1
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Schmidt R, Kiefer H, Dalgliesh R, Gradzielski M, Netz RR. Nanoscopic Interfacial Hydrogel Viscoelasticity Revealed from Comparison of Macroscopic and Microscopic Rheology. NANO LETTERS 2024; 24. [PMID: 38591912 PMCID: PMC11057034 DOI: 10.1021/acs.nanolett.3c04884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 04/02/2024] [Accepted: 04/03/2024] [Indexed: 04/10/2024]
Abstract
Deviations between macrorheological and particle-based microrheological measurements are often considered to be a nuisance and neglected. We study aqueous poly(ethylene oxide) (PEO) hydrogels for varying PEO concentrations and chain lengths that contain microscopic tracer particles and show that these deviations reveal the nanoscopic viscoelastic properties of the particle-hydrogel interface. Based on the transient Stokes equation, we first demonstrate that the deviations are not due to finite particle radius, compressibility, or surface-slip effects. Small-angle neutron scattering rules out hydrogel heterogeneities. Instead, we show that a generalized Stokes-Einstein relation, accounting for an interfacial shell around tracers with viscoelastic properties that deviate from bulk, consistently explains our macrorheological and microrheological measurements. The extracted shell diameter is comparable to the PEO end-to-end distance, indicating the importance of dangling chain ends. Our methodology reveals the nanoscopic interfacial rheology of hydrogels and is applicable to different kinds of viscoelastic fluids and particles.
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Affiliation(s)
- Robert
F. Schmidt
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, 10623 Berlin, Germany
| | - Henrik Kiefer
- Fachbereich
Physik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Robert Dalgliesh
- STFC, ISIS, Rutherford
Appleton
Laboratory, Chilton, Oxfordshire OX11 0QX, United Kingdom
| | - Michael Gradzielski
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, 10623 Berlin, Germany
| | - Roland R. Netz
- Fachbereich
Physik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
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2
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Racca NM, Dontu A, Riley K, Yolcu ES, Shirwan H, Coronel MM. Bending the Rules: Amplifying PD-L1 Immunoregulatory Function Through Flexible Polyethylene Glycol Synthetic Linkers. Tissue Eng Part A 2024; 30:299-313. [PMID: 38318841 DOI: 10.1089/ten.tea.2023.0274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024] Open
Abstract
Immune checkpoint signaling, such as programmed cell death protein-1 (PD-1), is a key target for immunotherapy due to its role in dampening immune responses. PD-1 signaling in T cells is regulated by complex physicochemical and mechanical cues. However, how these mechanical forces are integrated with biochemical responses remains poorly understood. Our previous work demonstrated that the use of an immobilizing polyethylene glycol (PEG) linker on synthetic microgels for the presentation of a chimeric form of PD-L1, SA-PD-L1, lead to local regulatory responses capable of abrogating allograft rejection in a model of cell-based transplantation. We herein provide evidence that enhanced immune regulating function can be obtained when presentation of SA-PD-L1 is achieved through a longer more flexible PEG chain. Presentation of SA-PD-L1 through a linker of high molecular weight, and thus longer length (10 kDa, 60 nm in length), led to enhance conversion of naive T cells into T regulatory cells (Tregs) in vitro. In addition, using a subcutaneous implant model and protein tethered through three different linker sizes (6, 30, and 60 nm) to the surface of PEG hydrogels, we demonstrated that longer linkers promoted PD-1 immunomodulatory role in vivo through three main functions: (1) augmenting immune cell recruitment at the transplant site; (2) promoting the accumulation of naive Tregs expressing migratory markers; and (3) dampening CD8+ cytolytic molecule production while augmenting expression of exhaustion phenotypes locally. Notably, accumulation of Treg cells at the implant site persisted for over 30 days postimplantation, an effect not observed when protein was presented with the shorter version of the linkers (6 and 30 nm). Collectively, these studies reveal a facile approach by which PD-L1 function can be modulated through external tuning of synthetic presenting linkers. Impact statement Recently, there has been a growing interest in immune checkpoint molecules as potential targets for tolerance induction, including programmed cell death protein-1 (PD-1). However, how the mechanics of ligand binding to PD-1 receptor affect downstream activation signaling pathways remains unresolved. By taking advantage of the effect of polyethylene glycol chain length on molecule kinetics in an aqueous solution, we herein show that PD-L1 function can be amplified by adjusting the length of the grafting linker. Our results uncover a potential facile mechanism that can be exploited to advance the role of immune checkpoint ligands, in particular PD-L1, in tolerance induction for immunosuppression-free cell-based therapies.
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Affiliation(s)
- Nicole M Racca
- Department of Biomedical Engineering and Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
- Elizabeth Caswell Diabetes Institute, University of Michigan, Ann Arbor, Michigan, USA
| | - Alexander Dontu
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kayle Riley
- Department of Biomedical Engineering and Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
- Elizabeth Caswell Diabetes Institute, University of Michigan, Ann Arbor, Michigan, USA
| | - Esma S Yolcu
- Department of Pediatrics and University of Missouri, Columbia, Missouri, USA
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, Missouri, USA
| | - Haval Shirwan
- Department of Pediatrics and University of Missouri, Columbia, Missouri, USA
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, Missouri, USA
- Associate Director, Immunomodulation and Regenerative Medicine Program, Ellis Fischel Cancer Center, Columbia, Missouri, USA
| | - María M Coronel
- Department of Biomedical Engineering and Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
- Elizabeth Caswell Diabetes Institute, University of Michigan, Ann Arbor, Michigan, USA
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3
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Zhang S, Zheng H, Miao X, Zhang G, Song Y, Kang X, Qian L. Surprising Nanomechanical and Conformational Transition of Neutral Polyacrylamide in Monovalent Saline Solutions. J Phys Chem B 2023; 127:10088-10096. [PMID: 37939001 DOI: 10.1021/acs.jpcb.3c06126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Polyacrylamide (PAM) is one of the most important water-soluble polymers that has been extensively applied in water treatment, drug delivery, and flexible electronic devices. The basic properties, e.g., microstructure, nanomechanics, and solubility, are deeply involved in the performance of PAM materials. Current research has paid more attention to the development and expansion of the macroscopic properties of PAM materials, and the study of the mechanism involved with the roles of water and ions on the properties of PAM is insufficient, especially for the behaviors of neutral amide side groups. In this study, single molecule force spectroscopy was combined with molecular dynamic (MD) simulations, atomic force microscope imaging, and dynamic light scattering to investigate the effects of monovalent ions on the nanomechanics and molecular conformations of neutral PAM (NPAM). These results show that the single-molecule elasticity and conformation of NPAM exhibit huge variation in different monovalent salt solutions. NPAM adopts an extended conformation in aqueous solutions of strong hydrated ion (acetate), while transforms into a collapse globule in the existence of weakly hydrated ion (SCN-). It is believed that the competition between intramolecular and intermolecular weak interactions plays a key role to adjust the molecular conformation and elasticity of NPAM. The competition can be largely influenced by the type of monovalent ions through hydration or a chaotropic effect. Methods utilized in this study provide a means to better understand the Hofmeister effect of ions on other macromolecules containing amide groups at the single-molecule level.
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Affiliation(s)
- Song Zhang
- Department of Food Science and Engineering, Moutai Institute, Renhuai 564502, Guizhou, P. R. China
| | - Huayan Zheng
- Department of Food Science and Engineering, Moutai Institute, Renhuai 564502, Guizhou, P. R. China
| | - Xiaohe Miao
- Instrumentation and Service Center for Physical Sciences, Westlake University, Hangzhou 310024, Zhejiang Province, China
| | - Guoqiang Zhang
- Department of Food Science and Engineering, Moutai Institute, Renhuai 564502, Guizhou, P. R. China
| | - Ya Song
- Department of Food Science and Engineering, Moutai Institute, Renhuai 564502, Guizhou, P. R. China
| | - Xiaomin Kang
- School of Mechanical Engineering, University of South China, Hengyang 421001, China
| | - Lu Qian
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, Guangdong, China
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4
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Truong HP, Koren G, Avinery R, Beck R, Saleh OA. Pincus blob elasticity in an intrinsically disordered protein. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2023; 46:100. [PMID: 37847354 DOI: 10.1140/epje/s10189-023-00360-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 09/29/2023] [Indexed: 10/18/2023]
Abstract
Understanding the dynamic structure of intrinsically disordered proteins (IDPs) is important to deciphering their biological functions. Here, we exploit precision entropic elasticity measurements to infer the conformational behavior of a model IDP construct formed from the disordered tail of the neurofilament low molecular weight protein. The IDP construct notably displays a low-force power-law elastic regime, consistent with the Pincus blob model, which allows direct extraction of the Flory exponent, [Formula: see text], from the force-extension relationship. We find [Formula: see text] increases with added denaturant, transitioning from a nearly ideal chain to a swollen chain in a manner quantitatively consistent with measurements of IDP dimensions from other experimental techniques. We suggest that measurements of entropic elasticity could be broadly useful in the study of IDP structure.
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Affiliation(s)
- Hoang P Truong
- Materials Department, University of California, Santa Barbara, USA
| | - Gil Koren
- The Raymond and Beverly Sackler School of Physics and Astronomy and The Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv, Israel
- The Center of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel
| | - Ram Avinery
- The Raymond and Beverly Sackler School of Physics and Astronomy and The Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv, Israel
- The Center of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel
| | - Roy Beck
- The Raymond and Beverly Sackler School of Physics and Astronomy and The Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv, Israel
- The Center of Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel
| | - Omar A Saleh
- Materials Department, University of California, Santa Barbara, USA.
