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Vázquez-Tato MP, Seijas JA, Meijide F, de Frutos S, Vázquez Tato J. Analysis of the Electron Density of a Water Molecule Encapsulated by Two Cholic Acid Residues. Int J Mol Sci 2023; 24:ijms24065359. [PMID: 36982433 PMCID: PMC10048964 DOI: 10.3390/ijms24065359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/28/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023] Open
Abstract
Cholic acid is a trihydroxy bile acid with a nice peculiarity: the average distance between the oxygen atoms (O7 and O12) of the hydroxy groups located at C7 and C12 carbon atoms is 4.5 Å, a value which perfectly matches with the O/O tetrahedral edge distance in Ih ice. In the solid phase, they are involved in the formation of hydrogen bonds with other cholic acid units and solvents. This fact was satisfactorily used for designing a cholic dimer which encapsulates one single water molecule between two cholic residues, its oxygen atom (Ow) being exactly located at the centroid of a distorted tetrahedron formed by the four steroid hydroxy groups. The water molecule participates in four hydrogen bonds, with the water simultaneously being an acceptor from the 2 O12 (hydrogen lengths are 2.177 Å and 2.114 Å) and a donor towards the 2 O7 (hydrogen bond lengths are 1.866 Å and 1.920 Å). These facts suggest that this system can be a nice model for the theoretical study of the formation of ice-like structures. These are frequently proposed to describe the water structure found in a plethora of systems (water interfaces, metal complexes, solubilized hydrophobic species, proteins, and confined carbon nanotubes). The above tetrahedral structure is proposed as a reference model for those systems, and the results obtained from the application of the atoms in molecules theory are presented here. Furthermore, the structure of the whole system allows a division into two interesting subsystems in which water is the acceptor of one hydrogen bond and the donor of another. The analysis of the calculated electron density is performed through its gradient vector and the Laplacian. The calculation of the complexation energy used correction of the basis set superposition error (BSSE) with the counterpoise method. As expected, four critical points located in the H…O bond paths were identified. All calculated parameters obey the proposed criteria for hydrogen bonds. The total energy for the interaction in the tetrahedral structure is 54.29 kJ/mol, while the summation obtained of the two independent subsystems and the one between the alkyl rings without water is only 2.5 kJ/mol higher. This concordance, together with the calculated values for the electron density, the Laplacian of the electron density, and the lengths of the oxygen atom and the hydrogen atom (involved in the formation of each hydrogen bond) to the hydrogen bond critical point, suggests that each pair of hydrogen bonds can be considered independent of each other.
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Affiliation(s)
- María Pilar Vázquez-Tato
- Departamento de Química Orgánica, Facultade de Ciencias, Universidade de Santiago de Compostela, Campus Terra, 27080 Lugo, Spain
| | - Julio A. Seijas
- Departamento de Química Orgánica, Facultade de Ciencias, Universidade de Santiago de Compostela, Campus Terra, 27080 Lugo, Spain
- Correspondence:
| | - Francisco Meijide
- Departamento de Química Física, Facultade de Ciencias, Universidade de Santiago de Compostela, Campus Terra, 27080 Lugo, Spain
| | - Santiago de Frutos
- Departamento de Química Física, Facultade de Ciencias, Universidade de Santiago de Compostela, Campus Terra, 27080 Lugo, Spain
| | - José Vázquez Tato
- Departamento de Química Física, Facultade de Ciencias, Universidade de Santiago de Compostela, Campus Terra, 27080 Lugo, Spain
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2
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Konstantinovsky D, Perets EA, Santiago T, Velarde L, Hammes-Schiffer S, Yan ECY. Detecting the First Hydration Shell Structure around Biomolecules at Interfaces. ACS CENTRAL SCIENCE 2022; 8:1404-1414. [PMID: 36313165 PMCID: PMC9615115 DOI: 10.1021/acscentsci.2c00702] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Indexed: 05/15/2023]
Abstract
Understanding the role of water in biological processes remains a central challenge in the life sciences. Water structures in hydration shells of biomolecules are difficult to study in situ due to overwhelming background from aqueous environments. Biological interfaces introduce additional complexity because biomolecular hydration differs at interfaces compared to bulk solution. Here, we perform experimental and computational studies of chiral sum frequency generation (chiral SFG) spectroscopy to probe chirality transfer from a protein to the surrounding water molecules. This work reveals that chiral SFG probes the first hydration shell around the protein almost exclusively. We explain the selectivity to the first hydration shell in terms of the asymmetry induced by the protein structure and specific protein-water hydrogen-bonding interactions. This work establishes chiral SFG as a powerful technique for studying hydration shell structures around biomolecules at interfaces, presenting new possibilities to address grand research challenges in biology, including the molecular origins of life.
