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Karger S, Miali ME, Solomonov A, Eliaz D, Varsano N, Shimanovich U. Protein Compartments Modulate Fibrillar Self-Assembly. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2308069. [PMID: 38148317 DOI: 10.1002/smll.202308069] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/04/2023] [Indexed: 12/28/2023]
Abstract
A notable feature of complex cellular environments is protein-rich compartments that are formed via liquid-liquid phase separation. Recent studies have shown that these biomolecular condensates can play both promoting and inhibitory roles in fibrillar protein self-assembly, a process that is linked to Alzheimer's, Parkinson's, Huntington's, and various prion diseases. Yet, the exact regulatory role of these condensates in protein aggregation remains unknown. By employing microfluidics to create artificial protein compartments, the self-assembly behavior of the fibrillar protein lysozyme within them can be characterized. It is observed that the volumetric parameters of protein-rich compartments can change the kinetics of protein self-assembly. Depending on the change in compartment parameters, the lysozyme fibrillation process either accelerated or decelerated. Furthermore, the results confirm that the volumetric parameters govern not only the nucleation and growth phases of the fibrillar aggregates but also affect the crosstalk between the protein-rich and protein-poor phases. The appearance of phase-separated compartments in the vicinity of natively folded protein complexes triggers their abrupt percolation into the compartments' core and further accelerates protein aggregation. Overall, the results of the study shed more light on the complex behavior and functions of protein-rich phases and, importantly, on their interaction with the surrounding environment.
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Affiliation(s)
- Shay Karger
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Marco E Miali
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Aleksei Solomonov
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Dror Eliaz
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Neta Varsano
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Ulyana Shimanovich
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
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2
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Bogdanova E, Lages S, Phan-Xuan T, Kamal MA, Terry A, Millqvist Fureby A, Kocherbitov V. Lysozyme-Sucrose Interactions in the Solid State: Glass Transition, Denaturation, and the Effect of Residual Water. Mol Pharm 2023; 20:4664-4675. [PMID: 37555640 PMCID: PMC10481396 DOI: 10.1021/acs.molpharmaceut.3c00403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 07/27/2023] [Accepted: 07/28/2023] [Indexed: 08/10/2023]
Abstract
The freeze-drying of proteins, along with excipients, offers a solution for increasing the shelf-life of protein pharmaceuticals. Using differential scanning calorimetry, thermogravimetric analysis, sorption calorimetry, and synchrotron small-angle X-ray scattering (SAXS), we have characterized the properties at low (re)hydration levels of the protein lysozyme, which was freeze-dried together with the excipient sucrose. We observe that the residual moisture content in these samples increases with the addition of lysozyme. This results from an increase in equilibrium water content with lysozyme concentration at constant water activity. Furthermore, we also observed an increase in the glass transition temperature (Tg) of the mixtures with increasing lysozyme concentration. Analysis of the heat capacity step of the mixtures indicates that lysozyme does not participate in the glass transition of the sucrose matrix; as a result, the observed increase in the Tg of the mixtures is the consequence of the confinement of the amorphous sucrose domains in the interstitial space between the lysozyme molecules. Sorption calorimetry experiments demonstrate that the hydration behavior of this formulation is similar to that of the pure amorphous sucrose, while the presence of lysozyme only shifts the sucrose transitions. SAXS analysis of amorphous lysozyme-sucrose mixtures and unfolding of lysozyme in this environment show that prior to unfolding, the size and shape of lysozyme in a solid sucrose matrix are consistent with its native state in an aqueous solution. The results obtained from our study will provide a better understanding of the low hydration behavior of protein-excipient mixtures and support the improved formulation of biologics.