- Biomolecular Sciences and Engineering Department, University of California, Santa Barbara, USA.
- Physics Department, University of California, Santa Barbara, USA.
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5
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Schmidt RF, Prévost S, Gradzielski M, Zemb T. Structure of microemulsions in the continuous phase channel. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2023; 46:76. [PMID: 37668863 PMCID: PMC10480248 DOI: 10.1140/epje/s10189-023-00337-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 08/24/2023] [Indexed: 09/06/2023]
Abstract
We have studied the microemulsion and lamellar phases of two of the most commonly described systems based on nonionic C12E5 and ionic AOT surfactants. We show that C12E5 is best described by the symmetric disordered open connected lamellar model (DOC-lamellar), contrary to the more commonly employed standard flexible model. In the case of AOT, the bicontinuous microemulsion structure is best described by the standard flexible model at high temperatures. Around room temperature, connected cylinders in a molten cubic crystal phase are the only description which corresponds to the data. In the lamellar phase, around one third of the available surface area is lost in fluctuations and defects. Comparing structurally predictive models with results from conductivity measurements show that salt adsorption in the hydrated ethoxy groups is dominant for C12E5 (nonionic). For AOT, our conductivity measurements clarify the role of tortuosity versus cation absorption.
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Affiliation(s)
- Robert Franz Schmidt
- Stranski-Laboratorium Für Physikalische Und Theoretische Chemie, Institut Für Chemie, Technische Universität Berlin, Straße Des 17. Juni 124, 10623, Berlin, Germany.
| | - Sylvain Prévost
- Institut Laue-Langevin, 71 Avenue Des Martyrs CS 20156, 38042, Grenoble Cedex 9, France
| | - Michael Gradzielski
- Stranski-Laboratorium Für Physikalische Und Theoretische Chemie, Institut Für Chemie, Technische Universität Berlin, Straße Des 17. Juni 124, 10623, Berlin, Germany
| | - Thomas Zemb
- UMR 5257 - CEA/CNRS/UM/ENSCM, Institut de Chimie Séparative de Marcoule, ICSM, 30207, Marcoule, France.
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6
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Blanco PM, Narambuena CF, Madurga S, Mas F, Garcés JL. Unusual Aspects of Charge Regulation in Flexible Weak Polyelectrolytes. Polymers (Basel) 2023; 15:2680. [PMID: 37376324 DOI: 10.3390/polym15122680] [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: 05/22/2023] [Revised: 06/07/2023] [Accepted: 06/10/2023] [Indexed: 06/29/2023] Open
Abstract
This article reviews the state of the art of the studies on charge regulation (CR) effects in flexible weak polyelectrolytes (FWPE). The characteristic of FWPE is the strong coupling of ionization and conformational degrees of freedom. After introducing the necessary fundamental concepts, some unconventional aspects of the the physical chemistry of FWPE are discussed. These aspects are: (i) the extension of statistical mechanics techniques to include ionization equilibria and, in particular, the use of the recently proposed Site Binding-Rotational Isomeric State (SBRIS) model, which allows the calculation of ionization and conformational properties on the same foot; (ii) the recent progresses in the inclusion of proton equilibria in computer simulations; (iii) the possibility of mechanically induced CR in the stretching of FWPE; (iv) the non-trivial adsorption of FWPE on ionized surfaces with the same charge sign as the PE (the so-called "wrong side" of the isoelectric point); (v) the influence of macromolecular crowding on CR.
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Affiliation(s)
- Pablo M Blanco
- Physical Chemistry Unit, Materials Science and Physical Chemistry Department & Research Institute of Theoretical and Computational Chemistry (IQTCUB), Barcelona University (UB), 08028 Barcelona, Catalonia, Spain
| | - Claudio F Narambuena
- Grupo de Bionanotecnologia y Sistemas Complejos, Infap-CONICET & Facultad Regional San Rafael, Universidad Tecnológica Nacional, San Rafael 5600, Argentina
| | - Sergio Madurga
- Physical Chemistry Unit, Materials Science and Physical Chemistry Department & Research Institute of Theoretical and Computational Chemistry (IQTCUB), Barcelona University (UB), 08028 Barcelona, Catalonia, Spain
| | - Francesc Mas
- Physical Chemistry Unit, Materials Science and Physical Chemistry Department & Research Institute of Theoretical and Computational Chemistry (IQTCUB), Barcelona University (UB), 08028 Barcelona, Catalonia, Spain
| | - Josep L Garcés
- Chemistry Department, Technical School of Agricultural Engineering & AGROTECNIO, Lleida University (UdL), 25003 Lleida, Catalonia, Spain
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7
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Gokulu IS, Banta S. Biotechnology applications of proteins functionalized with DNA oligonucleotides. Trends Biotechnol 2023; 41:575-585. [PMID: 36115723 DOI: 10.1016/j.tibtech.2022.08.004] [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: 07/11/2022] [Revised: 08/16/2022] [Accepted: 08/18/2022] [Indexed: 10/14/2022]
Abstract
The functionalization of proteins with DNA through the formation of covalent bonds enables a wide range of biotechnology advancements. For example, single-molecule analytical methods rely on bioconjugated DNA as elastic biolinkers for protein immobilization. Labeling proteins with DNA enables facile protein identification, as well as spatial and temporal organization and control of protein within DNA-protein networks. Bioconjugation reactions can target native, engineered, and non-canonical amino acids (NCAAs) within proteins. In addition, further protein engineering via the incorporation of peptide tags and self-labeling proteins can also be used for conjugation reactions. The selection of techniques will depend on application requirements such as yield, selectivity, conjugation position, potential for steric hindrance, cost, commercial availability, and potential impact on protein function.
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Affiliation(s)
- Ipek Simay Gokulu
- Department of Chemical Engineering, Columbia University, 500 West 120th Street, New York, NY 10027, USA
| | - Scott Banta
- Department of Chemical Engineering, Columbia University, 500 West 120th Street, New York, NY 10027, USA.
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8
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Kerkhoff Y, Azizi L, Mykuliak VV, Hytönen VP, Block S. Microfluidics-Based Force Spectroscopy Enables High-Throughput Force Experiments with Sub-Nanometer Resolution and Sub-Piconewton Sensitivity. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2206713. [PMID: 36631276 DOI: 10.1002/smll.202206713] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/23/2022] [Indexed: 06/17/2023]
Abstract
Several techniques have been established to quantify the mechanicals of single molecules. However, most of them show only limited capabilities of parallelizing the measurement by performing many individual measurements simultaneously. Herein, a microfluidics-based single-molecule force spectroscopy method, which achieves sub-nanometer spatial resolution and sub-piconewton sensitivity and is capable of simultaneously quantifying hundreds of single-molecule targets in parallel, is presented. It relies on a combination of total internal reflection microscopy and microfluidics, in which monodisperse fluorescent beads are immobilized on the bottom of a microfluidic channel by macromolecular linkers. Application of a flow generates a well-defined shear force acting on the beads, whereas the nanomechanical linker response is quantified based on the force-induced displacement of individual beads. To handle the high amount of data generated, a cluster analysis which is capable of a semi-automatic identification of measurement artifacts and molecular populations is implemented. The method is validated by probing the mechanical response polyethylene glycol linkers and binding strength of biotin-NeutrAvidin complexes. Two energy barriers (at 3 and 5.7 Å, respectively) in the biotin-NeutrAvidin interaction are resolved and the unfolding behavior of talin's rod domain R3 in the force range between 1 to ≈10 pN is probed.
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Affiliation(s)
- Yannic Kerkhoff
- Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Latifeh Azizi
- Faculty of Medicine and Health Technology, Tampere University, Arvo Ylpön katu 34, Tampere, FI-33520, Finland
| | - Vasyl V Mykuliak
- Faculty of Medicine and Health Technology, Tampere University, Arvo Ylpön katu 34, Tampere, FI-33520, Finland
| | - Vesa P Hytönen
- Faculty of Medicine and Health Technology, Tampere University, Arvo Ylpön katu 34, Tampere, FI-33520, Finland
- Fimlab Laboratories, Biokatu 4, Tampere, FI-33520, Finland
| | - Stephan Block
- Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
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9
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Bittermann MR, Morozova TI, Velandia SF, Mirzahossein E, Deblais A, Woutersen S, Bonn D. Surface-Mediated Molecular Transport of a Lipophilic Fluorescent Probe in Polydisperse Oil-in-Water Emulsions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:4207-4215. [PMID: 36919825 PMCID: PMC10061922 DOI: 10.1021/acs.langmuir.2c02597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/07/2023] [Indexed: 06/18/2023]
Abstract
Emulsions often act as carriers for water-insoluble solutes that are delivered to a specific target. The molecular transport of solutes in emulsions can be facilitated by surfactants and is often limited by diffusion through the continuous phase. We here investigate this transport on a molecular scale by using a lipophilic molecular rotor as a proxy for solutes. Using fluorescence lifetime microscopy we track the transport of these molecules from the continuous phase toward the dispersed phase in polydisperse oil-in-water emulsions. We show that this transport comprises two time scales, which vary significantly with droplet size and surfactant concentration, and, depending on the type of surfactant used, can be limited either by transport across the oil-water interface or by diffusion through the continuous phase. By studying the time-resolved fluorescence of the fluorophore, accompanied by molecular dynamics simulations, we demonstrate how the rate of transport observed on a macroscopic scale can be explained in terms of the local environment that the probe molecules are exposed to.
