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Razzokov J, Fazliev S, Makhkamov M, Marimuthu P, Baev A, Kurganov E. Effect of Electric Field on α-Synuclein Fibrils: Revealed by Molecular Dynamics Simulations. Int J Mol Sci 2023; 24:ijms24076312. [PMID: 37047286 PMCID: PMC10094641 DOI: 10.3390/ijms24076312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/24/2023] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
The self-association of amylogenic proteins to the fibril form is considered a pivotal factor in the pathogenesis of neurodegenerative diseases, including Parkinson’s disease (PD). PD causes unintended or uncontrollable movements in its common symptoms. α-synuclein is the major cause of PD development and thus has been the main target of numerous studies to suppress and sequester its expression or effectively degrade it. Nonetheless, to date, there are no efficient and proven ways to prevent pathological protein aggregation. Recent investigations proposed applying an external electric field to interrupt the fibrils. This method is a non-invasive approach that has a certain benefit over others. We performed molecular dynamics (MD) simulations by applying an electric field on highly toxic fibrils of α-synuclein to gain a molecular-level insight into fibril disruption mechanisms. The results revealed that the applied external electric field induces substantial changes in the conformation of the α-synuclein fibrils. Furthermore, we show the threshold value for electric field strength required to completely disrupt the α-synuclein fibrils by opening the hydrophobic core of the fibril. Thus, our findings might serve as a valuable foundation to better understand molecular-level mechanisms of the α-synuclein fibrils disaggregation process under an applied external electric field.
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Affiliation(s)
- Jamoliddin Razzokov
- Institute of Fundamental and Applied Research, National Research University TIIAME, Kori Niyoziy 39, Tashkent 100000, Uzbekistan
- R&D Center, New Uzbekistan University, Mustaqillik Avenue 54, Tashkent 100007, Uzbekistan
- Institute of Material Sciences, Academy of Sciences, Chingiz Aytmatov 2b, Tashkent 100084, Uzbekistan
- Department of Physics, National University of Uzbekistan, Universitet 4, Tashkent 100174, Uzbekistan
- Correspondence: ; Tel.: +998-90-116-23-20
| | - Sunnatullo Fazliev
- Max Planck School Matter to Life, Jahnstrasse 29, 69120 Heidelberg, Germany
- Faculty of Engineering Sciences, Heidelberg University, Im Neuenheimer Feld 205, 69120 Heidelberg, Germany
| | - Mukhriddin Makhkamov
- Laboratory of Experimental Biophysics, Centre for Advanced Technologies, Tashkent 100174, Uzbekistan
| | - Parthiban Marimuthu
- Pharmaceutical Science Laboratory (PSL–Pharmacy) and Structural Bioinformatics Laboratory (SBL–Biochemistry), Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland
| | - Artyom Baev
- Laboratory of Experimental Biophysics, Centre for Advanced Technologies, Tashkent 100174, Uzbekistan
- Department of Biophysics, Biological Faculty, National University of Uzbekistan, Universitet 4, Tashkent 100174, Uzbekistan
| | - Erkin Kurganov
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
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de Bruijn R, Wielstra PCM, Calcines-Cruz C, van Waveren T, Hernandez-Garcia A, van der Schoot P. A kinetic model for the impact of packaging signal mimics on genome encapsulation. Biophys J 2022; 121:2583-2599. [PMID: 35642255 DOI: 10.1016/j.bpj.2022.05.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 05/09/2022] [Accepted: 05/24/2022] [Indexed: 11/18/2022] Open
Abstract
Inspired by recent experiments on the spontaneous assembly of virus-like particles from a solution containing a synthetic coat protein and double-stranded DNA, we put forward a kinetic model that has as main ingredients a stochastic nucleation and a deterministic growth process. The efficiency and rate of DNA packaging strongly increase after tiling the DNA with CRISPR-Cas proteins at predesignated locations, mimicking assembly signals in viruses. Our model shows that treating these proteins as nucleation-inducing diffusion barriers is sufficient to explain the experimentally observed increase in encapsulation efficiency, but only if the nucleation rate is sufficiently high. We find an optimum in the encapsulation kinetics for conditions where the number of packaging signal mimics is equal to the number of nucleation events that can occur during the time required to fully encapsulate the DNA template, presuming that the nucleation events can only take place adjacent to a packaging signal. Our theory is in satisfactory agreement with the available experimental data.
