Updated on 2026/07/02

写真a

 
KAWAI KIYOHIKO
 
Organization
School of Life Science and Technology Professor
Title
Professor
Profile
「生命に関わる化学反応を速度定数まで紐解き理解し、速度定数の測定に基づく分析法や診断法の開発を目指しています」
速度定数を求めることを、生命のしくみの理解、病気の診断法の開発へとそのまま直結できるようにするため、1分子蛍光観測による測定法の開発を展開しています。速度定数を勘案した分子設計に基づいて、様々な生体材料の開発を目指しています。光・放射線をトリガーとした生体分子の構造変化の時間制御にも取り組んでいます。
External link

Degree

  • (BLANK) ( Kyoto University )

Research Interests

  • 生物有機化学

  • 放射線化学

  • 光化学

  • Photochemistry

  • Bioorganic Chemistry

  • Radiation Chemistry

  • Single molecule detection

  • Nucleic Acids Chemistry

Research Areas

  • Nanotechnology/Materials / Synthetic organic chemistry

  • Nanotechnology/Materials / Fundamental physical chemistry

  • Life Science / Bioorganic chemistry

  • Nanotechnology/Materials / Structural organic chemistry and physical organic chemistry

Education

  • Kyoto University   Graduate School, Division of Engineering

    - 1999

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  • Kyoto University

    - 1999

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    Country: Japan

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  • Kyoto University   Faculty of Engineering

    - 1994

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  • Kyoto University   Faculty of Engineering

    - 1994

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    Country: Japan

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Research History

  • Institute of Science Tokyo   Department of Life Science and Technology

    2024.10

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    Country:Japan

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  • Tokyo Institute of Technology   School of Life Science and Technology   Professor

    2023.1 - 2024.9

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  • KU-Leuven / imec (Belgium)   Visiting Associate Professor

    2017.9 - 2018.8

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  • 科学技術振興機構   さきがけ研究員(兼任)

    2013.10 - 2017.3

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  • Osaka University   Associate Professor

    2006.4 - 2022.12

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  • Simon Fraser University (Canada)   Visiting Associate Professor

    2006.1 - 2006.3

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  • Osaka University

    2005.10 - 2006.3

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  • Osaka University   Research Associate

    1999.4 - 2005.9

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  • 学術振興会特別研究員

    1996 - 1999

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Professional Memberships

Committee Memberships

  •   Associate Editor, J. Photochem. Photobiol. C. Photochem. Rev.  

    2021 - 2022   

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  • 日本核酸化学会   評議員  

    2017.11   

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    Committee type:Academic society

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  • 日本光医学・光生物学会   第33回日本光医学・光生物学会 事務局長  

    2011   

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  • 日本化学会   第90春季年会プログラム編成委員  

    2010   

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  • 新世代の生物有機化学研究会   新世代の生物有機化学研究会2008 開催会場責任者  

    2008   

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  • 日本化学会   第87春季年会プログラム編成委員  

    2007   

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Papers

  • Hidden Markov model analysis of fluorescence blinking in fluorescently labeled DNA Reviewed

    Tatsuhiro Furuta, Shuya Fan, Tadao Takada, Yohei Kondo, Mamoru Fujitsuka, Atsushi Maruyama, Kiyohiko Kawai, Kazuma Nakamura

    Scientific Reports   2026.2

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    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

    DOI: 10.1038/s41598-026-40876-x

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  • Molecular beacon strategies that control the generation of singlet oxygen via intramolecular energy transfer between a ruthenium photosensitizer and COT quencher on oligodeoxynucleotides Reviewed

    Sae Harada, Daisuke Mochizuki, Kazuki Iwasawa, Tatsuya Nishihara, Kiyohiko Kawai, Yasuko Osakada, Mamoru Fujitsuka, Kazuhito Tanabe

    Chemistry Letters   55 ( 2 )   2026.2

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    Publishing type:Research paper (scientific journal)   Publisher:Oxford University Press (OUP)  

    Abstract

    A molecular beacon-based platform that enables the switchable, DNA-structure-dependent generation of singlet oxygen ( 1O2) was designed. We prepared stem-and-loop structured oligodeoxynucleotides with an excellent photosensitizer, ruthenium complex, and cyclooctatetraene quencher attached at each strand end. The stem-and-loop structured oligodeoxynucleotides suppressed the photosensitized generation of  1O2 from the ruthenium photosensitizer owing to intramolecular quenching by the quencher located near the chromophore. Strikingly, hybridization with its complementary strand triggered a stem-and-loop to duplex transition that spatially separated the photosensitizer and quencher, thereby unleashing  1O2 generation upon photoirradiation. The duplex form showed strong cytotoxic effects owing to the efficient generation of  1O2. Thus, the structural change of DNA could regulate the generation of  1O2 and the following cytotoxic effects.

