1
|
Aleksanyan M, Grafmüller A, Crea F, Georgiev VN, Yandrapalli N, Block S, Heberle J, Dimova R. Photomanipulation of Minimal Synthetic Cells: Area Increase, Softening, and Interleaflet Coupling of Membrane Models Doped with Azobenzene-Lipid Photoswitches. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2304336. [PMID: 37653602 PMCID: PMC10625111 DOI: 10.1002/advs.202304336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/24/2023] [Indexed: 09/02/2023]
Abstract
Light can effectively interrogate biological systems in a reversible and physiologically compatible manner with high spatiotemporal precision. Understanding the biophysics of photo-induced processes in bio-systems is crucial for achieving relevant clinical applications. Employing membranes doped with the photolipid azobenzene-phosphatidylcholine (azo-PC), a holistic picture of light-triggered changes in membrane kinetics, morphology, and material properties obtained from correlative studies on cell-sized vesicles, Langmuir monolayers, supported lipid bilayers, and molecular dynamics simulations is provided. Light-induced membrane area increases as high as ≈25% and a ten-fold decrease in the membrane bending rigidity is observed upon trans-to-cis azo-PC isomerization associated with membrane leaflet coupling and molecular curvature changes. Vesicle electrodeformation measurements and atomic force microscopy reveal that trans azo-PC bilayers are thicker than palmitoyl-oleoyl phosphatidylcholine (POPC) bilayers but have higher specific membrane capacitance and dielectric constant suggesting an increased ability to store electric charges across the membrane. Lastly, incubating POPC vesicles with azo-PC solutions results in the insertion of azo-PC in the membrane enabling them to become photoresponsive. All these results demonstrate that light can be used to finely manipulate the shape, mechanical and electric properties of photolipid-doped minimal cell models, and liposomal drug carriers, thus, presenting a promising therapeutic alternative for the repair of cellular disorders.
Collapse
Affiliation(s)
- Mina Aleksanyan
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
- Institute for Chemistry and BiochemistryFreie Universität Berlin14195BerlinGermany
| | - Andrea Grafmüller
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
| | - Fucsia Crea
- Department of PhysicsFreie Universität Berlin14195BerlinGermany
| | - Vasil N. Georgiev
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
| | - Naresh Yandrapalli
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
| | - Stephan Block
- Institute for Chemistry and BiochemistryFreie Universität Berlin14195BerlinGermany
| | - Joachim Heberle
- Department of PhysicsFreie Universität Berlin14195BerlinGermany
| | - Rumiana Dimova
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
| |
Collapse
|
2
|
Avalos-Padilla Y, Georgiev VN, Ewins E, Robinson T, Orozco E, Lipowsky R, Dimova R. Stepwise remodeling and subcompartment formation in individual vesicles by three ESCRT-III proteins. iScience 2022; 26:105765. [PMID: 36590172 PMCID: PMC9800321 DOI: 10.1016/j.isci.2022.105765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/21/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
The endosomal sorting complex required for transport (ESCRT) is a multi-protein machinery involved in several membrane remodeling processes. Different approaches have been used to resolve how ESCRT proteins scission membranes. However, the underlying mechanisms generating membrane deformations are still a matter of debate. Here, giant unilamellar vesicles, microfluidic technology, and micropipette aspiration are combined to continuously follow the ESCRT-III-mediated membrane remodeling on the single-vesicle level for the first time. With this approach, we identify different mechanisms by which a minimal set of three ESCRT-III proteins from Entamoeba histolytica reshape the membrane. These proteins modulate the membrane stiffness and spontaneous curvature to regulate bud size and generate intraluminal vesicles even in the absence of ATP. We demonstrate that the bud stability depends on the protein concentration and membrane tension. The approaches introduced here should open the road to diverse applications in synthetic biology for establishing artificial cells with several membrane compartments.
