1
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Schweitzer-Stenner R. The relevance of short peptides for an understanding of unfolded and intrinsically disordered proteins. Phys Chem Chem Phys 2023; 25:11908-11933. [PMID: 37096579 DOI: 10.1039/d3cp00483j] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
Abstract
Over the last thirty years the unfolded state of proteins has attracted considerable interest owing to the discovery of intrinsically disordered proteins which perform a plethora of functions despite resembling unfolded proteins to a significant extent. Research on both, unfolded and disordered proteins has revealed that their conformational properties can deviate locally from random coil behavior. In this context results from work on short oligopeptides suggest that individual amino acid residues sample the sterically allowed fraction of the Ramachandran plot to a different extent. Alanine has been found to exhibit a peculiarity in that it has a very high propensity for adopting polyproline II like conformations. This Perspectives article reviews work on short peptides aimed at exploring the Ramachandran distributions of amino acid residues in different contexts with experimental and computational means. Based on the thus provided overview the article discussed to what extent short peptides can serve as tools for exploring unfolded and disordered proteins and as benchmarks for the development of a molecular dynamics force field.
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2
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Krevert CS, Gunkel L, Haese C, Hunger J. Ion-specific binding of cations to the carboxylate and of anions to the amide of alanylalanine. Commun Chem 2022; 5:173. [PMID: 36697920 PMCID: PMC9814750 DOI: 10.1038/s42004-022-00789-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 11/30/2022] [Indexed: 12/24/2022] Open
Abstract
Studies of ion-specific effects on oligopeptides have aided our understanding of Hofmeister effects on proteins, yet the use of different model peptides and different experimental sensitivities have led to conflicting conclusions. To resolve these controversies, we study a small model peptide, L-Alanyl-L-alanine (2Ala), carrying all fundamental chemical protein motifs: C-terminus, amide bond, and N-terminus. We elucidate the effect of GdmCl, LiCl, KCl, KI, and KSCN by combining dielectric relaxation, nuclear magnetic resonance (1H-NMR), and (two-dimensional) infrared spectroscopy. Our dielectric results show that all ions reduce the rotational mobility of 2Ala, yet the magnitude of the reduction is larger for denaturing cations than for anions. The NMR chemical shifts of the amide group are particularly sensitive to denaturing anions, indicative of anion-amide interactions. Infrared experiments reveal that LiCl alters the spectral homogeneity and dynamics of the carboxylate, but not the amide group. Interaction of LiCl with the negatively charged pole of 2Ala, the COO- group, can explain the marked cationic effect on dipolar rotation, while interaction of anions between the poles, at the amide, only weakly perturbs dipolar dynamics. As such, our results provide a unifying view on ions' preferential interaction sites at 2Ala and help rationalize Hofmeister effects on proteins.
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Affiliation(s)
- Carola Sophie Krevert
- grid.419547.a0000 0001 1010 1663Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Lucas Gunkel
- grid.419547.a0000 0001 1010 1663Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Constantin Haese
- grid.419547.a0000 0001 1010 1663Department of Molecular Electronics, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Johannes Hunger
- grid.419547.a0000 0001 1010 1663Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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3
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Hassan I, Ferraro F, Imhof P. Effect of the Hydration Shell on the Carbonyl Vibration in the Ala-Leu-Ala-Leu Peptide. Molecules 2021; 26:2148. [PMID: 33917998 PMCID: PMC8068333 DOI: 10.3390/molecules26082148] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/30/2021] [Accepted: 03/30/2021] [Indexed: 11/16/2022] Open
Abstract
The vibrational spectrum of the Ala-Leu-Ala-Leu peptide in solution, computed from first-principles simulations, shows a prominent band in the amide I region that is assigned to stretching of carbonyl groups. Close inspection reveals combined but slightly different contributions by the three carbonyl groups of the peptide. The shift in their exact vibrational signature is in agreement with the different probabilities of these groups to form hydrogen bonds with the solvent. The central carbonyl group has a hydrogen bond probability intermediate to the other two groups due to interchanges between different hydrogen-bonded states. Analysis of the interaction energies of individual water molecules with that group shows that shifts in its frequency are directly related to the interactions with the water molecules in the first hydration shell. The interaction strength is well correlated with the hydrogen bond distance and hydrogen bond angle, though there is no perfect match, allowing geometrical criteria for hydrogen bonds to be used as long as the sampling is sufficient to consider averages. The hydrogen bond state of a carbonyl group can therefore serve as an indicator of the solvent's effect on the vibrational frequency.
