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Li H, Cao S, Zhang S, Chen J, Xu J, Knutson JR. Ultrafast Förster resonance energy transfer from tyrosine to tryptophan in monellin: potential intrinsic spectroscopic ruler. Phys Chem Chem Phys 2023; 25:7239-7250. [PMID: 36853740 DOI: 10.1039/d2cp05842a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Ultrafast Förster Resonance Energy Transfer (FRET) between tyrosine (Tyr) and tryptophan (Trp) residues in the protein monellin has been investigated using picosecond and femtosecond time-resolved fluorescence spectroscopy. Decay associated spectra (DAS) and time-resolved emission spectra (TRES) taken with the different excitation wavelengths of 275, 290 and 295 nm were constructed via global analysis. At two of those three excitation loci (275 and 290 nm), earmarks of energy transfer from Tyr to Trp in monellin are seen, and particularly when the excitation is 275 nm, the energy transfer between Tyr and Trp clearly changes the signature emission DAS shape to that indicating excited state reaction (especially on the red side of fluorescence emission, near 380 nm). Those FRET signatures may overlap with the conventional signatory DAS in heterogeneous systems. When overlap and addition occur between FRET type DAS and "full positive" QSSQ (quasi-static self-quenching), mixed DAS shapes will emerge that still show "positive blue side and negative red sides", just with zero crossing shifted. In addition, excitation decay associated spectra (EDAS) taken with the different emission wavelengths of 330, 350 and 370 nm were constructed. In the study of protein dynamics, ultrafast FRET between Tyr and Trp could provide a basis for an intrinsic (non-perturbing) "spectroscopic ruler", potentially a powerful tool to detect even slight changes in protein structures.
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Affiliation(s)
- Haoyang Li
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Simin Cao
- Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, Hangzhou 310024, China
| | - Sanjun Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Jianhua Xu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Jay R Knutson
- Laboratory of Advanced Microscopy & Biophotonics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
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Li H, Cao S, Chen J, Zhang S, Xu J, Knutson JR. Ultrafast fluorescence dynamics of NADH in aprotic solvents: Quasi-static self-quenching unmasked. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2022.114384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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3
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Li H, Jiang G, Jia M, Cao S, Zhang S, Chen J, Sun H, Xu J, Knutson JR. Ultrafast Förster resonance energy transfer between tyrosine and tryptophan: potential contributions to protein-water dynamics measurements. Phys Chem Chem Phys 2022; 24:18055-18066. [PMID: 35861343 DOI: 10.1039/d2cp02139k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Ultrafast Förster Resonance Energy Transfer (FRET) between Tyrosine (Tyr, Y) and Tryptophan (Trp, W) in the model peptides Trp-(Pro)n-Tyr (WPnY) has been investigated using a femtosecond up-conversion spectrophotofluorometer. The ultrafast energy transfer process (<100 ps) in short peptides (WY, WPY and WP2Y) has been resolved. In fact, this FRET rate is found to be mixed with the rates of solvent relaxation (SR), ultrafast population decay (QSSQ) and other lifetime components. To further dissect and analyze the FRET, a spectral working model is constructed, and the contribution of a FRET lifetime is separated by reconciling the shapes of decay associated spectra (DAS). Surprisingly, FRET efficiency did not decrease monotonically with the growth of the peptide chain (as expected) but increased first and then decreased. The highest FRET efficiency occurred in peptide WPY. The kinetic results have been accompanied with molecular dynamics simulations that reconcile and explain this strange phenomenon: due to the strong interaction between amino acids, the distance between the donor and receptor in peptide WPY is actually closest, resulting in the fastest FRET. In addition, the FRET lifetimes (τcal) were estimated within the molecular dynamics simulations, and they were consistent with the lifetimes (τexp) separated out by the experimental measurements and the DAS working model. This benchmark study has implications for both previous and future studies of protein ultrafast dynamics. The approach taken can be generalized for the study of proximate tyrosine and tryptophan in proteins and it suggests spectral strategies for extracting mixed rates in other complex FRET problems.