Collapse
Affiliation(s)
- Yunuen Avalos-Padilla
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany,Nanomalaria Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, ES-08028 Barcelona, Spain,Barcelona Institute for Global Health (ISGlobal, Hospital Clínic-Universitat de Barcelona), Rosselló 149-153, ES-08036 Barcelona, Spain
| | - Vasil N. Georgiev
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Eleanor Ewins
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Tom Robinson
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Esther Orozco
- Departamento de Infectómica y Patogénesis Molecular, CINVESTAV IPN, 07360 Ciudad de México, México
| | - Reinhard Lipowsky
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany,Corresponding author
| |
Collapse
|
3
|
Interaction of new VV-hemorphin-5 analogues with cell membrane models. Colloids Surf B Biointerfaces 2022; 220:112896. [DOI: 10.1016/j.colsurfb.2022.112896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 09/23/2022] [Accepted: 10/01/2022] [Indexed: 11/05/2022]
|
4
|
Valorphins alter physicochemical characteristics of phosphatidylcholine membranes: datasets on lipid packing, bending rigidity, specific electrical capacitance, dipole potential, vesicle size. Data Brief 2022; 45:108716. [DOI: 10.1016/j.dib.2022.108716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 10/26/2022] [Accepted: 10/28/2022] [Indexed: 11/06/2022] Open
|
5
|
Aleksanyan M, Faizi HA, Kirmpaki MA, Vlahovska PM, Riske KA, Dimova R. Assessing membrane material properties from the response of giant unilamellar vesicles to electric fields. ADVANCES IN PHYSICS: X 2022; 8:2125342. [PMID: 36211231 PMCID: PMC9536468 DOI: 10.1080/23746149.2022.2125342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023] Open
Abstract
Knowledge of the material properties of membranes is crucial to understanding cell viability and physiology. A number of methods have been developed to probe membranes in vitro, utilizing the response of minimal biomimetic membrane models to an external perturbation. In this review, we focus on techniques employing giant unilamellar vesicles (GUVs), model membrane systems, often referred to as minimal artificial cells because of the potential they offer to mimick certain cellular features. When exposed to electric fields, GUV deformation, dynamic response and poration can be used to deduce properties such as bending rigidity, pore edge tension, membrane capacitance, surface shear viscosity, excess area and membrane stability. We present a succinct overview of these techniques, which require only simple instrumentation, available in many labs, as well as reasonably facile experimental implementation and analysis.
Collapse
Affiliation(s)
- Mina Aleksanyan
- Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
- Institute for Chemistry and Biochemistry, Free University of Berlin, 14195 Berlin, Germany
| | - Hammad A. Faizi
- Department of Mechanical Engineering, Northwestern University, Evanston, IL, USA
| | - Maria-Anna Kirmpaki
- Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | - Petia M. Vlahovska
- Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, IL, USA
| | - Karin A. Riske
- Departamento de Biofísica, Universidade Federal de São Paulo, São Paulo, 04039-032 Brazil
| | - Rumiana Dimova
- Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| |
Collapse
|
6
|
Hasan S, Karal MAS, Akter S, Ahmed M, Ahamed MK, Ahammed S. Influence of sugar concentration on the vesicle compactness, deformation and membrane poration induced by anionic nanoparticles. PLoS One 2022; 17:e0275478. [PMID: 36174090 PMCID: PMC9521927 DOI: 10.1371/journal.pone.0275478] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 09/16/2022] [Indexed: 11/19/2022] Open
Abstract
Sugar plays a vital role in the structural and functional characteristics of cells. Hence, the interaction of NPs with cell membranes in the presence of sugar concentrations is important for medicinal and pharmacological innovations. This study integrated three tools: giant unilamellar vesicles (GUVs), anionic magnetite nanoparticles (NPs), and sugar concentrations, to understand a simplified mechanism for interactions between the vesicle membranes and NPs under various sugar concentrations. We focused on changing the sugar concentration in aqueous solution; more precisely, sucrose inside the GUVs and glucose outside with equal osmolarity. 1,2-dioleoyl-sn-glycero-3-phospho-(1′-rac-glycerol) (sodium salt) (DOPG) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) were used to prepare the charged membranes of 40mole%DOPG/60mole%DOPC-GUVs, whereas only DOPC was used to prepare the neutral membranes. Phase contrast fluorescence microscopy shows that the adherence of 18 nm magnetite NPs with anionic charge depends on the sugar concentration. The alterations of GUVs induced by the NPs are characterized in terms of i) vesicle compactness, ii) deformation, and iii) membrane poration. The presence of sugar provides additional structural stability to the GUVs and reduces the effects of the NPs with respect to these parameters; more precisely, the higher the sugar concentration, the smaller the alteration induced by the NPs. The differences in NPs effects are explained by the change in the type of interaction between sugar molecules and lipid membranes, namely enthalpy and entropy-driven interaction, respectively. In addition, such alterations are influenced by the surface charge density of the lipid bilayer. The surface pressure of membranes due to the adsorption of NPs is responsible for inducing the poration in membranes. The differences in deformation and poration in charged and neutral GUVs under various sugar concentrations are discussed based on the structure of the head of lipid molecules.
