Chiroptical Symmetry Analysis (CSA): on the Way from the Understanding of Highly Symmetric Systems to the Development of Chiroptical Applications

The high sensitivity of chiroptical responses to conformational changes and supramolecular interactions has prompted an increasing interest in the development of chiroptical applications. However, prediction and understanding the chiroptical responses of the necessary large systems may not be affordable for calculations at high levels of theory. In order to facilitate the development of chiroptical applications, methodologies capable of evaluating the chiroptical responses of large systems are necessary. Exciton chirality method has been extensively used for the interaction between two independent chromophores through the Davydov model. For systems presenting C2 or D2 symmetry one can get to the same results by applying the selection rules. In the present article, analysis of the selection rules for systems with symmetries Cn and Dn with n = 3 and 4 is used to uncover the origin of their chiroptical responses. We hope that the use of the chiroptical symmetry analysis (CSA) for systems presenting the symmetries explored herein as well as for systems presenting higher symmetries will serve as a useful tool for the development of chiroptical applications.

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Chiroptical Symmetry Analysis: Exciton Chirality-Based Formulae to Understand the Chiroptical Responses of Cn and Dn Symmetric Systems

Molecules ◽

10.3390/molecules24010141 ◽

2019 ◽

Vol 24 (1) ◽

pp. 141 ◽

Cited By ~ 2

Author(s):

Silvia Castro-Fernández ◽

Ángeles Peña-Gallego ◽

Ricardo A. Mosquera ◽

José Lorenzo Alonso-Gómez

Keyword(s):

Present Article ◽

Conformational Changes ◽

High Sensitivity ◽

Symmetry Analysis ◽

Supramolecular Interactions ◽

Selection Rules ◽

Higher Symmetries ◽

Large Systems ◽

Davydov Model ◽

Symmetric Systems

The high sensitivity of chiroptical responses to conformational changes and supramolecular interactions has prompted an increasing interest in the development of chiroptical applications. However, prediction of and understanding the chiroptical responses of the necessary large systems may not be affordable for calculations at high levels of theory. In order to facilitate the development of chiroptical applications, methodologies capable of evaluating the chiroptical responses of large systems are necessary. The exciton chirality method has been extensively used for the interaction between two independent chromophores through the Davydov model. For systems presenting C2 or D2 symmetry, one can get the same results by applying the selection rules. In the present article, the analysis of the selection rules for systems with symmetries Cn and Dn with n = 3 and 4 is used to uncover the origin of their chiroptical responses. We foresee that the use of the Chiroptical Symmetry Analysis (CSA) for systems presenting the symmetries explored herein, as well as for systems presenting higher symmetries will serve as a useful tool for the development of chiroptical applications.

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Las funciones del interregionalismo en la relación UE-CAN

Oikos ◽

10.29344/07184670.29.1010 ◽

2015 ◽

Vol 14 (29) ◽

pp. 13

Author(s):

Olga María Cerqueira Torres

Keyword(s):

European Union ◽

Present Article ◽

The Political ◽

The European Union ◽

Integration Process ◽

Association Agreement ◽

Political Rationality ◽

Article Analysis ◽

Andean Community ◽

The Eu

RESUMENEn el presente artículo el análisis se ha centrado en determinar cuáles de las funciones del interregionalismo, sistematizadas en los trabajos de Jürgen Rüland, han sido desarrolladas en la relación Unión Europea-Comunidad Andina de Naciones, ya que ello ha permitido evidenciar si el estado del proceso de integración de la CAN ha condicionado la racionalidad política del comportamiento de la Unión Europea hacia la región andina (civil power o soft imperialism); esto posibilitará establecer la viabilidad de la firma del Acuerdo de Asociación Unión Europea-Comunidad Andina de Naciones.Palabras clave: Unión Europea, Comunidad Andina, interregionalismo, funciones, acuerdo de asociación. Interregionalism functions in the EU-ANDEAN community relationsABSTRACTIn the present article analysis has focused on which functions of interregionalism, systematized by Jürgen Rüland, have been developed in the European Union-Andean Community birregional relation, that allowed demonstrate if the state of the integration process in the Andean Community has conditioned the political rationality of the European Union towards the Andean region (civil power or soft imperialism); with all these elements will be possible to establish the viability of the Association Agreement signature between the European Union and the Andean Community.Keywords: European Union, Andean Community, interregionalism, functions, association agreement.