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Affiliation(s)
- René de Bruijn
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, the Netherlands; Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands.
| | | | - Carlos Calcines-Cruz
- Department of Chemistry of Biomacromolecules, Institute of Chemistry, National Autonomous University of Mexico, Mexico City, Mexico
| | - Tom van Waveren
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Armando Hernandez-Garcia
- Department of Chemistry of Biomacromolecules, Institute of Chemistry, National Autonomous University of Mexico, Mexico City, Mexico
| | - Paul van der Schoot
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, the Netherlands
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3
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Vargas EC, Stuart MAC, de Vries R, Hernandez‐Garcia A. Template‐Free Self‐Assembly of Artificial De Novo Viral Coat Proteins into Nanorods: Effects of Sequence, Concentration, and Temperature. Chemistry 2019; 25:11058-11065. [DOI: 10.1002/chem.201901486] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Indexed: 01/21/2023]
Affiliation(s)
- Ernesto Cazares Vargas
- Institute of ChemistryDepartment of Biomacromolecules ChemistryNational Autonomous University of Mexico Circuito Exterior, Ciudad Universitaria, Coyoacán, C.P. 04510 Mexico City Mexico
| | - Martien A. Cohen Stuart
- Laboratory of Physical Chemistry and Soft MatterWageningen University, Helix, 124 Stippeneng 4 6708 WE Wageningen The Netherlands
| | - Renko de Vries
- Laboratory of Physical Chemistry and Soft MatterWageningen University, Helix, 124 Stippeneng 4 6708 WE Wageningen The Netherlands
| | - Armando Hernandez‐Garcia
- Institute of ChemistryDepartment of Biomacromolecules ChemistryNational Autonomous University of Mexico Circuito Exterior, Ciudad Universitaria, Coyoacán, C.P. 04510 Mexico City Mexico
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Razzokov J, Naderi S, van der Schoot P. Nanoscale insight into silk-like protein self-assembly: effect of design and number of repeat units. Phys Biol 2018; 15:066010. [PMID: 30124438 DOI: 10.1088/1478-3975/aadb5e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
By means of replica exchange molecular dynamics simulations we investigate how the length of a silk-like, alternating diblock oligopeptide influences its secondary and quaternary structure. We carry out simulations for two protein sizes consisting of three and five blocks, and study the stability of a single protein, a dimer, a trimer and a tetramer. Initial configurations of our simulations are β-roll and β-sheet structures. We find that for the triblock the secondary and quaternary structures upto and including the tetramer are unstable: the proteins melt into random coil structures and the aggregates disassemble either completely or partially. We attribute this to the competition between conformational entropy of the proteins and the formation of hydrogen bonds and hydrophobic interactions between proteins. This is confirmed by our simulations on the pentablock proteins, where we find that, as the number of monomers in the aggregate increases, individual monomers form more hydrogen bonds whereas their solvent accessible surface area decreases. For the pentablock β-sheet protein, the monomer and the dimer melt as well, although for the β-roll protein only the monomer melts. For both trimers and tetramers remain stable. Apparently, for these the entropy loss of forming β-rolls and β-sheets is compensated for in the free-energy gain due to the hydrogen-bonding and hydrophobic interactions. We also find that the middle monomers in the trimers and tetramers are conformationally much more stable than the ones on the top and the bottom. Interestingly, the latter are more stable on the tetramer than on the trimer, suggesting that as the number of monomers increases protein-protein interactions cooperatively stabilize the assembly. According to our simulations, the β-roll and β-sheet aggregates must be approximately equally stable.