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Affiliation(s)
- Marius R. Bittermann
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | | | - Santiago F. Velandia
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Elham Mirzahossein
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Antoine Deblais
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Sander Woutersen
- Van
’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Daniel Bonn
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
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10
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Bao Y, Cui S. Single-Chain Inherent Elasticity of Macromolecules: From Concept to Applications. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:3527-3536. [PMID: 36848243 DOI: 10.1021/acs.langmuir.2c03234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
"The Tao begets the One. One begets all things of the world." These words of wisdom from Tao Te Ching are of great inspiration to scientists in polymer materials science and engineering: The "One" means an individual polymer chain while polymer materials consist of numerous chains. The understanding of the single-chain mechanics of polymers is crucial for the bottom-up rational design of polymer materials. With a backbone and side chains, a polymer chain is more complex than a small molecule. Moreover, an individual polymer chain is usually placed in a complicated environment (such as solvent, cosolute, and solid surface), which significantly affects the behaviors of the chain. With all these factors, it is hard to fully understand the elastic behaviors of polymers. Herein, we will first introduce the concept of the single-chain inherent elasticity of polymers, which is a fundamental property determined by the polymer backbone. Then, the applications of inherent elasticity in quantifying the effects of side chains and surrounding environment will be summarized. Finally, the challenges in related fields at present and potential research directions in the future will be discussed.
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Affiliation(s)
- Yu Bao
- School of Chemistry, Key Lab of Advanced Technologies of Materials (Ministry of Education), Southwest Jiaotong University, Chengdu 610031, China
| | - Shuxun Cui
- School of Chemistry, Key Lab of Advanced Technologies of Materials (Ministry of Education), Southwest Jiaotong University, Chengdu 610031, China
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11
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Walter M, Linsler D, König T, Gäbert C, Reinicke S, Moseler M, Mayrhofer L. Mechanochemical Activation of Anthracene [4+4] Cycloadducts. J Phys Chem Lett 2023; 14:1445-1451. [PMID: 36734822 DOI: 10.1021/acs.jpclett.2c03493] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Controlled formation and breaking of weak chemical bonds is a versatile method for modifying the properties of materials. Anthracene [4+4] cycloadducts are a prime example that can be formed by light and opened by external forces. We address the theoretical description of mechanochemistry of these cycloadducts, where the standard constraint geometry simulates forces approach fails due to the lack of consideration of temperature. Explicit inclusion of external forces reveals the corresponding transition barriers that are clearly dominated by rupture of the [4+4] inter-anthracene bonds. Other bonds come into play at extremely large forces only, which cannot be expected to be reached under ambient conditions. The theoretical results are in line with the experimental rheology of [4+4]-linked anthracene polymers, which indicates reversible re-formation of [4+4] cycloaddition bonds with ultraviolet light after mechanochemical bond breaking due to applied shear stress.
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Affiliation(s)
- Michael Walter
- Fraunhofer IWM, MikroTribologie Centrum μTC, 76131Karlsruhe, Germany
- FIT Freiburg Centre for Interactive Materials and Bioinspired Technologies, University of Freiburg, 79085Freiburg, Germany
- Cluster of Excellence livMatS@FIT, 79110Freiburg, Germany
| | - Dominic Linsler
- Fraunhofer IWM, MikroTribologie Centrum μTC, 76131Karlsruhe, Germany
| | - Tobias König
- Fraunhofer IWM, MikroTribologie Centrum μTC, 76131Karlsruhe, Germany
| | | | | | - Michael Moseler
- Fraunhofer IWM, MikroTribologie Centrum μTC, 76131Karlsruhe, Germany
- Cluster of Excellence livMatS@FIT, 79110Freiburg, Germany
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12
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Zhang S, Li W, Luan J, Srivastava A, Carnevale V, Klein ML, Sun J, Wang D, Teora SP, Rijpkema SJ, Meeldijk JD, Wilson DA. Adaptive insertion of a hydrophobic anchor into a poly(ethylene glycol) host for programmable surface functionalization. Nat Chem 2023; 15:240-247. [PMID: 36411361 PMCID: PMC9899690 DOI: 10.1038/s41557-022-01090-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 10/17/2022] [Indexed: 11/22/2022]
Abstract
Covalent and non-covalent molecular binding are two strategies to tailor surface properties and functions. However, the lack of responsiveness and requirement for specific binding groups makes spatiotemporal control challenging. Here, we report the adaptive insertion of a hydrophobic anchor into a poly(ethylene glycol) (PEG) host as a non-covalent binding strategy for surface functionalization. By using polycyclic aromatic hydrocarbons as the hydrophobic anchor, hydrophilic charged and non-charged functional modules were spontaneously loaded onto PEG corona in 2 min without the assistance of any catalysts and binding groups. The thermodynamically favourable insertion of the hydrophobic anchor can be reversed by pulling the functional module, enabling programmable surface functionalization. We anticipate that the adaptive molecular recognition between the hydrophobic anchor and the PEG host will challenge the hydrophilic understanding of PEG and enhance the progress in nanomedicine, advanced materials and nanotechnology.
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Affiliation(s)
- Shaohua Zhang
- grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, the Netherlands
| | - Wei Li
- grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, the Netherlands
| | - Jiabin Luan
- grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, the Netherlands
| | - Abhinav Srivastava
- grid.264727.20000 0001 2248 3398Institute for Genomics and Evolutionary Medicine (iGEM) and Department of Biology, Temple University, Philadelphia, PA USA ,grid.264727.20000 0001 2248 3398Institute for Computational Molecular Science, Temple University, Philadelphia, PA USA
| | - Vincenzo Carnevale
- grid.264727.20000 0001 2248 3398Institute for Genomics and Evolutionary Medicine (iGEM) and Department of Biology, Temple University, Philadelphia, PA USA ,grid.264727.20000 0001 2248 3398Institute for Computational Molecular Science, Temple University, Philadelphia, PA USA
| | - Michael L. Klein
- grid.264727.20000 0001 2248 3398Institute for Computational Molecular Science, Temple University, Philadelphia, PA USA
| | - Jiawei Sun
- grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, the Netherlands
| | - Danni Wang
- grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, the Netherlands
| | - Serena P. Teora
- grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, the Netherlands
| | - Sjoerd J. Rijpkema
- grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, the Netherlands
| | - Johannes D. Meeldijk
- grid.5477.10000000120346234Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Utrecht, the Netherlands
| | - Daniela A. Wilson
- grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, the Netherlands
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13
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Khodayeki S, Maftuhin W, Walter M. Force Dependent Barriers from Analytic Potentials within Elastic Environments. Chemphyschem 2022; 23:e202200237. [PMID: 35703590 DOI: 10.1002/cphc.202200237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/14/2022] [Indexed: 01/07/2023]
Abstract
Bond rupture under the action of external forces is usually induced by temperature fluctuations, where the key quantity is the force dependent barrier that needs to be overcome. Using analytic potentials we find that these barriers are fully determined by the dissociation energy and the maximal force the potential can withstand. The barrier shows a simple dependence on these two quantities that allows for a re-interpretation of the Eyring-Zhurkov-Bell length Δ x ‡ and the expressions in theories going beyond that. It is shown that solely elastic environments do not change this barrier in contrast to the predictions of constraint geometry simulate external force (COGEF) strategies. The findings are confirmed by explicit calculations of bond rupture in a polydimethylsiloxane model.
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Affiliation(s)
- Samaneh Khodayeki
- Freiburger Institut für Interaktive Materialien und Bioinspirierte Technologien, Georges-Köhler-Allee 105, 79110, Freiburg, Germany.,Physikalisches Institut, Universität Freiburg, Herrmann-Herder-Straße 3, 79104, Freiburg, Germany
| | - Wafa Maftuhin
- Freiburger Institut für Interaktive Materialien und Bioinspirierte Technologien, Georges-Köhler-Allee 105, 79110, Freiburg, Germany.,Physikalisches Institut, Universität Freiburg, Herrmann-Herder-Straße 3, 79104, Freiburg, Germany
| | - Michael Walter
- Freiburger Institut für Interaktive Materialien und Bioinspirierte Technologien, Georges-Köhler-Allee 105, 79110, Freiburg, Germany.,Physikalisches Institut, Universität Freiburg, Herrmann-Herder-Straße 3, 79104, Freiburg, Germany.,Cluster of Excellence livMatS@FIT, Freiburg, Germany.,Fraunhofer Institut für Werkstoffmechanik, Wöhlerstraße 11, 79108, Freiburg, Germany
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14
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Loche P, Scalfi L, Ali Amu M, Schullian O, Bonthuis D, Rotenberg B, Netz RR. Effects of surface rigidity and metallicity on dielectric properties and ion interactions at aqueous hydrophobic interfaces. J Chem Phys 2022; 157:094707. [DOI: 10.1063/5.0101509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Using classical molecular dynamics simulations we investigate the dielectric properties at interfaces of water with graphene, graphite, hexane and water vapor. For graphite we compare metallic and non-metallic versions. At the vapor-liquid water and hexane-water interfaces the laterally averaged dielectric profiles are significantly broadened due to interfacial roughness and only slightly anisotropic. In contrast, at the rigid graphene surface the dielectric profiles are strongly anisotropic and the perpendicular dielectric profile exhibits pronounced oscillations and sign changes. The interfacial dielectric excess, characterized by the shift of the dielectric-dividing-surface with respect to the Gibbs-dividing-surface, is positive for all surfaces, showing that water has an enhanced dielectric response at hydrophobic surfaces. The dielectric-dividing-surface positions vary significantly among the different surfaces, which points to pronounced surface-specific dielectric behavior. The interfacial repulsion of a chloride ion is shown to be dominated by electrostatic interactions for the soft fluid-fluid interfaces and by non-electrostatic Lennard-Jones interactions for the rigid graphene-water interface. A linear tensorial dielectric model for the ion-interface interaction with sharp dielectric interfaces located on the dielectric-dividing-surface positions works well for graphene but fails for vapor and hexane, because these interfaces are smeared out. The repulsion of chloride from the metallic and non-metallic graphite versions differs very little, which reflects the almost identical interfacial water structure and can be understood based on linear continuum dielectric theory. Interface flexibility shows up mostly in the non-linear Coulomb part of the ion-interface interaction, which changes significantly close to the interfaces and signals the breakdown of linear dielectric continuum theory.
