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Listyarini R, Kriesche BM, Hofer TS. Characterization of the Coordination and Solvation Dynamics of Solvated Systems─Implications for the Analysis of Molecular Interactions in Solutions and Pure H 2O. J Chem Theory Comput 2024; 20:3028-3045. [PMID: 38595064 PMCID: PMC11044269 DOI: 10.1021/acs.jctc.4c00162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/26/2024] [Accepted: 03/28/2024] [Indexed: 04/11/2024]
Abstract
The characterization of solvation shells of atoms, ions, and molecules in solution is essential to relate solvation properties to chemical phenomena such as complex formation and reactivity. Different definitions of the first-shell coordination sphere from simulation data can lead to potentially conflicting data on the structural properties and associated ligand exchange dynamics. The definition of a solvation shell is typically based on a given threshold distance determined from the respective solute-solvent pair distribution function g(r) (i.e., GC). Alternatively, a nearest neighbor (NN) assignment based on geometric properties of the coordination complex without the need for a predetermined cutoff criterion, such as the relative angular distance (RAD) or the modified Voronoi (MV) tessellation, can be applied. In this study, the effect of different NN algorithms on the coordination number and ligand exchange dynamics evaluated for a series of monatomic ions in aqueous solution, carbon dioxide in aqueous and dichloromethane solutions, and pure liquid water has been investigated. In the case of the monatomic ions, the RAD approach is superior in achieving a well separated definition of the first solvation layer. In contrast, the MV algorithm provides a better separation of the NNs from a molecular point of view, leading to better results in the case of solvated CO2. When analyzing the coordination environment in pure water, the cutoff-based GC framework was found to be the most reliable approach. By comparison of the number of ligand exchange reactions and the associated mean ligand residence times (MRTs) with the properties of the coordination number autocorrelation functions, it is shown that although the average coordination numbers are sensitive to the different definitions of the first solvation shell, highly consistent estimates for the associated MRT of the solvated system are obtained in the majority of cases.
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Affiliation(s)
- Risnita
Vicky Listyarini
- Institute
of General, Inorganic and Theoretical Chemistry Center for Chemistry
and Biomedicine, University of Innsbruck Innrain 80-82, A-6020 Innsbruck, Austria
- Chemistry
Education Study Program Sanata Dharma University, Yogyakarta 55282, Indonesia
| | - Bernhard M. Kriesche
- Institute
of General, Inorganic and Theoretical Chemistry Center for Chemistry
and Biomedicine, University of Innsbruck Innrain 80-82, A-6020 Innsbruck, Austria
| | - Thomas S. Hofer
- Institute
of General, Inorganic and Theoretical Chemistry Center for Chemistry
and Biomedicine, University of Innsbruck Innrain 80-82, A-6020 Innsbruck, Austria
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2
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Bharmoria P, Tietze AA, Mondal D, Kang TS, Kumar A, Freire MG. Do Ionic Liquids Exhibit the Required Characteristics to Dissolve, Extract, Stabilize, and Purify Proteins? Past-Present-Future Assessment. Chem Rev 2024; 124:3037-3084. [PMID: 38437627 PMCID: PMC10979405 DOI: 10.1021/acs.chemrev.3c00551] [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: 07/31/2023] [Revised: 02/08/2024] [Accepted: 02/19/2024] [Indexed: 03/06/2024]
Abstract
Proteins are highly labile molecules, thus requiring the presence of appropriate solvents and excipients in their liquid milieu to keep their stability and biological activity. In this field, ionic liquids (ILs) have gained momentum in the past years, with a relevant number of works reporting their successful use to dissolve, stabilize, extract, and purify proteins. Different approaches in protein-IL systems have been reported, namely, proteins dissolved in (i) neat ILs, (ii) ILs as co-solvents, (iii) ILs as adjuvants, (iv) ILs as surfactants, (v) ILs as phase-forming components of aqueous biphasic systems, and (vi) IL-polymer-protein/peptide conjugates. Herein, we critically analyze the works published to date and provide a comprehensive understanding of the IL-protein interactions affecting the stability, conformational alteration, unfolding, misfolding, and refolding of proteins while providing directions for future studies in view of imminent applications. Overall, it has been found that the stability or purification of proteins by ILs is bispecific and depends on the structure of both the IL and the protein. The most promising IL-protein systems are identified, which is valuable when foreseeing market applications of ILs, e.g., in "protein packaging" and "detergent applications". Future directions and other possibilities of IL-protein systems in light-harvesting and biotechnology/biomedical applications are discussed.
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Affiliation(s)
- Pankaj Bharmoria
- CICECO
- Aveiro Institute of Materials, Chemistry Department, University of Aveiro, 3810-193 Aveiro, Portugal
- Department
of Smart Molecular, Inorganic and Hybrid Materials, Institute of Materials Science of Barcelona (ICMAB-CSIC), 08193 Bellaterra, Barcelona, Spain
- Department
of Chemistry and Molecular Biology, Wallenberg Centre for Molecular
and Translational Medicine, University of
Gothenburg, SE-412 96 Göteborg, Sweden
| | - Alesia A. Tietze
- Department
of Chemistry and Molecular Biology, Wallenberg Centre for Molecular
and Translational Medicine, University of
Gothenburg, SE-412 96 Göteborg, Sweden
| | - Dibyendu Mondal
- CICECO
- Aveiro Institute of Materials, Chemistry Department, University of Aveiro, 3810-193 Aveiro, Portugal
- Institute
of Plant Genetics (IPG), Polish Academy of Sciences, Strzeszyńska 34, 60-479 Poznań, Poland
- Centre
for Nano and Material Sciences, JAIN (Deemed-to-be
University), Jain Global
Campus, Bangalore 562112, India
| | - Tejwant Singh Kang
- Department
of Chemistry, UGC Center for Advance Studies-II,
Guru Nanak Dev University (GNDU), Amritsar 143005, Punjab, India
| | - Arvind Kumar
- Salt
and Marine Chemicals Division, CSIR-Central
Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar 364002, Gujarat, India
| | - Mara G Freire
- CICECO
- Aveiro Institute of Materials, Chemistry Department, University of Aveiro, 3810-193 Aveiro, Portugal
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Depenveiller C, Baud S, Belloy N, Bochicchio B, Dandurand J, Dauchez M, Pepe A, Pomès R, Samouillan V, Debelle L. Structural and physical basis for the elasticity of elastin. Q Rev Biophys 2024; 57:e3. [PMID: 38501287 DOI: 10.1017/s0033583524000040] [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: 03/20/2024]
Abstract
Elastin function is to endow vertebrate tissues with elasticity so that they can adapt to local mechanical constraints. The hydrophobicity and insolubility of the mature elastin polymer have hampered studies of its molecular organisation and structure-elasticity relationships. Nevertheless, a growing number of studies from a broad range of disciplines have provided invaluable insights, and several structural models of elastin have been proposed. However, many questions remain regarding how the primary sequence of elastin (and the soluble precursor tropoelastin) governs the molecular structure, its organisation into a polymeric network, and the mechanical properties of the resulting material. The elasticity of elastin is known to be largely entropic in origin, a property that is understood to arise from both its disordered molecular structure and its hydrophobic character. Despite a high degree of hydrophobicity, elastin does not form compact, water-excluding domains and remains highly disordered. However, elastin contains both stable and labile secondary structure elements. Current models of elastin structure and function are drawn from data collected on tropoelastin and on elastin-like peptides (ELPs) but at the tissue level, elasticity is only achieved after polymerisation of the mature elastin. In tissues, the reticulation of tropoelastin chains in water defines the polymer elastin that bears elasticity. Similarly, ELPs require polymerisation to become elastic. There is considerable interest in elastin especially in the biomaterials and cosmetic fields where ELPs are widely used. This review aims to provide an up-to-date survey of/perspective on current knowledge about the interplay between elastin structure, solvation, and entropic elasticity.