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Affiliation(s)
- Irtaza Hassan
- Institute for Theoretical Physics, Freie Universtiät Berlin, Arnimallee 14, 14195 Berlin, Germany;
| | - Federica Ferraro
- Computer Chemistry Center, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Nägelsbachstrasse 25, 91052 Erlangen, Germany;
| | - Petra Imhof
- Institute for Theoretical Physics, Freie Universtiät Berlin, Arnimallee 14, 14195 Berlin, Germany;
- Computer Chemistry Center, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Nägelsbachstrasse 25, 91052 Erlangen, Germany;
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4
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Kirchner B, Blasius J, Esser L, Reckien W. Predicting Vibrational Spectroscopy for Flexible Molecules and Molecules with Non‐Idle Environments. ADVANCED THEORY AND SIMULATIONS 2020. [DOI: 10.1002/adts.202000223] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Barbara Kirchner
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Jan Blasius
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Lars Esser
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Werner Reckien
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
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5
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Hassan I, Donati L, Stensitzki T, Keller BG, Heyne K, Imhof P. The vibrational spectrum of the hydrated alanine-leucine peptide in the amide region from IR experiments and first principles calculations. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2018.03.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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6
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Gregori B, Guidoni L, Crestoni ME, de Oliveira P, Houée-Levin C, Scuderi D. One-Electron Oxidation of Methionine-Containing Dipeptides of Reverse Sequence: Sulfur versus Sulfoxide Characterized by IRMPD Spectroscopy and Static and Dynamics DFT Simulations. J Phys Chem B 2017; 121:2083-2094. [DOI: 10.1021/acs.jpcb.6b12638] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
| | - Leonardo Guidoni
- Dipartimento
di Scienza Fisiche e Chimiche, Università degli Studi dell’Aquila, Via Vetoio 2, Coppito, L’Aquila I-64100, Italy
| | | | - Pedro de Oliveira
- Laboratoire
de Chimie Physique, Université Paris Sud, Bat. 349, CNRS UMR8000, 15 rue Georges Clemenceau, Orsay Cedex 91405, France
| | - Chantal Houée-Levin
- Laboratoire
de Chimie Physique, Université Paris Sud, Bat. 349, CNRS UMR8000, 15 rue Georges Clemenceau, Orsay Cedex 91405, France
| | - Debora Scuderi
- Laboratoire
de Chimie Physique, Université Paris Sud, Bat. 349, CNRS UMR8000, 15 rue Georges Clemenceau, Orsay Cedex 91405, France
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7
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Vitale V, Dziedzic J, Dubois SMM, Fangohr H, Skylaris CK. Anharmonic Infrared Spectroscopy through the Fourier Transform of Time Correlation Function Formalism in ONETEP. J Chem Theory Comput 2016; 11:3321-32. [PMID: 26575766 DOI: 10.1021/acs.jctc.5b00391] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Density functional theory molecular dynamics (DFT-MD) provides an efficient framework for accurately computing several types of spectra. The major benefit of DFT-MD approaches lies in the ability to naturally take into account the effects of temperature and anharmonicity, without having to introduce any ad hoc or a posteriori corrections. Consequently, computational spectroscopy based on DFT-MD approaches plays a pivotal role in the understanding and assignment of experimental peaks and bands at finite temperature, particularly in the case of floppy molecules. Linear-scaling DFT methods can be used to study large and complex systems, such as peptides, DNA strands, amorphous solids, and molecules in solution. Here, we present the implementation of DFT-MD IR spectroscopy in the ONETEP linear-scaling code. In addition, two methods for partitioning the dipole moment within the ONETEP framework are presented. Dipole moment partitioning allows us to compute spectra of molecules in solution, which fully include the effects of the solvent, while at the same time removing the solvent contribution from the spectra.
