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Pei R, Zhang J, Tan J, Luo Y, Ye S. Fermi Resonance of the N-D Stretching Mode Probing the Local Hydrogen-Bonding Environment in Proteins. J Phys Chem B 2024; 128:5658-5666. [PMID: 38836292 DOI: 10.1021/acs.jpcb.4c00390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
Local H-bonding interactions are crucial for proteins to undergo various structural transitions and form different secondary structures. However, identifying slight distinctions in the local H-bonding of proteins is rather challenging. Here, we demonstrate that the Fermi resonance of the N-D stretching mode can provide an effective probe for the localized H-bonding environment of proteins both at the surface/interface and in the bulk. Using sum frequency generation vibrational spectroscopy and infrared spectroscopy, we established a correlation between the Fermi resonance of the N-D mode and protein secondary structures. The H-bond of N-D···C═O splits the N-D modes into two peaks (∼2410 and ∼2470 cm-1). The relative strength ratio (R) between the ∼2410 cm-1 peak and the ∼2470 cm-1 peak is very sensitive to H-bond strength and protein secondary structure. R is less than 1 for α-helical peptides, while R is greater than 1 for β-sheet peptides. For R < 2.5, both α-helical/loop structures and β-sheet structures exhibit almost identical Fermi coupling strengths (W = 28 cm-1). For R > 2.5, W decreases from 28 to 14 cm-1 and depends on the aggregation degree of the β-sheet oligomers or fibrils. The initial local H-bonding status impacts the misfolding dynamics of proteins at the lipid bilayer interface.
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Affiliation(s)
- Ruoqi Pei
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Jiahui Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Junjun Tan
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Yi Luo
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Shuji Ye
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
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2
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Shirley JC, Baiz CR. MANUSCRIPT Local Crowd, Local Probe: Strengths and Drawbacks of Azidohomoalanine as a Site-Specific Crowding Probe. J Phys Chem B 2024; 128:5310-5319. [PMID: 38806061 DOI: 10.1021/acs.jpcb.4c00712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
Every residue on a protein can be characterized by its interaction with water, in lack or in excess, as water is the matrix of biological systems. Infrared spectroscopy and the implementation of local azidohomoalanine (AHA) probes allow us to move beyond an ensemble or surface-driven conceptualization of water behavior and toward a granular, site-specific picture. In this paper, we examined the role of crowding in modulating both global and local behavior on the β-hairpin, TrpZip2 using a combination of Fourier-transform infrared spectroscopy (FTIR) spectroscopy, two-dimensional infrared (2D IR) spectroscopy, and molecular dynamics simulations. We found that, at the amino acid level, crowding drove dehydration of both sheet and turn peptide sites as well as free AHA. However, the subpicosecond dynamics showed highly individualized responses based on the local environment. Interestingly, while steady-state FTIR measurements revealed similar responses at the amino-acid level to hard versus soft crowding (dehydration), we found that PEG and glucose had opposite stabilizing and destabilizing effects on the protein secondary structure, emphasizing an important distinction in understanding the impact of crowding on protein structure as well as the role of crowding across length scales.
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Affiliation(s)
- Joseph C Shirley
- Department of Chemistry, University of Texas, Austin 78712, Texas, United States
| | - Carlos R Baiz
- Department of Chemistry, University of Texas, Austin 78712, Texas, United States
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3
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Sakpal S, Chakrabarty S, Reddy KD, Deshmukh SH, Biswas R, Bagchi S, Ghosh A. Perturbation of Fermi Resonance on Hydrogen-Bonded > C═O: 2D IR Studies of Small Ester Probes. J Phys Chem B 2024. [PMID: 38686937 DOI: 10.1021/acs.jpcb.3c06698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
We utilized linear and 2D infrared spectroscopy to analyze the carbonyl stretching modes of small esters in different solvents. Particularly noteworthy were the distinct carbonyl spectral line shapes in aqueous solutions, prompting our investigation of the underlying factors responsible for these differences. Through our experimental and theoretical calculations, we identified the presence of the hydrogen-bond-induced Fermi resonance as the primary contributor to the varied line shapes of small esters in aqueous solutions. Furthermore, our findings revealed that the skeletal deformation mode plays a crucial role in the Fermi resonance for all small esters. Specifically, the first overtone band of the skeletal deformation mode intensifies when hydrogen bonds form with the carbonyl group of esters, whereas such coupling is rare in aprotic organic solvents. These spectral insights carry significant implications for the utilization of esters as infrared probes in both biological and chemical systems.
