Article
Chemistry, Multidisciplinary
Serafima Guseva, Vincent Schnapka, Wiktor Adamski, Damien Maurin, Rob W. H. Ruigrok, Nicola Salvi, Martin Blackledge
Summary: The liquid-liquid phase separation of flexible biomolecules is a common phenomenon in the formation of membraneless organelles. Nuclear magnetic resonance spectroscopy and molecular dynamics simulations were used to study the dynamics of an intrinsically disordered protein in dilute and dense phases. The results showed that the dynamics of the protein were significantly slowed down and chain-like motions dominated in the dense phase.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Biochemistry & Molecular Biology
Sebastian Fuehrer, Jana Unterhauser, Ricarda Zeindl, Reiner Eidelpes, Monica L. Fernandez-Quintero, Klaus R. Liedl, Martin Tollinger
Summary: PR-10 proteins are a major cause of food allergic reactions. This study analyzes the structural flexibility of thirteen PR-10 proteins from prevalent plant food sources and reveals that they have inherently flexible protein backbones in solution, with protein-specific extent of flexibility.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Polymer Science
Stefan Hardon, Jozef Kudelcik, Anton Baran, Ondrej Michal, Pavel Trnka, Jaroslav Hornak
Summary: In this study, nanoparticles of Al2O3 and ZnO were dispersed into a polyesterimide (PEI) matrix to prepare nanocomposite polymer. The influence of nanoparticle fillers on the complex relative permittivity was studied using dielectric frequency spectroscopy. The presence of nanoparticles in the resin changed the segmental dynamics of the polymer chain and charge distribution, resulting in higher polymer chain mobility and a shift of relaxation peaks in the spectra.
Article
Materials Science, Multidisciplinary
Julian Self, Nathan T. T. Hahn, Kristin A. A. Persson
Summary: We report the dielectric constant of 1 M LiPF6 in EC:EMC 3:7 w/w and neat EC:EMC 3:7 w/w. The EC solvent strongly coordinates with Li+ cations, leading to a loss of dielectric contribution. However, the identification of Li+ solvation shell is uncertain. The loss of free EC permittivity contribution is almost completely balanced by the positive contribution of LiPF6 salt.
ENERGY & ENVIRONMENTAL MATERIALS
(2023)
Article
Multidisciplinary Sciences
Cristina Di Carluccio, Rosa Ester Forgione, Marco Montefiori, Monica Civera, Sara Sattin, Giovanni Smaldone, K. Fukase, Y. Manabe, Paul R. Crocker, Antonio Molinaro, Roberta Marchetti, Alba Silipo
Summary: Siglecs are a group of cell-surface receptors belonging to the I-type lectin family, mostly expressed on innate immune cells, among which CD22 plays a key role in maintaining tolerance and preventing autoimmune responses. This study focused on the interaction of CD22 with sialoglycans, specifically exploring the role of N-glycolyl neuraminic acid (Neu5Gc) in this process. Findings suggested a comparable molecular recognition profile between human and murine forms of CD22, providing insights for innovative diagnostic and therapeutic methodologies in immune response modulation.
