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Gu J, Wang X, Zhao W, Zhuang R, Zhang C, Zhang X, Cai Y, Yuan W, Luan B, Dong B, Liu H. Synthesis of Half-Titanocene Complexes Containing π,π-Stacked Aryloxide Ligands, and Their Use as Catalysts for Ethylene (Co)polymerizations. Polymers (Basel) 2022; 14:polym14071427. [PMID: 35406299 PMCID: PMC9002825 DOI: 10.3390/polym14071427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/22/2022] [Accepted: 03/28/2022] [Indexed: 01/27/2023] Open
Abstract
A family of half-titanocene complexes bearing π,π-stacked aryloxide ligands and their catalytic performances towards ethylene homo-/co- polymerizations were disclosed herein. All the complexes were well characterized, and the intermolecular π,π-stacking interactions could be clearly identified from single crystal X-ray analysis, in which a stronger interaction could be reflected for aryloxides bearing bigger π-systems, e.g., pyrenoxide. Due to the formation of such interactions, these complexes were able to highly catalyze the ethylene homopolymerizations and copolymerization with 1-hexene comonomer, even without any additiveson the aryloxide group, which showed striking contrast to other half-titanocene analogues, implying the positive influence of π,π-stacking interaction in enhancing the catalytic performances of the corresponding catalysts. Moreover, it was found that addition of external pyrene molecules was capable of boosting the catalytic efficiency significantly, due to the formation of a stronger π,π-stacking interaction between the complexes and pyrene molecules.
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Affiliation(s)
- Jin Gu
- Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization, Chambroad Chemical Industry Research Institute Co., Ltd., Qingdao 266042, China; (J.G.); (R.Z.); (Y.C.); (W.Y.); (B.L.)
| | - Xiaohua Wang
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (C.Z.); (X.Z.)
| | - Wenpeng Zhao
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (C.Z.); (X.Z.)
| | - Rui Zhuang
- Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization, Chambroad Chemical Industry Research Institute Co., Ltd., Qingdao 266042, China; (J.G.); (R.Z.); (Y.C.); (W.Y.); (B.L.)
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
| | - Chunyu Zhang
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (C.Z.); (X.Z.)
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
| | - Xuequan Zhang
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (C.Z.); (X.Z.)
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
| | - Yinghui Cai
- Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization, Chambroad Chemical Industry Research Institute Co., Ltd., Qingdao 266042, China; (J.G.); (R.Z.); (Y.C.); (W.Y.); (B.L.)
| | - Wenbo Yuan
- Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization, Chambroad Chemical Industry Research Institute Co., Ltd., Qingdao 266042, China; (J.G.); (R.Z.); (Y.C.); (W.Y.); (B.L.)
| | - Bo Luan
- Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization, Chambroad Chemical Industry Research Institute Co., Ltd., Qingdao 266042, China; (J.G.); (R.Z.); (Y.C.); (W.Y.); (B.L.)
| | - Bo Dong
- Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization, Chambroad Chemical Industry Research Institute Co., Ltd., Qingdao 266042, China; (J.G.); (R.Z.); (Y.C.); (W.Y.); (B.L.)
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- Correspondence: (B.D.); (H.L.)
| | - Heng Liu
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (C.Z.); (X.Z.)
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
- Correspondence: (B.D.); (H.L.)
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Kajita K, Nakano H, Sato H. A theoretical study on the optical absorption of green fluorescent protein chromophore in solutions. MOLECULAR SIMULATION 2017. [DOI: 10.1080/08927022.2017.1315769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Ken Kajita
- Department of Molecular Engineering, Kyoto University, Kyoto, Japan
| | - Hiroshi Nakano
- Department of Molecular Engineering, Kyoto University, Kyoto, Japan
- Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto, Japan
| | - Hirofumi Sato
- Department of Molecular Engineering, Kyoto University, Kyoto, Japan
- Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto, Japan
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Zutterman F, Liégeois V, Champagne B. Simulation of the UV/Visible Absorption Spectra of Fluorescent Protein Chromophore Models. CHEMPHOTOCHEM 2017. [DOI: 10.1002/cptc.201700002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Freddy Zutterman
- Laboratoire de Chimie Théorique, Unité de Chimie-Physique Théorique et Structurale; Université de Namur; rue de Bruxelles, 61 B-5000 Namur Belgium
| | - Vincent Liégeois
- Laboratoire de Chimie Théorique, Unité de Chimie-Physique Théorique et Structurale; Université de Namur; rue de Bruxelles, 61 B-5000 Namur Belgium
| | - Benoît Champagne
- Laboratoire de Chimie Théorique, Unité de Chimie-Physique Théorique et Structurale; Université de Namur; rue de Bruxelles, 61 B-5000 Namur Belgium
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Long- and Short-Range Electrostatic Fields in GFP Mutants: Implications for Spectral Tuning. Sci Rep 2015; 5:13223. [PMID: 26286372 PMCID: PMC4541067 DOI: 10.1038/srep13223] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 07/20/2015] [Indexed: 12/27/2022] Open
Abstract
The majority of protein functions are governed by their internal local electrostatics. Quantitative information about these interactions can shed light on how proteins work and allow for improving/altering their performance. Green fluorescent protein (GFP) and its mutation variants provide unique optical windows for interrogation of internal electric fields, thanks to the intrinsic fluorophore group formed inside them. Here we use an all-optical method, based on the independent measurements of transition frequency and one- and two-photon absorption cross sections in a number of GFP mutants to evaluate these internal electric fields. Two physical models based on the quadratic Stark effect, either with or without taking into account structural (bond-length) changes of the chromophore in varying field, allow us to separately evaluate the long-range and the total effective (short- and long-range) fields. Both types of the field quantitatively agree with the results of independent molecular dynamic simulations, justifying our method of measurement.
