017] [Accepted: 05/30/2017] [Indexed: 12/13/2022] Open
Abstract
Most plasma membranes comprise a large number of different molecules including lipids and proteins. In the standard fluid mosaic model, the membrane function is effected by proteins whereas lipids are largely passive and serve solely in the membrane cohesion. Here we show, using supported 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid bilayers in different saline solutions, that ions can locally induce ordering of the lipid molecules within the otherwise fluid bilayer when the latter is supported. This nanoordering exhibits a characteristic length scale of ∼20 nm, and manifests itself clearly when mechanical stress is applied to the membrane. Atomic force microscopy (AFM) measurements in aqueous solutions containing NaCl, KCl, CaCl2, and Tris buffer show that the magnitude of the effect is strongly ion-specific, with Ca2+ and Tris, respectively, promoting and reducing stress-induced nanotexturing of the membrane. The AFM results are complemented by fluorescence recovery after photobleaching experiments, which reveal an inverse correlation between the tendency for molecular nanoordering and the diffusion coefficient within the bilayer. Control AFM experiments on other lipids and at different temperatures support the hypothesis that the nanotexturing is induced by reversible, localized gel-like solidification of the membrane. These results suggest that supported fluid phospholipid bilayers are not homogenous at the nanoscale, but specific ions are able to locally alter molecular organization and mobility, and spatially modulate the membrane’s properties on a length scale of ∼20 nm. To illustrate this point, AFM was used to follow the adsorption of the membrane-penetrating antimicrobial peptide Temporin L in different solutions. The results confirm that the peptides do not absorb randomly, but follow the ion-induced spatial modulation of the membrane. Our results suggest that ionic effects have a significant impact for passively modulating the local properties of biological membranes, when in contact with a support such as the cytoskeleton.
Collapse
Affiliation(s)
- Luca Piantanida
- Department of Physics, Durham University, Durham, United Kingdom
| | - Hannah L Bolt
- Department of Chemistry, Durham University, Durham, United Kingdom
| | - Neshat Rozatian
- Department of Chemistry, Durham University, Durham, United Kingdom
| | - Steven L Cobb
- Department of Chemistry, Durham University, Durham, United Kingdom
| | | |
Collapse
|