1
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Ota C, Konishi T, Tanaka SI, Takano K. Induced Circular Dichroism Analysis of Thermally Induced Conformational Changes on Protein Binding Sites Under a Crowding Environment. Chemphyschem 2024; 25:e202300593. [PMID: 37845184 DOI: 10.1002/cphc.202300593] [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: 08/20/2023] [Revised: 10/15/2023] [Accepted: 10/16/2023] [Indexed: 10/18/2023]
Abstract
Protein-ligand interactions in crowded cellular environments play a crucial role in biological functions. The crowded environment can perturb the overall protein structure and local conformation, thereby influencing the binding pathway of protein-ligand reactions within the cellular milieu. Therefore, a detailed understanding of the local conformation is crucial for elucidating the intricacies of protein-ligand interactions in crowded cellular environments. In this study, we investigated the feasibility of induced circular dichroism (ICD) using 8-anilinonaphthalene-1-sulfonic acid (ANS) for local conformational analysis at the binding site in a crowding environment. Bovine serum albumin (BSA) concentration-dependent measurements were performed to assess the feasibility of ANS-ICD for analyzing protein interior binding sites. The results showed distinct changes in the ANS-ICD spectra of BSA solutions, indicating their potential for analyzing the internal conformation of proteins. Moreover, temperature-dependent measurements were performed in dilute and crowding environments, revealing distinct denaturation pathways of BSA binding sites. Principal component analysis of ANS-ICD spectral changes revealed lower temperature pre-denaturation in the crowded solution than that in the diluted solution, suggesting destabilization of binding sites owing to self-crowding repulsive interactions. The established ANS-ICD method can provide valuable conformational insights into protein-ligand interactions in crowded cellular environments.
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Affiliation(s)
- Chikashi Ota
- College of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan
| | - Tomoya Konishi
- Department of Biomolecular Chemistry, Kyoto Prefectural University, Sakyo-ku, Kyoto, 606-8522, Japan
| | - Shun-Ichi Tanaka
- Department of Biomolecular Chemistry, Kyoto Prefectural University, Sakyo-ku, Kyoto, 606-8522, Japan
| | - Kazufumi Takano
- Department of Biomolecular Chemistry, Kyoto Prefectural University, Sakyo-ku, Kyoto, 606-8522, Japan
- Kazufumi Takano - Department of Biomolecular Chemistry, Kyoto Prefectural University, Sakyo-ku, Kyoto, 606-8522, Japan
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2
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Peters J, Oliva R, Caliò A, Oger P, Winter R. Effects of Crowding and Cosolutes on Biomolecular Function at Extreme Environmental Conditions. Chem Rev 2023; 123:13441-13488. [PMID: 37943516 DOI: 10.1021/acs.chemrev.3c00432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
The extent of the effect of cellular crowding and cosolutes on the functioning of proteins and cells is manifold and includes the stabilization of the biomolecular systems, the excluded volume effect, and the modulation of molecular dynamics. Simultaneously, it is becoming increasingly clear how important it is to take the environment into account if we are to shed light on biological function under various external conditions. Many biosystems thrive under extreme conditions, including the deep sea and subseafloor crust, and can take advantage of some of the effects of crowding. These relationships have been studied in recent years using various biophysical techniques, including neutron and X-ray scattering, calorimetry, FTIR, UV-vis and fluorescence spectroscopies. Combining knowledge of the structure and conformational dynamics of biomolecules under extreme conditions, such as temperature, high hydrostatic pressure, and high salinity, we highlight the importance of considering all results in the context of the environment. Here we discuss crowding and cosolute effects on proteins, nucleic acids, membranes, and live cells and explain how it is possible to experimentally separate crowding-induced effects from other influences. Such findings will contribute to a better understanding of the homeoviscous adaptation of organisms and the limits of life in general.
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Affiliation(s)
- Judith Peters
- Univ. Grenoble Alpes, CNRS, LiPhy, 140 rue de la physique, 38400 St Martin d'Hères, France
- Institut Laue Langevin, 71 avenue des Martyrs, 38000 Grenoble, France
- Institut Universitaire de France, 75005 Paris, France
| | - Rosario Oliva
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, 80126 Naples, Italy
| | - Antonino Caliò
- European Synchrotron Radiation Facility, 71 avenue des Martyrs, 38000 Grenoble, France
| | - Philippe Oger
- INSA Lyon, Universite Claude Bernard Lyon1, CNRS, UMR5240, 69621 Villeurbanne, France
| | - Roland Winter
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, Dortmund, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany
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3
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Kharmyssov C, Sekerbayev K, Nurekeyev Z, Gaipov A, Utegulov ZN. Mechano-Chemistry across Phase Transitions in Heated Albumin Protein Solutions. Polymers (Basel) 2023; 15:polym15092039. [PMID: 37177189 PMCID: PMC10180835 DOI: 10.3390/polym15092039] [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: 02/16/2023] [Revised: 04/02/2023] [Accepted: 04/14/2023] [Indexed: 05/15/2023] Open
Abstract
The presence of certain proteins in biofluids such as synovial fluid, blood plasma, and saliva gives these fluids non-Newtonian viscoelastic properties. The amount of these protein macromolecules in biofluids is an important biomarker for the diagnosis of various health conditions, including Alzheimer's disease, cardiovascular disorders, and joint quality. However, existing technologies for measuring the behavior of macromolecules in biofluids have limitations, such as long turnaround times, complex protocols, and insufficient sensitivity. To address these issues, we propose non-contact, optical Brillouin and Raman spectroscopy to assess the viscoelasticity and chemistry of non-Newtonian solutions, respectively, at different temperatures in several minutes. In this work, bovine and human serum albumin solution-based biopolymers were studied to obtain both their collective dynamics and molecular chemical evolution across heat-driven phase transitions at various protein concentrations. The observed phase transitions at elevated temperatures could be fully delayed in heated biopolymers by appropriately raising the level of protein concentration. The non-contact optical monitoring of viscoelastic and chemical property evolution could represent novel potential mechano-chemical biomarkers for disease diagnosis and subsequent treatment applications, including hyperthermia.
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Affiliation(s)
- Chingis Kharmyssov
- Department of Physics, School of Sciences and Humanities, Nazarbayev University, 010000 Astana, Kazakhstan
- Science Department, Astana IT University, 010000 Astana, Kazakhstan
| | - Kairolla Sekerbayev
- Department of Physics, School of Sciences and Humanities, Nazarbayev University, 010000 Astana, Kazakhstan
| | - Zhangatay Nurekeyev
- Department of Physics, School of Sciences and Humanities, Nazarbayev University, 010000 Astana, Kazakhstan
- Institute for Experimental Physics, Hamburg University, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Abduzhappar Gaipov
- Department of Medicine, School of Medicine, Nazarbayev University, 010000 Astana, Kazakhstan
| | - Zhandos N Utegulov
- Department of Physics, School of Sciences and Humanities, Nazarbayev University, 010000 Astana, Kazakhstan
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4
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Di Bari D, Timr S, Guiral M, Giudici-Orticoni MT, Seydel T, Beck C, Petrillo C, Derreumaux P, Melchionna S, Sterpone F, Peters J, Paciaroni A. Diffusive Dynamics of Bacterial Proteome as a Proxy of Cell Death. ACS CENTRAL SCIENCE 2023; 9:93-102. [PMID: 36712493 PMCID: PMC9881203 DOI: 10.1021/acscentsci.2c01078] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Indexed: 05/30/2023]
Abstract
Temperature variations have a big impact on bacterial metabolism and death, yet an exhaustive molecular picture of these processes is still missing. For instance, whether thermal death is determined by the deterioration of the whole or a specific part of the proteome is hotly debated. Here, by monitoring the proteome dynamics of E. coli, we clearly show that only a minor fraction of the proteome unfolds at the cell death. First, we prove that the dynamical state of the E. coli proteome is an excellent proxy for temperature-dependent bacterial metabolism and death. The proteome diffusive dynamics peaks at about the bacterial optimal growth temperature, then a dramatic dynamical slowdown is observed that starts just below the cell's death temperature. Next, we show that this slowdown is caused by the unfolding of just a small fraction of proteins that establish an entangling interprotein network, dominated by hydrophobic interactions, across the cytoplasm. Finally, the deduced progress of the proteome unfolding and its diffusive dynamics are both key to correctly reproduce the E. coli growth rate.