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Affiliation(s)
- Ekaterina Bogdanova
- Biomedical
Science, Malmö University, Malmo SE-20506, Sweden
- Biofilms
research center for Biointerfaces, Malmo SE-20506, Sweden
| | - Sebastian Lages
- Biomedical
Science, Malmö University, Malmo SE-20506, Sweden
- Biofilms
research center for Biointerfaces, Malmo SE-20506, Sweden
- MAX
IV Laboratory, Lund University, Lund SE-22484, Sweden
| | - Tuan Phan-Xuan
- Biomedical
Science, Malmö University, Malmo SE-20506, Sweden
- Biofilms
research center for Biointerfaces, Malmo SE-20506, Sweden
- MAX
IV Laboratory, Lund University, Lund SE-22484, Sweden
| | - Md. Arif Kamal
- Biomedical
Science, Malmö University, Malmo SE-20506, Sweden
- Biofilms
research center for Biointerfaces, Malmo SE-20506, Sweden
- Division
of Physical Chemistry, Lund University, Box 124, Lund SE-221 00, Sweden
| | - Ann Terry
- MAX
IV Laboratory, Lund University, Lund SE-22484, Sweden
| | | | - Vitaly Kocherbitov
- Biomedical
Science, Malmö University, Malmo SE-20506, Sweden
- Biofilms
research center for Biointerfaces, Malmo SE-20506, Sweden
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3
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Tanouye FT, Alves JR, Spinozzi F, Itri R. Unveiling protein-protein interaction potential through Monte Carlo simulation combined with small-angle X-ray scattering. Int J Biol Macromol 2023; 248:125869. [PMID: 37473888 DOI: 10.1016/j.ijbiomac.2023.125869] [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] [Received: 03/03/2023] [Revised: 07/06/2023] [Accepted: 07/15/2023] [Indexed: 07/22/2023]
Abstract
Protein interactions are investigated under different conditions of lysozyme concentration, temperature and ionic strength by means of in-solution small angle X-Ray scattering (SAXS) experiments and Monte Carlo (MC) simulations. Initially, experimental data were analysed through a Hard-Sphere Double Yukawa (HSDY) model combined with Random Phase Approximation (RPA), a closure relationship commonly used in the literature for monodisperse systems. We realized by means of MC that the HSDY/RPA modelling fails to describe the protein-protein pair potential for moderated and dense systems at low ionic strength, mainly due to inherent distortions of the RPA approximation. Our SAXS/MC results thus show that lysozyme concentrations between 2 (diluted) and 20 mg/mL (not crowded) present similar protein-protein pair potential preserving the values of surface net charge around 7 e, protein diameter of 28 Å, decay range of attractive well potential of 3 Å and a depth of the well potential varying from 1 to 5 kBT depending on temperature and salt addition. Noteworthy, we here propose a novel method to analyse the SAXS data from interacting proteins through MC simulations, which overcomes the deficiencies presented by the use of a closure relationship. Furthermore, this new methodology of combining SAXS with MC simulations gives a step forward to investigate more complex systems as those composed of a mixture of proteins of distinct species presenting different molecular weights (and hence sizes) and surface net charges at low, moderate and very dense systems.
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Affiliation(s)
| | | | - Francesco Spinozzi
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Italy
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4
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Moron M, Al-Masoodi A, Lovato C, Reiser M, Randolph L, Surmeier G, Bolle J, Westermeier F, Sprung M, Winter R, Paulus M, Gutt C. Gelation Dynamics upon Pressure-Induced Liquid-Liquid Phase Separation in a Water-Lysozyme Solution. J Phys Chem B 2022; 126:4160-4167. [PMID: 35594491 DOI: 10.1021/acs.jpcb.2c01947] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Employing X-ray photon correlation spectroscopy, we measure the kinetics and dynamics of a pressure-induced liquid-liquid phase separation (LLPS) in a water-lysozyme solution. Scattering invariants and kinetic information provide evidence that the system reaches the phase boundary upon pressure-induced LLPS with no sign of arrest. The coarsening slows down with increasing quench depths. The g2 functions display a two-step decay with a gradually increasing nonergodicity parameter typical for gelation. We observe fast superdiffusive (γ ≥ 3/2) and slow subdiffusive (γ < 0.6) motion associated with fast viscoelastic fluctuations of the network and a slow viscous coarsening process, respectively. The dynamics age linearly with time τ ∝ tw, and we observe the onset of viscoelastic relaxation for deeper quenches. Our results suggest that the protein solution gels upon reaching the phase boundary.