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Affiliation(s)
- Daniel Konstantinovsky
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520, United States
- Department
of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Ethan A. Perets
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Ty Santiago
- Department
of Chemistry, University at Buffalo, Buffalo, New York 14260, United States
| | - Luis Velarde
- Department
of Chemistry, University at Buffalo, Buffalo, New York 14260, United States
| | | | - Elsa C. Y. Yan
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520, United States
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3
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Amarpuri G, Dhopatkar N, Blackledge TA, Dhinojwala A. Molecular Changes in Spider Viscid Glue As a Function of Relative Humidity Revealed Using Infrared Spectroscopy. ACS Biomater Sci Eng 2022; 8:3354-3360. [PMID: 35894694 DOI: 10.1021/acsbiomaterials.2c00529] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Spider aggregate glue can absorb moisture from the atmosphere to reduce its viscosity and become tacky. The viscosity at which glue adhesion is maximized is remarkably similar across spider species, even though that viscosity is achieved at very different relative humidity (RH) values matching their diverse habitats. However, the molecular changes in the protein structure and the bonding state of water (both referred to here as molecular structure) with respect to the changes in RH are not known. We use attenuated total reflectance-infrared (ATR-IR) spectroscopy to probe the changes in the molecular structure of glue as a function of RH for three spider species from different habitats. We find that the glue retains bound water at lower RH and absorbs liquid-like water at higher RH. The absorption of liquid-like water at high RH plasticizes the glue and explains the decrease in glue viscosity. The changes to protein conformations as a function RH are either subtle or not detectable by IR spectroscopy. Importantly, the molecular changes are reversible over multiple cycles of RH change. Further, separation of glue constituents results in a different humidity response as compared to pristine glue, supporting the standing hypothesis that the glue constituents have a synergistic association that makes spider glue a functional adhesive. The results presented in this study provide further insights into the mechanism of the humidity-responsive adhesion of spider glue.
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Affiliation(s)
- Gaurav Amarpuri
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Nishad Dhopatkar
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Todd A Blackledge
- Department of Biology, Integrated Bioscience Program, The University of Akron, Akron, Ohio 44325, United States
| | - Ali Dhinojwala
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
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4
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Madzharova F, Bregnhøj M, Chatterley AS, Løvschall KB, Drace T, Andersen Dreyer LS, Boesen T, Weidner T. Electrostatics Trigger Interfacial Self-Assembly of Bacterial Ice Nucleators. Biomacromolecules 2021; 23:505-512. [PMID: 34846123 DOI: 10.1021/acs.biomac.1c01217] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ice active bacteria can catalyze water freezing at high subzero temperatures using ice nucleating proteins (INPs) located at their outer cell walls. INPs are the most effective ice nucleators known and are of significant interest for agriculture, climate research, and freeze/antifreeze technologies. The aggregation of INPs into large ice nucleation sites is a key step for effective ice nucleation. It has been proposed that ice active bacteria can drive the aggregation of INPs and thereby trigger ice nucleation. However, the mechanism of INP aggregate assembly and the molecular processes behind the activation are still unclear. Both biochemical pathways and activation through electrostatics have been proposed based on experiments with lysed ice active bacteria. For a more direct view on the assembly of INPs, we follow the structure and water interactions of a synthetic model INP of the well-studied ice bacterium Pseudomonas syringae at the air-water interface as a function of the subphase pH. By combining sum frequency generation spectroscopy with two-dimensional infrared spectra, we conclude that self-assembly and electrostatic interactions drive the formation of ordered INP structures capable of aligning interfacial water.
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Affiliation(s)
- Fani Madzharova
- Department of Chemistry, Aarhus University, Aarhus C 8000, Denmark
| | - Mikkel Bregnhøj
- Department of Chemistry, Aarhus University, Aarhus C 8000, Denmark
| | | | | | - Taner Drace
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C 8000, Denmark.,Interdisciplinary Nanoscience Center-iNano, Aarhus University, Aarhus C 8000, Denmark
| | | | - Thomas Boesen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C 8000, Denmark.,Interdisciplinary Nanoscience Center-iNano, Aarhus University, Aarhus C 8000, Denmark
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, Aarhus C 8000, Denmark
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5
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Roeters SJ, Golbek TW, Bregnhøj M, Drace T, Alamdari S, Roseboom W, Kramer G, Šantl-Temkiv T, Finster K, Pfaendtner J, Woutersen S, Boesen T, Weidner T. Ice-nucleating proteins are activated by low temperatures to control the structure of interfacial water. Nat Commun 2021; 12:1183. [PMID: 33608518 PMCID: PMC7895962 DOI: 10.1038/s41467-021-21349-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 01/22/2021] [Indexed: 11/17/2022] Open
Abstract
Ice-nucleation active (INA) bacteria can promote the growth of ice more effectively than any other known material. Using specialized ice-nucleating proteins (INPs), they obtain nutrients from plants by inducing frost damage and, when airborne in the atmosphere, they drive ice nucleation within clouds, which may affect global precipitation patterns. Despite their evident environmental importance, the molecular mechanisms behind INP-induced freezing have remained largely elusive. We investigate the structural basis for the interactions between water and the ice-nucleating protein InaZ from the INA bacterium Pseudomonas syringae. Using vibrational sum-frequency generation (SFG) and two-dimensional infrared spectroscopy, we demonstrate that the ice-active repeats of InaZ adopt a β-helical structure in solution and at water surfaces. In this configuration, interaction between INPs and water molecules imposes structural ordering on the adjacent water network. The observed order of water increases as the interface is cooled to temperatures close to the melting point of water. Experimental SFG data combined with molecular-dynamics simulations and spectral calculations show that InaZ reorients at lower temperatures. This reorientation can enhance water interactions, and thereby the effectiveness of ice nucleation. Ice-nucleating proteins promote ice formation at high sub-zero temperatures, but the mechanism is still unclear. The authors investigate a model ice-nucleating protein at the air-water interface using vibrational sum frequency generation spectroscopy and simulations, revealing its reorientation at low temperatures, which increases contact with water molecules and promotes their ordering.