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Affiliation(s)
- Haoyang Li
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Guanyu Jiang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Menghui Jia
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Simin Cao
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Sanjun Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Haitao Sun
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Jianhua Xu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
| | - Jay R Knutson
- Laboratory of Advanced Microscopy & Biophotonics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
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4
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Energy-based fragmentation contribution approach for calculating the fluorescence spectrum of biomacromolecules. Chem Phys 2022. [DOI: 10.1016/j.chemphys.2021.111425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Oleinikov VA, Solovyeva DO, Zaitsev SY. Nanohybrid Structures Based on Plasmonic or Fluorescent Nanoparticles and Retinal-Containing Proteins. BIOCHEMISTRY (MOSCOW) 2020; 85:S196-S212. [PMID: 32087060 DOI: 10.1134/s0006297920140102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Rhodopsins are light-sensitive membrane proteins enabling transmembrane charge separation (proton pump) on absorption of a light quantum. Bacteriorhodopsin (BR) is a transmembrane protein from halophilic bacteria that belongs to the rhodopsin family. Potential applications of BR are considered so promising that the number of studies devoted to the use of BR itself, its mutant variants, as well as hybrid materials containing BR in various areas grows steadily. Formation of hybrid structures combining BR with nanoparticles is an essential step in promotion of BR-based devices. However, rapid progress, continuous emergence of new data, as well as challenges of analyzing the entire data require regular reviews of the achievements in this area. This review is devoted to the issues of formation of materials based on hybrids of BR with fluorescent semiconductor nanocrystals (quantum dots) and with noble metal (silver, gold) plasmonic nanoparticles. Recent data on formation of thin (mono-) and thick (multi-) layers from materials containing BR and BR/nanoparticle hybrids are presented.
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Affiliation(s)
- V A Oleinikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia. .,Institute of Engineering Physics for Biomedicine, National Research Nuclear University MEPhI, Moscow, 115409, Russia
| | - D O Solovyeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia.,Institute of Engineering Physics for Biomedicine, National Research Nuclear University MEPhI, Moscow, 115409, Russia
| | - S Yu Zaitsev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia.,L. K. Ernst Federal Science Center for Animal Husbandry, Dubrovitsy, Moscow Region, 142132, Russia
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6
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Purnell GE, McNally MT, Callis PR, Walker RA. Buried Liquid Interfaces as a Form of Chemistry in Confinement: The Case of 4-Dimethylaminobenzonitrile at the Silica–Aqueous Interface. J Am Chem Soc 2020; 142:2375-2385. [DOI: 10.1021/jacs.9b11662] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Grace E. Purnell
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Marshall T. McNally
- Montana Materials Science Program, Montana State University, Bozeman, Montana 59717, United States
| | - Patrik R. Callis
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Robert A. Walker
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
- Montana Materials Science Program, Montana State University, Bozeman, Montana 59717, United States
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7
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Fukuda A, Oroguchi T, Nakasako M. Dipole-dipole interactions between tryptophan side chains and hydration water molecules dominate the observed dynamic stokes shift of lysozyme. Biochim Biophys Acta Gen Subj 2019; 1864:129406. [PMID: 31377191 DOI: 10.1016/j.bbagen.2019.07.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 07/24/2019] [Accepted: 07/29/2019] [Indexed: 10/26/2022]
Abstract
The fluorescence intensity of tryptophan residues in hen egg-white lysozyme was measured up to 500 ps after the excitation by irradiation pulses at 290 nm. From the time-dependent variation of fluorescence intensity in a wavelength range of 320-370 nm, the energy relaxation in the dynamic Stokes shift was reconstructed as the temporal variation in wavenumber of the estimated fluorescence maximum. The relaxation was approximated by two exponential curves with decay constants of 1.2 and 26.7 ps. To interpret the relaxation, a molecular dynamics simulation of 75 ns was conducted for lysozyme immersed in a water box. From the simulation, the energy relaxation in the electrostatic interactions of each tryptophan residue was evaluated by using a scheme derived from the linear response theory. Dipole-dipole interactions between each of the Trp62 and Trp123 residues and hydration water molecules displayed an energy relaxation similar to that experimentally observed regarding time constants and magnitudes. The side chains of these residues were partly or fully exposed to the solvent. In addition, by inspecting the variation in dipole moments of the hydration water molecules around lysozyme, it was suggested that the observed relaxation could be attributed to the orientational relaxation of hydration water molecules participating in the hydrogen-bond network formed around each of the two tryptophan residues.
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Affiliation(s)
- Asahi Fukuda
- Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokihama 223-8522, Japan
| | - Tomotaka Oroguchi
- Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokihama 223-8522, Japan
| | - Masayoshi Nakasako
- Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokihama 223-8522, Japan.
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Cao S, Zhou Z, Li H, Jia M, Liu Y, Wang M, Zhang M, Zhang S, Chen J, Xu J, Knutson JR. A fraction of NADH in solution is "dark": Implications for metabolic sensing via fluorescence lifetime. Chem Phys Lett 2019; 726:18-21. [PMID: 32921799 PMCID: PMC7486008 DOI: 10.1016/j.cplett.2019.04.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The metabolic cofactor and energy carrier NADH (nicotinamide adenine dinucleotide, reduced) has fluorescence yield and lifetime that depends strongly on conformation, a fact that has enabled metabolic monitoring of cells via FLIM (Fluorescence Lifetime Microscopy). Using femtosecond fluorescence upconversion, we show that this molecule in solution participates in ultrafast self-quenching along with both bulk solvent relaxation and spectral relaxation on 1.4 and 26 ps timescales. This, in effect, means up to a third of NADH is effectively "dark" for FLIM in the 400-500 nm observation window commonly employed. Methods to compensate for, avoid or measure dark species corrections are outlined.
