1
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Lang X, Shi L, Zhao Z, Min W. Probing the structure of water in individual living cells. Nat Commun 2024; 15:5271. [PMID: 38902250 PMCID: PMC11190263 DOI: 10.1038/s41467-024-49404-9] [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: 10/16/2023] [Accepted: 06/04/2024] [Indexed: 06/22/2024] Open
Abstract
Water regulates or even governs a wide range of biological processes. Despite its fundamental importance, surprisingly little is known about the structure of intracellular water. Herein we employ a Raman micro-spectroscopy technique to uncover the composition, abundance and vibrational spectra of intracellular water in individual living cells. In three different cell types, we show a small but consistent population (~3%) of non-bulk-like water. It exhibits a weakened hydrogen-bonded network and a more disordered tetrahedral structure. We attribute this population to biointerfacial water located in the vicinity of biomolecules. Moreover, our whole-cell modeling suggests that all soluble (globular) proteins inside cells are surrounded by, on average, one full molecular layer (about 2.6 Angstrom) of biointerfacial water. Furthermore, relative invariance of biointerfacial water is observed among different single cells. Overall, our study not only opens up experimental possibilities of interrogating water structure in vivo but also provides insights into water in life.
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Affiliation(s)
- Xiaoqi Lang
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Lixue Shi
- Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Zhilun Zhao
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Wei Min
- Department of Chemistry, Columbia University, New York, NY, 10027, USA.
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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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Matsuura H, Takano K, Shirakashi R. Slow water dynamics in dehydrated human Jurkat T cells evaluated by dielectric spectroscopy with the Bruggeman-Hanai equation. RSC Adv 2023; 13:20934-20940. [PMID: 37441032 PMCID: PMC10334875 DOI: 10.1039/d3ra02892e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023] Open
Abstract
The picosecond orientational dynamics of intracellular water was measured by dielectric spectroscopy, with the aim of revealing the effects of cryoprotective agents (CPAs) on biological cells. As a first step, Jurkat cells (human T lymphocyte cells) suspended in aqueous sucrose solutions of different concentrations ranging from 0.3 M (isotonic) to 0.9 M (hypertonic) were examined at 25 °C with a frequency range up to 43.5 GHz. The Bruggeman-Hanai equation was employed to obtain a cellular dielectric spectrum without extracellular contributions from the measured complex permittivity of the cell suspensions. By analyzing the γ process around 1010 Hz based on the Debye relaxation function, two types of water (bulk-like water and hydration water with slower molecular dynamics) were observed. An increase in the fraction of intracellular slower water was observed in the dehydrated cells which had a highly concentrated environment of biomolecules.
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Affiliation(s)
- Hiroaki Matsuura
- Institute of Industrial Science, The University of Tokyo Meguro Tokyo 153-8505 Japan
- Research Fellow of the Japan Society for the Promotion of Science Chiyoda Tokyo 102-0083 Japan
| | - Kiyoshi Takano
- Institute of Industrial Science, The University of Tokyo Meguro Tokyo 153-8505 Japan
| | - Ryo Shirakashi
- Institute of Industrial Science, The University of Tokyo Meguro Tokyo 153-8505 Japan
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4
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Exploring the Limits of Biological Complexity Amenable to Studies by Incoherent Neutron Spectroscopy. LIFE (BASEL, SWITZERLAND) 2022; 12:life12081219. [PMID: 36013398 PMCID: PMC9410259 DOI: 10.3390/life12081219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/06/2022] [Accepted: 08/09/2022] [Indexed: 11/16/2022]
Abstract
The wavelengths of neutrons available at neutron scattering facilities are comparable with intra- and inter-molecular distances, while their energies are comparable with molecular vibrational energies, making such neutrons highly suitable for studies of molecular-level dynamics. The unmistakable trend in neutron spectroscopy has been towards measurements of systems of greater complexity. Several decades of studies of dynamics using neutron scattering have witnessed a progression from measurements of solids to liquids to protein complexes and biomembranes, which may exhibit properties characteristic of both solids and liquids. Over the last two decades, the frontier of complexity amenable to neutron spectroscopy studies has reached the level of cells. Considering this a baseline for neutron spectroscopy of systems of the utmost biological complexity, we briefly review what has been learned to date from neutron scattering studies at the cellular level and then discuss in more detail the recent strides into neutron spectroscopy of tissues and whole multicellular organisms.
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5
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Marques MPM, Santos IP, Batista de Carvalho ALM, Mamede AP, Martins CB, Figueiredo P, Sarter M, Sakai VG, Batista de Carvalho LAE. Water dynamics in human cancer and non-cancer tissues. Phys Chem Chem Phys 2022; 24:15406-15415. [PMID: 35704895 DOI: 10.1039/d2cp00621a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Normal-to-malignant transformation is a poorly understood process associated with cellular biomechanical properties. These are strongly dependent on the dynamical behaviour of water, known to play a fundamental role in normal cellular activity and in the maintenance of the three-dimensional architecture of the tissue and the functional state of biopolymers. In this study, quasi-elastic neutron scattering was used to probe the dynamical behaviour of water in human cancer specimens and their respective surrounding normal tissue from breast and tongue, as an innovative approach for identifying particular features of malignancy. This methodology has been successfully used by the authors in human cells and was the first study of human tissues by neutron scattering techniques. A larger flexibility was observed for breast versus tongue tissues. Additionally, different dynamics were found for malignant and non-malignant specimens, depending on the tissue: higher plasticity for breast invasive cancer versus the normal, and an opposite effect for tongue. The data were interpreted in the light of two different water populations within the samples: one displaying bulk-like dynamics (extracellular and intracellular/cytoplasmic) and another with constrained flexibility (extracellular/interstitial and intracellular/hydration layers).
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Affiliation(s)
- M P M Marques
- University of Coimbra, Molecular Physical-Chemistry R&D Unit, Department of Chemistry, 3004-535 Coimbra, Portugal. .,University of Coimbra, Department of Life Sciences, 3000-456 Coimbra, Portugal
| | - I P Santos
- University of Coimbra, Molecular Physical-Chemistry R&D Unit, Department of Chemistry, 3004-535 Coimbra, Portugal.
| | - A L M Batista de Carvalho
- University of Coimbra, Molecular Physical-Chemistry R&D Unit, Department of Chemistry, 3004-535 Coimbra, Portugal.
| | - A P Mamede
- University of Coimbra, Molecular Physical-Chemistry R&D Unit, Department of Chemistry, 3004-535 Coimbra, Portugal.
| | - C B Martins
- University of Coimbra, Molecular Physical-Chemistry R&D Unit, Department of Chemistry, 3004-535 Coimbra, Portugal.
| | - P Figueiredo
- Oncology Institute of Coimbra Francisco Gentil, 3000-075 Coimbra, Portugal
| | - M Sarter
- ISIS Neutron and Muon Facility, STFC Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, UK
| | - V García Sakai
- ISIS Neutron and Muon Facility, STFC Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, UK
| | - L A E Batista de Carvalho
- University of Coimbra, Molecular Physical-Chemistry R&D Unit, Department of Chemistry, 3004-535 Coimbra, Portugal.