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Affiliation(s)
- Steven J Roeters
- Department of Chemistry, Aarhus University, Aarhus C, Denmark.,Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | | | - Mikkel Bregnhøj
- Department of Chemistry, Aarhus University, Aarhus C, Denmark
| | - Taner Drace
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | - Sarah Alamdari
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - Winfried Roseboom
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Gertjan Kramer
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Tina Šantl-Temkiv
- Department of Biology, Aarhus University, Aarhus C, Denmark.,The Stellar Astrophysics Centre - SAC, Department of Physics and Astronomy, Aarhus University, Aarhus C, Denmark
| | - Kai Finster
- Department of Biology, Aarhus University, Aarhus C, Denmark.,The Stellar Astrophysics Centre - SAC, Department of Physics and Astronomy, Aarhus University, Aarhus C, Denmark
| | - Jim Pfaendtner
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - Sander Woutersen
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Thomas Boesen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark.,Interdisciplinary Nanoscience Center - iNano, Aarhus University, Aarhus C, Denmark
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, Aarhus C, Denmark. .,Department of Chemical Engineering, University of Washington, Seattle, WA, USA. .,Interdisciplinary Nanoscience Center - iNano, Aarhus University, Aarhus C, Denmark.
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6
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Abstract
Lipid membranes are more than just barriers between cell compartments; they provide molecular environments with a finely tuned balance between hydrophilic and hydrophobic interactions that enable proteins to dynamically fold and self-assemble to regulate biological function. Characterizing dynamics at the lipid-water interface is essential to understanding molecular complexities from the thermodynamics of liquid-liquid phase separation down to picosecond-scale reorganization of interfacial hydrogen-bond networks.Ultrafast vibrational spectroscopy, including two-dimensional infrared (2D IR) and vibrational sum-frequency generation (VSFG) spectroscopies, is a powerful tool to examine picosecond interfacial dynamics. Two-dimensional IR spectroscopy provides a bond-centered view of dynamics with subpicosecond time resolutions, as vibrational frequencies are highly sensitive to the local environment. Recently, 2D IR spectroscopy has been applied to carbonyl and phosphate vibrations intrinsically located at the lipid-water interface. Interface-specific VSFG spectroscopy probes the water vibrational modes directly, accessing H-bond strength and water organization at lipid headgroup positions. Signals in VSFG arise from the interfacial dipole contributions, directly probing headgroup ordering and water orientation to provide a structural view of the interface.In this Account we discuss novel applications of ultrafast spectroscopy to lipid membranes, a field that has experienced significant growth over the past decade. In particular, ultrafast experiments now offer a molecular perspective on increasingly complex membranes. The powerful combination of ultrafast, interface-selective spectroscopy and simulations opens up new routes to understanding multicomponent membranes and their function. This Account highlights key prevailing views that have emerged from recent experiments: (1) Water dynamics at the lipid-water interface are slow compared to those of bulk water as a result of disrupted H-bond networks near the headgroups. (2) Peptides, ions, osmolytes, and cosolvents perturb interfacial dynamics, indicating that dynamics at the interface are affected by bulk solvent dynamics and vice versa. (3) The interfacial environment is generally dictated by the headgroup structure and orientation, but hydrophobic interactions within the acyl chains also modulate interfacial dynamics. Ultrafast spectroscopy has been essential to characterizing the biophysical chemistry of the lipid-water interface; however, challenges remain in interpreting congested spectra as well as designing appropriate model systems to capture the complexity of a membrane environment.
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Affiliation(s)
- Jennifer C. Flanagan
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street Stop A5300, Austin, Texas 78712-1224, United States
| | - Mason L. Valentine
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street Stop A5300, Austin, Texas 78712-1224, United States
| | - Carlos R. Baiz
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street Stop A5300, Austin, Texas 78712-1224, United States
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7
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Wang C, Luo Y, Li X, Zhang F, Wang F, Han X, Wang T, Beke-Somfai T, Lu X. Revealing Molecular-Level Interaction between a Polymeric Drug and Model Membrane Via Sum Frequency Generation and Microfluidics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:1615-1622. [PMID: 31967838 DOI: 10.1021/acs.langmuir.9b03676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Body fluids flow all over the body and affect the biological processes at biointerfaces. To simulate such a case, sum frequency generation (SFG) vibrational spectroscopy and a self-designed microfluidic chip were combined together to investigate the interaction between a pH-responsive polymeric drug, poly(α-propylacrylic acid) (PPAAc), and the model cell membranes in different liquid environments. By examining the SFG spectra under the static and flowing conditions, the drug-membrane interaction was revealed comprehensively. The interfacial water layer was screened as the key factor affecting the drug-membrane interaction. The interfacial water layer can prevent the side propyl groups on PPAAc from inserting into the model cell membrane but would be disrupted by numerous ions in buffer solutions. Without flowing, at pH 6.6, the interaction between PPAAc and the model cell membrane was strongest; with flowing, at pH 5.8, the interaction was strongest. Flowing was proven to substantially affect the interaction between PPAAc and the model cell membranes, suggesting that the fluid environment was of key significance for biointerfaces. This work demonstrated that, by combining SFG and microfluidics, new information about the molecular-level interaction between macromolecules and the model cell membranes can be acquired, which cannot be obtained by collecting the normal static SFG spectra.
