1
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Hishida M. Correlation between Hydration States and Self-assembly Structures of Phospholipid and Surfactant Studied by Terahertz Spectroscopy. J Oleo Sci 2024; 73:419-427. [PMID: 38556277 DOI: 10.5650/jos.ess23188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/02/2024] Open
Abstract
Phospholipids and surfactants form membranes and other self-assembled structures in water. However, it is not fully understood how the surrounding water (hydration water) is involved in their structure formation. In this paper, I summarize the results of our investigation of the long-range hydration state of phospholipids and surfactants at their surfaces by means of terahertz spectroscopy. By observing the collective rotational dynamics of water in the picosecond time scale, this technique allows us to observe not only the water directly bound to the solute, but also the weakly affected water outside of it. For example, PC phospholipids inhibit water dynamics over long distances, whereas PE phospholipids make water more mobile than bulk water. The causes of this difference in hydration and how it is involved in the structural formation of the membrane are reviewed.
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Affiliation(s)
- Mafumi Hishida
- Department of Chemistry, Faculty of Science, Tokyo University of Science
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2
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Hioki M, Nakagawa Y, Sato T. Presence of bicontinuous microemulsion-type domains and dielectrically inert interfacial water layers in lamellar gel-stabilized oil-in-water emulsions. J Colloid Interface Sci 2023; 651:829-840. [PMID: 37573729 DOI: 10.1016/j.jcis.2023.08.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 08/01/2023] [Accepted: 08/05/2023] [Indexed: 08/15/2023]
Abstract
HYPOTHESIS Lamellar gels are widely formulated in household and cosmetic products because of their eminent ability to improve long-term stability of thermodynamically unstable oil-in-water emulsions. However, despite long study, how and why membrane internal structure and membrane-membrane interactions are modified by the presence of polar and nonpolar oils remains elusive. EXPERIMENTS Using small- and wide-angle X-ray scattering, dielectric spectroscopy, and field-emission transmission electron microscope, we investigate intermembrane interactions and water-mediated microscopic interfacial properties in lamellar gels and lamellar gel-stabilized oil-in-water emulsions based on cetyltrimethylammonium chloride and 1-hexadecanol. FINDINGS Reducing membrane surface charge density enhances undulation fluctuation disorder, resulting in a crossover of dominant interactions from electrostatic double-layer repulsion to Helfrich interaction. Oil-emulsification induces similar structural impacts to the reduced 1-hexadecanol ratio, confirming preferential dissolution of higher-alcohol in oil phases. An emerging Teubner-Stray scattering component upon emulsification of nonpolar oil evidences that oil droplets and lamellar gels are indirectly connected via bicontinuous microemulsion-type domains. Dielectric spectra reveal strikingly small water permittivity in the lamellar gel and emulsion samples, which is quantitatively explained by a cumulative effect of a dielectrically inert interfacial thin water layer (<1nm) and a highly polarizable bulk-like water layer. This phenomenon appears to be intrinsic to diverse lamellar stack architectures.
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Affiliation(s)
- Marino Hioki
- Beauty Care Laboratory, Kracie Home Products, Ltd., 134 Goudo-cho, Hodogaya-Ku, Yokohama-City, Kanagawa 240-0005, Japan
| | - Yasuharu Nakagawa
- Beauty Care Laboratory, Kracie Home Products, Ltd., 134 Goudo-cho, Hodogaya-Ku, Yokohama-City, Kanagawa 240-0005, Japan.
| | - Takaaki Sato
- Department of Chemistry and Materials, Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan.
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3
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Chandra A, Kayal A, Das B, Chandra A. Dynamical Crossover of Interfacial Water upon Melting of a Lipid Bilayer: Influence of Different Parts of the Headgroups. J Phys Chem B 2023. [PMID: 38032152 DOI: 10.1021/acs.jpcb.3c04792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
All-atom molecular dynamics simulations of a 1,2-dimyristoyl-sn-glycero-3-phosphocholine bilayer in contact with liquid water were performed at different temperatures ranging from 285 to 320 K. We have investigated the heterogeneity and dynamical transitions in interfacial water as the lipid bilayer undergoes a melting transition. Results are obtained for water at the outer surface of the bilayer and for those buried more deeply in the lipid chains of the bilayer. It is found that lipid bilayer melting influences both the structure and dynamics of interfacial water. The number of interfacial water molecules shows a jump in the melting of the bilayer. The temperature dependence of the diffusivity and orientational relaxation of interfacial water molecules exhibits a dynamical crossover upon melting of the bilayer. The extent of dynamical crossover is found to be rather strong with significant changes in activation barriers for interfacial water around the carbonyl groups, which are deeply buried toward the lipid chains of the bilayer. The dynamical crossover gradually decreases as one moves further away from the outer surface, and it essentially vanishes for water in the region of 5-10 Å from the outer surface. It is found that the lipid melting-induced dynamical crossover of interfacial water is significant only for water that is in close proximity to the bilayer surface or deeply buried into it. The current results reveal that water molecules in different parts of the interface respond differently on melting of the bilayer. The current study also shows that the carbonyl-bound water molecules can play an important role in the phase transition of the bilayer as the temperature is raised through its melting point.
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Affiliation(s)
- Abhilash Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Uttar Pradesh 208016, India
| | - Abhijit Kayal
- Department of Chemistry, Indian Institute of Technology Kanpur, Uttar Pradesh 208016, India
| | - Banshi Das
- Department of Chemistry, Indian Institute of Technology Kanpur, Uttar Pradesh 208016, India
| | - Amalendu Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Uttar Pradesh 208016, India
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4
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Hishida M, Kaneko A, Yamamura Y, Saito K. Contrasting Changes in Strongly and Weakly Bound Hydration Water of a Protein upon Denaturation. J Phys Chem B 2023; 127:6296-6305. [PMID: 37417885 PMCID: PMC10364084 DOI: 10.1021/acs.jpcb.3c02970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/21/2023] [Indexed: 07/08/2023]
Abstract
Water is considered integral for the stabilization and function of proteins, which has recently attracted significant attention. However, the microscopic aspects of water ranging up to the second hydration shell, including strongly and weakly bound water at the sub-nanometer scale, are not yet well understood. Here, we combined terahertz spectroscopy, thermal measurements, and infrared spectroscopy to clarify how the strongly and weakly bound hydration water changes upon protein denaturation. With denaturation, that is, the exposure of hydrophobic groups in water and entanglement of hydrophilic groups, the number of strongly bound hydration water decreased, while the number of weakly bound hydration water increased. Even though the constraint of water due to hydrophobic hydration is weak, it extends to the second hydration shell as it is caused by the strengthening of hydrogen bonds between water molecules, which is likely the key microscopic mechanism for the destabilization of the native state due to hydration.