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Affiliation(s)
- Daniele Di Bari
- Università
degli Studi di Perugia, Dipartimento di
Fisica e Geologia, Via
A. Pascoli, 06123Perugia PG, Italy
- Université
Grenoble Alpes, CNRS, Laboratoire Interdisciplinaire de Physique, 38400Saint-Martin-d’Héres, France
- Institut
Laue-Langevin, 38000Grenoble, France
| | - Stepan Timr
- Laboratoire
de Biochimie Théorique (UPR9080), CNRS, Université de Paris Cité, 13 Rue Pierre et Marie Curie, 75005Paris, France
- Institut
de Biologie Physico-Chimique, Fondation Edmond de Rothschild, 13 Rue Pierre et Marie Curie, 75005Paris, France
- J.
Heyrovský
Institute of Physical Chemistry, Czech Academy
of Sciences, 182 23Prague 8, Czechia
| | - Marianne Guiral
- Laboratoire
de Bioénergétique et Ingénierie des Protéines, BIP, CNRS, Aix-Marseille Université, 13400Marseille, France
| | | | - Tilo Seydel
- Institut
Laue-Langevin, 38000Grenoble, France
| | | | - Caterina Petrillo
- Università
degli Studi di Perugia, Dipartimento di
Fisica e Geologia, Via
A. Pascoli, 06123Perugia PG, Italy
| | - Philippe Derreumaux
- Laboratoire
de Biochimie Théorique (UPR9080), CNRS, Université de Paris Cité, 13 Rue Pierre et Marie Curie, 75005Paris, France
- Institut
de Biologie Physico-Chimique, Fondation Edmond de Rothschild, 13 Rue Pierre et Marie Curie, 75005Paris, France
- Institut Universitaire de France, 75005Paris, France
| | - Simone Melchionna
- ISC-CNR,
Dipartimento di Fisica, Università
Sapienza, 00185Rome, Italy
- Lexma
Technology1337 Massachusetts
Avenue, Arlington, Massachusetts02476, United States
| | - Fabio Sterpone
- Laboratoire
de Biochimie Théorique (UPR9080), CNRS, Université de Paris Cité, 13 Rue Pierre et Marie Curie, 75005Paris, France
- Institut
de Biologie Physico-Chimique, Fondation Edmond de Rothschild, 13 Rue Pierre et Marie Curie, 75005Paris, France
| | - Judith Peters
- Université
Grenoble Alpes, CNRS, Laboratoire Interdisciplinaire de Physique, 38400Saint-Martin-d’Héres, France
- Institut
Laue-Langevin, 38000Grenoble, France
- Institut Universitaire de France, 75005Paris, France
| | - Alessandro Paciaroni
- Università
degli Studi di Perugia, Dipartimento di
Fisica e Geologia, Via
A. Pascoli, 06123Perugia PG, Italy
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5
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Golub M, Moldenhauer M, Schmitt FJ, Lohstroh W, Friedrich T, Pieper J. Light-Induced Conformational Flexibility of the Orange Carotenoid Protein Studied by Quasielastic Neutron Scattering with In Situ Illumination. J Phys Chem Lett 2023; 14:295-301. [PMID: 36599148 DOI: 10.1021/acs.jpclett.2c03198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The orange carotenoid protein plays a vital role in the photoprotection of cyanobacteria and exhibits a significant structural change upon photoactivation. A rarely considered aspect is the importance of internal protein dynamics in facilitating the structural transition to the active state. In this study, we use quasielastic neutron scattering under (in situ) blue light illumination for the first time to directly probe the protein dynamics of the orange carotenoid protein in the dark-adapted and active states. This shows that the localized internal dynamics of amino acid residues is significantly enhanced upon photoactivation. This is attributed to the photoinduced structural changes exposing larger areas of the protein surface to the solvent, thus resulting in a higher degree of motional freedom. However, the flexibility of the W288A mutant assumed to mimic the active state structure is found to be different, thus highlighting the importance of in situ experiments.
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Affiliation(s)
- Maksym Golub
- Institute of Physics, University of Tartu, W. Ostwald strasse 1, 50411 Tartu, Estonia
| | - Marcus Moldenhauer
- Technische Universität Berlin, Institute of Chemistry PC 14, Straße des 17, Juni 135, 10623 Berlin, Germany
| | - Franz-Josef Schmitt
- Martin-Luther-Universität Halle Wittenberg, Institute of Physics, Von-Danckelmann-Platz 3, 06120 Halle, Germany
| | - Wiebke Lohstroh
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstraße 1, 85748 Garching, Germany
| | - Thomas Friedrich
- Technische Universität Berlin, Institute of Chemistry PC 14, Straße des 17, Juni 135, 10623 Berlin, Germany
| | - Jörg Pieper
- Institute of Physics, University of Tartu, W. Ostwald strasse 1, 50411 Tartu, Estonia
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6
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Lenton S, Fagerberg E, Tully M, Skepö M. From dilute to concentrated solutions of intrinsically disordered proteins: Interpretation and analysis of collected data. Methods Enzymol 2022; 678:299-330. [PMID: 36641212 DOI: 10.1016/bs.mie.2022.09.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Intrinsically disordered proteins (IDPs) have a broad energy landscape and consequently sample many different conformations in solution. The innate flexibility of IDPs is exploited in their biological function, and in many instances allows a single IDP to regulate a range of processes in vivo. Due to their highly flexible nature, characterizing the structural properties of IDPs is not straightforward. Often solution-based methods such as Nuclear Magnetic Resonance (NMR), Förster Resonance Energy Transfer (FRET), and Small-Angle X-ray Scattering (SAXS) are used. SAXS is indeed a powerful technique to study the structural and conformational properties of IDPs in solution, and from the obtained SAXS spectra, information about the average size, shape, and extent of oligomerization can be determined. In this chapter, we will introduce model-free methods that can be used to interpret SAXS data and introduce methods that can be used to interpret SAXS data beyond analytical models, for example, by using atomistic and different levels of coarse-grained models in combination with molecular dynamics (MD) and Monte Carlo simulations.
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Affiliation(s)
- Samuel Lenton
- Drug Delivery and Biophysics of Biopharmaceuticals, Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark; Division of Theoretical Chemistry, Lund University, Lund, Sweden
| | - Eric Fagerberg
- Division of Theoretical Chemistry, Lund University, Lund, Sweden
| | - Mark Tully
- BioSAXS beamline, BM29, European Synchrotron Radiation Facility, ESRF, Grenoble, France
| | - Marie Skepö
- Division of Theoretical Chemistry, Lund University, Lund, Sweden; LINXS-Institute of Advanced Neutron and X-ray Science, Lund, Sweden.
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7
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Beck C, Grimaldo M, Lopez H, Da Vela S, Sohmen B, Zhang F, Oettel M, Barrat JL, Roosen-Runge F, Schreiber F, Seydel T. Short-Time Transport Properties of Bidisperse Suspensions of Immunoglobulins and Serum Albumins Consistent with a Colloid Physics Picture. J Phys Chem B 2022; 126:7400-7408. [PMID: 36112146 PMCID: PMC9527755 DOI: 10.1021/acs.jpcb.2c02380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The crowded environment of biological systems such as
the interior
of living cells is occupied by macromolecules with a broad size distribution.