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Affiliation(s)
- Chu Wang
- Department of Biomedical Engineering , Southeast University , Jiangsu 210096 , China
| | - Yongsheng Luo
- Department of Biomedical Engineering , Southeast University , Jiangsu 210096 , China
| | - Xu Li
- Department of Biomedical Engineering , Southeast University , Jiangsu 210096 , China
| | - Furong Zhang
- Department of Biomedical Engineering , Southeast University , Jiangsu 210096 , China
| | - Feng Wang
- Department of Biomedical Engineering , Southeast University , Jiangsu 210096 , China
| | - Xiaofeng Han
- Department of Biomedical Engineering , Southeast University , Jiangsu 210096 , China
| | - Ting Wang
- Department of Biomedical Engineering , Southeast University , Jiangsu 210096 , China
| | - Tamás Beke-Somfai
- Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences , Hungarian Academy of Sciences , H-1117 Budapest , Hungary
| | - Xiaolin Lu
- Department of Biomedical Engineering , Southeast University , Jiangsu 210096 , China
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8
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Su Z, Juhaniewicz-Debinska J, Sek S, Lipkowski J. Water Structure in the Submembrane Region of a Floating Lipid Bilayer: The Effect of an Ion Channel Formation and the Channel Blocker. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:409-418. [PMID: 31815479 DOI: 10.1021/acs.langmuir.9b03271] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The structure of water in the submembrane region of the bilayer of DPhPC floating (fBLM) on a monolayer of 1-thio-β-d-glucose (β-Tg)-modified gold nanoparticle film was studied by the surface-enhanced infrared absorption spectroscopy (SEIRAS). SEIRAS employs surface enhancement of the mean square electric field of the photon, which is acting on a few molecular layers above the film of gold nanoparticles. Therefore, it is uniquely suited to probe water molecules in the submembrane region and provides unique information concerning the structure of the hydrogen bond network of water surrounding the lipid bilayer. The IR spectra indicated that water with a strong hydrogen network is separating the membrane from the gold surface. This water is more ordered than the water in the bulk. When alamethicin, a peptide forming ion channels, is inserted into the membrane, the network is only slightly loosened. The addition of amiloride, an ion channel blocker, results in a significant decrease in the amount of water in the submembrane region. The remaining water has a significantly distorted hydrogen bond network. This study provides unique information about the effect of the ion channel on water transport across the bilayer. The electrode potential has a relatively small effect on water structure in the submembrane region. However, the IR studies demonstrated that water is less ordered at positive transmembrane potentials. The present results provide significant insight into the nature of hydration of a floating lipid bilayer on the gold electrode surface.
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Affiliation(s)
- ZhangFei Su
- Department of Chemistry , University of Guelph , Guelph , Ontario N1G 2W1 , Canada
| | - Joanna Juhaniewicz-Debinska
- Faculty of Chemistry, Biological and Chemical Research Centre , University of Warsaw , Żwirki i Wigury 101 , 02-089 Warsaw , Poland
| | - Slawomir Sek
- Department of Chemistry , University of Guelph , Guelph , Ontario N1G 2W1 , Canada
- Faculty of Chemistry, Biological and Chemical Research Centre , University of Warsaw , Żwirki i Wigury 101 , 02-089 Warsaw , Poland
| | - Jacek Lipkowski
- Department of Chemistry , University of Guelph , Guelph , Ontario N1G 2W1 , Canada
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9
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Kaur G, Chaudhary M, Jena KC, Singh N. Terbium(iii)-coated carbon quantum dots for the detection of clomipramine through aggregation-induced emission from the analyte. NEW J CHEM 2020. [DOI: 10.1039/d0nj01814g] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
CQD-Tb: a selective chemosensor for detecting the antidepressant drug clomipramine in aqueous media.
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Affiliation(s)
- Gurpreet Kaur
- Post Graduate Department of Chemistry
- Sri Guru Gobind Singh College
- Chandigarh
- India
| | - Monika Chaudhary
- Centre for Biomedical Engineering
- Indian Institute of Technology Ropar
- Roopnagar
- India
| | - Kailash C. Jena
- Centre for Biomedical Engineering
- Indian Institute of Technology Ropar
- Roopnagar
- India
- Department of Physics
| | - Narinder Singh
- Department of Chemistry, Indian Institute of Technology Ropar
- Roopnagar
- India
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10
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Perets EA, Yan ECY. Chiral Water Superstructures around Antiparallel β-Sheets Observed by Chiral Vibrational Sum Frequency Generation Spectroscopy. J Phys Chem Lett 2019; 10:3395-3401. [PMID: 31070921 PMCID: PMC9059516 DOI: 10.1021/acs.jpclett.9b00878] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Hydration modulates every aspect of protein structure and function. However, studying water structures in hydration shells remains challenging mostly due to overwhelming background from bulk water. We used vibrational sum frequency generation (SFG) spectroscopy to characterize hydrated films of an antiparallel β-sheet peptide (LK7β) adsorbed on glass slides. The hydrated films give chiral SFG response from water only when the peptide self-assembles into antiparallel β-sheets. Experiments of isotopic labeling, isotopic dilution of water, and H2O-D2O exchange kinetics corroborate the assignments of the chiral SFG response to water stretching modes. Because individual water molecules are achiral, the chiral SFG response indicates formation of chiral superstructures of water around the antiparallel β-sheet, implying that a protein secondary structure can imprint its chirality onto the surrounding water. This result demonstrates chiral SFG spectroscopy as a promising tool for probing water structures in protein hydration and addressing fundamental questions of protein structure-function.
