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Xu R, Jiang Z, Yang Q, Bloino J, Biczysko M. Harmonic and anharmonic vibrational computations for biomolecular building blocks: Benchmarking DFT and basis sets by theoretical and experimental IR spectrum of glycine conformers. J Comput Chem 2024. [PMID: 38682874 DOI: 10.1002/jcc.27377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 04/01/2024] [Accepted: 04/02/2024] [Indexed: 05/01/2024]
Abstract
Advanced vibrational spectroscopic experiments have reached a level of sophistication that can only be matched by numerical simulations in order to provide an unequivocal analysis, a crucial step to understand the structure-function relationship of biomolecules. While density functional theory (DFT) has become the standard method when targeting medium-size or larger systems, the problem of its reliability and accuracy are well-known and have been abundantly documented. To establish a reliable computational protocol, especially when accuracy is critical, a tailored benchmark is usually required. This is generally done over a short list of known candidates, with the basis set often fixed a priori. In this work, we present a systematic study of the performance of DFT-based hybrid and double-hybrid functionals in the prediction of vibrational energies and infrared intensities at the harmonic level and beyond, considering anharmonic effects through vibrational perturbation theory at the second order. The study is performed for the six-lowest energy glycine conformers, utilizing available "state-of-the-art" accurate theoretical and experimental data as reference. Focusing on the most intense fundamental vibrations in the mid-infrared range of glycine conformers, the role of the basis sets is also investigated considering the balance between computational cost and accuracy. Targeting larger systems, a broad range of hybrid schemes with different computational costs is also tested.
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Affiliation(s)
- Ruiqin Xu
- Department of Physics, College of Sciences, Shanghai University, Shanghai, China
| | | | - Qin Yang
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Science, Prague, Czechia
| | - Julien Bloino
- Classe di Scienze, Scuola Normale Superiore, Pisa, Italy
| | - Malgorzata Biczysko
- Department of Physics, College of Sciences, Shanghai University, Shanghai, China
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2
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Zhao B, Zhang Y, Zhang S, Hu T, Guo Y. Multifactorial interaction of selenium, iron, xylose, and glycine on cordycepin metabolism in Cordyceps militaris. Appl Microbiol Biotechnol 2023; 107:7403-7416. [PMID: 37773218 DOI: 10.1007/s00253-023-12792-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/08/2023] [Accepted: 09/12/2023] [Indexed: 10/01/2023]
Abstract
Cordycepin, a nucleoside analog, is the main antioxidative and antimicrobial substance in Cordyceps militaris. To improve the metabolism of cordycepin, carbon sources, nitrogen sources, trace elements, and precursors were studied by single factor, Plackett-Burman, and central composite designs in C. militaris mycelial fermentation. Under the regulation of the multifactorial interactions of selenite, ferrous chloride, xylose, and glycine, cordycepin production was increased by 5.2-fold compared with the control. The gene expression of hexokinase, ATP phosphoribosyltransferase, adenylosuccinate synthetase, and cns1-3 in the glycolysis, pentose phosphate, and adenosine synthesis pathways were increased by 3.2-7.5 times due to multifactorial interactions, while the gene expression of histidine biosynthesis trifunctional protein and histidinol-phosphate aminotransferase in histidine synthesis pathway were decreased by 23.4%-56.2%. Increasing with cordycepin production, glucose uptake was accelerated, mycelia growth was inhibited, and the cell wall was damaged. Selenomethionine (SeMet), selenocysteine (SeCys), and selenium nanoparticles (SeNPs) were the major Se species in C. militaris mycelia. This study provides a new insight for promoting cordycepin production by regulating glycolysis, pentose phosphate, and histidine metabolism. KEY POINTS: • Cordycepin production in the CCDmax group was 5.2-fold than that of the control. • Glucose uptake of the CCDmax group was accelerated and cell wall was damaged. • The metabolic flux was concentrated to the cordycepin synthesis pathway.
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Affiliation(s)
- Bingjie Zhao
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
| | - Yong Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
| | - Sasa Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China
| | - Ting Hu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Yanbin Guo
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing, 100193, China.
