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Pabst G, Keller S. Exploring membrane asymmetry and its effects on membrane proteins. Trends Biochem Sci 2024; 49:333-345. [PMID: 38355393 DOI: 10.1016/j.tibs.2024.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/08/2024] [Accepted: 01/19/2024] [Indexed: 02/16/2024]
Abstract
Plasma membranes utilize free energy to maintain highly asymmetric, non-equilibrium distributions of lipids and proteins between their two leaflets. In this review we discuss recent progress in quantitative research enabled by using compositionally controlled asymmetric model membranes. Both experimental and computational studies have shed light on the nuanced mechanisms that govern the structural and dynamic coupling between compositionally distinct bilayer leaflets. This coupling can increase the membrane bending rigidity and induce order - or lipid domains - across the membrane. Furthermore, emerging evidence indicates that integral membrane proteins not only respond to asymmetric lipid distributions but also exhibit intriguing asymmetric properties themselves. We propose strategies to advance experimental research, aiming for a deeper, quantitative understanding of membrane asymmetry, which carries profound implications for cellular physiology.
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Affiliation(s)
- Georg Pabst
- Biophysics, Institute of Molecular Bioscience (IMB), NAWI Graz, University of Graz, Graz 8010, Austria; BioTechMed-Graz, Graz, Austria; Field of Excellence BioHealth, University of Graz, Graz, Austria.
| | - Sandro Keller
- Biophysics, Institute of Molecular Bioscience (IMB), NAWI Graz, University of Graz, Graz 8010, Austria; BioTechMed-Graz, Graz, Austria; Field of Excellence BioHealth, University of Graz, Graz, Austria
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2
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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.
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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
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Hiroshima Y, Kido JI, Kido R, Yoshida K, Bando M, Kajimoto K, Yumoto H, Shinohara Y. β-defensin 2 synthesized by a cell-free protein synthesis system and encapsulated in liposomes inhibits adhesion of Porphyromonas gingivalis to oral epithelial cells. Odontology 2023; 111:830-838. [PMID: 36745267 DOI: 10.1007/s10266-023-00789-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 01/29/2023] [Indexed: 02/07/2023]
Abstract
β-defensin 2 (BD-2), an antimicrobial peptide (AMP), is expressed by oral epithelial cells and plays an important role in innate immunity of the oral cavity. Cell-free protein synthesis (CFPS) systems have been studied for the synthesis of various proteins, however, the synthesis of BD-2 by a CFPS system has not been extensively explored. Liposomes have been developed as tools for drug delivery. A delivery of liposome-encapsulated AMP to oral epithelium may be useful to prevent oral infectious diseases. In the present study, we investigated the antimicrobial activity of the BD-2 protein, artificially synthesized using a CFPS system and encapsulated in liposomes. BD-2 protein was artificially synthesized using template DNA and a reconstituted CFPS system and was identified by western blotting. Bilayer liposomes were prepared using 1,2-dioleoyl-sn-glycero-3-phospho-choline and 3-sn-phosphatidylcholine from egg yolk. The artificially synthesized BD-2 was encapsulated in liposomes, collected by ultrafiltration, and detected by western blotting. Human oral epithelial cells were cultured with the liposome-encapsulated BD-2 and the concentration of BD-2 in the cell lysate of the culture with the synthesized BD-2 was higher than that of the control cultures. The antimicrobial activity of the synthesized BD-2 was investigated by an adhesion assay of Porphyromonas gingivalis to oral epithelial cells. The artificially synthesized BD-2 and its liposome significantly inhibited adhesion of P. gingivalis to oral epithelial cells. These results suggest that artificially synthesized BD-2 and liposome-encapsulated BD-2 show antimicrobial activity and can potentially play a role in oral healthcare for periodontal diseases.
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Affiliation(s)
- Yuka Hiroshima
- Department of Oral Microbiology, Tokushima University, 3-18-15, Kuramoto, Tokushima, 770-8504, Japan.
| | - Jun-Ichi Kido
- Department of Periodontology and Endodontology, Tokushima University, Tokushima, Japan
| | - Rie Kido
- Department of Periodontology and Endodontology, Tokushima University, Tokushima, Japan
| | - Kaya Yoshida
- Department of Oral Healthcare Education, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Mika Bando
- Department of Periodontology and Endodontology, Tokushima University, Tokushima, Japan
| | - Kazuaki Kajimoto
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology, Tokyo, Japan
| | - Hiromichi Yumoto
- Department of Periodontology and Endodontology, Tokushima University, Tokushima, Japan
| | - Yasuo Shinohara
- Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
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4
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Kido JI, Hiroshima Y, Kido R, Yoshida K, Inagaki Y, Naruishi K, Kajimoto K, Kataoka M, Shinohara Y, Yumoto H. Lipocalin 2, synthesized using a cell-free protein synthesis system and encapsulated into liposomes, inhibits the adhesion of Porphyromonas gingivalis to human oral epithelial cells. J Periodontal Res 2023; 58:262-273. [PMID: 36579753 DOI: 10.1111/jre.13088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 12/08/2022] [Accepted: 12/13/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND OBJECTIVE Lipocalin 2 (LCN2), a glycoprotein expressed in epithelial cells and leukocytes, has an antibacterial effect and plays a role in innate immunity. The delivery of LCN2 encapsulated in liposomes to oral epithelium may be useful to prevent oral infectious diseases. This study aimed to investigate the inhibitory effect of LCN2, artificially synthesized using a cell-free protein synthesis (CFPS) system, on the adhesion of Porphyromonas gingivalis to oral epithelial cells in order to approach oral healthcare using LCN2. METHODS LCN 2 was synthesized using a CFPS system and assayed by Western blotting, mass spectrometry and enzyme-linked immunosorbent assay (ELISA). The bilayer liposomes were prepared by the spontaneous transfer method using 1,2-dioleoyl-sn-glycero-3 phosphocholine (DOPC), 3-sn-phosphatidylcholine from Egg Yolk (Egg-PC), and 1,2-dioleoyl-sn-glycero-3 phosphoethanolamine (DOPE). The cellular and medium fractions derived from the culture of oral epithelial cells with liposome-encapsulated LCN2 were assayed by Western blotting and ELISA. The effect of the synthesized LCN2 on adhesion of the labeled P. gingivalis to oral epithelial cells was investigated as an evaluation of its antibacterial activity. RESULTS The synthesized LCN2 protein was identified by Western blotting; its amino acid sequence was similar to that of recombinant LCN2 protein. The additions of DOPE and octa-arginine in the outer lipid-layer components of liposome significantly increased the delivery of liposomes to epithelial cells. When oral epithelial cells were cultured with the synthesized and liposome-encapsulated LCN2, LCN2 was identified in the cellular and medium fractions by Western blotting and its concentration in the cellular fraction from the culture with the synthesized LCN2 was significantly higher than that of a template DNA-free protein. The synthesized LCN2 and liposome-encapsulated LCN2 significantly inhibited the adhesion of P. gingivalis to oral epithelial cells compared with template DNA-free protein. CONCLUSION LCN2 was artificially synthesized by a CFPS system, encapsulated in liposomes, and delivered to oral epithelial cells, and demonstrated an antibacterial action against P. gingivalis. This approach may become a useful model for oral healthcare.
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Affiliation(s)
- Jun-Ichi Kido
- Department of Periodontology and Endodontology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Yuka Hiroshima
- Department of Oral Microbiology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Rie Kido
- Department of Periodontology and Endodontology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Kaya Yoshida
- Department of Oral Healthcare Education, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Yuji Inagaki
- Department of Periodontology and Endodontology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Koji Naruishi
- Department of Periodontology and Endodontology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Kazuaki Kajimoto
- Health and Medical Research Institute, National Institute of Advanced Industrial, Science and Technology, Tokushima, Japan
| | - Masatoshi Kataoka
- Health and Medical Research Institute, National Institute of Advanced Industrial, Science and Technology, Tokushima, Japan
| | - Yasuo Shinohara
- Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Hiromichi Yumoto
- Department of Periodontology and Endodontology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
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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.
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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
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6
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Yoda T. Charged Lipids Influence Phase Separation in Cell-Sized Liposomes Containing Cholesterol or Ergosterol. MEMBRANES 2022; 12:membranes12111121. [PMID: 36363676 PMCID: PMC9697951 DOI: 10.3390/membranes12111121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/06/2022] [Accepted: 11/07/2022] [Indexed: 05/14/2023]
Abstract
Positively charged ion species and charged lipids play specific roles in biochemical processes, especially those involving cell membranes. The cell membrane and phase separation domains are attractive research targets to study signal transduction. The phase separation structure and functions of cell-sized liposomes containing charged lipids and cholesterol have been investigated earlier, and the domain structure has also been studied in a membrane model, containing the yeast sterol ergosterol. The present study investigates phase-separated domain structure alterations in membranes containing charged lipids when cholesterol is substituted with ergosterol. This study finds that ergosterol increases the homogeneity of membranes containing charged lipids. Cholesterol-containing membranes are more sensitive to a charged state, and ergosterol-containing liposomes show lower responses to charged lipids. These findings may improve our understanding of the differences in both yeast and mammalian cells, as well as the interactions of proteins with lipids during signal transduction.