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6
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Campo MG, Corral GM. Structural, dynamic, and hydration properties of quercetin and its aggregates in solution. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:294001. [PMID: 35472688 DOI: 10.1088/1361-648x/ac6a99] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 04/26/2022] [Indexed: 06/14/2023]
Abstract
Quercetin is a flavonoid present in the human diet with multiple health benefits. Quercetin solutions are inhomogeneous even at very low concentrations due to quercetin's tendency to aggregate. We simulate, using molecular dynamics, three systems of quercetin solutions: infinite dilution, 0.22 M, and 0.46 M. The systems at the two highest concentrations represent regions of the quercetin aggregates, in which the concentration of this molecule is unusually high. We study the behavior of this molecule, its aggregates, and the modifications in the surrounding water. In the first three successive layers of quercetin hydration, the density of water and the hydrogen bonds formations between water molecules are smaller than that of bulk. Quercetin has a hydrophilic surface region that preferentially establishes donor hydrogen bonds with water molecules with relative frequencies from 0.12 to 0.46 at infinite dilution. Also, it has two hydrophobic regions above and below the planes of its rings, whose first hydration layers are further out from quercetin (≈0.3 Å) and their water molecules do not establish hydrogen bonds with it. Water density around the hydrophobic regions is smaller than that of the hydrophilic. Quercetin molecules aggregate inπ-stacking configurations, with a distance of ≈0.37 nm between the planes of their rings, and form bonds between their hydroxyl groups. The formation of quercetin aggregates decreases the hydrogen bonds between quercetin and the surrounding water and produces a subdiffusive behavior in water molecules. Quercetin has a subdiffusive behavior even at infinite dilution, which increases with the number of molecules within the aggregates and the time they remain within them.
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Affiliation(s)
- M G Campo
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Uruguay 151, (6300) Santa Rosa, Argentina
| | - G M Corral
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Uruguay 151, (6300) Santa Rosa, Argentina
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7
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Martins ML, Bordallo HN, Mamontov E. Water Dynamics in Cancer Cells: Lessons from Quasielastic Neutron Scattering. Medicina (B Aires) 2022; 58:medicina58050654. [PMID: 35630072 PMCID: PMC9145030 DOI: 10.3390/medicina58050654] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/04/2022] [Accepted: 05/10/2022] [Indexed: 12/14/2022] Open
Abstract
The severity of the cancer statistics around the globe and the complexity involving the behavior of cancer cells inevitably calls for contributions from multidisciplinary areas of research. As such, materials science became a powerful asset to support biological research in comprehending the macro and microscopic behavior of cancer cells and untangling factors that may contribute to their progression or remission. The contributions of cellular water dynamics in this process have always been debated and, in recent years, experimental works performed with Quasielastic neutron scattering (QENS) brought new perspectives to these discussions. In this review, we address these works and highlight the value of QENS in comprehending the role played by water molecules in tumor cells and their response to external agents, particularly chemotherapy drugs. In addition, this paper provides an overview of QENS intended for scientists with different backgrounds and comments on the possibilities to be explored with the next-generation spectrometers under construction.
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Affiliation(s)
- Murillo L. Martins
- Oak Ridge National Laboratory, Neutron Scattering Division, Oak Ridge, TN 37831, USA
- Correspondence: (M.L.M.); (E.M.)
| | - Heloisa N. Bordallo
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark;
| | - Eugene Mamontov
- Oak Ridge National Laboratory, Neutron Scattering Division, Oak Ridge, TN 37831, USA
- Correspondence: (M.L.M.); (E.M.)
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8
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Increase in the Intracellular Bulk Water Content in the Early Phase of Cell Death of Keratinocytes, Corneoptosis, as Revealed by 65 GHz Near-Field CMOS Dielectric Sensor. Molecules 2022; 27:molecules27092886. [PMID: 35566237 PMCID: PMC9102150 DOI: 10.3390/molecules27092886] [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] [Received: 02/25/2022] [Revised: 04/22/2022] [Accepted: 04/28/2022] [Indexed: 11/16/2022] Open
Abstract
While bulk water and hydration water coexist in cells to support the expression of biological macromolecules, how the dynamics of water molecules, which have long been only a minor role in molecular biology research, relate to changes in cellular states such as cell death has hardly been explored so far due to the lack of evaluation techniques. In this study, we developed a high-precision measurement system that can discriminate bulk water content changes of ±0.02% (0.2 mg/cm3) with single-cell-level spatial resolution based on a near-field CMOS dielectric sensor operating at 65 GHz. We applied this system to evaluate the temporal changes in the bulk water content during the cell death process of keratinocytes, called corneoptosis, using isolated SG1 (first layer of stratum granulosum) cells in vitro. A significant irreversible increase in the bulk water content was observed approximately 1 h before membrane disruption during corneoptosis, which starts with cytoplasmic high Ca2+ signal. These findings suggest that the calcium flux may have a role in triggering the increase in the bulk water content in SG1 cells. Thus, our near-field CMOS dielectric sensor provides a valuable tool to dissect the involvement of water molecules in the various events that occur in the cell.
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9
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Meuwly M, Karplus M. The functional role of the hemoglobin-water interface. Mol Aspects Med 2021; 84:101042. [PMID: 34756740 DOI: 10.1016/j.mam.2021.101042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/27/2021] [Indexed: 02/06/2023]
Abstract
The interface between hemoglobin (Hb) and its environment, in particular water, is of great physiological relevance. Here, results from in vitro, in vivo, and computational experiments (molecular dynamics simulations) are summarized and put into perspective. One of the main findings from the computations is that the stability of the deoxy, ligand-free T-state (T0) can be stabilized relative to the deoxy R-state (R0) only in sufficiently large simulation boxes for the hydrophobic effect to manifest itself. This effect directly influences protein stability and is operative also under physiological conditions. Furthermore, molecular simulations provide a dynamical interpretation of the Perutz model for Hb function. Results from experiments using higher protein concentrations and realistic cellular environments are also discussed. One of the next great challenges for computational studies, which as we show is likely to be taken up in the near future, is to provide a molecular-level understanding of the dynamics of proteins in such crowded environments.