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Affiliation(s)
- M Moron
- Fakultät Physik/DELTA, TU Dortmund, 44221 Dortmund, Germany
| | - A Al-Masoodi
- Department Physik, Naturwissenschaftlich-Technische Fakultät, Universität Siegen, 57068 Siegen, Germany
| | - C Lovato
- Department Physik, Naturwissenschaftlich-Technische Fakultät, Universität Siegen, 57068 Siegen, Germany
| | - M Reiser
- Department of Physics, Stockholm University, 10691 Stockholm, Sweden
| | - L Randolph
- Department Physik, Naturwissenschaftlich-Technische Fakultät, Universität Siegen, 57068 Siegen, Germany
| | - G Surmeier
- Fakultät Physik/DELTA, TU Dortmund, 44221 Dortmund, Germany
| | - J Bolle
- Fakultät Physik/DELTA, TU Dortmund, 44221 Dortmund, Germany
| | - F Westermeier
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - M Sprung
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - R Winter
- Fakultät Chemie und Chemische Biologie, Physikalische Chemie, TU Dortmund, 44227 Dortmund, Germany
| | - M Paulus
- Fakultät Physik/DELTA, TU Dortmund, 44221 Dortmund, Germany
| | - C Gutt
- Department Physik, Naturwissenschaftlich-Technische Fakultät, Universität Siegen, 57068 Siegen, Germany
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5
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Zhou X, Song R, Wang D, Fang C, Song Y, Yu R, Wang Q, Deng J. Facile preparation of functional and hybrid coatings by precipitations of polypyrrole and lysozyme via co‐assembly process. J Appl Polym Sci 2021. [DOI: 10.1002/app.50954] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Xing Zhou
- Faculty of Printing, Packaging Engineering and Digital Media Technology Xi'an University of Technology Xi'an China
- School of Mechanical and Precision Instrument Engineering Xi'an University of Technology Xi'an China
| | - Renfang Song
- Faculty of Printing, Packaging Engineering and Digital Media Technology Xi'an University of Technology Xi'an China
| | - Dong Wang
- School of Mechanical and Precision Instrument Engineering Xi'an University of Technology Xi'an China
| | - Changqing Fang
- School of Mechanical and Precision Instrument Engineering Xi'an University of Technology Xi'an China
| | - Yonghua Song
- Faculty of Printing, Packaging Engineering and Digital Media Technology Xi'an University of Technology Xi'an China
| | - Ruien Yu
- Shanxi Key Laboratory of Advanced Manufacturing Technology North University of China Taiyuan China
| | - Qiang Wang
- School of Mechanical and Precision Instrument Engineering Xi'an University of Technology Xi'an China
| | - Jingrui Deng
- Faculty of Printing, Packaging Engineering and Digital Media Technology Xi'an University of Technology Xi'an China
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6
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Camino JD, Gracia P, Cremades N. The role of water in the primary nucleation of protein amyloid aggregation. Biophys Chem 2020; 269:106520. [PMID: 33341693 DOI: 10.1016/j.bpc.2020.106520] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/26/2020] [Accepted: 11/30/2020] [Indexed: 12/18/2022]
Abstract
The understanding of the complex conformational landscape of amyloid aggregation and its modulation by relevant physicochemical and cellular factors is a prerequisite for elucidating some of the molecular basis of pathology in amyloid related diseases, and for developing and evaluating effective disease-specific therapeutics to reduce or eliminate the underlying sources of toxicity in these diseases. Interactions of proteins with solvating water have been long considered to be fundamental in mediating their function and folding; however, the relevance of water in the process of protein amyloid aggregation has been largely overlooked. Here, we provide a perspective on the role water plays in triggering primary amyloid nucleation of intrinsically disordered proteins (IDPs) based on recent experimental evidences. The initiation of amyloid aggregation likely results from the synergistic effect between both protein intermolecular interactions and the properties of the water hydration layer of the protein surface. While the self-assembly of both hydrophobic and hydrophilic IDPs would be thermodynamically favoured due to large water entropy contributions, large desolvation energy barriers are expected, particularly for the nucleation of hydrophilic IDPs. Under highly hydrating conditions, primary nucleation is slow, being facilitated by the presence of nucleation-active surfaces (heterogeneous nucleation). Under conditions of poor water activity, such as those found in the interior of protein droplets generated by liquid-liquid phase separation, however, the desolvation energy barrier is significantly reduced, and nucleation can occur very rapidly in the bulk of the solution (homogeneous nucleation), giving rise to structurally distinct amyloid polymorphs. Water, therefore, plays a key role in modulating the transition free energy of amyloid nucleation, thus governing the initiation of the process, and dictating the type of preferred primary nucleation and the type of amyloid polymorph generated, which could vary depending on the particular microenvironment that the protein molecules encounter in the cell.
