1
|
Mangiarotti A, Aleksanyan M, Siri M, Sun T, Lipowsky R, Dimova R. Photoswitchable Endocytosis of Biomolecular Condensates in Giant Vesicles. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2309864. [PMID: 38582523 PMCID: PMC11187966 DOI: 10.1002/advs.202309864] [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: 12/15/2023] [Revised: 03/14/2024] [Indexed: 04/08/2024]
Abstract
Interactions between membranes and biomolecular condensates can give rise to complex phenomena such as wetting transitions, mutual remodeling, and endocytosis. In this study, light-triggered manipulation of condensate engulfment is demonstrated using giant vesicles containing photoswitchable lipids. UV irradiation increases the membrane area, which can be stored in nanotubes. When in contact with a condensate droplet, the UV light triggers rapid condensate endocytosis, which can be reverted by blue light. The affinity of the protein-rich condensates to the membrane and the reversibility of the engulfment processes is quantified from confocal microscopy images. The degree of photo-induced engulfment, whether partial or complete, depends on the vesicle excess area and the relative sizes of vesicles and condensates. Theoretical estimates suggest that utilizing the light-induced excess area to increase the vesicle-condensate adhesion interface is energetically more favorable than the energy gain from folding the membrane into invaginations and tubes. The overall findings demonstrate that membrane-condensate interactions can be easily and quickly modulated via light, providing a versatile system for building platforms to control cellular events and design intelligent drug delivery systems for cell repair.
Collapse
Affiliation(s)
- Agustín Mangiarotti
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
| | - Mina Aleksanyan
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
- Institute for Chemistry and BiochemistryFree University of BerlinTakustraße 314195BerlinGermany
| | - Macarena Siri
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
- Max Planck Queensland CentreScience Park Golm14476PotsdamGermany
| | - Tsu‐Wang Sun
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
| | - Reinhard Lipowsky
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
| | - Rumiana Dimova
- Max Planck Institute of Colloids and InterfacesScience Park Golm14476PotsdamGermany
| |
Collapse
|
2
|
van der Ham S, Agudo-Canalejo J, Vutukuri HR. Role of Shape in Particle-Lipid Membrane Interactions: From Surfing to Full Engulfment. ACS NANO 2024; 18:10407-10416. [PMID: 38513125 PMCID: PMC11025115 DOI: 10.1021/acsnano.3c11106] [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: 11/09/2023] [Revised: 03/08/2024] [Accepted: 03/13/2024] [Indexed: 03/23/2024]
Abstract
Understanding and manipulating the interactions between foreign bodies and cell membranes during endo- and phagocytosis is of paramount importance, not only for the fate of living cells but also for numerous biomedical applications. This study aims to elucidate the role of variables such as anisotropic particle shape, curvature, orientation, membrane tension, and adhesive strength in this essential process using a minimal experimental biomimetic system comprising giant unilamellar vesicles and rod-like particles with different curvatures and aspect ratios. We find that the particle wrapping process is dictated by the balance between the elastic free energy penalty and adhesion free energy gain, leading to two distinct engulfment pathways, tip-first and side-first, emphasizing the significance of the particle orientation in determining the pathway. Moreover, our experimental results are consistent with theoretical predictions in a state diagram, showcasing how to control the wrapping pathway from surfing to partial to complete wrapping by the interplay between membrane tension and adhesive strength. At moderate particle concentrations, we observed the formation of rod clusters, which exhibited cooperative and sequential wrapping. Our study contributes to a comprehensive understanding of the mechanistic intricacies of endocytosis by highlighting how the interplay between the anisotropic particle shape, curvature, orientation, membrane tension, and adhesive strength can influence the engulfment pathway.
Collapse
Affiliation(s)
- Stijn van der Ham
- Active
Soft Matter and Bio-inspired Materials Lab, Faculty of Science and
Technology, MESA+ Institute, University
of Twente, 7500 AE Enschede, The Netherlands
| | - Jaime Agudo-Canalejo
- Department
of Living Matter Physics, Max Planck Institute
for Dynamics and Self-Organization, Göttingen, D-37077, Germany
- Department
of Physics and Astronomy, University College
London, London WC1E 6BT, United Kingdom
| | - Hanumantha Rao Vutukuri
- Active
Soft Matter and Bio-inspired Materials Lab, Faculty of Science and
Technology, MESA+ Institute, University
of Twente, 7500 AE Enschede, The Netherlands
| |
Collapse
|
3
|
Van de Cauter L, van Buren L, Koenderink GH, Ganzinger KA. Exploring Giant Unilamellar Vesicle Production for Artificial Cells - Current Challenges and Future Directions. SMALL METHODS 2023; 7:e2300416. [PMID: 37464561 DOI: 10.1002/smtd.202300416] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/30/2023] [Indexed: 07/20/2023]
Abstract
Creating an artificial cell from the bottom up is a long-standing challenge and, while significant progress has been made, the full realization of this goal remains elusive. Arguably, one of the biggest hurdles that researchers are facing now is the assembly of different modules of cell function inside a single container. Giant unilamellar vesicles (GUVs) have emerged as a suitable container with many methods available for their production. Well-studied swelling-based methods offer a wide range of lipid compositions but at the expense of limited encapsulation efficiency. Emulsion-based methods, on the other hand, excel at encapsulation but are only effective with a limited set of membrane compositions and may entrap residual additives in the lipid bilayer. Since the ultimate artificial cell will need to comply with both specific membrane and encapsulation requirements, there is still no one-method-fits-all solution for GUV formation available today. This review discusses the state of the art in different GUV production methods and their compatibility with GUV requirements and operational requirements such as reproducibility and ease of use. It concludes by identifying the most pressing issues and proposes potential avenues for future research to bring us one step closer to turning artificial cells into a reality.
Collapse
Affiliation(s)
- Lori Van de Cauter
- Autonomous Matter Department, AMOLF, Amsterdam, 1098 XG, The Netherlands
| | - Lennard van Buren
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2629 HZ, The Netherlands
| | - Gijsje H Koenderink
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2629 HZ, The Netherlands
| | | |
Collapse
|
4
|
Krok E, Stephan M, Dimova R, Piatkowski L. Tunable biomimetic bacterial membranes from binary and ternary lipid mixtures and their application in antimicrobial testing. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184194. [PMID: 37328023 DOI: 10.1016/j.bbamem.2023.184194] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 06/05/2023] [Accepted: 06/08/2023] [Indexed: 06/18/2023]
Abstract
The reconstruction of accurate yet simplified mimetic models of cell membranes is a very challenging goal of synthetic biology. To date, most of the research focuses on the development of eukaryotic cell membranes, while reconstitution of their prokaryotic counterparts has not been fully addressed, and the proposed models do not reflect well the complexity of bacterial cell envelopes. Here, we describe the reconstitution of biomimetic bacterial membranes with an increasing level of complexity, developed from binary and ternary lipid mixtures. Giant unilamellar vesicles composed of phosphatidylcholine (PC) and phosphatidylethanolamine (PE); PC and phosphatidylglycerol (PG); PE and PG; PE, PG and cardiolipin (CA) at varying molar ratios were successfully prepared by the electroformation method. Each of the proposed mimetic models focuses on reproducing specific membrane features such as membrane charge, curvature, leaflets asymmetry, or the presence of phase separation. GUVs were characterized in terms of size distribution, surface charge, and lateral organization. Finally, the developed models were tested against the lipopeptide antibiotic daptomycin. The obtained results showed a clear dependency of daptomycin binding efficiency on the amount of negatively charged lipid species present in the membrane. We anticipate that the models proposed here can be applied not only in antimicrobial testing but also serve as platforms for studying fundamental biological processes in bacteria as well as their interaction with physiologically relevant biomolecules.
Collapse
Affiliation(s)
- Emilia Krok
- Poznan University of Technology, Faculty of Materials Engineering and Technical Physics, Institute of Physics, Piotrowo 3, 60-965 Poznan, Poland; Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany.
| | - Mareike Stephan
- 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.
| | - Lukasz Piatkowski
- Poznan University of Technology, Faculty of Materials Engineering and Technical Physics, Institute of Physics, Piotrowo 3, 60-965 Poznan, Poland
| |
Collapse
|
5
|
Abelenda-Núñez I, Ortega F, Rubio RG, Guzmán E. Anomalous Colloidal Motion under Strong Confinement. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2302115. [PMID: 37116105 DOI: 10.1002/smll.202302115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 04/13/2023] [Indexed: 06/19/2023]
Abstract
Diffusion of biological macromolecules in the cytoplasm is a paradigm of colloidal diffusion in an environment characterized by a strong restriction of the accessible volume. This makes of the understanding of the physical rules governing colloidal diffusion under conditions mimicking the reduction in accessible volume occurring in the cell cytoplasm, a problem of a paramount importance. This work aims to study how the thermal motion of spherical colloidal beads in the inner cavity of giant unilamellar vesicles (GUVs) is modified by strong confinement conditions, and the viscoelastic character of the medium. Using single particle tracking, it is found that both the confinement and the environmental viscoelasticity lead to the emergence of anomalous motion pathways for colloidal microbeads encapsulated in the aqueous inner cavity of GUVs. This anomalous diffusion is strongly dependent on the ratio between the volume of the colloidal particle and that of the GUV under consideration as well as on the viscosity of the particle's liquid environment. Therefore, the results evidence that the reduction of the free volume accessible to colloidal motion pushes the diffusion far from a standard Brownian pathway as a result of the change in the hydrodynamic boundary conditions driving the particle motion.
Collapse
Affiliation(s)
- Irene Abelenda-Núñez
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n., Madrid, 28040, Spain
| | - Francisco Ortega
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n., Madrid, 28040, Spain
- Unidad de Materia Condensada, Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII 1., Madrid, 28040, Spain
| | - Ramón G Rubio
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n., Madrid, 28040, Spain
| | - Eduardo Guzmán
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n., Madrid, 28040, Spain
- Unidad de Materia Condensada, Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII 1., Madrid, 28040, Spain
| |
Collapse
|
6
|
Yu K, Jiang Y, Chen Y, Hu X, Chang J, Hartland GV, Wang GP. Compressible viscoelasticity of cell membranes determined by gigahertz-frequency acoustic vibrations. PHOTOACOUSTICS 2023; 31:100494. [PMID: 37131996 PMCID: PMC10149280 DOI: 10.1016/j.pacs.2023.100494] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/09/2023] [Accepted: 04/11/2023] [Indexed: 05/04/2023]
Abstract
Membrane viscosity is an important property of cell biology, which determines cellular function, development and disease progression. Various experimental and computational methods have been developed to investigate the mechanics of cells. However, there have been no experimental measurements of the membrane viscosity at high-frequencies in live cells. High frequency measurements are important because they can probe viscoelastic effects. Here, we investigate the membrane viscosity at gigahertz-frequencies through the damping of the acoustic vibrations of gold nanoplates. The experiments are modeled using a continuum mechanics theory which reveals that the membranes display viscoelasticity, with an estimated relaxation time of ca. 5.7 + 2.4 / - 2.7 ps. We further demonstrate that membrane viscoelasticity can be used to differentiate a cancerous cell line (the human glioblastoma cells LN-18) from a normal cell line (the mouse brain microvascular endothelial cells bEnd.3). The viscosity of cancerous cells LN-18 is lower than that of healthy cells bEnd.3 by a factor of three. The results indicate promising applications of characterizing membrane viscoelasticity at gigahertz-frequency in cell diagnosis.