This situation of polydispersity might influence the dependence of
the diffusive dynamics of a given tracer macromolecule in a monodisperse
solution on its hydrodynamic size and on the volume fraction. The
resulting size dependence of diffusive transport crucially influences
the function of a living cell. Here, we investigate a simplified model
system consisting of two constituents in aqueous solution, namely,
of the proteins bovine serum albumin (BSA) and bovine polyclonal gamma-globulin
(Ig), systematically depending on the total volume fraction and ratio
of these constituents. From high-resolution quasi-elastic neutron
spectroscopy, the separate apparent short-time diffusion coefficients
for BSA and Ig in the mixture are extracted, which show substantial
deviations from the diffusion coefficients measured in monodisperse
solutions at the same total volume fraction. These deviations can
be modeled quantitatively using results from the short-time rotational
and translational diffusion in a two-component hard sphere system
with two distinct, effective hydrodynamic radii. Thus, we find that
a simple colloid picture well describes short-time diffusion in binary
mixtures as a function of the mixing ratio and the total volume fraction.
Notably, the self-diffusion of the smaller protein BSA in the mixture
is faster than the diffusion in a pure BSA solution, whereas the self-diffusion
of Ig in the mixture is slower than in the pure Ig solution.
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Affiliation(s)
- Christian Beck
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
- Institut Max von Laue─Paul Langevin (ILL), CS 20156, F-38042 Grenoble Cedex 9, France
| | - Marco Grimaldo
- Institut Max von Laue─Paul Langevin (ILL), CS 20156, F-38042 Grenoble Cedex 9, France
| | - Hender Lopez
- School of Physics and Optometric & Clinical Sciences, Technological University Dublin, D07 XT95 Grangegorman, Ireland
| | - Stefano Da Vela
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Benedikt Sohmen
- Institut für Angewandte Physik, Universität Tübingen, 72076 Tübingen, Germany
| | - Fajun Zhang
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Martin Oettel
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | | | - Felix Roosen-Runge
- Department of Biomedical Science and Biofilms-Research Center for Biointerfaces (BRCB), Malmö University, 20506 Malmö, Sweden
| | - Frank Schreiber
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Tilo Seydel
- Institut Max von Laue─Paul Langevin (ILL), CS 20156, F-38042 Grenoble Cedex 9, France
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8
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Raskar T, Niebling S, Devos JM, Yorke BA, Härtlein M, Huse N, Forsyth VT, Seydel T, Pearson AR. Structure and diffusive dynamics of aspartate α-decarboxylase (ADC) liganded with D-serine in aqueous solution. Phys Chem Chem Phys 2022; 24:20336-20347. [PMID: 35980136 PMCID: PMC9429672 DOI: 10.1039/d2cp02063g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Incoherent neutron spectroscopy, in combination with dynamic light scattering, was used to investigate the effect of ligand binding on the center-of-mass self-diffusion and internal diffusive dynamics of Escherichia coli aspartate α-decarboxylase (ADC). The X-ray crystal structure of ADC in complex with the d-serine inhibitor was also determined, and molecular dynamics simulations were used to further probe the structural rearrangements that occur as a result of ligand binding. These experiments reveal that d-serine forms hydrogen bonds with some of the active site residues, that higher order oligomers of the ADC tetramer exist on ns–ms time-scales, and also show that ligand binding both affects the ADC internal diffusive dynamics and appears to further increase the size of the higher order oligomers. Neutron spectroscopy, dynamic light scattering, X-ray diffraction, and MD-simulations were used to investigate the effect of ligand binding on the structure and diffusive dynamics of Escherichia coli aspartate alpha-decarboxylase.![]()
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Affiliation(s)
- Tushar Raskar
- Institut Max von Laue - Paul Langevin, 71 Avenue des Martyrs, Grenoble 38000, France. .,Partnership for Structural Biology, 71 Avenue des Martyrs, Grenoble 38000, France.,Institute for Nanostructure and Solid State Physics, Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, Hamburg, 22761, Germany.
| | - Stephan Niebling
- Institute for Nanostructure and Solid State Physics, Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, Hamburg, 22761, Germany. .,European Molecular Biology Laboratory, Hamburg, Notkestr. 85, 22607 Hamburg, Germany
| | - Juliette M Devos
- Institut Max von Laue - Paul Langevin, 71 Avenue des Martyrs, Grenoble 38000, France. .,Partnership for Structural Biology, 71 Avenue des Martyrs, Grenoble 38000, France
| | - Briony A Yorke
- School of Chemistry and Bioscience, University of Bradford, Bradford, BD7 1DP, UK
| | - Michael Härtlein
- Institut Max von Laue - Paul Langevin, 71 Avenue des Martyrs, Grenoble 38000, France. .,Partnership for Structural Biology, 71 Avenue des Martyrs, Grenoble 38000, France
| | - Nils Huse
- Institute for Nanostructure and Solid State Physics, Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, Hamburg, 22761, Germany.
| | - V Trevor Forsyth
- Institut Max von Laue - Paul Langevin, 71 Avenue des Martyrs, Grenoble 38000, France. .,Partnership for Structural Biology, 71 Avenue des Martyrs, Grenoble 38000, France.,Faculty of Natural Sciences, Keele University, Staffordshire, ST5 5BG, UK
| | - Tilo Seydel
- Institut Max von Laue - Paul Langevin, 71 Avenue des Martyrs, Grenoble 38000, France.
| | - Arwen R Pearson
- Institute for Nanostructure and Solid State Physics, Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, Hamburg, 22761, Germany.
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9
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Unravelling the Adaptation Mechanisms to High Pressure in Proteins. Int J Mol Sci 2022; 23:ijms23158469. [PMID: 35955607 PMCID: PMC9369236 DOI: 10.3390/ijms23158469] [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: 07/06/2022] [Revised: 07/26/2022] [Accepted: 07/27/2022] [Indexed: 02/06/2023] Open
Abstract
Life is thought to have appeared in the depth of the sea under high hydrostatic pressure. Nowadays, it is known that the deep biosphere hosts a myriad of life forms thriving under high-pressure conditions. However, the evolutionary mechanisms leading to their adaptation are still not known. Here, we show the molecular bases of these mechanisms through a joint structural and dynamical study of two orthologous proteins. We observed that pressure adaptation involves the decoupling of protein–water dynamics and the elimination of cavities in the protein core. This is achieved by rearranging the charged residues on the protein surface and using bulkier hydrophobic residues in the core. These findings will be the starting point in the search for a complete genomic model explaining high-pressure adaptation.