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Affiliation(s)
- José D Camino
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR(CSIC), Universidad de Zaragoza, Zaragoza 50018, Spain
| | - Pablo Gracia
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR(CSIC), Universidad de Zaragoza, Zaragoza 50018, Spain
| | - Nunilo Cremades
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR(CSIC), Universidad de Zaragoza, Zaragoza 50018, Spain.
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7
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Cinar H, Fetahaj Z, Cinar S, Vernon RM, Chan HS, Winter RHA. Temperature, Hydrostatic Pressure, and Osmolyte Effects on Liquid-Liquid Phase Separation in Protein Condensates: Physical Chemistry and Biological Implications. Chemistry 2019; 25:13049-13069. [PMID: 31237369 DOI: 10.1002/chem.201902210] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/23/2019] [Indexed: 01/04/2023]
Abstract
Liquid-liquid phase separation (LLPS) of proteins and other biomolecules play a critical role in the organization of extracellular materials and membrane-less compartmentalization of intra-organismal spaces through the formation of condensates. Structural properties of such mesoscopic droplet-like states were studied by spectroscopy, microscopy, and other biophysical techniques. The temperature dependence of biomolecular LLPS has been studied extensively, indicating that phase-separated condensed states of proteins can be stabilized or destabilized by increasing temperature. In contrast, the physical and biological significance of hydrostatic pressure on LLPS is less appreciated. Summarized here are recent investigations of protein LLPS under pressures up to the kbar-regime. Strikingly, for the cases studied thus far, LLPSs of both globular proteins and intrinsically disordered proteins/regions are typically more sensitive to pressure than the folding of proteins, suggesting that organisms inhabiting the deep sea and sub-seafloor sediments, under pressures up to 1 kbar and beyond, have to mitigate this pressure-sensitivity to avoid unwanted destabilization of their functional biomolecular condensates. Interestingly, we found that trimethylamine-N-oxide (TMAO), an osmolyte upregulated in deep-sea fish, can significantly stabilize protein droplets under pressure, pointing to another adaptive advantage for increased TMAO concentrations in deep-sea organisms besides the osmolyte's stabilizing effect against protein unfolding. As life on Earth might have originated in the deep sea, pressure-dependent LLPS is pertinent to questions regarding prebiotic proto-cells. Herein, we offer a conceptual framework for rationalizing the recent experimental findings and present an outline of the basic thermodynamics of temperature-, pressure-, and osmolyte-dependent LLPS as well as a molecular-level statistical mechanics picture in terms of solvent-mediated interactions and void volumes.
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Affiliation(s)
- Hasan Cinar
- Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Strasse 4a, 44227, Dortmund, Germany
| | - Zamira Fetahaj
- Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Strasse 4a, 44227, Dortmund, Germany
| | - Süleyman Cinar
- Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Strasse 4a, 44227, Dortmund, Germany
| | - Robert M Vernon
- Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, M5G 0A4, Canada
| | - Hue Sun Chan
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Ontario, M5S 1A8, Canada.,Department of Molecular Genetics, Faculty of Medicine, University of Toronto, Ontario, M5S 1A8, Canada
| | - Roland H A Winter
- Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Strasse 4a, 44227, Dortmund, Germany
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8
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Julius K, Weine J, Gao M, Latarius J, Elbers M, Paulus M, Tolan M, Winter R. Impact of Macromolecular Crowding and Compression on Protein–Protein Interactions and Liquid–Liquid Phase Separation Phenomena. Macromolecules 2019. [DOI: 10.1021/acs.macromol.8b02476] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Karin Julius
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Jonathan Weine
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Mimi Gao
- Physical Chemistry I−Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 4a, 44227 Dortmund, Germany
| | - Jan Latarius
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Mirko Elbers
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Michael Paulus
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Metin Tolan
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Roland Winter
- Physical Chemistry I−Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 4a, 44227 Dortmund, Germany
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9
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Advances in Understanding Stimulus-Responsive Phase Behavior of Intrinsically Disordered Protein Polymers. J Mol Biol 2018; 430:4619-4635. [DOI: 10.1016/j.jmb.2018.06.031] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/12/2018] [Accepted: 06/18/2018] [Indexed: 12/20/2022]
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10