Collapse
Affiliation(s)
- Kuai Yu
- State Key Laboratory of Radio Frequency Heterogeneous Integration, College of Electronics and Information Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yiqi Jiang
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Yungao Chen
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Xiaoyan Hu
- Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Junlei Chang
- Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Gregory V. Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Guo Ping Wang
- State Key Laboratory of Radio Frequency Heterogeneous Integration, College of Electronics and Information Engineering, Shenzhen University, Shenzhen 518060, China
- Corresponding author.
| |
Collapse
|
7
|
Eremchev M, Roesel D, Dansette PM, Michailovas A, Roke S. High throughput wide field second harmonic imaging of giant unilamellar vesicles. Biointerphases 2023; 18:031202. [PMID: 37289033 DOI: 10.1116/6.0002640] [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: 03/05/2023] [Accepted: 05/16/2023] [Indexed: 06/09/2023] Open
Abstract
Cell-sized giant unilamellar vesicles (GUVs) are an ideal tool for understanding lipid membrane structure and properties. Label-free spatiotemporal images of their membrane potential and structure would greatly aid the quantitative understanding of membrane properties. In principle, second harmonic imaging is a great tool to do so, but the low degree of spatial anisotropy that arises from a single membrane limits its application. Here, we advance the use of wide-field high throughput SH imaging by SH imaging with the use of ultrashort laser pulses. We achieve a throughput improvement of 78% of the maximum theoretical value and demonstrate subsecond image acquisition times. We show how the interfacial water intensity can be converted into a quantitative membrane potential map. Finally, for GUV imaging, we compare this type of nonresonant SH imaging to resonant SH imaging and two photon imaging using fluorophores.
Collapse
Affiliation(s)
- M Eremchev
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineerinsg (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - D Roesel
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineerinsg (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - P-M Dansette
- Ekspla Ltd., Savanoriu Ave. 237, LT-02300 Vilnius, Lithuania
| | - A Michailovas
- Ekspla Ltd., Savanoriu Ave. 237, LT-02300 Vilnius, Lithuania
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, LT-02300 Vilnius, Lithuania
| | - S Roke
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineerinsg (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering (IMX), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Lausanne Centre for Ultrafast Science, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| |
Collapse
|
8
|
Krompers M, Heerklotz H. A Guide to Your Desired Lipid-Asymmetric Vesicles. MEMBRANES 2023; 13:267. [PMID: 36984654 PMCID: PMC10054703 DOI: 10.3390/membranes13030267] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/14/2023] [Accepted: 02/18/2023] [Indexed: 06/18/2023]
Abstract
Liposomes are prevalent model systems for studies on biological membranes. Recently, increasing attention has been paid to models also representing the lipid asymmetry of biological membranes. Here, we review in-vitro methods that have been established to prepare free-floating vesicles containing different compositions of the classic two-chain glycero- or sphingolipids in their outer and inner leaflet. In total, 72 reports are listed and assigned to four general strategies that are (A) enzymatic conversion of outer leaflet lipids, (B) re-sorting of lipids between leaflets, (C) assembly from different monolayers and (D) exchange of outer leaflet lipids. To guide the reader through this broad field of available techniques, we attempt to draw a road map that leads to the lipid-asymmetric vesicles that suit a given purpose. Of each method, we discuss advantages and limitations. In addition, various verification strategies of asymmetry as well as the role of cholesterol are briefly discussed. The ability to specifically induce lipid asymmetry in model membranes offers insights into the biological functions of asymmetry and may also benefit the technical applications of liposomes.
Collapse
Affiliation(s)
- Mona Krompers
- Department of Pharmaceutical Technology and Biopharmacy, Institute for Pharmaceutical Sciences, University of Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Heiko Heerklotz
- Department of Pharmaceutical Technology and Biopharmacy, Institute for Pharmaceutical Sciences, University of Freiburg, 79104 Freiburg im Breisgau, Germany
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
- Signalling Research Centers BIOSS and CIBSS, University of Freiburg, 79085 Freiburg im Breisgau, Germany
| |
Collapse
|
9
|
Bazazi P, Stone HA, Hejazi SH. Dynamics of Droplet Pinch-Off at Emulsified Oil-Water Interfaces: Interplay between Interfacial Viscoelasticity and Capillary Forces. PHYSICAL REVIEW LETTERS 2023; 130:034001. [PMID: 36763387 DOI: 10.1103/physrevlett.130.034001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 10/16/2022] [Accepted: 12/20/2022] [Indexed: 06/18/2023]
Abstract
The presence of submicrometer structures at liquid-fluid interfaces modifies the properties of many science and technological systems by lowering the interfacial tension, creating tangential Marangoni stresses, and/or inducing surface viscoelasticity. Here we experimentally study the break-up of a liquid filament of a silica nanoparticle dispersion in a background oil phase that contains surfactant assemblies. Although self-similar power-law pinch-off is well documented for threads of Newtonian fluids, we report that when a viscoelastic layer is formed in situ at the interface, the pinch-off dynamics follows an exponential decay. Recently, such exponential neck thinning was found theoretically when surface viscous effects were taken into account. We introduce a simple approach to calculate the effective relaxation time of viscoelastic interfaces and estimate the thickness of the interfacial layer and the viscoelastic properties of liquid-fluid interfaces, where the direct measurement of interfacial rheology is not possible.
Collapse
Affiliation(s)
- Parisa Bazazi
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N, Canada
| | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - S Hossein Hejazi
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N, Canada
| |
Collapse
|
10
|
Ayala YA, Omidvar R, Römer W, Rohrbach A. Thermal fluctuations of the lipid membrane determine particle uptake into Giant Unilamellar Vesicles. Nat Commun 2023; 14:65. [PMID: 36599837 PMCID: PMC9813155 DOI: 10.1038/s41467-022-35302-5] [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: 03/29/2022] [Accepted: 11/25/2022] [Indexed: 01/06/2023] Open
Abstract
Phagocytic particle uptake is crucial for the fate of both living cells and pathogens. Invading particles have to overcome fluctuating lipid membranes as the first physical barrier. However, the energy and the role of the fluctuation-based particle-membrane interactions during particle uptake are not understood. We tackle this problem by indenting the membrane of differently composed Giant Unilamellar Vesicles (GUVs) with optically trapped particles until particle uptake. By continuous 1 MHz tracking and autocorrelating the particle's positions within 30µs delays for different indentations, the fluctuations' amplitude, the damping, the mean forces, and the energy profiles were obtained. Remarkably, the uptake energy into a GUV becomes predictable since it increases for smaller fluctuation amplitudes and longer relaxation time. Our observations could be explained by a mathematical model based on continuous suppression of fluctuation modes. Hence, the reduced particle uptake energy for protein-ligand interactions LecA-Gb3 or Biotin-Streptavidin results also from pronounced, low-friction membrane fluctuations.
Collapse
Affiliation(s)
- Yareni A Ayala
- Laboratory for Bio- and Nano-Photonics, Department of Microsystems Engineering - IMTEK, University of Freiburg, Georges-Köhler-Allee 102, 79110, Freiburg, Germany
| | - Ramin Omidvar
- Faculty of Biology, University of Freiburg, Schänzlestraße 1, 79104, Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestraße 18, 79104, Freiburg, Germany
| | - Winfried Römer
- Faculty of Biology, University of Freiburg, Schänzlestraße 1, 79104, Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestraße 18, 79104, Freiburg, Germany.,Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, Albertstraße 19, 79104, Freiburg, Germany
| | - Alexander Rohrbach
- Laboratory for Bio- and Nano-Photonics, Department of Microsystems Engineering - IMTEK, University of Freiburg, Georges-Köhler-Allee 102, 79110, Freiburg, Germany. .,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestraße 18, 79104, Freiburg, Germany.
| |
Collapse
|
11
|
Doğan Güzel F, Kaur J, Zendeh Z. Cheap portable electroformed giant unilamellar vesicles preparation kit. J Liposome Res 2022:1-6. [DOI: 10.1080/08982104.2022.2149777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Fatma Doğan Güzel
- Department of Biomedical Engineering, Faculty of Engineering and Natural Sciences, Ankara Yıldırım Beyazıt University, Ankara, Turkey
| | - Jaspreet Kaur
- Department of Electrical and Electronic Engineering, Faculty of Engineering and Natural Sciences, Ankara Yıldırım Beyazıt University, Ankara, Turkey
| | - Zahra Zendeh
- Department of Translational Medicine, Faculty of Medicine, Ankara Yıldırım Beyazıt University, Ankara, Turkey
| |
Collapse
|
12
|
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
|
13
|
Pritzl SD, Morstein J, Kahler S, Konrad DB, Trauner D, Lohmüller T. Postsynthetic Photocontrol of Giant Liposomes via Fusion-Based Photolipid Doping. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:11941-11949. [PMID: 36130117 PMCID: PMC9536078 DOI: 10.1021/acs.langmuir.2c01685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 09/06/2022] [Indexed: 06/15/2023]
Abstract
We report on photolipid doping of giant unilamellar vesicles (GUVs) via vesicle fusion with small unilamellar photolipid vesicles (pSUVs), which enables retroactive optical control of the membrane properties. We observe that vesicle fusion is light-dependent, if the phospholipids are neutral. Charge-mediated fusion involving anionic and cationic lipid molecules augments the overall fusion performance and doping efficiency, even in the absence of light exposure. Using phosphatidylcholine analogs with one or two azobenzene photoswitches (azo-PC and dazo-PC) affects domain formation, bending stiffness, and shape of the resulting vesicles in response to irradiation. Moreover, we show that optical membrane control can be extended to long wavelengths using red-absorbing photolipids (red-azo-PC). Combined, our findings present an attractive and practical method for the precise delivery of photolipids, which offers new prospects for the optical control of membrane function.