Collapse
Affiliation(s)
- Sharif Hasan
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Mohammad Abu Sayem Karal
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
- * E-mail:
| | - Salma Akter
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Marzuk Ahmed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Md. Kabir Ahamed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
- Radiation, Transport and Waste Safety Division, Bangladesh Atomic Energy Regulatory Authority, Dhaka, Bangladesh
| | - Shareef Ahammed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| |
Collapse
|
7
|
Faizi HA, Tsui A, Dimova R, Vlahovska PM. Bending Rigidity, Capacitance, and Shear Viscosity of Giant Vesicle Membranes Prepared by Spontaneous Swelling, Electroformation, Gel-Assisted, and Phase Transfer Methods: A Comparative Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:10548-10557. [PMID: 35993569 PMCID: PMC9671160 DOI: 10.1021/acs.langmuir.2c01402] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Closed lipid bilayers in the form of giant unilamellar vesicles (GUVs) are commonly used membrane models. Various methods have been developed to prepare GUVs, however it is unknown if all approaches yield membranes with the same elastic, electric, and rheological properties. Here, we combine flickering spectroscopy and electrodefomation of GUVs to measure, at identical conditions, membrane capacitance, bending rigidity and shear surface viscosity of palmitoyloleoylphosphatidylcholine (POPC) membranes formed by several commonly used preparation methods: thin film hydration (spontaneous swelling), electroformation, gel-assisted swelling using poly(vinyl alcohol) (PVA) or agarose, and phase-transfer. We find relatively similar bending rigidity value across all the methods except for the agarose hydration method. In addition, the capacitance values are similar except for vesicles prepared via PVA gel hydration. Intriguingly, membranes prepared by the gel-assisted and phase-transfer methods exhibit much higher shear viscosity compared to electroformation and spontaneous swelling, likely due to remnants of polymers (PVA and agarose) and oils (hexadecane and mineral) in the lipid bilayer structure.
Collapse
Affiliation(s)
- Hammad A Faizi
- Department of Mechanical Engineering, McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois 60208, United States
| | - Annie Tsui
- Department of Industrial Engineering, McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois 60208, United States
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Petia M Vlahovska
- Department of Engineering Sciences and Applied Mathematics, McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois 60208, United States
| |
Collapse
|
8
|
Sarkar MK, Karal MAS, Levadny V, Belaya M, Ahmed M, Ahamed MK, Ahammed S. Effects of sugar concentration on the electroporation, size distribution and average size of charged giant unilamellar vesicles. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2022; 51:401-412. [PMID: 35716178 DOI: 10.1007/s00249-022-01607-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 06/04/2022] [Indexed: 06/15/2023]
Abstract
We investigated the effects of sugar concentration on the electroporation, size distribution and average size of giant unilamellar vesicles (GUVs). GUVs were prepared from 40 mol% of 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DOPG) and 60 mol% of 1, 2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) lipids. Pulsed electric field was applied to the 40%DOPG/60%DOPC-GUVs and it induced lateral electric tension (σc) in the membranes of vesicles. The σc-induced probability of rupture (Ppore) and the rate constant of rupture (kp) of GUVs under the sugar concentration, c = 40, 100 and 300 mM, were determined. Both the Ppore and kp increased with the increase of σc, but higher tension was required to generate the same values of Ppore and kp with increasing c. We also investigated average sizes of GUVs from the size distribution of vesicles under various sugar concentrations. With the increase of c, the peak of the size distribution histograms shifted to the region of smaller vesicles. The average size decreased 1.6-fold when c increased from 10 to 300 mM. These investigations help to understand various biomedical, biophysical, and biochemical processes in vesicles and cells. Electroporation, size distribution and average size of charged GUVs were investigated under various sugar concentrations. The sugar concentration influences the electroporation of vesicles and the average size of GUVs.