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Affiliation(s)
| | - Laura Scalfi
- Freie Universitat Berlin Fachbereich Physik, Germany
| | | | - Otto Schullian
- Max Planck Institute of Colloids and Interfaces, Germany
| | - Douwe Bonthuis
- Institute of Theoretical and Computational Physics, Graz University of Technology Institute of Theoretical and Computational Physics, Austria
| | | | - Roland R. Netz
- Physics, Freie Universitat Berlin Fachbereich Physik, Germany
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15
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Adam L, Müller E, Ludwig K, Klenk S, Lauster D, Liese S, Herrmann A, Hackenberger CPR. Design and Functional Analysis of Heterobifunctional Multivalent Phage Capsid Inhibitors Blocking the Entry of Influenza Virus. Bioconjug Chem 2022; 33:1269-1278. [PMID: 35759354 PMCID: PMC9305970 DOI: 10.1021/acs.bioconjchem.2c00166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
![]()
Multiple conjugation
of virus-binding ligands to multivalent carriers
is a prominent strategy to construct highly affine virus binders for
the inhibition of viral entry into host cells. In a previous study,
we introduced rationally designed sialic acid conjugates of bacteriophages
(Qβ) that match the triangular binding site geometry on hemagglutinin
spike proteins of influenza A virions, resulting in effective infection
inhibition in vitro and in vivo.
In this work, we demonstrate that even partially sialylated Qβ
conjugates retain the inhibitory effect despite reduced activity.
These observations not only support the importance of trivalent binding
events in preserving high affinity, as supported by computational
modeling, but also allow us to construct heterobifunctional modalities.
Capsids carrying two different sialic acid ligand–linker structures
showed higher viral inhibition than their monofunctional counterparts.
Furthermore, capsids carrying a fluorescent dye in addition to sialic
acid ligands were used to track their interaction with cells. These
findings support exploring broader applications as multivalent inhibitors
in the future.
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Affiliation(s)
- Lutz Adam
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Straße 10, 13125 Berlin, Germany.,Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Street 2, 12489 Berlin, Germany
| | - Eva Müller
- Institut für translationale HIV Forschung, Universitätsklinikum Essen, Virchowstree 171, 45147 Essen, Germany
| | - Kai Ludwig
- Forschungszentrum für Elektronenmikroskopie und Gerätezentrum BioSupraMol, Institut für Chemie und Biochemie, Freie Universität Berlin, Berlin 14195, Germany
| | - Simon Klenk
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Straße 10, 13125 Berlin, Germany.,Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Street 2, 12489 Berlin, Germany
| | - Daniel Lauster
- Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany
| | - Susanne Liese
- Max-Planck Institute for the Physics of Complex Systems, Nöthnitzer Street 38, Dresden 01187, Germany.,Institut für Physik, Universität Augsburg, Augsburg 86159, Germany
| | - Andreas Herrmann
- Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany
| | - Christian P R Hackenberger
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Straße 10, 13125 Berlin, Germany.,Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Street 2, 12489 Berlin, Germany
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16
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Nishida K, Anada T, Tanaka M. Roles of interfacial water states on advanced biomedical material design. Adv Drug Deliv Rev 2022; 186:114310. [PMID: 35487283 DOI: 10.1016/j.addr.2022.114310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 04/12/2022] [Accepted: 04/21/2022] [Indexed: 12/15/2022]
Abstract
When biomedical materials come into contact with body fluids, the first reaction that occurs on the material surface is hydration; proteins are then adsorbed and denatured on the hydrated material surface. The amount and degree of denaturation of adsorbed proteins affect subsequent cell behavior, including cell adhesion, migration, proliferation, and differentiation. Biomolecules are important for understanding the interactions and biological reactions of biomedical materials to elucidate the role of hydration in biomedical materials and their interaction partners. Analysis of the water states of hydrated materials is complicated and remains controversial; however, knowledge about interfacial water is useful for the design and development of advanced biomaterials. Herein, we summarize recent findings on the hydration of synthetic polymers, supramolecular materials, inorganic materials, proteins, and lipid membranes. Furthermore, we present recent advances in our understanding of the classification of interfacial water and advanced polymer biomaterials, based on the intermediate water concept.
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Affiliation(s)
- Kei Nishida
- Institute for Materials Chemistry and Engineering Kyushu university, 744 Motooka, Nishi-ku Fukuoka 819-0395, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, Japan(1)
| | - Takahisa Anada
- Institute for Materials Chemistry and Engineering Kyushu university, 744 Motooka, Nishi-ku Fukuoka 819-0395, Japan
| | - Masaru Tanaka
- Institute for Materials Chemistry and Engineering Kyushu university, 744 Motooka, Nishi-ku Fukuoka 819-0395, Japan.
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17
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Cao N, Zhao Y, Chen H, Huang J, Yu M, Bao Y, Wang D, Cui S. Poly(ethylene glycol) Becomes a Supra-Polyelectrolyte by Capturing Hydronium Ions in Water. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nanpu Cao
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education), Southwest Jiaotong University, Chengdu 610031, China
| | - Yuehua Zhao
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
| | - Hongbo Chen
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
| | - Jinying Huang
- School of Optoelectronic Science, Changchun College of Electronic Technology, Changchun 130114, China
| | - Miao Yu
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education), Southwest Jiaotong University, Chengdu 610031, China
| | - Yu Bao
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education), Southwest Jiaotong University, Chengdu 610031, China
| | - Dapeng Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
| | - Shuxun Cui
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education), Southwest Jiaotong University, Chengdu 610031, China
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18
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Bao Y, Huang X, Xu D, Xu J, Jiang L, Lu ZY, Cui S. Bound water governs the single-chain property of Poly(vinyl alcohol) in aqueous environments. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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19
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Yang J, Wang Y, Qian HJ, Lu ZY, Gong Z, Liu H, Cui S. Force-induced hydrogen bonding between single polyformaldehyde chain and water. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Molecular dynamics simulations of the evaporation of hydrated ions from aqueous solution. Commun Chem 2022; 5:55. [PMID: 36698011 PMCID: PMC9814746 DOI: 10.1038/s42004-022-00669-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 03/22/2022] [Indexed: 01/28/2023] Open
Abstract
Although important for atmospheric processes and gas-phase catalysis, very little is known about the hydration state of ions in the vapor phase. Here we study the evaporation energetics and kinetics of a chloride ion from liquid water by molecular dynamics simulations. As chloride permeates the interface, a water finger forms and breaks at a chloride separation of ≈ 2.8 nm from the Gibbs dividing surface. For larger separations from the interface, about 7 water molecules are estimated to stay bound to chloride in saturated water vapor, as corroborated by continuum dielectrics and statistical mechanics models. This ion hydration significantly reduces the free-energy barrier for evaporation. The effective chloride diffusivity in the transition state is found to be about 6 times higher than in bulk, which reflects the highly mobile hydration dynamics as the water finger breaks. Both effects significantly increase the chloride evaporation flux from the quiescent interface of an electrolyte solution, which is predicted from reaction kinetic theory.
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21
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Lallemang M, Yu L, Cai W, Rischka K, Hartwig A, Haag R, Hugel T, Balzer BN. Multivalent non-covalent interactions lead to strongest polymer adhesion. NANOSCALE 2022; 14:3768-3776. [PMID: 35171194 DOI: 10.1039/d1nr08338d] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Multivalent interactions play a leading role in biological processes such as the inhibition of inflammation or virus internalization. The multivalent interactions show enhanced strength and better selectivity compared to monovalent interactions, but they are much less understood due to their complexity. Here, we detect molecular interactions in the range of a few piconewtons to several nanonewtons and correlate them with the formation and subsequent breaking of one or several bonds and assign these bonds. This becomes possible by performing atomic force microcopy (AFM)-based single molecule force spectroscopy of a multifunctional polymer covalently attached to an AFM cantilever tip on a substrate bound polymer layer of the multifunctional polymer. Varying the pH value and the crosslinking state of the polymer layer, we find that bonds of intermediate strength (non-covalent), like coordination bonds, give the highest multivalent bond strength, even outperforming strong (covalent) bonds. At the same time, covalent bonds enhance the polymer layer density, increasing in particular the number of non-covalent bonds. In summary, we can show that the key for the design of stable and durable polymer coatings is to provide a variety of multivalent interactions and to keep the number of non-covalent interactions at a high level.
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Affiliation(s)
- Max Lallemang
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany.
- Cluster of Excellence livMatS @ FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
| | - Leixiao Yu
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takusstraße 3, 14195 Berlin, Germany
| | - Wanhao Cai
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany.
| | - Klaus Rischka
- Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Wiener Straße 12, 28359 Bremen, Germany
| | - Andreas Hartwig
- Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Wiener Straße 12, 28359 Bremen, Germany
- University of Bremen, Department 2 Biology/Chemistry, Leobener Straße 3, 28359 Bremen, Germany
| | - Rainer Haag
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takusstraße 3, 14195 Berlin, Germany
| | - Thorsten Hugel
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany.