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Affiliation(s)
- Simin Cao
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Zhongneng Zhou
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Haoyang Li
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Menghui Jia
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Yangyi Liu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Mengyu Wang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Mengjie Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Sanjun Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Jianhua Xu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Jay R. Knutson
- Laboratory for Advanced Microscopy and Biophotonics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, United States
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Cote JM, Ramirez-Mondragon CA, Siegel ZS, Czyzyk DJ, Gao J, Sham YY, Mukerji I, Taylor EA. The Stories Tryptophans Tell: Exploring Protein Dynamics of Heptosyltransferase I from Escherichia coli. Biochemistry 2017; 56:886-895. [PMID: 28098447 DOI: 10.1021/acs.biochem.6b00850] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Heptosyltransferase I (HepI) catalyzes the addition of l-glycero-β-d-manno-heptose to Kdo2-Lipid A, as part of the biosynthesis of the core region of lipopolysaccharide (LPS). Gram-negative bacteria with gene knockouts of HepI have reduced virulence and enhanced susceptibility to hydrophobic antibiotics, making the design of inhibitors of HepI of interest. Because HepI protein dynamics are partially rate-limiting, disruption of protein dynamics might provide a new strategy for inhibiting HepI. Discerning the global mechanism of HepI is anticipated to aid development of inhibitors of LPS biosynthesis. Herein, dynamic protein rearrangements involved in the HepI catalytic cycle were probed by combining mutagenesis with intrinsic tryptophan fluorescence and circular dichroism analyses. Using wild-type and mutant forms of HepI, multiple dynamic regions were identified via changes in Trp fluorescence. Interestingly, Trp residues (Trp199 and Trp217) in the C-terminal domain (which binds ADP-heptose) are in a more hydrophobic environment upon binding of ODLA to the N-terminal domain. These residues are adjacent to the ADP-heptose binding site (with Trp217 in van der Waals contact with the adenine ring of ADP-heptose), suggesting that the two binding sites interact to report on the occupancy state of the enzyme. ODLA binding was also accompanied by a significant stabilization of HepI (heating to 95 °C fails to denature the protein when it is in the presence of ODLA). These results suggest that conformational rearrangements, from an induced fit model of substrate binding to HepI, are important for catalysis, and the disruption of these conformational dynamics may serve as a novel mechanism for inhibiting this and other glycosyltransferase enzymes.
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Affiliation(s)
- Joy M Cote
- Department of Chemistry, Wesleyan University , Middletown, Connecticut 06459, United States
| | | | - Zarek S Siegel
- Department of Chemistry, Wesleyan University , Middletown, Connecticut 06459, United States
| | - Daniel J Czyzyk
- Department of Chemistry, Wesleyan University , Middletown, Connecticut 06459, United States
| | | | | | - Ishita Mukerji
- Molecular Biophysics Program, Department of Molecular Biology and Biochemistry, Wesleyan University , Middletown, Connecticut 06459, United States
| | - Erika A Taylor
- Department of Chemistry, Wesleyan University , Middletown, Connecticut 06459, United States
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Qin Y, Jia M, Yang J, Wang D, Wang L, Xu J, Zhong D. Molecular Origin of Ultrafast Water-Protein Coupled Interactions. J Phys Chem Lett 2016; 7:4171-4177. [PMID: 27700094 DOI: 10.1021/acs.jpclett.6b01954] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The fluctuations of hydration water and the protein are coupled together at the protein surface and often such water-protein dynamic interactions are controlled presumably by hydration water motions. However, direct evidence is scarce and it requires measuring the dynamics of hydration water and protein side chain simultaneously. Here, we use a unique protein with a single tryptophan to directly probe interfacial water and related side chain relaxations with temperature dependence. With systematic mutations to change local chemical identity and structural flexibility, we found that the side chain relaxations are always slower than hydration water motions and the two dynamic processes are linearly correlated with the same energy barriers, indicating the same origin of both relaxations. The charge mutations change the rates of hydration water relaxations but not the relaxation barriers. These results convincingly show that the water-protein relaxations are strongly coupled and the hydration water molecules govern such fluctuations on the picosecond time scales.