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Affiliation(s)
- Camille Depenveiller
- UMR URCA/CNRS 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), UFR Sciences Exactes et Naturelles, SFR CAP Santé, Université de Reims Champagne-Ardenne, Reims, France
- Unité de Génie Enzymatique et Cellulaire UMR 7025 CNRS, Université de Picardie Jules Verne, Amiens, France
| | - Stéphanie Baud
- UMR URCA/CNRS 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), UFR Sciences Exactes et Naturelles, SFR CAP Santé, Université de Reims Champagne-Ardenne, Reims, France
| | - Nicolas Belloy
- UMR URCA/CNRS 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), UFR Sciences Exactes et Naturelles, SFR CAP Santé, Université de Reims Champagne-Ardenne, Reims, France
| | - Brigida Bochicchio
- Laboratory of Bioinspired Materials, Department of Science, University of Basilicata, Potenza, Italy
| | - Jany Dandurand
- CIRIMAT UMR 5085, Université Paul Sabatier, Université de Toulouse, Toulouse, France
| | - Manuel Dauchez
- UMR URCA/CNRS 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), UFR Sciences Exactes et Naturelles, SFR CAP Santé, Université de Reims Champagne-Ardenne, Reims, France
| | - Antonietta Pepe
- Laboratory of Bioinspired Materials, Department of Science, University of Basilicata, Potenza, Italy
| | - Régis Pomès
- Molecular Medicine, Hospital for Sick Children, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Valérie Samouillan
- CIRIMAT UMR 5085, Université Paul Sabatier, Université de Toulouse, Toulouse, France
| | - Laurent Debelle
- UMR URCA/CNRS 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), UFR Sciences Exactes et Naturelles, SFR CAP Santé, Université de Reims Champagne-Ardenne, Reims, France
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4
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Markovitsi D. Processes triggered in guanine quadruplexes by direct absorption of UV radiation: From fundamental studies toward optoelectronic biosensors. Photochem Photobiol 2024; 100:262-274. [PMID: 37365765 DOI: 10.1111/php.13826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/28/2023]
Abstract
Guanine quadruplexes (GQs) are four-stranded DNA/RNA structures exhibiting an important polymorphism. During the past two decades, their study by time-resolved spectroscopy, from femtoseconds to milliseconds, associated to computational methods, shed light on the primary processes occurring when they absorb UV radiation. Quite recently, their utilization in label-free and dye-free biosensors was explored by a few groups. In view of such developments, this review discusses the outcomes of the fundamental studies that could contribute to the design of future optoelectronic biosensors using fluorescence or charge carriers stemming directly from GQs, without mediation of other molecules, as it is the currently the case. It explains how the excited state relaxation influences both the fluorescence intensity and the efficiency of low-energy photoionization, occurring via a complex mechanism. The corresponding quantum yields, determined with excitation at 266/267 nm, fall in the range of (3.0-9.5) × 10-4 and (3.2-9.2) × 10-3 , respectively. These values, significantly higher than the corresponding values found for duplexes, depend strongly on certain structural factors (molecularity, metal cations, peripheral bases, number of tetrads …) which intervene in the relaxation process. Accordingly, these features can be tuned to optimize the desired signal.
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Affiliation(s)
- Dimitra Markovitsi
- CNRS, Institut de Chimie Physique, UMR8000, Université Paris-Saclay, Orsay, France
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5
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Silva WGDP, Poonia T, van Wijngaarden J. Exploring the conformational landscape, hydrogen bonding, and internal dynamics in the diallyl ether and diallyl sulfide monohydrates. J Chem Phys 2024; 160:044302. [PMID: 38258923 DOI: 10.1063/5.0180901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 01/01/2024] [Indexed: 01/24/2024] Open
Abstract
The conformational spaces of the diallyl ether (DAE) and diallyl sulfide (DAS) monohydrates were explored using rotational spectroscopy from 6 to 19 GHz. Calculations at the B3LYP-D3(BJ)/aug-cc-pVTZ level suggested significant differences in their conformational behavior, with DAE-w exhibiting 22 unique conformers and DAS-w featuring three stable structures within 6 kJ mol-1. However, only transitions from the lowest energy conformer of each were experimentally observed. Spectral analysis confirmed that binding with water does not alter the conformational preference for the lowest energy structure of the monomers, but it does influence the relative stabilities of all other conformers, particularly in the case of DAE. Non-covalent interaction and quantum theory of atoms in molecules analyses showed that the observed conformer for each complex is stabilized by two intermolecular hydrogen bonds (HBs), where water primarily interacts with the central oxygen or sulfur atom of the diallyl compounds, along with secondary interactions involving the allyl groups. The nature of these interactions was further elucidated using symmetry-adapted perturbation theory, which suggests that the primary HB interaction with S in DAS is weaker and more dispersive in nature compared to the primary HB in DAE. This supports the experimental observation of a tunneling splitting exclusively in the rotational spectrum of DAS-w, as the weaker contact allows water to undergo internal motions within the complex, as shown based on calculated transition state structures for possible tunneling pathways.
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Affiliation(s)
- Weslley G D P Silva
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany
| | - Tamanna Poonia
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Jennifer van Wijngaarden
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
- Department of Chemistry, York University, Toronto, Ontario M3J 1P3, Canada
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6
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Majumdar S, Rastogi H, Chowdhury PK. Bridging Soft Interaction and Excluded Volume in Crowded Milieu through Subtle Protein Dynamics. J Phys Chem B 2024; 128:716-730. [PMID: 38226816 DOI: 10.1021/acs.jpcb.3c07266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
The impact of macromolecular crowding on biological macromolecules has been elucidated through the excluded volume phenomenon and soft interactions. However, it has often been difficult to provide a clear demarcation between the two regions. Here, using temperature-dependent dynamics (local and global) of the multidomain protein human serum albumin (HSA) in the presence of commonly used synthetic crowders (Dextran 40, PEG 8, Ficoll 70, and Dextran 70), we have shown the presence of a transition that serves as a bridge between the soft and hard regimes. The bridging region is independent of the crowder identity and displays no apparent correlation with the critical overlap concentration of the polymeric crowding agents. Moreover, the dynamics of domains I and II and the protein gating motion respond differently, thereby bringing to the fore the asymmetry underlying the crowder influence on HSA. In addition, solvent-coupled and decoupled protein motions indicate the heterogeneity of the dynamic landscape in the crowded milieu. We also propose an intriguing correlation between protein stability and dynamics, with increased global stability being accompanied by eased local domain motion.
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Affiliation(s)
- Shubhangi Majumdar
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Harshita Rastogi
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Pramit K Chowdhury
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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7
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Li P, Yang X, Chen F, Wang D, Hao D, Xu Z, Qiu M, He S, Xia F, Tian Y. Confined Water Dominates Ion/Molecule Transport in Hydrogel Nanochannels. NANO LETTERS 2024; 24:897-904. [PMID: 38193898 DOI: 10.1021/acs.nanolett.3c04107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
Current artificial nanochannels rely more on charge interactions for intelligent mass transport. Nevertheless, popular charged nanochannels would lose their advantages in long-term applications. Confined water, an indispensable transport medium in biological nanochannels, dominating the transport process in the uncharged nanochannels perfectly provides a new perspective. Herein, we achieve confined-water-dominated mass transport in hydrogel nanochannels (HNCs) constructed by in situ photopolymerization of acrylic acid (PAA) hydrogel in anodic alumina (AAO) nanochannels. HNCs show selectivity to Na+ transport and a high transport rate of molecules after introducing Na+/Li+, compared with other alkali metal ions like Cs+/K+. The mechanism given by ATR-FTIR shows that the hydrogen-bonding structure of confined water in HNCs is destabilized by Na+/Li+, which facilitates mass transport, but is constrained by Cs+/K+, resulting in transport inhibition. This work elucidates the relationship between confined water and mass transport in uncharged nanochannels while also presenting a strategy for designing functional nanochannel devices.
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Affiliation(s)
- Peijia Li
- Laboratory of Bio-Inspired Materials and Interface Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xiaotao Yang
- Laboratory of Bio-Inspired Materials and Interface Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Fengxiang Chen
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies, Hubei Key Laboratory of Digital Textile Equipment, Wuhan Textile University, Wuhan 430200, People's Republic of China
| | - Dianyu Wang
- School of Chemical Engineering, Zhengzhou University, Zhengzhou 450001, People's Republic of China
| | - Dezhao Hao
- Laboratory of Bio-Inspired Materials and Interface Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Zhe Xu
- Laboratory of Bio-Inspired Materials and Interface Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Ming Qiu
- Laboratory of Bio-Inspired Materials and Interface Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Shaofan He
- Laboratory of Bio-Inspired Materials and Interface Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Fan Xia
- State Key Laboratory of Biogeology and Environmental Geology, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430078, People's Republic of China
| | - Ye Tian
- Laboratory of Bio-Inspired Materials and Interface Sciences, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, People's Republic of China
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8
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Khan T, Das N, Negi KS, Bhowmik S, Sen P. Understanding the intricacy of protein in hydrated deep eutectic solvent: Solvation dynamics, conformational fluctuation dynamics, and stability. Int J Biol Macromol 2023; 253:127100. [PMID: 37778586 DOI: 10.1016/j.ijbiomac.2023.127100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 09/21/2023] [Accepted: 09/25/2023] [Indexed: 10/03/2023]
Abstract
Deep eutectic solvents (DESs) are potential biocatalytic media due to their easy preparation, fine-tuneability, biocompatibility, and most importantly, due to their ability to keep protein stable and active. However, there are many unanswered questions and gaps in our knowledge about how proteins behave in these alternate media. Herein, we investigated solvation dynamics, conformational fluctuation dynamics, and stability of human serum albumin (HSA) in 0.5 Acetamide/0.3 Urea/0.2 Sorbitol (0.5Ac/0.3Ur/0.2Sor) DES of varying concentrations to understand the intricacy of protein behaviour in DES. Our result revealed a gradual decrease in the side-chain flexibility and thermal stability of HSA beyond 30 % DES. On the other hand, the associated water dynamics around domain-I of HSA decelerate only marginally with increasing DES content, although viscosity rises considerably. We propose that even though macroscopic solvent properties are altered, a protein feels only an aqueous type of environment in the presence of DES. This is probably the first experimental study to delineate the role of the associated water structure of the enzyme for maintaining its stability inside DES. Although considerable effort is necessary to generalize such claims, it might serve as the basis for understanding why proteins remain stable and active in DES.
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Affiliation(s)
- Tanmoy Khan
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, UP, India
| | - Nilimesh Das
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, UP, India
| | - Kuldeep Singh Negi
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, UP, India
| | - Suman Bhowmik
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, UP, India
| | - Pratik Sen
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, UP, India.
