1
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Petrikat RI, Hornbogen J, Schmitt MJP, Resmann E, Wiedemann C, Dilmen NI, Schneider H, Pick AM, Riehn C, Diller R, Becker S. A Photoswitchable Metallocycle Based on Azobenzene: Synthesis, Characterization, and Ultrafast Dynamics. Chemistry 2024; 30:e202400205. [PMID: 38526989 DOI: 10.1002/chem.202400205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 03/25/2024] [Accepted: 03/25/2024] [Indexed: 03/27/2024]
Abstract
The novel photoswitchable ligand 3,3'-Azobenz(metPA)2 (1) is used to prepare a [Cu2(1)2](BF4)2 metallocycle (2), whose photoisomerization was characterized using static and time-resolved spectroscopic methods. Optical studies demonstrate the highly quantitative and reproducible photoinduced cyclic E/Z switching without decay of the complex. Accordingly and best to our knowledge, [Cu2(1)2](BF4)2 constitutes the first reversibly photoswitchable (3d)-metallocycle based on azobenzene. The photoinduced multiexponential dynamics in the sub-picosecond to few picosecond time domain of 1 and 2 have been assessed. These ultrafast dynamics as well as the yield of the respective photostationary state (PSSZ = 65 %) resemble the behavior of archetypical azobenzene. Also, the innovative pump-probe laser technique of gas phase transient photodissociation (τ-PD) in a mass spectrometric ion trap was used to determine the intrinsic relaxation dynamics for the isolated complex. These results are consistent with the results from femtosecond UV/Vis transient absorption (fs-TA) in solution, emphasizing the azobenzene-like dynamics of 2. This unique combination of fs-TA and τ-PD enables valuable insights into the prevailing interplay of dynamics and solvation. Both analyses (in solution and gas phase) and quantum chemical calculations reveal a negligible effect of the metal coordination on the switching mechanism and electronic pathway, which suggests a non-cooperative isomerization process.
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Affiliation(s)
- Raphael I Petrikat
- Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany
| | - Justin Hornbogen
- Fachbereich Physik, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 46, 67663, Kaiserslautern, Germany
| | - Marcel J P Schmitt
- Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany
| | - Emma Resmann
- Fachbereich Physik, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 46, 67663, Kaiserslautern, Germany
| | - Christina Wiedemann
- Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany
| | - Nesrin I Dilmen
- Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany
| | - Heinrich Schneider
- Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany
| | - Annika M Pick
- Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany
| | - Christoph Riehn
- Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany
- Research Center OPTIMAS, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 46, 67663, Kaiserslautern, Germany
| | - Rolf Diller
- Fachbereich Physik, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 46, 67663, Kaiserslautern, Germany
| | - Sabine Becker
- Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany
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2
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Hrebonkin A, Afonin S, Nikitjuka A, Borysov OV, Leitis G, Babii O, Koniev S, Lorig T, Grage SL, Nick P, Ulrich AS, Jirgensons A, Komarov IV. Spiropyran-Based Photoisomerizable α-Amino Acid for Membrane-Active Peptide Modification. Chemistry 2024; 30:e202400066. [PMID: 38366887 DOI: 10.1002/chem.202400066] [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: 01/08/2024] [Revised: 02/11/2024] [Accepted: 02/12/2024] [Indexed: 02/18/2024]
Abstract
Photoisomerizable peptides are promising drug candidates in photopharmacology. While azobenzene- and diarylethene-containing photoisomerizable peptides have already demonstrated their potential in this regard, reports on the use of spiropyrans to photoregulate bioactive peptides are still scarce. This work focuses on the design and synthesis of a spiropyran-derived amino acid, (S)-2-amino-3-(6'-methoxy-1',3',3'-trimethylspiro-[2H-1-benzopyran-2,2'-indolin-6-yl])propanoic acid, which is suitable for the preparation of photoisomerizable peptides. The utility of this amino acid is demonstrated by incorporating it into the backbone of BP100, a known membrane-active peptide, and by examining the photoregulation of the membrane perturbation by the spiropyran-containing peptides. The toxicity of the peptides (against the plant cell line BY-2), their bacteriotoxicity (E. coli), and actin-auxin oscillator modulation ability were shown to be significantly dependent on the photoisomeric state of the spiropyran unit.