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Affiliation(s)
- Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056, Basel, Switzerland; Department of Chemistry, Brown University, Providence RI, USA.
| | - Martin Karplus
- Department of Chemistry, Harvard University, USA; Laboratoire de Chimie Biophysique, ISIS, Université de Strasbourg, 67000, Strasbourg, France.
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10
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Latypova L, Puzenko A, Poluektov Y, Anashkina A, Petrushanko I, Bogdanova A, Feldman Y. Hydration of methemoglobin studied by in silico modeling and dielectric spectroscopy. J Chem Phys 2021; 155:015101. [PMID: 34241395 DOI: 10.1063/5.0054697] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The hemoglobin concentration of 35 g/dl of human red blood cells is close to the solubility threshold. Using microwave dielectric spectroscopy, we have assessed the amount of water associated with hydration shells of methemoglobin as a function of its concentration in the presence or absence of ions. We estimated water-hemoglobin interactions to interpret the obtained data. Within the concentration range of 5-10 g/dl of methemoglobin, ions play an important role in defining the free-to-bound water ratio competing with hemoglobin to recruit water molecules for the hydration shell. At higher concentrations, hemoglobin is a major contributor to the recruitment of water to its hydration shell. Furthermore, the amount of bound water does not change as the hemoglobin concentration is increased from 15 to 30 g/dl, remaining at the level of ∼20% of the total intracellular water pool. The theoretical evaluation of the ratio of free and bound water for the hemoglobin concentration in the absence of ions corresponds with the experimental results and shows that the methemoglobin molecule binds about 1400 water molecules. These observations suggest that within the concentration range close to the physiological one, hemoglobin molecules are so close to each other that their hydration shells interact. In this case, the orientation of the hemoglobin molecules is most likely not stochastic, but rather supports partial neutralization of positive and negative charges at the protein surface. Furthermore, deformation of the red blood cell shape results in the rearrangement of these structures.
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Affiliation(s)
- Larisa Latypova
- Department of Applied Physics, The Hebrew University of Jerusalem, Givat Ram 91904, Israel
| | - Alexander Puzenko
- Department of Applied Physics, The Hebrew University of Jerusalem, Givat Ram 91904, Israel
| | - Yuri Poluektov
- Engelhart Institute of Molecular Biology, Russian Academy of Science, Vavilov St. 32, 119991 Moscow, Russia
| | - Anastasia Anashkina
- Engelhart Institute of Molecular Biology, Russian Academy of Science, Vavilov St. 32, 119991 Moscow, Russia
| | - Irina Petrushanko
- Engelhart Institute of Molecular Biology, Russian Academy of Science, Vavilov St. 32, 119991 Moscow, Russia
| | - Anna Bogdanova
- Red Blood Cell Research Group, Institute of Veterinary Physiology, University of Zürich, Winterthurerstrasse 260, CH-8057 Zürich, Switzerland
| | - Yuri Feldman
- Department of Applied Physics, The Hebrew University of Jerusalem, Givat Ram 91904, Israel
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11
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Lang X, Welsher K. Mapping solvation heterogeneity in live cells by hyperspectral stimulated Raman scattering microscopy. J Chem Phys 2020; 152:174201. [PMID: 32384848 DOI: 10.1063/1.5141422] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Water provides a dynamic matrix in which all biochemical processes occur in living organisms. The structure and dynamics of intracellular water constitute the cornerstone for understanding all aspects of cellular function. Fundamentally, direct visualization of subcellular solvation heterogeneity is essential but remains challenging with commonly used nuclear magnetic resonance methods due to poor spatial resolution. To explore this question, we demonstrate a vibrational-shift imaging approach by combining the spectral-focusing hyperspectral stimulated Raman scattering technique with an environmentally sensitive nitrile probe. The sensing ability of a near-infrared nitrile-containing molecule is validated in the solution phase, microscopic droplets, and cellular environments. Finally, we quantitatively measure the subcellular solvation variance between the cytoplasm (29.5%, S.E. 1.8%) and the nucleus (57.3%, S.E. 1.0%), which is in good agreement with previous studies. This work sheds light on heterogeneous solvation in live systems using coherent Raman microscopy and opens up new avenues to explore environmental variance in complex systems with high spatiotemporal resolution.
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Affiliation(s)
- Xiaoqi Lang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Kevin Welsher
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
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12
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Li R, Liu Z, Li L, Huang J, Yamada T, Sakai VG, Tan P, Hong L. Anomalous sub-diffusion of water in biosystems: From hydrated protein powders to concentrated protein solution to living cells. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2020; 7:054703. [PMID: 33094127 PMCID: PMC7556885 DOI: 10.1063/4.0000036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 09/22/2020] [Indexed: 06/11/2023]
Abstract
Water is essential to life and its translational motion in living systems mediates various biological processes, including transportation of function-required ingredients and facilitating the interaction between biomacromolecules. By combining neutron scattering and isotopic labeling, the present work characterizes translational motion of water on a biomolecular surface, in a range of systems: a hydrated protein powder, a concentrated protein solution, and in living Escherichia coli (E. coli) cells. Anomalous sub-diffusion of water is observed in all samples, which is alleviated upon increasing the water content. Complementary molecular dynamics simulations and coarse-grained numerical modeling demonstrated that the sub-diffusive behavior results from the heterogeneous distribution of microscopic translational mobility of interfacial water. Moreover, by comparing the experimental results measured on E. coli cells with those from a concentrated protein solution with the same amount of water, we show that water in the two samples has a similar average mobility, however the underlying distribution of motion is more heterogeneous in the living cell.