Collapse
Affiliation(s)
- Malay Kumar Sarkar
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh
- Department of Arts and Sciences, Ahsanullah University of Science and Technology, Dhaka, 1208, Bangladesh
| | - Mohammad Abu Sayem Karal
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh.
| | - Victor Levadny
- Theoretical Problem Center of Physico-Chemical Pharmacology, Russian Academy of Sciences, Moscow, 117977, Russia
| | - Marina Belaya
- Department of Mathematics, Russian State University for the Humanities, GSP-3, Moscow, 125993, Russia
| | - Marzuk Ahmed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh
| | - Md Kabir Ahamed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh
| | - Shareef Ahammed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh
| |
Collapse
|
9
|
Vitkova V, Yordanova V, Staneva G, Petkov O, Stoyanova-Ivanova A, Antonova K, Popkirov G. Dielectric Properties of Phosphatidylcholine Membranes and the Effect of Sugars. MEMBRANES 2021; 11:membranes11110847. [PMID: 34832076 PMCID: PMC8623822 DOI: 10.3390/membranes11110847] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/25/2021] [Accepted: 10/27/2021] [Indexed: 11/16/2022]
Abstract
Simple carbohydrates are associated with the enhanced risk of cardiovascular disease and adverse changes in lipoproteins in the organism. Conversely, sugars are known to exert a stabilizing effect on biological membranes, and this effect is widely exploited in medicine and industry for cryopreservation of tissues and materials. In view of elucidating molecular mechanisms involved in the interaction of mono- and disaccharides with biomimetic lipid systems, we study the alteration of dielectric properties, the degree of hydration, and the rotational order parameter and dipole potential of lipid bilayers in the presence of sugars. Frequency-dependent deformation of cell-size unilamellar lipid vesicles in alternating electric fields and fast Fourier transform electrochemical impedance spectroscopy are applied to measure the specific capacitance of phosphatidylcholine lipid bilayers in sucrose, glucose and fructose aqueous solutions. Alteration of membrane specific capacitance is reported in sucrose solutions, while preservation of membrane dielectric properties is established in the presence of glucose and fructose. We address the effect of sugars on the hydration and the rotational order parameter for 1-palmitoyl-2-oleoyl-sn-glycero-3- phosphocholine (POPC) and 1-stearoyl-2-oleoyl-sn-glycero-3- phosphocholine (SOPC). An increased degree of lipid packing is reported in sucrose solutions. The obtained results provide evidence that some small carbohydrates are able to change membrane dielectric properties, structure, and order related to membrane homeostasis. The reported data are also relevant to future developments based on the response of lipid bilayers to external physical stimuli such as electric fields and temperature changes.
Collapse
Affiliation(s)
- Victoria Vitkova
- Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria; (O.P.); (A.S.-I.); (K.A.)