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Affiliation(s)
- Ethan A. Perets
- Department of Chemistry, Yale University, New Haven, Connecticut 06520 United States
| | - E. Chui-Ying Yan
- Department of Chemistry, Yale University, New Haven, Connecticut 06520 United States
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11
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Dalchand N, Doğangün M, Ohno PE, Ma E, Martinson ABF, Geiger FM. Perturbation of Hydrogen-Bonding Networks over Supported Lipid Bilayers by Poly(allylamine hydrochloride). J Phys Chem B 2019; 123:4251-4257. [PMID: 31013086 DOI: 10.1021/acs.jpcb.9b02392] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Water is vital to many biochemical processes and is necessary for driving fundamental interactions of cell membranes with their external environments, yet it is difficult to probe the membrane/water interface directly and without the use of external labels. Here, we employ vibrational sum frequency generation spectroscopy to understand the role of interfacial water molecules above bilayers formed from zwitterionic (phosphatidylcholine) and anionic (phosphatidylglycerol, PG, and phosphatidylserine, PS) lipids as they are exposed to the common polycation poly(allylamine hydrochloride) (PAH) in 100 mM NaCl. We show that as the concentration of PAH is increased, the interfacial water molecules are irreversibly displaced and find that it requires 10 times more PAH to displace interfacial water molecules from membranes formed from purely zwitterionic lipids when compared to membranes that contain the anionic PG and PS lipids. This outcome is likely due to the difference in (1) the energy with which water molecules are bound to the lipid headgroups, (2) the number of water molecules bound to the headgroups, which is related to the headgroup area, and (3) the electrostatic interactions between the PAH molecules and the negatively charged lipids that are favored when compared to the zwitterionic lipid headgroups. The findings presented here contribute to establishing causal relationships in nanotoxicology and to understanding, controlling, and predicting the initial steps that lead to the lysis of cells exposed to membrane-disrupting polycations or to transfection.
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Affiliation(s)
- Naomi Dalchand
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Merve Doğangün
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Paul E Ohno
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Emily Ma
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Alex B F Martinson
- Materials Science Division , Argonne National Laboratory , 9700 S. Cass Avenue , Argonne, Lemont , Illinois 40439 , United States
| | - Franz M Geiger
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
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12
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Doǧangün M, Ohno PE, Liang D, McGeachy AC, Bé AG, Dalchand N, Li T, Cui Q, Geiger FM. Hydrogen-Bond Networks near Supported Lipid Bilayers from Vibrational Sum Frequency Generation Experiments and Atomistic Simulations. J Phys Chem B 2018; 122:4870-4879. [PMID: 29688732 DOI: 10.1021/acs.jpcb.8b02138] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We report vibrational sum frequency generation (SFG) spectra in which the C-H stretches of lipid alkyl tails in fully hydrogenated single- and dual-component supported lipid bilayers are detected along with the O-H stretching continuum above the bilayer. As the salt concentration is increased from ∼10 μM to 0.1 M, the SFG intensities in the O-H stretching region decrease by a factor of 2, consistent with significant absorptive-dispersive mixing between χ(2) and χ(3) contributions to the SFG signal generation process from charged interfaces. A method for estimating the surface potential from the second-order spectral lineshapes (in the OH stretching region) is presented and discussed in the context of choosing truly zero-potential reference states. Aided by atomistic simulations, we find that the strength and orientation distribution of the hydrogen bonds over the purely zwitterionic bilayers are largely invariant between submicromolar and hundreds of millimolar concentrations. However, specific interactions between water molecules and lipid headgroups are observed upon replacing phosphocholine (PC) lipids with negatively charged phosphoglycerol (PG) lipids, which coincides with SFG signal intensity reductions in the 3100-3200 cm-1 frequency region. The atomistic simulations show that this outcome is consistent with a small, albeit statistically significant, decrease in the number of water molecules adjacent to both the lipid phosphate and choline moieties per unit area, supporting the SFG observations. Ultimately, the ability to probe hydrogen-bond networks over lipid bilayers holds the promise of opening paths for understanding, controlling, and predicting specific and nonspecific interactions between membranes and ions, small molecules, peptides, polycations, proteins, and coated and uncoated nanomaterials.
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Affiliation(s)
- Merve Doǧangün
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Paul E Ohno
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Dongyue Liang
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - Alicia C McGeachy
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Ariana Gray Bé
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Naomi Dalchand
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Tianzhe Li
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
| | - Qiang Cui
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States.,Department of Chemistry , Boston University , 590 Commonwealth Avenue , Boston , Massachusetts 02215 , United States
| | - Franz M Geiger
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60660 , United States
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13
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Franz J, van Zadel MJ, Weidner T. A trough for improved SFG spectroscopy of lipid monolayers. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:053106. [PMID: 28571440 DOI: 10.1063/1.4982050] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Lipid monolayers are indispensable model systems for biological membranes. The main advantage over bilayer model systems is that the surface pressure within the layer can be directly and reliably controlled. The sensitive interplay between surface pressure and temperature determines the molecular order within a model membrane and consequently determines the membrane phase behavior. The lipid phase is of crucial importance for a range of membrane functions such as protein interactions and membrane permeability. A very reliable method to probe the structure of lipid monolayers is sum frequency generation (SFG) vibrational spectroscopy. Not only is SFG extremely surface sensitive but it can also directly access critical parameters such as lipid order and orientation, and it can provide valuable information about protein interactions along with interfacial hydration. However, recent studies have shown that temperature gradients caused by high power laser beams perturb the lipid layers and potentially obscure the spectroscopic results. Here we demonstrate how the local heating problem can be effectively reduced by spatially distributing the laser pulses on the sample surface using a translating Langmuir trough for SFG experiments at lipid monolayers. The efficiency of the trough is illustrated by the detection of enhanced molecular order due to reduced heat load.