Collapse
Affiliation(s)
- Stefanie D. Pritzl
- Chair
for Photonics and Optoelectronics, Nano-Institute Munich, Department
of Physics, Ludwig-Maximilians-Universität
(LMU), 80539 Munich, Germany
| | - Johannes Morstein
- Department
of Chemistry, New York University, Silver Center, New York 10003, United States
- Department
of Cellular and Molecular Pharmacology, UCSF, San Francisco, California 94143, United States
| | - Sophia Kahler
- Department
of Chemistry, New York University, Silver Center, New York 10003, United States
| | - David B. Konrad
- Department
of Pharmacy, Ludwig-Maximilians-Universität
(LMU), 81377 Munich, Germany
| | - Dirk Trauner
- Department
of Chemistry, New York University, Silver Center, New York 10003, United States
| | - Theobald Lohmüller
- Chair
for Photonics and Optoelectronics, Nano-Institute Munich, Department
of Physics, Ludwig-Maximilians-Universität
(LMU), 80539 Munich, Germany
| |
Collapse
|
14
|
Xiao K, Ma R, Wu CX. Force-induced wrapping phase transition in activated cellular uptake. Phys Rev E 2022; 106:044411. [PMID: 36397463 DOI: 10.1103/physreve.106.044411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
Intracellular pathogens, including all viruses and many bacteria, enter a host cell through either passive endocytosis or active self-propulsion. Though the cellular uptake of passive particles via endocytic process has been studied extensively, little work has been done on the active entry of self-propelled pathogens, such as Listeria monocytogenes. Here, we present a theoretical model to investigate the adhesive wrapping of a self-propelled particle by a plasma membrane, and find a type of first-order wrapping transition from a small partial wrapping state to a large partial wrapping state triggered by the active force. The phase diagram displays more complex behaviors compared with the passive wrapping mediated merely by adhesion. We also find that a tubular protrusion can be formed if the active force exceeds a force barrier. These results may provide a useful guidance to the study of activity-driven cellular entry of active particles into cells.
Collapse
Affiliation(s)
- Ke Xiao
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325016, People's Republic of China and Department of Physics, College of Physical Science and Technology, Xiamen University, Xiamen 361005, People's Republic of China
| | - Rui Ma
- Fujian Provincial Key Lab for Soft Functional Materials Research, Research Institute for Biomimetics and Soft Matter, Department of Physics, College of Physical Science and Technology, Xiamen University, Xiamen 361005, People's Republic of China
| | - Chen-Xu Wu
- Fujian Provincial Key Lab for Soft Functional Materials Research, Research Institute for Biomimetics and Soft Matter, Department of Physics, College of Physical Science and Technology, Xiamen University, Xiamen 361005, People's Republic of China
| |
Collapse
|
15
|
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
|
16
|
Altunayar-Unsalan C, Unsalan O, Mavromoustakos T. Molecular interactions of hesperidin with DMPC/cholesterol bilayers. Chem Biol Interact 2022; 366:110131. [PMID: 36037876 DOI: 10.1016/j.cbi.2022.110131] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 08/05/2022] [Accepted: 08/20/2022] [Indexed: 11/03/2022]
Abstract
Since cell membranes are complex systems, the use of model lipid bilayers is quite important for the study of their interactions with bioactive molecules. Mammalian cell membranes require cholesterol (CHOL) for their structure and function. For this reason, the mixtures of phospholipid and cholesterol are necessary to use in model membrane studies to better simulate the real systems. In the present study, we investigated the effect of the incorporation of hesperidin in model membranes consisting of dimyristoylphosphatidylcholine (DMPC) and CHOL by using differential scanning calorimetry (DSC), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and atomic force microscopy (AFM). ATR-FTIR results demonstrated that hesperidin increases the fluidity of the DMPC/CHOL binary system. DSC findings indicated that the presence of 5 mol% hesperidin induces a broadening of the main phase transition consisting of three overlapping components. AFM experiments showed that hesperidin increases the thickness of DMPC/CHOL lipid bilayer model membranes. In addition to experimental results, molecular docking studies were conducted with hesperidin and human lanosterol synthase (LS), which is an enzyme found in the final step of cholesterol synthesis, to characterize hesperidin's interactions with its surrounding via its hydroxyl and oxygen groups. Then, hesperidin's ADME/Tox (absorption, distribution, metabolism, excretion and toxicity) profile was computed to see the potential impact on living system. In conclusion, considering the data obtained from experimental studies, this work ensures molecular insights in the interaction between a flavonoid, as an antioxidant drug model, and lipids mimicking those found in mammalian membranes. Moreover, computational studies demonstrated that hesperidin may be a great potential for use as a therapeutic agent for hypercholesterolemia due to its antioxidant property.
Collapse
Affiliation(s)
- Cisem Altunayar-Unsalan
- Ege University Central Research Testing and Analysis Laboratory Research and Application Center, 35100, Bornova, Izmir, Turkey.
| | - Ozan Unsalan
- Ege University, Faculty of Science, Department of Physics, 35100, Bornova, Izmir, Turkey.
| | - Thomas Mavromoustakos
- Section of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, 15771, Greece.
| |
Collapse
|
17
|
Kabelka I, Georgiev V, Marx L, Pajtinka P, Lohner K, Pabst G, Dimova R, Vácha R. Magainin 2 and PGLa in bacterial membrane mimics III: Membrane fusion and disruption. Biophys J 2022; 121:852-861. [PMID: 35134334 PMCID: PMC8943694 DOI: 10.1016/j.bpj.2021.12.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 11/27/2021] [Accepted: 12/22/2021] [Indexed: 11/30/2022] Open
Abstract
We previously speculated that the synergistically enhanced antimicrobial activity of Magainin 2 and PGLa is related to membrane adhesion, fusion, and further membrane remodeling. Here we combined computer simulations with time-resolved in vitro fluorescence microscopy, cryoelectron microscopy, and small-angle X-ray scattering to interrogate such morphological and topological changes of vesicles at nanoscopic and microscopic length scales in real time. Coarse-grained simulations revealed formation of an elongated and bent fusion zone between vesicles in the presence of equimolar peptide mixtures. Vesicle adhesion and fusion were observed to occur within a few seconds by cryoelectron microscopy and corroborated by small-angle X-ray scattering measurements. The latter experiments indicated continued and time-extended structural remodeling for individual peptides or chemically linked peptide heterodimers but with different kinetics. Fluorescence microscopy further captured peptide-dependent adhesion, fusion, and occasional bursting of giant unilamellar vesicles a few seconds after peptide addition. The synergistic interactions between the peptides shorten the time response of vesicles and enhance membrane fusogenic and disruption properties of the equimolar mixture compared with the individual peptides.
Collapse
Affiliation(s)
- Ivo Kabelka
- CEITEC – Central European Institute of Technology, Masaryk University, Brno, Czech Republic,National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Vasil Georgiev
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, Potsdam, Germany
| | - Lisa Marx
- Institute of Molecular Biosciences, Biophysics Division, NAWI Graz, University of Graz, Graz, Austria,BioTechMed Graz, Graz, Austria
| | - Peter Pajtinka
- CEITEC – Central European Institute of Technology, Masaryk University, Brno, Czech Republic,National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic,Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Karl Lohner
- Institute of Molecular Biosciences, Biophysics Division, NAWI Graz, University of Graz, Graz, Austria,BioTechMed Graz, Graz, Austria
| | - Georg Pabst
- Institute of Molecular Biosciences, Biophysics Division, NAWI Graz, University of Graz, Graz, Austria,BioTechMed Graz, Graz, Austria
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, Potsdam, Germany
| | - Robert Vácha
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic; National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic; Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Brno, Czech Republic.
| |
Collapse
|
18
|
Novel nano spanlastic carrier system for buccal delivery of lacidipine. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2021.103061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
19
|
Karal MAS, Mokta NA, Levadny V, Belaya M, Ahmed M, Ahamed MK, Ahammed S. Effects of cholesterol on the size distribution and bending modulus of lipid vesicles. PLoS One 2022; 17:e0263119. [PMID: 35089965 PMCID: PMC8797199 DOI: 10.1371/journal.pone.0263119] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 01/12/2022] [Indexed: 11/19/2022] Open
Abstract
The influence of cholesterol fraction in the membranes of giant unilamellar vesicles (GUVs) on their size distributions and bending moduli has been investigated. The membranes of GUVs were synthesized by a mixture of two elements: electrically neutral lipid 1, 2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and cholesterol and also a mixture of three elements: electrically charged lipid 1,2-dioleoyl-sn-glycero-3-phospho-(1′-rac-glycerol) (DOPG), DOPC and cholesterol. The size distributions of GUVs have been presented by a set of histograms. The classical lognormal distribution is well fitted to the histograms, from where the average size of vesicle is obtained. The increase of cholesterol content in the membranes of GUVs increases the average size of vesicles in the population. Using the framework of Helmholtz free energy of the system, the theory developed by us is extended to explain the experimental results. The theory determines the influence of cholesterol on the bending modulus of membranes from the fitting of the proper histograms. The increase of cholesterol in GUVs increases both the average size of vesicles in population and the bending modulus of membranes.
Collapse
Affiliation(s)
- Mohammad Abu Sayem Karal
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
- * E-mail:
| | - Nadia Akter Mokta
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Victor Levadny
- Theoretical Problem Center of Physico-Chemical Pharmacology, Russian Academy of Sciences, Moscow, Russia
| | - Marina Belaya
- Department of Mathematics of Russian State University for the Humanities, Moscow, Russia
| | - 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
| | - Shareef Ahammed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| |
Collapse
|
20
|
Pritzl SD, Konrad DB, Ober MF, Richter AF, Frank JA, Nickel B, Trauner D, Lohmüller T. Optical Membrane Control with Red Light Enabled by Red-Shifted Photolipids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:385-393. [PMID: 34969246 DOI: 10.1021/acs.langmuir.1c02745] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Photoswitchable phospholipids, or "photolipids", that harbor an azobenzene group in their lipid tails are versatile tools to manipulate and control lipid bilayer properties with light. So far, the limited ultraviolet-A/blue spectral range in which the photoisomerization of regular azobenzene operates has been a major obstacle for biophysical or photopharmaceutical applications. Here, we report on the synthesis of nano- and micrometer-sized liposomes from tetra-ortho-chloro azobenzene-substituted phosphatidylcholine (termed red-azo-PC) that undergoes photoisomerization on irradiation with tissue-penetrating red light (≥630 nm). Photoswitching strongly affects the fluidity and mechanical properties of lipid membranes, although small-angle X-ray scattering and dynamic light scattering measurements reveal only a minor influence on the overall bilayer thickness and area expansion. By controlling the photostationary state and the photoswitching efficiency of red-azo-PC for specific wavelengths, we demonstrate that shape transitions such as budding or pearling and the division of cell-sized vesicles can be achieved. These results emphasize the applicability of red-azo-PC as a nanophotonic tool in synthetic biology and for biomedical applications.