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Affiliation(s)
- Tsuyoshi Yoda
- Hachinohe Industrial Research Institute, Aomori Prefectural Industrial Technology Research Center, 1-4-43 Kita-inter-kogyodanchi, Hachinohe City 039-2245, Aomori, Japan; ; Tel.: +81-178-21-2100
- The United Graduate School of Agricultural Sciences, Iwate University, 3-18-8 Ueda, Morioka City 020-8550, Iwate, Japan
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7
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Varma M, Deserno M. Distribution of cholesterol in asymmetric membranes driven by composition and differential stress. Biophys J 2022; 121:4001-4018. [PMID: 35927954 PMCID: PMC9674969 DOI: 10.1016/j.bpj.2022.07.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 07/11/2022] [Accepted: 07/27/2022] [Indexed: 11/25/2022] Open
Abstract
Many lipid membranes of eukaryotic cells are asymmetric, which means the two leaflets differ in at least one physical property, such as lipid composition or lateral stress. Maintaining this asymmetry is helped by the fact that ordinary phospholipids rarely transition between leaflets, but cholesterol is an exception: its flip-flop times are in the microsecond range, so that its distribution between leaflets is determined by a chemical equilibrium. In particular, preferential partitioning can draw cholesterol into a more saturated leaflet, and phospholipid number asymmetry can force it out of a compressed leaflet. Combining highly coarse-grained membrane simulations with theoretical modeling, we investigate how these two driving forces play against each other until cholesterol's chemical potential is equilibrated. The theory includes two coupled elastic sheets and a Flory-Huggins mixing free energy with a χ parameter. We obtain a relationship between χ and the interaction strength between cholesterol and lipids in either of the two leaflets, and we find that it depends, albeit weakly, on lipid number asymmetry. The differential stress measurements under various asymmetry conditions agree with our theoretical predictions. Using the two kinds of asymmetries in combination, we find that it is possible to counteract the phospholipid number bias, and the resultant stress in the membrane, via the control of cholesterol mixing in the leaflets.
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Affiliation(s)
- Malavika Varma
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Markus Deserno
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania.
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8
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Stano P. Commentary: Rapid and facile preparation of giant vesicles by the droplet transfer method for artificial cell construction. Front Bioeng Biotechnol 2022; 10:1037809. [PMID: 36312559 PMCID: PMC9614326 DOI: 10.3389/fbioe.2022.1037809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 09/26/2022] [Indexed: 11/15/2022] Open
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9
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Yoda T. Phase Separation in Liposomes Determined by Ergosterol and Classified Using Machine Learning. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2022; 28:1-8. [PMID: 36117262 DOI: 10.1017/s1431927622012521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Recent studies indicated that ergosterol (Erg) helps form strongly ordered lipid domains in membranes that depend on their chemical characters. However, direct evidence of concentration-dependent interaction of Erg with lipid membranes has not been reported. We studied the Erg concentration-dependent changes in the phase behaviors of membranes using cell-sized liposomes containing 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC)/1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). We observed the concentration range of phase separation in ternary membranes was significantly wider when Erg rather than cholesterol (Chol) was used as the sterol component. We used machine learning for the first time to analyze microscopic images of cell-sized liposomes and identify phase-separated structures. The automated method was successful in identifying homogeneous membranes but performance remained data-limited for the identification of phase separation domains characterized by more complex features.
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Affiliation(s)
- Tsuyoshi Yoda
- Aomori Prefectural Industrial Technology Research Center, Hachinohe Industrial Research Institute, Hachinohe City, Aomori 039-2245, Japan
- The United Graduate School of Agricultural Sciences, Iwate University, Morioka City, Iwate 020-8550, Japan
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10
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Liu Y, Yang G, Hui Y, Ranaweera S, Zhao CX. Microfluidic Nanoparticles for Drug Delivery. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2106580. [PMID: 35396770 DOI: 10.1002/smll.202106580] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Nanoparticles (NPs) have attracted tremendous interest in drug delivery in the past decades. Microfluidics offers a promising strategy for making NPs for drug delivery due to its capability in precisely controlling NP properties. The recent success of mRNA vaccines using microfluidics represents a big milestone for microfluidic NPs for pharmaceutical applications, and its rapid scaling up demonstrates the feasibility of using microfluidics for industrial-scale manufacturing. This article provides a critical review of recent progress in microfluidic NPs for drug delivery. First, the synthesis of organic NPs using microfluidics focusing on typical microfluidic methods and their applications in making popular and clinically relevant NPs, such as liposomes, lipid NPs, and polymer NPs, as well as their synthesis mechanisms are summarized. Then, the microfluidic synthesis of several representative inorganic NPs (e.g., silica, metal, metal oxide, and quantum dots), and hybrid NPs is discussed. Lastly, the applications of microfluidic NPs for various drug delivery applications are presented.
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Affiliation(s)
- Yun Liu
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Guangze Yang
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Yue Hui
- Institute of Advanced Technology, Westlake University, Hangzhou, Zhejiang, 310024, China
| | - Supun Ranaweera
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Chun-Xia Zhao
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia
- School of Chemical Engineering and Advanced Materials, Faculty of Engineering, Computer and Mathematical Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia
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11
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Foley SL, Hossein A, Deserno M. Fluid-gel coexistence in lipid membranes under differential stress. Biophys J 2022; 121:2997-3009. [PMID: 35859420 PMCID: PMC9463654 DOI: 10.1016/j.bpj.2022.07.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/03/2022] [Accepted: 07/12/2022] [Indexed: 11/21/2022] Open
Abstract
A widely conserved property of many biological lipid bilayers is their asymmetry. In addition to having distinct compositions on its two sides, a membrane can also exhibit different tensions in its two leaflets, a state known as differential stress. Here, we examine how this stress can influence the phase behavior of the constituent lipid monolayers of a single-component membrane. For temperatures sufficiently close to, but still above, the main transition, molecular dynamics simulations show the emergence of finite gel domains within the compressed leaflet. We describe the thermodynamics of this phenomenon by adding two empirical single-leaflet free energies for the fluid-gel transition, each evaluated at its respective asymmetry-dependent lipid density. Finite size effects arising in simulation are included in the theory through a geometry-dependent interfacial term. Our model reproduces the phase coexistence observed in simulation. It could therefore be used to connect the "hidden variable" of differential stress to experimentally observable properties of the main phase transition. These ideas could be generalized to any first-order bilayer phase transition in the presence of asymmetry, including liquid-ordered/liquid-disordered phase separation.
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Affiliation(s)
- Samuel L Foley
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Amirali Hossein
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania; Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Markus Deserno
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania.
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12
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Kataoka-Hamai C, Kawakami K. Hydrocarbon Penetration into Phospholipid Monolayers Formed at Hydrocarbon-Water Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:3720-3728. [PMID: 35289166 DOI: 10.1021/acs.langmuir.1c03269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Phospholipid monolayers formed at oil-water interfaces are used for various biological applications. However, monolayer structures are not well understood. Herein, we investigated hydrocarbon partitioning in 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine monolayers formed at hydrocarbon-water interfaces using fluorescence microscopy and pendant drop tensiometry. The monolayers strongly interacted with squalene, n-hexadecane, n-tetradecane, n-dodecane, n-decane, and n-butylcyclohexane. These alkane and alkylcyclohexane molecules remained within the monolayers during area compression. In contrast, the monolayers interacted weakly with n-pentylbenzene and n-butylbenzene. These alkylbenzenes were gradually removed from the monolayers upon area compression and were completely expelled at an area per lipid of ∼70 Å2. Surface pressure analysis indicated that the ability of hydrocarbons to penetrate the monolayers was enhanced in the order of n-butylbenzene < n-pentylbenzene < n-butylcyclohexane < n-hexadecane.
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Affiliation(s)
- Chiho Kataoka-Hamai
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Kohsaku Kawakami
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
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13
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Yoda T. Quality Evaluation of Drinks Based on Liposome Shape Changes Induced by Flavor Molecules. ACS OMEGA 2022; 7:5679-5686. [PMID: 35224329 PMCID: PMC8867555 DOI: 10.1021/acsomega.1c04946] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 01/27/2022] [Indexed: 05/27/2023]
Abstract
The flavors of ethyl caproate and isoamyl acetate and their precursors are crucial in sake brewing for fermentation and evaluation of the corresponding quality of drinks. However, the quality evaluation of drinks containing these flavors is challenging. Therefore, sake quality was evaluated via dynamic membrane transformation on cell-sized liposomes while adding flavor-containing solutions. Flavor varieties have been reported to influence dynamic shape change patterns. This study reports the observed difference in the dynamic shape change of each flavor. Based on these results, proper quality evaluation of drinks is expected.
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Affiliation(s)
- Tsuyoshi Yoda
- Aomori
Prefectural Industrial Technology Research Center, Hirosaki Industrial Research Institute, 1-1-8 Ougi-machi, Hirosaki
City, Aomori 036-8104, Japan
- Aomori
Prefectural Industrial Technology Research Center, Hachinohe Industrial Research Institute, 1-4-43 Kita-inter-kogyodanchi, Hachinohe City, Aomori 039-2245, Japan
- The
United Graduate School of Agricultural Sciences, Iwate University, 3-18-8,
Ueda, Morioka City, Iwate 020-8550, Japan
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14
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Effects of isovaleraldehyde on cell-sized lipid bilayer vesicles. Biophys Chem 2021; 279:106698. [PMID: 34644672 DOI: 10.1016/j.bpc.2021.106698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 10/05/2021] [Indexed: 11/23/2022]
Abstract
Membrane composition and components are intrinsic properties of a cell membrane. Any changes in lipid vesicle composition or any stimuli, such as heat, that affect molecular packing induce dynamic shape change. Dynamic shape changes allow the determination of structural organization changes upon a change in the membrane internal or external environment. In this study, we report how thermal stress can affect isovaleraldehyde (IVA) flavor compound-containing membranes. We revealed that (1) IVA-containing lipid vesicles are large and their increasing size results in increasing IVA/vesicle concentration; (2) IVA-containing lipid vesicles are less thermo-responsive and are affected by increasing IVA concentration; finally, we discussed (3) the molecular mechanisms behind membrane packing. We proposed that the characteristic of IVA-containing membranes could be used in evaluating drink quality. Our results would potentially contribute to the development of membrane technology and the progress in further understanding physiological processes, such as flavor sensation.