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Affiliation(s)
- Jamoliddin Razzokov
- Department of Chemistry, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium. Faculteit Technische Natuurkunde, Technische Universiteit Eindhoven, Postbus 513, 5600 MB Eindhoven, Netherlands
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5
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Bu B, Tong X, Li D, Hu Y, He W, Zhao C, Hu R, Li X, Shao Y, Liu C, Zhao Q, Ji B, Diao J. N-Terminal Acetylation Preserves α-Synuclein from Oligomerization by Blocking Intermolecular Hydrogen Bonds. ACS Chem Neurosci 2017; 8:2145-2151. [PMID: 28741930 DOI: 10.1021/acschemneuro.7b00250] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The abnormal aggregation of α-synuclein (α-Syn) is closely associated with Parkinson's disease. Different post-translational modifications of α-Syn have been identified and contribute distinctly in α-Syn aggregation and cytotoxicity. Recently, α-Syn was reported to be N-terminally acetylated in cells, yet the functional implication of this modification, especially in α-Syn oligomerization, remains unclear. By using a solid-state nanopore system, we found that N-terminal acetylation can significantly decrease α-Syn oligomerization. Replica-exchange molecular dynamics simulations further revealed that addition of an acetyl group at the N-terminus disrupts intermolecular hydrogen bonds, which slows down the initial α-Syn oligomerization. Our finding highlights the essential role of N-terminal acetylation of α-Syn in preserving its native conformation against pathological aggregation.
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Affiliation(s)
- Bing Bu
- Biomechanics
and Biomaterials Laboratory, Department of Applied Mechanics, Beijing Institute of Technology, Beijing 100081, China
| | - Xin Tong
- State
Key Laboratory for Mesoscopic Physics and Electron Microscopy Laboratory,
School of Physics, Peking University, Beijing 100871, China
| | - Dechang Li
- Biomechanics
and Biomaterials Laboratory, Department of Applied Mechanics, Beijing Institute of Technology, Beijing 100081, China
| | - Yachong Hu
- Department
of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, United States
- Key
Laboratory of Biomedical Information Engineering of the Ministry of
Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710049, China
| | - Wangxiao He
- Key
Laboratory of Biomedical Information Engineering of the Ministry of
Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710049, China
| | - Chunyu Zhao
- Interdisciplinary
Research Center on Biology and Chemistry, Shanghai Institute of Organic
Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Rui Hu
- State
Key Laboratory for Mesoscopic Physics and Electron Microscopy Laboratory,
School of Physics, Peking University, Beijing 100871, China
| | - Xiaoqing Li
- State
Key Laboratory for Mesoscopic Physics and Electron Microscopy Laboratory,
School of Physics, Peking University, Beijing 100871, China
| | - Yongping Shao
- Key
Laboratory of Biomedical Information Engineering of the Ministry of
Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710049, China
| | - Cong Liu
- Interdisciplinary
Research Center on Biology and Chemistry, Shanghai Institute of Organic
Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Qing Zhao
- State
Key Laboratory for Mesoscopic Physics and Electron Microscopy Laboratory,
School of Physics, Peking University, Beijing 100871, China
| | - Baohua Ji
- Biomechanics
and Biomaterials Laboratory, Department of Applied Mechanics, Beijing Institute of Technology, Beijing 100081, China
| | - Jiajie Diao
- Department
of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, United States
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6
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Zhao B, Cohen Stuart MA, Hall CK. Navigating in foldonia: Using accelerated molecular dynamics to explore stability, unfolding and self-healing of the β-solenoid structure formed by a silk-like polypeptide. PLoS Comput Biol 2017; 13:e1005446. [PMID: 28329017 PMCID: PMC5388506 DOI: 10.1371/journal.pcbi.1005446] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 04/11/2017] [Accepted: 03/08/2017] [Indexed: 11/22/2022] Open
Abstract
The β roll molecules with sequence (GAGAGAGQ)10 stack via hydrogen bonding to form fibrils which have been themselves been used to make viral capsids of DNA strands, supramolecular nanotapes and pH-responsive gels. Accelerated molecular dynamics (aMD) simulations are used to investigate the unfolding of a stack of two β roll molecules, (GAGAGAGQ)10, to shed light on the folding mechanism by which silk-inspired polypeptides form fibrils and to identify the dominant forces that keep the silk-inspired polypeptide in a β roll configuration. Our study shows that a molecule in a stack of two β roll molecules unfolds in a step-wise fashion mainly from the C terminal. The bottom template is found to play an important role in stabilizing the β roll structure of the molecule on top by strengthening the hydrogen bonds in the layer that it contacts. Vertical hydrogen bonds within the β roll structure are considerably weaker than lateral hydrogen bonds, signifying the importance of lateral hydrogen bonds in stabilizing the β roll structure. Finally, an intermediate structure was found containing a β hairpin and an anti-parallel β sheet consisting of strands from the top and bottom molecules, revealing the self-healing ability of the β roll stack.