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Affiliation(s)
| | | | - Like Li
- Zhiyuan College, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Juan Huang
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Takeshi Yamada
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society, Ibaraki 319-1106, Japan
| | - Victoria García Sakai
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX, United Kingdom
| | - Pan Tan
- Authors to whom correspondence should be addressed: and
| | - Liang Hong
- Authors to whom correspondence should be addressed: and
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13
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Molecular dynamics in cells: A neutron view. Biochim Biophys Acta Gen Subj 2020; 1864:129475. [DOI: 10.1016/j.bbagen.2019.129475] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/01/2019] [Accepted: 11/05/2019] [Indexed: 11/21/2022]
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14
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Marques MPM, Batista de Carvalho ALM, Mamede AP, Rudić S, Dopplapudi A, García Sakai V, Batista de Carvalho LAE. Intracellular water as a mediator of anticancer drug action. INT REV PHYS CHEM 2020. [DOI: 10.1080/0144235x.2020.1700083] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- M. P. M. Marques
- Unidade de I&D Química-Física Molecular, Department of Chemistry, University of Coimbra, Coimbra, Portugal
- Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | | | - A. P. Mamede
- Unidade de I&D Química-Física Molecular, Department of Chemistry, University of Coimbra, Coimbra, Portugal
| | - S. Rudić
- STFC Rutherford Appleton Laboratory, ISIS Facility, Chilton, Didcot, UK
| | - A. Dopplapudi
- STFC Rutherford Appleton Laboratory, ISIS Facility, Chilton, Didcot, UK
| | - V. García Sakai
- STFC Rutherford Appleton Laboratory, ISIS Facility, Chilton, Didcot, UK
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15
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Golub M, Moldenhauer M, Schmitt FJ, Lohstroh W, Maksimov EG, Friedrich T, Pieper J. Solution Structure and Conformational Flexibility in the Active State of the Orange Carotenoid Protein. Part II: Quasielastic Neutron Scattering. J Phys Chem B 2019; 123:9536-9545. [PMID: 31550157 DOI: 10.1021/acs.jpcb.9b05073] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Orange carotenoid proteins (OCPs), which are protecting cyanobacterial light-harvesting antennae from photodamage, undergo a pronounced structural change upon light absorption. In addition, the active state is anticipated to boost a significantly higher molecular flexibility similar to a "molten globule" state. Here, we used quasielastic neutron scattering to directly characterize the vibrational and conformational molecular dynamics of OCP in its ground and active states, respectively, on the picosecond time scale. At a temperature of 100 K, we observe mainly (vibronic) inelastic features with peak energies at 5 and 6 meV (40 and 48 cm-1, respectively). At physiological temperatures, however, two (Lorentzian) quasielastic components represent localized protein motions, that is, stochastic structural fluctuations of protein side chains between various conformational substates of the protein. Global diffusion of OCP is not observed on the given time scale. The slower Lorentzian component is affected by illumination and can be well-characterized by a jump-diffusion model. While the jump diffusion constant D is (2.82 ± 0.01) × 10-5 cm2/s at 300 K in the ground state, it is increased by ∼20% to (3.48 ± 0.01) × 10-5 cm2/s in the active state, revealing a strong enhancement of molecular mobility. The increased mobility is also reflected in the average atomic mean square displacement ⟨u2⟩; we determine a ⟨u2⟩ of 1.47 ± 0.05 Å in the ground state, but 1.86 ± 0.05 Å in the active state (at 300 K). This effect is assigned to two factors: (i) the elongated structure of the active state with two widely separated protein domains is characterized by a larger number of surface residues with a concomitantly higher degree of motional freedom and (ii) a larger number of hydration water molecules bound at the surface of the protein. We thus conclude that the active state of the orange carotenoid protein displays an enhanced conformational dynamics. The higher degree of flexibility may provide additional channels for nonradiative decay so that harmful excess energy can be more efficiently converted to heat.
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Affiliation(s)
- Maksym Golub
- Institute of Physics , University of Tartu , 50411 Tartu , Estonia
| | - Marcus Moldenhauer
- Technische Universität Berlin , Institute of Chemistry, Physical Chemistry , 10623 Berlin , Germany
| | - Franz-Josef Schmitt
- Technische Universität Berlin , Institute of Chemistry, Physical Chemistry , 10623 Berlin , Germany
| | - Wiebke Lohstroh
- Heinz Maier-Leibnitz Zentrum , Technische Universität München , Garching , Germany
| | - Eugene G Maksimov
- Department of Biophysics , M. V. Lomonosov Moscow State University , Moscow , Russia
| | - Thomas Friedrich
- Technische Universität Berlin , Institute of Chemistry, Physical Chemistry , 10623 Berlin , Germany
| | - Jörg Pieper
- Institute of Physics , University of Tartu , 50411 Tartu , Estonia
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16
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Natali F, Dolce C, Peters J, Stelletta C, Demé B, Ollivier J, Leduc G, Cupane A, Barbier EL. Brain lateralization probed by water diffusion at the atomic to micrometric scale. Sci Rep 2019; 9:14694. [PMID: 31604980 PMCID: PMC6789030 DOI: 10.1038/s41598-019-51022-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 09/23/2019] [Indexed: 01/27/2023] Open
Abstract
Combined neutron scattering and diffusion nuclear magnetic resonance experiments have been used to reveal significant interregional asymmetries (lateralization) in bovine brain hemispheres in terms of myelin arrangement and water dynamics at micron to atomic scales. Thicker myelin sheaths were found in the left hemisphere using neutron diffraction. 4.7 T dMRI and quasi-elastic neutron experiments highlighted significant differences in the properties of water dynamics in the two hemispheres. The results were interpreted in terms of hemisphere-dependent cellular composition (number of neurons, cell distribution, etc.) as well as specificity of neurological functions (such as preferential networking).
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Affiliation(s)
- F Natali
- Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, 38042, Grenoble cedex 9, France.
- CNR-IOM, OGG, 71 avenue des Martyrs, CS 20156, 38042, Grenoble cedex 9, France.
| | - C Dolce
- Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, 38042, Grenoble cedex 9, France
- University Grenoble Alpes, LiPhy, 140 rue de la physique, 38402, Saint Martin d'Hères, France
- Department of Physics and Chemistry, University of Palermo, via Archirafi 36, 90123, Palermo, Italy
| | - J Peters
- Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, 38042, Grenoble cedex 9, France
- University Grenoble Alpes, LiPhy, 140 rue de la physique, 38402, Saint Martin d'Hères, France
| | - C Stelletta
- Department of Animal Med., Production and Health, University of Padova, Viale dell'Università 16, 35020, Agripolis, Legnaro, Italy
| | - B Demé
- Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, 38042, Grenoble cedex 9, France
| | - J Ollivier
- Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, 38042, Grenoble cedex 9, France
| | - G Leduc
- Biomedical Facility, ESRF, 71 avenue des Martyrs, CS 20156, 38042, Grenoble cedex 9, France
| | - A Cupane
- Department of Physics and Chemistry, University of Palermo, via Archirafi 36, 90123, Palermo, Italy
| | - E L Barbier
- University Grenoble Alpes, Inserm, U1216, Grenoble Institut Neurosciences, 38000, Grenoble, France
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17
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Laulumaa S, Koza MM, Seydel T, Kursula P, Natali F. A Quasielastic Neutron Scattering Investigation on the Molecular Self-Dynamics of Human Myelin Protein P2. J Phys Chem B 2019; 123:8178-8185. [PMID: 31483648 DOI: 10.1021/acs.jpcb.9b05320] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The human myelin protein P2 is a membrane binding protein believed to maintain correct lipid composition and organization in peripheral nerve myelin. Its function is related to its ability to stack membranes, and this function can be enhanced by the P38G mutation, whereby the overall protein structure does not change but the molecular dynamics increase. Mutations in P2 are linked to human peripheral neuropathy. Here, the dynamics of wild-type P2 and the P38G variant were studied using quasielastic neutron scattering on time scales from 10 ps to 1 ns at 300 K. The results suggest that the mutant protein dynamics are increased on both the fastest and the slowest measured time scales, by increasing the dynamics amplitude and/or the portion of atoms participating in the movement.