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Affiliation(s)
- Andrii Hrebonkin
- Karlsruhe Institute of Technology, POB 3640, 76021, Karlsruhe, Germany
- Enamine, Vul. Winstona Churchilla 78, 02094, Kyiv, Ukraine
| | - Sergii Afonin
- Karlsruhe Institute of Technology, POB 3640, 76021, Karlsruhe, Germany
| | - Anna Nikitjuka
- Enamine, Vul. Winstona Churchilla 78, 02094, Kyiv, Ukraine
- Latvian Institute of Organic Synthesis, Aizkraukles iela 21, 1006, Riga, Latvia
| | - Oleksandr V Borysov
- Enamine, Vul. Winstona Churchilla 78, 02094, Kyiv, Ukraine
- Latvian Institute of Organic Synthesis, Aizkraukles iela 21, 1006, Riga, Latvia
| | - Gundars Leitis
- Enamine, Vul. Winstona Churchilla 78, 02094, Kyiv, Ukraine
- Latvian Institute of Organic Synthesis, Aizkraukles iela 21, 1006, Riga, Latvia
| | - Oleg Babii
- Karlsruhe Institute of Technology, POB 3640, 76021, Karlsruhe, Germany
| | - Serhii Koniev
- Enamine, Vul. Winstona Churchilla 78, 02094, Kyiv, Ukraine
- Taras Shevchenko National University of Kyiv, Vul. Volodymyrska 60, 01601, Kyiv, Ukraine
| | - Theo Lorig
- Karlsruhe Institute of Technology, POB 3640, 76021, Karlsruhe, Germany
| | - Stephan L Grage
- Karlsruhe Institute of Technology, POB 3640, 76021, Karlsruhe, Germany
| | - Peter Nick
- Karlsruhe Institute of Technology, POB 3640, 76021, Karlsruhe, Germany
| | - Anne S Ulrich
- Karlsruhe Institute of Technology, POB 3640, 76021, Karlsruhe, Germany
| | - Aigars Jirgensons
- Latvian Institute of Organic Synthesis, Aizkraukles iela 21, 1006, Riga, Latvia
| | - Igor V Komarov
- Enamine, Vul. Winstona Churchilla 78, 02094, Kyiv, Ukraine
- Taras Shevchenko National University of Kyiv, Vul. Volodymyrska 60, 01601, Kyiv, Ukraine
- Lumobiotics, Auerstraße 2, 76227, Karlsruhe., Germany
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3
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Qutbuddin Y, Guinart A, Gavrilović S, Al Nahas K, Feringa BL, Schwille P. Light-Activated Synthetic Rotary Motors in Lipid Membranes Induce Shape Changes Through Membrane Expansion. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2311176. [PMID: 38215457 DOI: 10.1002/adma.202311176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/16/2023] [Indexed: 01/14/2024]
Abstract
Membranes are the key structures to separate and spatially organize cellular systems. Their rich dynamics and transformations during the cell cycle are orchestrated by specific membrane-targeted molecular machineries, many of which operate through energy dissipation. Likewise, man-made light-activated molecular rotary motors have previously shown drastic effects on cellular systems, but their physical roles on and within lipid membranes remain largely unexplored. Here, the impact of rotary motors on well-defined biological membranes is systematically investigated. Notably, dramatic mechanical transformations are observed in these systems upon motor irradiation, indicative of motor-induced membrane expansion. The influence of several factors on this phenomenon is systematically explored, such as motor concentration and membrane composition., Membrane fluidity is found to play a crucial role in motor-induced deformations, while only minor contributions from local heating and singlet oxygen generation are observed. Most remarkably, the membrane area expansion under the influence of the motors continues as long as irradiation is maintained, and the system stays out-of-equilibrium. Overall, this research contributes to a comprehensive understanding of molecular motors interacting with biological membranes, elucidating the multifaceted factors that govern membrane responses and shape transitions in the presence of these remarkable molecular machines, thereby supporting their future applications in chemical biology.
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Affiliation(s)
- Yusuf Qutbuddin
- Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry, 82152, Martinsried, Germany
| | - Ainoa Guinart
- Stratingh Institute for Chemistry, University of Groningen, Groningen, 9747 AG, The Netherlands
| | - Svetozar Gavrilović
- Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry, 82152, Martinsried, Germany
| | - Kareem Al Nahas
- Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry, 82152, Martinsried, Germany
| | - Ben L Feringa
- Stratingh Institute for Chemistry, University of Groningen, Groningen, 9747 AG, The Netherlands
| | - Petra Schwille
- Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry, 82152, Martinsried, Germany
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Guo J, Wang S, Yu Z, Heng X, Zhou N, Chen G. Well-Defined Oligo(azobenzene- graft-mannose): Photostimuli Supramolecular Self-Assembly and Immune Effect Regulation. ACS Macro Lett 2024; 13:273-279. [PMID: 38345474 DOI: 10.1021/acsmacrolett.3c00663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
The immune system can recognize and respond to pathogens of various shapes. Synthetic materials that can change their shape have the potential to be used in vaccines and immune regulation. The ability of supramolecular assemblies to undergo reversible transformations in response to environmental stimuli allows for dynamic changes in their shapes and functionalities. A meticulously designed oligo(azobenzene-graft-mannose) was synthesized using a stepwise iterative method and "click" chemistry. This involved integrating hydrophobic and photoresponsive azobenzene units with hydrophilic and bioactive mannose units. The resulting oligomer, with its precise structure, displayed versatile assembly morphologies and chiralities that were responsive to light. These varying assembly morphologies demonstrated distinct capabilities in terms of inhibiting the proliferation of cancer cells and stimulating the maturation of dendritic cells. These discoveries contribute to the theoretical comprehension and advancement of photoswitchable bioactive materials.