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9
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Tan J, Wang M, Zhang J, Ye S. Determination of the Thickness of Interfacial Water by Time-Resolved Sum-Frequency Generation Vibrational Spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:18573-18580. [PMID: 38051545 DOI: 10.1021/acs.langmuir.3c02906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
The physics and chemistry of a charged interface are governed by the structure of the electrical double layer (EDL). Determination of the interfacial water thickness (diw) of the charged interface is crucial to quantitatively describe the EDL structure, but it can be utilized with very scarce experimental methods. Here, we propose and verify that the vibrational relaxation time (T1) of the OH stretching mode at 3200 cm-1, obtained by time-resolved sum frequency generation vibrational spectroscopy with ssp polarizations, provides an effective tool to determine diw. By investigating the T1 values at the SiO2/NaCl solution interface, we established a time-space (T1-diw) relationship. We find that water has a T1 lifetime of ≥0.5 ps for diw ≤ 3 Å, while it displays bulk-like dynamics with T1 ≤ 0.2 ps for diw ≥ 9 Å. T1 decreases as diw increases from ∼3 Å to 9 Å. The hydration water at the DPPG lipid bilayer and LK15β protein interfaces has a thickness of ≥9 Å and shows a bulk-like feature. The time-space relationship will provide a novel tool to pattern the interfacial topography and heterogeneity in Ångstrom-depth resolution by imaging the T1 values.
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Affiliation(s)
- Junjun Tan
- Hefei National Research Center for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Mengmeng Wang
- Hefei National Research Center for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Jiahui Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Shuji Ye
- Hefei National Research Center for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
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10
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Ishigaki M, Kato Y, Chatani E, Ozaki Y. Variations in the Protein Hydration and Hydrogen-Bond Network of Water Molecules Induced by the Changes in the Secondary Structures of Proteins Studied through Near-Infrared Spectroscopy. J Phys Chem B 2023; 127:7111-7122. [PMID: 37477646 DOI: 10.1021/acs.jpcb.3c01803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
This study investigated how the secondary structural changes of proteins in aqueous solutions affect their hydration and the hydrogen-bond network of water molecules using near-infrared (NIR) spectroscopy. The aqueous solutions of three types of proteins, i.e., ovalbumin, β-lactoglobulin, and bovine serum albumin, were denatured by heating, and changes in the NIR bands of water reflecting the states of hydrogen bonds induced via protein secondary structural changes were investigated. On heating, the intermolecular hydrogen bonds between water molecules as well as between water and protein molecules were broken, and protein molecules were no longer strongly bound by the surrounding water molecules. Consequently, the denaturation was observed to proceed depending on the thermodynamic properties of the proteins. When the aqueous solutions of proteins were cooled after denaturation, the hydrogen-bond network was reformed. However, the state of protein hydration was changed owing to the secondary structural changes of proteins, and the variation patterns were different depending on the protein species. These changes in protein hydration may be derived from the differences in the surface charges of proteins. The elucidation of the mechanism of protein hydration and the formation of the hydrogen-bond network of water molecules will afford a comprehensive understanding of the protein functioning and dysfunctioning derived from the structural changes in proteins.
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Affiliation(s)
- Mika Ishigaki
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
| | - Yoshiki Kato
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
| | - Eri Chatani
- Department of Chemistry, Graduate School of Science, Kobe University, Nada, Kobe 657-8501, Japan
| | - Yukihiro Ozaki
- School of Biological and Environmental Sciences, Kwansei Gakuin University, 1 Gakuen-Uegahara, Sanda, Hyogo 669-1330, Japan
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Yang B, Ren P, Xing L, Wang S, Sun C. Roles of hydrogen bonding interactions and hydrophobic effects on enhanced water structure in aqueous solutions of amphiphilic organic molecules. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 296:122605. [PMID: 37004424 DOI: 10.1016/j.saa.2023.122605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 02/15/2023] [Accepted: 03/06/2023] [Indexed: 06/19/2023]
Abstract
Insights into the solute-induced water structural transformations are essential to understand the role of water in biological and chemical reaction processes. Herein, the structural changes in water induced by amphiphilic organic molecules were investigated using concentration-dependent derivative Raman spectroscopy (DRS) combined with two-dimensional Raman correlation spectroscopy (2D Raman-COS). We shall restrict our attention in this work to binary mixtures of water with dimethyl sulfoxide (DMSO), acetone, and isopropanol (IPA), all of which have similar chemical structures. The spectral changes in O:H and OH stretching modes illustrate that the solute molecules induce an enhancement of the water structure in dilute solutions, where the enhanced degree of water structure is closely related to the size of the dipole moment of organic molecules. In addition, the transformations of solute-induced water-specific structures were evaluated by 2D Raman-COS, which shows that the strong hydrogen bond (H-bond) structure of water is more sensitive to organic molecules and induces a transition to the weak H-bond structure of water.
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Affiliation(s)
- Bo Yang
- Coherent Light and Atomic and Molecular Spectroscopy Laboratory, College of Physics, Jilin University, Changchun 130012, China
| | - Panpan Ren
- Coherent Light and Atomic and Molecular Spectroscopy Laboratory, College of Physics, Jilin University, Changchun 130012, China
| | - Lu Xing
- Coherent Light and Atomic and Molecular Spectroscopy Laboratory, College of Physics, Jilin University, Changchun 130012, China.
| | - Shenghan Wang
- Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, China.
| | - Chenglin Sun
- Coherent Light and Atomic and Molecular Spectroscopy Laboratory, College of Physics, Jilin University, Changchun 130012, China; Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, China.
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12
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Le Breton G, Bonhomme O, Benichou E, Loison C. Liquid Water: When Hyperpolarizability Fluctuations Boost and Reshape the Second Harmonic Scattering Intensities. J Phys Chem Lett 2023; 14:4158-4163. [PMID: 37104636 DOI: 10.1021/acs.jpclett.3c00546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Second harmonic scattering (SHS) is a method of choice to investigate the molecular structure of liquids. While a clear interpretation of SHS intensity exists for diluted solutions of dyes, the scattering due to solvents remains difficult to interpret quantitatively. Here, we report a quantum mechanics/molecular mechanics (QM/MM) approach to model the polarization-resolved SHS intensity of liquid water, quantifying different contributions to the signal. We point out that the molecular hyperpolarizability fluctuations and correlations cannot be neglected. The intermolecular orientational and hyperpolarizability correlations up to the third solvation layer strongly increase the scattering intensities and modulate the polarization-resolved oscillation that is predicted here by QM/MM without fitting parameters. Our approach can be generalized to other pure liquids to provide a quantitative interpretation of SHS intensities in terms of short-range molecular ordering.
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Affiliation(s)
- Guillaume Le Breton
- Univ Lyon, Univ Claude Bernard Lyon1, CNRS, Light and Matter Institute, F-69622 Villeurbanne, France
| | - Oriane Bonhomme
- Univ Lyon, Univ Claude Bernard Lyon1, CNRS, Light and Matter Institute, F-69622 Villeurbanne, France
| | - Emmanuel Benichou
- Univ Lyon, Univ Claude Bernard Lyon1, CNRS, Light and Matter Institute, F-69622 Villeurbanne, France
| | - Claire Loison
- Univ Lyon, Univ Claude Bernard Lyon1, CNRS, Light and Matter Institute, F-69622 Villeurbanne, France
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13
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Mitra S, Basak M. Nonequilibrium Dynamics of Transient Autoelectrophoresis and Effect of Surface Heterogeneity. J Phys Chem B 2023; 127:2034-2043. [PMID: 36853743 DOI: 10.1021/acs.jpcb.2c09119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Nonuniform proton flux around a reactive Janus particle as a result of zone selective heterogeneous surface reaction leads to the formation of asymmetric electrical double layers (EDLs) which assists in generating a proximate electric field dipole around the Janus particle to initiate autoelectrophoretic migration. To estimate the force of the autoelectrophoretic motion of such Janus particles, a mathematical model is set up taking Poisson-Nernst-Plank (PNP) equations coupled with the Navier-Stokes (NS) equations with appropriate boundary conditions. To track the actual motion of these particles, we employ moving deforming mesh and fluid-structure interactions (fsi) of COMSOL Multiphysics while a finite element method is deployed for solving the set of modeled equations. At the outset, transient genesis of the electric field around the particle owing to the nonuniform proton flux has been explored. We further explore the detailed unsteady particle dynamics of the autoelectrophoretic motion with the help of fluid structure interaction physics. It has been observed that the concept of perfect ionic equilibrium in autoelectrophoretic motion is hard to achieve. The autoelectrophoretic particle undergoes continuous change in terms of the ionic concentration around it, speed of the particle, and the transient electric field gradient across the particle. The parametric variation of proton flux reveals that at a relatively lower proton flux a quasi-equilibrium state can be achieved, whereas for higher proton flux the phenomenon can be a pure nonequilibrium case. This parametric study has been done to support the transient dynamics. It has also been shown that the presence of chemical heterogeneity on the particle surface can alter the dynamics of the particle significantly, and the chemical heterogeneity can be used as a tool to control directionality and tuning speed of autoelectrophoretic motion.