- Cluster of Excellence livMatS @ FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
| | - Bizan N Balzer
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany.
- Cluster of Excellence livMatS @ FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
- Freiburg Materials Research Center (FMF), Albert Ludwig University of Freiburg, 79104 Freiburg, Germany
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22
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Piechocki K, Koynov K, Piechocka J, Chamerski K, Filipecki J, Maczugowska P, Kozanecki M. Small molecule diffusion in poly-(olygo ethylene glycol methacrylate) based hydrogels studied by fluorescence correlation spectroscopy. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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23
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Bleha T, Cifra P. Energy/entropy partition of force at DNA stretching. Biopolymers 2022; 113:e23487. [PMID: 35212392 DOI: 10.1002/bip.23487] [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: 11/28/2021] [Revised: 02/03/2022] [Accepted: 02/16/2022] [Indexed: 11/09/2022]
Abstract
We compute by molecular simulation the energy/entropic partition of the force in a stretched double-stranded (ds)DNA molecule that is not yet available from the single-molecule measurements. Simulation using the coarse-grained wormlike chain (WLC) model predicts a gradual decrease in the internal (bending) energy of DNA at stretching. The ensuing negative energy contribution to force fU is outweighed by the positive entropy contribution fS . The ratio fU /f, used to assess the polymer elasticity, is about -1 at the moderate extension of DNA. At the high extension, the extra energy expenses due to the contour length elongation make the ratio fU /f less negative. The simulation findings of the hybrid energy/entropy nature of DNA elasticity at weak and moderate forces are supported by computations using the thermoelastic method mimicking the polymer experiments in bulk. It is contended that the observation of the negative energy elasticity in DNA can be generalized to other semiflexible polymers described by the WLC model.
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Affiliation(s)
- Tomas Bleha
- Polymer Institute, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Peter Cifra
- Polymer Institute, Slovak Academy of Sciences, Bratislava, Slovakia
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24
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Luo Y, Pang AP, Zhu P, Wang D, Lu X. Demonstrating the Interfacial Polymer Thermal Transition from Coil-to-Globule to Coil-to-Stretch under Shear Flow Using SFG and MD Simulation. J Phys Chem Lett 2022; 13:1617-1627. [PMID: 35142518 DOI: 10.1021/acs.jpclett.1c03866] [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] [Indexed: 06/14/2023]
Abstract
Revealing interfacial shear-induced structural responsiveness has long been an important topic in that most fluids in nature and human life are in motion and cause interesting boundary phenomena. It is amazing how the polymer chain conformation or local structural features at a boundary change under the effective shear condition. In this study, microfluidic-assisted sum frequency generation (SFG) vibrational spectroscopy and all-atom molecular dynamics (MD) simulation are combined to reveal that the shear flow can effectively block the so-called thermal coil-to-globule transition of the poly(N-isopropylacrylamide) (PNIPAM) brushes on the solid substrate, and the normal coil-to-globule transition transfers to a coil-to-stretch one under shear flow with increasing ambient temperature. Such findings are attributed to the balance between the shear flow and the molecular interaction with respect to the polymer chains and adjacent water molecules, thus demonstrating the significant effect of the shear flow on the structural and dynamic behaviors of the polymer chains at the boundaries from the molecular level.
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Affiliation(s)
- Yongsheng Luo
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
| | - Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
| | - Peizhi Zhu
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225009, Jiangsu Province, P. R. China
| | - Dayang Wang
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, Jilin Province, P. R. China
| | - Xiaolin Lu
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
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25
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Experimental and theoretical studies of pegylated-β-cyclodextrin: A step forward to understand its tunable self-aggregation abilities. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2021.102975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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26
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Cai W, Bullerjahn JT, Lallemang M, Kroy K, Balzer BN, Hugel T. Angle-dependent strength of a single chemical bond by stereographic force spectroscopy. Chem Sci 2022; 13:5734-5740. [PMID: 35694336 PMCID: PMC9117962 DOI: 10.1039/d2sc01077a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 04/13/2022] [Indexed: 11/21/2022] Open
Abstract
A wealth of chemical bonds and polymers have been studied with single-molecule force spectroscopy, usually by applying a force perpendicular to the anchoring surface. However, the direction-dependence of the bond strength lacks fundamental understanding. Here we establish stereographic force spectroscopy to study the single-bond strength for various pulling angles. Surprisingly, we find that the apparent bond strength increases with increasing pulling angle relative to the anchoring surface normal, indicating a sturdy mechanical anisotropy of a chemical bond. This finding can be rationalized by a fixed pathway for the rupture of the bond, resulting in an effective projection of the applied pulling force onto a nearly fixed rupture direction. Our study is fundamental for the molecular understanding of the role of the direction of force application in molecular adhesion and friction. It is also a prerequisite for the nanoscale tailoring of the anisotropic strength of bottom-up designed materials. Stereographic force spectroscopy reveals that a chemical bond ruptures along a fixed pathway such that the apparent bond strength strongly depends on the angle of force application.![]()
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Affiliation(s)
- Wanhao Cai
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Jakob T. Bullerjahn
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, 60438, Frankfurt am Main, Germany
| | - Max Lallemang
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
- Cluster of Excellence livMatS@FIT – Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110, Freiburg, Germany
| | - Klaus Kroy
- Institute for Theoretical Physics, Leipzig University, Brüderstraße 16, 04103, Leipzig, Germany
| | - Bizan N. Balzer
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
- Cluster of Excellence livMatS@FIT – Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110, Freiburg, Germany
- Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104, Freiburg, Germany
| | - Thorsten Hugel
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
- Cluster of Excellence livMatS@FIT – Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110, Freiburg, Germany
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27
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van der Sleen LM, Tych KM. Bioconjugation Strategies for Connecting Proteins to DNA-Linkers for Single-Molecule Force-Based Experiments. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:2424. [PMID: 34578744 PMCID: PMC8464727 DOI: 10.3390/nano11092424] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 01/10/2023]
Abstract
The mechanical properties of proteins can be studied with single molecule force spectroscopy (SMFS) using optical tweezers, atomic force microscopy and magnetic tweezers. It is common to utilize a flexible linker between the protein and trapped probe to exclude short-range interactions in SMFS experiments. One of the most prevalent linkers is DNA due to its well-defined properties, although attachment strategies between the DNA linker and protein or probe may vary. We will therefore provide a general overview of the currently existing non-covalent and covalent bioconjugation strategies to site-specifically conjugate DNA-linkers to the protein of interest. In the search for a standardized conjugation strategy, considerations include their mechanical properties in the context of SMFS, feasibility of site-directed labeling, labeling efficiency, and costs.
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Affiliation(s)
| | - Katarzyna M. Tych
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, The Netherlands;
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28
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Niu WA, Rivera SL, Siegrist MS, Santore MM. Depletion forces drive reversible capture of live bacteria on non-adhesive surfaces. SOFT MATTER 2021; 17:8185-8194. [PMID: 34525168 DOI: 10.1039/d1sm00631b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Because bacterial adhesion to surfaces is associated with infections and biofilm growth, it has been a longstanding goal to develop coatings that minimize biomolecular adsorption and eliminate bacteria adhesion. We demonstrate that, even on carefully-engineered non-bioadhesive coatings such as polyethylene glycol (PEG) layers that prevent biomolecule adsorption and cell adhesion, depletion interactions from non-adsorbing polymer in solution (such as 10 K PEG or 100 K PEO) can cause adhesion and retention of Escherichia coli cells, defeating the antifouling functionality of the coating. The cells are immobilized and remain viable on the timescale of the study, at least up to 45 minutes. When the polymer solution is replaced by buffer, cells rapidly escape from the surface, consistent with expectations for the reversibility of depletion attractions. The dissolved polymer additionally causes cells to aggregate in solution and aggregates rapidly dissociate to singlets upon tenfold dilution in buffer, also consistent with depletion. Hydrodynamic forces can substantially reduce the adhesion of aggregates on surfaces in conditions where single cells adhere via depletion. The findings reported here suggest that because bacteria thrive in polymer-rich environments both in vivo and in situ, depletion interactions may make it impossible to avoid bacterial retention on surfaces.
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Affiliation(s)
- Wuqi Amy Niu
- Department of Polymer Science and Engineering, University of Massachusetts, Governors Drive, Amherst, MA 01003, USA.
| | - Sylvia L Rivera
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
| | - M Sloan Siegrist
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA 01003, USA
| | - Maria M Santore
- Department of Polymer Science and Engineering, University of Massachusetts, Governors Drive, Amherst, MA 01003, USA.