    DOI: 10.1093/chemle/upag024

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  • Methoxy-Substituted Perylenediimide-Modified DNA for Enhanced Fluorescent Probes and Single-Nucleotide Discrimination. Reviewed International journal

    Tadao Takada, Ami Takata, Yuna Yamamoto, Mitsunobu Nakamura, Mamoru Fujitsuka, Kiyohiko Kawai, Kazushige Yamana

    The journal of physical chemistry. B   129 ( 26 )   6498 - 6504   2025.7

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    Artificial DNA molecules functionalized with fluorescent dyes are useful for developing fluorescent chemosensors and molecular imaging tools. Fluorescent nucleic acids have been developed based on the excellent fluorescent properties of perylenediimide (PDI); however, the electron transfer quenching of PDI by purine bases limits the sequence design of fluorescent probes. In this study, to compensate for the disadvantages of PDI due to electron transfer quenching, we used PDI with a methoxy group introduced into the perylene ring (PO), synthesized PO-substituted nucleic acids, and investigated their fluorescence properties. The results showed that PO in the DNA exhibited longer-wavelength fluorescence than unsubstituted PDI and displayed strong fluorescence when surrounded by AT base pairs. We also found that PO exhibits a fluorescence on-off response to the hybridization reaction and selective quenching by guanine bases in the vicinity of PO, which could be applied to fluorescent biosensors for single nucleotide identification and nucleic acid detection. Because of the high photostability of PO, single-molecule measurements were feasible, allowing confirmation of PO's fluorescence switching behavior of PO in response to DNA conformational changes and the presence of guanine bases at the single-molecule level using fluorescence correlation spectroscopy (FCS).

    DOI: 10.1021/acs.jpcb.5c02912

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  • Sensing the Concentration of Biological Reductants through Single-Molecule Fluorescence Blinking Reviewed

    Yohei Kondo, Shotaro Tsuchitori, Yuki Yonezawa, Tadao Takada, Atsushi Maruyama, Mamoru Fujitsuka, Kiyohiko Kawai

    The Journal of Physical Chemistry Letters   5202 - 5207   2025.5

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    Authorship:Last author, Corresponding author   Publishing type:Research paper (scientific journal)   Publisher:American Chemical Society (ACS)  

    DOI: 10.1021/acs.jpclett.5c00475

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  • 物質科学動的データに対する機械学習解析 Reviewed

    中村 和磨, 小田 勝, 川井 清彦

    化学と教育   72 ( 11 )   460 - 462   2024.11

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    Authorship:Last author   Language:Japanese   Publishing type:Research paper (scientific journal)  

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  • Programmed Control of Fluorescence Blinking Patterns based on Electron Transfer in DNA

    Shuya Fan, Tadao Takada, Atsushi Maruyama, Mamoru Fujitsuka, Kiyohiko Kawai

    Chemistry – A European Journal   29 ( 19 )   2023.2

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    Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    Abstract

    Fluorescence imaging uses changes in the fluorescence intensity and emission wavelength to analyze multiple targets simultaneously. To increase the number of targets that can be identified simultaneously, fluorescence blinking can be used as an additional parameter. To understand and eventually control blinking, we used DNA as a platform to elucidate the processes of electron transfer (ET) leading to blinking, down to the rate constants. With a fixed ET distance, various blinking patterns were observed depending on the DNA sequence between the donor and acceptor units of the DNA platform. The blinking pattern was successfully described with a combination of ET rate constants. Therefore, molecules with various blinking patterns can be developed by tuning ET. It is expected that the number of targets that can be analyzed simultaneously will increase by the power of the number of blinking patterns.

    DOI: 10.1002/chem.202203552

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    Other Link: https://onlinelibrary.wiley.com/doi/full-xml/10.1002/chem.202203552

  • Red, green, and blue radio-luminescent polymer dots doped with heteroleptic tris-cyclometalated iridium complexes

    Zouyue Liu, Hieu Thi Minh Nguyen, Daiki Asanuma, Sachiko Tojo, Minoru Yamaji, Kiyohiko Kawai, Guillem Pratx, Mamoru Fujitsuka, Yasuko Osakada

    RSC Advances   13 ( 22 )   15126 - 15131   2023

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    Publishing type:Research paper (scientific journal)   Publisher:Royal Society of Chemistry (RSC)  

    In this study, we synthesized radioexcitable luminescent polymer dots (P-dots) doped with heteroleptic tris-cyclometalated iridium complexes that emit red, green, and blue light.

    DOI: 10.1039/d3ra01216f

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  • Radioluminescence from polymer dots based on thermally activated delayed fluorescence

    Daiki Asanuma, Hieu T Nguyen, Zuoyue Liu, Sachiko Tojo, Hajime Shigemitsu, Minoru Yamaji, Kiyohiko Kawai, Tadashi Mori, Toshiyuki Kida, Guillem Pratx, Mamoru Fujitsuka, Yasuko Osakada

    Nanoscale Advances   2023

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    Publishing type:Research paper (scientific journal)   Publisher:Royal Society of Chemistry (RSC)  

    We demonstrate that polymer dots doped with thermally activated delayed fluorescence (TADF) molecules clearly exhibit blue radio-luminescence upon hard X-ray and electron beam irradiation, which is a new design for...