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Huang TH, Zhang MH. Novel copper(I) complexes with extended π⋯π interactions: Synthesis, structure, characterization and spectroscopic properties. Inorganica Chim Acta 2014. [DOI: 10.1016/j.ica.2014.03.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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List NH, Olsen JMH, Jensen HJA, Steindal AH, Kongsted J. Molecular-Level Insight into the Spectral Tuning Mechanism of the DsRed Chromophore. J Phys Chem Lett 2012; 3:3513-3521. [PMID: 26290981 DOI: 10.1021/jz3014858] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a detailed study of the protein environmental effects on the one- and two-photon absorption (1PA and 2PA, respectively) properties of the S0-S1 transition in the DsRed protein using the polarizable embedding density functional theory formalism. We find that steric factors and chromophore-protein interactions act in concert to enhance the 2PA activity inside the protein while adversely blue-shifting the 1PA maximum. A two-state model reveals that the 2PA intensity gain is primarily governed by the increased change in the permanent dipole moment between the ground and the excited states acquired inside the protein. Our results indicate that this mainly is attributable to counter-directional contributions stemming from Lys163 and the conserved Arg95 with the former additionally identified as a key residue in the color tuning mechanism. The results provide new insight into the tuning mechanism of DsRed and suggest a possible strategy for simultaneous improvement of its 1PA and 2PA properties.
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Affiliation(s)
- Nanna H List
- †Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Jógvan Magnus H Olsen
- †Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Hans Jørgen Aa Jensen
- †Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Arnfinn H Steindal
- ‡Centre of Theoretical and Computational Chemistry, Department of Chemistry, N-9037 Tromsø, Norway
| | - Jacob Kongsted
- †Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
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Ghosh D, Acharya A, Tiwari SC, Krylov AI. Toward understanding the redox properties of model chromophores from the green fluorescent protein family: an interplay between conjugation, resonance stabilization, and solvent effects. J Phys Chem B 2012; 116:12398-405. [PMID: 22978512 DOI: 10.1021/jp305022t] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The redox properties of model chromophores from the green fluorescent protein family are characterized computationally using density functional theory with a long-range corrected functional, the equation-of-motion coupled-cluster method, and implicit solvation models. The analysis of electron-donating abilities of the chromophores reveals an intricate interplay between the size of the chromophore, conjugation, resonance stabilization, presence of heteroatoms, and solvent effects. Our best estimates of the gas-phase vertical/adiabatic detachment energies of the deprotonated (i.e., anionic) model red, green, and blue chromophores are 3.27/3.15, 2.79/2.67, and 2.75/2.35 eV, respectively. Vertical/adiabatic ionization energies of the respective protonated (i.e., neutral) species are 7.64/7.35, 7.38/7.15, and 7.70/7.32 eV, respectively. The standard reduction potentials (E(red)(0)) of the anionic (Chr•/Chr–) and neutral (Chr+•/Chr) model chromophores in acetonitrile are 0.34/1.40 V (red), 0.22/1.24 V (green), and −0.12/1.02 V (blue), suggesting, counterintuitively, that the red chromophore is more difficult to oxidize than the green and blue ones (in both neutral and deprotonated forms). The respective redox potentials in water follow a similar trend but are more positive than the acetonitrile values.