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA 01003, USA
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29
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Molecular dynamics of poly(2-(2-methoxyethoxy)ethyl methacrylate) hydrogels studied by broadband dielectric spectroscopy. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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30
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Wettstein A, Diddens D, Heuer A. Polymer Electrolytes in Strong External Electric Fields: Modification of Structure and Dynamics. Macromolecules 2021. [DOI: 10.1021/acs.macromol.0c02385] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alina Wettstein
- Institut für Physikalische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 28/30, D-48149 Münster, Germany
| | - Diddo Diddens
- Institut für Energie- und Klimaforschung, Ionics in Energy Storage, Helmholtz Institut Münster, Forschungszentrum Jülich, Corrensstraße 46, 48149 Münster, Germany
| | - Andreas Heuer
- Institut für Physikalische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 28/30, D-48149 Münster, Germany
- Institut für Energie- und Klimaforschung, Ionics in Energy Storage, Helmholtz Institut Münster, Forschungszentrum Jülich, Corrensstraße 46, 48149 Münster, Germany
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31
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Wolde-Kidan A, Herrmann A, Prause A, Gradzielski M, Haag R, Block S, Netz RR. Particle Diffusivity and Free-Energy Profiles in Hydrogels from Time-Resolved Penetration Data. Biophys J 2021; 120:463-475. [PMID: 33421414 PMCID: PMC7896003 DOI: 10.1016/j.bpj.2020.12.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 12/19/2020] [Accepted: 12/23/2020] [Indexed: 02/02/2023] Open
Abstract
A combined experimental and theoretical method to simultaneously determine diffusivity and free-energy profiles of particles that penetrate into inhomogeneous hydrogel systems is presented. As the only input, arbitrarily normalized concentration profiles from fluorescence intensity data of labeled tracer particles for different penetration times are needed. The method is applied to dextran molecules of varying size that penetrate into hydrogels of polyethylene-glycol chains with different lengths that are covalently cross-linked by hyperbranched polyglycerol hubs. Extracted dextran bulk diffusivities agree well with fluorescence correlation spectroscopy data obtained separately. Empirical scaling laws for dextran diffusivities and free energies inside the hydrogel are identified as a function of the dextran mass. An elastic free-volume model that includes dextran as well as polyethylene-glycol linker flexibility quantitively describes the repulsive dextran-hydrogel interaction free energy, which is of steric origin, and furthermore suggests that the hydrogel mesh-size distribution is rather broad and particle penetration is dominated by large hydrogel pores. Particle penetration into hydrogels for steric particle-hydrogel interactions is thus suggested to be governed by an elastic size-filtering mechanism that involves the tail of the hydrogel pore-size distribution.
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Affiliation(s)
| | - Anna Herrmann
- Institut für Chemie und Biochemie, Freie Universität Berlin, Berlin, Germany
| | - Albert Prause
- Institut für Chemie, Technische Universität Berlin, Berlin, Germany
| | | | - Rainer Haag
- Institut für Chemie und Biochemie, Freie Universität Berlin, Berlin, Germany
| | - Stephan Block
- Institut für Chemie und Biochemie, Freie Universität Berlin, Berlin, Germany
| | - Roland R Netz
- Fachbereich Physik, Freie Universität Berlin, Berlin, Germany.
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Dunderdale GJ, Davidson SJ, Ryan AJ, Mykhaylyk OO. Flow-induced crystallisation of polymers from aqueous solution. Nat Commun 2020; 11:3372. [PMID: 32632091 PMCID: PMC7338548 DOI: 10.1038/s41467-020-17167-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 06/16/2020] [Indexed: 11/21/2022] Open
Abstract
Synthetic polymers are thoroughly embedded in the modern society and their consumption grows annually. Efficient routes to their production and processing have never been more important. In this respect, silk protein fibrillation is superior to conventional polymer processing, not only by achieving outstanding physical properties of materials, such as high tensile strength and toughness, but also improved process energy efficiency. Natural silk solidifies in response to flow of the liquid using conformation-dependent intermolecular interactions to desolvate (denature) protein chains. This mechanism is reproduced here by an aqueous poly(ethylene oxide) (PEO) solution, which solidifies at ambient conditions when subjected to flow. The transition requires that an energy threshold is exceeded by the flow conditions, which disrupts a protective hydration shell around polymer molecules, releasing them from a metastable state into the thermodynamically favoured crystalline state. This mechanism requires vastly lower energy inputs and demonstrates an alternative route for polymer processing.
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Affiliation(s)
- Gary J Dunderdale
- Department of Chemistry, The University of Sheffield, Sheffield, S3 7HF, UK
| | - Sarah J Davidson
- Department of Chemistry, The University of Sheffield, Sheffield, S3 7HF, UK
- Croda International Plc, Snaith, Goole, DN14 9AA, UK
| | - Anthony J Ryan
- Department of Chemistry, The University of Sheffield, Sheffield, S3 7HF, UK
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33
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Schwarzl R, Liese S, Brünig FN, Laudisio F, Netz RR. Force Response of Polypeptide Chains from Water-Explicit MD Simulations. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Richard Schwarzl
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Susanne Liese
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
- Department of Mathematics, University of Oslo, 0851 Oslo, Norway
| | - Florian N. Brünig
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Fabio Laudisio
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Roland R. Netz
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
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34
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Yang B, Liu Z, Liu H, Nash MA. Next Generation Methods for Single-Molecule Force Spectroscopy on Polyproteins and Receptor-Ligand Complexes. Front Mol Biosci 2020; 7:85. [PMID: 32509800 PMCID: PMC7248566 DOI: 10.3389/fmolb.2020.00085] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 04/16/2020] [Indexed: 12/31/2022] Open
Abstract
Single-molecule force spectroscopy with the atomic force microscope provides molecular level insights into protein function, allowing researchers to reconstruct energy landscapes and understand functional mechanisms in biology. With steadily advancing methods, this technique has greatly accelerated our understanding of force transduction, mechanical deformation, and mechanostability within single- and multi-domain polyproteins, and receptor-ligand complexes. In this focused review, we summarize the state of the art in terms of methodology and highlight recent methodological improvements for AFM-SMFS experiments, including developments in surface chemistry, considerations for protein engineering, as well as theory and algorithms for data analysis. We hope that by condensing and disseminating these methods, they can assist the community in improving data yield, reliability, and throughput and thereby enhance the information that researchers can extract from such experiments. These leading edge methods for AFM-SMFS will serve as a groundwork for researchers cognizant of its current limitations who seek to improve the technique in the future for in-depth studies of molecular biomechanics.
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Affiliation(s)
- Byeongseon Yang
- Department of Chemistry, University of Basel, Basel, Switzerland
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Zhaowei Liu
- Department of Chemistry, University of Basel, Basel, Switzerland
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Haipei Liu
- Department of Chemistry, University of Basel, Basel, Switzerland
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Michael A. Nash
- Department of Chemistry, University of Basel, Basel, Switzerland
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
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35
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Bao Y, Luo Z, Cui S. Environment-dependent single-chain mechanics of synthetic polymers and biomacromolecules by atomic force microscopy-based single-molecule force spectroscopy and the implications for advanced polymer materials. Chem Soc Rev 2020; 49:2799-2827. [PMID: 32236171 DOI: 10.1039/c9cs00855a] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
"The Tao begets the One. One begets all things of the world." This quote from Tao Te Ching is still inspiring for scientists in chemistry and materials science: The "One" can refer to a single molecule. A macroscopic material is composed of numerous molecules. Although the relationship between the properties of the single molecule and macroscopic material is not well understood yet, it is expected that a deeper understanding of the single-chain mechanics of macromolecules will certainly facilitate the development of materials science. Atomic force microscopy-based single-molecule force spectroscopy (AFM-SMFS) has been exploited extensively as a powerful tool to study the single-chain behaviors of macromolecules. In this review, we summarize the recent advances in the emerging field of environment-dependent single-chain mechanics of synthetic polymers and biomacromolecules by means of AFM-SMFS. First, the single-chain inherent elasticities of several typical linear macromolecules are introduced, which are also confirmed by one of three polymer models with theoretical elasticities of the corresponding macromolecules obtained from quantum mechanical (QM) calculations. Then, the effects of the external environments on the single-chain mechanics of synthetic polymers and biomacromolecules are reviewed. Finally, the impacts of single-chain mechanics of macromolecules on the development of polymer science especially polymer materials are illustrated.
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Affiliation(s)
- Yu Bao
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China.
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36
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Thermophoresis: The Case of Streptavidin and Biotin. Polymers (Basel) 2020; 12:polym12020376. [PMID: 32046223 PMCID: PMC7077373 DOI: 10.3390/polym12020376] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/27/2020] [Accepted: 01/29/2020] [Indexed: 02/02/2023] Open
Abstract
Thermophoretic behavior of a free protein changes upon ligand binding and gives access to information on the binding constants. The Soret effect has also been proven to be a promising tool to gain information on the hydration layer, as the temperature dependence of the thermodiffusion behavior is sensitive to solute–solvent interactions. In this work, we perform systematic thermophoretic measurements of the protein streptavidin (STV) and of the complex STV with biotin (B) using thermal diffusion forced Rayleigh scattering (TDFRS). Our experiments show that the temperature sensitivity of the Soret coefficient is reduced for the complex compared to the free protein. We discuss our data in comparison with recent quasi-elastic neutron scattering (QENS) measurements. As the QENS measurement has been performed in heavy water, we perform additional measurements in water/heavy water mixtures. Finally, we also elucidate the challenges arising from the quantiative thermophoretic study of complex multicomponent systems such as protein solutions.