    DOI: 10.1039/d3na00308f

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  • Large heterogeneity observed in single molecule measurements of intramolecular electron transfer rates through DNA

    Shuya Fan, Tadao Takada, Atsushi Maruyama, Mamoru Fujitsuka, Kiyohiko Kawai

    Bulletin of the Chemical Society of Japan   95 ( 12 )   1697 - 1702   2022.12

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    Publishing type:Research paper (scientific journal)  

    DOI: 10.1246/bcsj.20220220

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  • Electron-transfer kinetics through nucleic acids untangled by single-molecular fluorescence blinking

    Shuya Fan, Jie Xu, Yasuko Osakada, Katsunori Hashimoto, Kazuya Takayama, Atsushi Natsume, Masaki Hirano, Atsushi Maruyama, Mamoru Fujitsuka, Kumi Kawai, Kiyohiko Kawai

    Chem   8 ( 11 )   3109 - 3119   2022.11

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier BV  

    DOI: 10.1016/j.chempr.2022.07.025

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  • Stacked Thiazole Orange Dyes in DNA Capable of Switching Emissive Behavior in Response to Structural Transitions

    Tadao Takada, Koma Nishida, Yurika Honda, Aoi Nakano, Mitsunobu Nakamura, Shuya Fan, Kiyohiko Kawai, Mamoru Fujitsuka, Kazushige Yamana

    ChemBioChem   22 ( 17 )   2729 - 2735   2021.9

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    Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    DOI: 10.1002/cbic.202100309

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    Other Link: https://onlinelibrary.wiley.com/doi/full-xml/10.1002/cbic.202100309

  • COF-based photocatalyst for energy and environment applications Reviewed

    Xinxi Li, Kiyohiko Kawai, Mamoru Fujitsuka, Yasuko Osakada

    Surfaces and Interfaces   25   101249 - 101249   2021.8

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier {BV}  

    DOI: 10.1016/j.surfin.2021.101249

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  • Control of Triplet Blinking Using Cyclooctatetraene to Access the Dynamics of Biomolecules at the Single‐Molecule Level

    Jie Xu, Shuya Fan, Lei Xu, Atsushi Maruyama, Mamoru Fujitsuka, Kiyohiko Kawai

    Angewandte Chemie International Edition   60 ( 23 )   12941 - 12948   2021.6

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    Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    DOI: 10.1002/anie.202101606

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    Other Link: https://onlinelibrary.wiley.com/doi/full-xml/10.1002/anie.202101606

  • Single-Molecule Study of Redox Reaction Kinetics by Observing Fluorescence Blinking

    Kiyohiko Kawai, Mamoru Fujitsuka, Atsushi Maruyama

    Accounts of Chemical Research   54 ( 4 )   1001 - 1010   2021.2

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:American Chemical Society  

    DOI: 10.1021/acs.accounts.0c00754

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  • Dynamics of Single‐Stranded RNA Looping Probed and Photoregulated by Sulfonated Pyrene

    Jie Xu, Sachiko Tojo, Mamoru Fujitsuka, Kiyohiko Kawai

    ChemistrySelect   5 ( 26 )   8002 - 8008   2020.7

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    Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    DOI: 10.1002/slct.202002231

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    Other Link: https://onlinelibrary.wiley.com/doi/full-xml/10.1002/slct.202002231

  • Sulfonated Pyrene as a Photoregulator for Single-Stranded DNA Looping

    Jie Xu, Shunichi Miyamoto, Sachiko Tojo, Kiyohiko Kawai

    Chemistry - A European Journal   26 ( 22 )   5075 - 5084   2020.4

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley-VCH Verlag  

    DOI: 10.1002/chem.202000184

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  • Fluorescence Redox Blinking Adaptable to Structural Analysis of Nucleic Acids Reviewed

    Takafumi Miyata, Naohiko Shimada, Atsushi Maruyama, Kiyohiko Kawai

    Chemistry - A European Journal   24 ( 26 )   6755 - 6761   2018.5

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley-VCH Verlag  

    DOI: 10.1002/chem.201705668

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    Other Link: http://orcid.org/0000-0001-6845-0663

  • Single-Molecule Monitoring of the Structural Switching Dynamics of Nucleic Acids through Controlling Fluorescence Blinking Reviewed

    Kiyohiko Kawai, Takafumi Miyata, Naohiko Shimada, Syoji Ito, Hiroshi Miyasaka, Atsushi Maruyama

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   56 ( 48 )   15329 - 15333   2017.11

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/anie.201708705

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    Other Link: http://orcid.org/0000-0001-6845-0663

  • Single-Molecule Monitoring of the Structural Switching Dynamics of Nucleic Acids through Controlling Fluorescence Blinking Reviewed

    Kiyohiko Kawai, Takafumi Miyata, Naohiko Shimada, Syoji Ito, Hiroshi Miyasaka, Atsushi Maruyama

    Angewandte Chemie   129 ( 48 )   15531   2017.11

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    Publisher:Wiley-Blackwell  

    DOI: 10.1002/ange.201708705

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  • BODIPY-labeled Fluorescent Aptamer Sensors for Turn-on Sensing of Interferon-gamma and Adenine Compounds on Cells Reviewed

    Akira Tsuchiya, Siti N. Hashim, Shoko Ise, Takafumi Furuhata, Kiyohiko Kawai, Rie Wakabayashi, Masahiro Goto, Noriho Kamiya, Shinsuke Sando

    ANALYTICAL SCIENCES   32 ( 5 )   543 - 547   2016.5

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    DOI: 10.2116/analsci.32.543