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3
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Mandelli G, Corneo L, Aieta C. Coupled Cluster Semiclassical Estimates of Experimental Reaction Rates: The Interconversion of Glycine Conformer VIp to Ip. J Phys Chem Lett 2023; 14:9996-10002. [PMID: 37906174 PMCID: PMC10641884 DOI: 10.1021/acs.jpclett.3c02560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/02/2023]
Abstract
We apply the full-dimensional Semiclassical Transition State Theory (SCTST) to estimate the rate constant of glycine molecule interconversion between the VIp and Ip conformers. We have reached an electronic structure accuracy up to the explicitly correlated Coupled Cluster method (CCSD(T)-F12b/cc-pVDZ-F12) thanks to our parallel implementation. The reaction has been experimentally investigated in the literature and is known to proceed by quantum mechanical tunneling. The SCTST rates improve over other theoretical methods, and our results align with the experimental measurements, thus confirming the accuracy of the fully coupled anharmonic semiclassical tunneling treatment, providing that the level of electronic structure theory gives a reliable estimate of the reaction barrier height and shape. The comparison with experimental half-life times supports the validity of SCTST for glycine VIp-Ip conformer conversion in the cryogenic temperature range, where this theory is usually not considered applicable due to the onset of the deep tunneling regime.
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Affiliation(s)
- Giacomo Mandelli
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, Milano 20133, Italy
| | - Luca Corneo
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, Milano 20133, Italy
| | - Chiara Aieta
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, Milano 20133, Italy
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4
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Barone V, Di Grande S, Puzzarini C. Toward Accurate yet Effective Computations of Rotational Spectroscopy Parameters for Biomolecule Building Blocks. MOLECULES (BASEL, SWITZERLAND) 2023; 28:molecules28020913. [PMID: 36677970 PMCID: PMC9863398 DOI: 10.3390/molecules28020913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 01/01/2023] [Accepted: 01/12/2023] [Indexed: 01/19/2023]
Abstract
The interplay of high-resolution rotational spectroscopy and quantum-chemical computations plays an invaluable role in the investigation of biomolecule building blocks in the gas phase. However, quantum-chemical methods suffer from unfavorable scaling with the dimension of the system under consideration. While a complete characterization of flexible systems requires an elaborate multi-step strategy, in this work, we demonstrate that the accuracy obtained by quantum-chemical composite approaches in the prediction of rotational spectroscopy parameters can be approached by a model based on density functional theory. Glycine and serine are employed to demonstrate that, despite its limited cost, such a model is able to predict rotational constants with an accuracy of 0.3% or better, thus paving the way toward the accurate characterization of larger flexible building blocks of biomolecules.
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Affiliation(s)
- Vincenzo Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-50126 Pisa, Italy
- Correspondence: (V.B.); (C.P.)
| | - Silvia Di Grande
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-50126 Pisa, Italy
- Scuola Superiore Meridionale, Largo San Marcellino 10, I-80138 Napoli, Italy
| | - Cristina Puzzarini
- Rotational and Computational Spectroscopy Lab, Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via F. Selmi 2, I-40126 Bologna, Italy
- Correspondence: (V.B.); (C.P.)
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5
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Louis H, Charlie DE, Amodu IO, Benjamin I, Gber TE, Agwamba EC, Adeyinka AS. Probing the Reactions of Thiourea (CH 4N 2S) with Metals (X = Au, Hf, Hg, Ir, Os, W, Pt, and Re) Anchored on Fullerene Surfaces (C 59X). ACS OMEGA 2022; 7:35118-35135. [PMID: 36211036 PMCID: PMC9535727 DOI: 10.1021/acsomega.2c04044] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 08/08/2022] [Indexed: 05/21/2023]
Abstract
Upon various investigations conducted in search for a nanosensor material with the best sensing performance, the need to explore these materials cannot be overemphasized as materials associated with best sensing attributes are of vast interest to researchers. Hence, there is a need to investigate the adsorption performances of various metal-doped fullerene surfaces: C59Au, C59Hf, C59Hg, C59Ir, C59Os, C59Pt, C59Re, and C59W on thiourea [SC(NH2)2] molecule using first-principles density functional theory computation. Comparative adsorption study has been carried out on various adsorption models of four functionals, M06-2X, M062X-D3, PBE0-D3, and ωB97XD, and two double-hybrid (DH) functionals, DSDPBEP86 and PBE0DH, as reference at Gen/def2svp/LanL2DZ. The visual study of weak interactions such as quantum theory of atoms in molecule analysis and noncovalent interaction analysis has been invoked to ascertain these results, and hence we arrived at a conclusive scientific report. In all cases, the weak adsorption observed is best described as physisorption phenomena, and CH4N2S@C59Pt complex exhibits better sensing attributes than its studied counterparts in the interactions between thiourea molecule and transition metal-doped fullerene surfaces. Also, in the comparative adsorption study, DH density functionals show better performance in estimating the adsorption energies due to their reduced mean absolute deviation (MAD) and root-mean-square deviation (RMSD) values of (MAD = 1.0305, RMSD = 1.6277) and (MAD = 0.9965, RMSD = 1.6101) in DSDPBEP86 and PBE0DH, respectively.