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10
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Panjwani D, Patel S, Mishra D, Patel V, Yadav M, Dharamsi A, Patel A. Avidin-Biotin functionalized self-assembled protein nanoparticles as EGFR targeted therapeutics for the treatment of lung cancer: characterization and cell viability. J DISPER SCI TECHNOL 2022. [DOI: 10.1080/01932691.2022.2099888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Drishti Panjwani
- Department of Pharmaceutics, Parul Institute of Pharmacy, Parul University, Vadodara, Gujarat, India
| | - Shruti Patel
- Department of Pharmaceutics, Parul Institute of Pharmacy, Parul University, Vadodara, Gujarat, India
| | - Deepak Mishra
- Department of Pharmaceutics, Parul Institute of Pharmacy, Parul University, Vadodara, Gujarat, India
| | - Viral Patel
- Department of Civil and Petroleum Engineering, University of Alberta, Edmonton, Alberta, Canada
| | - MangeRam Yadav
- Centre for Research and Development, Parul Institute of Pharmacy, Parul University, Vadodara, Gujarat, India
| | - Abhay Dharamsi
- Parul Institute of Pharmacy, Parul University, Vadodara, Gujarat, India
| | - Asha Patel
- Department of Pharmaceutics, Parul Institute of Pharmacy, Parul University, Vadodara, Gujarat, India
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11
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Rastogi H, Chowdhury PK. Correlating the Local and Global Dynamics of an Enzyme in the Crowded Milieu. J Phys Chem B 2022; 126:3208-3223. [PMID: 35442681 DOI: 10.1021/acs.jpcb.1c09759] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Enzymes are dynamic biological macromolecules, with their catalytic function(s) being largely influenced by the changes in local fluctuations of amino acid side chains as well as global structural modulations that the enzyme undergoes. Such local and global motions can be highly affected inside the crowded physiological interior of the cell. Here, we have addressed the role of dynamic structural flexibility in affecting the activation energy barrier of a flexible multidomain enzyme adenylate kinase (AK3L1, UniProtKB: Q9UIJ7). Activation energy profiles of both local (at three different sites along the polypeptide backbone) and global dynamics of the enzyme have been monitored using solvation studies on the subnanosecond time scale and tryptophan quenching studies over the temperature range of 278-323 K, respectively, under crowded conditions (Ficoll 70, Dextran 40, Dextran 70, and PEG 8). This study not only provides the site-specific mapping of dynamics but reveals that the activation energies associated with these local motions undergo a significant decrease in the presence of macromolecular crowders, providing new insights into how crowding affects internal protein dynamics. The crowded scenario also aids in enhancing the coupling between the local and global motions of the enzyme. Moreover, select portions/regions of the enzyme when taken together can well mirror the overall dynamics of the biomolecule, showing possible energy hotspots along the polypeptide backbone.
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Affiliation(s)
- Harshita Rastogi
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India 110016
| | - Pramit K Chowdhury
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India 110016
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12
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Beck C, Pounot K, Mosca I, H Jalarvo N, Roosen-Runge F, Schreiber F, Seydel T. Notes on Fitting and Analysis Frameworks for QENS Spectra of (Soft) Colloid Suspensions. EPJ WEB OF CONFERENCES 2022. [DOI: 10.1051/epjconf/202227201004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
With continuously improving signal-to-noise ratios, a statistically sound analysis of quasi-elastic neutron scattering (QENS) spectra requires to fit increasingly complex models which poses several challenges. Simultaneous fits of the spectra for all recorded values of the momentum transfer become a standard approach. Spectrometers at spallation sources can have a complicated non-Gaussian resolution function which has to be described most accurately. At the same time, to speed up the fitting, an analytical convolution with this resolution function is of interest. Here, we discuss basic concepts to efficient approaches for fits of QENS spectra based on standard MATLAB and Python fit algorithms. We illustrate the fits with example data from IN16B, BASIS, and BATS.
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13
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Nakagawa H, Appavou MS, Wuttke J, Zamponi M, Holderer O, Schrader TE, Richter D, Doster W. Nanosecond structural dynamics of intrinsically disordered β-casein micelles by neutron spectroscopy. Biophys J 2021; 120:5408-5420. [PMID: 34717964 PMCID: PMC8715185 DOI: 10.1016/j.bpj.2021.10.032] [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: 10/13/2020] [Revised: 09/17/2021] [Accepted: 10/13/2021] [Indexed: 10/20/2022] Open
Abstract
β-casein undergoes a reversible endothermic self-association, forming protein micelles of limited size. In its functional state, a single β-casein monomer is unfolded, which creates a high structural flexibility, which is supposed to play a major role in preventing the precipitation of calcium phosphate particles. We characterize the structural flexibility in terms of nanosecond molecular motions, depending on the temperature by quasielastic neutron scattering. Our major questions are: Does the self-association reduce the chain flexibility? How does the dynamic spectrum of disordered caseins differ from a compactly globular protein? How does the dynamic spectrum of β-casein in solution differ from that of a protein in hydrated powder states? We report on two relaxation processes on a nanosecond and a sub-nanosecond timescale for β-casein in solution. Both processes are analyzed by Brownian oscillator model, by which the spring constant can be defined in the isotropic parabolic potential. The slower process, which is analyzed by neutron spin echo, seems a characteristic feature of the unfolded structure. It requires bulk solvent and is not seen in hydrated protein powders. The faster process, which is analyzed by neutron backscattering, has a smaller amplitude and requires hydration water, which is also observed with folded proteins in the hydrated state. The self-association had no significant influence on internal relaxation, and thus, a β-casein protein monomer flexibility is preserved in the micelle. We derive spring constants of the faster and slower motions of β-caseins in solution and compared them with those of some proteins in various states (folded or hydrated powder).
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Affiliation(s)
- Hiroshi Nakagawa
- Materials Sciences Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan; Forschungszentrum Jülich, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Garching, Germany; J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan.
| | - Marie-Sousai Appavou
- Forschungszentrum Jülich, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Garching, Germany
| | - Joachim Wuttke
- Forschungszentrum Jülich, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Garching, Germany
| | - Michaela Zamponi
- Forschungszentrum Jülich, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Garching, Germany
| | - Olaf Holderer
- Forschungszentrum Jülich, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Garching, Germany
| | - Tobias E Schrader
- Forschungszentrum Jülich, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Garching, Germany
| | - Dieter Richter
- Forschungszentrum Jülich, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum, Garching, Germany
| | - Wolfgang Doster
- Technische Universität München, Physik-Department, Garching, Germany
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14
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Beck C, Grimaldo M, Braun MK, Bühl L, Matsarskaia O, Jalarvo NH, Zhang F, Roosen-Runge F, Schreiber F, Seydel T. Temperature and salt controlled tuning of protein clusters. SOFT MATTER 2021; 17:8506-8516. [PMID: 34490428 DOI: 10.1039/d1sm00418b] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The formation of molecular assemblies in protein solutions is of strong interest both from a fundamental viewpoint and for biomedical applications. While ordered and desired protein assemblies are indispensable for some biological functions, undesired protein condensation can induce serious diseases. As a common cofactor, the presence of salt ions is essential for some biological processes involving proteins, and in aqueous suspensions of proteins can also give rise to complex phase diagrams including homogeneous solutions, large aggregates, and dissolution regimes. Here, we systematically study the cluster formation approaching the phase separation in aqueous solutions of the globular protein BSA as a function of temperature (T), the protein concentration (cp) and the concentrations of the trivalent salts YCl3 and LaCl3 (cs). As an important complement to structural, i.e. time-averaged, techniques we employ a dynamical technique that can detect clusters even when they are transient on the order of a few nanoseconds. By employing incoherent neutron spectroscopy, we unambiguously determine the short-time self-diffusion of the protein clusters depending on cp, cs and T. We determine the cluster size in terms of effective hydrodynamic radii as manifested by the cluster center-of-mass diffusion coefficients D. For both salts, we find a simple functional form D(cp, cs, T) in the parameter range explored. The calculated inter-particle attraction strength, determined from the microscopic and short-time diffusive properties of the samples, increases with salt concentration and temperature in the regime investigated and can be linked to the macroscopic behavior of the samples.
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Affiliation(s)
- Christian Beck
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France.
| | - Marco Grimaldo
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France.
| | - Michal K Braun
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Lena Bühl
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Olga Matsarskaia
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France.
| | - Niina H Jalarvo
- Jülich Centre for Neutron Science (JCNS), Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Chemical and Engineering Materials Division, Neutron Sciences Directorate, and JCNS Outstation at the Spallation Neutron Source (SNS), Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, USA
| | - Fajun Zhang
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Felix Roosen-Runge
- Department of Biomedical Sciences and Biofilms-Research Center for Biointerfaces (BRCB), Malmö University, 20506 Malmö, Sweden.