- Correspondence:
| | - Vesela Yordanova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria; (V.Y.); (G.S.)
| | - Galya Staneva
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria; (V.Y.); (G.S.)
| | - Ognyan Petkov
- Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria; (O.P.); (A.S.-I.); (K.A.)
| | - Angelina Stoyanova-Ivanova
- Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria; (O.P.); (A.S.-I.); (K.A.)
| | - Krassimira Antonova
- Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria; (O.P.); (A.S.-I.); (K.A.)
| | - Georgi Popkirov
- Central Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Blvd., 1784 Sofia, Bulgaria;
| |
Collapse
|
10
|
Faizi HA, Dimova R, Vlahovska PM. Electromechanical characterization of biomimetic membranes using electrodeformation of vesicles. Electrophoresis 2021; 42:2027-2032. [PMID: 34297846 DOI: 10.1002/elps.202100091] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 07/01/2021] [Accepted: 07/09/2021] [Indexed: 11/08/2022]
Abstract
We describe a facile method to simultaneously measure the bending rigidity and capacitance of biomimetic lipid bilayers. Our approach utilizes the ellipsoidal deformation of quasi-spherical giant unilamellar vesicles induced by a uniform AC electric field. Vesicle shape depends on the electric field frequency and amplitude. Membrane bending rigidity can be obtained from the variation of the vesicle elongation on either field amplitude at fixed frequency or frequency at fixed field amplitude. Membrane capacitance is determined from the frequency at which the vesicle shape changes from prolate to oblate ellipsoid as the frequency is increased at a given field amplitude.
Collapse
Affiliation(s)
- Hammad A Faizi
- Department of Mechanical Engineering, Northwestern University, Evanston, IL, USA
| | - Rumiana Dimova
- Department of Theory and Biosystems, Max Planck Institute of Colloids and Interfaces, Science Park Golm, Potsdam, Germany
| | - Petia M Vlahovska
- Department of Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, IL, USA
| |
Collapse
|
11
|
Hayashi K, Sugimura H, Kamei T, Shimanouchi T, Nakamura H, Umakoshi H. Quantitative Determination of Relative Permittivity Based on the Fluorescence Property of Pyrene Derivatives: An Interpretation of Hydrophobicity in Self-Assembled Aggregates of Nonionic Amphiphiles. J Phys Chem B 2021; 125:6192-6200. [PMID: 34077661 DOI: 10.1021/acs.jpcb.1c00170] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Aggregates in aqueous solutions can embed hydrophobic molecules, and their interactions depend on the properties of the aggregates. The electric surface potential, molecular mobility, and gradual hydrophobicity are the properties that regulate the interactions, and it is essential to understand these to quantify the properties. Electric surface potential and molecular mobility are quantified using the zeta potential and NMR measurements. In this study, the quantification of gradual hydrophobicity within the aggregate based on the relative permittivity, also called the dielectric constant, has been estimated from fluorescence spectra of pyrene-dicarboxylic acid conjugates. The localization of the pyrene moiety was modified by conjugation with succinic acid, suberic acid, or dodecanedioic acid, and the conjugates were evaluated in the shallow, middle, and deep regions of the aggregates. Span and Tween surfactants have been employed to prepare these aggregates, because they form various kinds of aggregates such as micelles and vesicles. It was realized that the hydrophobicity gradually increased from the interface to the hydrophobic core. Alternatively, a comparison of hydrophobicity within the aggregates showed no remarkable difference. Moreover, the analyses suggested that there are a few water molecules in the deep region. These results support the idea of the localization of embedded molecules in aggregates.