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Affiliation(s)
- Mafumi Hishida
- Department
of Chemistry, Faculty of Science, Tokyo
University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
| | - Ayumi Kaneko
- Department
of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
| | - Yasuhisa Yamamura
- Department
of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
| | - Kazuya Saito
- Department
of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
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5
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Rahman MK, Yamada T, Yamada NL, Hishida M, Higuchi Y, Seto H. Quasi-elastic neutron scattering reveals the relationship between the dynamical behavior of phospholipid headgroups and hydration water. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2023; 10:044701. [PMID: 37637480 PMCID: PMC10449016 DOI: 10.1063/4.0000184] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 08/04/2023] [Indexed: 08/29/2023]
Abstract
The dynamics of hydration water (HW) in 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine (DMPE) was investigated by means of quasi-elastic neutron scattering (QENS) and compared with those observed in 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). The headgroup dynamics of DMPE was investigated using a mixture of tail-deuterated DMPE and D2O, and the QENS profiles were interpreted as consisting of three modes. The fast mode comprised the rotation of hydrogen atoms in -NH3+ and -CH2- groups in the headgroup of DMPE, the medium-speed mode comprised fluctuations in the entire DMPE molecule, and the slow mode comprised fluctuations in the membrane. These interpretations were confirmed using molecular dynamics (MD) simulations. The HW dynamics analysis was performed on a tail-deuterated DMPE and H2O mixture. The QENS profiles were analyzed in terms of three modes: (1) a slow mode, identified as loosely bound HW in the DMPC membrane; (2) a medium-speed mode similar to free HW in the DMPC membrane; and (3) a fast mode, identified as rotational motion. The relaxation time for the fast mode was approximately six times shorter than that of rotational water in DMPC, consistent with the results of terahertz time-domain spectroscopy. The activation energy of medium-speed HW in DMPE differed from that of free HW in DMPC, suggesting the presence of different hydration states or hydrogen-bonded networks around the phosphocholine and phosphoethanolamine headgroups.
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Affiliation(s)
| | - Takeshi Yamada
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS), Tokai, Naka, Ibaraki 319-1106, Japan
| | | | - Mafumi Hishida
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
| | - Yuji Higuchi
- Research Institute for Information Technology, Kyushu University, 744 Motooka, Nishi-Ku, Fukuoka 819-0395, Japan
| | - Hideki Seto
- Authors to whom correspondence should be addressed: and
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6
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Nagao M, Seto H. Neutron scattering studies on dynamics of lipid membranes. BIOPHYSICS REVIEWS 2023; 4:021306. [PMID: 38504928 PMCID: PMC10903442 DOI: 10.1063/5.0144544] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 05/01/2023] [Indexed: 03/21/2024]
Abstract
Neutron scattering methods are powerful tools for the study of the structure and dynamics of lipid bilayers in length scales from sub Å to tens to hundreds nm and the time scales from sub ps to μs. These techniques also are nondestructive and, perhaps most importantly, require no additives to label samples. Because the neutron scattering intensities are very different for hydrogen- and deuterium-containing molecules, one can replace the hydrogen atoms in a molecule with deuterium to prepare on demand neutron scattering contrast without significantly altering the physical properties of the samples. Moreover, recent advances in neutron scattering techniques, membrane dynamics theories, analysis tools, and sample preparation technologies allow researchers to study various aspects of lipid bilayer dynamics. In this review, we focus on the dynamics of individual lipids and collective membrane dynamics as well as the dynamics of hydration water.
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Affiliation(s)
| | - Hideki Seto
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan
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7
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Malik S, Karmakar S, Debnath A. Relaxation time scales of interfacial water upon fluid to ripple to gel phase transitions of bilayers. J Chem Phys 2023; 158:114503. [PMID: 36948835 DOI: 10.1063/5.0138681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023] Open
Abstract
The slow relaxation of interface water (IW) across three primary phases of membranes is relevant to understand the influence of IW on membrane functions at supercooled conditions. To this objective, a total of ∼16.26μs all-atom molecular dynamics simulations of 1,2-dimyristoyl-sn-glycerol-3-phosphocholine lipid membranes are carried out. A supercooling-driven drastic slow-down in heterogeneity time scales of the IW is found at the fluid to the ripple to the gel phase transitions of the membranes. At both fluid-to-ripple-to-gel phase transitions, the IW undergoes two dynamic crossovers in Arrhenius behavior with the highest activation energy at the gel phase due to the highest number of hydrogen bonds. Interestingly, the Stokes-Einstein (SE) relation is conserved for the IW near all three phases of the membranes for the time scales derived from the diffusion exponents and the non-Gaussian parameters. However, the SE relation breaks for the time scale obtained from the self-intermediate scattering functions. The behavioral difference in different time scales is universal and found to be an intrinsic property of glass. The first dynamical transition in the α relaxation time of the IW is associated with an increase in the Gibbs energy of activation of hydrogen bond breaking with locally distorted tetrahedral structures, unlike the bulk water. Thus, our analyses unveil the nature of the relaxation time scales of the IW across membrane phase transitions in comparison with the bulk water. The results will be useful to understand the activities and survival of complex biomembranes under supercooled conditions in the future.
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Affiliation(s)
- Sheeba Malik
- Department of Chemistry, IIT Jodhpur, Jodhpur, Rajasthan, India
| | - Smarajit Karmakar
- Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad, India
| | - Ananya Debnath
- Department of Chemistry, IIT Jodhpur, Jodhpur, Rajasthan, India
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8
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Malik S, Karmakar S, Debnath A. Quantifying dynamical heterogeneity length scales of interface water across model membrane phase transitions. J Chem Phys 2023; 158:091103. [PMID: 36889951 DOI: 10.1063/5.0137727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
All-atom molecular dynamics simulations of 1,2-dimyristoyl-sn-glycero-3-phosphocholine lipid membranes reveal a drastic growth in the heterogeneity length scales of interface water (IW) across fluid to ripple to gel phase transitions. It acts as an alternate probe to capture the ripple size of the membrane and follows an activated dynamical scaling with the relaxation time scale solely within the gel phase. The results quantify the mostly unknown correlations between the spatiotemporal scales of the IW and membranes at various phases under physiological and supercooled conditions.
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Affiliation(s)
- Sheeba Malik
- Department of Chemistry, IIT Jodhpur, Jodhpur, Rajasthan, India
| | - Smarajit Karmakar
- Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad, India
| | - Ananya Debnath
- Department of Chemistry, IIT Jodhpur, Jodhpur, Rajasthan, India
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9
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Matsuo T, Cisse A, Plazanet M, Natali F, Koza MM, Ollivier J, Bicout DJ, Peters J. The dynamical Matryoshka model: 3. Diffusive nature of the atomic motions contained in a new dynamical model for deciphering local lipid dynamics. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183949. [PMID: 35508224 DOI: 10.1016/j.bbamem.2022.183949] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 04/06/2022] [Accepted: 04/25/2022] [Indexed: 11/17/2022]
Abstract
In accompanying papers [Bicout et al., BioRxiv https://doi.org/10.1101/2021.09.21.461198 (2021); Cissé et al., BioRxiv https://doi.org/10.1101/2022.03.30.486370 (2022)], a new model called Matryoshka model has been proposed to describe the geometry of atomic motions in phospholipid molecules in bilayers and multilamellar vesicles based on their quasielastic neutron scattering (QENS) spectra. Here, in order to characterize the relaxational aspects of this model, the energy widths of the QENS spectra of the samples were analyzed first in a model-free way. The spectra were decomposed into three Lorentzian functions, which are classified as slow, intermediate, and fast motions depending on their widths. The analysis provides the diffusion coefficients, residence times, and geometrical parameters for the three classes of motions. The results corroborate the parameter values such as the amplitudes and the mobile fractions of atomic motions obtained by the application of the Matryoshka model to the same samples. Since the current analysis was carried out independently of the development of the Matryoshka model, the present results enhance the validity of the model. The model will serve as a powerful tool to decipher the dynamics of lipid molecules not only in model systems, but also in more complex systems such as mixtures of different kinds of lipids or natural cell membranes.
