| Project/Area Number |
16350016
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Physical chemistry
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| Research Institution | Institute for laser Technology (ILT) |
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Principal Investigator |
CHOSROWJAN Haik Institute for Laser Technology, Laser Bioscience Research Team, Assistant Chief Researcher, レーザーバイオ科学研究チーム, 副主任研究員 (70291036)
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| Co-Investigator(Kenkyū-buntansha) |
MATAGA Noboru Institute for Laser Technology, Laser Bioscience Research Team, Team Leader, レーザーバイオ科学研究チーム, チームリーダー (30029368)
TANIGUCHI Seiji Institute for Laser Technology, Laser Bioscience Research Team, Researcher, レーザーバイオ科学研究チーム, 研究員 (00342725)
IMAMOTO Yasushi Nara Institute of Science and Technology, Graduate School of Materials Science, Assistant Professor, 物質創成科学研究科, 助教授 (80263200)
UNNO Masashi Saga University, Institute for Multidisciplinary Research for Advanced Materials, Assistant Professor, 理工学部機能物質化学科, 助教授 (50255428)
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| Project Period (FY) |
2004 – 2006
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| Project Status |
Completed (Fiscal Year 2006)
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| Budget Amount *help |
¥11,200,000 (Direct Cost: ¥11,200,000)
Fiscal Year 2006: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2005: ¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 2004: ¥7,500,000 (Direct Cost: ¥7,500,000)
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| Keywords | Fluorescence Up-Conversion / Time-Resolved Microscopy / Coherent Vibrations / Photoactive Yellow Protein (PYP) / FMN Binding Protein / Protein Single Crystals / Femtosecond Photoisomerization / Light Induced Electron Transfer / フェムト秒ダイナミクス / 光異性化反応 / 顕微分光 / ラマン分光 |
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| Research Abstract |
The purpose of this project was to construct a space-resolved fluorescence up-conversion apparatus and study dynamics and micro-Raman scattering spectra of protein crystals in comparison with solution dynamics.
Three different versions of the system have been tested. Main specifications of the best configuration were : <200fs time-,<2μm space-resolution, excitation power <5μW, spectral range 400-750nm. Wavelength and polarization dependent experiments on native and R52Q mutant PYP crystals have been performed. Decays were similar to those measured in solution. This indicates that there are no essential differences between PYP's initial dark-structure in solution and crystals.
We have performed resonance Raman scattering experiments on PYP solutions and micro-Raman measurements on PYP single crystals. The spectra of crystal samples were similar to the Raman spectrum of the PYP solution, confirming our conclusion about the similarity of the PYP initial dark-states in solution and crystals.
… More
The second goal was to identify low-frequency intra-chromophore vibrations and study their role in primary photoisomerization reactions of native, mutant and analogue PYP systems. It was found that two modes (〜50cm^<-1> and〜140cm^<-1>) couple to the fluorescence decay. Those modes coherently "trigger" and "guide" the photoisomerization reaction.
Fluorescence anisotropy of native PYP, seven mutants and three analogues have been measured. Ultrafast transient absorption experiments on native PYP and T50V,E46Q,R52Q mutants in solution have been performed.
Ab initio MO (DFT) calculations on Locked Chromophore analogue were performed and compared with native PYP. New PYP model chromophores (TMpCA,TML,TML rot-lock) and rot-lock PYP analogue have been studied.
Our new system has been applied to FMN binding protein crystals. We have observed qualitatively different dynamics in crystals contrasting their dynamics in solution.
Using new apparatus, excitation spot dependent spectral distribution and dynamics of MG micro-particles fluorescence has been studied. We concluded that in MG particles three ground-state isomers exist. Less
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