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Affiliation(s)
- Shirsendu Mitra
- Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, India.,Pioneer of Success Online Educational Institute, Halisahar 743134, West Bengal, India
| | - Mitali Basak
- Centre for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.,Pioneer of Success Online Educational Institute, Halisahar 743134, West Bengal, India
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14
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Li J, Wang X, Zhang X, Chen J, Wang H, Tian X, Xu X, Gou Q. Stepwise hydrations of anhydride tuned by hydrogen bonds: rotational study on maleic anhydride-(H 2O) 1-3. Phys Chem Chem Phys 2023; 25:4611-4616. [PMID: 36723184 DOI: 10.1039/d2cp05861h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The rotational spectra of maleic anhydride-(H2O)1-3 have been investigated for the first time by using pulsed jet Fourier transform microwave spectroscopy with complementary computational analyses. The experimental evidence points out that water tends to self-aggregate with hydrogen bonds and form homodromic cycles. Differences in bond lengths and charge distribution between the two carbonyl sites have been observed upon stepwise hydrations, which might further introduce a selectivity on the nucleophilic attack sites of hydrolysis. This study provides an important insight into the incipient solvation process (microsolvation) of maleic anhydride in water by understanding the cooperation and rearrangement of intermolecular hydrogen bonds in its stepwise hydrates.
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Affiliation(s)
- Jiayi Li
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, China.
| | - Xiujuan Wang
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, China.
| | - Xinyue Zhang
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, China.
| | - Junhua Chen
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, China. .,School of Pharmacy, Guizhou Medical University, Guiyang, 550000, Guizhou, China
| | - Hao Wang
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, China.
| | - Xiao Tian
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, China.
| | - Xuefang Xu
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, China.
| | - Qian Gou
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331, Chongqing, China.
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15
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Structural and quantitative analysis of intermolecular solid-state interactions in cocrystals obtained from nucleobases and methylxanthines with gallic acid. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2023.135074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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16
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Impact and Structure of Water in Aqueous Octanol Mixtures: Hz-GHz Dielectric Relaxation Measurements and Computer Simulations. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2023.114600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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17
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Sen S, Datta A, Tahara T. Memorial Viewpoint for Kankan Bhattacharyya. J Phys Chem B 2023; 127:3-5. [PMID: 36583852 DOI: 10.1021/acs.jpcb.2c08803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Sobhan Sen
- School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Anindya Datta
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Tahei Tahara
- Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,Ultrafast Spectroscopy Research Team, RIKEN Center for Advanced Photonics (RAP), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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18
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Crowder M, Tahiry F, Lizarraga I, Rodriguez S, Peña N, Sharma AK. Computatiaonal Analysis of Water Dynamics in AOT Reverse Micelles. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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19
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Effect of hemoglobin hydration on the physical properties of erythrocyte cytoplasm and whole blood. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.141560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Monitoring the effect of SDS on the solvation dynamics and structural conformation of β-casein. J CHEM SCI 2022. [DOI: 10.1007/s12039-022-02092-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Dynamics of a PEG based polymer gel Electrolyte: A combined frequency dependent dielectric relaxation and Time-resolved fluorescence spectroscopic study. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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22
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The Journey of 1-Keto-1,2,3,4-Tetrahydrocarbazole Based Fluorophores: From Inception to Implementation. J Fluoresc 2022; 32:2023-2052. [PMID: 35829843 DOI: 10.1007/s10895-022-03004-2] [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: 05/25/2022] [Accepted: 07/01/2022] [Indexed: 10/17/2022]
Abstract
Carbazole is a unique template associated with several biological activities. It is due to the diverse and versatile biological properties of carbazole derivatives that they are of immense interest to the research community. 1-keto-1,2,3,4-tetrahydrocarbazoles are important synthetic intermediates to obtain carbazole derivatives. Several members of this family emit fluorescence on photoexcitation. In the context of biochemical and biophysical research, designing and characterising small molecule environment sensitive fluorophores is extremely significant. This article aims to be a state of the art review with synthetic and photophysical details of a variety of fluorophores based on 1-keto-1,2,3,4-tetrahydrocarbazole skeleton.
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23
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Capacitive Water-Cut Meter with Robust Near-Linear Transfer Function. COMPUTATION 2022. [DOI: 10.3390/computation10070115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The water content in fuel–water emulsions can vary from 10% to 30%, and is under control during the process of emulsification. The main task of this study was to obtain near-linear static function for a water-cut meter with capacitive sensors, and to provide it with effective type-uncertainty compensation during the process of water–fuel emulsion moisture control. To fulfill the capacitive measurements, two capacitive sensors in the measuring channel and two capacitive sensors in the reference channel were used. The method of least squares and general linear regression instruments were used to obtain robust and near-linear transfer function of the capacitive water-cut meter. The prototype product of the water-cut meter was developed with the purpose of fulfilling multiple moisture measurements and checking the workability of the new transfer function. Values of moisture content for the new transfer function and the closest analog were compared with the help of dispersion analysis. The new transfer function provided minimal dispersions of repeatability and adequacy, and minimal F-test values, proving its better capability for type-uncertainty compensation and better adequacy for the nominal linear transfer function of the water-cut meter.
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24
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Doan LC, Dahanayake JN, Mitchell-Koch KR, Singh AK, Vinh NQ. Probing Adaptation of Hydration and Protein Dynamics to Temperature. ACS OMEGA 2022; 7:22020-22031. [PMID: 35785325 PMCID: PMC9245114 DOI: 10.1021/acsomega.2c02843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Protein dynamics is strongly influenced by the surrounding environment and physiological conditions. Here we employ broadband megahertz-to-terahertz spectroscopy to explore the dynamics of water and myoglobin protein on an extended time scale from femto- to nanosecond. The dielectric spectra reveal several relaxations corresponding to the orientational polarization mechanism, including the dynamics of loosely bound, tightly bound, and bulk water, as well as collective vibrational modes of protein in an aqueous environment. The dynamics of loosely bound and bulk water follow non-Arrhenius behavior; however, the dynamics of water molecules in the tightly bound layer obeys the Arrhenius-type relation. Combining molecular simulations and effective-medium approximation, we have determined the number of water molecules in the tightly bound hydration layer and studied the dynamics of protein as a function of temperature. The results provide the important impact of water on the biochemical functions of proteins.
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Affiliation(s)
- Luan C. Doan
- Department
of Physics and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia 24061, United States
- Department
of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Jayangika N. Dahanayake
- Department
of Chemistry, Faculty of Science, University
of Kelaniya, Kelaniya 11600, Sri Lanka
| | | | - Abhishek K. Singh
- Department
of Physics and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Nguyen Q. Vinh
- Department
of Physics and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia 24061, United States
- Department
of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
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25
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Hu K, Matsuura H, Shirakashi R. Stochastic Analysis of Molecular Dynamics Reveals the Rotation Dynamics Distribution of Water around Lysozyme. J Phys Chem B 2022; 126:4520-4530. [PMID: 35675630 DOI: 10.1021/acs.jpcb.2c00970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Water dynamics is essential to biochemical processes by mediating all such reactions, including biomolecular degeneration in solutions. To disentangle the molecular-scale distribution of water dynamics around a solute biomolecule, we investigated here the rotational dynamics of water around lysozyme by combining molecular dynamics (MD) simulations and broadband dielectric spectroscopy (BDS). A statistical analysis using the relaxation times and trajectories of every single water molecule was proposed, and the two-dimensional probability distribution of water at a distance from the lysozyme surface with a rotational relaxation time was given. For the observed lysozyme solutions of 34-284 mg/mL, we discovered that the dielectric relaxation time obtained from this distribution agrees well with the measured γ relaxation time, which suggests that rotational self-correlation of water molecules underlies the gigahertz domain of the dielectric spectra. Regardless of protein concentration, water rotational relaxation time versus the distance from the lysozyme surface revealed that the water rotation is severely retarded within 3 Å from the lysozyme surface and is nearly comparable to pure water when farther than 10 Å. The dimension of the first hydration layer was subsequently identified in terms of the relationship between the acceleration of water rotation and the distance from the protein surface.
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Affiliation(s)
- Kang Hu
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro City, Tokyo 153-8505, Japan.,Department of Mechanical Engineering, The University of Tokyo, 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroaki Matsuura
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro City, Tokyo 153-8505, Japan.,Research Fellow of the Japan Society for the Promotion of Science, Chiyoda-ku, Tokyo 102-0083, Japan
| | - Ryo Shirakashi
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro City, Tokyo 153-8505, Japan
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26
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Rahman M, Islam KR, Islam MR, Islam MJ, Kaysir MR, Akter M, Rahman MA, Alam SMM. A Critical Review on the Sensing, Control, and Manipulation of Single Molecules on Optofluidic Devices. MICROMACHINES 2022; 13:968. [PMID: 35744582 PMCID: PMC9229244 DOI: 10.3390/mi13060968] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 05/19/2022] [Accepted: 05/23/2022] [Indexed: 02/06/2023]
Abstract
Single-molecule techniques have shifted the paradigm of biological measurements from ensemble measurements to probing individual molecules and propelled a rapid revolution in related fields. Compared to ensemble measurements of biomolecules, single-molecule techniques provide a breadth of information with a high spatial and temporal resolution at the molecular level. Usually, optical and electrical methods are two commonly employed methods for probing single molecules, and some platforms even offer the integration of these two methods such as optofluidics. The recent spark in technological advancement and the tremendous leap in fabrication techniques, microfluidics, and integrated optofluidics are paving the way toward low cost, chip-scale, portable, and point-of-care diagnostic and single-molecule analysis tools. This review provides the fundamentals and overview of commonly employed single-molecule methods including optical methods, electrical methods, force-based methods, combinatorial integrated methods, etc. In most single-molecule experiments, the ability to manipulate and exercise precise control over individual molecules plays a vital role, which sometimes defines the capabilities and limits of the operation. This review discusses different manipulation techniques including sorting and trapping individual particles. An insight into the control of single molecules is provided that mainly discusses the recent development of electrical control over single molecules. Overall, this review is designed to provide the fundamentals and recent advancements in different single-molecule techniques and their applications, with a special focus on the detection, manipulation, and control of single molecules on chip-scale devices.