Collapse
Affiliation(s)
- Stefanie D Pritzl
- Chair for Photonics and Optoelectronics, Nano-Institute Munich, Department of Physics, Ludwig-Maximilians-Universtität (LMU), Königinstraße 10, 80539 Munich, Germany
| | - David B Konrad
- Department of Pharmacy, Ludwig-Maximilians-Universtität (LMU), Butenandtstraße 5-13, 81377 Munich, Germany
| | - Martina F Ober
- Faculty of Physics and CeNS, Ludwig-Maximilians-Universtität (LMU), Geschwister-Scholl-Platz 1, 80539 München, Germany
| | - Alexander F Richter
- Chair for Photonics and Optoelectronics, Nano-Institute Munich, Department of Physics, Ludwig-Maximilians-Universtität (LMU), Königinstraße 10, 80539 Munich, Germany
| | - James A Frank
- Department of Chemical Physiology & Biochemistry, Vollum Institute, Oregon, Health & Science University, 3181 S.W. Sam Jackson Park Rd., Portland, Oregon 97239, United States
| | - Bert Nickel
- Faculty of Physics and CeNS, Ludwig-Maximilians-Universtität (LMU), Geschwister-Scholl-Platz 1, 80539 München, Germany
| | - Dirk Trauner
- Department of Chemistry, New York University, Silver Center, 100 Washington Square East, Room 712, New York, New York 10003, United States
| | - Theobald Lohmüller
- Chair for Photonics and Optoelectronics, Nano-Institute Munich, Department of Physics, Ludwig-Maximilians-Universtität (LMU), Königinstraße 10, 80539 Munich, Germany
| |
Collapse
|
21
|
Halder A, Karmakar S. An evidence of pores in phospholipid membrane induced by an antimicrobial peptide NK-2. Biophys Chem 2022; 282:106759. [PMID: 35008010 DOI: 10.1016/j.bpc.2022.106759] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/27/2021] [Accepted: 01/02/2022] [Indexed: 11/19/2022]
Abstract
NK-2, a peptide derived from a cationic core region of NK-lysin, has emerged as a promising candidate for new antibiotics. In contrast to classical antibiotics, antimicrobial peptides target bacterial membranes and disintegrate the membrane by forming the transmembrane pores. However, complete understanding of the precise mechanisms of cellular apoptosis and molecular basis of membrane selectivity is still in dispute. In the present study, we have shown that NK-2 forms trans-membrane pores on negatively charged phospholipid membranes using phase contrast microscopy. As bacteria mimicking membranes, we have chosen large unilamellar vesicles (LUV) and giant unilamellar vesicles (GUV) composed of negatively charged phospholipid, dioleoyl phosphatidyl glycerol (DOPG) and neutral phospholipid, dioleoyl phophatidylcholine (DOPC). Leakage of internal fluid of giant unilamellar vesicles (GUV), leading to decrease in intensity in the halo region of phase contrast micrographs, suggests the formation of transmembrane pores. No such reduction of intensity in the halo region of DOPC was observed, indicating, neutral vesicles does not exhibit pores. Rate constant reckoned from the decaying intensity in the halo region was found to be 0.007 s-1. Further, significant interaction of NK-2 with anionic membranes has been envisaged from zeta potential and dynamic light scattering. Binding free energy and other interaction parameters have been delineated using theoretical ansatz. A proliferation of average Size of anionic LUV on increasing NK-2 concentration indicates membrane-membrane interaction leading to peptide induced large aggregates of vesicles.
Collapse
Affiliation(s)
- Animesh Halder
- Soft matter and Biophysics Laboratory, Department of Physics, Jadavpur University, 188, Raja S. C. Mullick Road, Kolkata 700032, India
| | - Sanat Karmakar
- Soft matter and Biophysics Laboratory, Department of Physics, Jadavpur University, 188, Raja S. C. Mullick Road, Kolkata 700032, India.
| |
Collapse
|
22
|
Surface Properties of Synaptosomes in the Presence of L-Glutamic and Kainic Acids: In Vitro Alteration of the ATPase and Acetylcholinesterase Activities. MEMBRANES 2021; 11:membranes11120987. [PMID: 34940488 PMCID: PMC8708669 DOI: 10.3390/membranes11120987] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/12/2021] [Accepted: 12/14/2021] [Indexed: 11/23/2022]
Abstract
Morphologically and functionally identical to brain synapses, the nerve ending particles synaptosomes are biochemically derived membrane structures responsible for the transmission of neural information. Their surface and mechanical properties, measured in vitro, provide useful information about the functional activity of synapses in the brain in vivo. Glutamate and kainic acid are of particular interest because of their role in brain pathology (including causing seizure, migraine, ischemic stroke, aneurysmal subarachnoid hemorrhage, intracerebral hematoma, traumatic brain injury and stroke). The effects of the excitatory neurotransmitter L-glutamic acid and its agonist kainic acid are tested on Na+, K+-ATPase and Mg2+-ATPase activities in synaptic membranes prepared from the cerebral cortex of rat brain tissue. The surface parameters of synaptosome preparations from the cerebral cortex in the presence of L-glutamic and kainic acids are studied by microelectrophoresis for the first time. The studied neurotransmitters promote a significant increase in the electrophoretic mobility and surface electrical charge of synaptosomes at 1–4 h after isolation. The measured decrease in the bending modulus of model bimolecular membranes composed of monounsaturated lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine provides evidence for softer membranes in the presence of L-glutamate. Kainic acid does not affect membrane mechanical stability even at ten-fold higher concentrations. Both the L-glutamic and kainic acids reduce acetylcholinesterase activity and deviation from the normal functions of neurotransmission in synapses is presumed. The presented results regarding the modulation of the enzyme activity of synaptic membranes and surface properties of synaptosomes are expected by biochemical and biophysical studies to contribute to the elucidation of the molecular mechanisms of neurotransmitters/agonists’ action on membranes.
Collapse
|
23
|
Boban Z, Mardešić I, Subczynski WK, Raguz M. Giant Unilamellar Vesicle Electroformation: What to Use, What to Avoid, and How to Quantify the Results. MEMBRANES 2021; 11:membranes11110860. [PMID: 34832088 PMCID: PMC8622294 DOI: 10.3390/membranes11110860] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/03/2021] [Accepted: 11/05/2021] [Indexed: 12/12/2022]
Abstract
Since its inception more than thirty years ago, electroformation has become the most commonly used method for growing giant unilamellar vesicles (GUVs). Although the method seems quite straightforward at first, researchers must consider the interplay of a large number of parameters, different lipid compositions, and internal solutions in order to avoid artifactual results or reproducibility problems. These issues motivated us to write a short review of the most recent methodological developments and possible pitfalls. Additionally, since traditional manual analysis can lead to biased results, we have included a discussion on methods for automatic analysis of GUVs. Finally, we discuss possible improvements in the preparation of GUVs containing high cholesterol contents in order to avoid the formation of artifactual cholesterol crystals. We intend this review to be a reference for those trying to decide what parameters to use as well as an overview providing insight into problems not yet addressed or solved.
Collapse
Affiliation(s)
- Zvonimir Boban
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
- Doctoral Study of Biophysics, Faculty of Science, University of Split, 21000 Split, Croatia
| | - Ivan Mardešić
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
- Doctoral Study of Biophysics, Faculty of Science, University of Split, 21000 Split, Croatia
| | | | - Marija Raguz
- Department of Medical Physics and Biophysics, University of Split School of Medicine, 21000 Split, Croatia; (Z.B.); (I.M.)
- Correspondence: ; Tel.: +385-98-768-819
| |
Collapse
|
24
|
Almendro-Vedia V, Natale P, Valdivieso González D, Lillo MP, Aragones JL, López-Montero I. How rotating ATP synthases can modulate membrane structure. Arch Biochem Biophys 2021; 708:108939. [PMID: 34052190 DOI: 10.1016/j.abb.2021.108939] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 01/03/2023]
Abstract
F1Fo-ATP synthase (ATP synthase) is a central membrane protein that synthetizes most of the ATP in the cell through a rotational movement driven by a proton gradient across the hosting membrane. In mitochondria, ATP synthases can form dimers through specific interactions between some subunits of the protein. The dimeric form of ATP synthase provides the protein with a spontaneous curvature that sustain their arrangement at the rim of the high-curvature edges of mitochondrial membrane (cristae). Also, a direct interaction with cardiolipin, a lipid present in the inner mitochondrial membrane, induces the dimerization of ATP synthase molecules along cristae. The deletion of those biochemical interactions abolishes the protein dimerization producing an altered mitochondrial function and morphology. Mechanically, membrane bending is one of the key deformation modes by which mitochondrial membranes can be shaped. In particular, bending rigidity and spontaneous curvature are important physical factors for membrane remodelling. Here, we discuss a complementary mechanism whereby the rotatory movement of the ATP synthase might modify the mechanical properties of lipid bilayers and contribute to the formation and regulation of the membrane invaginations.