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Affiliation(s)
- Yangzhong Qin
- State Key Laboratory of Precision Spectroscopy, East China Normal University , Shanghai 200062, China
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
| | - Menghui Jia
- State Key Laboratory of Precision Spectroscopy, East China Normal University , Shanghai 200062, China
| | - Jin Yang
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
| | - Dihao Wang
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
| | - Lijuan Wang
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
| | - Jianhua Xu
- State Key Laboratory of Precision Spectroscopy, East China Normal University , Shanghai 200062, China
| | - Dongping Zhong
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
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Hydration of proteins and nucleic acids: Advances in experiment and theory. A review. Biochim Biophys Acta Gen Subj 2016; 1860:1821-35. [PMID: 27241846 DOI: 10.1016/j.bbagen.2016.05.036] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 05/20/2016] [Accepted: 05/26/2016] [Indexed: 11/21/2022]
Abstract
BACKGROUND Most biological processes involve water, and the interactions of biomolecules with water affect their structure, function and dynamics. SCOPE OF REVIEW This review summarizes the current knowledge of protein and nucleic acid interactions with water, with a special focus on the biomolecular hydration layer. Recent developments in both experimental and computational methods that can be applied to the study of hydration structure and dynamics are reviewed, including software tools for the prediction and characterization of hydration layer properties. MAJOR CONCLUSIONS In the last decade, important advances have been made in our understanding of the factors that determine how biomolecules and their aqueous environment influence each other. Both experimental and computational methods contributed to the gradually emerging consensus picture of biomolecular hydration. GENERAL SIGNIFICANCE An improved knowledge of the structural and thermodynamic properties of the hydration layer will enable a detailed understanding of the various biological processes in which it is involved, with implications for a wide range of applications, including protein-structure prediction and structure-based drug design.
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Xu J, Chen B, Callis P, Muiño PL, Rozeboom H, Broos J, Toptygin D, Brand L, Knutson JR. Picosecond fluorescence dynamics of tryptophan and 5-fluorotryptophan in monellin: slow water-protein relaxation unmasked. J Phys Chem B 2015; 119:4230-9. [PMID: 25710196 PMCID: PMC7477844 DOI: 10.1021/acs.jpcb.5b01651] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Time dependent fluorescence Stokes (emission wavelength) shifts (TDFSS) from tryptophan (Trp) following sub-picosecond excitation are increasingly used to investigate protein dynamics, most recently enabling active research interest into water dynamics near the surface of proteins. Unlike many fluorescence probes, both the efficiency and the wavelength of Trp fluorescence in proteins are highly sensitive to microenvironment, and Stokes shifts can be dominated by the well-known heterogeneous nature of protein structure, leading to what we call pseudo-TDFSS: shifts that arise from differential decay rates of subpopulations. Here we emphasize a novel, general method that obviates pseudo-TDFSS by replacing Trp by 5-fluorotryptophan (5Ftrp), a fluorescent analogue with higher ionization potential and greatly suppressed electron-transfer quenching. 5FTrp slows and suppresses pseudo-TDFSS, thereby providing a clearer view of genuine relaxation caused by solvent and protein response. This procedure is applied to the sweet-tasting protein monellin which has uniquely been the subject of ultrafast studies in two different laboratories (Peon, J.; et al. Proc. Natl. Acad. Sci. U.S.A. 2002, 99, 10964; Xu, J.; et al. J. Am. Chem. Soc. 2006, 128, 1214) that led to disparate interpretations of a 20 ps transient. They differed because of the pseudo-TDFSS present. The current study exploiting special properties of 5FTrp strongly supports the conclusion that both lifetime heterogeneity-based TDFSS and environment relaxation-based TDFSS are present in monellin and 5FTrp-monellin. The original experiments on monellin were most likely dominated by pseudo-TDFSS, whereas, in the present investigation of 5FTrp-monellin, the TDFSS is dominated by relaxation and any residual pseudo-TDFSS is overwhelmed and/or slowed to irrelevance.
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Affiliation(s)
- Jianhua Xu
- Optical Spectroscopy Section, Laboratory of Molecular Biophysics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Binbin Chen
- Optical Spectroscopy Section, Laboratory of Molecular Biophysics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Patrik Callis
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Pedro L. Muiño
- Department of Chemistry, Saint Francis University, Loretto, Pennsylvania 15940, United States
| | - Henriëtte Rozeboom
- Department of Biophysical Chemistry, Groningen Biomolecular Science and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Jaap Broos
- Department of Biophysical Chemistry, Groningen Biomolecular Science and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Dmitri Toptygin
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Ludwig Brand
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Jay R. Knutson
- Optical Spectroscopy Section, Laboratory of Molecular Biophysics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
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13
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Callis PR. Simulating electrostatic effects on electronic transitions in proteins. MOLECULAR SIMULATION 2014. [DOI: 10.1080/08927022.2014.923571] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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