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Affiliation(s)
- Mahmudur Rahman
- Department of Electrical and Electronic Engineering, Dhaka University of Engineering & Technology, Gazipur 1707, Bangladesh; (M.R.); (K.R.I.); (M.R.I.); (M.A.); (M.A.R.)
| | - Kazi Rafiqul Islam
- Department of Electrical and Electronic Engineering, Dhaka University of Engineering & Technology, Gazipur 1707, Bangladesh; (M.R.); (K.R.I.); (M.R.I.); (M.A.); (M.A.R.)
| | - Md. Rashedul Islam
- Department of Electrical and Electronic Engineering, Dhaka University of Engineering & Technology, Gazipur 1707, Bangladesh; (M.R.); (K.R.I.); (M.R.I.); (M.A.); (M.A.R.)
| | - Md. Jahirul Islam
- Department of Electrical and Electronic Engineering, Khulna University of Engineering & Technology, Khulna 9203, Bangladesh;
| | - Md. Rejvi Kaysir
- Department of Electrical and Computer Engineering, University of Waterloo, 200 University Ave. W, Waterloo, ON N2L 3G1, Canada;
- Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Ave. W, Waterloo, ON N2L 3G1, Canada
| | - Masuma Akter
- Department of Electrical and Electronic Engineering, Dhaka University of Engineering & Technology, Gazipur 1707, Bangladesh; (M.R.); (K.R.I.); (M.R.I.); (M.A.); (M.A.R.)
| | - Md. Arifur Rahman
- Department of Electrical and Electronic Engineering, Dhaka University of Engineering & Technology, Gazipur 1707, Bangladesh; (M.R.); (K.R.I.); (M.R.I.); (M.A.); (M.A.R.)
| | - S. M. Mahfuz Alam
- Department of Electrical and Electronic Engineering, Dhaka University of Engineering & Technology, Gazipur 1707, Bangladesh; (M.R.); (K.R.I.); (M.R.I.); (M.A.); (M.A.R.)
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27
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Bhattacharyya K. Of Molecules, Time, and Space Resolution: An Autobiography of Kankan Bhattacharyya. J Phys Chem B 2022; 126:3464-3469. [PMID: 35586922 DOI: 10.1021/acs.jpcb.2c02492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kankan Bhattacharyya
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal 462066, Madhya Pradesh, India
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28
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Adhyapak P, Dong W, Dasgupta S, Dutta A, Duan M, Kapoor S. Lipid Clustering in Mycobacterial Cell Envelope Layers Governs Spatially Resolved Solvation Dynamics. Chem Asian J 2022; 17:e202200146. [PMID: 35419975 DOI: 10.1002/asia.202200146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/30/2022] [Indexed: 11/06/2022]
Abstract
The mycobacterial cell envelope acts as a multilayered barrier to drugs. However, the role of lipid composition in the properties of different mycobacterial membranes, otherwise dictating their interactions with drugs, is poorly understood. In this study, we found that hydration states, solvation relaxation kinetics, rotational lipid mobility, and lateral lipid diffusion differed between inner and outer mycobacterial membranes. Molecular modeling showed that lipid clustering patterns governed membrane dynamics in the different layers of the cell envelope. By regulating membrane properties, lipid composition and structure modulated water abundance and interactions with lipid head groups. These findings can help deepen our understanding of the physical chemistry underlying membrane structure and function, as well as the interaction of mycobacterial membranes with drugs and host membranes.
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Affiliation(s)
- Pranav Adhyapak
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Wanqian Dong
- Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, P. R. China
| | - Souradip Dasgupta
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Anindya Dutta
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Mojie Duan
- Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, P. R. China
| | - Shobhna Kapoor
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India.,Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, 739-8528, Japan
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29
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Xie L, Ding Y, Li D, Zhang C, Wu Y, Sun L, Liu M, Qiu X, Xu W. Local Chiral Inversion of Thymine Dimers by Manipulating Single Water Molecules. J Am Chem Soc 2022; 144:5023-5028. [PMID: 35285637 DOI: 10.1021/jacs.1c13344] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Water, as one of the most important and indispensable small molecules in vivo, plays a crucial role in driving biological self-assembly processes. Real-space detection and identification of water-induced organic structures and further capture of dynamic dehydration processes are important yet challenging, which would help to reveal the cooperation and competition mechanisms among water-involved noncovalent interactions. Herein, introduction of water molecules onto the self-assembled thymine (T) structures under ultrahigh vacuum (UHV) conditions results in the hydration of hydrogen-bonded T dimers forming a well-ordered water-involved T structure. Reversibly, a local dehydration process is achieved by in situ scanning tunneling microscopy (STM) manipulation on single water molecules, where the adjacent T dimers connected with water molecules undergo a local chiral inversion process with the hydrogen-bonding configuration preserved. Such a strategy enables real-space identification and detection of the interactions between water and organic molecules, which may also shed light on the understanding of biologically relevant self-assembly processes driven by water.
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Affiliation(s)
- Lei Xie
- Interdisciplinary Materials Research Center, College of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China.,Shanghai Synchrotron Radiation Facility, Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, People's Republic of China
| | - Yuanqi Ding
- Interdisciplinary Materials Research Center, College of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
| | - Donglin Li
- Interdisciplinary Materials Research Center, College of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
| | - Chi Zhang
- Interdisciplinary Materials Research Center, College of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
| | - Yangfan Wu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China.,School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Luye Sun
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China.,University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Mengxi Liu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
| | - Xiaohui Qiu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China.,University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Wei Xu
- Interdisciplinary Materials Research Center, College of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
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30
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Samanta A, Ghosh SK. Dynamics in condensed phase for systems involving phase functions obeying Gaussian statistics. J INDIAN CHEM SOC 2022. [DOI: 10.1016/j.jics.2021.100290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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31
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Hande VR, Chakrabarty S. How Far Is "Bulk Water" from Interfaces? Depends on the Nature of the Surface and What We Measure. J Phys Chem B 2022; 126:1125-1135. [PMID: 35104127 DOI: 10.1021/acs.jpcb.1c08603] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using systematic molecular dynamics (MD) simulations, we revisit the question: At what distance from an interface do the properties of "bulk water" get recovered? We have considered three different kinds of interfaces: nonpolar (hydrophobic; isooctane-water interface), charged (negative; AOT bilayer), and polar (zwitterionic; POPC bilayer). In order to interrogate the extent of perturbation of the interfacial water molecules as a function of the distance from the interface, we utilize a diverse range of structural and dynamical parameters. To capture the structural perturbations, we look into local density (translational order), local tetrahedral order parameter, and dipolar orientation of the water molecules. We also explore the anisotropic diffusion of the water molecules in the direction perpendicular to the interface as well as the planar diffusion parallel to the interface in a distance dependent manner. In addition, the orientational time correlation functions have been computed to understand the extent of slowdown in the rotational dynamics. As expected, the electrostatic field emanating from the charged AOT interface seems to have the highest long-range effect on the orientational order and dynamics of the water molecules, whereas specific interactions like hydrogen bonding and electrostatic interaction lead to significant trapping and kinetic slowdown for both AOT and POPC (zwitterionic) very close to the interface. Our analysis highlights that not only the length-scale of perturbation depends on the nature of the interfaces and specific interactions but also the type of water property that we measure/calculate. Different water properties seem to have widely different length-scale of perturbation. Orientational order parameters seem to be perturbed to a much longer length-scale as compared to translational order parameters. The global orientational order of water can be perturbed even up to ∼4-5 nm near the negatively charged AOT surface in the absence of any extra electrolyte. This observation has significant implication toward the interpretation of experimental measurements as well since different spectroscopic techniques would probe different parameters or water properties with possible mutual disagreement and inconsistency between different types of measurements. Thus, our study provides a broader and unifying perspective toward the aspect of "context dependent" structural and dynamical perturbation of "interfacial water".
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Affiliation(s)
- Vrushali R Hande
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Suman Chakrabarty
- Department of Chemical, Biological & Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata 700106, India
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Das B, Chandra A. Effects of Stearyl Alcohol Monolayer on the Structure, Dynamics and Vibrational Sum Frequency Generation Spectroscopy of Interfacial Water. Phys Chem Chem Phys 2022; 24:7374-7386. [DOI: 10.1039/d1cp04944e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The structure, dynamics and vibrational spectroscopy of water surface covered by a monolayer of stearyl alcohol (STA) are investigated by means of molecular dynamics simulations and vibrational sum frequency generation...