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Affiliation(s)
- Sushil Sakpal
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Suranjana Chakrabarty
- Department of Condensed Matter Physics and Materials Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata 700106, India
| | - Kambham Devendra Reddy
- Department of Chemistry, Indian Institute of Technology Tirupati, Tirupati, Andhra Pradesh, India 517619
| | - Samadhan H Deshmukh
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Rajib Biswas
- Department of Chemistry, Indian Institute of Technology Tirupati, Tirupati, Andhra Pradesh, India 517619
| | - Sayan Bagchi
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Anup Ghosh
- Department of Condensed Matter Physics and Materials Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata 700106, India
- Department of Chemical Science, Bose Institute, Kolkata 700091, India
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4
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Taniguchi T, Agbo DO. Vibrational circular dichroism spectroscopy in the C-D, XY, and XYZ stretching region. Phys Chem Chem Phys 2023; 25:28567-28575. [PMID: 37861094 DOI: 10.1039/d3cp04287a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
Vibrational circular dichroism (VCD) spectroscopy is a powerful technique for structural analysis of chiral molecules, but information available from VCD spectra of large molecular systems can be limited by severe overlap of vibrational bands. While common chiral molecules do not absorb in the 1900-2400 cm-1 region, observation of VCD signals in this spectrally-isolated region is possible for molecules containing C-D, XY, and XYZ chromophores. Thus, a strategic introduction of these chromophores to a target molecule may produce VCD signals informative for molecular structures. VCD spectroscopy in the 1900-2400 cm-1 region is a rather unexplored research field and its basic properties remain to be investigated. This perspective article discusses insight obtained so far on the usefulness and physicochemical aspects of VCD spectroscopy in this region with briefly summarizing previous experimental VCD studies including classic examples as well as our recent results. We show that anharmonic effects such as overtones and combination bands often complicate VCD patterns. On the other hand, some molecules exhibit characteristic VCD signals that can be well interpreted by harmonic DFT spectral calculations for structural analysis. This article also discusses several examples of the use of this region for studying solute-solvent interactions and for VCD signal augmentation.
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Affiliation(s)
- Tohru Taniguchi
- Frontier Research Center for Advanced Material and Life Science, Faculty of Advanced Life Science, Hokkaido University, North 21 West 11, Sapporo 001-0021, Japan.
| | - Davidson Obinna Agbo
- Graduate School of Life Science, Hokkaido University, North 21 West 11, Sapporo 001-0021, Japan
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5
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Löffler JG, Deniz E, Feid C, Franz VG, Bredenbeck J. Versatile Vibrational Energy Sensors for Proteins. Angew Chem Int Ed Engl 2022; 61:e202200648. [PMID: 35226765 PMCID: PMC9401566 DOI: 10.1002/anie.202200648] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Indexed: 11/10/2022]
Abstract
Vibrational energy transfer (VET) is emerging as key mechanism for protein functions, possibly playing an important role for energy dissipation, allosteric regulation, and enzyme catalysis. A deep understanding of VET is required to elucidate its role in such processes. Ultrafast VIS-pump/IR-probe spectroscopy can detect pathways of VET in proteins. However, the requirement of having a VET donor and a VET sensor installed simultaneously limits the possible target proteins and sites; to increase their number we compare six IR labels regarding their utility as VET sensors. We compare these labels in terms of their FTIR, and VET signature in VET donor-sensor dipeptides in different solvents. Furthermore, we incorporated four of these labels in PDZ3 to assess their capabilities in more complex systems. Our results show that different IR labels can be used interchangeably, allowing for free choice of the right label depending on the system under investigation and the methods available.
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Affiliation(s)
- Jan G. Löffler
- Institute of BiophysicsGoethe University FrankfurtMax-von-Laue-Straße 160438Frankfurt (Main)Germany
| | - Erhan Deniz
- Institute of BiophysicsGoethe University FrankfurtMax-von-Laue-Straße 160438Frankfurt (Main)Germany
| | - Carolin Feid
- Institute of BiophysicsGoethe University FrankfurtMax-von-Laue-Straße 160438Frankfurt (Main)Germany
| | - Valentin G. Franz
- Institute of BiophysicsGoethe University FrankfurtMax-von-Laue-Straße 160438Frankfurt (Main)Germany
| | - Jens Bredenbeck
- Institute of BiophysicsGoethe University FrankfurtMax-von-Laue-Straße 160438Frankfurt (Main)Germany
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6
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Löffler JG, Deniz E, Feid C, Franz VG, Bredenbeck J. Versatile Vibrational Energy Sensors for Proteins. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jan G. Löffler
- Institute of Biophysics Goethe University Frankfurt Max-von-Laue-Straße 1 60438 Frankfurt (Main) Germany
| | - Erhan Deniz
- Institute of Biophysics Goethe University Frankfurt Max-von-Laue-Straße 1 60438 Frankfurt (Main) Germany
| | - Carolin Feid
- Institute of Biophysics Goethe University Frankfurt Max-von-Laue-Straße 1 60438 Frankfurt (Main) Germany
| | - Valentin G. Franz
- Institute of Biophysics Goethe University Frankfurt Max-von-Laue-Straße 1 60438 Frankfurt (Main) Germany
| | - Jens Bredenbeck
- Institute of Biophysics Goethe University Frankfurt Max-von-Laue-Straße 1 60438 Frankfurt (Main) Germany
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7
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Ruppert M, Creon A, Tidow H, Huse N. Population Dynamics of Stretching Excitations of p-Azido-phenylalanine Incorporated in Calmodulin-Peptide Complexes. J Phys Chem B 2022; 126:368-375. [PMID: 34990136 DOI: 10.1021/acs.jpcb.1c06775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We genetically incorporated the unnatural amino acid p-azido-phenylalanine (AzF) into the ubiquitous Ca2+ sensor protein calmodulin (CaM) in complex with different peptides to explore the response of the azido stretching line shape to varying binding motifs with femtosecond infrared spectroscopy. The dynamic response of the azido stretching mode varies in different CaM-peptide complexes. We model these dynamics as coherent excitations of Fermi resonances and extract a lifetime of the azido stretching vibration of about 1 ps. The resulting model parameters are commensurate with the linear infrared absorption lineshapes which suggests that the conformation-sensitive vibrational lineshape could be composed of Fermi resonances that differ between the protein-peptide complexes.