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  • DNA Microenvironment Monitored by Controlling Redox Blinking Reviewed

    Kiyohiko Kawai, Kenji Higashiguchi, Atsushi Maruyama, Tetsuro Majima

    CHEMPHYSCHEM   16 ( 17 )   3590 - 3594   2015.12

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/cphc.201500793

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  • Photocurrent Generation through Charge-Transfer Processes in Noncovalent Perylenediimide/DNA Complexes Reviewed

    Tadao Takada, Misa Ido, Akane Ashida, Mitsunobu Nakamura, Mamoru Fujitsuka, Kiyohiko Kawai, Tetsuro Majima, Kazushige Yamana

    CHEMISTRY-A EUROPEAN JOURNAL   21 ( 18 )   6846 - 6851   2015.4

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    DOI: 10.1002/chem.201406592

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  • Increasing the Hole Transfer Rate Through DNA by Chemical Modification Reviewed

    Kiyohiko Kawai, Tetsuro Majima

    Chemical Science of Electron Systems   751 - 760   2015.1

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    DOI: 10.1007/978-4-431-55357-1_44

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  • Photoinduced Charge-Separation in DNA Reviewed

    Kiyohiko Kawai, Tetsuro Majima

    PHOTOINDUCED PHENOMENA IN NUCLEIC ACIDS II: DNA FRAGMENTS AND PHENOMENOLOGICAL ASPECTS   356   165 - 182   2015

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    DOI: 10.1007/128_2013_525

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  • Triple helix conformation-specific blinking of Cy3 in DNA Reviewed

    Kiyohiko Kawai, Atsushi Maruyama

    CHEMICAL COMMUNICATIONS   51 ( 23 )   4861 - 4864   2015

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c5cc00607d

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  • Blinking triggered by the change in the solvent accessibility of a fluorescent molecule Reviewed

    Kiyohiko Kawai, Takeshi Koshimo, Atsushi Maruyama, Tetsuro Majima

    CHEMICAL COMMUNICATIONS   50 ( 72 )   10478 - 10481   2014

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    DOI: 10.1039/c4cc00377b

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  • Hole Transfer Kinetics of DNA Reviewed

    Kiyohiko Kawai, Tetsuro Majima

    ACCOUNTS OF CHEMICAL RESEARCH   46 ( 11 )   2616 - 2625   2013.11

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  • Detection of Single-Nucleotide Variations by Monitoring the Blinking of Fluorescence Induced by Charge Transfer in DNA Reviewed

    Kiyohiko Kawai, Tetsuro Majima, Atsushi Maruyama

    CHEMBIOCHEM   14 ( 12 )   1430 - 1433   2013.8

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/cbic.201300380

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  • Synthesis and charge transferability of DNA possessing a naphthalimide photosensitizer at an extrahelical position Reviewed

    Tadao Takada, Yuta Kawano, Akane Ashida, Mitsunobu Nakamura, Kiyohiko Kawai, Tetsuro Majima, Kazushige Yamana

    TETRAHEDRON LETTERS   54 ( 35 )   4796 - 4799   2013.8

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    DOI: 10.1016/j.tetlet.2013.06.140

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  • Kinetics of charge transfer through DNA across guaninecytosine repeats intervened by adeninethymine Base Pair(s) Reviewed

    Yasuko Osakada, Kiyohiko Kawai, Tetsuro Majima

    Bulletin of the Chemical Society of Japan   86 ( 1 )   25 - 30   2013

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    DOI: 10.1246/bcsj.20120224

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  • Excess-Electron Injection and Transfer in Terthiophene-Modified DNA: Terthiophene as a Photosensitizing Electron Donor for Thymine, Cytosine,and Adenine (vol 18, pg 2056, 2012) Reviewed

    M.J. Park, M. Fujitsuka, K. Kawai, T. Majima

    CHEMISTRY-A EUROPEAN JOURNAL   18 ( 24 )   7326 - 7326   2012.6

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  • Hole Transfer in LNA and 5-Me-2 '-deoxyzebularine-Modified DNA Reviewed

    Kiyohiko Kawai, Mitsuo Hayashi, Tetsuro Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   134 ( 22 )   9406 - 9409   2012.6

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    DOI: 10.1021/ja302641e

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  • HOMO Energy Gap Dependence of Hole-Transfer Kinetics in DNA Reviewed

    Kiyohiko Kawai, Mitsuo Hayashi, Tetsuro Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   134 ( 10 )   4806 - 4811   2012.3

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    DOI: 10.1021/ja2109213

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  • Excess-Electron Injection and Transfer in Terthiophene-Modified DNA: Terthiophene as a Photosensitizing Electron Donor for Thymine, Cytosine, and Adenine Reviewed

    Man Jae Park, Mamoru Fujitsuka, Kiyohiko Kawai, Tetsuro Majima

    CHEMISTRY-A EUROPEAN JOURNAL   18 ( 7 )   2056 - 2062   2012.2

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    DOI: 10.1002/chem.201103663

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  • Generation of Singlet Oxygen during Photosensitized One-Electron Oxidation of DNA Reviewed

    Yasuko Osakada, Kiyohiko Kawai, Takashi Tachikawa, Mamoru Fujitsuka, Kazuki Tainaka, Shozo Tero-Kubota, Tetsuro Majima