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Affiliation(s)
- Tatsuhito Matsuo
- Univ. Grenoble Alpes, CNRS, LiPhy, F-38000 Grenoble, France; Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France; Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, 2-4 Shirakata, Tokai, Ibaraki 319-1106, Japan
| | - Aline Cisse
- Univ. Grenoble Alpes, CNRS, LiPhy, F-38000 Grenoble, France; Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France
| | - Marie Plazanet
- Univ. Grenoble Alpes, CNRS, LiPhy, F-38000 Grenoble, France
| | - Francesca Natali
- Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France; CNR-IOM, OGG, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France
| | - Michael Marek Koza
- Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France
| | - Jacques Ollivier
- Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France
| | - Dominique J Bicout
- Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France; Univ. Grenoble Alpes, CNRS, Grenoble INP, VetAgro Sup, TIMC, 38000 Grenoble, France
| | - Judith Peters
- Univ. Grenoble Alpes, CNRS, LiPhy, F-38000 Grenoble, France; Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France; Institut Universitaire de France, France.
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10
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Disalvo EA, Rosa AS, Cejas JP, Frias MDLA. Water as a Link between Membrane and Colloidal Theories for Cells. Molecules 2022; 27:4994. [PMID: 35956945 PMCID: PMC9370763 DOI: 10.3390/molecules27154994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/01/2022] [Accepted: 08/01/2022] [Indexed: 11/16/2022] Open
Abstract
This review is an attempt to incorporate water as a structural and thermodynamic component of biomembranes. With this purpose, the consideration of the membrane interphase as a bidimensional hydrated polar head group solution, coupled to the hydrocarbon region allows for the reconciliation of two theories on cells in dispute today: one considering the membrane as an essential part in terms of compartmentalization, and another in which lipid membranes are not necessary and cells can be treated as a colloidal system. The criterium followed is to describe the membrane state as an open, non-autonomous and responsive system using the approach of Thermodynamic of Irreversible Processes. The concept of an open/non-autonomous membrane system allows for the visualization of the interrelationship between metabolic events and membrane polymorphic changes. Therefore, the Association Induction Hypothesis (AIH) and lipid properties interplay should consider hydration in terms of free energy modulated by water activity and surface (lateral) pressure. Water in restricted regions at the lipid interphase has thermodynamic properties that explain the role of H-bonding networks in the propagation of events between membrane and cytoplasm that appears to be relevant in the context of crowded systems.
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Affiliation(s)
- E. Anibal Disalvo
- Applied Biophysics and Food Research Center (Centro de Investigaciones en Biofisica Aplicada y Alimentos, CIBAAL, Laboratory of Biointerphases and Biomimetic Systems, National University of Santiago del Estero and CONICET), RN 9-Km 1125, Santiago del Estero 4206, Argentina
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11
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Scollo F, Evci H, Amaro M, Jurkiewicz P, Sykora J, Hof M. What Does Time-Dependent Fluorescence Shift (TDFS) in Biomembranes (and Proteins) Report on? Front Chem 2021; 9:738350. [PMID: 34778202 PMCID: PMC8586494 DOI: 10.3389/fchem.2021.738350] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 09/21/2021] [Indexed: 11/17/2022] Open
Abstract
The organization of biomolecules and bioassemblies is highly governed by the nature and extent of their interactions with water. These interactions are of high intricacy and a broad range of methods based on various principles have been introduced to characterize them. As these methods view the hydration phenomena differently (e.g., in terms of time and length scales), a detailed insight in each particular technique is to promote the overall understanding of the stunning “hydration world.” In this prospective mini-review we therefore critically examine time-dependent fluorescence shift (TDFS)—an experimental method with a high potential for studying the hydration in the biological systems. We demonstrate that TDFS is very useful especially for phospholipid bilayers for mapping the interfacial region formed by the hydrated lipid headgroups. TDFS, when properly applied, reports on the degree of hydration and mobility of the hydrated phospholipid segments in the close vicinity of the fluorophore embedded in the bilayer. Here, the interpretation of the recorded TDFS parameters are thoroughly discussed, also in the context of the findings obtained by other experimental techniques addressing the hydration phenomena (e.g., molecular dynamics simulations, NMR spectroscopy, scattering techniques, etc.). The differences in the interpretations of TDFS outputs between phospholipid biomembranes and proteins are also addressed. Additionally, prerequisites for the successful TDFS application are presented (i.e., the proper choice of fluorescence dye for TDFS studies, and TDFS instrumentation). Finally, the effects of ions and oxidized phospholipids on the bilayer organization and headgroup packing viewed from TDFS perspective are presented as application examples.
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Affiliation(s)
- Federica Scollo
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Hüseyin Evci
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Mariana Amaro
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Piotr Jurkiewicz
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Jan Sykora
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
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12
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Atamas N, Gavryushenko D, Yablochkova K, Lazarenko M, Taranyik G. Temperature and temporal heterogeneities of water dynamics in the physiological temperature range. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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13
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Ilangumaran Ponmalar I, Sarangi NK, Basu JK, Ayappa KG. Pore Forming Protein Induced Biomembrane Reorganization and Dynamics: A Focused Review. Front Mol Biosci 2021; 8:737561. [PMID: 34568431 PMCID: PMC8459938 DOI: 10.3389/fmolb.2021.737561] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 07/30/2021] [Indexed: 11/13/2022] Open
Abstract
Pore forming proteins are a broad class of pathogenic proteins secreted by organisms as virulence factors due to their ability to form pores on the target cell membrane. Bacterial pore forming toxins (PFTs) belong to a subclass of pore forming proteins widely implicated in bacterial infections. Although the action of PFTs on target cells have been widely investigated, the underlying membrane response of lipids during membrane binding and pore formation has received less attention. With the advent of superresolution microscopy as well as the ability to carry out molecular dynamics (MD) simulations of the large protein membrane assemblies, novel microscopic insights on the pore forming mechanism have emerged over the last decade. In this review, we focus primarily on results collated in our laboratory which probe dynamic lipid reorganization induced in the plasma membrane during various stages of pore formation by two archetypal bacterial PFTs, cytolysin A (ClyA), an α-toxin and listeriolysin O (LLO), a β-toxin. The extent of lipid perturbation is dependent on both the secondary structure of the membrane inserted motifs of pore complex as well as the topological variations of the pore complex. Using confocal and superresolution stimulated emission depletion (STED) fluorescence correlation spectroscopy (FCS) and MD simulations, lipid diffusion, cholesterol reorganization and deviations from Brownian diffusion are correlated with the oligomeric state of the membrane bound protein as well as the underlying membrane composition. Deviations from free diffusion are typically observed at length scales below ∼130 nm to reveal the presence of local dynamical heterogeneities that emerge at the nanoscale-driven in part by preferential protein binding to cholesterol and domains present in the lipid membrane. Interrogating the lipid dynamics at the nanoscale allows us further differentiate between binding and pore formation of β- and α-PFTs to specific domains in the membrane. The molecular insights gained from the intricate coupling that occurs between proteins and membrane lipids and receptors during pore formation are expected to improve our understanding of the virulent action of PFTs.