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15
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Takahashi H, Ogawa A. A Detailed Protocol for Preparing Millimeter-sized Supergiant Liposomes that Permit Efficient Eukaryotic Cell-free Translation in the Interior. Bio Protoc 2021; 11:e4054. [PMID: 34262997 DOI: 10.21769/bioprotoc.4054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/29/2021] [Accepted: 03/29/2021] [Indexed: 11/02/2022] Open
Abstract
Liposomes have been used as a pseudo cell membrane for encapsulating biomolecules and creating an artificial cell in the interior where biochemical reactions can occur. Among the several methods used to prepare biomolecule-encapsulating liposomes, the spontaneous emulsion transfer method is superior to others in that it allows us to readily prepare relatively large liposomes whose sizes are controlled (from micrometer- to millimeter-sized liposomes) without special equipment. However, conventional protocols for this method require liposomes to contain a considerably high concentration of sucrose (high-density solute), which severely inhibits gene expression, one of the most important biochemical reactions. Thus, we optimized the preparation conditions to develop a wheat germ extract (WGE)-based protocol that requires a much lower concentration of sucrose and has almost no effect on eukaryotic cell-free translation. Our protocol allows us to successfully prepare millimeter-sized, moderately stable, WGE-encapsulating liposomes in which WGE translation takes place efficiently. Since a broad range of genes derived from various types of organisms can be efficiently translated in a WGE-based translation system, liposomes prepared using our protocol would be useful as a versatile research tool for artificial cells.
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Affiliation(s)
| | - Atsushi Ogawa
- Proteo-Science Center, Ehime University, Matsuyama, Japan
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16
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Parperis C, Wallace MI. Single-molecule imaging of pore-forming toxin dynamics in droplet interface bilayers. Methods Enzymol 2021; 649:431-459. [PMID: 33712195 DOI: 10.1016/bs.mie.2021.01.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Single-channel recording from pore-forming toxins (PFTs) provides a clear and direct molecular readout of toxin action. However to complete any mechanistic understanding of PFT behavior, this functional kinetic readout must be linked to the underlying changes in toxin structure, binding, conformation, or stoichiometry. Here we review how single-molecule imaging methods might be used to further our understanding of PFTs, and provide detailed practical guidance on the use of droplet interface bilayers as a method capable of examining both single-molecule fluorescence and single-channel electrical signals from PFTs.
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Affiliation(s)
- Christopher Parperis
- Department of Chemistry, Britannia House, King's College London, London, United Kingdom
| | - Mark I Wallace
- Department of Chemistry, Britannia House, King's College London, London, United Kingdom.
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17
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Hossein A, Deserno M. Stiffening transition in asymmetric lipid bilayers: The role of highly ordered domains and the effect of temperature and size. J Chem Phys 2021; 154:014704. [PMID: 33412863 DOI: 10.1063/5.0028255] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Cellular membranes consist of a large variety of lipids and proteins, with a composition that generally differs between the two leaflets of the same bilayer. One consequence of this asymmetry is thought to be the emergence of differential stress, i.e., a mismatch in the lateral tension of the two leaflets. This can affect a membrane's mechanical properties; for instance, it can increase the bending rigidity once the differential stress exceeds a critical threshold. Using coarse-grained molecular dynamics simulations based on the MARTINI model, we show that this effect arises due to the formation of more highly ordered domains in the compressed leaflet. The threshold asymmetry increases with temperature, indicating that the transition to a stiffened regime might be restricted to a limited temperature range above the gel transition. We also show that stiffening occurs more readily for larger membranes with smaller typical curvatures, suggesting that the stiffening transition is easier to observe experimentally than in the small-scale systems accessible to simulation.
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Affiliation(s)
- Amirali Hossein
- Department of Physics, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, Pennsylvania 15213, USA
| | - Markus Deserno
- Department of Physics, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, Pennsylvania 15213, USA
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18
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Yoda T, Saito T. Size of Cells and Physicochemical Properties of Membranes are Related to Flavor Production during Sake Brewing in the Yeast Saccharomyces cerevisiae. MEMBRANES 2020; 10:membranes10120440. [PMID: 33352892 PMCID: PMC7766171 DOI: 10.3390/membranes10120440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 12/17/2022]
Abstract
Ethyl caproate (EC) and isoamyl acetate (IA) are key flavor components of sake. Recently, attempts have been made to increase the content of good flavor components, such as EC and IA, in sake brewing. However, the functions of EC and IA in yeast cells remain poorly understood. Therefore, we investigated the effects of EC and IA using cell-sized lipid vesicles. We also investigated lipid vesicles containing EC and/or caproic acid (CA) as well as IA and/or isoamyl alcohol (IAA). CA and IAA are precursors of EC and IA, respectively, and are important flavors in sake brewing. The size of a vesicle is influenced by flavor compounds and their precursors in a concentration-dependent manner. We aimed to establish the conditions in which the vesicles contained more flavors simultaneously and with different ratios. Interestingly, vesicles were largest in a mixture of 50% of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) with 25% EC and 25% CA or a mixture of 50% DOPC with 25% IA and 25% IAA. The impact of flavor additives on membrane fluidity was also studied using Laurdan generalized polarization. During the production process, flavors may regulate the fluidity of lipid membranes.
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Affiliation(s)
- Tsuyoshi Yoda
- Aomori Prefectural Industrial Technology Research Center, Hirosaki Industrial Research Institute, 1-1-8 Ougi-machi, Hirosaki, Aomori 036-8104, Japan;
- The United Graduate School of Agricultural Sciences, Iwate University, 3-18-8, Ueda, Morioka 020-8550, Japan
- Correspondence: ; Tel.: +81-172-55-6740
| | - Tomoaki Saito
- Aomori Prefectural Industrial Technology Research Center, Hirosaki Industrial Research Institute, 1-1-8 Ougi-machi, Hirosaki, Aomori 036-8104, Japan;
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19
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Foley S, Deserno M. Stabilizing Leaflet Asymmetry under Differential Stress in a Highly Coarse-Grained Lipid Membrane Model. J Chem Theory Comput 2020; 16:7195-7206. [PMID: 33126796 DOI: 10.1021/acs.jctc.0c00862] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We present a version of the coarse-grained Cooke lipid model, modified to simulate asymmetric lipid membranes. It is inspired by a method employed by Wang et al. [ Commun. Comput. Phys. 2013, 13, 1093-1106] for artificially penalizing lipid flip-flop but copes more robustly with differential stress, at the cost of one additional bead per lipid and the concomitant increase in computational overhead. Bilayer asymmetry ultimately breaks down beyond a system size dependent critical differential stress, which can be predicted from a simple analytical model. We remeasure many important material parameters for the new model and find it to be consistent with typical fluid lipid membranes. Maintaining a stable stress asymmetry has many applications, and we give two examples: (i) connecting monolayer stress to lipid number asymmetry in order to directly measure the monolayer area modulus and (ii) finding its strain-dependent higher-order correction by monitoring the equilibrium bilayer area.
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Affiliation(s)
- Samuel Foley
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Markus Deserno
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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20
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Takahashi H, Ogawa A. Preparation of a Millimeter-Sized Supergiant Liposome That Allows for Efficient, Eukaryotic Cell-Free Translation in the Interior by Spontaneous Emulsion Transfer. ACS Synth Biol 2020; 9:1608-1614. [PMID: 32559381 DOI: 10.1021/acssynbio.0c00173] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We sought to prepare millimeter-sized supergiant unilamellar vesicles (SGUVs) by spontaneous emulsion transfer for efficient, eukaryotic cell-free translation in the interior. Although the conventional protocols require that a considerably high concentration of sucrose be encapsulated into the SGUVs for their efficient formation, such high amounts of sucrose severely inhibited cell-free translation based on wheat germ extract (WGE). We thus optimized the preparation conditions to permit SGUV formation at a much lower concentration of sucrose that has almost no effect on WGE translation. Under the optimized conditions, we successfully prepared WGE translation system-encapsulating SGUVs that allow for protein synthesis with a high efficiency comparable to that outside a liposome. The optimization also resulted in a high rate of successful SGUV formation (>90%) and a decent stability of the formed SGUVs (>60 min). These SGUVs are expected to serve as research tools in cell-free synthetic biology and as foundations for artificial cell-based biosensors.