Collapse
Affiliation(s)
- Víctor Almendro-Vedia
- Departamento Química Física, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040, Madrid, Spain; Instituto de Investigación Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041, Madrid, Spain
| | - Paolo Natale
- Departamento Química Física, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040, Madrid, Spain; Instituto de Investigación Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041, Madrid, Spain
| | - David Valdivieso González
- Departamento Química Física, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040, Madrid, Spain; Instituto de Investigación Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041, Madrid, Spain
| | - M Pilar Lillo
- Departamento Química Física Biológica, Instituto de Química-Física "Rocasolano" (CSIC), Serrano 119, 28006, Madrid, Spain
| | - Juan L Aragones
- Departamento de Física Teórica de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Centre (IFIMAC), Universidad Autónoma de Madrid, E-28049, Madrid, Spain
| | - Iván López-Montero
- Departamento Química Física, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040, Madrid, Spain; Instituto de Investigación Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041, Madrid, Spain.
| |
Collapse
|
25
|
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
|
26
|
Van de Cauter L, Fanalista F, van Buren L, De Franceschi N, Godino E, Bouw S, Danelon C, Dekker C, Koenderink GH, Ganzinger KA. Optimized cDICE for Efficient Reconstitution of Biological Systems in Giant Unilamellar Vesicles. ACS Synth Biol 2021. [PMID: 34185516 DOI: 10.1101/2021.02.24.432456] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
Giant unilamellar vesicles (GUVs) are often used to mimic biological membranes in reconstitution experiments. They are also widely used in research on synthetic cells, as they provide a mechanically responsive reaction compartment that allows for controlled exchange of reactants with the environment. However, while many methods exist to encapsulate functional biomolecules in GUVs, there is no one-size-fits-all solution and reliable GUV fabrication still remains a major experimental hurdle in the field. Here, we show that defect-free GUVs containing complex biochemical systems can be generated by optimizing a double-emulsion method for GUV formation called continuous droplet interface crossing encapsulation (cDICE). By tightly controlling environmental conditions and tuning the lipid-in-oil dispersion, we show that it is possible to significantly improve the reproducibility of high-quality GUV formation as well as the encapsulation efficiency. We demonstrate efficient encapsulation for a range of biological systems including a minimal actin cytoskeleton, membrane-anchored DNA nanostructures, and a functional PURE (protein synthesis using recombinant elements) system. Our optimized cDICE method displays promising potential to become a standard method in biophysics and bottom-up synthetic biology.
Collapse
Affiliation(s)
| | - Federico Fanalista
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Lennard van Buren
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Nicola De Franceschi
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Elisa Godino
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Sharon Bouw
- Department of Living Matter, AMOLF, 1098 XG Amsterdam, The Netherlands
| | - Christophe Danelon
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Cees Dekker
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Gijsje H Koenderink
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | | |
Collapse
|
27
|
Van de Cauter L, Fanalista F, van Buren L, De Franceschi N, Godino E, Bouw S, Danelon C, Dekker C, Koenderink GH, Ganzinger KA. Optimized cDICE for Efficient Reconstitution of Biological Systems in Giant Unilamellar Vesicles. ACS Synth Biol 2021; 10:1690-1702. [PMID: 34185516 PMCID: PMC8291763 DOI: 10.1021/acssynbio.1c00068] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Indexed: 12/17/2022]
Abstract
Giant unilamellar vesicles (GUVs) are often used to mimic biological membranes in reconstitution experiments. They are also widely used in research on synthetic cells, as they provide a mechanically responsive reaction compartment that allows for controlled exchange of reactants with the environment. However, while many methods exist to encapsulate functional biomolecules in GUVs, there is no one-size-fits-all solution and reliable GUV fabrication still remains a major experimental hurdle in the field. Here, we show that defect-free GUVs containing complex biochemical systems can be generated by optimizing a double-emulsion method for GUV formation called continuous droplet interface crossing encapsulation (cDICE). By tightly controlling environmental conditions and tuning the lipid-in-oil dispersion, we show that it is possible to significantly improve the reproducibility of high-quality GUV formation as well as the encapsulation efficiency. We demonstrate efficient encapsulation for a range of biological systems including a minimal actin cytoskeleton, membrane-anchored DNA nanostructures, and a functional PURE (protein synthesis using recombinant elements) system. Our optimized cDICE method displays promising potential to become a standard method in biophysics and bottom-up synthetic biology.
Collapse
Affiliation(s)
| | - Federico Fanalista
- Department
of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Lennard van Buren
- Department
of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Nicola De Franceschi
- Department
of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Elisa Godino
- Department
of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Sharon Bouw
- Department
of Living Matter, AMOLF, 1098 XG Amsterdam, The Netherlands
| | - Christophe Danelon
- Department
of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Cees Dekker
- Department
of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Gijsje H. Koenderink
- Department
of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | | |
Collapse
|
28
|
Teiwes NK, Mey I, Baumann PC, Strieker L, Unkelbach U, Steinem C. Pore-Spanning Plasma Membranes Derived from Giant Plasma Membrane Vesicles. ACS APPLIED MATERIALS & INTERFACES 2021; 13:25805-25812. [PMID: 34043315 DOI: 10.1021/acsami.1c06404] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Giant plasma membrane vesicles (GPMVs) are a highly promising model system for the eukaryotic plasma membrane. The unresolved challenge, however, is a path to surface-based structures that allows accessibility to both sides of the plasma membrane through high-resolution techniques. Such an approach would pave the way to advanced chip-based technologies for the analysis of complex cell surfaces to study the roles of membrane proteins, host-pathogen interactions, and many other bioanalytical and sensing applications. This study reports the generation of planar supported plasma membranes and for the first-time pore-spanning plasma membranes (PSPMs) derived from pure GPMVs that are spread on activated solid and highly ordered porous silicon substrates. GPMVs were produced by two different vesiculation agents and were first investigated with respect to their growth behavior and phase separation. Second, these GPMVs were spread onto silicon substrates to form planar supported plasma membrane patches. PSPMs were obtained by spreading of pure GPMVs on oxygen-plasma activated porous substrates with pore diameters of 3.5 μm. Fluorescence micrographs unambiguously showed that the PSPMs partially phase separate in a mobile ordered phase surrounded by a disordered phase, which was supported by cholesterol extraction using methyl-β-cyclodextrin.
Collapse
Affiliation(s)
- Nikolas K Teiwes
- Georg-August Universität, Institut für Organische und Biomolekulare Chemie, Tammannstaße 2, 37077 Göttingen, Germany
| | - Ingo Mey
- Georg-August Universität, Institut für Organische und Biomolekulare Chemie, Tammannstaße 2, 37077 Göttingen, Germany
| | - Phila C Baumann
- Georg-August Universität, Institut für Organische und Biomolekulare Chemie, Tammannstaße 2, 37077 Göttingen, Germany
| | - Lena Strieker
- Georg-August Universität, Institut für Organische und Biomolekulare Chemie, Tammannstaße 2, 37077 Göttingen, Germany
| | - Ulla Unkelbach
- Georg-August Universität, Institut für Organische und Biomolekulare Chemie, Tammannstaße 2, 37077 Göttingen, Germany
| | - Claudia Steinem
- Georg-August Universität, Institut für Organische und Biomolekulare Chemie, Tammannstaße 2, 37077 Göttingen, Germany
- Max Planck Institute for Dynamics and Self-Organization, Am Fassberg 17, 37077 Göttingen, Germany
| |
Collapse
|
29
|
Fu M, Franquelim HG, Kretschmer S, Schwille P. Non‐Equilibrium Large‐Scale Membrane Transformations Driven by MinDE Biochemical Reaction Cycles. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202015184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Meifang Fu
- Dept. Cellular and Molecular Biophysics Max Planck Institute of Biochemistry Am Klopferspitz 18 82152 Martinsried Germany
| | - Henri G. Franquelim
- Dept. Cellular and Molecular Biophysics Max Planck Institute of Biochemistry Am Klopferspitz 18 82152 Martinsried Germany
| | - Simon Kretschmer
- Dept. Cellular and Molecular Biophysics Max Planck Institute of Biochemistry Am Klopferspitz 18 82152 Martinsried Germany
- Department of Bioengineering and Therapeutic Science University of California San Francisco San Francisco CA USA
| | - Petra Schwille
- Dept. Cellular and Molecular Biophysics Max Planck Institute of Biochemistry Am Klopferspitz 18 82152 Martinsried Germany
| |
Collapse
|
30
|
Fu M, Franquelim HG, Kretschmer S, Schwille P. Non-Equilibrium Large-Scale Membrane Transformations Driven by MinDE Biochemical Reaction Cycles. Angew Chem Int Ed Engl 2021; 60:6496-6502. [PMID: 33285025 PMCID: PMC7986748 DOI: 10.1002/anie.202015184] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Indexed: 12/11/2022]
Abstract
The MinDE proteins from E. coli have received great attention as a paradigmatic biological pattern-forming system. Recently, it has surfaced that these proteins do not only generate oscillating concentration gradients driven by ATP hydrolysis, but that they can reversibly deform giant vesicles. In order to explore the potential of Min proteins to actually perform mechanical work, we introduce a new model membrane system, flat vesicle stacks on top of a supported lipid bilayer. MinDE oscillations can repeatedly deform these flat vesicles into tubules and promote progressive membrane spreading through membrane adhesion. Dependent on membrane and buffer compositions, Min oscillations further induce robust bud formation. Altogether, we demonstrate that under specific conditions, MinDE self-organization can result in work performed on biomimetic systems and achieve a straightforward mechanochemical coupling between the MinDE biochemical reaction cycle and membrane transformation.
Collapse
Affiliation(s)
- Meifang Fu
- Dept. Cellular and Molecular BiophysicsMax Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
| | - Henri G. Franquelim
- Dept. Cellular and Molecular BiophysicsMax Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
| | - Simon Kretschmer
- Dept. Cellular and Molecular BiophysicsMax Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
- Department of Bioengineering and Therapeutic ScienceUniversity of California San FranciscoSan FranciscoCAUSA
| | - Petra Schwille
- Dept. Cellular and Molecular BiophysicsMax Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
| |
Collapse
|
31
|
Ma R, Berro J. Endocytosis against high turgor pressure is made easier by partial coating and freely rotating base. Biophys J 2021; 120:1625-1640. [PMID: 33675763 DOI: 10.1016/j.bpj.2021.02.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 01/27/2021] [Accepted: 02/11/2021] [Indexed: 02/02/2023] Open
Abstract
During clathrin-mediated endocytosis, a patch of flat plasma membrane is deformed into a vesicle. In walled cells, such as plants and fungi, the turgor pressure is high and pushes the membrane against the cell wall, thus hindering membrane internalization. In this work, we study how a patch of membrane is deformed against turgor pressure by force and by curvature-generating proteins. We show that a large amount of force is needed to merely start deforming the membrane and an even larger force is needed to pull a membrane tube. The magnitude of these forces strongly depends on how the base of the membrane is constrained and how the membrane is coated with curvature-generating proteins. In particular, these forces can be reduced by partially, but not fully, coating the membrane patch with curvature-generating proteins. Our theoretical results show excellent agreement with experimental data.