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Affiliation(s)
- Hitler Louis
- Computational
and Bio-Simulation Research Group, University
of Calabar, Calabar 540221, Nigeria
- Department
of Pure and Applied Chemistry, Faculty of Physical Sciences, University of Calabar, Calabar 540221, Nigeria
| | - Destiny E. Charlie
- Computational
and Bio-Simulation Research Group, University
of Calabar, Calabar 540221, Nigeria
- Department
of Pure and Applied Chemistry, Faculty of Physical Sciences, University of Calabar, Calabar 540221, Nigeria
| | - Ismail O. Amodu
- Computational
and Bio-Simulation Research Group, University
of Calabar, Calabar 540221, Nigeria
- Department
of Mathematics, Faculty of Physical Sciences, University of Calabar, Calabar 540221, Nigeria
| | - Innocent Benjamin
- Computational
and Bio-Simulation Research Group, University
of Calabar, Calabar 540221, Nigeria
| | - Terkumbur E. Gber
- Computational
and Bio-Simulation Research Group, University
of Calabar, Calabar 540221, Nigeria
- Department
of Pure and Applied Chemistry, Faculty of Physical Sciences, University of Calabar, Calabar 540221, Nigeria
| | - Ernest C. Agwamba
- Computational
and Bio-Simulation Research Group, University
of Calabar, Calabar 540221, Nigeria
| | - Adedapo S. Adeyinka
- Department
of Chemical Sciences, University of Johannesburg, Johannesburg 2006, South Africa
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6
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Bertolini S, Jacob T. Elucidating active sites and decomposition mechanisms for oxythiomolybdate clusters (Mo
2
O
2
S
x
, x = 6;8) as catalyzers for hydrogen evolution reactions. ELECTROCHEMICAL SCIENCE ADVANCES 2022. [DOI: 10.1002/elsa.202100088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Samuel Bertolini
- Institute of Electrochemistry Faculty of Natural Sciences Ulm University Albert‐Einstein‐Allee 47 Ulm Germany
| | - Timo Jacob
- Institute of Electrochemistry Faculty of Natural Sciences Ulm University Albert‐Einstein‐Allee 47 Ulm Germany
- Helmholtz‐Institute Ulm (HIU), Electrochemical Energy Storage Ulm Germany
- Karlsruhe Institute of Technology (KIT) Karlsruhe Germany
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7
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DFT study on the synthesis of trifluoroacetophenone from palladium complex L nPd(Ph)CF 3 (L n = Xantphos or DtBPF) and CO. J Mol Model 2022; 28:48. [PMID: 35083574 DOI: 10.1007/s00894-022-05030-0] [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: 11/18/2020] [Accepted: 01/17/2022] [Indexed: 10/19/2022]
Abstract
The carbonylative trifluoromethylation reaction mechanism of palladium complex LnPd(Ph)CF3 (Ln = Xantphos or DtBPF) and CO to synthesize trifluoroacetophenone was calculated using the density functional theory B3LYP method. In this paper, we conducted a computational study on the competition mechanism of two different products trifluorotoluene and trifluoroacetophenone. The calculation result reveals (1) CO insertion and reduction-elimination are two key steps in palladium-catalyzed reactions; (2) for the palladium complex (Xantphos)Pd(Ph)CF3, the resulting product trifluoroacetyl has a lower activation energy and higher reactivity; and (3) for the metal palladium ligand DtBPF, the small energy difference between the two products indicates that the stereoselectivity of the product is relatively poor. The computational research results in this paper provide a good supplement and effective explanation to the experimental phenomenon of Domino et al. (Organometallics 39:688-697, 2020).