Article
Chemistry, Physical
Bence Kutus, Kenneth Wagner, Manfred Wagner, Johannes Hunger
Summary: In this study, the interaction of DMP- with different cations and water in aqueous solutions of NaDMP was investigated using dielectric relaxation and nuclear magnetic resonance spectroscopies. It was found that DMP- is weakly hydrated and weakly associated with Na+ in the absence of added salt, but forms different ion pairs in the presence of NaCl, MgCl2, or CaCl2. The dissociation rates of the ion pairs were found to follow the order Mg2+ << Ca2+ < Na+ based on concentration dependence experiments.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Physical
Sven Bodenstedt, Denis Moll, Stefan Gloeggler, Morgan W. Mitchell, Michael C. D. Tayler
Summary: The method demonstrated quantifies and manipulates nuclear spin decoherence mechanisms in zero to ultralow magnetic fields, including switching spin quantization axis and scalar pathways due to through-bond couplings. Scalar relaxation caused by H-2 near zero field can significantly limit nuclear spin polarization lifetimes. Robust trains of pulsed dc magnetic fields can switch the effective symmetry of the nuclear spin Hamiltonian, broadening the scope of hyperpolarized biomedical contrast-agent compounds used near zero field.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Aleksandra Deptuch, Malgorzata Jasiurkowska-Delaporte, Ewa Juszynska-Galazka, Anna Drzewicz, Marcin Piwowarczyk, Magdalena Urbanska, Stanislaw Baran
Summary: The study investigates the phase transitions and crystallization kinetics of the liquid crystalline compound 3FSFPhH6 using complementary methods, revealing two crystal phases and the complexity of the melt crystallization process. The melt crystallization of 3F5FPhH6 shows different mechanisms depending on temperature, which is related to the conformationally disordered phase, thermodynamic driving force, and thermal energy.
JOURNAL OF PHYSICAL CHEMISTRY B
(2022)
Article
Chemistry, Physical
Sergio Rampino, Mirco Zerbetto, Antonino Polimeno
Summary: Stochastic modeling approaches can help interpret complex molecular dynamical behaviors in solution and extract structural and dynamical data from spectroscopic observables. In this paper, the authors propose a diffusive framework based on a systematic approach to construct stochastic models, and demonstrate the usefulness of a scaled diffusion tensor as an efficient gauge of molecular flexibility.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Katja Tolkkinen, Sarah E. Mailhiot, Anne Selent, Otto Mankinen, Henning Henschel, Miika T. Nieminen, Matti Hanni, Anu M. Kantola, Timo Liimatainen, Ville-Veikko Telkki
Summary: T (1 rho) is an NMR relaxation mode sensitive to low frequency molecular motions, making it valuable in biomolecular research. We introduce a new method, SPICY, for measuring T-1 rho relaxation times. The SPICY sequence allows determination of T-1 rho within a single scan, shortening experiment time remarkably. We demonstrate the method using H-1 T-1 rho relaxation dispersion experiments and show good agreement with traditional experiments.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Gogulan Karunanithy, Harold W. Mackenzie, D. Flemming Hansen
Summary: The study introduces a method of virtual decoupling using deep neural networks, which enhances the resolution of nuclear magnetic resonance experiments and reduces the phase cycles required for experiments. This approach successfully decouples various protein NMR spectra, offering a flexible and effective solution where traditional methods may fail.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Physical
Seongkoo Kang, Kyle G. Reeves, Ivette Aguilar, Ana Gabriela Porras Gutierrez, Jean-Claude Badot, Serge Durand-Vidal, Christophe Legein, Monique Body, Antonella Iadecola, Olaf J. Borkiewicz, Olivier Dubrunfaut, Franck Fayon, Pierre Florian, Damien Dambournet
Summary: We demonstrated that the intercalation of Zn2+ ions into the interlayer space of disordered layered titanate significantly enhances the proton conductivity at room temperature. By combining various techniques, we established the relationship between structure and transport in these compounds. The insertion of Zn2+ ions maintains the local arrangement and provides a suitable model to investigate the effect of intercalated ions on transport properties. Experimental and simulation results showed that the proton motion is facilitated by the interactions between water molecules and Zn2+ ions. This study provides insights into the ion-water interactions that mediate ionic transport and has implications for the design of ionic conductors for energy storage applications.
CHEMISTRY OF MATERIALS
(2022)
Article
Biochemistry & Molecular Biology
Xiaomin Chen, Hexuan Gao, Dong Long
Summary: This study quantitatively measured and validated the internal dynamics of Ras complexed with a slowly hydrolyzable GTP analogue, GTP gamma S, which significantly increased the lifetime of active Ras. It was found that GTP gamma S can better mimic the exchange kinetics and reproduce the natural dynamics network in active Ras, indicating its potential use in the development of allosteric inhibitors.