Collapse
Affiliation(s)
- Rui Ma
- Department of Physics, Xiamen University, Xiamen, China; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut; Nanobiology Institute, Yale University, West Haven, Connecticut.
| | - Julien Berro
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut; Nanobiology Institute, Yale University, West Haven, Connecticut; Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut.
| |
Collapse
|
32
|
Aden S, Snoj T, Anderluh G. The use of giant unilamellar vesicles to study functional properties of pore-forming toxins. Methods Enzymol 2021; 649:219-251. [PMID: 33712188 DOI: 10.1016/bs.mie.2021.01.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Pore-forming toxins (PFTs) act upon lipid membranes and appropriate model systems are of great importance in researching these proteins. Giant unilamellar vesicles (GUVs) are an excellent model membrane system to study interactions between lipids and proteins. Their main advantage is the size comparable to cells, which means that GUVs can be observed directly under the light microscope. Many PFTs properties can be studied by using GUVs, such as binding specificity, membrane reorganization upon protein binding and oligomerization, pore properties and mechanism of pore formation. GUVs also represent a good model for biotechnological approaches, e.g., in applications in synthetic biology and medicine. Each research area has its own demands for GUVs properties, so several different approaches for GUVs preparations have been developed and will be discussed in this chapter.
Collapse
Affiliation(s)
- Saša Aden
- Department for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Tina Snoj
- Department for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Gregor Anderluh
- Department for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia.
| |
Collapse
|
33
|
Ngassam VN, Su WC, Gettel DL, Deng Y, Yang Z, Wang-Tomic N, Sharma VP, Purushothaman S, Parikh AN. Recurrent dynamics of rupture transitions of giant lipid vesicles at solid surfaces. Biophys J 2021; 120:586-597. [PMID: 33460597 DOI: 10.1016/j.bpj.2021.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 11/20/2020] [Accepted: 01/07/2021] [Indexed: 10/22/2022] Open
Abstract
Single giant unilamellar vesicles (GUVs) rupture spontaneously from their salt-laden suspension onto solid surfaces. At hydrophobic surfaces, the GUVs rupture via a recurrent, bouncing ball rhythm. During each contact, the GUVs, rendered tense by the substrate interactions, porate, and spread a molecularly transformed motif of a monomolecular layer on the hydrophobic surface from the point of contact in a symmetric manner. The competition from pore closure, however, limits the spreading and produces a daughter vesicle, which re-engages with the substrate. At solid hydrophilic surfaces, by contrast, GUVs rupture via a distinctly different recurrent burst-heal dynamics; during burst, single pores nucleate at the contact boundary of the adhering vesicles, facilitating asymmetric spreading and producing a "heart"-shaped membrane patch. During the healing phase, the competing pore closure produces a daughter vesicle. In both cases, the pattern of burst-reseal events repeats multiple times, splashing and spreading the vesicular fragments as bilayer patches at the solid surface in a pulsatory manner. These remarkable recurrent dynamics arise, not because of the elastic properties of the solid surface, but because the competition between membrane spreading and pore healing, prompted by the surface-energy-dependent adhesion, determine the course of the topological transition.
Collapse
Affiliation(s)
- Viviane N Ngassam
- Department of Biomedical Engineering, University of California, Davis, California
| | - Wan-Chih Su
- Department of Chemistry, University of California, Davis, California
| | - Douglas L Gettel
- Department of Chemical Engineering, University of California, Davis, California
| | - Yawen Deng
- Department of Biomedical Engineering, University of California, Davis, California
| | - Zexu Yang
- Department of Biomedical Engineering, University of California, Davis, California
| | - Neven Wang-Tomic
- Department of Biomedical Engineering, University of California, Davis, California
| | - Varun P Sharma
- Department of Biomedical Engineering, University of California, Davis, California
| | - Sowmya Purushothaman
- Department of Biomedical Engineering, University of California, Davis, California
| | - Atul N Parikh
- Department of Biomedical Engineering, University of California, Davis, California; Department of Chemistry, University of California, Davis, California; Department of Chemical Engineering, University of California, Davis, California; Department of Materials Science and Engineering, University of California, Davis, California.
| |
Collapse
|
34
|
Diffusion on Membrane Domes, Tubes, and Pearling Structures. Biophys J 2020; 120:424-431. [PMID: 33359464 DOI: 10.1016/j.bpj.2020.12.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/19/2020] [Accepted: 12/08/2020] [Indexed: 02/06/2023] Open
Abstract
Diffusion is a fundamental mechanism for protein distribution in cell membranes. These membranes often exhibit complex shapes, which range from shallow domes to elongated tubular or pearl-like structures. Shape complexity of the membrane influences the diffusive spreading of proteins and molecules. Despite the importance membrane geometry plays in these diffusive processes, it is challenging to establish the dependence between diffusion and membrane morphology. We solve the diffusion equation numerically on various static curved shapes representative for experimentally observed membrane shapes. Our results show that membrane necks become diffusion barriers. We determine the diffusive half-time, i.e., the time that is required to reduce the amount of protein in the budded region by one half, and find a quadratic relation between the diffusive half-time and the averaged mean curvature of the membrane shape, which we rationalize by a scaling law. Our findings thus help estimate the characteristic diffusive timescale based on the simple measure of membrane mean curvature.
Collapse
|
35
|
Affiliation(s)
- Chandra Has
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| |
Collapse
|
36
|
Abstract
The endosomal sorting complexes required for transport (ESCRTs) I, -II and -III, and their associated factors are a collection of ∼20 proteins in yeast and ∼30 in mammals, responsible for severing membrane necks in processes that range from multivesicular body formation, HIV release and cytokinesis, to plasma and lysosomal membrane repair. ESCRTs are best known for 'reverse-topology' membrane scission, where they act on the inner surface of membrane necks, often when membranes are budded away from the cytosol. These events are driven by membrane-associated assemblies of dozens to hundreds of ESCRT molecules. ESCRT-III proteins form filaments with a variety of geometries and ESCRT-I has now been shown to also form helical structures. The complex nature of the system and the unusual topology of its action has made progress challenging, and led to controversies with regard to its underlying mechanism. This Review will focus on recent advances obtained by structural in vitro reconstitution and in silico mechanistic studies, and places them in their biological context. The field is converging towards a consensus on the broad outlines of a mechanism that is driven by a progressive ATP-dependent treadmilling exchange of ESCRT subunits, as well as compositional change and geometric transitions in ESCRT filaments.
Collapse
Affiliation(s)
- Mark Remec Pavlin
- Graduate Group in Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA.,California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
| | - James H Hurley
- Graduate Group in Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA .,California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA.,Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| |
Collapse
|
37
|
Martínez-Calvo A, Sevilla A. Universal Thinning of Liquid Filaments under Dominant Surface Forces. PHYSICAL REVIEW LETTERS 2020; 125:114502. [PMID: 32975989 DOI: 10.1103/physrevlett.125.114502] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
Theory and numerical simulations of the thinning of liquid threads at high superficial concentration of surfactants suggest the existence of an asymptotic regime where surface tension balances surface viscous stresses, leading to an exponential thinning with an e-fold time F(Θ)(3μ_{s}+κ_{s})/σ, where μ_{s} and κ_{s} are the surface shear and dilatational viscosity coefficients, σ is the interfacial tension, Θ=κ_{s}/μ_{s}, and F(Θ) is a universal function. The potential use of this phenomenon to measure the surface viscosity coefficients is discussed.
Collapse
Affiliation(s)
- A Martínez-Calvo
- Grupo de Mecánica de Fluidos, Departamento de Ingeniería Térmica y de Fluidos, Universidad Carlos III de Madrid. Avda. de la Universidad 30, 28911 Leganés, Madrid, Spain
| | - A Sevilla
- Grupo de Mecánica de Fluidos, Departamento de Ingeniería Térmica y de Fluidos, Universidad Carlos III de Madrid. Avda. de la Universidad 30, 28911 Leganés, Madrid, Spain
| |
Collapse
|
38
|
Membrane interactions in drug delivery: Model cell membranes and orthogonal techniques. Adv Colloid Interface Sci 2020; 281:102177. [PMID: 32417568 DOI: 10.1016/j.cis.2020.102177] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 03/05/2020] [Accepted: 05/07/2020] [Indexed: 01/22/2023]
Abstract
To generate the desired effect in the human body, the active pharmaceutical ingredient usually needs to interact with a receptor located on the cell membrane or inside the cell. Thus, understanding membrane interactions is of great importance when it comes to the development and testing of new drug molecules or new drug delivery systems. Nowadays, there is a tremendous selection of both model cell membranes and of techniques that can be used to characterize interactions between selected model cell membranes and a drug molecule, an excipient, or a drug delivery system. Having such a wide selection of model cell membranes and techniques available makes it sometimes challenging to select the optimal combination for a specific study. Furthermore, it is difficult to compare results obtained using different model cell membranes and techniques, and not all in vitro studies translate as well to an estimation of the in vivo biological activity or understanding of mode of action. This review provides an overview of the available lipid bilayer-based model cell membranes and of the most widely employed techniques for studying membrane interactions. Finally, the need for employing complimentary characterization techniques in order to acquire more reliable and in-depth information is highlighted.
Collapse
|
39
|
Wang L, Song S, van Hest J, Abdelmohsen LKEA, Huang X, Sánchez S. Biomimicry of Cellular Motility and Communication Based on Synthetic Soft-Architectures. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1907680. [PMID: 32250035 DOI: 10.1002/smll.201907680] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/13/2020] [Accepted: 02/24/2020] [Indexed: 06/11/2023]
Abstract
Cells, sophisticated membrane-bound units that contain the fundamental molecules of life, provide a precious library for inspiration and motivation for both society and academia. Scientists from various disciplines have made great endeavors toward the understanding of the cellular evolution by engineering artificial counterparts (protocells) that mimic or initiate structural or functional cellular aspects. In this regard, several works have discussed possible building blocks, designs, functions, or dynamics that can be applied to achieve this goal. Although great progress has been made, fundamental-yet complex-behaviors such as cellular communication, responsiveness to environmental cues, and motility remain a challenge, yet to be resolved. Herein, recent efforts toward utilizing soft systems for cellular mimicry are summarized-following the main outline of cellular evolution, from basic compartmentalization, and biological reactions for energy production, to motility and communicative behaviors between artificial cell communities or between artificial and natural cell communities. Finally, the current challenges and future perspectives in the field are discussed, hoping to inspire more future research and to help the further advancement of this field.