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Nandi S, Pyne A, Layek S, Arora C, Sarkar N. The Dietary Nutrient Trimethylamine N-Oxide Affects the Phospholipid Vesicle Membrane: Probable Route to Adverse Intake. J Phys Chem Lett 2021; 12:12411-12418. [PMID: 34939822 DOI: 10.1021/acs.jpclett.1c03201] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Trimethylamine N-oxide (TMAO), a choline-containing dietary supplement obtained from red meat, egg, and other animal resources, on excess accumulation is known to cause cardiovascular diseases (CVDs) like atherosclerosis. To understand the molecular mechanism of the pathogenesis of TMAO-induced CVDs, we have set up 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) membrane in water that mimicked the endothelial cell membrane-blood interface of the artery wall and investigated the effect of an elevated concentration of TMAO on the membrane. We found that TMAO exerts an "action at a distance" mechanism through electrostatic force of attraction that significantly alters various properties of the membrane, like hydrophobicity, lateral organization, and interfacial water dynamics, which elevates the rigidity of the membrane. Such an effect was found to be further amplified in the presence of known causes of CVDs, i.e., high content of cholesterol (Chol). Therefore, TMAO-induced membrane rigidity may restrict the intrinsic elasticity of an artery membrane, expected to be introducing "hardening of the arteries", which makes the membrane atherosclerotic.
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Affiliation(s)
- Sourav Nandi
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, WB 721302, India
| | - Arghajit Pyne
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, WB 721302, India
| | - Souvik Layek
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, WB 721302, India
| | - Chirag Arora
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, WB 721302, India
| | - Nilmoni Sarkar
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, WB 721302, India
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Relationships between Molecular Structure of Carbohydrates and Their Dynamic Hydration Shells Revealed by Terahertz Time-Domain Spectroscopy. Int J Mol Sci 2021; 22:ijms222111969. [PMID: 34769399 PMCID: PMC8584907 DOI: 10.3390/ijms222111969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/26/2021] [Accepted: 11/03/2021] [Indexed: 11/17/2022] Open
Abstract
Despite more than a century of research on the hydration of biomolecules, the hydration of carbohydrates is insufficiently studied. An approach to studying dynamic hydration shells of carbohydrates in aqueous solutions based on terahertz time-domain spectroscopy assay is developed in the current work. Monosaccharides (glucose, galactose, galacturonic acid) and polysaccharides (dextran, amylopectin, polygalacturonic acid) solutions were studied. The contribution of the dissolved carbohydrates was subtracted from the measured dielectric permittivities of aqueous solutions based on the corresponding effective medium models. The obtained dielectric permittivities of the water phase were used to calculate the parameters describing intermolecular relaxation and oscillatory processes in water. It is established that all of the analyzed carbohydrates lead to the increase of the binding degree of water. Hydration shells of monosaccharides are characterized by elevated numbers of hydrogen bonds and their mean energies compared to undisturbed water, as well as by elevated numbers and the lifetime of free water molecules. The axial orientation of the OH(4) group of sugar facilitates a wider distribution of hydrogen bond energies in hydration shells compared to equatorial orientation. The presence of the carboxylic group affects water structure significantly. The hydration of polysaccharides is less apparent than that of monosaccharides, and it depends on the type of glycosidic bonds.
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35
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Mukherjee S, Acharya S, Mondal S, Banerjee P, Bagchi B. Structural Stability of Insulin Oligomers and Protein Association-Dissociation Processes: Free Energy Landscape and Universal Role of Water. J Phys Chem B 2021; 125:11793-11811. [PMID: 34674526 DOI: 10.1021/acs.jpcb.1c05811] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Association and dissociation of proteins are important biochemical events. In this Feature Article, we analyze the available studies of these processes for insulin oligomers in aqueous solution. We focus on the solvation of the insulin monomer in water, stability and dissociation of its dimer, and structural integrity of the hexamer. The intricate role of water in solvation of the dimer- and hexamer-forming surfaces, in long-range interactions between the monomers and the stability of the oligomers, is discussed. Ten water molecules inside the central cavity stabilize the structure of the insulin hexamer. We discuss how different order parameters can be used to understand the dissociation of the insulin dimer. The calculation of the rate using a recently computed multidimensional free energy provides considerable insight into the interplay between protein and water dynamics.
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Affiliation(s)
- Saumyak Mukherjee
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Subhajit Acharya
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Sayantan Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Puja Banerjee
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Biman Bagchi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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36
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Paul R, Mitra A, Paul S. A computational approach on the stereoselective binding of peptides from aqueous medium with endo-functionalized molecular tubes. Phys Chem Chem Phys 2021; 23:22703-22717. [PMID: 34605508 DOI: 10.1039/d1cp02288a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The need to obtain enantiomerically pure isomers of amino acids and peptides is often realized in the field of biology and in the pharmaceutical industry. Research is underway to devise simple methods for the chiral resolution of amino acids from their racemic mixtures. Inspired by this objective, in our present work, we have computationally shown the possibility of chiral separation of the enantiomeric pairs of two model peptides, namely, (D,L)-aspargine and (D,L)-phenylalanine, in the presence of water. For this purpose, we have used two synthetic supramolecular receptors named host-1a and host-1b, respectively. Molecular dynamics simulations and quantum chemical methods are employed to analyze the structural features and the energy aspects involved in the separation process. The information obtained at the molecular level helps us gain better insights into the key interactions that operate to produce such enantioselectivity. We have also investigated the dynamics and changes in the water structure in the vicinity of the host molecules, both in the presence and absence of the model peptides. The D- and L-isomers of the same peptide undergo complexation with a particular host molecule registering a difference of more than 1.5 kcal mol-1 (obtained from PMF and MM-PBSA analyses) in their respective energies. This indicates that the chiral separation of the peptides with the help of these endo-fuctionalized molecular tube receptors may be energetically feasible. The connection between the peptide stereochemistry and its interaction with the endo-functionalized hosts would be instrumental in designing novel segregation techniques that can be further extended to separate larger model peptides or proteins.
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Affiliation(s)
- Rabindranath Paul
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India.
| | - Aritra Mitra
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India.
| | - Sandip Paul
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India.
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Miyazaki M, Kamiya T, Wohlgemuth M, Chatterjee K, Mitrić R, Dopfer O, Fujii M. Real-time observation of photoionization-induced water migration dynamics in 4-methylformanilide-water by picosecond time-resolved infrared spectroscopy and ab initio molecular dynamics simulations. Phys Chem Chem Phys 2021; 24:73-85. [PMID: 34633007 DOI: 10.1039/d1cp03327a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A novel time-resolved pump-probe spectroscopic approach that enables to keep high resolution in both the time and energy domain, nanosecond excitation-picosecond ionization-picosecond infrared probe (ns-ps-ps TRIR) spectroscopy, has been applied to the trans-4-methylformanilide-water (4MetFA-W) cluster. Water migration dynamics from the CO to the NH binding site in a peptide linkage triggered by photoionization of 4MetFA-W is directly monitored by the ps time evolution of IR spectra, and the presence of an intermediate state is revealed. The time evolution is analyzed by rate equations based on a four-state model of the migration dynamics. Time constants for the initial to the intermediate and hot product and to the final product are obtained. The acceleration of the dynamics by methyl substitution and the strong contribution of intracluster vibrational energy redistribution in the termination of the solvation dynamics is suggested. This picture is well confirmed by the ab initio on-the-fly molecular dynamics simulations. Vibrational assignments of 4MetFA and 4MetFA-W in the neutral (S0 and S1) and ionic (D0) electronic states measured by ns IR dip and electron-impact IR photodissociation spectroscopy are also discussed prior to the results of time-resolved spectroscopy.
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Affiliation(s)
- Mitsuhiko Miyazaki
- Natural Science Division, Faculty of Core Research, Ochanomizu University, 2-1-1 Ohtsuka, Bunkyo-ku, Tokyo 112-8610, Japan. .,Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Tairiku Kamiya
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Matthias Wohlgemuth
- Institut für Physikalische und Theoretische Chemie, Julius-Maximilians-Universität Würzburg, 97074 Würzburg, Germany.
| | - Kuntal Chatterjee
- Institut für Optik und Atomare Physik, Technische Universität Berlin, 10623 Berlin, Germany.
| | - Roland Mitrić
- Institut für Physikalische und Theoretische Chemie, Julius-Maximilians-Universität Würzburg, 97074 Würzburg, Germany.
| | - Otto Dopfer
- Institut für Optik und Atomare Physik, Technische Universität Berlin, 10623 Berlin, Germany. .,World Research Hub Initiatives, Institute of Innovative Research, Tokyo Institute of Technology, 4259-R1-15, Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan.
| | - Masaaki Fujii
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan.,World Research Hub Initiatives, Institute of Innovative Research, Tokyo Institute of Technology, 4259-R1-15, Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan.
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38
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Roget SA, Piskulich ZA, Thompson WH, Fayer MD. Identical Water Dynamics in Acrylamide Hydrogels, Polymers, and Monomers in Solution: Ultrafast IR Spectroscopy and Molecular Dynamics Simulations. J Am Chem Soc 2021; 143:14855-14868. [PMID: 34491037 DOI: 10.1021/jacs.1c07151] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The dynamics and structure of water in polyacrylamide hydrogels (PAAm-HG), polyacrylamide, and acrylamide solutions are investigated using ultrafast infrared experiments on the OD stretch of dilute HOD/H2O and molecular dynamics simulations. The amide moiety of the monomer/polymers interacts strongly with water through hydrogen bonding (H-bonding). The FT-IR spectra of the three systems indicate that the range of H-bond strengths is relatively unchanged from bulk water. Vibrational population relaxation measurements show that the amide/water H-bonds are somewhat weaker but fall within the range of water/water H-bond strengths. A previous study of water dynamics in PAAm-HG suggested that the slowing observed was due to increasing confinement with concentration. Here, for the same concentrations of the amide moiety, the experimental results demonstrate that the reorientational dynamics (infrared pump-probe experiments) and structural dynamics (two-dimensional infrared spectroscopy) are identical in the three acrylamide systems studied. Molecular dynamics simulations of the water orientational relaxation in aqueous solutions of the acrylamide monomer, trimer, and pentamer are in good agreement with the experimental results and are essentially chain length independent. The simulations show that there is a slower, low-amplitude (<7%) decay component not accessible by the experiments. The simulations examine the dynamics and structure of water H-bonded to acrylamide, in the first solvent shell, and beyond for acrylamide monomers and short chains. The experiments and simulations show that the slowing of water dynamics in PAAm-HG is not caused by confinement in the polymer network but rather by interactions with individual acrylamide moieties.