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Affiliation(s)
| | - Nirod K. Sarangi
- School of Chemical Science, Dublin City University, Dublin, Ireland
| | - Jaydeep K. Basu
- Department of Physics, Indian Institute of Science, Bangalore, India
| | - K. Ganapathy Ayappa
- Center for BioSystems Science and Engineering, Indian Institute of Science, Bangalore, India
- Department of Chemical Engineering, Indian Institute of Science, Bengaluru, India
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14
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Meineke J, Weik M, Zaccai G, Fragneto G. Behavior of Hydrated Lipid Bilayers at Cryogenic Temperatures. Front Chem 2020; 8:455. [PMID: 32626684 PMCID: PMC7314993 DOI: 10.3389/fchem.2020.00455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 05/01/2020] [Indexed: 12/02/2022] Open
Abstract
Neutron diffraction was used to study the behavior of water present in phospholipid multilamellar stacks from 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC) at cryogenic temperatures. Evidence was found for the existence of a highly viscous phase of water that exists between 180 and 220 K based on the observation that water can leave the intermembrane space at these low temperatures. Similar measurements are described in the literature for purple membrane (PM) samples. From a comparison with results from this natural membrane by using the same flash-cooling protocol, it is found that in the case of pure lipid samples, less water is trapped and the water flows out at lower temperatures. This suggests that the water is less hindered in its movements than in the PM case. It is shown that at least the Lβ′-phase of DMPC can be trapped likely by flash cooling; upon heating to about 260 K, it transforms to another phase that was not fully characterized.
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Affiliation(s)
- Jakob Meineke
- University of Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, Grenoble, France
| | - Martin Weik
- University of Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, Grenoble, France
| | - Giuseppe Zaccai
- University of Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, Grenoble, France.,Institut Laue-Langevin, Grenoble, France
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15
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The crucial role of water in the formation of the physiological temperature range for warm-blooded organisms. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112818] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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16
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Yamada T, Seto H. Quasi-Elastic Neutron Scattering Studies on Hydration Water in Phospholipid Membranes. Front Chem 2020; 8:8. [PMID: 32039163 PMCID: PMC6993101 DOI: 10.3389/fchem.2020.00008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 01/07/2020] [Indexed: 11/20/2022] Open
Abstract
The dynamic behavior of hydration water in phospholipid membranes has been investigated to understand the relationship between water and biological molecules using various experimental techniques. Quasi-elastic neutron scattering (QENS) is an effective method for this purpose because the dynamic behaviors of both water and lipid molecules could be identified by using selective deuteration. In addition, the measurable ranges from the 10−12 to 10−9 s time scale and the 10−11 to 10−8 m length scale are suitable to investigate the slowing down of water molecules due to their interaction with lipid membranes. In this mini-review, QENS experiments on the dynamic behavior of hydration water molecules in neighboring phospholipid membranes are summarized.
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Affiliation(s)
- Takeshi Yamada
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society, Tokai, Japan
| | - Hideki Seto
- Institute of Materials Structure Science/J-PARC Center, High Energy Accelerator Research Organization, Tsukuba, Japan
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17
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Heterogeneity in structure and dynamics of water near bilayers using TIP3P and TIP4P/2005 water models. Chem Phys 2019. [DOI: 10.1016/j.chemphys.2019.110396] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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18
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Salvati Manni L, Assenza S, Duss M, Vallooran JJ, Juranyi F, Jurt S, Zerbe O, Landau EM, Mezzenga R. Soft biomimetic nanoconfinement promotes amorphous water over ice. NATURE NANOTECHNOLOGY 2019; 14:609-615. [PMID: 30962546 DOI: 10.1038/s41565-019-0415-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 02/26/2019] [Indexed: 06/09/2023]
Abstract
Water is a ubiquitous liquid with unique physicochemical properties, whose nature has shaped our planet and life as we know it. Water in restricted geometries has different properties than in bulk. Confinement can prevent low-temperature crystallization of the molecules into a hexagonal structure and thus create a state of amorphous water. To understand the survival of life at subzero temperatures, it is essential to elucidate this behaviour in the presence of nanoconfining lipidic membranes. Here we introduce a family of synthetic lipids with designed cyclopropyl modifications in the hydrophobic chains that exhibit unique liquid-crystalline behaviour at low temperature, which enables the maintenance of amorphous water down to ~10 K due to nanoconfinement. The combination of experiments and molecular dynamics simulations unveils a complex lipid-water phase diagram in which bicontinuous cubic and lamellar liquid crystalline phases that contain subzero liquid, glassy or ice water emerge as a competition between the two components, each pushing towards its thermodynamically favoured state.
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Affiliation(s)
- Livia Salvati Manni
- Department of Chemistry, University of Zürich, Zürich, Switzerland
- Department of Health Sciences & Technology, ETH Zürich, Zürich, Switzerland
| | - Salvatore Assenza
- Department of Health Sciences & Technology, ETH Zürich, Zürich, Switzerland
| | - Michael Duss
- Department of Chemistry, University of Zürich, Zürich, Switzerland
| | - Jijo J Vallooran
- Department of Chemistry, University of Zürich, Zürich, Switzerland
- Department of Health Sciences & Technology, ETH Zürich, Zürich, Switzerland
| | - Fanni Juranyi
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, Villigen, Switzerland
| | - Simon Jurt
- Department of Chemistry, University of Zürich, Zürich, Switzerland
| | - Oliver Zerbe
- Department of Chemistry, University of Zürich, Zürich, Switzerland
| | - Ehud M Landau
- Department of Chemistry, University of Zürich, Zürich, Switzerland.
| | - Raffaele Mezzenga
- Department of Health Sciences & Technology, ETH Zürich, Zürich, Switzerland.
- Department of Materials, ETH Zürich, Zürich, Switzerland.
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19
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Singh P, Sharma VK, Singha S, García Sakai V, Mukhopadhyay R, Das R, Pal SK. Unraveling the Role of Monoolein in Fluidity and Dynamical Response of a Mixed Cationic Lipid Bilayer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4682-4692. [PMID: 30807692 DOI: 10.1021/acs.langmuir.9b00043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The maintenance of cell membrane fluidity is of critical importance for various cellular functions. At lower temperatures when membrane fluidity decreases, plants and cyanobacteria react by introducing unsaturation in the lipids, so that the membranes return to a more fluidic state. To probe how introduction of unsaturation leads to reduced membrane fluidity, a model cationic lipid dioctadecyldimethylammonium bromide (DODAB) has been chosen, and the effects of an unsaturated lipid monoolein (MO) on the structural dynamics and phase behavior of DODAB have been monitored by quasielastic neutron scattering and time-resolved fluorescence measurements. In the coagel phase, fluidity of the lipid bilayer increases significantly in the presence of MO relative to pure DODAB vesicles and becomes manifest in significantly enhanced dynamics of the constituent lipids along with faster hydration and orientational relaxation dynamics of a fluorophore. On the contrary, MO restricts both lateral and internal motions of the lipid molecules in the fluid phase (>330 K), which is consistent with relatively slow hydration and orientational relaxation dynamics of the fluorophore embedded in the mixed lipid bilayer. The present study illustrates how incorporation of an unsaturated lipid at lower temperatures (below the phase transition) assists the model lipid (DODAB) in regulating fluidity via enhancement of dynamics of the constituent lipids.