- Division of Physical Chemistry, Lund University, Naturvetarvägen 14, 22100 Lund, Sweden
| | - Frank Schreiber
- Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Tilo Seydel
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble, France.
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15
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Katava M, Stirnemann G, Pachetti M, Capaccioli S, Paciaroni A, Sterpone F. Specific Interactions and Environment Flexibility Tune Protein Stability under Extreme Crowding. J Phys Chem B 2021; 125:6103-6111. [PMID: 34100611 DOI: 10.1021/acs.jpcb.1c01511] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Macromolecular crowding influences protein mobility and stability in vivo. A precise description of the crowding effect on protein thermal stability requires the estimate of the combined effects of excluded volume, specific protein-environment interactions, as well as the thermal response of the crowders. Here, we explore an ideal model system, the lysozyme protein in powder state, to dissect the factors controlling the melting of the protein under extreme crowding. By deploying state-of-the art molecular simulations, supported by calorimetric experiments, we assess the role of the environment flexibility and of intermolecular electrostatic interactions. In particular, we show that the temperature-dependent flexibility of the macromolecular crowders, along with specific interactions, significantly alleviates the stabilizing contributions of the static volume effect.
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Affiliation(s)
- Marina Katava
- Laboratoire de Biochimie Théorique, IBPC, CNRS UPR9080, Université Paris Diderot, Sorbonne Paris Cité, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Guillaume Stirnemann
- Laboratoire de Biochimie Théorique, IBPC, CNRS UPR9080, Université Paris Diderot, Sorbonne Paris Cité, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Maria Pachetti
- Elettra-Sincrotrone Trieste, S.S. 14 km 163.5, Area Science Park, 34149 Trieste, Italy.,Department of Physics, University of Trieste, Via Valerio 2, 34127 Trieste, Italy
| | - Simone Capaccioli
- Dipartimento di Fisica, Universitá di Pisa, largo Pontecorvo 3, 56127 Pisa, Italy.,CISUP, Centro per l'Integrazione della Strumentazione dell'Università di Pisa, Lungarno Pacinotti 43, I-56127 Pisa, Italy
| | - Alessandro Paciaroni
- Dipartimento di Fisica e Geologia, Universitá di Perugia, via A. Pascoli, 06123 Perugia, Italy
| | - Fabio Sterpone
- Laboratoire de Biochimie Théorique, IBPC, CNRS UPR9080, Université Paris Diderot, Sorbonne Paris Cité, 13 rue Pierre et Marie Curie, 75005 Paris, France
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16
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Matsarskaia O, Bühl L, Beck C, Grimaldo M, Schweins R, Zhang F, Seydel T, Schreiber F, Roosen-Runge F. Evolution of the structure and dynamics of bovine serum albumin induced by thermal denaturation. Phys Chem Chem Phys 2020; 22:18507-18517. [PMID: 32780038 DOI: 10.1039/d0cp01857k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Protein denaturation in concentrated solutions consists of the unfolding of the native protein structure, and subsequent cross-linking into clusters or gel networks. While the kinetic evolution of structure has been studied for some cases, the underlying microscopic dynamics of proteins has so far been neglected. However, protein dynamics is essential to understand the specific nature of assembly processes, such as diffusion-limited growth, or vitrification of dense liquids. Here, we present a study on thermal denaturation of concentrated solutions of bovine serum albumin (BSA) in D2O with and without NaCl. Using small-angle scattering, we provide information on structure before, during and after denaturation. Using quasi-elastic neutron scattering, we monitor in real-time the microscopic dynamics and dynamical confinement throughout the entire denaturation process covering protein unfolding and cross-linking. After denaturation, the protein dynamics is slowed down in salty solutions compared to those in pure water, while the stability and dynamics of the native solution appears unaffected by salt. The approach presented here opens opportunities to link microscopic dynamics to emerging structural properties, with implications for assembly processes in soft and biological matter.
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Affiliation(s)
- Olga Matsarskaia
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, France.
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17
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Matsarskaia O, Roosen‐Runge F, Schreiber F. Multivalent ions and biomolecules: Attempting a comprehensive perspective. Chemphyschem 2020; 21:1742-1767. [PMID: 32406605 PMCID: PMC7496725 DOI: 10.1002/cphc.202000162] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 05/13/2020] [Indexed: 12/13/2022]
Abstract
Ions are ubiquitous in nature. They play a key role for many biological processes on the molecular scale, from molecular interactions, to mechanical properties, to folding, to self-organisation and assembly, to reaction equilibria, to signalling, to energy and material transport, to recognition etc. Going beyond monovalent ions to multivalent ions, the effects of the ions are frequently not only stronger (due to the obviously higher charge), but qualitatively different. A typical example is the process of binding of multivalent ions, such as Ca2+ , to a macromolecule and the consequences of this ion binding such as compaction, collapse, potential charge inversion and precipitation of the macromolecule. Here we review these effects and phenomena induced by multivalent ions for biological (macro)molecules, from the "atomistic/molecular" local picture of (potentially specific) interactions to the more global picture of phase behaviour including, e. g., crystallisation, phase separation, oligomerisation etc. Rather than attempting an encyclopedic list of systems, we rather aim for an embracing discussion using typical case studies. We try to cover predominantly three main classes: proteins, nucleic acids, and amphiphilic molecules including interface effects. We do not cover in detail, but make some comparisons to, ion channels, colloidal systems, and synthetic polymers. While there are obvious differences in the behaviour of, and the relevance of multivalent ions for, the three main classes of systems, we also point out analogies. Our attempt of a comprehensive discussion is guided by the idea that there are not only important differences and specific phenomena with regard to the effects of multivalent ions on the main systems, but also important similarities. We hope to bridge physico-chemical mechanisms, concepts of soft matter, and biological observations and connect the different communities further.
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Affiliation(s)
| | - Felix Roosen‐Runge
- Department of Biomedical Sciences and Biofilms-Research Center for Biointerfaces (BRCB), Faculty of Health and SocietyMalmö UniversitySweden
- Division of Physical ChemistryLund UniversitySweden
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18
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Shiraga K, Urabe M, Matsui T, Kikuchi S, Ogawa Y. Highly precise characterization of the hydration state upon thermal denaturation of human serum albumin using a 65 GHz dielectric sensor. Phys Chem Chem Phys 2020; 22:19468-19479. [PMID: 32761010 DOI: 10.1039/d0cp02265a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The biological functions of proteins depend on harmonization with hydration water surrounding them. Indeed, the dynamical transition of proteins, such as thermal denaturation, is dependent on the changes in the mobility of hydration water. However, the role of hydration water during dynamical transition is yet to be fully understood due to technical limitations in precisely characterizing the amount of hydration water. A state-of-the-art CMOS dielectric sensor consisting of 65 GHz LC resonators addressed this issue by utilizing the feature that oscillation frequency sensitively shifts in response to the complex dielectric constant at 65 GHz with extremely high precision. This study aimed to establish an analytical algorithm to derive the hydration number from the measured frequency shift and to demonstrate the transition of hydration number upon the thermal denaturation of human serum albumin. The determined hydration number in the native state drew a "global" hydration picture beyond the first solvation shell, with substantially reduced uncertainty of the hydration number (about ±1%). This allowed the detection of a rapid increase in the hydration number at about 55 °C during the heating process, which was in excellent phase with the irreversible rupture of the α-helical structure into solvent-exposed extended chains, whereas the hydration number did not trace the forward path in the subsequent cooling process. Our result indicates that the weakening of water hydrogen bonds trigger the unfolding of the protein structure first, followed by the changes in the number of hydration water as a consequence of thermal denaturation.