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Affiliation(s)
- Valerio Vitale
- School of Chemistry, University of Southampton , Southampton, United Kingdom.,Institute of Complex Systems Simulation, University of Southampton , Southampton, United Kingdom
| | - Jacek Dziedzic
- School of Chemistry, University of Southampton , Southampton, United Kingdom.,Faculty of Applied Physics and Mathematics, Gdańsk University of Technology , Gdańsk, Poland
| | - Simon M-M Dubois
- Institut de la Matière Condenseée et des Nanosciences, Universitè Catholique de Louvain B-1348 Louvain-la-Neuve, Belgium
| | - Hans Fangohr
- Engineering and the Environment, University of Southampton , Southampton, United Kingdom.,Institute of Complex Systems Simulation, University of Southampton , Southampton, United Kingdom
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8
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Hanson-Heine MWD, Husseini FS, Hirst JD, Besley NA. Simulation of Two-Dimensional Infrared Spectroscopy of Peptides Using Localized Normal Modes. J Chem Theory Comput 2016; 12:1905-18. [DOI: 10.1021/acs.jctc.5b01198] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Fouad S. Husseini
- School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - Jonathan D. Hirst
- School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - Nicholas A. Besley
- School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
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9
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Mahé J, Jaeqx S, Rijs AM, Gaigeot MP. Can far-IR action spectroscopy combined with BOMD simulations be conformation selective? Phys Chem Chem Phys 2015; 17:25905-14. [DOI: 10.1039/c5cp01518a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The combination of conformation selective far-IR/UV double resonance spectroscopy with Born–Oppenheimer molecular dynamics (BOMD) simulations is presented here for the structural characterization of the Ac-Phe-Pro-NH2 peptide in the far-infrared spectral domain, i.e. for radiation below 800 cm−1.
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Affiliation(s)
- Jérôme Mahé
- LAMBE CNRS UMR8587
- Université d'Evry val d'Essonne
- 91025 Evry
- France
| | - Sander Jaeqx
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
| | - Anouk M. Rijs
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
| | - Marie-Pierre Gaigeot
- LAMBE CNRS UMR8587
- Université d'Evry val d'Essonne
- 91025 Evry
- France
- Institut Universitaire de France
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10
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Luber S, Iannuzzi M, Hutter J. Raman spectra from ab initio molecular dynamics and its application to liquid S-methyloxirane. J Chem Phys 2014; 141:094503. [DOI: 10.1063/1.4894425] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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11
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Jiang F, Han W, Wu YD. The intrinsic conformational features of amino acids from a protein coil library and their applications in force field development. Phys Chem Chem Phys 2013; 15:3413-28. [PMID: 23385383 DOI: 10.1039/c2cp43633g] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The local conformational (φ, ψ, χ) preferences of amino acid residues remain an active research area, which are important for the development of protein force fields. In this perspective article, we first summarize spectroscopic studies of alanine-based short peptides in aqueous solution. While most studies indicate a preference for the P(II) conformation in the unfolded state over α and β conformations, significant variations are also observed. A statistical analysis from various coil libraries of high-resolution protein structures is then summarized, which gives a more coherent view of the local conformational features. The φ, ψ, χ distributions of the 20 amino acids have been obtained from a protein coil library, considering both backbone and side-chain conformational preferences. The intrinsic side-chain χ(1) rotamer preference and χ(1)-dependent Ramachandran plot can be generally understood by combining the interaction of the side-chain Cγ/Oγ atom with two neighboring backbone peptide groups. Current all-atom force fields such as AMBER ff99sb-ILDN, ff03 and OPLS-AA/L do not reproduce these distributions well. A method has been developed by combining the φ, ψ plot of alanine with the influence of side-chain χ(1) rotamers to derive the local conformational features of various amino acids. It has been further applied to improve the OPLS-AA force field. The modified force field (OPLS-AA/C) reproduces experimental (3)J coupling constants for various short peptides quite well. It also better reproduces the temperature-dependence of the helix-coil transition for alanine-based peptides. The new force field can fold a series of peptides and proteins with various secondary structures to their experimental structures. MD simulations of several globular proteins using the improved force field give significantly less deviation (RMSD) to experimental structures. The results indicate that the local conformational features from coil libraries are valuable for the development of balanced protein force fields.