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Affiliation(s)
- Priya Singh
- Department of Chemical, Biological & Macromolecular Sciences , S. N. Bose National Centre for Basic Sciences , Block JD, Sector III , Salt Lake, Kolkata 700106 , India
| | | | - Subhankar Singha
- Department of Chemistry , Pohang University of Science and Technology (POSTECH) , 77 Cheongam-Ro , Nam-Gu, Pohang , Gyungbuk 37673 , Republic of Korea
| | - Victoria García Sakai
- ISIS Pulsed Neutron and Muon Facility, Rutherford Appleton Laboratory , Science and Technology Facilities Council , Didcot OX11 0DE , U.K
| | | | - Ranjan Das
- Department of Chemistry , West Bengal State University , Barasat, Kolkata 700126 , India
| | - Samir Kumar Pal
- Department of Chemical, Biological & Macromolecular Sciences , S. N. Bose National Centre for Basic Sciences , Block JD, Sector III , Salt Lake, Kolkata 700106 , India
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20
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Jackson GL, Mantha S, Kim SA, Diallo SO, Herwig KW, Yethiraj A, Mahanthappa MK. Ion-Specific Confined Water Dynamics in Convex Nanopores of Gemini Surfactant Lyotropic Liquid Crystals. J Phys Chem B 2018; 122:10031-10043. [PMID: 30251848 DOI: 10.1021/acs.jpcb.8b05942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The impact of pore geometry and functionality on the dynamics of water nanoconfined in porous media are the subject of some debate. We report the synthesis and small-angle X-ray scattering (SAXS) characterization of a series of perdeuterated gemini surfactant lyotropic liquid crystals (LLCs), in which convex, water-filled nanopores of well-defined dimensions are lined with carboxylate functionalities. Quasielastic neutron scattering (QENS) measurements of the translational water dynamics in these dicarboxylate LLC nanopores as functions of the surfactant hydration state and the charge compensating counterion (Na+, K+, NMe4+) reveal that the measured dynamics depend primarily on surfactant hydration, with an unexpected counterion dependence that varies with hydration number. We rationalize these trends in terms of a balance between counterion-water attractions and the nanopore volume excluded by the counterions. On the basis of electron density maps derived from SAXS analyses of these LLCs, we directly show that the volume excluded by the counterions depends on both their size and spatial distribution in the water-filled channels. The translational water dynamics in the convex pores of these LLCs are also slower than those reported in the concave pores of AOT reverse micelles, implying that water dynamics also depend on the nanopore curvature.
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Affiliation(s)
- Grayson L Jackson
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Sriteja Mantha
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Sung A Kim
- Department of Chemical Engineering & Materials Science , University of Minnesota , 421 Washington Avenue, S.E. , Minneapolis , Minnesota 55455 , United States
| | | | | | - Arun Yethiraj
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Mahesh K Mahanthappa
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , Wisconsin 53706 , United States.,Department of Chemical Engineering & Materials Science , University of Minnesota , 421 Washington Avenue, S.E. , Minneapolis , Minnesota 55455 , United States
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21
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Nanda H, García Sakai V, Khodadadi S, Tyagi MS, Schwalbach EJ, Curtis JE. Relaxation dynamics of saturated and unsaturated oriented lipid bilayers. SOFT MATTER 2018; 14:6119-6127. [PMID: 29998268 PMCID: PMC6262841 DOI: 10.1039/c7sm01720k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We present experimental measurements and analysis of the dynamics and the phase behaviour of saturated DMPC and unsaturated DOPC oriented multi-lamellar bilayers. Elastic and inelastic neutron scattering were used to directly probe the dynamical processes of these membrane systems on time and length scales relevant to the internal and localized motion of lipid monomers. Mobility in this regime can be informative in elucidating the local interactions responsible for material properties of these fluid lipid systems. DMPC and DOPC are structurally similar in terms of their membrane hydrophobic thickness; however, they exhibit different mechanical properties in terms of both elastic compressibility and bending moduli. The analyses suggest that the constraint imposed by the double bonds in DOPC acyl chains restricts atomic motion in both liquid and gel phases compared to DMPC. We discuss applications of molecular dynamics to further elucidate the atomic details of the dynamical processes. Such an understanding may suggest how membrane properties can be tuned using a variety of different lipid species.
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Affiliation(s)
- Hirsh Nanda
- NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 6102, Gaithersburg, MD 20899, USA.
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22
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Srivastava A, Debnath A. Hydration dynamics of a lipid membrane: Hydrogen bond networks and lipid-lipid associations. J Chem Phys 2018. [DOI: 10.1063/1.5011803] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Affiliation(s)
- Abhinav Srivastava
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwad, Rajasthan, India
| | - Ananya Debnath
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwad, Rajasthan, India
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23
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Yamada T, Takahashi N, Tominaga T, Takata SI, Seto H. Dynamical Behavior of Hydration Water Molecules between Phospholipid Membranes. J Phys Chem B 2017; 121:8322-8329. [PMID: 28787155 DOI: 10.1021/acs.jpcb.7b01276] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The dynamical behavior of hydration water sandwiched between 1,2-dimyristyl-sn-glycero-3-phosphocholine (DMPC) bilayers was investigated by quasi-elastic neutron scattering (QENS) in the range between 275 and 316 K, where the main transition temperature of DMPC is interposed. The results revealed that the hydration water could be categorized into three types of water: (1) free water, whose dynamical behavior is slightly different from that of bulk water; (2) loosely bound water, whose dynamical behavior is 1 order of magnitude slower than that of the free water; and (3) tightly bound water, whose dynamical behavior is comparable with that of DMPC molecules. The number of loosely bound and tightly bound water molecules per DMPC molecule monotonically decreased and increased with decreasing temperature, respectively, and the sum of these water molecules remained constant. The number of free water molecules per DMPC molecule was constant in the measured temperature range.
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Affiliation(s)
- Takeshi Yamada
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS) , 162-1 Shirakata, Tokai, Naka, Ibaraki, Japan 319-1106
| | - Nobuaki Takahashi
- Institute for Chemical Research, Kyoto University Gokasho , Uji, Kyoto, Japan 611-0011
| | - Taiki Tominaga
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS) , 162-1 Shirakata, Tokai, Naka, Ibaraki, Japan 319-1106
| | - Shin-Ichi Takata
- J-PARC Center, Japan Atomic Energy Agency , 2-4 Shirakata, Tokai, Japan 319-1195
| | - Hideki Seto
- J-PARC Center, High Energy Accelerator Research Organization , 203-1 Shirakata, Tokai, Ibaraki, Japan 319-1106
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24
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Miskowiec A, Buck ZN, Hansen FY, Kaiser H, Taub H, Tyagi M, Diallo SO, Mamontov E, Herwig KW. On the structure and dynamics of water associated with single-supported zwitterionic and anionic membranes. J Chem Phys 2017; 146:125102. [DOI: 10.1063/1.4978677] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- A. Miskowiec
- Department of Physics and Astronomy and University of Missouri Research Reactor, University of Missouri, Columbia, Missouri 65211, USA
| | - Z. N. Buck
- Department of Physics and Astronomy and University of Missouri Research Reactor, University of Missouri, Columbia, Missouri 65211, USA
| | - F. Y. Hansen
- Department of Chemistry, Technical University of Denmark, IK 207 DTU, DK-2800 Lyngby, Denmark
| | - H. Kaiser
- Department of Physics and Astronomy and University of Missouri Research Reactor, University of Missouri, Columbia, Missouri 65211, USA
| | - H. Taub
- Department of Physics and Astronomy and University of Missouri Research Reactor, University of Missouri, Columbia, Missouri 65211, USA
| | - M. Tyagi
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102, USA
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, USA
| | - S. O. Diallo
- Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - E. Mamontov
- Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - K. W. Herwig
- Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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25
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D'Angelo G, Conti Nibali V, Crupi C, Rifici S, Wanderlingh U, Paciaroni A, Sacchetti F, Branca C. Probing Intermolecular Interactions in Phospholipid Bilayers by Far-Infrared Spectroscopy. J Phys Chem B 2017; 121:1204-1210. [PMID: 28118017 DOI: 10.1021/acs.jpcb.6b10323] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fast thermal fluctuations and low frequency phonon modes are thought to play a part in the dynamic mechanisms of many important biological functions in cell membranes. Here we report a detailed far-infrared study of the molecular subpicosecond motions of phospholipid bilayers at various hydrations. We show that these systems sustain several low frequency collective modes and deduce that they arise from vibrations of different lipids interacting through intermolecular van der Waals forces. Furthermore, we observe that the low frequency vibrations of lipid membrane have strong similarities with the subpicosecond motions of liquid water and suggest that resonance mechanisms are an important element to the dynamics coupling between membranes and their hydration water.