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Affiliation(s)
- Debashree Ghosh
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
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Bravaya KB, Grigorenko BL, Nemukhin AV, Krylov AI. Quantum chemistry behind bioimaging: insights from ab initio studies of fluorescent proteins and their chromophores. Acc Chem Res 2012; 45:265-75. [PMID: 21882809 DOI: 10.1021/ar2001556] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The unique properties of green fluorescent protein (GFP) have been harnessed in a variety of bioimaging techniques, revolutionizing many areas of the life sciences. Molecular-level understanding of the underlying photophysics provides an advantage in the design of new fluorescent proteins (FPs) with improved properties; however, because of its complexity, many aspects of the GFP photocycle remain unknown. In this Account, we discuss computational studies of FPs and their chromophores that provide qualitative insights into mechanistic details of their photocycle and the structural basis for their optical properties. In a reductionist framework, studies of well-defined model systems (such as isolated chromophores) help to understand their intrinsic properties, while calculations including protein matrix and/or solvent demonstrate, on the atomic level, how these properties are modulated by the environment. An interesting feature of several anionic FP chromophores in the gas phase is their low electron detachment energy. For example, the bright excited ππ* state of the model GFP chromophore (2.6 eV) lies above the electron detachment continuum (2.5 eV). Thus, the excited state is metastable with respect to electron detachment. This autoionizing character needs to be taken into account in interpreting gas-phase measurements and is very difficult to describe computationally. Solvation (and even microsolvation by a single water molecule) stabilizes the anionic states enough such that the resonance excited state becomes bound. However, even in stabilizing environments (such as protein or solution), the anionic chromophores have relatively low oxidation potentials and can act as light-induced electron donors. Protein appears to affect excitation energies very little (<0.1 eV), but alters ionization or electron detachment energies by several electron volts. Solvents (especially polar ones) have a pronounced effect on the chromophore's electronic states; for example, the absorption wavelength changes considerably, the ground-state barrier for cis-trans isomerization is reduced, and fluorescence quantum yield drops dramatically. Calculations reveal that these effects can be explained in terms of electrostatic interactions and polarization, as well as specific interactions such as hydrogen bonding. The availability of efficient computer implementations of predictive electronic structure methods is essential. Important challenges include developing faster codes (to enable better equilibrium sampling and excited-state dynamics modeling), creating algorithms for properties calculations (such as nonlinear optical properties), extending standard excited-state methods to autoionizing (resonance) states, and developing accurate QM/MM schemes. The results of sophisticated first-principle calculations can be interpreted in terms of simpler, qualitative molecular orbital models to explain general trends. In particular, an essential feature of the anionic GFP chromophore is an almost perfect resonance (mesomeric) interaction between two Lewis structures, giving rise to charge delocalization, bond-order scrambling, and, most importantly, allylic frontier molecular orbitals spanning the methine bridge. We demonstrate that a three-center Hückel-like model provides a useful framework for understanding properties of FPs. It can explain changes in absorption wavelength upon protonation or other structural modifications of the chromophore, the magnitude of transition dipole moment, barriers to isomerization, and even non-Condon effects in one- and two-photon absorption.
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Affiliation(s)
- Ksenia B. Bravaya
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Bella L. Grigorenko
- Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow 119991, Russia
| | - Alexander V. Nemukhin
- Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow 119991, Russia
- N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow 119334, Russia
| | - Anna I. Krylov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
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YAN WEIZHONG, XIE DAIQIAN, ZENG JUN. PROTONATION STATES AND CONFORMATIONAL FLEXIBILITY OF THE RED FLUORESCENT PROTEIN CHROMOPHORE. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s0219633609005362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Fluorescent proteins are important reporter molecules widely used in biotechnology and the biological sciences, generally. Their unusual spectrophotometric and fluorescence characteristics are controlled via protonation states of the chromophore, as for green fluorescent proteins (GFPs), and/or via cis–trans isomerization of the chromophore, as for red fluorescent proteins (RFPs). Here, we have performed both quantum mechanical calculations on substituted chromophores and structural comparisons of several RFPs (Rtms5, eqFP611, HcRed, and DsRed) and wild-type GFP. Our results indicate that the chromophore cis and trans isomers are comparably stable, and cis–trans isomerization has only a minor effect on electronic excitation. The chromophore is also found to exist in either the anionic or possibly zwitterionic protonation state. Structural comparisons of RFPs reveal that the conformation of the chromophore within a specific RFP is determined by only a few key residues, which could serve as mutation targets for engineering new fluorescent proteins for novel biotechnological applications.