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Affiliation(s)
- Matthias Ruppert
- Hamburg Advanced Research Centre for Bioorganic Chemistry, Institute for Nanostructure and Solid-State Physics, Department of Physics, and Center for Free-Electron Laser Science, University of Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
| | - Anne Creon
- Hamburg Advanced Research Centre for Bioorganic Chemistry, Institute for Nanostructure and Solid-State Physics, Department of Physics, and Center for Free-Electron Laser Science, University of Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany.,Hamburg Advanced Research Centre for Bioorganic Chemistry, Institute for Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, D-20146 Hamburg, Germany
| | - Henning Tidow
- Hamburg Advanced Research Centre for Bioorganic Chemistry, Institute for Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, D-20146 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, University of Hamburg, Luruper Chaussee, 149, D-22761 Hamburg, Germany
| | - Nils Huse
- Hamburg Advanced Research Centre for Bioorganic Chemistry, Institute for Nanostructure and Solid-State Physics, Department of Physics, and Center for Free-Electron Laser Science, University of Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany.,The Hamburg Centre for Ultrafast Imaging, University of Hamburg, Luruper Chaussee, 149, D-22761 Hamburg, Germany
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8
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Kwon HJ, Gwak S, Park JY, Cho M, Han H. TfNN 15N: A γ- 15N-Labeled Diazo-Transfer Reagent for the Synthesis of β- 15N-Labeled Azides. ACS OMEGA 2022; 7:293-298. [PMID: 35036700 PMCID: PMC8757338 DOI: 10.1021/acsomega.1c04679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 11/30/2021] [Indexed: 06/14/2023]
Abstract
Azides are infrared (IR) probes that are important for structure and dynamics studies of proteins. However, they often display complex IR spectra owing to Fermi resonances and multiple conformers. Isotopic substitution of azides weakens the Fermi resonance, allowing more accurate IR spectral analysis. Site-specifically 15N-labeled aromatic azides, but not aliphatic azides, are synthesized through nitrosation. Both 15N-labeled aromatic and aliphatic azides are synthesized through nucleophilic substitution or diazo-transfer reaction but as an isotopomeric mixture. We present the synthesis of TfNN15N, a γ-15N-labeled diazo-transfer reagent, and its use to prepare β-15N-labeled aliphatic as well as aromatic azides.
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Affiliation(s)
- Hyeok-Jun Kwon
- Department
of Chemistry, Korea University, Seoul 02841, Korea
| | - Sungduk Gwak
- Department
of Chemistry, Korea University, Seoul 02841, Korea
| | - Jun Young Park
- Department
of Chemistry, Korea University, Seoul 02841, Korea
- Center
for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul 02841, Korea
| | - Minhaeng Cho
- Department
of Chemistry, Korea University, Seoul 02841, Korea
- Center
for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul 02841, Korea
| | - Hogyu Han
- Department
of Chemistry, Korea University, Seoul 02841, Korea
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9
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Taniguchi T, Zubir MZM, Harada N, Monde K. Exploration of chromophores for a VCD couplet in a spectrally transparent infrared region for biomolecules. Phys Chem Chem Phys 2021; 23:27525-27532. [PMID: 34874381 DOI: 10.1039/d1cp04074j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Interactions of two chromophores such as carbonyl groups yield a strong VCD couplet that reflects the molecular structures. The use of VCD couplets for biomacromolecular structural studies has been hampered by severe signal overlap caused by numerous functional groups that originally exist in biomacromolecules. Nitrile, isonitrile, alkyne, and azido groups show characteristic IR absorption in the 2300-2000 cm-1 region, where biomolecules do not strongly absorb. We herein examined the usefulness of these functional groups as chromophores to observe a strong VCD couplet that can be readily interpreted using theoretical calculations. Studies on a chiral binaphthyl scaffold possessing two identical chromophores showed that nitrile and isonitrile groups generate moderately-strong but complex VCD signals due to anharmonic contributions. The nature of their anharmonic VCD patterns is discussed by comparison with the VCD spectrum of a mono-chromophoric molecule and by anharmonic DFT calculations. On the other hand, through studies on diazido binaphthyl and diazido monosaccharide, we demonstrated that the azido group is more promising for structural analysis of larger molecules due to its simple, strong VCD couplet whose spectral patterns are readily predicted by harmonic DFT calculations.