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Affiliation(s)
- Jiangping Guo
- Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou 215006, P. R. China
| | - Shuyuan Wang
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Zhihong Yu
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Xingyu Heng
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Nianchen Zhou
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
| | - Gaojian Chen
- Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou 215006, P. R. China
- State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
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5
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Zhang JR, Mo Y, Fang W, Yuan YX, Yao JL, Wu JH. Insight into Multiphase Interlayer Molecular Packing and Stepwise Phase Transition in 4-(Phenylazo)benzoate Anion-Intercalated Layered Zinc Hydroxide. Inorg Chem 2024; 63:3692-3701. [PMID: 38340058 DOI: 10.1021/acs.inorgchem.3c03650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
The properties of layered intercalation hybrids are closely related to interlayer molecular packing. To develop functional intercalation hybrids, it is essential to gain deep insights into interlayer molecular packing. This work reports a new comprehensive insight into the controllable multiphase interlayer molecular packing in 4-(phenylazo)benzoate anion-intercalated layered zinc hydroxide (LZH-4-PAB intercalation hybrids). The new insight breaks up the general understanding that the interlayer molecular packing of anions is usually single-phase, lacking diversity and controllability. Furthermore, it uncovers an interesting stepwise rather than the generally expected continuous phase transition of the interlayer molecular packing. The intercalated 4-PAB anions initially organize into the horizontal monolayer packing (θ = 0°, Phase I), which stepwise transforms to the tilted interdigitated antiparallel bilayer packing (θ ≈ 50°, Phase II) along with an increased intercalation loading and eventually to the vertical interdigitated antiparallel bilayer packing (θ = 90°, Phase III). The LZH-4-PAB hybrids exhibited a greatly enhanced interlayer molecular packing-dependent UV-vis absorption. This study provides helpful guidance for developing property-tailored intercalation hybrids. It may attract new interest in more layered intercalation hybrids. New and rich intercalation chemistry might be discovered in more functional intercalation hybrids beyond the 4-PAB anion-intercalated layered zinc hydroxide.
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Affiliation(s)
- Jing-Ru Zhang
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 RenAi Road, Suzhou, Jiangsu 215123, China
| | - Yi Mo
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 RenAi Road, Suzhou, Jiangsu 215123, China
| | - Wei Fang
- Testing and Analysis Center, Soochow University, 199 RenAi Road, Suzhou, Jiangsu 215123, China
| | - Ya-Xian Yuan
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 RenAi Road, Suzhou, Jiangsu 215123, China
| | - Jian-Lin Yao
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 RenAi Road, Suzhou, Jiangsu 215123, China
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6
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Bassetto CAZ, Pfeffermann J, Yadav R, Strassgschwandtner S, Glasnov T, Bezanilla F, Pohl P. Photolipid excitation triggers depolarizing optocapacitive currents and action potentials. Nat Commun 2024; 15:1139. [PMID: 38326372 PMCID: PMC10850502 DOI: 10.1038/s41467-024-45403-y] [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: 08/23/2023] [Accepted: 01/22/2024] [Indexed: 02/09/2024] Open
Abstract
Optically-induced changes in membrane capacitance may regulate neuronal activity without requiring genetic modifications. Previously, they mainly relied on sudden temperature jumps due to light absorption by membrane-associated nanomaterials or water. Yet, nanomaterial targeting or the required high infrared light intensities obstruct broad applicability. Now, we propose a very versatile approach: photolipids (azobenzene-containing diacylglycerols) mediate light-triggered cellular de- or hyperpolarization. As planar bilayer experiments show, the respective currents emerge from millisecond-timescale changes in bilayer capacitance. UV light changes photolipid conformation, which awards embedding plasma membranes with increased capacitance and evokes depolarizing currents. They open voltage-gated sodium channels in cells, generating action potentials. Blue light reduces the area per photolipid, decreasing membrane capacitance and eliciting hyperpolarization. If present, mechanosensitive channels respond to the increased mechanical membrane tension, generating large depolarizing currents that elicit action potentials. Membrane self-insertion of administered photolipids and focused illumination allows cell excitation with high spatiotemporal control.
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Affiliation(s)
- Carlos A Z Bassetto
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA
| | - Juergen Pfeffermann
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020, Linz, Austria
| | - Rohit Yadav
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020, Linz, Austria
| | | | - Toma Glasnov
- Institute of Chemistry, Karl-Franzens-University, Graz, Austria
| | - Francisco Bezanilla
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA.