Collapse
Affiliation(s)
- Lei Wang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry & Chemical Engineering, Harbin Institute of Technology (HIT), Harbin, 150001, China
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 10-12, Barcelona, 08028, Spain
| | - Shidong Song
- Department of Biomedical Engineering & Department of Chemical Engineering and Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, Eindhoven, MB, 5600, The Netherlands
| | - Jan van Hest
- Department of Biomedical Engineering & Department of Chemical Engineering and Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, Eindhoven, MB, 5600, The Netherlands
| | - Loai K E A Abdelmohsen
- Department of Biomedical Engineering & Department of Chemical Engineering and Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, Eindhoven, MB, 5600, The Netherlands
| | - Xin Huang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry & Chemical Engineering, Harbin Institute of Technology (HIT), Harbin, 150001, China
| | - Samuel Sánchez
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 10-12, Barcelona, 08028, Spain
- Institucio Catalana de Recerca i Estudis Avancats (ICREA), Pg. Lluis Companys 23, Barcelona, 08010, Spain
| |
Collapse
|
40
|
The Neutrally Charged Diarylurea Compound PQ401 Kills Antibiotic-Resistant and Antibiotic-Tolerant Staphylococcus aureus. mBio 2020; 11:mBio.01140-20. [PMID: 32605985 PMCID: PMC7327171 DOI: 10.1128/mbio.01140-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Membrane-damaging antimicrobial agents have great potential to treat multidrug-resistant or multidrug-tolerant bacteria against which conventional antibiotics are not effective. However, their therapeutic applications are often hampered due to their low selectivity to bacterial over mammalian membranes or their potential for cross-resistance to a broad spectrum of cationic membrane-active antimicrobial agents. We discovered that the diarylurea derivative compound PQ401 has antimicrobial potency against multidrug-resistant and multidrug-tolerant Staphylococcus aureus. PQ401 selectively disrupts bacterial membrane lipid bilayers in comparison to mammalian membranes. Unlike cationic membrane-active antimicrobials, the neutral form of PQ401 rather than its cationic form exhibits maximum membrane activity. Overall, our results demonstrate that PQ401 could be a promising lead compound that overcomes the current limitations of membrane selectivity and cross-resistance. Also, this work provides deeper insight into the design and development of new noncharged membrane-targeting therapeutics to combat hard-to-cure bacterial infections. Resistance or tolerance to traditional antibiotics is a challenging issue in antimicrobial chemotherapy. Moreover, traditional bactericidal antibiotics kill only actively growing bacterial cells, whereas nongrowing metabolically inactive cells are tolerant to and therefore “persist” in the presence of legacy antibiotics. Here, we report that the diarylurea derivative PQ401, previously characterized as an inhibitor of the insulin-like growth factor I receptor, kills both antibiotic-resistant and nongrowing antibiotic-tolerant methicillin-resistant Staphylococcus aureus (MRSA) by lipid bilayer disruption. PQ401 showed several beneficial properties as an antimicrobial lead compound, including rapid killing kinetics, low probability for resistance development, high selectivity to bacterial membranes compared to mammalian membranes, and synergism with gentamicin. In contrast to well-studied membrane-disrupting cationic antimicrobial low-molecular-weight compounds and peptides, molecular dynamic simulations supported by efficacy data demonstrate that the neutral form of PQ401 penetrates and subsequently embeds into bacterial lipid bilayers more effectively than the cationic form. Lastly, PQ401 showed efficacy in both the Caenorhabditis elegans and Galleria mellonella models of MRSA infection. These data suggest that PQ401 may be a lead candidate for repurposing as a membrane-active antimicrobial and has potential for further development as a human antibacterial therapeutic for difficult-to-treat infections caused by both drug-resistant and -tolerant S. aureus.
Collapse
|
41
|
Chen P, Xu Z, Zhu G, Dai X, Yan LT. Cellular Uptake of Active Particles. PHYSICAL REVIEW LETTERS 2020; 124:198102. [PMID: 32469587 DOI: 10.1103/physrevlett.124.198102] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/23/2020] [Indexed: 05/20/2023]
Abstract
Active particles are widely recognized to potentially revolutionize technologies in numerous biomedical applications. However, the physical origin behind cellular uptake of these particles in the nonequilibrium state remains scarcely understood. Here we combine Brownian dynamics simulation as well as theoretical analysis to provide the criterion for cellular uptake of active particles, related to various physical attributes. Upon enhancing the activity, the uptake efficiency for the active particles with tilted orientation is examined to be nonmonotonic, in stark contrast to the monotonic dependence for active particles orientated normally to the membrane. This can be attributed to the interplay between membrane adhesion energy and kinetic energy of active particles, resulting in unique kinetic pathways. Furthermore, a theoretical model that captures the essential physics of the cellular endocytosis process is developed to reproduce this nonmonotonic feature. The results are of immediate interest to understand and tune activity-mediated cellular interaction and internalization of such emerging colloids.
Collapse
Affiliation(s)
- Pengyu Chen
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Ziyang Xu
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Guolong Zhu
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Xiaobin Dai
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Li-Tang Yan
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| |
Collapse
|
42
|
Roy D, Steinkühler J, Zhao Z, Lipowsky R, Dimova R. Mechanical Tension of Biomembranes Can Be Measured by Super Resolution (STED) Microscopy of Force-Induced Nanotubes. NANO LETTERS 2020; 20:3185-3191. [PMID: 32320255 PMCID: PMC7304919 DOI: 10.1021/acs.nanolett.9b05232] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/20/2020] [Indexed: 05/26/2023]
Abstract
Membrane tension modulates the morphology of plasma-membrane tubular protrusions in cells but is difficult to measure. Here, we propose to use microscopy imaging to assess the membrane tension. We report direct measurement of membrane nanotube diameters with unprecedented resolution using stimulated emission depletion (STED) microscopy. For this purpose, we integrated an optical tweezers setup in a commercial microscope equipped for STED imaging and established micropipette aspiration of giant vesicles. Membrane nanotubes were pulled from the vesicles at specific membrane tension imposed by the aspiration pipet. Tube diameters calculated from the applied tension using the membrane curvature elasticity model are in excellent agreement with data measured directly with STED. Our approach can be extended to cellular membranes and will then allow us to estimate the mechanical membrane tension within the force-induced nanotubes.
Collapse
|
43
|
Priti Sinha K, Das S, Karyappa RB, Thaokar RM. Electrohydrodynamics of Vesicles and Capsules. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:4863-4886. [PMID: 32275824 DOI: 10.1021/acs.langmuir.9b03971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Giant unilamellar vesicles (GUVs) made up of phospholipid bilayer membranes (liposomes) and elastic capsules with a cross-linked, polymerized membrane, have emerged as biomimetic alternatives to investigating biological cells such as leukocytes and erythrocytes. This feature article looks at the similarities and differences in the electrohydrodynamics (EHD) of vesicles and capsules under electric fields that determines their electromechanical response. The physics of EHD is illustrated through several examples such as the electrodeformation of single and compound, spherical and cylindrical, and charged and uncharged vesicles in uniform and nonuniform electric fields, and the relevance and challenges are discussed. Both small and large deformation results are discussed. The use of EHD in understanding complex interfacial kinetics in capsules and the synthesis of nonspherical capsules using electric fields are also presented. Finally, the review looks at the large electrodeformation of water-in-water capsules and the relevance of constitutive laws in their response.
Collapse
Affiliation(s)
- Kumari Priti Sinha
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Sudip Das
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Rahul Bapusaheb Karyappa
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Rochish M Thaokar
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| |
Collapse
|
44
|
Wongsirojkul N, Shimokawa N, Opaprakasit P, Takagi M, Hamada T. Osmotic-Tension-Induced Membrane Lateral Organization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:2937-2945. [PMID: 32175748 DOI: 10.1021/acs.langmuir.9b03893] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Alteration of lipid raft organization manifesting as phase separation is important for cellular processes, such as signaling and trafficking. Such behaviors and dynamics of lipid membranes can be affected by external stimuli including both physical and chemical stimuli. In this study, we focused on osmotic-tension-induced phase separation. The effects of osmotic tension on the phase behaviors of vesicles consisting of dioleoylphosphocholine (DOPC)/dipalmitoylphosphocholine (DPPC)/cholesterol (Chol) were quantitatively studied at different temperatures by fluorescence microscopy. We determined the ternary phase diagrams and found that tension leads to a shift in the miscibility temperature. Cholesterol plays a key role in determining the extent of this shift. In addition, we found that osmotic tension can enhance the line tension. The physicochemical mechanism of osmotic-pressure-induced phase separation is discussed.
Collapse
Affiliation(s)
- Nichaporn Wongsirojkul
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi City, Ishikawa 923-1292, Japan
- School of Biochemical Engineering and Technology, Sirindhorn International Institute of Technology (SIIT), Thammasat University, Khlong Luang, Pathum Thani 12121, Thailand
| | - Naofumi Shimokawa
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi City, Ishikawa 923-1292, Japan
| | - Pakorn Opaprakasit
- School of Biochemical Engineering and Technology, Sirindhorn International Institute of Technology (SIIT), Thammasat University, Khlong Luang, Pathum Thani 12121, Thailand
| | - Masahiro Takagi
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi City, Ishikawa 923-1292, Japan
| | - Tsutomu Hamada
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi City, Ishikawa 923-1292, Japan
| |
Collapse
|
45
|
Ambruş VE, Busuioc S, Wagner AJ, Paillusson F, Kusumaatmaja H. Multicomponent flow on curved surfaces: A vielbein lattice Boltzmann approach. Phys Rev E 2019; 100:063306. [PMID: 31962535 DOI: 10.1103/physreve.100.063306] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Indexed: 11/07/2022]
Abstract
We develop and implement a finite difference lattice Boltzmann scheme to study multicomponent flows on curved surfaces, coupling the continuity and Navier-Stokes equations with the Cahn-Hilliard equation to track the evolution of the binary fluid interfaces. The standard lattice Boltzmann method relies on regular Cartesian grids, which makes it generally unsuitable to study flow problems on curved surfaces. To alleviate this limitation, we use a vielbein formalism to write the Boltzmann equation on an arbitrary geometry, and solve the evolution of the fluid distribution functions using a finite difference method. Focusing on the torus geometry as an example of a curved surface, we demonstrate drift motions of fluid droplets and stripes embedded on the surface of the torus. Interestingly, they migrate in opposite directions: fluid droplets to the outer side while fluid stripes to the inner side of the torus. For the latter we demonstrate that the global minimum configuration is unique for small stripe widths, but it becomes bistable for large stripe widths. Our simulations are also in agreement with analytical predictions for the Laplace pressure of the fluid stripes, and their damped oscillatory motion as they approach equilibrium configurations, capturing the corresponding decay timescale and oscillation frequency. Finally, we simulate the coarsening dynamics of phase separating binary fluids in the hydrodynamics and diffusive regimes for tori of various shapes, and compare the results against those for a flat two-dimensional surface. Our finite difference lattice Boltzmann scheme can be extended to other surfaces and coupled to other dynamical equations, opening up a vast range of applications involving complex flows on curved geometries.