    CHEMISTRY-A EUROPEAN JOURNAL   18 ( 4 )   1060 - 1063   2012.1

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    DOI: 10.1002/chem.201101964

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  • Excess electron transfer dynamics in DNA hairpins conjugated with N,N-dimethylaminopyrene as a photosensitizing electron donor Reviewed

    Man Jae Park, Mamoru Fujitsuka, Haruhiro Nishitera, Kiyohiko Kawai, Tetsuro Majima

    CHEMICAL COMMUNICATIONS   48 ( 89 )   11008 - 11010   2012

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c2cc36054c

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  • Direct Measurement of the Dynamics of Excess Electron Transfer through Consecutive Thymine Sequence in DNA Reviewed

    Man Jae Park, Mamoru Fujitsuka, Kiyohiko Kawai, Tetsuro Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   133 ( 39 )   15320 - 15323   2011.10

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    DOI: 10.1021/ja2068017

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  • Probing the Charge-Transfer Dynamics in DNA at the Single-Molecule Level Reviewed

    Kiyohiko Kawai, Eri Matsutani, Atsushi Maruyama, Tetsuro Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   133 ( 39 )   15568 - 15577   2011.10

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    DOI: 10.1021/ja206325m

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  • G-C Content Independent Long-Range Charge Transfer Through DNA Reviewed

    Kiyohiko Kawai, Tetsuro Majima

    ELECTRONIC AND MAGNETIC PROPERTIES OF CHIRAL MOLECULES AND SUPRAMOLECULAR ARCHITECTURES   298   129 - 142   2011

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    Language:English   Publishing type:Part of collection (book)  

    DOI: 10.1007/128_2010_90

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  • Sequence Dependence of Excess Electron Transfer in DNA Reviewed

    Kazuki Tainaka, Mamoru Fujitsuka, Tadao Takada, Kiyohiko Kawai, Tetsuro Majima

    JOURNAL OF PHYSICAL CHEMISTRY B   114 ( 45 )   14657 - 14663   2010.11

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/jp1024685

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  • Photocatalytic Formation of I-I Bonds Using DNA Which Enables Detection of Single Nucleotide Polymorphisms Reviewed

    Kiyohiko Kawai, Haruka Kodera, Tetsuro Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   132 ( 40 )   14216 - 14220   2010.10

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    DOI: 10.1021/ja105850d

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  • Charge Separation and Photosensitized Damage in DNA Mediated by Naphthalimide, Naphthaldiimide, and Anthraquinone Reviewed

    Kiyohiko Kawai, Yasuko Osakada, Eri Matsutani, Tetsuro Majima

    JOURNAL OF PHYSICAL CHEMISTRY B   114 ( 31 )   10195 - 10199   2010.8

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/jp102483k

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  • 8-Oxo-7,8-dihydro-2 '-deoxyguanosine produces a long-lived charge-separated state during the photosensitized one-electron oxidation of DNA resulting in efficient and exclusive degradation Reviewed

    Kiyohiko Kawai, Eri Matsutani, Tetsuro Majima

    CHEMICAL COMMUNICATIONS   46 ( 19 )   3277 - 3279   2010

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c002810j

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  • Kinetics of Long-Range Oxidative Electron Transfer through DNA Reviewed

    Kiyohiko Kawai, Tetsuro Majima

    Radical and Radical Ion Reactivity in Nucleic Acid Chemistry   191 - 210   2009.9

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    Language:English   Publishing type:Part of collection (book)   Publisher:John Wiley & Sons, Inc.  

    DOI: 10.1002/9780470526279.ch7

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  • Importance of Protonation State of Guanine Radical Cation During Hole Transfer in DNA Reviewed

    Kiyohiko Kawai, Yasuko Osakada, Tetsuro Majima

    CHEMPHYSCHEM   10 ( 11 )   1766 - 1769   2009.8

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/cphc.200900148

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  • Sequence-independent and rapid long-range charge transfer through DNA Reviewed

    Kiyohiko Kawai, Haruka Kodera, Yasuko Osakada, Tetsuro Majima

    NATURE CHEMISTRY   1 ( 2 )   156 - 159   2009.5

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    DOI: 10.1038/NCHEM.171

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  • Charge transfer in DNA assemblies: effects of sticky ends Reviewed

    Yasuko Osakada, Kiyohiko Kawai, Mamoru Fujitsuka, Tetsuro Majima

    CHEMICAL COMMUNICATIONS   ( 23 )   2656 - 2658   2008

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    DOI: 10.1039/b801876f

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  • Charge transfer through DNA nanoscaled assembly programmable with DNA building blocks Reviewed

    Yasuko Osakada, Kiyohiko Kawai, Mamoru Fujitsuka, Tetsuro Majima

    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA   103 ( 48 )   18072 - 18076   2006.11

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    DOI: 10.1073/pnas.0607148103

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  • Rapid long-distance hole transfer through consecutive adenine sequence Reviewed

    Tadao Takada, Kiyohiko Kawai, Mamoru Fujitsuka, Tetsuro Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   128 ( 34 )   11012 - 11013   2006.8