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Affiliation(s)
- Hajime Takahashi
- Proteo-Science Center, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Atsushi Ogawa
- Proteo-Science Center, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
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21
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Filipczak N, Pan J, Yalamarty SSK, Torchilin VP. Recent advancements in liposome technology. Adv Drug Deliv Rev 2020; 156:4-22. [PMID: 32593642 DOI: 10.1016/j.addr.2020.06.022] [Citation(s) in RCA: 249] [Impact Index Per Article: 62.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 06/16/2020] [Accepted: 06/21/2020] [Indexed: 12/22/2022]
Abstract
The liposomes have continued to be well-recognized as an important nano-sized drug delivery system with attractive properties, such a characteristic bilayer structure assembling the cellular membrane, easy-to-prepare and high bio-compatibility. Extensive effort has been devoted to the development of liposome-based drug delivery systems during the past few decades. Many drug candidates have been encapsulated in liposomes and investigated for reduced toxicity and extended duration of therapeutic effect. The liposomal encapsulation of hydrophilic and hydrophobic small molecule therapeutics as well as other large molecule biologics have been established among different academic and industrial research groups. To date, there has been an increasing number of FDA-approved liposomal-based therapeutics together with more and more undergoing clinical trials, which involve a wide range of applications in anticancer, antibacterial, and antiviral therapies. In order to meet the continuing demand for new drugs in clinics, more recent advancements have been investigated for optimizing liposomal-based drug delivery system with more reproducible preparation technique and a broadened application to novel modalities, including nucleic acid therapies, CRISPR/Cas9 therapies and immunotherapies. This review focuses on the recent liposome' preparation techniques, the excipients of liposomal formulations used in various novel studies and the routes of administration used to deliver liposomes to targeted areas of disease. It aims to update the research in liposomal delivery and highlights future nanotechnological approaches.
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22
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Yandrapalli N, Seemann T, Robinson T. On-Chip Inverted Emulsion Method for Fast Giant Vesicle Production, Handling, and Analysis. MICROMACHINES 2020; 11:E285. [PMID: 32164221 PMCID: PMC7142477 DOI: 10.3390/mi11030285] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 01/25/2023]
Abstract
Liposomes and giant unilamellar vesicles (GUVs) in particular are excellent compartments for constructing artificial cells. Traditionally, their use requires bench-top vesicle growth, followed by experimentation under a microscope. Such steps are time-consuming and can lead to loss of vesicles when they are transferred to an observation chamber. To overcome these issues, we present an integrated microfluidic chip which combines GUV formation, trapping, and multiple separate experiments in the same device. First, we optimized the buffer conditions to maximize both the yield and the subsequent trapping of the vesicles in micro-posts. Captured GUVs were monodisperse with specific size of 18 ± 4 µm in diameter. Next, we introduce a two-layer design with integrated valves which allows fast solution exchange in less than 20 s and on separate sub-populations of the trapped vesicles. We demonstrate that multiple experiments can be performed in a single chip with both membrane transport and permeabilization assays. In conclusion, we have developed a versatile all-in-one microfluidic chip with capabilities to produce and perform multiple experiments on a single batch of vesicles using low sample volumes. We expect this device will be highly advantageous for bottom-up synthetic biology where rapid encapsulation and visualization is required for enzymatic reactions.
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Affiliation(s)
| | | | - Tom Robinson
- Department of Theory & Bio-Systems, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
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23
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Petukhov MV, Konarev PV, Dadinova LA, Fedorova NV, Volynsky PE, Svergun DI, Batishchev OV, Shtykova EV. Quasi-Atomistic Approach to Modeling of Liposomes. CRYSTALLOGR REP+ 2020. [DOI: 10.1134/s1063774520020182] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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24
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Konarev PV, Petoukhov MV, Dadinova LA, Fedorova NV, Volynsky PE, Svergun DI, Batishchev OV, Shtykova EV. BILMIX: a new approach to restore the size polydispersity and electron density profiles of lipid bilayers from liposomes using small-angle X-ray scattering data. J Appl Crystallogr 2020. [DOI: 10.1107/s1600576719015656] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Small-angle X-ray scattering (SAXS) is one of the major tools for the study of model membranes, but interpretation of the scattering data remains non-trivial. Current approaches allow the extraction of some structural parameters and the electron density profile of lipid bilayers. Here it is demonstrated that parametric modelling can be employed to determine the polydispersity of spherical or ellipsoidal vesicles and describe the electron density profile across the lipid bilayer. This approach is implemented in the computer program BILMIX. BILMIX delivers a description of the electron density of a lipid bilayer from SAXS data and simultaneously generates the corresponding size distribution of the unilamellar lipid vesicles.
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25
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Hossein A, Deserno M. Spontaneous Curvature, Differential Stress, and Bending Modulus of Asymmetric Lipid Membranes. Biophys J 2019; 118:624-642. [PMID: 31954503 DOI: 10.1016/j.bpj.2019.11.3398] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/20/2019] [Accepted: 11/25/2019] [Indexed: 12/24/2022] Open
Abstract
Lipid bilayers can exhibit asymmetric states, in which the physical characteristics of one leaflet differ from those of the other. This most visibly manifests in a different lipid composition, but it can also involve opposing lateral stresses in each leaflet that combine to an overall vanishing membrane tension. Here, we use theoretical modeling and coarse-grained simulation to explore the interplay between a compositional asymmetry and a nonvanishing differential stress. Minimizing the total elastic energy leads to a preferred spontaneous curvature that balances torques due to both bending moments and differential stress, with sometimes unexpected consequences. For instance, asymmetric flat bilayers, whose specific areas in each leaflet are matched to those of corresponding tensionless symmetric flat membranes, still exhibit a residual differential stress because the conditions of vanishing area strain and vanishing bending moment differ. We also measure the curvature rigidity of asymmetric bilayers and find that a sufficiently strong differential stress, but not compositional asymmetry alone, can increase the bending modulus. The likely cause is a stiffening of the compressed leaflet, which appears to be related to its gel transition but not identical with it. We finally show that the impact of cholesterol on differential stress depends on the relative strength of elastic and thermodynamic driving forces: if cholesterol solvates equally well in both leaflets, it will redistribute to cancel both leaflet tensions almost completely, but if its partitioning free energy prefers one leaflet over the other, the resulting distribution bias may even create differential stress. Because cells keep most of their lipid bilayers in an asymmetric nonequilibrium steady state, our findings suggest that biomembranes are elastically more complex than previously thought: besides a spontaneous curvature, they might also exhibit significant differential stress, which could strongly affect their curvature energetics.
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Affiliation(s)
- Amirali Hossein
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Markus Deserno
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania.
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26
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Abstract
The lipid bilayer, together with embedded proteins, is the central structure in biomembranes. While artificial lipid bilayers are useful to model natural membranes, they are generally symmetric, with the same membrane lipid composition in each lipid monolayer (leaflet). In contrast, natural membranes are often asymmetric, with different lipids in each leaflet. To prepare asymmetric lipid vesicles, we developed cyclodextrin-catalyzed phospholipid exchange procedures. The basic method is that an excess of vesicles with one set of lipids (the donor vesicles) is mixed with a second set of vesicles (acceptor vesicles) with a different set of lipids. Cyclodextrin is introduced into the external aqueous solution, so that lipids in the outer leaflet of the vesicles bind to it and are shuttled between the vesicles. At equilibrium, the lipids in the outer leaflet of the acceptor vesicles are replaced by those from the donor vesicles. The exchanged acceptor vesicles are then isolated. Asymmetric vesicles are versatile in terms of vesicle sizes and lipid compositions that can be prepared. Measuring asymmetry is often difficult. A variety of assays can be used to measure the extent of asymmetry, but most are specific for one particular membrane lipid type or class, and there are none that can be used in all situations. Studies using asymmetric vesicles have begun to explore how asymmetry influences lipid movement across the bilayer, the formation of ordered lipid domains, coupling between the physical properties in each leaflet, and membrane protein conformation. Lipid domain formation stands out as one of the most important properties in which asymmetry is likely to be crucial. Lipid bilayers can exist in both liquidlike and solid/ordered-like states depending on lipid structure, and in lipid vesicles with a mixture of lipids highly ordered and disordered domains can coexist. However, until very recently, such studies only had been carried out in symmetric artificial membranes. Whether ordered domains (often called lipid rafts) and disordered lipid domains coexist in asymmetric cell membranes remains controversial partly because lipids favoring the formation of an ordered state are largely restricted to the leaflet facing the external environment. Studies using asymmetric vesicles have recently shown that each leaflet can influence the physical behavior of the other, i.e., that the domain forming properties in each leaflet tend to be coupled, with consequences highly dependent upon the details of lipid structure. Future studies investigating the dependence of coupling and properties upon the details of lipid composition should clarify the potential of natural membranes to form lipid domains. In addition, we recently extended the exchange method to living mammalian cells, using exchange to efficiently replace virtually the entire phospholipid and sphingolipid population of the plasma membrane outer leaflet with exogenous lipids without harming cells. This should allow detailed studies of the functional impact of lipid structure, asymmetry, domain organization, and interactions with membrane proteins in living cells.