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Affiliation(s)
- Binwu Zhao
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, United States
| | - Martien A. Cohen Stuart
- Laboratory of Physical Chemistry & Colloid Science, Wageningen University, NL, Wageningen, The Netherlands
| | - Carol K. Hall
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, United States
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7
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Włodarczyk-Biegun MK, Werten MWT, Posadowska U, Storm IM, de Wolf FA, van den Beucken JJJP, Leeuwenburgh SCG, Cohen Stuart MA, Kamperman M. Nanofibrillar hydrogel scaffolds from recombinant protein-based polymers with integrin- and proteoglycan-binding domains. J Biomed Mater Res A 2016; 104:3082-3092. [PMID: 27449385 PMCID: PMC5129582 DOI: 10.1002/jbm.a.35839] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 06/23/2016] [Accepted: 07/21/2016] [Indexed: 01/24/2023]
Abstract
This study describes the design, production, and testing of functionalized variants of a recombinant protein‐based polymer that forms nanofibrillar hydrogels with self‐healing properties. With a view to bone tissue engineering applications, we equipped these variants with N‐terminal extensions containing either (1) integrin‐binding (RGD) or (2) less commonly studied proteoglycan‐binding (KRSR) cell‐adhesive motifs. The polymers were efficiently produced as secreted proteins using the yeast Pichia pastoris and were essentially monodisperse. The pH‐responsive protein‐based polymers are soluble at low pH and self‐assemble into supramolecular fibrils and hydrogels at physiological pH. By mixing functionalized and nonfunctionalized proteins in different ratios, and adjusting pH, hydrogel scaffolds with the same protein concentration but varying content of the two types of cell‐adhesive motifs were readily obtained. The scaffolds were used for the two‐dimensional culture of MG‐63 osteoblastic cells. RGD domains had a slightly stronger effect than KRSR domains on adhesion, activity, and spreading. However, scaffolds featuring both functional domains revealed a clear synergistic effect on cell metabolic activity and spreading, and provided the highest final degree of cell confluency. The mixed functionalized hydrogels presented here thus allowed to tailor the osteoblastic cell response, offering prospects for their further development as scaffolds for bone regeneration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 3082–3092, 2016.
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Affiliation(s)
| | - Marc W T Werten
- Wageningen UR Food & Biobased Research, Bornse Weilanden 9, NL-6708 WG Wageningen, The Netherlands.
| | - Urszula Posadowska
- Physical Chemistry and Soft Matter, Wageningen University, Stippeneng 4, NL-6708 WE Wageningen, The Netherlands.,Faculty of Materials Science and Ceramics, Department of Biomaterials, AGH University of Science and Technology, Al. A. Mickiewicza 30, Krakow, 30-059, Poland
| | - Ingeborg M Storm
- Physical Chemistry and Soft Matter, Wageningen University, Stippeneng 4, NL-6708 WE Wageningen, The Netherlands
| | - Frits A de Wolf
- Wageningen UR Food & Biobased Research, Bornse Weilanden 9, NL-6708 WG Wageningen, The Netherlands
| | | | - Sander C G Leeuwenburgh
- Department of Biomaterials, Radboudumc, Philips Van Leydenlaan 25, NL-6525 EX Nijmegen, The Netherlands
| | - Martien A Cohen Stuart
- Physical Chemistry and Soft Matter, Wageningen University, Stippeneng 4, NL-6708 WE Wageningen, The Netherlands
| | - Marleen Kamperman
- Physical Chemistry and Soft Matter, Wageningen University, Stippeneng 4, NL-6708 WE Wageningen, The Netherlands
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8
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Włodarczyk-Biegun MK, Farbod K, Werten MWT, Slingerland CJ, de Wolf FA, van den Beucken JJJP, Leeuwenburgh SCG, Cohen Stuart MA, Kamperman M. Fibrous Hydrogels for Cell Encapsulation: A Modular and Supramolecular Approach. PLoS One 2016; 11:e0155625. [PMID: 27223105 PMCID: PMC4880210 DOI: 10.1371/journal.pone.0155625] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/01/2016] [Indexed: 12/25/2022] Open
Abstract
Artificial 3-dimensional (3D) cell culture systems, which mimic the extracellular matrix (ECM), hold great potential as models to study cellular processes under controlled conditions. The natural ECM is a 3D structure composed of a fibrous hydrogel that provides both mechanical and biochemical cues to instruct cell behavior. Here we present an ECM-mimicking genetically engineered protein-based hydrogel as a 3D cell culture system that combines several key features: (1) Mild and straightforward encapsulation meters (1) ease of ut I am not so sure.encapsulation of the cells, without the need of an external crosslinker. (2) Supramolecular assembly resulting in a fibrous architecture that recapitulates some of the unique mechanical characteristics of the ECM, i.e. strain-stiffening and self-healing behavior. (3) A modular approach allowing controlled incorporation of the biochemical cue density (integrin binding RGD domains). We tested the gels by encapsulating MG-63 osteoblastic cells and found that encapsulated cells not only respond to higher RGD density, but also to overall gel concentration. Cells in 1% and 2% (weight fraction) protein gels showed spreading and proliferation, provided a relative RGD density of at least 50%. In contrast, in 4% gels very little spreading and proliferation occurred, even for a relative RGD density of 100%. The independent control over both mechanical and biochemical cues obtained in this modular approach renders our hydrogels suitable to study cellular responses under highly defined conditions.