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    DOI: 10.1021/ja0641554

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  • Probing the microenvironments in the grooves of Z-DNA using dan-modified oligonucleotides Reviewed

    T Kimura, K Kawai, T Majima

    CHEMICAL COMMUNICATIONS   ( 14 )   1542 - 1544   2006.4

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    DOI: 10.1039/b600026f

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  • Spectroscopic Investigation of Oxidative Hole Transfer via Adenine Hopping in DNA Reviewed

    Kiyohiko Kawai, Tetsuro Majima

    Charge Transfer in DNA: From Mechanism to Application   117 - 132   2006.2

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    DOI: 10.1002/3527606629.ch5

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  • Effects of reaction rate of radical anion of a photosensitizer with molecular oxygen on the photosensitized DNA damage Reviewed

    Kiyohiko Kawai, Yasuko Osakada, Mamoru Fujitsuka, Tetsuro Majima

    CHEMICAL COMMUNICATIONS   ( 37 )   3918 - 3920   2006

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    DOI: 10.1039/b608027h

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  • The mutant form of acetolactate synthase genomic DNA from rice is an efficient selectable marker for genetic transformation Reviewed

    K Osakabe, M Endo, K Kawai, Y Nishizawa, K Ono, K Abe, Y Ishikawa, H Nakamura, H Ichikawa, S Nishimura, T Shimizu, S Toki

    MOLECULAR BREEDING   16 ( 4 )   313 - 320   2005.11

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    DOI: 10.1007/s11032-005-0999-y

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  • Photosensitized one-electron oxidation of DNA Reviewed

    K Kawai, T Majima

    PURE AND APPLIED CHEMISTRY   77 ( 6 )   963 - 975   2005.6

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    DOI: 10.1351/pac200577060963

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  • Contributions of the distance-dependent reorganization energy and proton-transfer to the hole-transfer process in DNA Reviewed

    T Takada, K Kawai, M Fujitsuka, T Majima

    CHEMISTRY-A EUROPEAN JOURNAL   11 ( 13 )   3835 - 3842   2005.6

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    DOI: 10.1002/chem.20050052

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  • Stepwise photocleavage of C-O bonds of bis(substituted-methyl)naphthalenes with stepwise excitation by two-color two-laser and three-color three-laser irradiations. International journal

    Xichen Cai, Masanori Sakamoto, Michihiro Hara, Sachiko Tojo, Akihiko Ouchi, Akira Sugimoto, Kiyohiko Kawai, Masayuki Endo, Mamoru Fujitsuka, Tetsuro Majima

    The journal of physical chemistry. A   109 ( 17 )   3797 - 802   2005.5

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    Stepwise photocleavage of naphthylmethyl-oxygen (C-O) bonds of mono(substituted-methyl)naphthalenes [1- and 2-ROCH2Np, R = 4-benzoylphenyl (BP), phenyl (Ph), and methyl (CH3)] and bis(substituted-methyl)naphthalenes [1,8-(ROCH2)2Np and 1,4-(ROCH2)2Np, R = BP and Ph] was observed to give the naphthylmethyl radicals (NpCH2* or ROCH2NpCH2*) in almost 100% yield with two-step or three-step excitation by the two-color two-laser or three-color three-laser irradiation, respectively, at room temperature. The C-O bond cleavage quantum yields of 1-PhOCH2Np, 2-PhOCH2Np, 1,8-(PhOCH2)2Np, and 1,4-(PhOCH2)2Np were higher than those of 1-BPOCH2Np, 2-BPOCH2Np, 1,8-(BPOCH2)2Np, and 1,4-(BPOCH2)2Np. No C-O bond cleavage occurred from 1,8-(HOCH2)2Np and 2-CH3OCH2Np in the higher triplet excited state (T(n)). The experimental results show that the C-O bond cleavage was determined not only by the position of the substituents on Np but also by the type of the substituents. The C-O bond cleavage of 1-ROCH2Np was more efficient than that of 2-ROCH2Np. In the case of 1,8-(ROCH2)2Np and 1,4-(ROCH2)2Np (R = BP and Ph), the first C-O bond cleavage from the T(n) states occurred to give ROCH2-substituted naphthylmethyl radicals (1,8- and 1,4-ROCH2NpCH2*) when the T1 states, generated with the 308-nm first laser irradiation, were excited using the 430-nm second laser. The second C-O bond cleavage occurred when 1,8- and 1,4-ROCH2NpCH2* in the ground state [1,8- and 1,4-ROCH2NpCH2*(D0)] were excited to the excited states [1,8- and 1,4-ROCH2NpCH2*(D(n))] using the third 355-nm laser during the three-color three-laser flash photolysis at room temperature. It was revealed that acenaphthene was produced as the final product during the stepwise C-O bond cleavages of 1,8-(BPOCH2)2Np and 1,8-(PhOCH2)2Np. This is a successful example of stepwise cleavage of two equivalent C-O bonds in a molecule using the three-color three-laser photolysis method.