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Affiliation(s)
- Keiichiro Shiraga
- RIKEN Center for Integrative Medical Sciences (IMS), Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
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19
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Pounot K, Chaaban H, Foderà V, Schirò G, Weik M, Seydel T. Tracking Internal and Global Diffusive Dynamics During Protein Aggregation by High-Resolution Neutron Spectroscopy. J Phys Chem Lett 2020; 11:6299-6304. [PMID: 32663030 DOI: 10.1021/acs.jpclett.0c01530] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Proteins can misfold and form either amorphous or organized aggregates with different morphologies and features. Aggregates of amyloid nature are pathological hallmarks in so-called protein conformational diseases, including Alzheimer's and Parkinson's. Evidence prevails that the transient early phases of the reaction determine the aggregate morphology and toxicity. As a consequence, real-time monitoring of protein aggregation is of utmost importance. Here, we employed time-resolved neutron backscattering spectroscopy to follow center-of-mass self-diffusion and nano- to picosecond internal dynamics of lysozyme during aggregation into a specific β-sheet rich superstructure, called particulates, formed at the isoelectric point of the protein. Particulate formation is found to be a one-step process, and protein internal dynamics, to remain unchanged during the entire aggregation process. The time-resolved neutron backscattering spectroscopy approach developed here, in combination with standard kinetics assays, provides a unifying framework in which dynamics and conformational transitions can be related to the different aggregation pathways.
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Affiliation(s)
- Kevin Pounot
- Université Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, F-38000 Grenoble, France
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, CS 20156, F-38042 Grenoble cedex 9, France
| | - Hussein Chaaban
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Vito Foderà
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Giorgio Schirò
- Université Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, F-38000 Grenoble, France
| | - Martin Weik
- Université Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, F-38000 Grenoble, France
| | - Tilo Seydel
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, CS 20156, F-38042 Grenoble cedex 9, France
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20
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Seydel T, Koza MM, Matsarskaia O, André A, Maiti S, Weber M, Schweins R, Prévost S, Schreiber F, Scheele M. A neutron scattering perspective on the structure, softness and dynamics of the ligand shell of PbS nanocrystals in solution. Chem Sci 2020; 11:8875-8884. [PMID: 34123141 PMCID: PMC8163380 DOI: 10.1039/d0sc02636k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 08/01/2020] [Indexed: 12/02/2022] Open
Abstract
Small-angle neutron and X-ray scattering, neutron backscattering and neutron time-of-flight spectroscopy are applied to reveal the structure of the ligand shell, the temperature-dependent diffusion properties and the phonon spectrum of PbS nanocrystals functionalized with oleic acid in deuterated hexane. The nanocrystals decorated with oleic acid as well as the desorbed ligand molecules exhibit simple Brownian diffusion with a Stokes-Einstein temperature-dependence and inhibited freezing. Ligand molecules desorbed from the surface show strong spatial confinement. The phonon spectrum of oleic acid adsorbed to the nanocrystal surface exhibits hybrid modes with a predominant Pb-character. Low-energy surface modes of the NCs are prominent and indicate a large mechanical softness in solution. This work provides comprehensive insights into the ligand-particle interaction of colloidal nanocrystals in solution and highlights its effect on the diffusion and vibrational properties as well as their mechanical softness.
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Affiliation(s)
- Tilo Seydel
- Institut Max von Laue - Paul Langevin (ILL) 71 Avenue des Martyrs, CS 20156 38042 Grenoble Cedex 9 France
| | - Michael Marek Koza
- Institut Max von Laue - Paul Langevin (ILL) 71 Avenue des Martyrs, CS 20156 38042 Grenoble Cedex 9 France
| | - Olga Matsarskaia
- Institut Max von Laue - Paul Langevin (ILL) 71 Avenue des Martyrs, CS 20156 38042 Grenoble Cedex 9 France
| | - Alexander André
- Institute of Physical and Theoretical Chemistry, University of Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Santanu Maiti
- Institute of Applied Physics, University of Tübingen Auf der Morgenstelle 10 72076 Tübingen Germany
| | - Michelle Weber
- Institute of Physical and Theoretical Chemistry, University of Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Ralf Schweins
- Institut Max von Laue - Paul Langevin (ILL) 71 Avenue des Martyrs, CS 20156 38042 Grenoble Cedex 9 France
| | - Sylvain Prévost
- ESRF - The European Synchrotron 71 Avenue des Martyrs, CS 40220 38043 Grenoble Cedex 9 France
| | - Frank Schreiber
- Institute of Applied Physics, University of Tübingen Auf der Morgenstelle 10 72076 Tübingen Germany
- Center for Light-Matter Interaction, Sensors & Analytics LISA+, University of Tübingen Auf der Morgenstelle 15 72076 Tübingen Germany
| | - Marcus Scheele
- Institute of Physical and Theoretical Chemistry, University of Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
- Center for Light-Matter Interaction, Sensors & Analytics LISA+, University of Tübingen Auf der Morgenstelle 15 72076 Tübingen Germany
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21
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Salvador-Castell M, Golub M, Martinez N, Ollivier J, Peters J, Oger P. The first study on the impact of osmolytes in whole cells of high temperature-adapted microorganisms. SOFT MATTER 2019; 15:8381-8391. [PMID: 31613294 DOI: 10.1039/c9sm01196j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The hyperthermophilic piezophile, Thermococcus barophilus displays a strong stress response characterized by the accumulation of the organic osmolyte, mannosylglycerate during growth under sub-optimal pressure conditions (0.1 MPa). Taking advantage of this known effect, the impact of osmolytes in piezophiles in an otherwise identical cellular context was investigated, by comparing T. barophilus cells grown under low or optimal pressures (40 MPa). Using neutron scattering techniques, we studied the molecular dynamics of live cells of T. barophilus at different pressures and temperatures. We show that in the presence of osmolytes, cells present a higher diffusion coefficient of hydration water and an increase of bulk water motions at a high temperature. In the absence of osmolytes, the T. barophilus cellular dynamics is more responsive to high temperature and high hydrostatic pressure. These results therefore give clear evidence for a protecting effect of osmolytes on proteins.
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22
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Ameseder F, Biehl R, Holderer O, Richter D, Stadler AM. Localised contacts lead to nanosecond hinge motions in dimeric bovine serum albumin. Phys Chem Chem Phys 2019; 21:18477-18485. [PMID: 31210243 DOI: 10.1039/c9cp01847f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Domain motions in proteins are crucial for biological function. In the present manuscript, we present a neutron spin-echo spectroscopy (NSE) study of native bovine serum albumin (BSA) in solution. NSE allows to probe both global and internal dynamics of the BSA monomer and dimer equilibrium that is formed in solution. Using a model independent approach, we were able to identify an internal dynamic process in BSA that is visible in addition to global rigid-body diffusion of the BSA monomer and dimer mixture. The observed internal protein motion is characterised by a relaxation time of 43 ns. The overdamped Brownian oscillator was considered as an alternative analytical theory that was able to describe the internal process as first-order approximation. More detailed information on the physical nature of the internal protein motion was extracted from the q-dependent internal diffusion coefficients ΔDeff(q) that were detected by NSE in addition to global rigid-body translational and rotational diffusion. The ΔDeff(q) were interpreted using normal mode analysis based on the available crystal structures of the BSA monomer and dimer as structural test models. Normal mode analysis demonstrates that the observed internal dynamic process can be attributed to bending motion of the BSA dimer. The native BSA monomer does not show any internal dynamics on the time- and length-scales probed by NSE. An intermolecular disulphide bridge or a direct structural contact between the BSA monomers forms a localised link acting as a molecular hinge in the BSA dimer. The effect of that hinge on the observed motion of BSA in the used dimeric structural model is discussed in terms of normal modes in a molecular picture.