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Affiliation(s)
| | - Kambiz Farbod
- Department of Biomaterials, Radboud University Medical Center, Nijmegen, The Netherlands
| | | | - Cornelis J. Slingerland
- Physical Chemistry and Soft Matter, Wageningen University & Research, Wageningen, The Netherlands
| | - Frits A. de Wolf
- Wageningen UR Food & Biobased Research, Wageningen, The Netherlands
| | | | | | - Martien A. Cohen Stuart
- Physical Chemistry and Soft Matter, Wageningen University & Research, Wageningen, The Netherlands
| | - Marleen Kamperman
- Physical Chemistry and Soft Matter, Wageningen University & Research, Wageningen, The Netherlands
- * E-mail:
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9
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Włodarczyk-Biegun MK, Slingerland CJ, Werten MWT, van Hees IA, de Wolf FA, de Vries R, Stuart MAC, Kamperman M. Heparin as a Bundler in a Self-Assembled Fibrous Network of Functionalized Protein-Based Polymers. Biomacromolecules 2016; 17:2063-72. [DOI: 10.1021/acs.biomac.6b00276] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Cornelis J. Slingerland
- Physical
Chemistry and Soft Matter, Wageningen University and Research, Wageningen, The Netherlands
| | - Marc W. T. Werten
- Wageningen UR
Food and Biobased Research, Wageningen, The Netherlands
| | - Ilse A. van Hees
- Physical
Chemistry and Soft Matter, Wageningen University and Research, Wageningen, The Netherlands
| | - Frits A. de Wolf
- Wageningen UR
Food and Biobased Research, Wageningen, The Netherlands
| | - Renko de Vries
- Physical
Chemistry and Soft Matter, Wageningen University and Research, Wageningen, The Netherlands
| | - Martien A. Cohen Stuart
- Physical
Chemistry and Soft Matter, Wageningen University and Research, Wageningen, The Netherlands
| | - Marleen Kamperman
- Physical
Chemistry and Soft Matter, Wageningen University and Research, Wageningen, The Netherlands
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10
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Stegen J, van der Schoot P. Self-crowding induced phase separation in protein dispersions. J Chem Phys 2016; 142:244901. [PMID: 26133451 DOI: 10.1063/1.4922927] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The coupling between protein conformation, molecular volume, and solution phase behaviour is studied theoretically for a two-state, coarse-grained protein model in which protein molecules can reversibly switch between a native and a non-native excited state. In the model, native and non-native conformers are represented by perfect spheres with different hard-core diameters. We presume the larger, non-native species to attract each other through some unspecified potential. We find that at low concentrations the native state is stabilised energetically and that at high concentrations the native state is again stabilised but this time by self-crowding, i.e., a lack of free volume. These two regimes are separated by two first-order transitions from a region where the non-native conformational state is prevalent, stabilised by attractive interactions between the proteins. The calculated phase diagram is very sensitive to even quite small differences in particle volumes and has unusual features, including the loss of a critical point if the size difference is sufficiently large.
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Affiliation(s)
- J Stegen
- Applied Physics, Eindhoven University of Technology, Eindhoven 5600 MB, The Netherlands
| | - P van der Schoot
- Applied Physics, Eindhoven University of Technology, Eindhoven 5600 MB, The Netherlands
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