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Affiliation(s)
- Saara Laulumaa
- Faculty of Biochemistry and Molecular Medicine and Biocenter Oulu , University of Oulu , Oulu , Finland.,European Spallation Source , Lund , Sweden
| | | | | | - Petri Kursula
- Faculty of Biochemistry and Molecular Medicine and Biocenter Oulu , University of Oulu , Oulu , Finland.,Department of Biomedicine , University of Bergen , Bergen , Norway
| | - Francesca Natali
- Institut Laue-Langevin , Grenoble , France.,CNR-IOM, OGG , Grenoble , France
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18
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Natali F, Dolce C, Peters J, Stelletta C, Demé B, Ollivier J, Boehm M, Leduc G, Piazza I, Cupane A, Barbier EL. Anomalous water dynamics in brain: a combined diffusion magnetic resonance imaging and neutron scattering investigation. J R Soc Interface 2019; 16:20190186. [PMID: 31409238 PMCID: PMC6731513 DOI: 10.1098/rsif.2019.0186] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 07/15/2019] [Indexed: 12/31/2022] Open
Abstract
Water diffusion is an optimal tool for investigating the architecture of brain tissue on which modern medical diagnostic imaging techniques rely. However, intrinsic tissue heterogeneity causes systematic deviations from pure free-water diffusion behaviour. To date, numerous theoretical and empirical approaches have been proposed to explain the non-Gaussian profile of this process. The aim of this work is to shed light on the physics piloting water diffusion in brain tissue at the micrometre-to-atomic scale. Combined diffusion magnetic resonance imaging and first pioneering neutron scattering experiments on bovine brain tissue have been performed in order to probe diffusion distances up to macromolecular separation. The coexistence of free-like and confined water populations in brain tissue extracted from a bovine right hemisphere has been revealed at the micrometre and atomic scale. The results are relevant for improving the modelling of the physics driving intra- and extracellular water diffusion in brain, with evident benefit for the diffusion magnetic resonance imaging technique, nowadays widely used to diagnose, at the micrometre scale, brain diseases such as ischemia and tumours.
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Affiliation(s)
- F. Natali
- Institut Laue-Langevin, Grenoble Cedex 9, France
- CNR-IOM, OGG, Grenoble Cedex 9, France
| | - C. Dolce
- Institut Laue-Langevin, Grenoble Cedex 9, France
- CNRS, Univ. Grenoble Alpes, LIPhy, 38000 Grenoble, France
- Department of Physics and Chemistry, University of Palermo, Palermo, Italy
| | - J. Peters
- Institut Laue-Langevin, Grenoble Cedex 9, France
- CNRS, Univ. Grenoble Alpes, LIPhy, 38000 Grenoble, France
| | - C. Stelletta
- Department of Animal Medicine, Production and Health, University of Padova, Padova, Italy
| | - B. Demé
- Institut Laue-Langevin, Grenoble Cedex 9, France
| | - J. Ollivier
- Institut Laue-Langevin, Grenoble Cedex 9, France
| | - M. Boehm
- Institut Laue-Langevin, Grenoble Cedex 9, France
| | - G. Leduc
- Biomedical Facility, ESRF, Grenoble, France
| | - I. Piazza
- Institut Laue-Langevin, Grenoble Cedex 9, France
- Department of Physics and Chemistry, University of Palermo, Palermo, Italy
| | - A. Cupane
- Department of Physics and Chemistry, University of Palermo, Palermo, Italy
| | - E. L. Barbier
- Grenoble Institut Neurosciences, University of Grenoble Alpes, Inserm, U1216, 38000 Grenoble, France
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19
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Mamontov E, Osti NC, Tyagi M. Temperature dependence of nanoscale dynamic processes measured in living millipedes by high resolution inelastic and elastic neutron scattering. Sci Rep 2019; 9:11646. [PMID: 31406234 PMCID: PMC6691110 DOI: 10.1038/s41598-019-48270-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 08/01/2019] [Indexed: 12/12/2022] Open
Abstract
We have used high energy-resolution neutron scattering to probe nanoscale dynamic processes in living millipedes (Narceus americanus). We have measured the temperature dependence of the intensity of scattered neutrons that do not exchange energy with the living samples on the 1.5 ns time scale, thereby excluding the signal from the highly mobile intra- and extra-cellular bulk-like aqueous constituents in the sample. This measured “elastic” scattering intensity exhibits a non-monotonic temperature dependence, with a noticeable systematic decrease detected between 295 and 303 K on warming up from 283 to 310 K. This decrease demonstrates an excellent inverse correlation with the non-monotonic, as a function of temperature, increase in the slow diffusivity previously observed in planarian flatworms and housefly larvae. This correlation suggests the existence of a biological mechanism, possibly common between different classes (Insects and Myriapods) and even phyla (Arthropods and Platyhelminthes), that dampens the slow nanoscopic dynamics in ectothermic organisms in response to the temperature of the environment exceeding the physiologically optimal range.
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Affiliation(s)
- Eugene Mamontov
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA.
| | - Naresh C Osti
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Madhusudan Tyagi
- NIST Center for Neutron Research and University of Maryland, Gaithersburg, Maryland, 20899, USA
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20
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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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21
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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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22
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Abstract
The structure and function of biomolecules are strongly influenced by their hydration shells. Structural fluctuations and molecular excitations of hydrating water molecules cover a broad range in space and time, from individual water molecules to larger pools and from femtosecond to microsecond time scales. Recent progress in theory and molecular dynamics simulations as well as in ultrafast vibrational spectroscopy has led to new and detailed insight into fluctuations of water structure, elementary water motions, electric fields at hydrated biointerfaces, and processes of vibrational relaxation and energy dissipation. Here, we review recent advances in both theory and experiment, focusing on hydrated DNA, proteins, and phospholipids, and compare dynamics in the hydration shells to bulk water.