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Affiliation(s)
- Fan Jiang
- Laboratory of Computational Chemistry and Drug Design, Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
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12
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Farag MH, Zúñiga J, Requena A, Bastida A. Instantaneous normal mode analysis of the vibrational relaxation of the amide I mode of alanine dipeptide in water. J Chem Phys 2013; 138:205102. [DOI: 10.1063/1.4805086] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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13
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Simon A, Spiegelman F. Water clusters adsorbed on polycyclic aromatic hydrocarbons: Energetics and conformational dynamics. J Chem Phys 2013; 138:194309. [DOI: 10.1063/1.4805015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Lilienfeld OAV. Force correcting atom centred potentials for generalised gradient approximated density functional theory: Approaching hybrid functional accuracy for geometries and harmonic frequencies in small chlorofluorocarbons. Mol Phys 2013. [DOI: 10.1080/00268976.2013.793834] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- O. Anatole von Lilienfeld
- Argonne Leadership Computing Facility, Argonne National Laboratory , Argonne, IL, 60439, USA
- Department of Chemistry, University of Basel , Basel, Klingelbergstr, 80, 4056, Switzerland
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15
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Toal S, Meral D, Verbaro D, Urbanc B, Schweitzer-Stenner R. pH-Independence of trialanine and the effects of termini blocking in short peptides: a combined vibrational, NMR, UVCD, and molecular dynamics study. J Phys Chem B 2013; 117:3689-706. [PMID: 23448349 DOI: 10.1021/jp310466b] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Several lines of evidence now well establish that unfolded peptides in general, and alanine in specific, have an intrinsic preference for the polyproline II (pPII) conformation. Investigation of local order in the unfolded state is, however, complicated by experimental limitations and the inherent dynamics of the system, which has in some cases yielded inconsistent results from different types of experiments. One method of studying these systems is the use of short model peptides, and specifically short alanine peptides, known for predominantly sampling pPII structure in aqueous solution. Recently, He et al. ( J. Am. Chem. Soc. 2012 , 134 , 1571 - 1576 ) proposed that unblocked tripeptides may not be suitable models for studying conformational propensities in unfolded peptides due to the presence of end effect, that is, electrostatic interactions between investigated amino acid residues and terminal charges. To determine whether changing the protonation states of the N- and C-termini influence the conformational manifold of the central amino acid residue in tripeptides, we have examined the pH-dependence of unblocked trialanine and the conformational preferences of alanine in the alanine dipeptide. To this end, we measured and globally analyzed amide I' band profiles and NMR J-coupling constants. We described conformational distributions as the superposition of two-dimensional Gaussian distributions assignable to specific subspaces of the Ramachandran plot. Results show that the conformational ensemble of trialanine as a whole, and the pPII content (χpPII = 0.84) in particular, remains practically unaffected by changing the protonation state. We found that compared to trialanine, the alanine dipeptide has slightly lower pPII content (χpPII = 0.74) and an ensemble more reminiscent of the unblocked Gly-Ala-Gly model peptide. In addition, a two-state thermodynamic analysis of the conformational sensitive Δε(T) and (3)J(H(N)H(α))(T) data obtained from electronic circular dichroism and H NMR spectra indicate that the free energy landscape of trialanine is similar in all protonation states. MD simulations for the investigated peptides corroborate this notion and show further that the hydration shell around unblocked trialanine is unaffected by the protonation/deprotonation of the C-terminal group. In contrast, the alanine dipeptide shows a reduced water density around the central residue as well as a less ordered hydration shell, which decreases the pPII propensity and reduces the lifetime of sampled conformations.