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Affiliation(s)
- Giovanna D'Angelo
- Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98122 Messina, Italy
| | - Valeria Conti Nibali
- Institute for Physical Chemistry II, Ruhr-University Bochum , 44801 Bochum, Germany
| | - Cristina Crupi
- Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98122 Messina, Italy
| | - Simona Rifici
- Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98122 Messina, Italy
| | - Ulderico Wanderlingh
- Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98122 Messina, Italy
| | - Alessandro Paciaroni
- Dipartimento di Fisica, Università degli Studi di Perugia , 06123 Perugia, Italy
| | - Francesco Sacchetti
- Dipartimento di Fisica, Università degli Studi di Perugia , 06123 Perugia, Italy
| | - Caterina Branca
- Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98122 Messina, Italy
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26
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Inelastic and quasi-elastic neutron scattering spectrometers in J-PARC. Biochim Biophys Acta Gen Subj 2016; 1861:3651-3660. [PMID: 27156489 DOI: 10.1016/j.bbagen.2016.04.025] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 04/21/2016] [Accepted: 04/22/2016] [Indexed: 11/20/2022]
Abstract
J-PARC, Japan Proton Accelerator Research Complex provides short pulse proton beam at a repetition rate 25Hz and the maximum power is expected to be 1MW. Materials and Life Science Experimental Facility (MLF) has 23 neutron beam ports and 21 instruments have already been operated or under construction/commissioning. There are 6 inelastic/quasi-elastic neutron scattering spectrometers and the complementary use of these spectrometers will open new insight for life science. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo.
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27
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Rønnest AK, Peters GH, Hansen FY, Taub H, Miskowiec A. Structure and dynamics of water and lipid molecules in charged anionic DMPG lipid bilayer membranes. J Chem Phys 2016; 144:144904. [DOI: 10.1063/1.4945278] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- A. K. Rønnest
- Department of Chemistry, Technical University of Denmark, IK 207 DTU, DK-2800 Lyngby, Denmark
| | - G. H. Peters
- Department of Chemistry, Technical University of Denmark, IK 207 DTU, DK-2800 Lyngby, Denmark
| | - F. Y. Hansen
- Department of Chemistry, Technical University of Denmark, IK 207 DTU, DK-2800 Lyngby, Denmark
| | - H. Taub
- Department of Physics and Astronomy and the University of Missouri Research Reactor,University of Missouri, Columbia, Missouri 65211, USA
| | - A. Miskowiec
- Department of Physics and Astronomy and the University of Missouri Research Reactor,University of Missouri, Columbia, Missouri 65211, USA
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28
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Marquardt D, Heberle FA, Nickels JD, Pabst G, Katsaras J. On scattered waves and lipid domains: detecting membrane rafts with X-rays and neutrons. SOFT MATTER 2015; 11:9055-72. [PMID: 26428538 PMCID: PMC4719199 DOI: 10.1039/c5sm01807b] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/21/2015] [Indexed: 05/28/2023]
Abstract
In order to understand the biological role of lipids in cell membranes, it is necessary to determine the mesoscopic structure of well-defined model membrane systems. Neutron and X-ray scattering are non-invasive, probe-free techniques that have been used extensively in such systems to probe length scales ranging from angstroms to microns, and dynamics occurring over picosecond to millisecond time scales. Recent developments in the area of phase separated lipid systems mimicking membrane rafts will be presented, and the underlying concepts of the different scattering techniques used to study them will be discussed in detail.
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Affiliation(s)
- Drew Marquardt
- University of Graz, Institute of Molecular Biosciences, Biophysics Division, NAWI Graz, Humboldtstr. 50/III, Graz, Austria. and BioTechMed-Graz, Graz, Austria
| | - Frederick A Heberle
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. and Joint Institute for Neutron Sciences, Oak Ridge, Tennessee 37831, USA
| | - Jonathan D Nickels
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. and Joint Institute for Neutron Sciences, Oak Ridge, Tennessee 37831, USA
| | - Georg Pabst
- University of Graz, Institute of Molecular Biosciences, Biophysics Division, NAWI Graz, Humboldtstr. 50/III, Graz, Austria. and BioTechMed-Graz, Graz, Austria
| | - John Katsaras
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. and Joint Institute for Neutron Sciences, Oak Ridge, Tennessee 37831, USA
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29
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Abstract
Water is crucial to the structure and function of biological membranes. In fact, the membrane's basic structural unit, i.e. the lipid bilayer, is self-assembled and stabilized by the so-called hydrophobic effect, whereby lipid molecules unable to hydrogen bond with water aggregate in order to prevent their hydrophobic portions from being exposed to water. However, this is just the beginning of the lipid-bilayer-water relationship. This mutual interaction defines vesicle stability in solution, controls small molecule permeation, and defines the spacing between lamella in multi-lamellar systems, to name a few examples. This chapter will describe the structural and dynamical properties central to these, and other water- lipid bilayer interactions.
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Affiliation(s)
- Jonathan D Nickels
- Joint Institute for Neutron Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
| | - John Katsaras
- Biology & Soft Matter and Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
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30
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Yamamoto N, Andachi T, Tamura A, Tominaga K. Temperature and Hydration Dependence of Low-Frequency Spectra of Lipid Bilayers Studied by Terahertz Time-Domain Spectroscopy. J Phys Chem B 2014; 119:9359-68. [PMID: 25474750 DOI: 10.1021/jp5099766] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have studied temperature and hydration dependent low-frequency spectra of lipid bilayers of 1,2-dimyristoyl-sn-glycero-3-phosphoryl-3'-rac-glycerol (DMPG) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) by terahertz time-domain spectroscopy (THz-TDS). We measured X-ray diffraction patterns and mid-infrared spectra of these lipid bilayers and found that the lipid bilayers have two different types of phases, i.e., the gel phase and the crystalline phase, depending on the preparation methods of the samples. In both phases, a few distinct bands were observed in the THz region. For DMPG, the peak wavenumbers of the absorption bands did not change upon hydration, while the bandwidth in the crystalline phase was smaller than that in the gel phase. We performed spectral analyses for the complex dielectric spectra for DMPG and DMPC with a model function, mainly to determine the peak wavenumbers of the absorption bands. In contrast to the case of the DMPG bilayers, the peak wavenumber of the absorption band of the DMPC bilayer shifts upon hydration. In the hydrated DMPC bilayer, it was suggested fast reorienting water molecules exist with a relaxation time of sub-picoseconds. It is suggested that the THz absorption patterns reflect the lipid packing pattern in the bilayers. The temperature dependence of the absorption band was analyzed by an empirical equation, and the anharmonicity of the vibrational potential of the low-frequency mode was quantitatively evaluated.