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Blanco MA, Hatch HW, Curtis JE, Shen VK. A methodology to calculate small-angle scattering profiles of macromolecular solutions from molecular simulations in the grand-canonical ensemble. J Chem Phys 2018; 149:084203. [PMID: 30193476 DOI: 10.1063/1.5029274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The theoretical framework to evaluate small-angle scattering (SAS) profiles for multi-component macromolecular solutions is re-examined from the standpoint of molecular simulations in the grand-canonical ensemble, where the chemical potentials of all species in solution are fixed. This statistical mechanical ensemble resembles more closely scattering experiments, capturing concentration fluctuations that arise from the exchange of molecules between the scattering volume and the bulk solution. The resulting grand-canonical expression relates scattering intensities to the different intra- and intermolecular pair distribution functions, as well as to the distribution of molecular concentrations on the scattering volume. This formulation represents a generalized expression that encompasses most of the existing methods to evaluate SAS profiles from molecular simulations. The grand-canonical SAS methodology is probed for a series of different implicit-solvent, homogeneous systems at conditions ranging from dilute to concentrated. These systems consist of spherical colloids, dumbbell particles, and highly flexible polymer chains. Comparison of the resulting SAS curves against classical methodologies based on either theoretical approaches or canonical simulations (i.e., at a fixed number of molecules) shows equivalence between the different scattering intensities so long as interactions between molecules are net repulsive or weakly attractive. On the other hand, for strongly attractive interactions, grand-canonical SAS profiles deviate in the low- and intermediate-q range from those calculated in a canonical ensemble. Such differences are due to the distribution of molecules becoming asymmetric, which yields a higher contribution from configurations with molecular concentrations larger than the nominal value. Additionally, for flexible systems, explicit discrimination between intra- and inter-molecular SAS contributions permits the implementation of model-free, structural analysis such as Guinier's plots at high molecular concentrations, beyond what the traditional limits are for such analysis.
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Affiliation(s)
- Marco A Blanco
- Chemical Informatics Group, Chemical Sciences Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Harold W Hatch
- Chemical Informatics Group, Chemical Sciences Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Joseph E Curtis
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Vincent K Shen
- Chemical Informatics Group, Chemical Sciences Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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11
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Cinar H, Cinar S, Chan HS, Winter R. Pressure-Induced Dissolution and Reentrant Formation of Condensed, Liquid-Liquid Phase-Separated Elastomeric α-Elastin. Chemistry 2018; 24:8286-8291. [PMID: 29738068 DOI: 10.1002/chem.201801643] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 05/07/2018] [Indexed: 02/05/2023]
Abstract
We investigated the combined effects of temperature and pressure on liquid-liquid phase separation (LLPS) phenomena of α-elastin up to the multi-kbar regime. FT-IR spectroscopy, CD, UV/Vis absorption, phase-contrast light and fluorescence microscopy techniques were employed to reveal structural changes and mesoscopic phase states of the system. A novel pressure-induced reentrant LLPS was observed in the intermediate temperature range. A molecular-level picture, in particular on the role of hydrophobic interactions, hydration, and void volume in controlling LLPS phenomena is presented. The potential role of the LLPS phenomena in the development of early cellular compartmentalization is discussed, which might have started in the deep sea, where pressures up to the kbar level are encountered.
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Affiliation(s)
- Hasan Cinar
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Strasse 4a, 44227, Dortmund, Germany
| | - Süleyman Cinar
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Strasse 4a, 44227, Dortmund, Germany
| | - Hue Sun Chan
- Departments of Biochemistry and Molecular Genetics, Faculty of Medicine, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Strasse 4a, 44227, Dortmund, Germany
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12
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Möller J, Léonardon J, Gorini J, Dattani R, Narayanan T. A sub-ms pressure jump setup for time-resolved X-ray scattering. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:125116. [PMID: 28040915 DOI: 10.1063/1.4972296] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present a new experimental setup for time-resolved solution small-angle X-ray scattering (SAXS) studies of kinetic processes induced by sub-ms hydrostatic pressure jumps. It is based on a high-force piezo-stack actuator, with which the volume of the sample can be dynamically compressed. The presented setup has been designed and optimized for SAXS experiments with absolute pressures of up to 1000 bars, using transparent diamond windows and an easy-to-change sample capillary. The pressure in the cell can be changed in less than 1 ms, which is about an order of magnitude faster jump than previously obtained by dynamic pressure setups for SAXS. An additional temperature control offers the possibility for automated mapping of p-T phase diagrams. Here we present the technical specifications and first experimental data taken together with a preview of new research opportunities enabled by this setup.
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