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Affiliation(s)
- Erwin London
- Department of Biochemistry and Cell Biology and Department of Chemistry Stony Brook University, Stony Brook, New York 11794, United States
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27
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Stano P. Gene Expression Inside Liposomes: From Early Studies to Current Protocols. Chemistry 2019; 25:7798-7814. [DOI: 10.1002/chem.201806445] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Indexed: 12/26/2022]
Affiliation(s)
- Pasquale Stano
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA)University of Salento, Ecotekne 73100 Lecce Italy
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28
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de Matos MBC, Miranda BS, Rizky Nuari Y, Storm G, Leneweit G, Schiffelers RM, Kok RJ. Liposomes with asymmetric bilayers produced from inverse emulsions for nucleic acid delivery. J Drug Target 2019; 27:681-689. [DOI: 10.1080/1061186x.2019.1579819] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Maria B. C. de Matos
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | | | - Yudha Rizky Nuari
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Gert Storm
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | | | - Raymond M. Schiffelers
- Laboratory Clinical Chemistry & Haematology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Robbert J. Kok
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
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29
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Matsushita-Ishiodori Y, Hanczyc MM, Wang A, Szostak JW, Yomo T. Using Imaging Flow Cytometry to Quantify and Optimize Giant Vesicle Production by Water-in-oil Emulsion Transfer Methods. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:2375-2382. [PMID: 30645943 DOI: 10.1021/acs.langmuir.8b03635] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Many biologists, biochemists, and biophysicists study giant vesicles, which have a diameter of >1 μm, owing to their ease of characterization using standard optical methods. More recently, there has been interest in using giant vesicles as model systems for living cells and for the construction of artificial cells. In fact, there have been a number of reports about functionalizing giant vesicles using membrane-bound pore proteins and encapsulating biochemical reactions. Among the various methods for preparing giant vesicles, the water-in-oil emulsion transfer method is particularly well established. However, the giant vesicles prepared by this method have complex and heterogeneous properties, such as particle size and membrane structure. Here, we demonstrate the characterization of giant vesicles by imaging flow cytometry to provide quantitative and qualitative information about the vesicle products prepared by the water-in-oil emulsion transfer method. Through image-based analyses, several kinds of protocol byproducts, such as oil droplets and vesicles encapsulating no target molecules, were identified and successfully quantified. Further, the optimal agitation conditions for the water-in-oil emulsion transfer method were found from detailed analysis of imaging flow cytometry data. Our results indicate that a sonication-based water-in-oil emulsion transfer method exhibited a higher efficiency in producing giant vesicles, about 10 times or higher than that of vortex and rumble strip-based methods. It is anticipated that these approaches will be useful for fine-tuning giant vesicle production and subsequent applications.
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Affiliation(s)
- Yuka Matsushita-Ishiodori
- Institute of Biology and Information Science, School of Computer Science and Software Engineering, School of Life Sciences , East China Normal University , Shanghai 200062 , PR China
| | - Martin M Hanczyc
- Laboratory for Artificial Biology, Centre for Integrative Biology (CIBIO) , University of Trento , 38122 , Trento , Italy
- Chemical and Biological Engineering , University of New Mexico , Albuquerque , New Mexico 87131 , United States
| | - Anna Wang
- Department of Molecular Biology , Massachusetts General Hospital , Boston , Massachusetts 02114 , United States
- Center for Computational and Integrative Biology , Massachusetts General Hospital , Boston , Massachusetts 02114 , United States
| | - Jack W Szostak
- Department of Molecular Biology , Massachusetts General Hospital , Boston , Massachusetts 02114 , United States
- Department of Genetics , Harvard Medical School , Boston , Massachusetts 02115 , United States
- Center for Computational and Integrative Biology , Massachusetts General Hospital , Boston , Massachusetts 02114 , United States
| | - Tetsuya Yomo
- Institute of Biology and Information Science, School of Computer Science and Software Engineering, School of Life Sciences , East China Normal University , Shanghai 200062 , PR China
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30
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Tsuji G, Sunami T, Ichihashi N. Production of giant unilamellar vesicles by the water-in-oil emulsion-transfer method without high internal concentrations of sugars. J Biosci Bioeng 2018; 126:540-545. [DOI: 10.1016/j.jbiosc.2018.04.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 04/24/2018] [Accepted: 04/26/2018] [Indexed: 10/16/2022]
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31
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Altamura E, Carrara P, D'Angelo F, Mavelli F, Stano P. Extrinsic stochastic factors (solute partition) in gene expression inside lipid vesicles and lipid-stabilized water-in-oil droplets: a review. Synth Biol (Oxf) 2018; 3:ysy011. [PMID: 32995519 PMCID: PMC7445889 DOI: 10.1093/synbio/ysy011] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 06/18/2018] [Accepted: 06/21/2018] [Indexed: 11/13/2022] Open
Abstract
The encapsulation of transcription-translation (TX-TL) machinery inside lipid vesicles and water-in-oil droplets leads to the construction of cytomimetic systems (often called 'synthetic cells') for synthetic biology and origins-of-life research. A number of recent reports have shown that protein synthesis inside these microcompartments is highly diverse in terms of rate and amount of synthesized protein. Here, we discuss the role of extrinsic stochastic effects (i.e. solute partition phenomena) as relevant factors contributing to this pattern. We evidence and discuss cases where between-compartment diversity seems to exceed the expected theoretical values. The need of accurate determination of solute content inside individual vesicles or droplets is emphasized, aiming at validating or rejecting the predictions calculated from the standard fluctuations theory. At the same time, we promote the integration of experiments and stochastic modeling to reveal the details of solute encapsulation and intra-compartment reactions.
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Affiliation(s)
- Emiliano Altamura
- Chemistry Department, University of Bari, Via E. Orabona 4, I-70126, Bari, Italy
| | - Paolo Carrara
- Department of Sciences, Roma Tre University, Viale G. Marconi 446, I-00146, Rome, Italy
| | - Francesca D'Angelo
- Department of Sciences, Roma Tre University, Viale G. Marconi 446, I-00146, Rome, Italy
| | - Fabio Mavelli
- Chemistry Department, University of Bari, Via E. Orabona 4, I-70126, Bari, Italy
| | - Pasquale Stano
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Ecotekne, I-73100, Lecce, Italy
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32
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Karamdad K, Hindley JW, Bolognesi G, Friddin MS, Law RV, Brooks NJ, Ces O, Elani Y. Engineering thermoresponsive phase separated vesicles formed via emulsion phase transfer as a content-release platform. Chem Sci 2018; 9:4851-4858. [PMID: 29910937 PMCID: PMC5982195 DOI: 10.1039/c7sc04309k] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 04/22/2018] [Indexed: 01/20/2023] Open
Abstract
Elucidation of cholesterol insertion efficiency into phase-transfer vesicles enables the rational design of phase-separated membranes as thermally-responsive platforms for artificial cell construction.
Giant unilamellar vesicles (GUVs) are a well-established tool for the study of membrane biophysics and are increasingly used as artificial cell models and functional units in biotechnology. This trend is driven by the development of emulsion-based generation methods such as Emulsion Phase Transfer (EPT), which facilitates the encapsulation of almost any water-soluble compounds (including biomolecules) regardless of size or charge, is compatible with droplet microfluidics, and allows GUVs with asymmetric bilayers to be assembled. However, the ability to control the composition of membranes formed via EPT remains an open question; this is key as composition gives rise to an array of biophysical phenomena which can be used to add functionality to membranes. Here, we evaluate the use of GUVs constructed via this method as a platform for phase behaviour studies and take advantage of composition-dependent features to engineer thermally-responsive GUVs. For the first time, we generate ternary GUVs (DOPC/DPPC/cholesterol) using EPT, and by compensating for the lower cholesterol incorporation efficiencies, show that these possess the full range of phase behaviour displayed by electroformed GUVs. As a demonstration of the fine control afforded by this approach, we demonstrate release of dye and peptide cargo when ternary GUVs are heated through the immiscibility transition temperature, and show that release temperature can be tuned by changing vesicle composition. We show that GUVs can be individually addressed and release triggered using a laser beam. Our findings validate EPT as a suitable method for generating phase separated vesicles and provide a valuable proof-of-concept for engineering content release functionality into individually addressable vesicles, which could have a host of applications in the development of smart synthetic biosystems.
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Affiliation(s)
- Kaiser Karamdad
- Department of Chemistry , Imperial College London , Exhibition Road , London , SW7 2AZ , UK . ; .,Institute of Chemical Biology , Imperial College London , Exhibition Road , London , SW7 2AZ , UK
| | - James W Hindley
- Department of Chemistry , Imperial College London , Exhibition Road , London , SW7 2AZ , UK . ; .,Institute of Chemical Biology , Imperial College London , Exhibition Road , London , SW7 2AZ , UK
| | - Guido Bolognesi
- Department of Chemical Engineering , Loughborough University , Loughborough , LE11 3TU , UK
| | - Mark S Friddin
- Department of Chemistry , Imperial College London , Exhibition Road , London , SW7 2AZ , UK . ;
| | - Robert V Law
- Department of Chemistry , Imperial College London , Exhibition Road , London , SW7 2AZ , UK . ; .,Institute of Chemical Biology , Imperial College London , Exhibition Road , London , SW7 2AZ , UK
| | - Nicholas J Brooks
- Department of Chemistry , Imperial College London , Exhibition Road , London , SW7 2AZ , UK . ; .,Institute of Chemical Biology , Imperial College London , Exhibition Road , London , SW7 2AZ , UK
| | - Oscar Ces
- Department of Chemistry , Imperial College London , Exhibition Road , London , SW7 2AZ , UK . ; .,Institute of Chemical Biology , Imperial College London , Exhibition Road , London , SW7 2AZ , UK.,FABRICELL , Imperial College London , Exhibition Road , London , SW7 2AZ , UK
| | - Yuval Elani
- Department of Chemistry , Imperial College London , Exhibition Road , London , SW7 2AZ , UK . ; .,Institute of Chemical Biology , Imperial College London , Exhibition Road , London , SW7 2AZ , UK.,FABRICELL , Imperial College London , Exhibition Road , London , SW7 2AZ , UK
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Peyret A, Zhao H, Lecommandoux S. Preparation and Properties of Asymmetric Synthetic Membranes Based on Lipid and Polymer Self-Assembly. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:3376-3385. [PMID: 29486556 DOI: 10.1021/acs.langmuir.7b04233] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Cell membrane asymmetry is a common structural feature of all biological cells. Researchers have tried for decades to better study its formation and its function in membrane-regulated phenomena. In particular, there has been increasing interest in developing synthetic asymmetric membrane models in the laboratory, with the aim of studying basic physical chemistry properties that may be correlated to a relevant biological function. The present article aims to summarize the main presented approaches to prepare asymmetric membranes, which are most often made from lipids, polymers, or a combination of both.