Collapse
Affiliation(s)
- Victor E Ambruş
- Department of Physics, West University of Timişoara, 300223 Timişoara, Romania
| | - Sergiu Busuioc
- Department of Physics, West University of Timişoara, 300223 Timişoara, Romania
| | - Alexander J Wagner
- Department of Physics, North Dakota State University, Fargo, North Dakota 58108, USA
| | - Fabien Paillusson
- School of Mathematics and Physics, University of Lincoln, Lincoln LN6 7TS, United Kingdom
| | - Halim Kusumaatmaja
- Department of Physics, Durham University, Durham, DH1 3LE, United Kingdom
| |
Collapse
|
46
|
Piontek MC, Lira RB, Roos WH. Active probing of the mechanical properties of biological and synthetic vesicles. Biochim Biophys Acta Gen Subj 2019; 1865:129486. [PMID: 31734458 DOI: 10.1016/j.bbagen.2019.129486] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 11/05/2019] [Accepted: 11/09/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND The interest in mechanics of synthetic and biological vesicles has been continuously growing during the last decades. Liposomes serve as model systems for investigating fundamental membrane processes and properties. More recently, extracellular vesicles (EVs) have been investigated mechanically as well. EVs are widely studied in fundamental and applied sciences, but their material properties remained elusive until recently. Elucidating the mechanical properties of vesicles is essential to unveil the mechanisms behind a variety of biological processes, e.g. budding, vesiculation and cellular uptake mechanisms. SCOPE OF REVIEW The importance of mechanobiology for studies of vesicles and membranes is discussed, as well as the different available techniques to probe their mechanical properties. In particular, the mechanics of vesicles and membranes as obtained by nanoindentation, micropipette aspiration, optical tweezers, electrodeformation and electroporation experiments is addressed. MAJOR CONCLUSIONS EVs and liposomes possess an astonishing rich, diverse behavior. To better understand their properties, and for optimization of their applications in nanotechnology, an improved understanding of their mechanical properties is needed. Depending on the size of the vesicles and the specific scientific question, different techniques can be chosen for their mechanical characterization. GENERAL SIGNIFICANCE Understanding the mechanical properties of vesicles is necessary to gain deeper insight in the fundamental biological mechanisms involved in vesicle generation and cellular uptake. This furthermore facilitates technological applications such as using vesicles as targeted drug delivery vehicles. Liposome studies provide insight into fundamental membrane processes and properties, whereas the role and functioning of EVs in biology and medicine are increasingly elucidated.
Collapse
Affiliation(s)
- Melissa C Piontek
- Moleculaire Biofysica, Zernike Instituut, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands.
| | - Rafael B Lira
- Moleculaire Biofysica, Zernike Instituut, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands.
| | - Wouter H Roos
- Moleculaire Biofysica, Zernike Instituut, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands.
| |
Collapse
|
47
|
Moga A, Yandrapalli N, Dimova R, Robinson T. Optimization of the Inverted Emulsion Method for High-Yield Production of Biomimetic Giant Unilamellar Vesicles. Chembiochem 2019; 20:2674-2682. [PMID: 31529570 PMCID: PMC6856842 DOI: 10.1002/cbic.201900529] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Indexed: 01/21/2023]
Abstract
In the field of bottom-up synthetic biology, lipid vesicles provide an important role in the construction of artificial cells. Giant unilamellar vesicles (GUVs), due to their membrane's similarity to natural biomembranes, have been widely used as cellular mimics. So far, several methods exist for the production of GUVs with the possibility to encapsulate biological macromolecules. The inverted emulsion-based method is one such technique, which has great potential for rapid production of GUVs with high encapsulation efficiencies for large biomolecules. However, the lack of understanding of various parameters that affect production yields has resulted in sparse adaptation within the membrane and bottom-up synthetic biology research communities. Here, we optimize various parameters of the inverted emulsion-based method to maximize the production of GUVs. We demonstrate that the density difference between the emulsion droplets, oil phase, and the outer aqueous phase plays a crucial role in vesicle formation. We also investigated the impact that centrifugation speed/time, lipid concentration, pH, temperature, and emulsion droplet volume has on vesicle yield and size. Compared to conventional electroformation, our preparation method was not found to significantly alter the membrane mechanical properties. Finally, we optimize the parameters to minimize the time from workbench to microscope and in this way open up the possibility of time-sensitive experiments. In conclusion, our findings will promote the usage of the inverted emulsion method for basic membrane biophysics studies as well as the development of GUVs for use as future artificial cells.
Collapse
Affiliation(s)
- Akanksha Moga
- Theory & Bio-Systems DepartmentMax Planck Institute of Colloids and InterfacesPotsdam-Golm Science Park14424PotsdamGermany
| | - Naresh Yandrapalli
- Theory & Bio-Systems DepartmentMax Planck Institute of Colloids and InterfacesPotsdam-Golm Science Park14424PotsdamGermany
| | - Rumiana Dimova
- Theory & Bio-Systems DepartmentMax Planck Institute of Colloids and InterfacesPotsdam-Golm Science Park14424PotsdamGermany
| | - Tom Robinson
- Theory & Bio-Systems DepartmentMax Planck Institute of Colloids and InterfacesPotsdam-Golm Science Park14424PotsdamGermany
| |
Collapse
|
48
|
Steinkühler J, Sezgin E, Urbančič I, Eggeling C, Dimova R. Mechanical properties of plasma membrane vesicles correlate with lipid order, viscosity and cell density. Commun Biol 2019; 2:337. [PMID: 31531398 PMCID: PMC6744421 DOI: 10.1038/s42003-019-0583-3] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 08/15/2019] [Indexed: 11/08/2022] Open
Abstract
Regulation of plasma membrane curvature and composition governs essential cellular processes. The material property of bending rigidity describes the energetic cost of membrane deformations and depends on the plasma membrane molecular composition. Because of compositional fluctuations and active processes, it is challenging to measure it in intact cells. Here, we study the plasma membrane using giant plasma membrane vesicles (GPMVs), which largely preserve the plasma membrane lipidome and proteome. We show that the bending rigidity of plasma membranes under varied conditions is correlated to readout from environment-sensitive dyes, which are indicative of membrane order and microviscosity. This correlation holds across different cell lines, upon cholesterol depletion or enrichment of the plasma membrane, and variations in cell density. Thus, polarity- and viscosity-sensitive probes represent a promising indicator of membrane mechanical properties. Additionally, our results allow for identifying synthetic membranes with a few well defined lipids as optimal plasma membrane mimetics.
Collapse
Affiliation(s)
- Jan Steinkühler
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Erdinc Sezgin
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
| | - Iztok Urbančič
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
- Condensed Matter Physics Department, “Jožef Stefan” Institute, Ljubljana, Slovenia
| | - Christian Eggeling
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, Oxford, OX3 9DS UK
- Institute of Applied Optics Friedrich‐Schiller‐University Jena, Max-Wien Platz 4, 07743 Jena, Germany
- Leibniz Institute of Photonic Technology e.V., Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Rumiana Dimova
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| |
Collapse
|
49
|
Miettinen MS, Lipowsky R. Bilayer Membranes with Frequent Flip-Flops Have Tensionless Leaflets. NANO LETTERS 2019; 19:5011-5016. [PMID: 31056917 PMCID: PMC6750870 DOI: 10.1021/acs.nanolett.9b01239] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/03/2019] [Indexed: 05/28/2023]
Abstract
Biomembranes are built up from lipid bilayers with two leaflets that typically differ in their lipid composition. Each lipid molecule stays within one leaflet of the bilayer before it undergoes a transition, or flip-flop, to the other leaflet. The corresponding flip-flop times are very different for different lipid species and vary over several orders of magnitude. Here, we use molecular dynamics simulations to elucidate the consequences of this separation of time scales for compositionally asymmetric bilayers. We first study bilayers with two lipid components that do not undergo flip-flops on the accessible time scales. In such a situation, one must distinguish a bilayer state in which both leaflets have the same preferred area from another state in which each leaflet is tensionless. However, when we add a third lipid component that undergoes frequent flip-flops, the bilayer relaxes toward the state with tensionless leaflets, not to the state with equal preferred leaflet areas. Furthermore, we show that bilayers with compositional asymmetry acquire a significant spontaneous curvature even if both leaflets are tensionless. Our results can be extended to lipid bilayers with a large number of lipid components provided at least one of these components undergoes frequent flip-flops. For cellular membranes containing lipid pumps, the leaflet tensions also depend on the rates of protein-induced flip-flops.
Collapse
|
50
|
Influenza A matrix protein M1 induces lipid membrane deformation via protein multimerization. Biosci Rep 2019; 39:BSR20191024. [PMID: 31324731 PMCID: PMC6682550 DOI: 10.1042/bsr20191024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 07/09/2019] [Accepted: 07/18/2019] [Indexed: 12/16/2022] Open
Abstract
The matrix protein M1 of the Influenza A virus (IAV) is supposed to mediate viral assembly and budding at the plasma membrane (PM) of infected cells. In order for a new viral particle to form, the PM lipid bilayer has to bend into a vesicle toward the extracellular side. Studies in cellular models have proposed that different viral proteins might be responsible for inducing membrane curvature in this context (including M1), but a clear consensus has not been reached. In the present study, we use a combination of fluorescence microscopy, cryogenic transmission electron microscopy (cryo-TEM), cryo-electron tomography (cryo-ET) and scanning fluorescence correlation spectroscopy (sFCS) to investigate M1-induced membrane deformation in biophysical models of the PM. Our results indicate that M1 is indeed able to cause membrane curvature in lipid bilayers containing negatively charged lipids, in the absence of other viral components. Furthermore, we prove that protein binding is not sufficient to induce membrane restructuring. Rather, it appears that stable M1-M1 interactions and multimer formation are required in order to alter the bilayer three-dimensional structure, through the formation of a protein scaffold. Finally, our results suggest that, in a physiological context, M1-induced membrane deformation might be modulated by the initial bilayer curvature and the lateral organization of membrane components (i.e. the presence of lipid domains).
Collapse
|