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Affiliation(s)
- Felix Ameseder
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
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23
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Abstract
AbstractThe dynamics of proteins in solution includes a variety of processes, such as backbone and side-chain fluctuations, interdomain motions, as well as global rotational and translational (i.e. center of mass) diffusion. Since protein dynamics is related to protein function and essential transport processes, a detailed mechanistic understanding and monitoring of protein dynamics in solution is highly desirable. The hierarchical character of protein dynamics requires experimental tools addressing a broad range of time- and length scales. We discuss how different techniques contribute to a comprehensive picture of protein dynamics, and focus in particular on results from neutron spectroscopy. We outline the underlying principles and review available instrumentation as well as related analysis frameworks.
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24
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Beck C, Grimaldo M, Roosen-Runge F, Braun MK, Zhang F, Schreiber F, Seydel T. Nanosecond Tracer Diffusion as a Probe of the Solution Structure and Molecular Mobility of Protein Assemblies: The Case of Ovalbumin. J Phys Chem B 2018; 122:8343-8350. [PMID: 30106587 DOI: 10.1021/acs.jpcb.8b04349] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Protein diffusion is not only an important process ensuring biological function but can also be used as a probe to obtain information on structural properties of protein assemblies in liquid solutions. Here, we explore the oligomerization state of ovalbumin at high protein concentrations by means of its short-time self-diffusion. We employ high-resolution incoherent quasielastic neutron scattering to access the self-diffusion on nanosecond timescales, on which interparticle contacts are not altered. Our results indicate that ovalbumin in aqueous (D2O) solutions occurs in increasingly large assemblies of its monomeric subunits with rising protein concentration. It changes from nearly monomeric toward dimeric and ultimately larger than tetrameric complexes. Simultaneously, we access information on the internal molecular mobility of ovalbumin on the nanometer length scale and compare it with results obtained for bovine serum albumin, immunoglobulin, and β-lactoglobulin.
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Affiliation(s)
- Christian Beck
- Institut Max von Laue-Paul Langevin (ILL) , B.P.156, F-38042 Grenoble , France.,Institut für Angewandte Physik , Universität Tübingen , Auf der Morgenstelle 10 , 72076 Tübingen , Germany
| | - Marco Grimaldo
- Institut Max von Laue-Paul Langevin (ILL) , B.P.156, F-38042 Grenoble , France
| | - Felix Roosen-Runge
- Division of Physical Chemistry, Department of Chemistry , Lund University , Naturvetarvägen 16 , SE-22100 Lund , Sweden
| | - Michal K Braun
- Institut für Angewandte Physik , Universität Tübingen , Auf der Morgenstelle 10 , 72076 Tübingen , Germany
| | - Fajun Zhang
- Institut für Angewandte Physik , Universität Tübingen , Auf der Morgenstelle 10 , 72076 Tübingen , Germany
| | - Frank Schreiber
- Institut für Angewandte Physik , Universität Tübingen , Auf der Morgenstelle 10 , 72076 Tübingen , Germany
| | - Tilo Seydel
- Institut Max von Laue-Paul Langevin (ILL) , B.P.156, F-38042 Grenoble , France
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25
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Abstract
Living planarian flatworms were probed using quasielastic neutron scattering to measure, on the pico-to-nanosecond time scale and nanometer length scale, microscopic diffusion of water and cell constituents in the planarians. Measurable microscopic diffusivities were surprisingly well defined in such a complex system as living animals. The overall variation in the microscopic diffusivity of cell constituents was found to be far lower than the variation in the microscopic diffusivity of water in planarians in a temperature range of 284.5 to 304.1 K.
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26
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Ameseder F, Radulescu A, Khaneft M, Lohstroh W, Stadler AM. Homogeneous and heterogeneous dynamics in native and denatured bovine serum albumin. Phys Chem Chem Phys 2018; 20:5128-5139. [DOI: 10.1039/c7cp08292d] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Quasielastic incoherent neutron spectroscopy experiments reveal that chemical denaturation significantly modifies the internal dynamics of bovine serum albumin.
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Affiliation(s)
- Felix Ameseder
- Jülich Centre for Neutron Science JCNS and Institute for Complex Systems ICS
- Forschungszentrum Jülich GmbH
- 52425 Jülich
- Germany
| | - Aurel Radulescu
- Jülich Centre for Neutron Science JCNS
- Forschungszentrum Jülich GmbH, Outstation at MLZ
- 85747 Garching
- Germany
| | - Marina Khaneft
- Jülich Centre for Neutron Science JCNS
- Forschungszentrum Jülich GmbH, Outstation at MLZ
- 85747 Garching
- Germany
| | - Wiebke Lohstroh
- Heinz Maier-Leibnitz Zentrum
- Technische Universität München
- 85747 Garching
- Germany
| | - Andreas M. Stadler
- Jülich Centre for Neutron Science JCNS and Institute for Complex Systems ICS
- Forschungszentrum Jülich GmbH
- 52425 Jülich
- Germany
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27
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Honegger P, Schmollngruber M, Steinhauser O. Macromolecular crowding and the importance of proper hydration for the structure and dynamics of protein solutions. Phys Chem Chem Phys 2018; 20:19581-19594. [DOI: 10.1039/c8cp02360c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Extensive computational studies of ubiquitin crowding with a special focus on protein hydration directly visible in dielectric spectra.
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Affiliation(s)
- Philipp Honegger
- University of Vienna
- Faculty of Chemistry
- Department of Computational Biological Chemistry
- A-1090 Vienna
- Austria
| | - Michael Schmollngruber
- University of Vienna
- Faculty of Chemistry
- Department of Computational Biological Chemistry
- A-1090 Vienna
- Austria
| | - Othmar Steinhauser
- University of Vienna
- Faculty of Chemistry
- Department of Computational Biological Chemistry
- A-1090 Vienna
- Austria
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28
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Noorani M, Azarpira N, Karimian K, Heli H. Erlotinib-loaded albumin nanoparticles: A novel injectable form of erlotinib and its in vivo efficacy against pancreatic adenocarcinoma ASPC-1 and PANC-1 cell lines. Int J Pharm 2017; 531:299-305. [DOI: 10.1016/j.ijpharm.2017.08.102] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/17/2017] [Accepted: 08/21/2017] [Indexed: 02/07/2023]
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29
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Effect of Phosphorylation on a Human-like Osteopontin Peptide. Biophys J 2017; 112:1586-1596. [PMID: 28445750 PMCID: PMC5406370 DOI: 10.1016/j.bpj.2017.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 02/25/2017] [Accepted: 03/06/2017] [Indexed: 12/22/2022] Open
Abstract
The last decade established that the dynamic properties of the phosphoproteome are central to function and its modulation. The temporal dimension of phosphorylation effects remains nonetheless poorly understood, particularly for intrinsically disordered proteins. Osteopontin, selected for this study due to its key role in biomineralization, is expressed in many species and tissues to play a range of distinct roles. A notable property of highly phosphorylated isoforms of osteopontin is their ability to sequester nanoclusters of calcium phosphate to form a core-shell structure, in a fluid that is supersaturated but stable. In Biology, this process enables soft and hard tissues to coexist in the same organism with relative ease. Here, we extend our understanding of the effect of phosphorylation on a disordered protein, the recombinant human-like osteopontin rOPN. The solution structures of the phosphorylated and unphosphorylated rOPN were investigated by small-angle x-ray scattering and no significant changes were detected on the radius of gyration or maximum interatomic distance. The picosecond-to-nanosecond dynamics of the hydrated powders of the two rOPN forms were further compared by elastic and quasi-elastic incoherent neutron scattering. Phosphorylation was found to block some nanosecond side-chain motions while increasing the flexibility of other side chains on the faster timescale. Phosphorylation can thus selectively change the dynamic behavior of even a highly disordered protein such as osteopontin. Through such an effect on rOPN, phosphorylation can direct allosteric mechanisms, interactions with substrates, cofactors and, in this case, amorphous or crystalline biominerals.