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  • Recognition of substituted cytosine derivatives by the base pairing with guanine connected to pyrene Reviewed

    Kawai, T, Ikegami, M, Kawai, K, Majima, T, Nishimura, Y, Arai, T

    CHEMICAL PHYSICS LETTERS   407 ( 1-3 )   58 - 62   2005.5

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    DOI: 10.1016/j.cplett.2005.03.057

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  • Dihydrophenanthrene-type intermediates during photoreaction of trans-4'-benzyl-5-styrylfuran. International journal

    Shingo Samori, Michihiro Hara, Tong-Ing Ho, Sachiko Tojo, Kiyohiko Kawai, Masayuki Endo, Mamoru Fujitsuka, Tetsuro Majima

    The Journal of organic chemistry   70 ( 7 )   2708 - 12   2005.4

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    [structure: see text] Photoreaction of trans-4'-benzyl-5-styrylfuran (trans-BSF) has been studied by the 355-nm laser flash photolysis (LFP) in CH2Cl2 using a Nd3+:YAG laser (30 ps, 5 mJ pulse(-1) or 5 ns, 30 mJ pulse(-1)). Transient fluorescence and absorption spectra assigned to the singlet excited trans-BSF were observed during the 30-ps LFP, whereas a transient absorption spectrum with two peaks at 400 and 510 nm, assigned to the trans-fused dihydrophenanthrene (DHP)-type intermediate (DP1), was observed during the 5-ns LFP. It is clearly suggested that a two-photon absorption process is involved in the formation of DP1. The first photoreaction is the photoisomerization of trans-BSF, which occurs to give cis-BSF. The second photoreaction process is photocyclization of cis-BSF, which occurs to give DP1 decaying with the half lifetime (tau1/2) of 2.8-4.0 micros to produce another DHP-type intermediate (DP2) with an absorption peak at 400 nm in the absence of O2, through [1,9]-hydrogen shift. DP2 decayed with tau1/2 > 500 micros to give the product through aromatization. In O2-saturated CH2Cl2, DP1 decayed with tau1/2 = 250 ns to give a radical intermediate (X) with two peaks at 410 and 510 nm, through hydrogen abstraction of DP1 by O2. X decayed with tau1/2 = 150 micros to give the product through successive hydrogen abstraction.

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  • Inhibition of the formation and decay of stilbene core radical cations by the dendron during the photoinduced electron transfer. International journal

    Michihiro Hara, Shingo Samori, Xichen Cai, Sachiko Tojo, Tatsuo Arai, Atsuya Momotake, Junpei Hayakawa, Mayuko Uda, Kiyohiko Kawai, Masayuki Endo, Mamoru Fujitsuka, Tetsuro Majima

    The journal of physical chemistry. B   109 ( 2 )   973 - 6   2005.1

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    Formation and decay processes of stilbene core radical cation (ST*+) during the photoinduced electron transfer have been studied for a series of stilbene bearing benzyl ether-type dendrons (D). ST*+ and the radical cation of peripheral dendron (D*+) were generated by intermolecular hole transfer from biphenyl radical cation, which was generated from photoinduced electron transfer from biphenyl to the singlet-excited 9,10-dicyanoanthracene in a mixture of acetonitrile and 1,2-dichloroethane (3:1). An intramolecular dimer radical cation of benzyl groups at the terminal of stilbene dendrimer was indicated as a hole trapping site. Subsequent hole transfer from the trapping site to the core ST generated ST*+. The shielding effects of D depending on the dendrimer generation on the growth and decay of ST*+ were observed. It was revealed for the first time that D acts as the hole trapping site and the hole conductor on the way of the exothermic hole transfer from the terminal of D to the central core ST. We also found that D inhibits the charge recombination with 9,10-dicyanoanthracene radical anion because of the steric hindrance.

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  • Homolytic cleavage of C-Si bond of p-trimethylsilylmethylacetophenone upon stepwise two-photon excitation using two-color two-laser flash photolysis Reviewed

    X. Cai, M. Sakamoto, M. Hara, S. Inomata, M. Yamaji, S. Tojo, K. Kawai, M. Endo, M. Fujitsuka, T. Majima

    Chemical Physics Letters   407 ( 4-6 )   402 - 406   2005

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  • Quenching processes of aromatic hydrocarbons in the higher triplet excited states-energy transfer vs. electron transfer Reviewed

    X. Cai, M. Sakamoto, M. Hara, S. Tojo, K. Kawai, M. Endo, M. Fujitsuka, T. Majima

    Physical Chemistry Chemical Physics   6 ( 8 )   1735 - 1741   2004

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    DOI: 10.1039/b400128a

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  • Two-color two-laser DNA damaging Reviewed

    K Kawai, Cai, X, A Sugimoto, S Tojo, M Fujitsitka, T Majima

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   43 ( 18 )   2406 - 2409   2004

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    DOI: 10.1002/anie.200353318

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  • Hole transfer in DNA by monitoring the transient absorption of radical cations of organic molecules conjugated to DNA Reviewed

    K Kawai, T Majima

    LONG-RANGE CHARGE TRANSFER IN DNA I   236   117 - 137   2004

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  • Transient phenomena of polyphenyls in the higher triplet excited state Reviewed

    X. Cai, M. Sakamoto, M. Hara, S. Tojo, K. Kawai, M. Endo, M. Fujitsuka, T. Majima

    Journal of Physical Chemistry A   108 ( 43 )   9361 - 9364   2004

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    DOI: 10.1021/jp047184e

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  • Effects of benzyl ether type dendrons as hole-harvesting antennas, and shielding for the neutralization of stilbene core radical cations with chloride ion during two-photon ionization of stilbene dendrimers having stilbene core and benzyl ether type dendr Reviewed International journal