Collapse
Affiliation(s)
- Keita Hayashi
- Department of Chemical Engineering, National Institute of Technology, Nara College, 22 Yata-cho, Yamatokoriyama, Nara 639-1080, Japan
| | - Haruna Sugimura
- Department of Chemical Engineering, National Institute of Technology, Nara College, 22 Yata-cho, Yamatokoriyama, Nara 639-1080, Japan
| | - Toshiyuki Kamei
- Department of Chemical Engineering, National Institute of Technology, Nara College, 22 Yata-cho, Yamatokoriyama, Nara 639-1080, Japan
| | - Toshinori Shimanouchi
- Graduate School of Environmental and Life Science, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan
| | - Hidemi Nakamura
- Department of Chemical Engineering, National Institute of Technology, Nara College, 22 Yata-cho, Yamatokoriyama, Nara 639-1080, Japan
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
12
|
Ortega G, Kurnik M, Gautam BK, Plaxco KW. Attachment of Proteins to a Hydroxyl-Terminated Surface Eliminates the Stabilizing Effects of Polyols. J Am Chem Soc 2020; 142:15349-15354. [PMID: 32786756 DOI: 10.1021/jacs.0c05719] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The physics of proteins interacting with surfaces can differ significantly from those seen when the same proteins are free in bulk solution. As an example, we describe here the extent to which site-specific attachment to a chemically well-defined macroscopic surface alters the ability of several stabilizing and destabilizing cosolutes to modulate protein folding thermodynamics. We determined this via guanidinium denaturations performed in the presence of varying concentrations of cosolutes when proteins were either site-specifically attached to self-assembled monolayers on gold or free in bulk solution. Doing this we found that the extent to which guanidinium (a destabilizing Hofmeister cation), sulfate (a stabilizing Hofmeister anion), and urea (a neutral denaturant) alter the folding free energy remains indistinguishable whether proteins are surface-attached or free in bulk solution. In sharp contrast, however, neutral osmolytes sucrose and glycerol, which significantly stabilize proteins in bulk solution, do not measurably affect their stability when they are attached to a hydroxyl-terminated surface. In contrast, we recovered bulk solution-like stabilization when the attachment surface was instead carboxyl-terminated. It thus appears that chemistry-specific surface interactions can dramatically alter the way in which biomolecules interact with other components of the system.
Collapse
Affiliation(s)
- Gabriel Ortega
- Department of Chemistry and Biochemistry, University of California-Santa Barbara, Santa Barbara, California 93106, United States.,Center for Bioengineering, University of California-Santa Barbara, Santa Barbara, California 93106, United States
| | - Martin Kurnik
- Department of Chemistry and Biochemistry, University of California-Santa Barbara, Santa Barbara, California 93106, United States.,Center for Bioengineering, University of California-Santa Barbara, Santa Barbara, California 93106, United States
| | - Bishal K Gautam
- Department of Chemistry and Biochemistry, University of California-Santa Barbara, Santa Barbara, California 93106, United States
| | - Kevin W Plaxco
- Department of Chemistry and Biochemistry, University of California-Santa Barbara, Santa Barbara, California 93106, United States.,Center for Bioengineering, University of California-Santa Barbara, Santa Barbara, California 93106, United States
| |
Collapse
|
13
|
Abstract
Vesicle structures primarily embody spherical capsules composed of a single or multiple bilayers, entrapping a pool of aqueous solution in their interior. The bilayers can be synthesised by phospholipids or other amphiphiles (surfactants, block copolymers, etc.). Vesicles with broad-spectrum applications in numerous scientific disciplines, including biochemistry, biophysics, biology, and various pharmaceutical industries, have attracted widespread attention. Consequently, a multitude of protocols have been devised and proposed for their fabrication. In this review, with a motivation to derive the basic conditions for the formation of vesicles, the associated thermodynamic and kinetic aspects are comprehensively appraised. Contextually, an all-purpose overview of the underlying thermodynamics of bilayer/membrane generation and deformation, including the chemical potential of aggregates, geometric packing and the concept of elastic properties, is presented. Additionally, the current review highlights the probable, inherent mechanisms of vesicle formation under distinct modes of manufacturing. We lay focus on vesicle formation from pre-existing bilayers, as well as from bilayers, which form when lipids from an organic solvent are transferred into an aqueous medium. Furthermore, we outline the kinetic effects on vesicle formation from the lamellar phase, with and without the presence of shearing force. Wherever required, the experimental and/or theoretical outcomes, the driving forces for vesicle size selection, and various scaling laws are also reviewed, all of which facilitate an overall improved understanding of the vesicle formation mechanisms.