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Insight to Functional Conformation and Noncovalent Interactions of Protein-Protein Assembly Using MALDI Mass Spectrometry

Molecules ◽

10.3390/molecules25214979 ◽

2020 ◽

Vol 25 (21) ◽

pp. 4979

Author(s):

Marco Giampà ◽

Elvira Sgobba

Keyword(s):

Mass Spectrometry ◽

Conformational Changes ◽

Protein Interactions ◽

Noncovalent Interactions ◽

Conformational Dynamics ◽

High Sensitivity ◽

Maldi Mass Spectrometry ◽

Noncovalent Interaction ◽

Ionization Mass ◽

Label Free

Noncovalent interactions are the keys to the structural organization of biomolecule e.g., proteins, glycans, lipids in the process of molecular recognition processes e.g., enzyme-substrate, antigen-antibody. Protein interactions lead to conformational changes, which dictate the functionality of that protein-protein complex. Besides biophysics techniques, noncovalent interaction and conformational dynamics, can be studied via mass spectrometry (MS), which represents a powerful tool, due to its low sample consumption, high sensitivity, and label-free sample. In this review, the focus will be placed on Matrix-Assisted Laser Desorption Ionization Mass Spectrometry (MALDI-MS) and its role in the analysis of protein-protein noncovalent assemblies exploring the relationship within noncovalent interaction, conformation, and biological function.

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The ligand mediated pseudohypersensitivity of the 3H4 → 3P2, 3H4 → 3P1, 3H4 → 3P0, and 3H4 → 1D2 transitions of praseodymium(III) complexes in solution media

Canadian Journal of Chemistry ◽

10.1139/v92-009 ◽

1992 ◽

Vol 70 (1) ◽

pp. 46-54 ◽

Cited By ~ 5

Author(s):

Sudhindra N. Misra ◽

Shaun O. Sommerer

Keyword(s):

Amino Acids ◽

Quantitative Analysis ◽

Present Article ◽

Oscillator Strength ◽

Schiff Bases ◽

High Sensitivity ◽

Structural Features ◽

Absorption Spectrophotometry ◽

Nucleic Bases ◽

Hypersensitive Transitions

The absorption difference, comparative absorption spectrophotometry, and quantitative analysis of 4f–4f spectra of praseodymium(III) complexes with ligands possessing varying structural features and binding capabilities have clearly indicated that the 3H4 → 3P2, 3H4 → 3P1, 3H4 → 3P0, and 3H4 → 1D2 transitions exhibit substantial intensification as well as a wide variation of oscillator strength. Since these transitions do not follow the selection rules they cannot be considered hypersensitive. Ligands such as β-diketones, Schiff bases, amino acids, diols, nucleic bases, nucleosides, nucleotides, alkoxides, and haloacetates with widely differing binding features in terms of coordinating ability, denticity, and normalized bite appear to induce, to varying degrees, high sensitivity in these non-hypersensitive transitions. The present article reports the high sensitivity of the 3H4 → 3P2, 3P1, 3P0, and 1D2, transitions of Pr(III) by considering the solution spectra of 173 species. This unique sensitivity is termed Ligand Mediated Pseudohypersensitivity. Keywords: praseodymium(III), 4f–4f transitions, hypersensitive transitions.

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Mutational Analysis of Active Site Residues Essential for Sensing of Organic Hydroperoxides by Bacillus subtilis OhrR

Journal of Bacteriology ◽

10.1128/jb.00879-07 ◽

2007 ◽

Vol 189 (19) ◽

pp. 7069-7076 ◽

Cited By ~ 16

Author(s):

Sumarin Soonsanga ◽

Mayuree Fuangthong ◽

John D. Helmann

Keyword(s):

Hydrogen Bond ◽

Bacillus Subtilis ◽

Conformational Changes ◽

Active Site ◽

Mutational Analysis ◽

High Sensitivity ◽

Oxidative Modification ◽

Active Site Residues

ABSTRACT Bacillus subtilis OhrR is the prototype for the one-Cys family of organic peroxide-sensing regulatory proteins. Mutational analyses indicate that the high sensitivity of the active site cysteine (C15) to peroxidation requires three Tyr residues. Y29 and Y40 from the opposing subunit of the functional dimer hydrogen bond with the reactive Cys thiolate, and substitutions at these positions reduce or eliminate the ability of OhrR to respond to organic peroxides. Y19 is also critical for peroxide sensing, and the Ala substitution mutant (OhrR Y19A) is less susceptible to oxidation at the active site C15 in vivo. The Y19A protein also displays decreased sensitivity to peroxide-mediated oxidation in vitro. Y19 is in van der Waals contact with two residues critical for protein function, F16 and R23. The latter residue makes critical contact with the DNA backbone in the OhrR-operator complex. These results indicate that the high sensitivity of the OhrR C15 residue to oxidation requires interactions with the opposed Tyr residues. Oxidative modification of C15 likely disrupts the C15-Y29′-Y40′ hydrogen bond network and thereby initiates conformational changes that reduce the ability of OhrR to bind to its operator site.