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37
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Blanco PM, Madurga S, Mas F, Garcés JL. Effect of Charge Regulation and Conformational Equilibria in the Stretching Properties of Weak Polyelectrolytes. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01160] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Pablo M. Blanco
- Physical Chemistry Unit, Materials Science and Physical Chemistry Department & Research Institute of Theoretical and Computational Chemistry (IQTCUB) of Barcelona University (UB), Barcelona 08028, Catalonia, Spain
| | - Sergio Madurga
- Physical Chemistry Unit, Materials Science and Physical Chemistry Department & Research Institute of Theoretical and Computational Chemistry (IQTCUB) of Barcelona University (UB), Barcelona 08028, Catalonia, Spain
| | - Francesc Mas
- Physical Chemistry Unit, Materials Science and Physical Chemistry Department & Research Institute of Theoretical and Computational Chemistry (IQTCUB) of Barcelona University (UB), Barcelona 08028, Catalonia, Spain
| | - Josep L. Garcés
- Chemistry Department, Technical School of Agricultural Engineering & AGROTECNIO of Lleida University (UdL), Lleida 25198, Catalonia, Spain
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38
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Cai W, Lu S, Wei J, Cui S. Single-Chain Polymer Models Incorporating the Effects of Side Groups: An Approach to General Polymer Models. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01542] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Wanhao Cai
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Song Lu
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Junhao Wei
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Shuxun Cui
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
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39
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Çolak A, Li B, Blass J, Koynov K, Del Campo A, Bennewitz R. The mechanics of single cross-links which mediate cell attachment at a hydrogel surface. NANOSCALE 2019; 11:11596-11604. [PMID: 31169854 DOI: 10.1039/c9nr01784d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The response of cultured cells to the mechanical properties of hydrogel substrates depends ultimately on the response of single crosslinks to external forces exerted at cell attachment points. We prepared hydrogels by co-polymerization of poly(ethylene glycol diacrylate) (PEGDA) and carboxy poly(ethylene glycol) acrylate (ACPEG-COOH) and confirmed fibroblast spreading on the hydrogel after the ACPEG linker was functionalized with the RGD cell adhesive motif. We performed specific force spectroscopy experiments on the same ACPEG linkers in order to probe the mechanics of single cross-links which mediate the cell attachment and spreading. Measurements were performed with tips of an atomic force microscope (AFM) functionalized with streptavidin and ACPEG linkers functionalized with biotin. We compared hydrogels of varying elastic modulus between 4 and 41 kPa which exhibited significant differences in cell spreading. An effective spring constant for the displacement of single cross-links at the hydrogel surface was derived from the distributions of rupture force and molecular stiffness. A factor of ten in the elastic modulus E of the hydrogel corresponded to a factor of five in the effective spring constant k of single crosslinks, indicating a transition in scaling with the mesh size ξ from the macroscopic E∝ξ-3 to the molecular k∝ξ-2. The quantification of stiffness and deformation at the molecular length scale contributes to the discussion of mechanisms in force-regulated phenomena in cell biology.
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Affiliation(s)
- Arzu Çolak
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
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40
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Kolberg A, Wenzel C, Hackenstrass K, Schwarzl R, Rüttiger C, Hugel T, Gallei M, Netz RR, Balzer BN. Opposing Temperature Dependence of the Stretching Response of Single PEG and PNiPAM Polymers. J Am Chem Soc 2019; 141:11603-11613. [DOI: 10.1021/jacs.9b04383] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Adrianna Kolberg
- Institute of Physical Chemistry, Albert-Ludwigs-Universität Freiburg, Albertstraße 23a, 79104 Freiburg, Germany
| | - Christiane Wenzel
- Institute of Physical Chemistry, Albert-Ludwigs-Universität Freiburg, Albertstraße 23a, 79104 Freiburg, Germany
| | - Klara Hackenstrass
- Institute of Physical Chemistry, Albert-Ludwigs-Universität Freiburg, Albertstraße 23a, 79104 Freiburg, Germany
| | - Richard Schwarzl
- Department Institute of Theoretical Bio- and Soft Matter Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Christian Rüttiger
- Ernst-Berl-Institute of Technical and Macromolecular Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
| | - Thorsten Hugel
- Institute of Physical Chemistry, Albert-Ludwigs-Universität Freiburg, Albertstraße 23a, 79104 Freiburg, Germany
- Cluster of Excellence livMatS@FIT, Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
| | - Markus Gallei
- Ernst-Berl-Institute of Technical and Macromolecular Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
- Organic Macromolecular Chemistry, Saarland University, Campus Saarbrücken C4 2, 66123 Saarbrücken, Germany
| | - Roland R. Netz
- Department Institute of Theoretical Bio- and Soft Matter Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Bizan N. Balzer
- Institute of Physical Chemistry, Albert-Ludwigs-Universität Freiburg, Albertstraße 23a, 79104 Freiburg, Germany
- Cluster of Excellence livMatS@FIT, Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
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41
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Reiter-Scherer V, Cuellar-Camacho JL, Bhatia S, Haag R, Herrmann A, Lauster D, Rabe JP. Force Spectroscopy Shows Dynamic Binding of Influenza Hemagglutinin and Neuraminidase to Sialic Acid. Biophys J 2019; 116:1037-1048. [PMID: 30799074 DOI: 10.1016/j.bpj.2019.01.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 11/30/2018] [Accepted: 01/14/2019] [Indexed: 10/27/2022] Open
Abstract
The influenza A virus infects target cells through multivalent interactions of its major spike proteins, hemagglutinin (HA) and neuraminidase (NA), with the cellular receptor sialic acid (SA). HA is known to mediate the attachment of the virion to the cell, whereas NA enables the release of newly formed virions by cleaving SA from the cell. Because both proteins target the same receptor but have antagonistic functions, virus infection depends on a properly tuned balance of the kinetics of HA and NA activities for viral entry to and release from the host cell. Here, dynamic single-molecule force spectroscopy, based on scanning force microscopy, was employed to determine these bond-specific kinetics, characterized by the off rate koff, rupture length xβ and on rate kon, as well as the related free-energy barrier ΔG and the dissociation constant KD. Measurements were conducted using surface-immobilized HA and NA of the influenza A virus strain A/California/04/2009 and a novel, to our knowledge, synthetic SA-displaying receptor for functionalization of the force probe. Single-molecule force spectroscopy at force loading rates between 100 and 50,000 pN/s revealed most probable rupture forces of the protein-SA bond in the range of 10-100 pN. Using an extension of the widely applied Bell-Evans formalism by Friddle, De Yoreo, and co-workers, it is shown that HA features a smaller xβ, a larger koff and a smaller ΔG than NA. Measurements of the binding probability at increasing contact time between the scanning force microscopy force probe and the surface allow an estimation of KD, which is found to be three times as large for HA than for NA. This suggests a stronger interaction for NA-SA than for HA-SA. The biological implications in regard to virus binding to the host cell and the release of new virions from the host cell are discussed.
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Affiliation(s)
| | | | - Sumati Bhatia
- Department of Chemistry, Freie Universität Berlin, Berlin, Germany
| | - Rainer Haag
- Department of Chemistry, Freie Universität Berlin, Berlin, Germany
| | - Andreas Herrmann
- Department of Biology and IRI Life Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Daniel Lauster
- Department of Biology and IRI Life Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.
| | - Jürgen P Rabe
- Department of Physics and IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin, Germany.
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42
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Kiran P, Bhatia S, Lauster D, Aleksić S, Fleck C, Peric N, Maison W, Liese S, Keller BG, Herrmann A, Haag R. Exploring Rigid and Flexible Core Trivalent Sialosides for Influenza Virus Inhibition. Chemistry 2018; 24:19373-19385. [PMID: 30295350 PMCID: PMC6587447 DOI: 10.1002/chem.201804826] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Indexed: 12/25/2022]
Abstract
Herein, the chemical synthesis and binding analysis of functionalizable rigid and flexible core trivalent sialosides bearing oligoethylene glycol (OEG) spacers interacting with spike proteins of influenza A virus (IAV) X31 is described. Although the flexible Tris-based trivalent sialosides achieved micromolar binding constants, a trivalent binder based on a rigid adamantane core dominated flexible tripodal compounds with micromolar binding and hemagglutination inhibition constants. Simulation studies indicated increased conformational penalties for long OEG spacers. Using a systematic approach with molecular modeling and simulations as well as biophysical analysis, these findings emphasize on the importance of the scaffold rigidity and the challenges associated with the spacer length optimization.
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Affiliation(s)
- Pallavi Kiran
- Institut für Chemie und Biochemie Organische ChemieFreie Universität BerlinTakustr. 314195BerlinGermany
| | - Sumati Bhatia
- Institut für Chemie und Biochemie Organische ChemieFreie Universität BerlinTakustr. 314195BerlinGermany
| | - Daniel Lauster
- Institut für Biologie, Molekulare Biophysik, IRI Life SciencesHumboldt-Universität zu BerlinInvalidenstr. 4210115BerlinGermany
| | - Stevan Aleksić
- Institut für Chemie und Biochemie, Physikalische und Theoretische ChemieFreie Universität BerlinTakustr. 314195BerlinGermany
| | - Carsten Fleck
- Fachbereich ChemieInstitut für PharmazieUniversität HamburgBundesstr. 4520146HamburgGermany
| | - Natalija Peric
- Fachbereich ChemieInstitut für PharmazieUniversität HamburgBundesstr. 4520146HamburgGermany
| | - Wolfgang Maison
- Fachbereich ChemieInstitut für PharmazieUniversität HamburgBundesstr. 4520146HamburgGermany
| | - Susanne Liese
- Department of MathematicsUniversity of Oslo, P.O Box1053 Blinder0316OsloNorway
- Department of PhysicsFreie Universität BerlinArnimallee 1414195BerlinGermany
| | - Bettina G. Keller
- Institut für Chemie und Biochemie, Physikalische und Theoretische ChemieFreie Universität BerlinTakustr. 314195BerlinGermany
| | - Andreas Herrmann
- Institut für Biologie, Molekulare Biophysik, IRI Life SciencesHumboldt-Universität zu BerlinInvalidenstr. 4210115BerlinGermany
| | - Rainer Haag
- Institut für Chemie und Biochemie Organische ChemieFreie Universität BerlinTakustr. 314195BerlinGermany
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43
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Li B, Wang X, Li Y, Paananen A, Szilvay GR, Qin M, Wang W, Cao Y. Single-Molecule Force Spectroscopy Reveals Self-Assembly Enhanced Surface Binding of Hydrophobins. Chemistry 2018; 24:9224-9228. [PMID: 29687928 DOI: 10.1002/chem.201801730] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Indexed: 01/26/2023]
Abstract
Hydrophobins have raised lots of interest as powerful surface adhesives. However, it remains largely unexplored how their strong and versatile surface adhesion is linked to their unique amphiphilic structural features. Here, we develop an AFM-based single-molecule force spectroscopy assay to quantitatively measure the binding strength of hydrophobin to various types of surfaces both in isolation and in preformed protein films. We find that individual class II hydrophobins (HFBI) bind strongly to hydrophobic surfaces but weakly to hydrophilic ones. After self-assembly into protein films, they show much stronger binding strength to both surfaces due to the cooperativity of different interactions at nanoscale. Such self-assembly enhanced surface binding may serve as a general design principle for synthetic bioactive adhesives.