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Affiliation(s)
- Johannes Franz
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, Mainz 55128, Germany
| | - Marc-Jan van Zadel
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, Mainz 55128, Germany
| | - Tobias Weidner
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, Mainz 55128, Germany
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14
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Braunschweig B, Schulze-Zachau F, Nagel E, Engelhardt K, Stoyanov S, Gochev G, Khristov K, Mileva E, Exerowa D, Miller R, Peukert W. Specific effects of Ca(2+) ions and molecular structure of β-lactoglobulin interfacial layers that drive macroscopic foam stability. SOFT MATTER 2016; 12:5995-6004. [PMID: 27337699 PMCID: PMC5048339 DOI: 10.1039/c6sm00636a] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 06/12/2016] [Indexed: 06/01/2023]
Abstract
β-Lactoglobulin (BLG) adsorption layers at air-water interfaces were studied in situ with vibrational sum-frequency generation (SFG), tensiometry, surface dilatational rheology and ellipsometry as a function of bulk Ca(2+) concentration. The relation between the interfacial molecular structure of adsorbed BLG and the interactions with the supporting electrolyte is additionally addressed on higher length scales along the foam hierarchy - from the ubiquitous air-water interface through thin foam films to macroscopic foam. For concentrations <1 mM, a strong decrease in SFG intensity from O-H stretching bands and a slight increase in layer thickness and surface pressure are observed. A further increase in Ca(2+) concentrations above 1 mM causes an apparent change in the polarity of aromatic C-H stretching vibrations from interfacial BLG which we associate to a charge reversal at the interface. Foam film measurements show formation of common black films at Ca(2+) concentrations above 1 mM due to considerable decrease of the stabilizing electrostatic disjoining pressure. These observations also correlate with a minimum in macroscopic foam stability. For concentrations >30 mM Ca(2+), micrographs of foam films show clear signatures of aggregates which tend to increase the stability of foam films. Here, the interfacial layers have a higher surface dilatational elasticity. In fact, macroscopic foams formed from BLG dilutions with high Ca(2+) concentrations where aggregates and interfacial layers with higher elasticity are found, showed the highest stability with much smaller bubble sizes.
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Affiliation(s)
- Björn Braunschweig
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany. and Cluster of Excellence Engineering of Advanced Materials (EAM), Nägelsbachstr. 49b, 91052 Erlangen, Germany and Erlangen Graduate School in Advanced Optical Technologies (SAOT), Paul-Gordan-Straße 6, 91052 Erlangen, Germany and Interdisciplinary Center of Functional Particle Systems, Haberstraße 9a, 91058 Erlangen, Germany
| | - Felix Schulze-Zachau
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany. and Erlangen Graduate School in Advanced Optical Technologies (SAOT), Paul-Gordan-Straße 6, 91052 Erlangen, Germany and Interdisciplinary Center of Functional Particle Systems, Haberstraße 9a, 91058 Erlangen, Germany
| | - Eva Nagel
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany.
| | - Kathrin Engelhardt
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany.
| | - Stefan Stoyanov
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Georgi Gochev
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria and Max-Planck-Institute of Colloids and Interfaces, 14476 Golm/Potsdam, Germany
| | - Khr Khristov
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Elena Mileva
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Dotchi Exerowa
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Reinhard Miller
- Max-Planck-Institute of Colloids and Interfaces, 14476 Golm/Potsdam, Germany
| | - Wolfgang Peukert
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany. and Cluster of Excellence Engineering of Advanced Materials (EAM), Nägelsbachstr. 49b, 91052 Erlangen, Germany and Erlangen Graduate School in Advanced Optical Technologies (SAOT), Paul-Gordan-Straße 6, 91052 Erlangen, Germany and Interdisciplinary Center of Functional Particle Systems, Haberstraße 9a, 91058 Erlangen, Germany
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15
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Tong Y, Kampfrath T, Campen RK. Experimentally probing the libration of interfacial water: the rotational potential of water is stiffer at the air/water interface than in bulk liquid. Phys Chem Chem Phys 2016; 18:18424-30. [PMID: 27339861 DOI: 10.1039/c6cp01004k] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Most properties of liquid water are determined by its hydrogen-bond network. Because forming an aqueous interface requires termination of this network, one might expect the molecular level properties of interfacial water to markedly differ from water in bulk. Intriguingly, much prior experimental and theoretical work has found that, from the perspective of their time-averaged structure and picosecond structural dynamics, hydrogen-bonded OH groups at an air/water interface behave the same as hydrogen-bonded OH groups in bulk liquid water. Here we report the first experimental observation of interfacial water's libration (i.e. frustrated rotation) using the laser-based technique vibrational sum frequency spectroscopy. We find this mode has a frequency of 834 cm(-1), ≈165 cm(-1) higher than in bulk liquid water at the same temperature and similar to bulk ice. Because libration frequency is proportional to the stiffness of water's rotational potential, this increase suggests that one effect of terminating bulk water's hydrogen bonding network at the air/water interface is retarding rotation of water around intact hydrogen bonds. Because in bulk liquid water the libration plays a key role in stabilizing reaction intermediates and dissipating excess vibrational energy, we expect the ability to probe this mode in interfacial water to open new perspectives on the kinetics of heterogeneous reactions at aqueous interfaces.
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Affiliation(s)
- Yujin Tong
- Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany.