Collapse
Affiliation(s)
- Chandra Has
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Sharadwata Pan
- School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| |
Collapse
|
14
|
Volatile and semi-volatile compounds of Tephrosia purpurea and its medicinal activities: Experimental and computational studies. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.101222] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
|
15
|
Dimova R. Giant Vesicles and Their Use in Assays for Assessing Membrane Phase State, Curvature, Mechanics, and Electrical Properties. Annu Rev Biophys 2019; 48:93-119. [DOI: 10.1146/annurev-biophys-052118-115342] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Giant unilamellar vesicles represent a promising and extremely useful model biomembrane system for systematic measurements of mechanical, thermodynamic, electrical, and rheological properties of lipid bilayers as a function of membrane composition, surrounding media, and temperature. The most important advantage of giant vesicles over other model membrane systems is that the membrane responses to external factors such as ions, (macro)molecules, hydrodynamic flows, or electromagnetic fields can be directly observed under the microscope. Here, we briefly review approaches for giant vesicle preparation and describe several assays used for deducing the membrane phase state and measuring a number of material properties, with further emphasis on membrane reshaping and curvature.
Collapse
Affiliation(s)
- Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| |
Collapse
|
16
|
Todorov PT, Peneva PN, Georgieva SI, Tchekalarova J, Vitkova V, Antonova K, Georgiev A. Synthesis, characterization and anticonvulsant activity of new azobenzene-containing VV-hemorphin-5 bio photoswitch. Amino Acids 2019; 51:549-563. [PMID: 30604096 DOI: 10.1007/s00726-018-02691-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 12/20/2018] [Indexed: 11/30/2022]
Abstract
A novel analog of VV-hemorphin-5 containing azobenzene moiety has been synthesized and investigated for anticonvulsant activity in relation to its E → Z photophysical properties activated by long wavelength light at 365 nm. The synthesis was achieved by a modified SPPS by Fmoc-dimerization strategy. The electrochemical behavior before and after UV illumination was investigated using different voltammetric modes. The number of electrons transferred, heterogenic rate constant and diffusion coefficient for E- and Z-isomers were also evaluated. Revealing the governing principles involved in signaling and nerve pulse propagation requires the detailed characterization of the electrical properties of cell membranes. For probing the effect of synthesized azo-peptide on the membrane electrical properties, we measured the specific capacitance of lipid bilayers, representing a basic physical model of biomembranes with their simple reproducibility in laboratory conditions at controlled membrane composition and physicochemical parameters of the surrounding aqueous medium. Our results have shown reduced membrane capacitance in the presence of the azo-peptide, thus providing evidences for possible alterations in the dielectric permittivity of the bilayer. The (Val-Val-Tyr-Pro-Trp-Thr-Gln)2Azo peptide was explored also in vivo for preliminary anticonvulsant activity by using the 6-Hz seizure test and pentylenetetrazol (PTZ) seizure test in mice. The Z-isomer has exhibited higher potency compared to E-isomer most pronouncedly in the 6 Hz test for psychomotor seizures where the compound had activity at all three tested doses. It was found that the Z-isomer decrease the latency for onset of clonic seizures induced by PTZ. These results demonstrate that the Z-isomer deserves further evaluation in other screening tests for anticonvulsant activity.
Collapse
Affiliation(s)
- Petar T Todorov
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756, Sofia, Bulgaria.
| | - Petia N Peneva
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756, Sofia, Bulgaria
| | - Stela I Georgieva
- Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 1756, Sofia, Bulgaria
| | - Jana Tchekalarova
- Institute of Neurobiology, Bulgarian Academy of Sciences, 1113, Sofia, Bulgaria
| | - Victoria Vitkova
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784, Sofia, Bulgaria
| | - Krassimira Antonova
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784, Sofia, Bulgaria
| | - Anton Georgiev
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756, Sofia, Bulgaria.,Department of Optical Metrology and Holography, Institute of Optical Materials and Technologies, Bulgarian Academy of Science, 1113, Sofia, Bulgaria
| |
Collapse
|