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Affiliation(s)
- Ariane Peyret
- Laboratoire de Chimie des Polymères Organiques, LCPO, Université de Bordeaux, CNRS, Bordeaux INP, UMR 5629 , 16 Avenue Pey Berland F-33600 Pessac , France
| | - Hang Zhao
- Laboratoire de Chimie des Polymères Organiques, LCPO, Université de Bordeaux, CNRS, Bordeaux INP, UMR 5629 , 16 Avenue Pey Berland F-33600 Pessac , France
| | - Sébastien Lecommandoux
- Laboratoire de Chimie des Polymères Organiques, LCPO, Université de Bordeaux, CNRS, Bordeaux INP, UMR 5629 , 16 Avenue Pey Berland F-33600 Pessac , France
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Abstract
A multipass transmembrane (MTM) structure is prevalent in membrane proteins for a wide range of functions. Typically, the MTM structure is constructed of bundled multiple α-helices spanning the membrane which are connected by flexible domains. One characteristic feature of MTM proteins is dynamic functions such as stimuli responses and conformational changes. In this review, the development of synthetic molecules forming an MTM structure in membranes is highlighted. The MTM folded structure is developed using an amphiphilic molecular design with a multiblock strategy between rigid hydrophobic components and flexible hydrophilic units. Such synthetic amphiphiles not only form the MTM structure by folding but also self-assemble to construct supramolecular ion channels. An elaborated molecular design of the MTM structure with a ligand-binding pocket allows for ligand-gated regulation of ion transport. Light-triggered membrane deformation for vesicle budding is also demonstrated.
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Affiliation(s)
- Takahiro Muraoka
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology
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35
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Peyret A, Ibarboure E, Le Meins J, Lecommandoux S. Asymmetric Hybrid Polymer-Lipid Giant Vesicles as Cell Membrane Mimics. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1700453. [PMID: 29375971 PMCID: PMC5770682 DOI: 10.1002/advs.201700453] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/17/2017] [Indexed: 05/29/2023]
Abstract
Lipid membrane asymmetry plays an important role in cell function and activity, being for instance a relevant signal of its integrity. The development of artificial asymmetric membranes thus represents a key challenge. In this context, an emulsion-centrifugation method is developed to prepare giant vesicles with an asymmetric membrane composed of an inner monolayer of poly(butadiene)-b-poly(ethylene oxide) (PBut-b-PEO) and outer monolayer of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). The formation of a complete membrane asymmetry is demonstrated and its stability with time is followed by measuring lipid transverse diffusion. From fluorescence spectroscopy measurements, the lipid half-life is estimated to be 7.5 h. Using fluorescence recovery after photobleaching technique, the diffusion coefficient of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(lissamine rhodamine B sulfonyl) (DOPE-rhod, inserted into the POPC leaflet) is determined to be about D = 1.8 ± 0.50 μm2 s-1 at 25 °C and D = 2.3 ± 0.7 μm2 s-1 at 37 °C, between the characteristic values of pure POPC and pure polymer giant vesicles and in good agreement with the diffusion of lipids in a variety of biological membranes. These results demonstrate the ability to prepare a cell-like model system that displays an asymmetric membrane with transverse and translational diffusion properties similar to that of biological cells.
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Affiliation(s)
- Ariane Peyret
- Laboratoire de Chimie des Polymères OrganiquesLCPOUniversité de BordeauxCNRSBordeaux INPUMR 562916 Avenue Pey BerlandF‐33600PessacFrance
| | - Emmanuel Ibarboure
- Laboratoire de Chimie des Polymères OrganiquesLCPOUniversité de BordeauxCNRSBordeaux INPUMR 562916 Avenue Pey BerlandF‐33600PessacFrance
| | - Jean‐François Le Meins
- Laboratoire de Chimie des Polymères OrganiquesLCPOUniversité de BordeauxCNRSBordeaux INPUMR 562916 Avenue Pey BerlandF‐33600PessacFrance
| | - Sebastien Lecommandoux
- Laboratoire de Chimie des Polymères OrganiquesLCPOUniversité de BordeauxCNRSBordeaux INPUMR 562916 Avenue Pey BerlandF‐33600PessacFrance
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36
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Sommerling JH, Uhlenbruck N, Leneweit G, Nirschl H. Transfer of colloidal particles between two non-miscible liquid phases. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2017.08.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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37
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Stano P, Altamura E, Mavelli F. Novel directions in molecular systems design: The case of light-transducing synthetic cells. Commun Integr Biol 2017; 10:e1365993. [PMID: 29260799 PMCID: PMC5731512 DOI: 10.1080/19420889.2017.1365993] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/04/2017] [Accepted: 08/04/2017] [Indexed: 12/01/2022] Open
Abstract
Important progresses have been achieved in the past years in the field of bottom-up synthetic biology, especially aiming at constructing cell-like systems based on lipid vesicles (liposomes) entrapping both biomolecules or synthetic compounds. These "synthetic cells" mimic the behaviour of biological cells but are constituted by a minimal number of components. One key aspect related to this research is the energetic needs of synthetic cells. Up to now, high-energy compounds have been given in order to drive biochemical reactions inside the vesicle lumen. In order to be autonomous, synthetic cells must produce their own biochemical energy from available energy sources. At this aim we started a long-term research program focused on the construction of photoautotrophic synthetic cells, starting with the reconstitution, in active and highly oriented form, of the photosynthetic reaction centre in giant lipid vesicles (Altamura et al., PNAS 2017, 114, 3837-3842). Here we comment this first milestone by showing the synthetic biology context wherein it is developed, the future steps, and the experimental approach that might allow such an achievement.
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Affiliation(s)
- Pasquale Stano
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Ecotekne, Lecce, Italy
| | | | - Fabio Mavelli
- Chemistry Department, University “Aldo Moro,” Bari, Italy
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38
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Huang Y, Kim SH, Arriaga LR. Emulsion templated vesicles with symmetric or asymmetric membranes. Adv Colloid Interface Sci 2017; 247:413-425. [PMID: 28802479 DOI: 10.1016/j.cis.2017.07.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 07/13/2017] [Accepted: 07/13/2017] [Indexed: 10/19/2022]
Abstract
Emulsion droplets with well-controlled topologies are used as templates for forming vesicles with either symmetric or asymmetric membranes. This review summarizes the available technology to produce these templates, the strategies and critical parameters involved in the transformation of emulsion droplets into vesicles, and the properties of the generated vesicles, with a special focus on the composition and material distribution of the vesicle membrane. Here, we also address limitations in the field and point to future fundamental and applied research in the area.
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Iwamoto M, Oiki S. Membrane Perfusion of Hydrophobic Substances Around Channels Embedded in the Contact Bubble Bilayer. Sci Rep 2017; 7:6857. [PMID: 28761089 PMCID: PMC5537337 DOI: 10.1038/s41598-017-07048-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/20/2017] [Indexed: 11/12/2022] Open
Abstract
In fluidic biomembranes, lipids and membrane proteins diffuse restlessly, and lipid compositions change steadily. To mimic dynamic behavior of the biomembranes, a method for introducing rapid changes in the constituents in the lipid bilayer was developed. In contact bubble bilayers (CBB), as a water-in-oil droplet bilayer system, the bilayer hydrophobic interior is contiguous with the bulk oil phase. Making use of this geometrical feature as an access route, hydrophobic substances were administered into the bilayer. Polytheonamide B, a cytotoxic hydrophobic peptide, was applied, and oriented incorporation and relevant single-channel current recordings were enabled. Nystatin was pre-loaded in the CBB, and sterol perfusion exhibited slow development of the macroscopic current. On the contrary, the reconstituted KcsA potassium channels immediately attenuate the channel activity when cholesterol was applied. This oil-phase route in the CBB allows rapid perfusion of hydrophobic substances around the bilayer-embedded channels during continuous recordings of channel currents.
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Affiliation(s)
- Masayuki Iwamoto
- Department of Molecular Physiology and Biophysics, University of Fukui Faculty of Medical Sciences, 23-3 Matsuokashimoaizuki, Eiheiji-cho, Yoshida-gun, 910-1193, Fukui, Japan
| | - Shigetoshi Oiki
- Department of Molecular Physiology and Biophysics, University of Fukui Faculty of Medical Sciences, 23-3 Matsuokashimoaizuki, Eiheiji-cho, Yoshida-gun, 910-1193, Fukui, Japan.
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40
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Trantidou T, Friddin M, Elani Y, Brooks NJ, Law RV, Seddon JM, Ces O. Engineering Compartmentalized Biomimetic Micro- and Nanocontainers. ACS NANO 2017; 11:6549-6565. [PMID: 28658575 DOI: 10.1021/acsnano.7b03245] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Compartmentalization of biological content and function is a key architectural feature in biology, where membrane bound micro- and nanocompartments are used for performing a host of highly specialized and tightly regulated biological functions. The benefit of compartmentalization as a design principle is behind its ubiquity in cells and has led to it being a central engineering theme in construction of artificial cell-like systems. In this review, we discuss the attractions of designing compartmentalized membrane-bound constructs and review a range of biomimetic membrane architectures that span length scales, focusing on lipid-based structures but also addressing polymer-based and hybrid approaches. These include nested vesicles, multicompartment vesicles, large-scale vesicle networks, as well as droplet interface bilayers, and double-emulsion multiphase systems (multisomes). We outline key examples of how such structures have been functionalized with biological and synthetic machinery, for example, to manufacture and deliver drugs and metabolic compounds, to replicate intracellular signaling cascades, and to demonstrate collective behaviors as minimal tissue constructs. Particular emphasis is placed on the applications of these architectures and the state-of-the-art microfluidic engineering required to fabricate, functionalize, and precisely assemble them. Finally, we outline the future directions of these technologies and highlight how they could be applied to engineer the next generation of cell models, therapeutic agents, and microreactors, together with the diverse applications in the emerging field of bottom-up synthetic biology.