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16
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Livingstone RA, Nagata Y, Bonn M, Backus EHG. Two Types of Water at the Water–Surfactant Interface Revealed by Time-Resolved Vibrational Spectroscopy. J Am Chem Soc 2015; 137:14912-9. [DOI: 10.1021/jacs.5b07845] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ruth A. Livingstone
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Ellen H. G. Backus
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
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17
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Jahn M, Gekle S. Bulk and interfacial liquid water as a transient network. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 92:052130. [PMID: 26651669 DOI: 10.1103/physreve.92.052130] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Indexed: 06/05/2023]
Abstract
The special macroscopic properties of liquid water stem from its structure as a complex network of molecules connected by hydrogen bonds. While the dynamics of single molecules within this network has been extensively investigated, only little attention has been paid to the closed loops (meshes) of hydrogen-bonded molecules which determine the network topology. Using molecular dynamics simulations we analyze the size, shape, geometrical arrangement, and dynamical stability of loops containing up to 10 hydrogen bonds. We find that six-membered loops in liquid water even at room temperature retain a striking similarity with the well-known structure of ice. Analyzing the network dynamics we find that rings of more than five hydrogen bonds are stabilized compared to a random collection containing the same number of single bonds. We finally show that in the vicinity of hydrophobic and hydrophilic interfaces loops arrange in a preferred orientation.
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Affiliation(s)
- Miriam Jahn
- Fachbereich Physik, Universität Bayreuth, Germany
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18
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Affiliation(s)
- Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 16610 Prague 6, Czech Republic
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19
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Beierlein FR, Clark T, Braunschweig B, Engelhardt K, Glas L, Peukert W. Carboxylate Ion Pairing with Alkali-Metal Ions for β-Lactoglobulin and Its Role on Aggregation and Interfacial Adsorption. J Phys Chem B 2015; 119:5505-17. [PMID: 25825918 DOI: 10.1021/acs.jpcb.5b01944] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a combined experimental and computational study of the whey protein β-lactoglobulin (BLG) in different electrolyte solutions. Vibrational sum-frequency generation (SFG) and ellipsometry were used to investigate the molecular structure of BLG modified air-water interfaces as a function of LiCl, NaCl, and KCl concentrations. Molecular dynamics (MD) simulations and thermodynamic integration provided details of the ion pairing of protein surface residues with alkali-metal cations. Our results at pH 6.2 indicate that BLG at the air-water interface forms mono- and bilayers preferably at low and high ionic strength, respectively. Results from SFG spectroscopy and ellipsometry are consistent with intimate ion pairing of alkali-metal cations with aspartate and glutamate carboxylates, which is shown to be more effective for smaller cations (Li(+) and Na(+)). MD simulations show not only carboxylate-alkali-metal ion pairs but also ion multiplets with the alkali-metal ion in a bridging position between two or more carboxylates. Consequently, alkali-metal cations can bridge carboxylates not only within a monomer but also between monomers, thus providing an important dimerization mechanism between hydrophilic surface patches.
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Affiliation(s)
- Frank R Beierlein
- †Computer-Chemie-Centrum and Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstr. 25, 91052 Erlangen, Germany.,‡Cluster of Excellence Engineering of Advanced Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstr. 49b, 91052 Erlangen, Germany
| | - Timothy Clark
- †Computer-Chemie-Centrum and Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstr. 25, 91052 Erlangen, Germany.,‡Cluster of Excellence Engineering of Advanced Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstr. 49b, 91052 Erlangen, Germany.,∥Centre for Molecular Design, University of Portsmouth, King Henry Building, King Henry I Street, Portsmouth PO1 2DY, United Kingdom
| | - Björn Braunschweig
- ‡Cluster of Excellence Engineering of Advanced Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstr. 49b, 91052 Erlangen, Germany.,§Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstraße 4, 91058 Erlangen, Germany
| | - Kathrin Engelhardt
- §Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstraße 4, 91058 Erlangen, Germany
| | - Lena Glas
- §Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstraße 4, 91058 Erlangen, Germany
| | - Wolfgang Peukert
- ‡Cluster of Excellence Engineering of Advanced Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstr. 49b, 91052 Erlangen, Germany.,§Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstraße 4, 91058 Erlangen, Germany
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20
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Bonn M, Nagata Y, Backus EHG. Untersuchung der Struktur und Dynamik von Wasser an der Wasser-Luft-Grenzfläche mittels oberflächenspezifischer Schwingungsspektroskopie. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201411188] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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21
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Bonn M, Nagata Y, Backus EHG. Molecular Structure and Dynamics of Water at the Water-Air Interface Studied with Surface-Specific Vibrational Spectroscopy. Angew Chem Int Ed Engl 2015; 54:5560-76. [DOI: 10.1002/anie.201411188] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Indexed: 11/07/2022]
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22
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Abstract
It is commonly assumed that the structure of water at a lipid-water interface is influenced mostly in the first hydration layer. However, recent results from different experimental methods show that perturbation extends through several hydration layers. Due to its low light penetration depth, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy is specifically suited to study interlamellar water structure in multibilayers. Results obtained by this technique confirm the long-range water structure disturbance. Consequently, in confined membrane environments nearly all water molecules can be perturbed. It is important to note that the behavior of confined water molecules differs significantly in samples prepared in excess water and in partially hydrated samples. We show in what manner the interlamellar water perturbation is influenced by the hydration level and how it is sequentially modified with a step-by-step dehydration of samples either by water evaporation or by osmotic pressure. Our results also indicate that besides different levels of hydration the lipid-water interaction is modulated by different lipid headgroups and different lipid phases as well. Therefore, modification of interlamellar water properties may clarify the role of water-mediated effects in biological processes.
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Affiliation(s)
- Zoran Arsov
- Laboratory of Biophysics, Department of Solid State Physics, "Jozef Stefan" Institute, Jamova 39, SI-1000, Ljubljana, Slovenia.