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Affiliation(s)
- Sean A Roget
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Zeke A Piskulich
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Ward H Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Michael D Fayer
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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39
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Paul R, Paul S. Exploration on the drug solubility enhancement in aqueous medium with the help of endo-functionalized molecular tubes: a computational approach. Phys Chem Chem Phys 2021; 23:18999-19010. [PMID: 34612438 DOI: 10.1039/d1cp01187a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
One major problem in the pharmaceutical industry is the aqueous solubility of newly developed orally administered drug candidates. More than 50% of newly developed drug molecules suffer from low aqueous solubility. The therapeutic effects of drug molecules are majorly dependent on the bioavailability and, in essence, on the solubility of the used drug molecules. Thus, enhancement of drug solubility of sparingly soluble drug molecules is a need of modern times. Considering the high importance of drug solubility, we have computationally shown the enhancement of drug solubility for seven class II (poorly water-soluble) drug molecules in a water medium. The uses of supramolecular macrocycles have immense importance in the same field. Thus, we have used two synthetic supramolecular receptors named host-1a and host-1b to enhance the water solubility of fluorouracil, albendazole, camptothecin, clopidogrel, indomethacin, melphalan, and tolfenamic acid drug molecules. Biomedical engagements of a supramolecular receptor commence with the formation of stable host-drug complexes. These complexations enhance the water solubility of drug molecules and sustain the release rate and bioavailability of drug molecules. Thus, in this work, we focus on the formation of stable host-drug complexes in water medium. Molecular dynamics simulation is applied to analyze the structural features and the energetics involved in the host-drug complexation process. The information obtained at the atomistic level helps us gain better insights into the key interactions that operate to produce such highly stable complexes. Thus, we can propose that these two supramolecular receptors may be used as drug solubilizing agents, and patients will benefit from this theragnostic application shortly.
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Affiliation(s)
- Rabindranath Paul
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India.
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40
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Nandi S, Ghosh B, Ghosh M, Layek S, Nandi PK, Sarkar N. Phenylalanine Interacts with Oleic Acid-Based Vesicle Membrane. Understanding the Molecular Role of Fibril-Vesicle Interaction under the Context of Phenylketonuria. J Phys Chem B 2021; 125:9776-9793. [PMID: 34420302 DOI: 10.1021/acs.jpcb.1c05592] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the present contribution, on the basis of a spectroscopic and microscopic investigation, the characterization and photophysics of various assemblies of oleic acid/oleate solution at three pH values, namely, 8.28, 9.72, and 11.77, were explored. The variation in the dynamic response of aqua molecules in and around the assemblies has been interrogated by a picoseconds solvation dynamics experiment using a time-correlated single-photon counting setup employing coumarin-153 as a probe. On the one hand, the time-resolved fluorescence anisotropy measurement along with the fluorescence correlation spectroscopy experiment was executed to extract information regarding the comparison of the extent of the internal restricted confinement of these assemblies. On the other hand, an effort to investigate the cross-interaction between the self-assembled architectures of l-phenylalanine (l-Phe), responsible for phenylketonuria (PKU) disorder, and the oleic acid at the vesicle-forming pH established that the l-Phe fibrillar morphologies strongly alter the dynamic properties of the vesicle membrane formed by the oleic acid. Specifically, the interaction of the l-Phe assemblies with the oleic acid vesicle membrane is found to introduce the flexibility of the vesicle membrane and alter the hydration properties of the membrane. To track the fibril-induced alterations of the oleic acid vesicle properties, various spectroscopic and microscopic investigations were performed. The mutual reconciliation of the experimental outputs, therefore, portrays the state of the art, which accounts for the fibril-induced alterations of the properties of the oleic acid vesicle membrane, the mimicking setup of the cellular membrane, thereby informing us that alterations of such a property of the membrane should be taken into active consideration during the rational development of therapeutic modulators against disorders like PKU.
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Affiliation(s)
- Sourav Nandi
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
| | - Biswajoy Ghosh
- School of Medical Science and Technology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
| | - Meghna Ghosh
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
| | - Souvik Layek
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
| | - Pratyush Kiran Nandi
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
| | - Nilmoni Sarkar
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
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41
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Paul R, Paul S. Translocation of Endo-Functionalized Molecular Tubes across Different Lipid Bilayers: Atomistic Molecular Dynamics Simulation Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:10376-10387. [PMID: 34415773 DOI: 10.1021/acs.langmuir.1c01594] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Various artificial receptors, such as calixarenes, cyclodextrins, cucurbit[n]urils, and their acyclic compounds, pliiar[n]arenes, deep cavitands, and molecular tweezers, can permeate the lipid membranes and they are used as drug carriers to improve the drug solubility, stability, and bioavailability. Inspired by these, we have employed atomistic molecular dynamics simulation to examine the effects of endo-functionalized molecular tubes or naphthotubes (host-1a and host-1b) on seven different types of model lipid bilayers and the permeation properties of these receptors through these model lipid bilayers. Lipid types include six model lipid bilayers (POPC, POPE, DOPC, POPG, DPPE, POPE/POPG) and one realistic membrane (Yeast). We observe that these receptors are spontaneously translocated toward these model lipid bilayer head regions and do not proceed further into these lipid bilayer tail regions (reside at the interface between lipid head and lipid tail region), except for the DPPE-containing systems. In the DPPE model lipid bilayer-containing systems (1a-dppe and 1b-dppe), receptor molecules are only adsorbed on the bilayer surface and reside at the interface between lipid head and water. This finding is also supported by the biased free-energy profiles of these translocation processes. Passive transport of these receptors may be possible through these model lipid bilayers (due to low barrier height), except for DPPE bilayer-containing systems (that have a very high energy barrier at the center). The results from these simulations provide insight into the biocompatibility of host-1a or host-1b in microscopic detail. Based on this work, more research is needed to fully comprehend the role of these synthesized receptors as a prospective drug carrier.
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Affiliation(s)
- Rabindranath Paul
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India
| | - Sandip Paul
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam 781039, India
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42
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Latypova L, Puzenko A, Poluektov Y, Anashkina A, Petrushanko I, Bogdanova A, Feldman Y. Hydration of methemoglobin studied by in silico modeling and dielectric spectroscopy. J Chem Phys 2021; 155:015101. [PMID: 34241395 DOI: 10.1063/5.0054697] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The hemoglobin concentration of 35 g/dl of human red blood cells is close to the solubility threshold. Using microwave dielectric spectroscopy, we have assessed the amount of water associated with hydration shells of methemoglobin as a function of its concentration in the presence or absence of ions. We estimated water-hemoglobin interactions to interpret the obtained data. Within the concentration range of 5-10 g/dl of methemoglobin, ions play an important role in defining the free-to-bound water ratio competing with hemoglobin to recruit water molecules for the hydration shell. At higher concentrations, hemoglobin is a major contributor to the recruitment of water to its hydration shell. Furthermore, the amount of bound water does not change as the hemoglobin concentration is increased from 15 to 30 g/dl, remaining at the level of ∼20% of the total intracellular water pool. The theoretical evaluation of the ratio of free and bound water for the hemoglobin concentration in the absence of ions corresponds with the experimental results and shows that the methemoglobin molecule binds about 1400 water molecules. These observations suggest that within the concentration range close to the physiological one, hemoglobin molecules are so close to each other that their hydration shells interact. In this case, the orientation of the hemoglobin molecules is most likely not stochastic, but rather supports partial neutralization of positive and negative charges at the protein surface. Furthermore, deformation of the red blood cell shape results in the rearrangement of these structures.
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Affiliation(s)
- Larisa Latypova
- Department of Applied Physics, The Hebrew University of Jerusalem, Givat Ram 91904, Israel
| | - Alexander Puzenko
- Department of Applied Physics, The Hebrew University of Jerusalem, Givat Ram 91904, Israel
| | - Yuri Poluektov
- Engelhart Institute of Molecular Biology, Russian Academy of Science, Vavilov St. 32, 119991 Moscow, Russia
| | - Anastasia Anashkina
- Engelhart Institute of Molecular Biology, Russian Academy of Science, Vavilov St. 32, 119991 Moscow, Russia
| | - Irina Petrushanko
- Engelhart Institute of Molecular Biology, Russian Academy of Science, Vavilov St. 32, 119991 Moscow, Russia
| | - Anna Bogdanova
- Red Blood Cell Research Group, Institute of Veterinary Physiology, University of Zürich, Winterthurerstrasse 260, CH-8057 Zürich, Switzerland
| | - Yuri Feldman
- Department of Applied Physics, The Hebrew University of Jerusalem, Givat Ram 91904, Israel
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43
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Cho Y, Christoff-Tempesta T, Kaser SJ, Ortony JH. Dynamics in supramolecular nanomaterials. SOFT MATTER 2021; 17:5850-5863. [PMID: 34114584 DOI: 10.1039/d1sm00047k] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Self-assembly of amphiphilic small molecules in water leads to nanostructures with customizable structure-property relationships arising from their tunable chemistries. Characterization of these assemblies is generally limited to their static structures -e.g. their geometries and dimensions - but the implementation of tools that provide a deeper understanding of molecular motions has recently emerged. Here, we summarize recent reports showcasing dynamics characterization tools and their application to small molecule assemblies, and we go on to highlight supramolecular systems whose properties are substantially affected by their conformational, exchange, and water dynamics. This review illustrates the importance of considering dynamics in rational amphiphile design.