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8
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Zhao Y, Huo M, Zhou H. DFT study on the gold(I)-catalyzed cycloaddition and rearrangement reactions of allene-containing allylic silyl ether. J Mol Model 2021; 28:25. [PMID: 34970719 DOI: 10.1007/s00894-021-05004-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 12/14/2021] [Indexed: 01/14/2023]
Abstract
The DFT calculation at the B3LYP/B3LYP-D3(BJ) level was carried out to explore the reaction mechanism of the synthesis of spirocyclo[4,5]decane skeleton by gold-catalyzed allenyl compounds. The more accurate energy under the CH3CN solvent in the experiment is calculated by the single-point energy of the SMD model. Computational studies have shown that the reaction consists of three main steps: intramolecular cycloaddition of the end group carbon atoms of allenyl and vinyl groups, the semipinacol rearrangement process in which the four-membered ring is reconstructed into the five-membered ring, the elimination reaction releases the catalyst and obtains the product. The calculation results show that Zheng et al. reported that the gold-catalyzed synthesis reaction can easily occur under the experimental conditions due to its low activation free energy (12.07-15.49 kcal/mol). Furthermore, it was found that the MOMO(CH2)2 substituent has higher reactivity than the corresponding reactant of the phenyl substituent.
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Affiliation(s)
- YaMei Zhao
- School of Environmental and Chemical Engineering, Xi'an Polytechnic University, Xi'an, 710048, Shaanxi, China.
| | - MengDan Huo
- School of Environmental and Chemical Engineering, Xi'an Polytechnic University, Xi'an, 710048, Shaanxi, China
| | - HongJi Zhou
- School of Environmental and Chemical Engineering, Xi'an Polytechnic University, Xi'an, 710048, Shaanxi, China
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9
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Wang P, Shu C, Ye H, Biczysko M. Structural and Energetic Properties of Amino Acids and Peptides Benchmarked by Accurate Theoretical and Experimental Data. J Phys Chem A 2021; 125:9826-9837. [PMID: 34752094 DOI: 10.1021/acs.jpca.1c06504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Structural, energetic, and spectroscopic data derived in this work aim at the setup of an "experimentally validated" database for amino acids and polypeptides conformers. First, the "cheap" composite scheme (ChS, CCSD(T)/(CBS+CV)MP2) is tested for evaluation of conformational energies of all eight stable conformers of glycine, by comparing to the more accurate CCSD(T)/CBS+CV computations (Phys. Chem. Chem. Phys. 2013, 15, 10094-10111 and J Mol. Model. 2020, 26, 129). The recently proposed jun-ChS (J. Chem. Theory and Comput. 2020, 16, 988-1006), employing the jun-cc-pVnZ basis set family for CCSD(T) computations and CBS extrapolation, yields conformational energies accurate to 0.2 kJ·mol-1, at reduced computational cost with respect to aug-ChS employing aug-cc-pVnZ basis sets. The jun-ChS composite scheme is further applied to derive conformational energies for three dipeptide analogues Ac-Gly-NH2, Ac-Ala-NH2, and Gly-Gly. Finally, dipeptide conformational energies and semiexperimental equilibrium rotational constants along with the CCSD(T)/(CBS+CV)MP2 structural parameters (J. Phys. Chem. Lett. 2014, 5, 534-540) stand as the reference for benchmarking of selected density functional methodologies. The double-hybrid functionals B2-PLYP-D3(BJ) and DSD-PBEP86, perform best for structural and energetic characterization of all dipeptide analogues. From hybrid functionals CAM-B3LYP-D3(BJ) and ωB97X-D3(BJ) represent promising methods applicable for larger peptide-based systems for which computations with double-hybrid functionals are not feasible.