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Affiliation(s)
- Tatiana Trantidou
- Department of Chemistry and ‡Institute of Chemical Biology, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Mark Friddin
- Department of Chemistry and ‡Institute of Chemical Biology, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Yuval Elani
- Department of Chemistry and ‡Institute of Chemical Biology, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Nicholas J Brooks
- Department of Chemistry and ‡Institute of Chemical Biology, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Robert V Law
- Department of Chemistry and ‡Institute of Chemical Biology, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - John M Seddon
- Department of Chemistry and ‡Institute of Chemical Biology, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Oscar Ces
- Department of Chemistry and ‡Institute of Chemical Biology, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
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41
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Natsume Y, Wen HI, Zhu T, Itoh K, Sheng L, Kurihara K. Preparation of Giant Vesicles Encapsulating Microspheres by Centrifugation of a Water-in-oil Emulsion. J Vis Exp 2017:55282. [PMID: 28190062 PMCID: PMC5352288 DOI: 10.3791/55282] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The constructive biology and the synthetic biology approach to creating artificial life involve the bottom-up assembly of biological or nonbiological materials. Such approaches have received considerable attention in research on the boundary between living and nonliving matter and have been used to construct artificial cells over the past two decades. In particular, Giant Vesicles (GVs) have often been used as artificial cell membranes. In this paper, we describe the preparation of GVs encapsulating highly packed microspheres as a model of cells containing highly condensed biomolecules. The GVs were prepared by means of a simple water-in-oil emulsion centrifugation method. Specifically, a homogenizer was used to emulsify an aqueous solution containing the materials to be encapsulated and an oil containing dissolved phospholipids, and the resulting emulsion was layered carefully on the surface of another aqueous solution. The layered system was then centrifuged to generate the GVs. This powerful method was used to encapsulate materials ranging from small molecules to microspheres.
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Affiliation(s)
- Yuno Natsume
- Department of Mathematical and Physical Sciences, Faculty of Science, Japan Women's University;
| | - Hsin-I Wen
- Department of Bioorganization Research, Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences
| | - Tong Zhu
- Department of Bioorganization Research, Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences
| | - Kazumi Itoh
- Department of Mathematical and Physical Sciences, Faculty of Science, Japan Women's University
| | - Li Sheng
- Department of Bioorganization Research, Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences
| | - Kensuke Kurihara
- Department of Bioorganization Research, Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences; Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, National Institutes of Natural Sciences; Research Center for Complex Systems Biology, The University of Tokyo;
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42
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St. Clair JR, Wang Q, Li G, London E. Preparation and Physical Properties of Asymmetric Model Membrane Vesicles. SPRINGER SERIES IN BIOPHYSICS 2017. [DOI: 10.1007/978-981-10-6244-5_1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Lu L, Doak WJ, Schertzer JW, Chiarot PR. Membrane mechanical properties of synthetic asymmetric phospholipid vesicles. SOFT MATTER 2016; 12:7521-7528. [PMID: 27722472 PMCID: PMC5139623 DOI: 10.1039/c6sm01349j] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Synthetic lipid vesicles have served as important model systems to study cellular membrane biology. Research has shown that the mechanical properties of bilayer membranes significantly affects their biological behavior. The properties of a lipid bilayer are governed by lipid acyl chain length, headgroup type, and the presence of membrane proteins. However, few studies have explored how membrane architecture, in particular trans-bilayer lipid asymmetry, influences membrane mechanical properties. In this study, we investigated the effects of lipid bilayer architecture (i.e. asymmetry) on the mechanical properties of biological membranes. This was achieved using a customized micropipette aspiration system and a novel microfluidic technique previously developed by our team for building asymmetric phospholipid vesicles with tailored bilayer architecture. We found that the bending modulus and area expansion modulus of the synthetic asymmetric bilayers were up to 50% larger than the values acquired for symmetric bilayers. This was caused by the dissimilar lipid distribution in each leaflet of the bilayer for the asymmetric membrane. To the best of our knowledge, this is the first report on the impact of trans-bilayer asymmetry on the area expansion modulus of synthetic bilayer membranes. Since the mechanical properties of bilayer membranes play an important role in numerous cellular processes, these results have significant implications for membrane biology studies.
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Affiliation(s)
- Li Lu
- Department of Mechanical Engineering, State University of New York at Binghamton, Binghamton, NY, USA. and Binghamton Biofilm Research Center, State University of New York at Binghamton, Binghamton, NY, USA
| | - William J Doak
- Department of Mechanical Engineering, State University of New York at Binghamton, Binghamton, NY, USA.
| | - Jeffrey W Schertzer
- Binghamton Biofilm Research Center, State University of New York at Binghamton, Binghamton, NY, USA and Department of Biological Sciences, State University of New York at Binghamton, Binghamton, NY, USA
| | - Paul R Chiarot
- Department of Mechanical Engineering, State University of New York at Binghamton, Binghamton, NY, USA. and Binghamton Biofilm Research Center, State University of New York at Binghamton, Binghamton, NY, USA
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44
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Heberle FA, Marquardt D, Doktorova M, Geier B, Standaert RF, Heftberger P, Kollmitzer B, Nickels JD, Dick R, Feigenson GW, Katsaras J, London E, Pabst G. Subnanometer Structure of an Asymmetric Model Membrane: Interleaflet Coupling Influences Domain Properties. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:5195-200. [PMID: 27128636 PMCID: PMC4910133 DOI: 10.1021/acs.langmuir.5b04562] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Cell membranes possess a complex three-dimensional architecture, including nonrandom lipid lateral organization within the plane of a bilayer leaflet, and compositional asymmetry between the two leaflets. As a result, delineating the membrane structure-function relationship has been a highly challenging task. Even in simplified model systems, the interactions between bilayer leaflets are poorly understood, due in part to the difficulty of preparing asymmetric model membranes that are free from the effects of residual organic solvent or osmotic stress. To address these problems, we have modified a technique for preparing asymmetric large unilamellar vesicles (aLUVs) via cyclodextrin-mediated lipid exchange in order to produce tensionless, solvent-free aLUVs suitable for a range of biophysical studies. Leaflet composition and structure were characterized using isotopic labeling strategies, which allowed us to avoid the use of bulky labels. NMR and gas chromatography provided precise quantification of the extent of lipid exchange and bilayer asymmetry, while small-angle neutron scattering (SANS) was used to resolve bilayer structural features with subnanometer resolution. Isotopically asymmetric POPC vesicles were found to have the same bilayer thickness and area per lipid as symmetric POPC vesicles, demonstrating that the modified exchange protocol preserves native bilayer structure. Partial exchange of DPPC into the outer leaflet of POPC vesicles produced chemically asymmetric vesicles with a gel/fluid phase-separated outer leaflet and a uniform, POPC-rich inner leaflet. SANS was able to separately resolve the thicknesses and areas per lipid of coexisting domains, revealing reduced lipid packing density of the outer leaflet DPPC-rich phase compared to typical gel phases. Our finding that a disordered inner leaflet can partially fluidize ordered outer leaflet domains indicates some degree of interleaflet coupling, and invites speculation on a role for bilayer asymmetry in modulating membrane lateral organization.