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23
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Feng RR, Guo Y, Wang HF. Reorientation of the “free OH” group in the top-most layer of air/water interface of sodium fluoride aqueous solution probed with sum-frequency generation vibrational spectroscopy. J Chem Phys 2014; 141:18C507. [PMID: 25399172 DOI: 10.1063/1.4895561] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Ran-Ran Feng
- International Center for Quantum Materials, Peking University, Beijing 100871, People's Republic of China
| | - Yuan Guo
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
| | - Hong-Fei Wang
- William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, Richland, Washington 99352, USA
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24
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Disalvo EA, Martini MF, Bouchet AM, Hollmann A, Frías MA. Structural and thermodynamic properties of water-membrane interphases: significance for peptide/membrane interactions. Adv Colloid Interface Sci 2014; 211:17-33. [PMID: 25085854 DOI: 10.1016/j.cis.2014.05.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 05/16/2014] [Accepted: 05/16/2014] [Indexed: 12/28/2022]
Abstract
Water appears as a common intermediary in the mechanisms of interaction of proteins and polypeptides with membranes of different lipid composition. In this review, how water modulates the interaction of peptides and proteins with lipid membranes is discussed by correlating the thermodynamic response and the structural changes of water at the membrane interphases. The thermodynamic properties of the lipid-protein interaction are governed by changes in the water activity of monolayers of different lipid composition according to the lateral surface pressure. In this context, different water populations can be characterized below and above the phase transition temperature in relation to the CH₂ conformers' states in the acyl chains. According to water species present at the interphase, lipid membrane acts as a water state regulator, which determines the interfacial water domains in the surface. It is proposed that those domains are formed by the contact between lipids themselves and between lipids and the water phase, which are needed to trigger adsorption-insertion processes. The water domains are essential to maintain functional dynamical properties and are formed by water beyond the hydration shell of the lipid head groups. These confined water domains probably carries information in local units in relation to the lipid composition thus accounting for the link between lipidomics and aquaomics. The analysis of these results contributes to a new insight of the lipid bilayer as a non-autonomous, responsive (reactive) structure that correlates with the dynamical properties of a living system.
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Affiliation(s)
- E A Disalvo
- Centro de Investigaciones y Transferencia Santiago del Estero (CITSE), (CONICET-UNSE), Laboratorio de Biointerfases y Sistemas Biomiméticos, Laboratorios Centrales - Ala Norte, Ruta Nacional 9, Km 1125 - Villa El Zanjón, CP 4206 Santiago del Estero, Argentina.
| | - M F Martini
- Department of Pharmaceutical Technology, Universidad de Buenos Aires, Buenos Aires, Argentina and CONICET
| | - A M Bouchet
- Centro de Investigaciones y Transferencia Santiago del Estero (CITSE), (CONICET-UNSE), Laboratorio de Biointerfases y Sistemas Biomiméticos, Laboratorios Centrales - Ala Norte, Ruta Nacional 9, Km 1125 - Villa El Zanjón, CP 4206 Santiago del Estero, Argentina
| | - A Hollmann
- Centro de Investigaciones y Transferencia Santiago del Estero (CITSE), (CONICET-UNSE), Laboratorio de Biointerfases y Sistemas Biomiméticos, Laboratorios Centrales - Ala Norte, Ruta Nacional 9, Km 1125 - Villa El Zanjón, CP 4206 Santiago del Estero, Argentina
| | - M A Frías
- Centro de Investigaciones y Transferencia Santiago del Estero (CITSE), (CONICET-UNSE), Laboratorio de Biointerfases y Sistemas Biomiméticos, Laboratorios Centrales - Ala Norte, Ruta Nacional 9, Km 1125 - Villa El Zanjón, CP 4206 Santiago del Estero, Argentina
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25
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Engelhardt K, Peukert W, Braunschweig B. Vibrational sum-frequency generation at protein modified air–water interfaces: Effects of molecular structure and surface charging. Curr Opin Colloid Interface Sci 2014. [DOI: 10.1016/j.cocis.2014.03.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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26
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Engelhardt K, Weichsel U, Kraft E, Segets D, Peukert W, Braunschweig B. Mixed Layers of β-Lactoglobulin and SDS at Air–Water Interfaces with Tunable Intermolecular Interactions. J Phys Chem B 2014; 118:4098-105. [DOI: 10.1021/jp501541q] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Kathrin Engelhardt
- Institute of Particle Technology
(LFG), University of Erlangen-Nuremberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Ulrike Weichsel
- Institute of Particle Technology
(LFG), University of Erlangen-Nuremberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Elena Kraft
- Institute of Particle Technology
(LFG), University of Erlangen-Nuremberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Doris Segets
- Institute of Particle Technology
(LFG), University of Erlangen-Nuremberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Wolfgang Peukert
- Institute of Particle Technology
(LFG), University of Erlangen-Nuremberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Björn Braunschweig
- Institute of Particle Technology
(LFG), University of Erlangen-Nuremberg, Cauerstrasse 4, 91058 Erlangen, Germany
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27
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Bisson PJ, Shultz MJ. Hydrogen bonding in the prism face of ice I(h) via sum frequency vibrational spectroscopy. J Phys Chem A 2013; 117:6116-25. [PMID: 23451801 DOI: 10.1021/jp400129f] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The prism face of single crystal ice I(h) has been studied using sum frequency vibrational spectroscopy focusing on identification of resonances in the hydrogen-bonded region. Several modes have been observed at about 3400 cm(-1); each mode is both polarization and orientation dependent. The polarization capabilities of sum frequency generation (SFG) are used in conjunction with the crystal orientation to characterize three vibrational modes. These modes are assigned to three-coordinated water molecules in the top-half bilayer having different bonding and orientation motifs.
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Affiliation(s)
- Patrick J Bisson
- Laboratory for Water and Surface Studies, Department of Chemistry, Pearson Laboratory, Tufts University, Medford, Massachusetts 02155, USA
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