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Affiliation(s)
- Bing Li
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| | - Xin Wang
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| | - Ying Li
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, Jiangsu, 210044, P. R. China
| | - Arja Paananen
- Industrial Biotechnology, VTT Technical Research Centre of Finland Ltd, 02044 VTT, Espoo, Finland
| | - Géza R Szilvay
- Industrial Biotechnology, VTT Technical Research Centre of Finland Ltd, 02044 VTT, Espoo, Finland
| | - Meng Qin
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| | - Wei Wang
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| | - Yi Cao
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
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44
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Liese S, Netz RR. Quantitative Prediction of Multivalent Ligand-Receptor Binding Affinities for Influenza, Cholera, and Anthrax Inhibition. ACS NANO 2018; 12:4140-4147. [PMID: 29474056 DOI: 10.1021/acsnano.7b08479] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Multivalency achieves strong, yet reversible binding by the simultaneous formation of multiple weak bonds. It is a key interaction principle in biology and promising for the synthesis of high-affinity inhibitors of pathogens. We present a molecular model for the binding affinity of synthetic multivalent ligands onto multivalent receptors consisting of n receptor units arranged on a regular polygon. Ligands consist of a geometrically matching rigid polygonal core to which monovalent ligand units are attached via flexible linker polymers, closely mimicking existing experimental designs. The calculated binding affinities quantitatively agree with experimental studies for cholera toxin ( n = 5) and anthrax receptor ( n = 7) and allow to predict optimal core size and optimal linker length. Maximal binding affinity is achieved for a core that matches the receptor size and for linkers that have an equilibrium end-to-end distance that is slightly longer than the geometric separation between ligand core and receptor sites. Linkers that are longer than optimal are greatly preferable compared to shorter linkers. The angular steric restriction between ligand unit and linker polymer is shown to be a key parameter. We construct an enhancement diagram that quantifies the multivalent binding affinity compared to monovalent ligands. We conclude that multivalent ligands against influenza viral hemagglutinin ( n = 3), cholera toxin ( n = 5), and anthrax receptor ( n = 7) can outperform monovalent ligands only for a monovalent ligand affinity that exceeds a core-size dependent threshold value. Thus, multivalent drug design needs to balance core size, linker length, as well as monovalent ligand unit affinity.
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Affiliation(s)
- Susanne Liese
- Department of Physics , Freie Universität Berlin , 14195 Berlin , Germany
- Department of Mathematics , University of Oslo , 0851 Oslo , Norway
| | - Roland R Netz
- Department of Physics , Freie Universität Berlin , 14195 Berlin , Germany
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Innes-Gold SN, Morgan IL, Saleh OA. Surface-induced effects in fluctuation-based measurements of single-polymer elasticity: A direct probe of the radius of gyration. J Chem Phys 2018; 148:123314. [DOI: 10.1063/1.5009049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Sarah N. Innes-Gold
- Materials Department, University of California, Santa Barbara, California 93106, USA
| | - Ian L. Morgan
- BMSE Program, University of California, Santa Barbara, California 93106, USA
| | - Omar A. Saleh
- Materials Department, University of California, Santa Barbara, California 93106, USA
- BMSE Program, University of California, Santa Barbara, California 93106, USA
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Emilsson G, Xiong K, Sakiyama Y, Malekian B, Ahlberg Gagnér V, Schoch RL, Lim RYH, Dahlin AB. Polymer brushes in solid-state nanopores form an impenetrable entropic barrier for proteins. NANOSCALE 2018; 10:4663-4669. [PMID: 29468241 DOI: 10.1039/c7nr09432a] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Polymer brushes are widely used to prevent the adsorption of proteins, but the mechanisms by which they operate have remained heavily debated for many decades. We show conclusive evidence that a polymer brush can be a remarkably strong kinetic barrier towards proteins by using poly(ethylene glycol) grafted to the sidewalls of pores in 30 nm thin gold films. Despite consisting of about 90% water, the free coils seal apertures up to 100 nm entirely with respect to serum protein translocation, as monitored label-free through the plasmonic activity of the nanopores. The conclusions are further supported by atomic force microscopy and fluorescence microscopy. A theoretical model indicates that the brush undergoes a morphology transition to a sealing state when the ratio between the extension and the radius of curvature is approximately 0.8. The brush-sealed pores represent a new type of ultrathin filter with potential applications in bioanalytical systems.
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Affiliation(s)
- Gustav Emilsson
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg, Sweden.
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Radiom M, Maroni P, Wesolowski TA. Size extensivity of elastic properties of alkane fragments. J Mol Model 2018; 24:36. [PMID: 29313112 PMCID: PMC5758687 DOI: 10.1007/s00894-017-3572-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 12/14/2017] [Indexed: 12/01/2022]
Abstract
Using MP2, CCSD, and B3LYP methods of computational chemistry, we show length dependence in the intrinsic elastic properties of short alkane fragments. For isolated alkane fragments of finite length in the gas phase and zero temperature, the intrinsic elasticity constants are found to vary with the number of carbon atoms and its parity. From extrapolation of the elasticity constants calculations to infinite chain length, and by comparing with in-situ elasticity constant of single poly(ethylene) molecule obtained with atomic force microscopy, we estimate the softening effect of environment on the extension response of the polymer.
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Affiliation(s)
- Milad Radiom
- Department of Inorganic and Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, 1205, Geneva, Switzerland.
- School of Chemical Science and Engineering, KTH Royal Institute of Technology, Drottning Kristinas väg 51, 10044, Stockholm, Sweden.
| | - Plinio Maroni
- Department of Inorganic and Analytical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, 1205, Geneva, Switzerland
| | - Tomasz A Wesolowski
- Department of Physical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, 1205, Geneva, Switzerland
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48
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Donets S, Sommer JU. Molecular Dynamics Simulations of Strain-Induced Phase Transition of Poly(ethylene oxide) in Water. J Phys Chem B 2018; 122:392-397. [PMID: 29260568 DOI: 10.1021/acs.jpcb.7b10793] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We study the dilute aqueous solutions of poly(ethylene oxide) (PEO) oligomers that are subject to an elongating force dipole acting on both chain ends using atomistic molecular dynamics. By increasing the force, liquid-liquid demixing can be observed at room temperature far below the lower critical solution temperature. For forces above 35 pN, fibrillar nanostructures are spontaneously formed related to a decrease in hydrogen bonding between PEO and water. Most notable is a rapid decrease in the bifurcated hydrogen bonds during stretching, which can also be observed for isolated single chains. The phase-segregated structures display signs of chain ordering, but a clear signature of the crystalline order is not obtained during the simulation time, indicating a liquid-liquid phase transition induced by chain stretching. Our results indicate that the solvent quality of the aqueous solution of PEO depends on the conformational state of the chains, which is most likely related to the specific hydrogen-bond-induced solvation of PEO in water. The strain-induced demixing of PEO opens the possibility to obtain polymer fibers with low energy costs because crystallization starts via the strain-induced demixing in the extended state only.
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Affiliation(s)
- Sergii Donets
- Institute Theory of Polymers, Leibniz-Institute of Polymer Research , 01069 Dresden, Germany
| | - Jens-Uwe Sommer
- Institute Theory of Polymers, Leibniz-Institute of Polymer Research , 01069 Dresden, Germany.,Institute for Theoretical Physics, Technische Universität Dresden , 01069 Dresden, Germany
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49
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Schoch RL, Emilsson G, Dahlin AB, Lim RY. Protein exclusion is preserved by temperature sensitive PEG brushes. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.10.063] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Chudoba R, Heyda J, Dzubiella J. Temperature-Dependent Implicit-Solvent Model of Polyethylene Glycol in Aqueous Solution. J Chem Theory Comput 2017; 13:6317-6327. [DOI: 10.1021/acs.jctc.7b00560] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Richard Chudoba
- Institut
für Physik, Humboldt-Universität zu Berlin, Newtonstraße
15, D-12489 Berlin, Germany
- Institut
für Weiche Materie und Funktionale Materialen, Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, D-14109 Berlin, Germany
| | - Jan Heyda
- Department
of Physical Chemistry, University of Chemistry and Technology, Prague, Technická 5, CZ-16628 Praha 6, Czech Republic
| | - Joachim Dzubiella
- Institut
für Physik, Humboldt-Universität zu Berlin, Newtonstraße
15, D-12489 Berlin, Germany
- Institut
für Weiche Materie und Funktionale Materialen, Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, D-14109 Berlin, Germany
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