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Affiliation(s)
- Ping Wang
- International Centre for Quantum and Molecular Structures, Physics Department, College of Science, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Chong Shu
- International Centre for Quantum and Molecular Structures, Physics Department, College of Science, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Hexu Ye
- International Centre for Quantum and Molecular Structures, Physics Department, College of Science, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Malgorzata Biczysko
- International Centre for Quantum and Molecular Structures, Physics Department, College of Science, Shanghai University, 99 Shangda Road, Shanghai 200444, China
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10
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Sheng M, Silvestrini F, Biczysko M, Puzzarini C. Structural and Vibrational Properties of Amino Acids from Composite Schemes and Double-Hybrid DFT: Hydrogen Bonding in Serine as a Test Case. J Phys Chem A 2021; 125:9099-9114. [PMID: 34623165 DOI: 10.1021/acs.jpca.1c06993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The structures, relative stabilities, and vibrational wavenumbers of the two most stable conformers of serine, stabilized by the O-H···N, O-H···O═C and N-H···O-H intramolecular hydrogen bonds, have been evaluated by means of state-of-the-art composite schemes based on coupled-cluster (CC) theory. The so-called "cheap" composite approach (CCSD(T)/(CBS+CV)MP2) allowed determination of accurate equilibrium structures and harmonic vibrational wavenumbers, also pointing out significant corrections beyond the CCSD(T)/cc-pVTZ level. These accurate results stand as a reference for benchmarking selected hybrid and double-hybrid, dispersion-corrected DFT functionals. B2PLYP-D3 and DSDPBEP86 in conjunction with a triple-ζ basis set have been confirmed as effective methodologies for structural and spectroscopic studies of medium-sized flexible biomolecules, also showing intramolecular hydrogen bonding. These best performing double-hybrid functionals have been employed to simulate IR spectra by means of vibrational perturbation theory, also considering hybrid CC/DFT schemes. The best overall agreement with experiment, with mean absolute error of 8 cm-1, has been obtained by combining CCSD(T)/(CBS+CV)MP2 harmonic wavenumbers with B2PLYP-D3/maug-cc-pVTZ anharmonic corrections. Finally, a composite scheme entirely based on CCSD(T) calculations (CCSD(T)/CBS+CV) has been employed for energetics, further confirming that serine II is the most stable conformer, also when zero-point vibrational energy corrections are included.
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Affiliation(s)
- Mingzhu Sheng
- International Centre for Quantum and Molecular Structures, Physics Department, Shanghai University, 99 Shangda Road, Shanghai, 200444, China
| | - Filippo Silvestrini
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via F. Selmi 2, 40126 Bologna, Italy
| | - Malgorzata Biczysko
- International Centre for Quantum and Molecular Structures, Physics Department, Shanghai University, 99 Shangda Road, Shanghai, 200444, China
| | - Cristina Puzzarini
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via F. Selmi 2, 40126 Bologna, Italy
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11
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Grabska J, Beć KB, Ozaki Y, Huck CW. Anharmonic DFT Study of Near-Infrared Spectra of Caffeine: Vibrational Analysis of the Second Overtones and Ternary Combinations. Molecules 2021; 26:molecules26175212. [PMID: 34500645 PMCID: PMC8433751 DOI: 10.3390/molecules26175212] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/23/2021] [Accepted: 08/24/2021] [Indexed: 11/16/2022] Open
Abstract
Anharmonic quantum chemical calculations were employed to simulate and interpret a near-infrared (NIR) spectrum of caffeine. First and second overtones, as well as binary and ternary combination bands, were obtained, accurately reproducing the lineshape of the experimental spectrum in the region of 10,000–4000 cm−1 (1000–2500 nm). The calculations enabled performing a detailed analysis of NIR spectra of caffeine, including weak bands due to the second overtones and ternary combinations. A highly convoluted nature of NIR spectrum of caffeine was unveiled, with numerous overlapping bands found beneath the observed spectral lineshape. To properly reflect that intrinsic complexity, the band assignments were provided in the form of heat maps presenting the contributions to the NIR spectrum from various kinds of vibrational transitions. These contributions were also quantitatively assessed in terms of the integral intensities. It was found that the combination bands provide the decisively dominant contributions to the NIR spectrum of caffeine. The first overtones gain significant importance between 6500–5500 cm−1, while the second overtones are meaningful in the higher wavenumber regions, particularly in the 10,000–7000 cm−1 region. The obtained detailed band assignments enabled deep interpretation of the absorption regions of caffeine identified in the literature as meaningful for analytical applications of NIR spectroscopy focused on quantitative analysis of caffeine content in drugs and natural products.