Article
Materials Science, Ceramics
Hamza Assad, Mohamed Kharroubi
Summary: This study presents a detailed characterization of the dielectric properties of a new zinc sodium phosphate glass doped with different mole ratios of cobalt. The electrical characterizations were performed at different frequencies and temperatures using alternating current impedance spectroscopy, with the data analyzed according to the Cole Cole model equation.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2021)
Article
Chemistry, Physical
Yael Beilinson, Verena Schiller, Julia Regentin, Jorge H. Melillo, Anna Greenbaum, Tatiana Antropova, Silvina Cerveny, Michael Vogel, Yuri Feldman
Summary: The dynamics of water confined in mesoporous materials were studied using a combination of techniques including broadband dielectric spectroscopy, nuclear magnetic resonance, and differential scanning calorimetry. The results show that water confined in MIP samples exhibits a dynamic crossover at around 180 K, while water confined in MAP samples does not show any changes in relaxation behavior. The crossover temperature is found to depend on the hydration level. Below the crossover temperature, water reorientation is isotropic and the dielectric relaxation strength follows a solid-like behavior, while above the crossover temperature, water reorientation is related to long-range diffusion and the dielectric relaxation strength follows a liquid-like behavior. The results are also consistent with a glass transition near 180 K.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Physical
M. A. Belyanchikov, Z. Bedran, M. Savinov, P. Bednyakov, P. Proschek, J. Prokleska, V. A. Abalmasov, E. S. Zhukova, V. G. Thomas, A. Dudka, A. Zhugayevych, J. Petzelt, A. S. Prokhorov, V. B. Anzin, R. K. Kremer, J. K. H. Fischer, P. Lunkenheimer, A. Loidl, E. Uykur, M. Dressel, B. Gorshunov
Summary: This study investigates the collective modes and single-particle excitations of water molecules confined within nanocages using comprehensive broad-band dielectric spectroscopy, specific heat studies, and molecular dynamics and Monte Carlo simulations. The results show that the confined water molecules exhibit rich anisotropic temperature-dependent excitations, and a ferroelectric order-disorder phase transition is confirmed at approximately 3 K.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Julian Wagner, Anuja Sahasrabudhe, Rolf B. Versteeg, Lena Wysocki, Zhe Wang, Vladimir Tsurkan, Alois Loidl, Daniel Khomskii, Hamoon Hedayat, Paul H. M. van Loosdrecht
Summary: The evolution of the zigzag order parameter in alpha-RuCl3 is studied, revealing the presence of metamagnetic transitions and the emergence of an intermediate phase induced by a magnetic field. The results provide a quantitative description of the bond-anisotropic interactions in alpha-RuCl3.
NPJ QUANTUM MATERIALS
(2022)
Article
Multidisciplinary Sciences
Jiaqi Zhu, Xavier Salvatella, Paul Robustelli
Summary: This study elucidates the atomically detailed binding mechanisms of small molecule drugs to the intrinsically disordered region of the androgen receptor, providing insights for developing more potent inhibitors and strategies for disordered protein drug design.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Peter Lunkenheimer, Alois Loidl, Birte Riechers, Alessio Zaccone, Konrad Samwer
Summary: The Lindemann criterion applies to the melting of crystals but not to glasses. There is a universal relationship between glass temperature and thermal expansion. The thermal expansion coefficient of glasses behaves differently from crystals, indicating a liquid-solid cross-over in glasses.