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Affiliation(s)
- Damien Laage
- École
Normale Supérieure, PSL Research University, UPMC Univ Paris
06, CNRS, Département de Chimie,
PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne
Universités, UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
| | - Thomas Elsaesser
- Max-Born-Institut
für Nichtlineare Optik und Kurzzeitspektroskopie, D-12489 Berlin, Germany
| | - James T. Hynes
- École
Normale Supérieure, PSL Research University, UPMC Univ Paris
06, CNRS, Département de Chimie,
PASTEUR, 24 rue Lhomond, 75005 Paris, France
- Sorbonne
Universités, UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France
- Department
of Chemistry and Biochemistry, University
of Colorado, Boulder, Colorado 80309, United
States
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23
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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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24
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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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25
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Marques MPM, Batista de Carvalho ALM, Sakai VG, Hatter L, Batista de Carvalho LAE. Intracellular water – an overlooked drug target? Cisplatin impact in cancer cells probed by neutrons. Phys Chem Chem Phys 2017; 19:2702-2713. [DOI: 10.1039/c6cp05198g] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Intracellular water as a secondary pharmacological target?
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Affiliation(s)
- M. P. M. Marques
- Unidade de I&D Química-Física Molecular
- Dep. of Chemistry
- R. Larga
- Univ. Coimbra
- 3004-535 Coimbra
| | | | - V. Garcia Sakai
- ISIS Facility
- STFC Rutherford Appleton Laboratory
- Chilton
- Didcot
- UK
| | - L. Hatter
- Research Complex at Harwell
- STFC Rutherford Appleton Laboratory
- Chilton
- Didcot
- UK
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26
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High protein flexibility and reduced hydration water dynamics are key pressure adaptive strategies in prokaryotes. Sci Rep 2016; 6:32816. [PMID: 27595789 PMCID: PMC5011708 DOI: 10.1038/srep32816] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/12/2016] [Indexed: 12/12/2022] Open
Abstract
Water and protein dynamics on a nanometer scale were measured by quasi-elastic neutron scattering in the piezophile archaeon Thermococcus barophilus and the closely related pressure-sensitive Thermococcus kodakarensis, at 0.1 and 40 MPa. We show that cells of the pressure sensitive organism exhibit higher intrinsic stability. Both the hydration water dynamics and the fast protein and lipid dynamics are reduced under pressure. In contrast, the proteome of T. barophilus is more pressure sensitive than that of T. kodakarensis. The diffusion coefficient of hydration water is reduced, while the fast protein and lipid dynamics are slightly enhanced with increasing pressure. These findings show that the coupling between hydration water and cellular constituents might not be simply a master-slave relationship. We propose that the high flexibility of the T. barophilus proteome associated with reduced hydration water may be the keys to the molecular adaptation of the cells to high hydrostatic pressure.
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27
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Neutrons describe ectoine effects on water H-bonding and hydration around a soluble protein and a cell membrane. Sci Rep 2016; 6:31434. [PMID: 27527336 PMCID: PMC4985633 DOI: 10.1038/srep31434] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 07/21/2016] [Indexed: 01/09/2023] Open
Abstract
Understanding adaptation to extreme environments remains a challenge of high biotechnological potential for fundamental molecular biology. The cytosol of many microorganisms, isolated from saline environments, reversibly accumulates molar concentrations of the osmolyte ectoine to counterbalance fluctuating external salt concentrations. Although they have been studied extensively by thermodynamic and spectroscopic methods, direct experimental structural data have, so far, been lacking on ectoine-water-protein interactions. In this paper, in vivo deuterium labeling, small angle neutron scattering, neutron membrane diffraction and inelastic scattering are combined with neutron liquids diffraction to characterize the extreme ectoine-containing solvent and its effects on purple membrane of H. salinarum and E. coli maltose binding protein. The data reveal that ectoine is excluded from the hydration layer at the membrane surface and does not affect membrane molecular dynamics, and prove a previous hypothesis that ectoine is excluded from a monolayer of dense hydration water around the soluble protein. Neutron liquids diffraction to atomic resolution shows how ectoine enhances the remarkable properties of H-bonds in water—properties that are essential for the proper organization, stabilization and dynamics of biological structures.
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28
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Yoshida K, Tashiro A, Yamaguchi T. Thermal properties and hydration structure of poly-l-lysine, polyglycine, and lysozyme. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2015.08.048] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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29
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Zhu H, Guo Z, Liu W. Biomimetic water-collecting materials inspired by nature. Chem Commun (Camb) 2016; 52:3863-79. [PMID: 26898232 DOI: 10.1039/c5cc09867j] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Nowadays, water shortage is a severe issue all over the world, especially in some arid and undeveloped areas. Interestingly, a variety of natural creatures can collect water from fog, which can provide a source of inspiration to develop novel and functional water-collecting materials. Recently, as an increasingly hot research topic, bioinspired materials with the water collection ability have captured vast scientific attention in both practical applications and fundamental research studies. In this review, we summarize the mechanisms of water collection in various natural creatures and present the fabrications, functions, applications, and new developments of bioinspired materials in recent years. The theoretical basis related to the phenomenon of water collection containing wetting behaviors and water droplet transportations is described in the beginning, i.e., the Young's equation, Wenzel model, Cassie model, surface energy gradient model and Laplace pressure equation. Then, the water collection mechanisms of three typical and widely researched natural animals and plants are discussed and their corresponding bioinspired materials are simultaneously detailed, which are cactus, spider, and desert beetles, respectively. This is followed by introducing another eight animals and plants (butterfly, shore birds, wheat awns, green bristlegrass, the Cotula fallax plant, Namib grass, green tree frogs and Australian desert lizards) that are rarely reported, exhibiting water collection properties or similar water droplet transportation. Finally, conclusions and outlook concerning the future development of bioinspired fog-collecting materials are presented.
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Affiliation(s)
- Hai Zhu
- Hubei Collaborative Innovation Centre for Advanced Organic Chemical Materials and Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan 430062, People's Republic of China.
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30
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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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31
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Monkenbusch M, Stadler A, Biehl R, Ollivier J, Zamponi M, Richter D. Fast internal dynamics in alcohol dehydrogenase. J Chem Phys 2015; 143:075101. [DOI: 10.1063/1.4928512] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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32
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Calligari PA, Calandrini V, Ollivier J, Artero JB, Härtlein M, Johnson M, Kneller GR. Adaptation of Extremophilic Proteins with Temperature and Pressure: Evidence from Initiation Factor 6. J Phys Chem B 2015; 119:7860-73. [PMID: 25996652 DOI: 10.1021/acs.jpcb.5b02034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work, we study dynamical properties of an extremophilic protein, Initiation Factor 6 (IF6), produced by the archeabacterium Methanocaldococcus jannascii, which thrives close to deep-sea hydrothermal vents where temperatures reach 80 °C and the pressure is up to 750 bar. Molecular dynamics simulations (MD) and quasi-elastic neutron scattering (QENS) measurements give new insights into the dynamical properties of this protein with respect to its eukaryotic and mesophilic homologue. Results obtained by MD are supported by QENS data and are interpreted within the framework of a fractional Brownian dynamics model for the characterization of protein relaxation dynamics. IF6 from M. jannaschii at high temperature and pressure shares similar flexibility with its eukaryotic homologue from S. cerevisieae under ambient conditions. This work shows for the first time, to our knowledge, that the very common pattern of corresponding states for thermophilic protein adaptation can be extended to thermo-barophilic proteins. A detailed analysis of dynamic properties and of local structural fluctuations reveals a complex pattern for "corresponding" structural flexibilities. In particular, in the case of IF6, the latter seems to be strongly related to the entropic contribution given by an additional, C-terminal, 20 amino-acid tail which is evolutionary conserved in all mesophilic IF6s.