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile.
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020, Linz, Austria.
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Walden SL, Nguyen PHD, Li HK, Liu X, Le MTN, Xian Jun L, Barner-Kowollik C, Truong VX. Visible light-induced switching of soft matter materials properties based on thioindigo photoswitches. Nat Commun 2023; 14:8298. [PMID: 38097621 PMCID: PMC10721821 DOI: 10.1038/s41467-023-44128-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 11/30/2023] [Indexed: 12/17/2023] Open
Abstract
Thioindigos are visible light responsive photoswitches with excellent spatial control over the conformational change between their trans- and cis- isomers. However, they possess limited solubility in all conventional organic solvents and polymers, hindering their application in soft matter materials. Herein, we introduce a strategy for the covalent insertion of thioindigo units into polymer main chains, enabling thioindigos to function within crosslinked polymeric hydrogels. We overcome their solubility issue by developing a thioindigo bismethacrylate linker able to undergo radical initiated thiol-ene reaction for step-growth polymerization, generating indigo-containing polymers. The optimal wavelength for the reversible trans-/cis- isomerisation of thioindigo was elucidated by constructing a detailed photochemical action plot of their switching efficiencies at a wide range of monochromatic wavelengths. Critically, indigo-containing polymers display significant photoswitching of the materials' optical and physical properties in organic solvents and water. Furthermore, the photoswitching of thioindigo within crosslinked structures enables visible light induced modulation of the hydrogel stiffness. Both the thioindigo-containing hydrogels and photoswitching processes are non-toxic to cells, thus offering opportunities for advanced applications in soft matter materials and biology-related research.
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Affiliation(s)
- Sarah L Walden
- Centre for Materials Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia
| | - Phuong H D Nguyen
- Department of Pharmacology and Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Republic of Singapore
| | - Hao-Kai Li
- Fluorescence Research Group, Singapore University of Technology and Design, 8 Somapah Road, 487372, Singapore, Republic of Singapore
| | - Xiaogang Liu
- Fluorescence Research Group, Singapore University of Technology and Design, 8 Somapah Road, 487372, Singapore, Republic of Singapore
| | - Minh T N Le
- Department of Pharmacology and Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Republic of Singapore
| | - Loh Xian Jun
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Republic of Singapore.
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, Singapore, 627833, Republic of Singapore.
| | - Christopher Barner-Kowollik
- Centre for Materials Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia.
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia.
- Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany.
| | - Vinh X Truong
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia.
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Republic of Singapore.
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8
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Shendrik P, Golani G, Dharan R, Schwarz US, Sorkin R. Membrane Tension Inhibits Lipid Mixing by Increasing the Hemifusion Stalk Energy. ACS NANO 2023; 17:18942-18951. [PMID: 37669531 PMCID: PMC7615193 DOI: 10.1021/acsnano.3c04293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Accepted: 08/23/2023] [Indexed: 09/07/2023]
Abstract
Fusion of biological membranes is fundamental in various physiological events. The fusion process involves several intermediate stages with energy barriers that are tightly dependent on the mechanical and physical properties of the system, one of which is membrane tension. As previously established, the late stages of fusion, including hemifusion diaphragm and pore expansions, are favored by membrane tension. However, a current understanding of how the energy barrier of earlier fusion stages is affected by membrane tension is lacking. Here, we apply a newly developed experimental approach combining micropipette-aspirated giant unilamellar vesicles and optically trapped membrane-coated beads, revealing that membrane tension inhibits lipid mixing. We show that lipid mixing is 6 times slower under a tension of 0.12 mN/m compared with tension-free membranes. Furthermore, using continuum elastic theory, we calculate the dependence of the hemifusion stalk formation energy on membrane tension and intermembrane distance and find the increase in the corresponding energy barrier to be 1.6 kBT in our setting, which can explain the increase in lipid mixing time delay. Finally, we show that tension can be a significant factor in the stalk energy if the pre-fusion intermembrane distance is on the order of several nanometers, while for membranes that are tightly docked, tension has a negligible effect.
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Affiliation(s)
- Petr Shendrik
- School
of Chemistry, Raymond & Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
- Center
of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Gonen Golani
- Institute
for Theoretical Physics and BioQuant Center for Quantitative Biology, Heidelberg University, 69120, Heidelberg, Germany
| | - Raviv Dharan
- School
of Chemistry, Raymond & Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
- Center
of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Ulrich S. Schwarz
- Institute
for Theoretical Physics and BioQuant Center for Quantitative Biology, Heidelberg University, 69120, Heidelberg, Germany
| | - Raya Sorkin
- School
of Chemistry, Raymond & Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
- Center
of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, 6997801, Israel
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