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Affiliation(s)
- Frederick A. Heberle
- Biology and Soft Matter Division, Joint Institute for
Neutron Sciences, and Biosciences Division, Oak Ridge National
Laboratory, Oak Ridge, Tennessee 37831, United States
- E-mail:
| | - Drew Marquardt
- Institute
of Molecular Biosciences, Biophysics Division, NAWI Graz, University of Graz, Graz 8010, Austria
- BioTechMed-Graz, Graz 8010, Austria
- E-mail:
| | - Milka Doktorova
- Tri-Institutional
PhD Program in Computational Biology and Medicine, Weill Cornell Medical College, New York, New York 10065, United States
- Department
of Molecular Biology and Genetics, Cornell
University, Ithaca, New York 14853, United
States
| | - Barbara Geier
- Institute
of Molecular Biosciences, Biophysics Division, NAWI Graz, University of Graz, Graz 8010, Austria
- BioTechMed-Graz, Graz 8010, Austria
| | - Robert F. Standaert
- Biology and Soft Matter Division, Joint Institute for
Neutron Sciences, and Biosciences Division, Oak Ridge National
Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Biochemistry and Cellular
& Molecular Biology, and Department of
Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Peter Heftberger
- Institute
of Molecular Biosciences, Biophysics Division, NAWI Graz, University of Graz, Graz 8010, Austria
- BioTechMed-Graz, Graz 8010, Austria
| | - Benjamin Kollmitzer
- Institute
of Molecular Biosciences, Biophysics Division, NAWI Graz, University of Graz, Graz 8010, Austria
- BioTechMed-Graz, Graz 8010, Austria
| | - Jonathan D. Nickels
- Biology and Soft Matter Division, Joint Institute for
Neutron Sciences, and Biosciences Division, Oak Ridge National
Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Robert
A. Dick
- Department
of Molecular Biology and Genetics, Cornell
University, Ithaca, New York 14853, United
States
| | - Gerald W. Feigenson
- Department
of Molecular Biology and Genetics, Cornell
University, Ithaca, New York 14853, United
States
| | - John Katsaras
- Biology and Soft Matter Division, Joint Institute for
Neutron Sciences, and Biosciences Division, Oak Ridge National
Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Biochemistry and Cellular
& Molecular Biology, and Department of
Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Erwin London
- Department
of Biochemistry and Cell Biology, Stony
Brook University, Stony Brook, New York 11794, United States
| | - Georg Pabst
- Institute
of Molecular Biosciences, Biophysics Division, NAWI Graz, University of Graz, Graz 8010, Austria
- BioTechMed-Graz, Graz 8010, Austria
- E-mail:
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45
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Capponi S, Freites JA, Tobias DJ, White SH. Interleaflet mixing and coupling in liquid-disordered phospholipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1858:354-62. [PMID: 26657692 DOI: 10.1016/j.bbamem.2015.11.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 11/03/2015] [Accepted: 11/21/2015] [Indexed: 01/02/2023]
Abstract
Organized as bilayers, phospholipids are the fundamental building blocks of cellular membranes and determine many of their biological functions. Interactions between the two leaflets of the bilayer (interleaflet coupling) have been implicated in the passage of information through membranes. However, physically, the meaning of interleaflet coupling is ill defined and lacks a structural basis. Using all-atom molecular dynamics simulations of fluid phospholipid bilayers of five different lipids with differing degrees of acyl-chain asymmetry, we have examined interleaflet mixing to gain insights into coupling. Reasoning that the transbilayer distribution of terminal methyl groups is an appropriate measure of interleaflet mixing, we calculated the transbilayer distributions of the acyl chain terminal methyl groups for five lipids: dioleoylphosphatidylcholine (DOPC), palmitoyloleoylphosphatidylcholine (POPC), stearoyloleoylphosphatidylcholine (SOPC), oleoylmyristoylphosphatidylcholine (OMPC), and dimyristoylphosphatidylcholine (DMPC). We observed in all cases very strong mixing across the bilayer midplane that diminished somewhat with increasing acyl-chain ordering defined by methylene order parameters. A hallmark of the interleaflet coupling idea is complementarity, which postulates that lipids with short alkyl chains in one leaflet will preferentially associate with lipids with long alkyl chains in the other leaflet. Our results suggest a much more complicated picture for thermally disordered bilayers that we call distributed complementarity, as measured by the difference in the peak positions of the sn-1 and sn-2 methyl distributions in the same leaflet.
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Affiliation(s)
- Sara Capponi
- Department of Physiology and Biophysics and Center for Biomembrane Systems, University of California at Irvine, Irvine, CA 92697, USA
| | - J Alfredo Freites
- Department of Chemistry and Center for Biomembrane Systems, University of California at Irvine, Irvine, CA 92697, USA
| | - Douglas J Tobias
- Department of Chemistry and Center for Biomembrane Systems, University of California at Irvine, Irvine, CA 92697, USA
| | - Stephen H White
- Department of Physiology and Biophysics and Center for Biomembrane Systems, University of California at Irvine, Irvine, CA 92697, USA.
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46
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Hood RR, DeVoe DL. High-Throughput Continuous Flow Production of Nanoscale Liposomes by Microfluidic Vertical Flow Focusing. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:5790-5799. [PMID: 26395346 DOI: 10.1002/smll.201501345] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/04/2015] [Indexed: 06/05/2023]
Abstract
Liposomes represent a leading class of nanoparticles for drug delivery. While a variety of techniques for liposome synthesis have been reported that take advantage of microfluidic flow elements to achieve precise control over the size and polydispersity of nanoscale liposomes, with important implications for nanomedicine applications, these methods suffer from extremely limited throughput, making them impractical for large-scale nanoparticle synthesis. High aspect ratio microfluidic vertical flow focusing is investigated here as a new approach to overcoming the throughput limits of established microfluidic nanoparticle synthesis techniques. Here the vertical flow focusing technique is utilized to generate populations of small, unilamellar, and nearly monodisperse liposomal nanoparticles with exceptionally high production rates and remarkable sample homogeneity. By leveraging this platform, liposomes with modal diameters ranging from 80 to 200 nm are prepared at production rates as high as 1.6 mg min(-1) in a simple flow-through process.
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Affiliation(s)
- Renee R Hood
- Department of Mechanical Engineering, 3126 Glenn L Martin Hall, University of Maryland, College Park, College Park, MD, 20742, USA
| | - Don L DeVoe
- Department of Mechanical Engineering, 3126 Glenn L Martin Hall, University of Maryland, College Park, College Park, MD, 20742, USA
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47
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Nickels JD, Smith JC, Cheng X. Lateral organization, bilayer asymmetry, and inter-leaflet coupling of biological membranes. Chem Phys Lipids 2015; 192:87-99. [DOI: 10.1016/j.chemphyslip.2015.07.012] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 07/20/2015] [Accepted: 07/25/2015] [Indexed: 11/28/2022]
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48
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Chiba M, Miyazaki M, Ishiwata S. Quantitative analysis of the lamellarity of giant liposomes prepared by the inverted emulsion method. Biophys J 2015; 107:346-354. [PMID: 25028876 DOI: 10.1016/j.bpj.2014.05.039] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 05/29/2014] [Indexed: 11/26/2022] Open
Abstract
The inverted emulsion method is used to prepare giant liposomes by pushing water-in-oil droplets through the oil/water interface into an aqueous medium. Due to the high encapsulation efficiency of proteins under physiological conditions and the simplicity of the protocol, it has been widely used to prepare various cell models. However, the lamellarity of liposomes prepared by this method has not been evaluated quantitatively. Here, we prepared liposomes that were partially stained with a fluorescent dye, and analyzed their fluorescence intensity under an epifluorescence microscope. The fluorescence intensities of the membranes of individual liposomes were plotted against their diameter. The plots showed discrete distributions, which were classified into several groups. The group with the lowest fluorescence intensity was determined to be unilamellar by monitoring the exchangeability of the inner and the outer solutions of the liposomes in the presence of the pore-forming toxin α-hemolysin. Increasing the lipid concentration dissolved in oil increased the number of liposomes ∼100 times. However, almost all the liposomes were unilamellar even at saturating lipid concentrations. We also investigated the effects of lipid composition and liposome content, such as highly concentrated actin filaments and Xenopus egg extracts, on the lamellarity of the liposomes. Remarkably, over 90% of the liposomes were unilamellar under all conditions examined. We conclude that the inverted emulsion method can be used to efficiently prepare giant unilamellar liposomes and is useful for designing cell models.
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Affiliation(s)
- Masataka Chiba
- Department of Physics, Faculty of Science and Engineering, Waseda University, Tokyo, Japan
| | - Makito Miyazaki
- Department of Physics, Faculty of Science and Engineering, Waseda University, Tokyo, Japan
| | - Shin'ichi Ishiwata
- Department of Physics, Faculty of Science and Engineering, Waseda University, Tokyo, Japan; Waseda Bioscience Research Institute in Singapore (WABIOS), Singapore, Singapore.
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Morita M, Onoe H, Yanagisawa M, Ito H, Ichikawa M, Fujiwara K, Saito H, Takinoue M. Droplet-Shooting and Size-Filtration (DSSF) Method for Synthesis of Cell-Sized Liposomes with Controlled Lipid Compositions. Chembiochem 2015. [DOI: 10.1002/cbic.201500354] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Masamune Morita
- Department of Computational Intelligence and Systems Science; Tokyo Institute of Technology; Kanagawa 226-8502 Japan
| | - Hiroaki Onoe
- Department of Mechanical Engineering; Keio University; Kanagawa 223-8522 Japan
| | - Miho Yanagisawa
- Department of Applied Physics; Tokyo University of Agriculture and Technology; Tokyo 184-8588 Japan
| | - Hiroaki Ito
- Department of Physics; Kyoto University; Kyoto 606-8502 Japan
| | | | - Kei Fujiwara
- Department of Bioscience and Informatics; Keio University; Kanagawa 223-8522 Japan
| | - Hirohide Saito
- Center for iPS Cell Research and Application (CiRA); Kyoto University; Kyoto 606-8507 Japan
| | - Masahiro Takinoue
- Department of Computational Intelligence and Systems Science; Tokyo Institute of Technology; Kanagawa 226-8502 Japan
- PRESTO; Japan Science and Technology Agency; Saitama 332-0012 Japan
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50
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Ho KKY, Murray VL, Liu AP. Engineering artificial cells by combining HeLa-based cell-free expression and ultrathin double emulsion template. Methods Cell Biol 2015; 128:303-18. [PMID: 25997354 DOI: 10.1016/bs.mcb.2015.01.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Generation of artificial cells provides the bridge needed to cover the gap between studying the complexity of biological processes in whole cells and studying these same processes in an in vitro reconstituted system. Artificial cells are defined as the encapsulation of biologically active material in a biological or synthetic membrane. Here, we describe a robust and general method to produce artificial cells for the purpose of mimicking one or more behaviors of a cell. A microfluidic double emulsion system is used to encapsulate a mammalian cell-free expression system that is able to express membrane proteins into the bilayer or soluble proteins inside the vesicles. The development of a robust platform that allows the assembly of artificial cells is valuable in understanding subcellular functions and emergent behaviors in a more cell-like environment as well as for creating novel signaling pathways to achieve specific cellular behaviors.
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Affiliation(s)
- Kenneth K Y Ho
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Victoria L Murray
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Allen P Liu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA; Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI, USA; Biophysics Program, University of Michigan, Ann Arbor, MI, USA
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