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Affiliation(s)
- Tohru Taniguchi
- Frontier Research Center for Advanced Material and Life Science, Faculty of Advanced Life Science, Hokkaido University, Kita 21 Nishi 11, Sapporo 001-0021, Japan.
| | | | - Nobuyuki Harada
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
| | - Kenji Monde
- Frontier Research Center for Advanced Material and Life Science, Faculty of Advanced Life Science, Hokkaido University, Kita 21 Nishi 11, Sapporo 001-0021, Japan.
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10
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Thielges MC. Transparent window 2D IR spectroscopy of proteins. J Chem Phys 2021; 155:040903. [PMID: 34340394 PMCID: PMC8302233 DOI: 10.1063/5.0052628] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/21/2021] [Indexed: 02/01/2023] Open
Abstract
Proteins are complex, heterogeneous macromolecules that exist as ensembles of interconverting states on a complex energy landscape. A complete, molecular-level understanding of their function requires experimental tools to characterize them with high spatial and temporal precision. Infrared (IR) spectroscopy has an inherently fast time scale that can capture all states and their dynamics with, in principle, bond-specific spatial resolution. Two-dimensional (2D) IR methods that provide richer information are becoming more routine but remain challenging to apply to proteins. Spectral congestion typically prevents selective investigation of native vibrations; however, the problem can be overcome by site-specific introduction of amino acid side chains that have vibrational groups with frequencies in the "transparent window" of protein spectra. This Perspective provides an overview of the history and recent progress in the development of transparent window 2D IR of proteins.
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Affiliation(s)
- Megan C. Thielges
- Department of Chemistry, Indiana University, Bloomington,
Indiana 47405, USA
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11
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Tumbic GW, Hossan MY, Thielges MC. Protein Dynamics by Two-Dimensional Infrared Spectroscopy. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2021; 14:299-321. [PMID: 34314221 PMCID: PMC8713465 DOI: 10.1146/annurev-anchem-091520-091009] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Proteins function as ensembles of interconverting structures. The motions span from picosecond bond rotations to millisecond and longer subunit displacements. Characterization of functional dynamics on all spatial and temporal scales remains challenging experimentally. Two-dimensional infrared spectroscopy (2D IR) is maturing as a powerful approach for investigating proteins and their dynamics. We outline the advantages of IR spectroscopy, describe 2D IR and the information it provides, and introduce vibrational groups for protein analysis. We highlight example studies that illustrate the power and versatility of 2D IR for characterizing protein dynamics and conclude with a brief discussion of the outlook for biomolecular 2D IR.
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Affiliation(s)
- Goran W Tumbic
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, USA;
| | - Md Yeathad Hossan
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, USA;
| | - Megan C Thielges
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, USA;
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12
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Abstract
The spectroscopic response of and structural dynamics around all azido-modified alanine residues (AlaN3) in lysozyme are characterized. It is found that AlaN3 is a positionally sensitive probe for the local dynamics, covering a frequency range of ∼15 cm-1 for the center frequency of the line shape. This is consistent with findings from selective replacements of amino acids in PDZ2, which reported a frequency span of ∼10 cm-1 for replacements of Val, Ala, or Glu by azidohomoalanine. For the frequency fluctuation correlation functions, the long-time decay constants τ2 range from ∼1 to ∼10 ps, which compares with experimentally measured correlation times of 3 ps. Attaching azide to alanine residues can yield dynamics that decays to zero on the few ps time scale (i.e., static component Δ0 ∼ 0 ps-1) or to a remaining, static contribution of ∼0.5 ps-1 (corresponding to 2.5 cm-1), depending on the local environment on the 10 ps time scale. The magnitude of the static component correlates qualitatively with the degree of hydration of the spectroscopic probe. Although attaching azide to alanine residues is found to be structurally minimally invasive with respect to the overall protein structure, analysis of the local hydrophobicity indicates that the hydration around the modification site differs for modified and unmodified alanine residues, respectively.
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Affiliation(s)
- Seyedeh Maryam Salehi
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
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