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Affiliation(s)
- Paolo A Calligari
- †SISSA, International School for Advanced Studies, via Bonomea 265, 34136 Trieste, Italy
| | - Vania Calandrini
- ‡Computational Biophysics, German Research School for Simulation Sciences, Jülich, Germany
| | - Jacques Ollivier
- §Institut Laue-Langevin, 6 Rue Jules Horowitz, BP 156, 38042 Grenoble Cedex, France
| | - Jean-Baptiste Artero
- §Institut Laue-Langevin, 6 Rue Jules Horowitz, BP 156, 38042 Grenoble Cedex, France
| | - Michael Härtlein
- §Institut Laue-Langevin, 6 Rue Jules Horowitz, BP 156, 38042 Grenoble Cedex, France
| | - Mark Johnson
- §Institut Laue-Langevin, 6 Rue Jules Horowitz, BP 156, 38042 Grenoble Cedex, France
| | - Gerald R Kneller
- ∥Centre de Biophysique Moléculaire, CNRS UPR 4301, Rue Charles Sadron, F-45071 Orléans Cedex 2, France.,⊥Synchrotron Soleil, L'Orme de Merisiers, BP 48, 91192 Gif-sur-Yvette, France.,#Université de Orléans, Chateau de la Source-Av. du Parc Floral, 45067 Orléans, France
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33
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Martinez N, Natali F, Peters J. mQfit, a new program for analyzing quasi-elastic neutron scattering data. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20158303010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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34
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Luby-Phelps K. The physical chemistry of cytoplasm and its influence on cell function: an update. Mol Biol Cell 2014; 24:2593-6. [PMID: 23989722 PMCID: PMC3756912 DOI: 10.1091/mbc.e12-08-0617] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
From the point of view of intermolecular interactions, the cytoplasmic space is more like a crowded party in a house full of furniture than a game of tag in an empty field. Understanding the physical chemical properties of cytoplasm is thus of key importance for understanding cellular function. This article attempts to provide an entrée into the current literature on this subject and offers some general guidelines for thinking about intracellular biochemistry.
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Affiliation(s)
- Kate Luby-Phelps
- Department of Cell Biology, UT Southwestern Medical School, Dallas, TX 75390, USA.
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Vauclare P, Madern D, Girard E, Gabel F, Zaccai G, Franzetti B. New insights into microbial adaptation to extreme saline environments. BIO WEB OF CONFERENCES 2014. [DOI: 10.1051/bioconf/20140202001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Sebastiani F, Orecchini A, Paciaroni A, Jasnin M, Zaccai G, Moulin M, Haertlein M, De Francesco A, Petrillo C, Sacchetti F. Collective THz dynamics in living Escherichia coli cells. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2013.06.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Fujiwara S, Plazanet M, Oda T. Coupling of the hydration water dynamics and the internal dynamics of actin detected by quasielastic neutron scattering. Biochem Biophys Res Commun 2013; 431:542-6. [PMID: 23321308 DOI: 10.1016/j.bbrc.2013.01.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 01/07/2013] [Indexed: 11/17/2022]
Abstract
In order to characterize dynamics of water molecules around F-actin and G-actin, quasielastic neutron scattering experiments were performed on powder samples of F-actin and G-actin, hydrated either with D(2)O or H(2)O, at hydration ratios of 0.4 and 1.0. By combined analysis of the quasielastic neutron scattering spectra, the parameter values characterizing the dynamics of the water molecules in the first hydration layer and those of the water molecules outside of the first layer were obtained. The translational diffusion coefficients (D(T)) of the hydration water in the first layer were found to be 1.2×10(-5) cm(2)/s and 1.7×10(-5) cm(2)/s for F-actin and G-actin, respectively, while that for bulk water was 2.8×10(-5) cm(2)/s. The residence times were 6.6 ps and 5.0 ps for F-actin and G-actin, respectively, while that for bulk water was 0.62 ps. These differences between F-actin and G-actin, indicating that the hydration water around G-actin is more mobile than that around F-actin, are in concert with the results of the internal dynamics of F-actin and G-actin, showing that G-actin fluctuates more rapidly than F-actin. This implies that the dynamics of the hydration water is coupled to the internal dynamics of the actin molecules. The D(T) values of the water molecules outside of the first hydration layer were found to be similar to that of bulk water though the residence times are strongly affected by the first hydration layer. This supports the recent observation on intracellular water that shows bulk-like behavior.
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Affiliation(s)
- Satoru Fujiwara
- Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan.
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Combet S, Zanotti JM. Further evidence that interfacial water is the main "driving force" of protein dynamics: a neutron scattering study on perdeuterated C-phycocyanin. Phys Chem Chem Phys 2012; 14:4927-34. [PMID: 22388956 DOI: 10.1039/c2cp23725c] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The fundamental role of hydration water (also called interfacial water) is widely recognized in protein flexibility, especially in the existence of the so-called protein "dynamical transition" at around 220 K. In the present study, we take advantage of perdeuterated C-phycocyanin (CPC) and elastic incoherent neutron scattering (EINS) to distinguish between protein dynamics and interfacial water dynamics. Powders of hydrogenated (hCPC) and perdeuterated (dCPC) CPC protein have been hydrated, respectively, with D(2)O or H(2)O and measured by EINS to separately probe protein dynamics (hCPC/D(2)O) and water dynamics (dCPC/H(2)O) at different time- and length-scales. We find that "fast" (<20 ps) local mean-square displacements (MSD) of both protein and interfacial water coincide all along the temperature range, with the same dynamical transition temperature at ~220 K. On higher resolution (<400 ps), two different types of motions can be separated: (i) localized motions with the same amplitude for CPC and hydration water and two transitions at ~170 and ~240 K for both; (ii) large scale fluctuations exhibiting for both water molecules and CPC protein a single transition at ~240 K, with a significantly higher amplitude for the interfacial water than for CPC. Moreover, by comparing these motions with bulk water MSD measured under the same conditions, we show no coupling between bulk water dynamics and protein dynamics all along the temperature range. These results show that interfacial water is the main "driving force" governing both local and large scale motions in proteins.