Article
Chemistry, Physical
P. Lunkenheimer, A. Loidl, G. P. Johari
Summary: By using dielectric spectroscopy, we investigated dipolar relaxations, dc conductivity, and polar order in AgCN. The conductivity contribution dominates at high temperatures and low frequencies, originating from silver ions' mobility. We observed dipolar relaxation of CN- ions and found a phase with quadrupolar order in AgCN, indicating dipolar head-to-tail disorder of the CN- ions at elevated temperatures. Under about 475 K, a long-range polar order of the CN dipole moments emerges.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Verena Schiller, Katharina Knippen, Alois Loidl, Peter Lunkenheimer, Dirk Volkmer, Michael Vogel
Summary: We used H-2 nuclear magnetic resonance (NMR) to investigate the reorientation and diffusion of water in the metal-organic framework MFU-4l. The study revealed that the rotational correlation times follow different relations above and below certain temperatures, with a continuous evolution in between. The NMR results were consistent with previous broadband dielectric spectroscopy (BDS) data on water in a similar framework. The water dynamics at low temperatures did not fully restore ergodicity, suggesting the presence of spatially heterogeneous water properties.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Cell Biology
Neus Sanfeliu-Cerdan, Frederic Catala-Castro, Borja Mateos, Carla Garcia-Cabau, Maria Ribera, Iris Ruider, Montserrat Porta-de-la-Riva, Adria Canals-Calderon, Stefan Wieser, Xavier Salvatella, Michael Krieg
Summary: This study reveals that the material properties of biomolecular condensates can change with time, and the MEC-2/stomatin condensates undergo a rigidity phase transition from fluid-like to solid-like, facilitating transport and mechanotransduction. This finding suggests that the rigidity phase transition has a physiological role in force transmission in mechanosensitive neurons.
NATURE CELL BIOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Jennifer Schnabel, Arthur Schulz, Peter Lunkenheimer, Dirk Volkmer
Summary: By modifying the organic ligands of metal-organic framework with dipolar units, they can be used in various applications such as sensor systems and gas permeation switching. The dipolar linkers in the organic ligands can rotate within specific temperature and frequency ranges. Through dielectric spectroscopy and computational simulation, the authors investigate the behavior of benzothiadiazole units in the carboxylate-based MOFs ZJNU-40 and JLU-Liu30, revealing significant reorientational relaxation dynamics and glasslike freezing characteristics upon cooling. Metal-organic frameworks containing rotatable dipolar linkers are important for sensor systems and gas separation.
COMMUNICATIONS CHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
M. Winkler, L. Prodan, V Tsurkan, P. Lunkenheimer, I Kezsmarki
Summary: This study presents data on the dielectric, polarization, resistivity, specific-heat, and magnetic susceptibility properties of single crystals of GaNb4Se8 and GaTa4Se8. The findings suggest the presence of antipolar order and dipolar relaxation dynamics in these compounds. The polarization measurements indicate the weak ferroelectric ordering in GaNb4Se8. The temperature-dependent resistivity points to a fundamental change in the electronic structure or the charge transport mechanism.
Article
Physics, Fluids & Plasmas
K. L. Ngai, S. Capaccioli, P. Lunkenheimer, A. Loidl
Summary: This paper critically compares four major interpretations to identify the most plausible interpretation of the relaxation processes observed in the dielectric spectra of glycerol.
Article
Chemistry, Physical
Julian Wagner, Anuja Sahasrabudhe, Rolf Versteeg, Zhe Wang, Vladimir Tsurkan, Alois Loidl, Hamoon Hedayat, Paul H. M. van Loosdrecht
Summary: We have conducted time-resolved magneto-optical spectroscopy on the magnetic Mott-Hubbard-insulating Kitaev spin liquid candidate α-RuCl3 to investigate the non-equilibrium dynamics of its antiferromagnetically ordered zigzag groundstate after photoexcitation. Our findings reveal the dynamical interplay of charge excitations with the zigzag ordered state on ultrashort time scales, and the existence of a long-lived non-thermal antiferromagnetic spin-disordered state. These results have implications for the study of nonequilibrium states in strongly correlated materials.
FARADAY DISCUSSIONS
(2022)