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Affiliation(s)
- Yukio Cho
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Ty Christoff-Tempesta
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Samuel J Kaser
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Julia H Ortony
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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44
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Sathyamurthy N. Atoms and molecules confined inside C60. PROCEEDINGS OF THE INDIAN NATIONAL SCIENCE ACADEMY 2021. [DOI: 10.1007/s43538-021-00003-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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45
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Oka Y, Miura T, Ikoma T. Photogenerated Radical Pair between Flavin and a Tryptophan-Containing Transmembrane-Type Peptide in a Large Unilamellar Vesicle. J Phys Chem B 2021; 125:4057-4066. [PMID: 33858138 DOI: 10.1021/acs.jpcb.1c01231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electron-transfer (ET) reactions in biological systems, such as those with magnetic sensors based on flavoproteins and electron transport at biomembrane interfaces, are interesting and important issues that require understanding. As a model system of flavoproteins in biomimetic environments, we report the dynamics of the radical pair generated by photoinduced ET between riboflavin tetrabutylate (RFTB) and tryptophan (Trp) residues in a transmembrane-type polypeptide, both of which are distributed in a large unilamellar vesicle of 1,2-dimyristoyl-sn-glycero-3-phosphocholine. The Trp residues locate near the hydrophilic membrane interface, as confirmed by a dual-fluorescence quenching assay. The fluorescence and transient absorption upon photoexcitation of RFTB indicate that ET from both the singlet and triplet excited states occurs at the hydrophilic interface, whereas the RFTB in the hydrophobic region does not contribute to ET. The ET efficiency and the magnetic field effect (MFE) on the RFTB anion increase significantly above the gel-to-liquid crystal phase transition temperature due to a decrease in microviscosity. The MFE analysis indicates that the radical pair generated from the triplet ET channel exhibits a long lifetime as those in micellar systems due to the strong cage effect of the vesicle.
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Affiliation(s)
- Yoshimi Oka
- Frontier Research Core for Life Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Tomoaki Miura
- Department of Chemistry, Faculty of Science, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 950-2181, Japan
| | - Tadaaki Ikoma
- Department of Chemistry, Faculty of Science, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 950-2181, Japan
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Kundu S, Chowdhury A, Nandi S, Bhattacharyya K, Patra A. Deciphering the evolution of supramolecular nanofibers in solution and solid-state: a combined microscopic and spectroscopic approach. Chem Sci 2021; 12:5874-5882. [PMID: 34168812 PMCID: PMC8179674 DOI: 10.1039/d0sc07050e] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 03/17/2021] [Indexed: 12/21/2022] Open
Abstract
Supramolecular self-assembly of small organic molecules has emerged as a powerful tool to construct well-defined micro- and nanoarchitecture through fine-tuning a range of intermolecular interactions. The size, shape, and optical properties of these nanostructures largely depend on the specific assembly of the molecular building units, temperature and polarity of the medium, and external stimuli. The engineering of supramolecular self-assembled nanostructures with morphology-dependent tunable emission is in high demand due to the promising scope in nanodevices and molecular machines. However, probing the evolution of molecular aggregates from the solution and directing the self-assembly process in a pre-defined fashion are challenging. In the present study, we have deciphered the sequential evolution of supramolecular nanofibers from solution to spherical and oblong-shaped nanoparticles through the variation of solvent polarity, tuning the hydrophobic-hydrophilic interactions. An intriguing case of molecular self-assembly has been elucidated employing a newly designed π-conjugated thiophene derivative (TPAn) through a combination of steady-state absorption, emission measurements, fluorescence correlation spectroscopy (FCS), and electron microscopy. The FCS analysis and microscopy results revealed that the small-sized nanofibers in the dispersion further agglomerated upon solvent evaporation, resulting in a network of nanofibers. Stimuli-responsive reversible interconversion between a network of nanofibers and spherical nanoaggregates was probed both in dispersion and solvent-evaporated state. The evolution of organic nanofibers and a subtle control over the self-assembly process demonstrated in the current investigation provide a general paradigm to correlate the size, shape, and emission properties of fluorescent molecular aggregates in complex heterogeneous media, including a human cell.
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Affiliation(s)
- Subhankar Kundu
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal By-Pass Road, Bhauri Bhopal 462066 Madhya Pradesh India
| | - Arkaprava Chowdhury
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal By-Pass Road, Bhauri Bhopal 462066 Madhya Pradesh India
| | - Somen Nandi
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal By-Pass Road, Bhauri Bhopal 462066 Madhya Pradesh India
| | - Kankan Bhattacharyya
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal By-Pass Road, Bhauri Bhopal 462066 Madhya Pradesh India
| | - Abhijit Patra
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal By-Pass Road, Bhauri Bhopal 462066 Madhya Pradesh India
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Fujii K, Nakano H, Sato H, Kimura Y. Experimental observation of the unique solvation process along multiple solvation coordinates of photodissociated products. Phys Chem Chem Phys 2021; 23:4569-4579. [PMID: 33616585 DOI: 10.1039/d0cp06588a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chemical reaction dynamics in solution are closely related to solvation dynamics, and understanding solvent responses remains a crucial issue in chemistry and chemical biology. In this study, we experimentally and computationally investigated the solvation dynamics along different solvation coordinates of the same molecule: the electronically excited state and ground state of the p-aminophenylthiyl radical generated by the photodissociation of bis(p-aminophenyl)disulfide. Time profiles of the peak shifts from the transient absorption and emission spectra after photodissociation were extracted to discuss the solvent reorganization process in various ionic liquids (ILs) with different viscosities. The absorption peak position of the radical followed common solvation dynamics, shifting to a lower energy with time due to reorganization of the surrounding solvent molecules in response to the charge redistribution and molecular volume change caused by photodissociation. On the other hand, the emission band of the radical did not show a meaningful spectral shift with time. It was also found that the solvation time in the ground state was not strongly dependent on the solvent viscosity. These experimental results deviate from the conventional dynamic Stokes shift theory. To discuss the experimental results, non-equilibrium molecular dynamics simulations were conducted. The spectral shift obtained by MD simulations indicated the existence of a large solvation energy change and solvation dynamics around the radical after the photodissociation. On the other hand, the electronic excitation of the radical brought about a relatively smaller solvation energy change, especially at the long delay time after the photodissociation. These differences might be one of the reasons for the unique experimentally observed solvation dynamics.
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Affiliation(s)
- Kaori Fujii
- Department of Applied Chemistry, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan.
| | - Hiroshi Nakano
- Department of Molecular Engineering, Kyoto University, Kyoto Daigaku Katsura, Kyoto 615-8510, Japan
| | - Hirofumi Sato
- Department of Molecular Engineering, Kyoto University, Kyoto Daigaku Katsura, Kyoto 615-8510, Japan
| | - Yoshifumi Kimura
- Department of Applied Chemistry, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan.
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Femtosecond solvation dynamics study of hydrophobic and hydrophilic probes in various room temperature ionic liquids (RTILs) containing microemulsions. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2021.138356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Robles-Hernández B, González E, Pomposo JA, Colmenero J, Alegría Á. Water dynamics and self-assembly of single-chain nanoparticles in concentrated solutions. SOFT MATTER 2020; 16:9738-9745. [PMID: 32996537 DOI: 10.1039/d0sm01447h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Single-chain polymer nanoparticles (SCNPs) are soft nano-objects consisting of uni-macromolecular chains collapsed to a certain degree by intramolecular crosslinking. The similarities between the behaviour of SCNPs and that of intrinsically disordered proteins suggest that SCNPs in concentrated solutions can be used as models to design artificial micro-environments, which mimic many of the general aspects of cellular environments. In this work, the self-assembly into SCNPs of an amphiphilic random copolymer, composed by oligo(ethylene glycol)methyl ether methacrylate (OEGMA) and 2-acetoacetoxy ethyl methacrylate (AEMA), has been investigated by means of the dielectric relaxation of water. Direct evidence of segregation of the AEMA repeating units is provided by comparison with the dielectric relaxation of water in similar solutions of the linear hydrophilic polymer, P(OEGMA). Furthermore, the results of comparative studies with similar water solutions of an amphiphilic block copolymer forming multi-chain micelles support the single-chain character of the self-assembly of the random copolymer. The overall obtained results highlight the suitability of the dielectric spectroscopy to confirm the self-assembly of the amphiphilic random copolymers into globular like core-shell single-chain nanoparticles at a concentration well above the overlap concentration.
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Affiliation(s)
- Beatriz Robles-Hernández
- Departamento de Polímeros y Materiales Avanzados, Física, Química y Tecnología, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain.
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