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Affiliation(s)
- Sophie Combet
- Laboratoire Léon-Brillouin, UMR 12 CEA/CNRS, bât. 563, CEA-Saclay, F-91191 Gif-sur-Yvette, France.
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Orecchini A, Sebastiani F, Jasnin M, Paciaroni A, Francesco AD, Petrillo C, Moulin M, Haertlein M, Zaccai G, Sacchetti F. Collective Dynamics of Intracellular Water in Living Cells. ACTA ACUST UNITED AC 2012. [DOI: 10.1088/1742-6596/340/1/012091] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Stadler AM, van Eijck L, Demmel F, Artmann G. Macromolecular dynamics in red blood cells investigated using neutron spectroscopy. J R Soc Interface 2010; 8:590-600. [PMID: 20739313 DOI: 10.1098/rsif.2010.0306] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We present neutron scattering measurements on the dynamics of haemoglobin (Hb) in human red blood cells (RBCs) in vivo. Global and internal Hb dynamics were measured in the ps to ns time and Å length scales using quasi-elastic neutron backscattering spectroscopy. We observed the cross over from global Hb short-time to long-time self-diffusion. Both short- and long-time diffusion coefficients agree quantitatively with predicted values from the hydrodynamic theory of non-charged hard-sphere suspensions when a bound water fraction of around 0.23 gram H(2)O per gram Hb is taken into account. The higher amount of water in the cells facilitates internal protein fluctuations in the ps time scale when compared with fully hydrated Hb powder. Slower internal dynamics of Hb in RBCs in the ns time range were found to be rather similar to results obtained with fully hydrated protein powders, solutions and Escherichia coli cells.
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Stadler AM. Dynamics in Biological Systems as seen by QENS. Z PHYS CHEM 2010. [DOI: 10.1524/zpch.2010.6099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Quasielastic incoherent neutron scattering is a well suited and established experimental method to study protein and water dynamics in the picosecond to nanosecond time- and Ångstrom length-scale. Using deuterium labelling either protein or water motions can be selected and brought into focus. Protein and cell water dynamics were separately studied in red blood cells. A consistent picture of cytoplasmic water and protein dynamics in whole cells is emerging from recent experimental results.
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Jasnin M, Stadler A, Tehei M, Zaccai G. Specific cellular water dynamics observed in vivo by neutron scattering and NMR. Phys Chem Chem Phys 2010; 12:10154-60. [DOI: 10.1039/c0cp01048k] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Slund I, Topgaard D. Determination of the self-diffusion coefficient of intracellular water using PGSE NMR with variable gradient pulse length. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2009; 201:250-254. [PMID: 19800273 DOI: 10.1016/j.jmr.2009.09.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Revised: 08/27/2009] [Accepted: 09/04/2009] [Indexed: 05/28/2023]
Abstract
A new pulsed-gradient spin-echo NMR protocol for assessing the local self-diffusion coefficient D(0) of water confined within living cells is proposed. Equations for the apparent mean-square displacement <Z(2)> as a function of the effective diffusion time t(d) and the duration of the displacement-encoding gradient pulses delta are derived. The standard method of estimating D(0)--reducing t(d) until the influence of collisions between the water molecules and the plasma membrane can be neglected--often fails because of the small size of typical cells. As demonstrated here, the decrease of the apparent <Z(2)> with increasing delta at constant t(d) can be utilized to measure D(0).
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Affiliation(s)
- Ingrid Slund
- Physical Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden
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Jasnin M. Atomic-scale dynamics inside living cells explored by neutron scattering. J R Soc Interface 2009; 6 Suppl 5:S611-7. [PMID: 19586955 DOI: 10.1098/rsif.2009.0144.focus] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Single-particle neutron spectroscopy has contributed important experimental data on molecular dynamics in biological systems. The technique provides information on atomic and molecular motions in macromolecules on the picosecond to the nanosecond time scale, which are essential to biological function. Here, we report on recent neutron measurements performed directly in living cells by using isotope labelling to explore the dynamics of specific cellular components. The paper proposes an integrated view of results on atomic-scale cell water dynamics, internal and global macromolecular motions and solvent isotope effect on macromolecular dynamics. The work established the specific usefulness of the neutron scattering technique to get insight into biologically relevant dynamical features, in particular through comparative measurements. The method developed can now be applied to look for dynamical signatures related to cell characteristics in many different cell types and organelles.
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Affiliation(s)
- Marion Jasnin
- Institut Laue-Langevin, 6 rue Jules Horowitz, BP 156, 38042 Grenoble Cedex 9, France.
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Hemoglobin senses body temperature. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2009; 38:589-600. [PMID: 19238378 DOI: 10.1007/s00249-009-0410-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 01/20/2009] [Accepted: 01/29/2009] [Indexed: 10/21/2022]
Abstract
UNLABELLED When aspirating human red blood cells (RBCs) into 1.3 mum pipettes (DeltaP = -2.3 kPa), a transition from blocking the pipette below a critical temperature T(c) = 36.3 +/- 0.3 degrees C to passing it above the T(c) occurred (micropipette passage transition). With a 1.1 mum pipette no passage was seen which enabled RBC volume measurements also above T(c). With increasing temperature RBCs lost volume significantly faster below than above a T(c) = 36.4 +/- 0.7 (volume transition). Colloid osmotic pressure (COP) measurements of RBCs in autologous plasma (25 degrees C < or = T < or = 39.5 degrees C) showed a T (c) at 37.1 +/- 0.2 degrees C above which the COP rapidly decreased (COP transition). In NMR T(1)-relaxation time measurements, the T(1) of RBCs in autologous plasma changed from a linear (r = 0.99) increment below T(c) = 37 +/- 1 degrees C at a rate of 0.023 s/K into zero slope above T(c) (RBC T(1) transition). IN CONCLUSION An amorphous hemoglobin-water gel formed in the spherical trail, the residual partial sphere of the aspirated RBC. At T(c), a sudden fluidization of the gel occurs. All changes mentioned above happen at a distinct T(c) close to body temperature. The T(c) is moved +0.8 degrees C to higher temperatures when a D(2)O buffer is used. We suggest a mechanism similar to a "glass transition" or a "colloidal phase transition". At T(c), the stabilizing Hb bound water molecules reach a threshold number enabling a partial Hb unfolding. Thus, Hb senses body temperature which must be inscribed in the primary structure of hemoglobin and possibly other proteins.
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