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Symmetry selection rules for vibrational excitation by resonant electron impact and a unified treatment of vibronic coupling between resonances and to the continuum: A complete symmetry analysis of vibrational excitation in benzene

The Journal of Chemical Physics ◽

10.1063/1.465346 ◽

1993 ◽

Vol 99 (2) ◽

pp. 827-835 ◽

Cited By ~ 35

Author(s):

G. A. Gallup

Keyword(s):

Electron Impact ◽

Vibrational Excitation ◽

Vibronic Coupling ◽

Symmetry Analysis ◽

Selection Rules ◽

Complete Symmetry ◽

Resonant Electron ◽

The Continuum

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Dual-color Fluorescence Cross-Correlation Spectroscopy to study Protein-Protein Interaction and Protein Dynamics in Live Cells

10.1101/2021.09.10.459760 ◽

2021 ◽

Author(s):

Katherina Hemmen ◽

Susobhan Choudhury ◽

Mike Friedrich ◽

Johannes Balkenhol ◽

Felix Knote ◽

...

Keyword(s):

Conformational Changes ◽

High Reliability ◽

Resonance Energy ◽

High Sensitivity ◽

Correlation Spectroscopy ◽

Live Cell ◽

Fluorescence Labeling ◽

Live Cells ◽

Noise Levels ◽

Dual Color

We present a protocol and workflow to perform live cell dual-color fluorescence crosscorrelation spectroscopy (FCCS) combined with Förster Resonance Energy transfer (FRET) to study membrane receptor dynamics in live cells using modern fluorescence labeling techniques. In dual-color FCCS, where the fluctuations in fluorescence intensity represents the dynamical "fingerprint" of the respective fluorescent biomolecule, we can probe co-diffusion or binding of the receptors. FRET, with its high sensitivity to molecular distances, serves as a well-known "nanoruler" to monitor intramolecular changes. Taken together, conformational changes and key parameters such as local receptor concentrations, and mobility constants become accessible in cellular settings. Quantitative fluorescence approaches are challenging in cells due to high noise levels and the vulnerable sample itself. We will show how to perform the experiments including the calibration steps. We use dual-color labeled β2-adrenergic receptor (β2AR) labeled (eGFP and SNAPtag-TAMRA). We will guide you step-by-step through the data analysis procedure using open-source software and provide templates that are easy to customize. Our guideline enables researchers to unravel molecular interactions of biomolecules in live cells in situ with high reliability despite the limited signal-to-noise levels in live cell experiments. The operational window of FRET and particularly FCCS at low concentrations allows quantitative analysis near-physiological conditions.

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Enhanced Sensitivity of a Love Wave-Based Methane Gas Sensor Incorporating a Cryptophane-A Thin Film

Sensors ◽

10.3390/s18103247 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3247 ◽

Cited By ~ 12

Author(s):

Wen Wang ◽

Shuyao Fan ◽

Yong Liang ◽

Shitang He ◽

Yong Pan ◽

...

Keyword(s):

Thin Film ◽

Wave Propagation ◽

Acoustic Wave ◽

Love Wave ◽

Temperature Stability ◽

High Sensitivity ◽

Supramolecular Interactions ◽

Propagation Path ◽

Vanillyl Alcohol ◽

Methane Gas

A Love wave-based sensing chip incorporating a supramolecular cryptophane A (CrypA) thin film was proposed for methane gas sensing in this work. The waveguide effect in the structure of SiO2/36° YX LiTaO3 will confine the acoustic wave energy in SiO2 thin-film, which contributes well to improvement of the mass loading sensitivity. The CrypA synthesized from vanillyl alcohol by a double trimerisation method was dropped onto the wave propagation path of the sensing device, and the adsorption to methane gas molecules by supramolecular interactions in CrypA modulates the acoustic wave propagation, and the corresponding frequency shifts were connected as the sensing signal. A theoretical analysis was performed to extract the coupling of modes for sensing devices simulation. Also, the temperature self-compensation of the Love wave devices was also achieved by using reverse polarity of the temperature coefficient in each media in the waveguide structure. The developed CrypA coated Love wave sensing device was connected into the differential oscillation loop, and the corresponding gas sensitive characterization was investigated. High sensitivity, fast response, and excellent temperature stability were successfully achieved.

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Lie symmetries of Benjamin-Ono equation

Mathematical Biosciences and Engineering ◽

10.3934/mbe.2021466 ◽

2021 ◽

Vol 18 (6) ◽

pp. 9496-9510

Author(s):

Weidong Zhao ◽

◽

Mobeen Munir ◽

Ghulam Murtaza ◽

Muhammad Athar ◽

...

Keyword(s):

Differential Equation ◽

Recent Work ◽

Present Article ◽

Internal Waves ◽

Laws Of Nature ◽

Symmetry Algebra ◽

Lie Symmetry ◽

Symmetry Analysis ◽

One Dimension ◽

Lie Symmetry Analysis

<abstract><p>Lie Symmetry analysis is often used to exploit the conservative laws of nature and solve or at least reduce the order of differential equation. One dimension internal waves are best described by Benjamin-Ono equation which is a nonlinear partial integro-differential equation. Present article focuses on the Lie symmetry analysis of this equation because of its importance. Lie symmetry analysis of this equation has been done but there are still some gaps and errors in the recent work. We claim that the symmetry algebra is of five dimensional. We reduce the model and solve it. We give its solution and analyze them graphically.</p></abstract>

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