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Affiliation(s)
- Naoki Yamamoto
- †Molecular Photoscience Research Center and ‡Graduate School of Science, Kobe University, Rokkodai-cho 1-1, Nada, Kobe 657-8501, Japan
| | - Tomoyo Andachi
- †Molecular Photoscience Research Center and ‡Graduate School of Science, Kobe University, Rokkodai-cho 1-1, Nada, Kobe 657-8501, Japan
| | - Atsuo Tamura
- †Molecular Photoscience Research Center and ‡Graduate School of Science, Kobe University, Rokkodai-cho 1-1, Nada, Kobe 657-8501, Japan
| | - Keisuke Tominaga
- †Molecular Photoscience Research Center and ‡Graduate School of Science, Kobe University, Rokkodai-cho 1-1, Nada, Kobe 657-8501, Japan
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31
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Knoll W, Peters J, Kursula P, Gerelli Y, Ollivier J, Demé B, Telling M, Kemner E, Natali F. Structural and dynamical properties of reconstituted myelin sheaths in the presence of myelin proteins MBP and P2 studied by neutron scattering. SOFT MATTER 2014; 10:519-529. [PMID: 24651633 DOI: 10.1039/c3sm51393a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The myelin sheath is a tightly packed, multilayered membrane structure wrapped around selected nerve axons in the central and the peripheral nervous system. Because of its electrical insulation of the axons, which allows fast, saltatory nerve impulse conduction, myelin is crucial for the proper functioning of the vertebrate nervous system. A subset of myelin-specific proteins is well-defined, but their influence on membrane dynamics, i.e. myelin stability, has not yet been explored in detail. We investigated the structure and the dynamics of reconstituted myelin membranes on a pico- to nanosecond timescale, influenced by myelin basic protein (MBP) and myelin protein 2 (P2), using neutron diffraction and quasi-elastic neutron scattering. A model for the scattering function describing molecular lipid motions is suggested. Although dynamical properties are not affected significantly by MBP and P2 proteins, they act in a highly synergistic manner influencing the membrane structure.
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Affiliation(s)
- Wiebke Knoll
- University Joseph Fourier UFR PhITEM, Grenoble, France
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32
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von Hansen Y, Gekle S, Netz RR. Anomalous anisotropic diffusion dynamics of hydration water at lipid membranes. PHYSICAL REVIEW LETTERS 2013; 111:118103. [PMID: 24074121 DOI: 10.1103/physrevlett.111.118103] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Indexed: 06/02/2023]
Abstract
The diffusional water dynamics in the hydration layer of a dipalmitoylphosphatidylcholine bilayer is studied using molecular dynamics simulations. By mapping the perpendicular water motion on the ordinary diffusion equation, we disentangle free energetic and friction effects and show that perpendicular diffusion is strongly reduced. The lateral water motion exhibits anomalous diffusion up to several nanoseconds and is characterized by even further decreased diffusion coefficients, which by comparison with coarse-grained simulations are explained by the transient corrugated effective free energy landscape imposed by the lipids. This is in contrast to homogenous surfaces, where boundary hydrodynamic theory quantitatively predicts the anisotropy of water diffusion.
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Affiliation(s)
- Yann von Hansen
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany and Physics Department, Technische Universität München, 85748 Garching, Germany
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33
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Hansen FY, Peters GH, Taub H, Miskowiec A. Diffusion of water and selected atoms in DMPC lipid bilayer membranes. J Chem Phys 2013. [PMID: 23206034 DOI: 10.1063/1.4767568] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Molecular dynamics simulations have been used to determine the diffusion of water molecules as a function of their position in a fully hydrated freestanding 1,2-dimyristoyl-sn-glycero-3-phosphorylcholine (DMPC) bilayer membrane at 303 K and 1 atm. The diffusion rate of water in a ∼10 Å thick layer just outside the membrane surface is reduced on average by a factor of ∼2 relative to bulk. For water molecules penetrating deeper into the membrane, there is an increasing reduction in the average diffusion rate with up to one order of magnitude decrease for those deepest in the membrane. A comparison with the diffusion rate of selected atoms in the lipid molecules shows that ∼6 water molecules per lipid molecule move on the same time scale as the lipids and may therefore be considered to be tightly bound to them. The quasielastic neutron scattering functions for water and selected atoms in the lipid molecule have been simulated and compared to observed quasielastic neutron scattering spectra from single-supported bilayer DMPC membranes.
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Affiliation(s)
- F Y Hansen
- Department of Chemistry, Technical University of Denmark, IK 207 DTU, DK-2800 Lyngby, Denmark.
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Choi DH, Son H, Jung S, Park J, Park WY, Kwon OS, Park GS. Dielectric relaxation change of water upon phase transition of a lipid bilayer probed by terahertz time domain spectroscopy. J Chem Phys 2013; 137:175101. [PMID: 23145747 DOI: 10.1063/1.4764304] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We investigate the influence of the 1, 2-ditetradecanoyl-sn-glycero-3-phosphocholine lipid bilayer phases on the water reorientation dynamics with terahertz time domain spectroscopy. The phase of the lipids was controlled by the temperature in the range of 14-35 °C. During the gel-to-fluid phase transition, the hydration water ratio drastically changed from 0.3 to 0.6. The absorption coefficient of the hydration water increased with the temperature in the gel phase and then decreased in the fluid phase. The dielectric relaxation time of the lipid solution decreased initially but then increased after the phase transition. This indicates that the hydration water reorientation dynamics are restricted by lipids and that this phenomenon is pronounced in a biologically relevant fluid phase.
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Affiliation(s)
- Da-Hye Choi
- Center for THz-Bio Application Systems, Department of Physics and Astronomy, Seoul National University, Seoul 151-747, South Korea
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Debnath A, Ayappa KG, Maiti PK. Simulation of influence of bilayer melting on dynamics and thermodynamics of interfacial water. PHYSICAL REVIEW LETTERS 2013; 110:018303. [PMID: 23383847 DOI: 10.1103/physrevlett.110.018303] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 09/23/2012] [Indexed: 06/01/2023]
Abstract
We investigate the effect of bilayer melting transition on thermodynamics and dynamics of interfacial water using molecular dynamics simulation with the two-phase thermodynamic model. We show that the diffusivity of interface water depicts a dynamic crossover at the chain melting transition following an Arrhenius behavior until the transition temperature. The corresponding change in the diffusion coefficient from the bulk to the interface water is comparable with experimental observations found recently for water near 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) vesicles [Phys. Chem. Chem. Phys. 13, 7732 (2011)]. The entropy and potential energy of interfacial water show distinct changes at the bilayer melting transition, indicating a strong correlation in the thermodynamic state of water and the accompanying first-order phase transition of the bilayer membrane.