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Affiliation(s)
- Justyna Grabska
- CCB—Center for Chemistry and Biomedicine, Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 80/82, 6020 Innsbruck, Austria; (K.B.B.); (C.W.H.)
- Correspondence:
| | - Krzysztof B. Beć
- CCB—Center for Chemistry and Biomedicine, Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 80/82, 6020 Innsbruck, Austria; (K.B.B.); (C.W.H.)
| | - Yukihiro Ozaki
- School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda 669-1337, Hyogo, Japan;
- Toyota Physical and Chemical Research Institute, Yokomichi, Nagakute 480-1192, Aichi, Japan
| | - Christian W. Huck
- CCB—Center for Chemistry and Biomedicine, Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 80/82, 6020 Innsbruck, Austria; (K.B.B.); (C.W.H.)
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12
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Structural Water Stabilizes Protein Motifs in Liquid Protein Phase: The Folding Mechanism of Short β-Sheets Coupled to Phase Transition. Int J Mol Sci 2021; 22:ijms22168595. [PMID: 34445303 PMCID: PMC8395295 DOI: 10.3390/ijms22168595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/03/2021] [Accepted: 08/05/2021] [Indexed: 11/16/2022] Open
Abstract
Macromolecular associates, such as membraneless organelles or lipid-protein assemblies, provide a hydrophobic environment, i.e., a liquid protein phase (LP), where folding preferences can be drastically altered. LP as well as the associated phase change from water (W) is an intriguing phenomenon related to numerous biological processes and also possesses potential in nanotechnological applications. However, the energetic effects of a hydrophobic yet water-containing environment on protein folding are poorly understood. Here, we focus on small β-sheets, the key motifs of proteins, undergoing structural changes in liquid–liquid phase separation (LLPS) and also model the mechanism of energy-coupled unfolding, e.g., in proteases, during W → LP transition. Due to the importance of the accurate description for hydrogen bonding patterns, the employed models were studied by using quantum mechanical calculations. The results demonstrate that unfolding is energetically less favored in LP by ~0.3–0.5 kcal·mol−1 per residue in which the difference further increased by the presence of explicit structural water molecules, where the folded state was preferred by ~1.2–2.3 kcal·mol−1 per residue relative to that in W. Energetics at the LP/W interfaces was also addressed by theoretical isodesmic reactions. While the models predict folded state preference in LP, the unfolding from LP to W renders the process highly favorable since the unfolded end state has >1 kcal·mol−1 per residue excess stabilization.
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13
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Barone V, Puzzarini C, Mancini G. Integration of theory, simulation, artificial intelligence and virtual reality: a four-pillar approach for reconciling accuracy and interpretability in computational spectroscopy. Phys Chem Chem Phys 2021; 23:17079-17096. [PMID: 34346437 DOI: 10.1039/d1cp02507d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The established pillars of computational spectroscopy are theory and computer based simulations. Recently, artificial intelligence and virtual reality are becoming the third and fourth pillars of an integrated strategy for the investigation of complex phenomena. The main goal of the present contribution is the description of some new perspectives for computational spectroscopy, in the framework of a strategy in which computational methodologies at the state of the art, high-performance computing, artificial intelligence and virtual reality tools are integrated with the aim of improving research throughput and achieving goals otherwise not possible. Some of the key tools (e.g., continuous molecular perception model and virtual multifrequency spectrometer) and theoretical developments (e.g., non-periodic boundaries, joint variational-perturbative models) are shortly sketched and their application illustrated by means of representative case studies taken from recent work by the authors. Some of the results presented are already well beyond the state of the art in the field of computational spectroscopy, thereby also providing a proof of concept for other research fields.
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Affiliation(s)
- Vincenzo Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa, Italy.
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14
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Barone V, Alessandrini S, Biczysko M, Cheeseman JR, Clary DC, McCoy AB, DiRisio RJ, Neese F, Melosso M, Puzzarini C. Computational molecular spectroscopy. ACTA ACUST UNITED AC 2021. [DOI: 10.1038/s43586-021-00034-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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