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Affiliation(s)
- WEIZHONG YAN
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China
| | - DAIQIAN XIE
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China
| | - JUN ZENG
- Department of Chemistry, Sichuan University, Chengdu 610062, P. R. China
- MedChemSoft Solutions, 17 Joelson Avenue, Scoresby, Victoria 3179, Australia
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Huang A, Dou W, Caro J. Steam-Stable Zeolitic Imidazolate Framework ZIF-90 Membrane with Hydrogen Selectivity through Covalent Functionalization. J Am Chem Soc 2010; 132:15562-4. [DOI: 10.1021/ja108774v] [Citation(s) in RCA: 442] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Aisheng Huang
- Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Callinstr. 3A, D-30167 Hannover, Germany and Department of Chemistry, Lanzhou University, Lanzhou 730000, P. R. China
| | - Wei Dou
- Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Callinstr. 3A, D-30167 Hannover, Germany and Department of Chemistry, Lanzhou University, Lanzhou 730000, P. R. China
| | - Jürgen Caro
- Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Callinstr. 3A, D-30167 Hannover, Germany and Department of Chemistry, Lanzhou University, Lanzhou 730000, P. R. China
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11
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Venna SR, Carreon MA. Highly Permeable Zeolite Imidazolate Framework-8 Membranes for CO2/CH4 Separation. J Am Chem Soc 2009; 132:76-8. [DOI: 10.1021/ja909263x] [Citation(s) in RCA: 802] [Impact Index Per Article: 53.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Surendar R. Venna
- Department of Chemical Engineering, University of Louisville, Louisville, KY-40292
| | - Moises A. Carreon
- Department of Chemical Engineering, University of Louisville, Louisville, KY-40292
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12
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Sanchez-Garcia E, Doerr M, Hsiao YW, Thiel W. QM/MM Study of the Monomeric Red Fluorescent Protein DsRed.M1. J Phys Chem B 2009; 113:16622-31. [DOI: 10.1021/jp9069042] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
| | - Markus Doerr
- Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr
| | - Ya-Wen Hsiao
- Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr
| | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr
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13
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Liu Y, Ding J, Liu R, Shi D, Sun J. Time-dependent density functional theory study on the electronic excited-state geometric structure, infrared spectra, and hydrogen bonding of a doubly hydrogen-bonded complex. J Comput Chem 2009; 30:2723-7. [DOI: 10.1002/jcc.21297] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Drobizhev M, Tillo S, Makarov NS, Hughes TE, Rebane A. Color hues in red fluorescent proteins are due to internal quadratic Stark effect. J Phys Chem B 2009; 113:12860-4. [PMID: 19775174 PMCID: PMC2893592 DOI: 10.1021/jp907085p] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Intrinsically fluorescent proteins (FPs) exhibit broad variations of absorption and emission colors and are available for different imaging applications. The physical cause of the absorption wavelength change from 540 to 590 nm in the Fruits series of red FPs has been puzzling because the mutations that cause the shifts do not disturb the pi-conjugation pathway of the chromophore. Here, we use two-photon absorption measurements to show that the different colors can be explained by quadratic Stark effect due to variations of the strong electric field within the beta barrel. This model brings simplicity to a bewildering diversity of fluorescent protein properties, and it suggests a new way to sense electrical fields in biological systems.
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Yan W, Xie D, Zeng J. The 559-to-600 nm shift observed in red fluorescent protein eqFP611 is attributed to cis-trans isomerization of the chromophore in an anionic protein pocket. Phys Chem Chem Phys 2009; 11:6042-50. [PMID: 19606312 DOI: 10.1039/b903544c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Fluorescent proteins are commonly used as molecular labels, noninvasive markers of gene expression, and reporters of environmental conditions in live cells. We investigate the structural and spectroscopic properties of the chromophore of a far-red fluorescent protein eqFP611. Both the cis and trans isomers of the chromophore are examined within the protein for which both anionic and neutral states of protonation are considered. Spectroscopic properties are examined using time-dependent density functional theory (TDDFT), employing the B3LYP, PBE and B3PW91 density functionals. Intermolecular and long-range contributions to the structure and spectroscopy were treated using the own n-layered integrated molecular orbital and molecular mechanics (ONIOM) approach. The results indicated that the chromophore before excitation is in an anionic, protonated state, with the long-range contributions inducing a blue shift in the absorption and fluorescence maxima of the chromophore. Moreover, the calculated changes of the lowest pi-pi* excitation energy upon isomerization match the observed shift from 559 to 600 nm in the absorption maximum of the system following prolonged irradiation. Furthermore, decomposition analysis of the electrostatic contributions from individual residues indicated that the interactions from four residues Arg92, Lys67, Glu145, and His197 to the chromophore play a key role in the absorption and fluorescence spectra of eqFP611, suggesting that mutations at these sites should provide very useful mechanistic information.
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Affiliation(s)
- Weizhong Yan
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
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Liu Y, Ding J, Shi D, Sun J. Time-Dependent Density Functional Theory Study on Electronically Excited States of Coumarin 102 Chromophore in Aniline Solvent: Reconsideration of the Electronic Excited-State Hydrogen-Bonding Dynamics. J Phys Chem A 2008; 112:6244-8. [DOI: 10.1021/jp8022919] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Yufang Liu
- Henan Normal University, Xinxiang 453007, China
| | - Junxia Ding
- Henan Normal University, Xinxiang 453007, China
| | - Deheng Shi
- Henan Normal University, Xinxiang 453007, China
| | - Jinfeng Sun
- Henan Normal University, Xinxiang 453007, China
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