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30
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Mamontov E. Microscopic diffusion in hydrated encysted eggs of brine shrimp. Biochim Biophys Acta Gen Subj 2017; 1861:2382-2390. [PMID: 28549919 DOI: 10.1016/j.bbagen.2017.05.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 05/07/2017] [Accepted: 05/23/2017] [Indexed: 11/29/2022]
Abstract
BACKGROUND We have studied microscopic diffusion of water in fully hydrated encysted eggs of brine shrimp (Artemia). METHODS We have utilized quasielastic neutron scattering. RESULTS Dry eggs of brine shrimp were rehydrated using (1) water without additives, (2) eutectic mixture of water and dimethyl sulfoxide, and (3) a concentrated aqueous solution of lithium chloride. Despite the complexity of the hydrated multicellular organism, measurable microscopic diffusivity of water is rather well defined. Pure hydration water in eggs exhibits freezing temperature depression, whereas hydration water in eggs mixed with dimethyl sulfoxide or lithium chloride does not crystallize at all. CONCLUSIONS The characteristic size of the voids occupied by water or aqueous solvents in hydrated brine shrimp eggs is between 2 and 10nm. Those voids are accessible to co-solvents such as dimethyl sulfoxide and lithium chloride. There is no evidence of intracellular water in the hydrated eggs. GENERAL SIGNIFICANCE The lack of intracellular water in the fully hydrated (but still under arrested development) state must be linked to the unique resilience against adverse environmental factors documented not only for the anhydrous, but also hydrated encysted eggs of brine shrimp.
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Affiliation(s)
- E Mamontov
- Chemical and Engineering Materials Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States.
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31
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Anunciado DB, Nyugen VP, Hurst GB, Doktycz MJ, Urban V, Langan P, Mamontov E, O'Neill H. In Vivo Protein Dynamics on the Nanometer Length Scale and Nanosecond Time Scale. J Phys Chem Lett 2017; 8:1899-1904. [PMID: 28388043 DOI: 10.1021/acs.jpclett.7b00399] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Selectively labeled GroEL protein was produced in living deuterated bacterial cells to enhance its neutron scattering signal above that of the intracellular milieu. Quasi-elastic neutron scattering shows that the in-cell diffusion coefficient of GroEL was (4.7 ± 0.3) × 10-12 m2/s, a factor of 4 slower than its diffusion coefficient in buffer solution. Internal protein dynamics showed a relaxation time of (65 ± 6) ps, a factor of 2 slower compared to the protein in solution. Comparison to the literature suggests that the effective diffusivity of proteins depends on the length and time scale being probed. Retardation of in-cell diffusion compared to the buffer becomes more significant with the increasing probe length scale, suggesting that intracellular diffusion of biomolecules is nonuniform over the cellular volume. The approach outlined here enables investigation of protein dynamics within living cells to open up new lines of research using "in-cell neutron scattering" to study the dynamics of complex biomolecular systems.
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Affiliation(s)
| | | | | | | | | | | | | | - Hugh O'Neill
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee , Knoxville, Tennessee 37996, United States
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32
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Molodenskiy D, Shirshin E, Tikhonova T, Gruzinov A, Peters G, Spinozzi F. Thermally induced conformational changes and protein–protein interactions of bovine serum albumin in aqueous solution under different pH and ionic strengths as revealed by SAXS measurements. Phys Chem Chem Phys 2017. [DOI: 10.1039/c6cp08809k] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Temperature-induced oligomerization of albumin before and after protein melting was studied using SAXS and interpreted in terms of interaction potential.
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Affiliation(s)
| | - Evgeny Shirshin
- Department of Physics
- M.V. Lomonosov Moscow State University
- Moscow
- Russia
| | - Tatiana Tikhonova
- International Laser Center
- M.V. Lomonosov Moscow State University
- Moscow
- Russia
| | | | - Georgy Peters
- National Research Centre “Kurchatov Institute”
- Moscow
- Russia
| | - Francesco Spinozzi
- Università Politecnica delle Marche
- Dipartimento di Scienze della Vita e dell'Ambiente
- Ancona
- Italy
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33
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Roosen-Runge F, Bicout DJ, Barrat JL. Analytical correlation functions for motion through diffusivity landscapes. J Chem Phys 2016; 144:204109. [DOI: 10.1063/1.4950889] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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34
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Fujiwara S, Araki K, Matsuo T, Yagi H, Yamada T, Shibata K, Mochizuki H. Dynamical Behavior of Human α-Synuclein Studied by Quasielastic Neutron Scattering. PLoS One 2016; 11:e0151447. [PMID: 27097022 PMCID: PMC4838215 DOI: 10.1371/journal.pone.0151447] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 02/29/2016] [Indexed: 12/02/2022] Open
Abstract
α-synuclein (αSyn) is a protein consisting of 140 amino acid residues and is abundant in the presynaptic nerve terminals in the brain. Although its precise function is unknown, the filamentous aggregates (amyloid fibrils) of αSyn have been shown to be involved in the pathogenesis of Parkinson's disease, which is a progressive neurodegenerative disorder. To understand the pathogenesis mechanism of this disease, the mechanism of the amyloid fibril formation of αSyn must be elucidated. Purified αSyn from bacterial expression is monomeric but intrinsically disordered in solution and forms amyloid fibrils under various conditions. As a first step toward elucidating the mechanism of the fibril formation of αSyn, we investigated dynamical behavior of the purified αSyn in the monomeric state and the fibril state using quasielastic neutron scattering (QENS). We prepared the solution sample of 9.5 mg/ml purified αSyn, and that of 46 mg/ml αSyn in the fibril state, both at pD 7.4 in D2O. The QENS experiments on these samples were performed using the near-backscattering spectrometer, BL02 (DNA), at the Materials and Life Science Facility at the Japan Accelerator Research Complex, Japan. Analysis of the QENS spectra obtained shows that diffusive global motions are observed in the monomeric state but largely suppressed in the fibril state. However, the amplitude of the side chain motion is shown to be larger in the fibril state than in the monomeric state. This implies that significant solvent space exists within the fibrils, which is attributed to the αSyn molecules within the fibrils having a distribution of conformations. The larger amplitude of the side chain motion in the fibril state than in the monomeric state implies that the fibril state is entropically favorable.
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Affiliation(s)
- Satoru Fujiwara
- Quantum Beam Science Center, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan
- * E-mail:
| | - Katsuya Araki
- Department of Neurology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Tatsuhito Matsuo
- Quantum Beam Science Center, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan
| | - Hisashi Yagi
- Center for Research on Green Sustainable Chemistry, Tottori University, Tottori, Japan
| | - Takeshi Yamada
- Research Center for Neutron Science and Technology, CROSS-Tokai, Tokai, Ibaraki, Japan
| | - Kaoru Shibata
- Neutron Science Section, J-PARC Center, Tokai, Ibaraki, Japan
| | - Hideki Mochizuki
- Department of Neurology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
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35
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Stadler AM, Demmel F, Ollivier J, Seydel T. Picosecond to nanosecond dynamics provide a source of conformational entropy for protein folding. Phys Chem Chem Phys 2016; 18:21527-38. [DOI: 10.1039/c6cp04146a] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Myoglobin can be trapped in fully folded structures, partially folded molten globules, and unfolded states under stable equilibrium conditions.
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Affiliation(s)
- Andreas M. Stadler
- Jülich Centre for Neutron Science JCNS and Institute for Complex Systems ICS
- Forschungszentrum Jülich GmbH
- 52425 Jülich
- Germany
| | | | | | - Tilo Seydel
- Institut Laue-Langevin
- 38042 Grenoble Cedex 9
- France
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