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Affiliation(s)
- Ananya Debnath
- Department of Chemical Engineering, Indian Institute of Science, Bangalore 560012, India.
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Poger D, Mark AE. Lipid Bilayers: The Effect of Force Field on Ordering and Dynamics. J Chem Theory Comput 2012; 8:4807-17. [PMID: 26605633 DOI: 10.1021/ct300675z] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The sensitivity of the structure and dynamics of a fully hydrated pure bilayer of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in molecular dynamics simulations to changes in force-field and simulation parameters has been assessed. Three related force fields (the Gromos 54A7 force field, a Gromos 53A6-derived parameter set and a variant of the Berger parameters) in combination with either particle-mesh Ewald (PME) or a reaction field (RF) were compared. Structural properties such as the area per lipid, carbon-deuterium order parameters, electron density profile and bilayer thicknesses, are reproduced by all the parameter sets within the uncertainty of the available experimental data. However, there are clear differences in the ordering of the glycerol backbone and choline headgroup, and the orientation of the headgroup dipole. In some cases, the degree of ordering was reminiscent of a liquid-ordered phase. It is also shown that, although the lateral diffusion of the lipids in the plane of the bilayer is often used to validate lipid force fields, because of the uncertainty in the experimental measurements and the fact that the lateral diffusion is dependent on the choice of the simulation conditions, it should not be employed as a measure of quality. Finally, the simulations show that the effect of small changes in force-field parameters on the structure and dynamics of a bilayer is more significant than the treatment of the long-range electrostatic interactions using RF or PME. Overall, the Gromos 54A7 best reproduced the range of experimental data examined.
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Affiliation(s)
- David Poger
- The University of Queensland, School of Chemistry and Molecular Biosciences, Brisbane QLD 4072, Australia
| | - Alan E Mark
- The University of Queensland, School of Chemistry and Molecular Biosciences, Brisbane QLD 4072, Australia.,The University of Queensland, Institute for Molecular Bioscience, Brisbane QLD 4072, Australia
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37
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Hishida M, Tanaka K. Transition of the hydration state of a surfactant accompanying structural transitions of self-assembled aggregates. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:284113. [PMID: 22738938 DOI: 10.1088/0953-8984/24/28/284113] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
What role does water play in the self-assembly of soft materials? To understand the correlation between the hydration state and the various self-assembled structures of a nonionic surfactant, terahertz time-domain spectroscopy has been performed for a C(12)E(5) solution with complementary use of small-angle x-ray scattering. Precise observations of the hydration state show clearly that transitions of the hydration state are accompanied by structural phase transitions of the surfactant from hexagonal to micelle to lamellae. These transitions of hydration state suggest that water is not a homogeneous solvent, and the interaction between water and the soft material is important for self-assembly.
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Affiliation(s)
- M Hishida
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Kyoto 606-8501, Japan.
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Hishida M, Tanaka K. Long-range hydration effect of lipid membrane studied by terahertz time-domain spectroscopy. PHYSICAL REVIEW LETTERS 2011; 106:158102. [PMID: 21568617 DOI: 10.1103/physrevlett.106.158102] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 03/11/2011] [Indexed: 05/30/2023]
Abstract
The hydration state of biomolecules is believed to affect their self-assembly. The hydration state of phospholipid bilayers is studied precisely by terahertz spectroscopy, by which water perturbed by a lipid membrane is detected sensitively from the observation of the relaxation dynamics of water molecules in the subpicosecond time scale. Combined with x-ray observation of the lamellar structure of the lipid, a long-range hydration effect on up to 4-5 layers of water is confirmed. Most water molecules in the lamellae fall into the hydration water, and condensation of them is also indicated.
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Affiliation(s)
- M Hishida
- Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8501, Japan
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Berntsen P, Svanberg C, Swenson J. Interplay between hydration water and headgroup dynamics in lipid bilayers. J Phys Chem B 2011; 115:1825-32. [PMID: 21302948 DOI: 10.1021/jp110899j] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, the interplay between water and lipid dynamics has been investigated by broadband dielectric spectroscopy and modulated differential scanning calorimetry (MDSC). The multilamellar lipid bilayer system 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) has been studied over a broad temperature range at three different water contents: about 3, 6, and 9 water molecules per lipid molecule. The results from the dielectric relaxation measurements show that at temperatures <250 K the lipid headgroup rotation is described by a super-Arrhenius temperature dependence at the lowest hydration level and by the Arrhenius law at the highest hydration level. This difference in the temperature dependence of the lipid headgroup rotation can be explained by the increasing interaction between the headgroups with decreasing water content, which causes their rotational motion to be more cooperative in character. The main water relaxation shows an anomalous dependence on the water content in the supercooled and glassy regime. In contrast to the general behavior of interfacial water, the water dynamics is fastest in the driest sample and its temperature dependence is best described by a super-Arrhenius temperature dependence. The best explanation for this anomalous behavior is that the water relaxation becomes more determined by fast local lipid motions than by the intrinsic water dynamics at low water contents. In support for this interpretation is the finding that the relaxation time of the main water process is faster than that in most other host systems at temperatures below 180 K. Thus, the dielectric relaxation data show clearly the strong interplay between water and lipid dynamics; the water influences the lipid dynamics and vice versa. In the MDSC data, we observe a weak enthalpy relaxation at 203 K for the driest sample and at 179 K for the most hydrated sample, attributed to the freezing-in of the lipid headgroup rotation observed in the dielectric data, since this motion reaches a time scale of about 100 s at about the same temperatures.
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Affiliation(s)
- P Berntsen
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
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Kausik R, Han S. Dynamics and state of lipid bilayer-internal water unraveled with solution state 1H dynamic nuclear polarization. Phys Chem Chem Phys 2011; 13:7732-46. [DOI: 10.1039/c0cp02512g] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Trapp M, Gutberlet T, Juranyi F, Unruh T, Demé B, Tehei M, Peters J. Hydration dependent studies of highly aligned multilayer lipid membranes by neutron scattering. J Chem Phys 2010; 133:164505. [DOI: 10.1063/1.3495973] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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42
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Kausik R, Han S. Ultrasensitive Detection of Interfacial Water Diffusion on Lipid Vesicle Surfaces at Molecular Length Scales. J Am Chem Soc 2009; 131:18254-6. [DOI: 10.1021/ja9060849] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ravinath Kausik
- Department of Chemistry and Biochemistry and Materials Research Laboratory, University of California, Santa Barbara, California 93106
| | - Songi Han
- Department of Chemistry and Biochemistry and Materials Research Laboratory, University of California, Santa Barbara, California 93106
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Jansson H, Kargl F, Fernandez-Alonso F, Swenson J. Dynamics of a protein and its surrounding environment: A quasielastic neutron scattering study of myoglobin in water and glycerol mixtures. J Chem Phys 2009; 130:205101. [DOI: 10.1063/1.3138765] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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45
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Svanberg C, Berntsen P, Johansson A, Hedlund T, Axén E, Swenson J. Structural relaxations of phospholipids and water in planar membranes. J Chem Phys 2009; 130:035101. [DOI: 10.1063/1.3054141] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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