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Affiliation(s)
- Siobhan Toal
- Department of Chemistry, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania 19104, USA
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16
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Mirkin NG, Krimm S. Water interaction differences determine the relative energetic stability of the polyproline II conformation of the alanine dipeptide in aqueous environments. Biopolymers 2012; 97:789-94. [DOI: 10.1002/bip.22064] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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17
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Bouteiller Y, Poully JC, Grégoire G. Evaluation of polarizable continuum model for the prediction of vibrational frequencies of biomimetic molecules in solution. COMPUT THEOR CHEM 2011. [DOI: 10.1016/j.comptc.2011.03.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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18
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Ingrosso F, Monard G, Hamdi Farag M, Bastida A, Ruiz-López MF. Importance of Polarization and Charge Transfer Effects to Model the Infrared Spectra of Peptides in Solution. J Chem Theory Comput 2011; 7:1840-9. [DOI: 10.1021/ct2000588] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Francesca Ingrosso
- Equipe de Chimie et Biochimie Théoriques, UMR 7565 SRSMC, CNRS-Nancy Université, BP 70239 Vandœuvre-lès Nancy, France
| | - Gérald Monard
- Equipe de Chimie et Biochimie Théoriques, UMR 7565 SRSMC, CNRS-Nancy Université, BP 70239 Vandœuvre-lès Nancy, France
| | - Marwa Hamdi Farag
- Departamento de Química Física, Universidad de Murcia, 30100 Murcia, Spain
| | - Adolfo Bastida
- Departamento de Química Física, Universidad de Murcia, 30100 Murcia, Spain
| | - Manuel F. Ruiz-López
- Equipe de Chimie et Biochimie Théoriques, UMR 7565 SRSMC, CNRS-Nancy Université, BP 70239 Vandœuvre-lès Nancy, France
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19
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Gaigeot MP, Besley NA, Hirst JD. Modeling the infrared and circular dichroism spectroscopy of a bridged cyclic diamide. J Phys Chem B 2011; 115:5526-35. [PMID: 21344909 DOI: 10.1021/jp111140f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Density functional theory based molecular dynamics simulations are used to study the structure, infrared (IR) spectroscopy, circular dichroism (CD) spectroscopy, and coupling between the amide I vibrations of a bridged cyclic diamide in the gas phase and in aqueous solution. IR spectra computed via the dipole moment time correlation function show a large red-shift of 30 cm(-1) in the amide I vibration in solution compared to the gas phase, and are in good agreement with experiment. Conformationally averaged CD spectra computed using the CIS(D) method are highly sensitive to the structures used, and structures sampled in the aqueous phase simulation are required to obtain qualitatively correct CD spectra. Analysis of the coupling between the amide I modes shows that in the aqueous phase there is an increased localization of the vibrations on the individual peptide groups and a reduction in the mode coupling parameter compared to the gas phase. Overall, the results illustrate the significance of incorporating molecular dynamics in the simulation of IR and CD spectra.
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Affiliation(s)
- Marie-Pierre Gaigeot
- Université d'Evry Val d'Essonne, LAMBE UMR8587 Laboratoire Analyse et Modélisation pour la Biologie et l'Environment, Blvd F. Mitterrand, Bât. Maupertuis, 91025 Evry, France
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20
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Salanne M, Simon C, Madden PA. Optical basicity scales in protic solvents: water, hydrogen fluoride, ammonia and their mixtures. Phys Chem Chem Phys 2011; 13:6305-8. [DOI: 10.1039/c0cp01639j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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