    M. Hara, S. Samori, X. Cai, S. Tojo, T. Arai, A. Momotake, J. Hayakawa, M. Uda, K. Kawai, M. Endo, M. Fujitsuka, T. Majima

    Journal of the American Chemical Society   126 ( 43 )   14217 - 14223   2004

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    The two-photon ionization (TPI) process (308 and 266 nm) of stilbene dendrimers having a stilbene core and benzyl ether type dendrons has been investigated in an acetonitrile and 1,2-dichloroethane mixture (3:1) in order to elucidate the dendrimer effects. The quantum yield of the formation of stilbene core radical cation during the 308-nm TPI was independent of the dendron generation of the dendrimers, whereas a generation dependence of the quantum yield of the radical cation was observed during the 266-nm TPI, where both the stilbene core and benzyl ether type dendron were ionized, suggesting that the subsequent hole transfer occurs from the dendron to the stilbene core, and that the dendron acts as a hole-harvesting antenna. The neutralization rate of the stilbene core radical cation with the chloride ion, generated from the dissociative electron capture by 1,2-dichloroethane, decreased with the increase in the dendrimer generation, suggesting that the dendron is an effective shield of the stilbene core radical cation against the chloride ion.

    DOI: 10.1021/ja046650a

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  • Stepwise photocleavage of two C-O bonds of ′1,8-Bis [(4,-benzoylphenoxy)-methyl]naphthalene with three-step excitation using three-color, three-laser flash photolysis Reviewed International journal

    X. Cai, M. Sakamoto, M. Hara, S. Tojo, A. Ouchi, K. Kawai, M. Endo, M. Fujitsuka, T. Majima

    Journal of the American Chemical Society   126 ( 24 )   7432 - 7433   2004

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    Stepwise photocleavage of two naphthylmethyl-oxygen bonds of 1,8-bis[(4-benzoylphenoxy)methyl]naphthalene (1,8-(BPO-CH2)2Np, 1) was observed during three-color, three-laser flash photolysis at room temperature. The mechanism from 1 to the final product, acenaphthene (2), was clearly elucidated. The first (308 nm, 5 mJ pulse-1) XeCl laser excited 1 to the lowest triplet excited state 1(T1), in which the excited energy was localized in the naphthalene moiety, but the C-O bond cleavage did not occur. The second (430 nm, 7 mJ pulse-1) OPO laser excited 1(T1) to the higher triplet excited states 1(Tn) in which the excited energy is delocalized in the naphthalene moiety and C-O bonds, and one C-O bond cleavage occurred. The third (355 nm, 10 mJ pulse-1) YAG laser excited the carbon-centered radical in the ground state 1-(BPO-CH2)NpCH2*(D0) to its excited states 1-(BPO-CH2)NpCH2*(Dn), from which the second C-O bond cleavage occurred to give 2 as the final product. This is a successful example of stepwise cleavage of two equivalent C-O bonds in a molecule using three-color three-laser photolysis method.

    DOI: 10.1021/ja049007x

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  • Rate constant of bimolecular triplet energy transfer from chrysene in the higher triplet excited states Reviewed

    X. Cai, M. Sakamoto, M. Hara, S. Tojo, K. Kawai, M. Endo, M. Fujitsuka, T. Majima

    Journal of Physical Chemistry A   108 ( 35 )   7147 - 7150   2004

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    DOI: 10.1021/jp0479771

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  • Excess electron transfer in DNA studied by pulse radiolysis and gamma-radiolysis of naphthalimide and lodouridine modified ODN Reviewed

    K Kawai, T Kimura, K Kawabata, S Tojo, T Majima

    JOURNAL OF PHYSICAL CHEMISTRY B   107 ( 46 )   12838 - 12841   2003.11

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    DOI: 10.1021/jp034621

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  • Benzophenones in the higher triplet excited states. International journal

    Xichen Cai, Masanori Sakamoto, Michihiro Hara, Akira Sugimoto, Sachiko Tojo, Kiyohiko Kawai, Masayuki Endo, Mamoru Fujitsuka, Tetsuro Majima

    Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology   2 ( 11 )   1209 - 14   2003.11

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    Transient phenomena of benzophenone (BP) in the higher triplet excited state (Tn) have been investigated by the two-colour two-laser excitation method. Triplet energy transfer from BP(Tn) to quenchers (Q) occurred within the duration of a laser pulse (5 ns) to give Q(T1) with higher triplet energy than that of BP(T1). The quantum yield of the triplet energy-transfer quenching of BP(Tn) by CCl4 was found to be 0.0023 +/- 0.0002 from the bleaching of the transient absorption of BP(T1) and the absorbed photon number. It appears that internal conversion from BP(Tn) to BP(T1) is the predominant process. The lifetimes (tauTn) of BP(Tn) and several substituted benzophenones (BPs) in the higher triplet excited state [BPs(Tn)] were estimated from the dependence of the Q concentration on the efficiency of the triplet energy-transfer quenching of BP(Tn) by Q, and found to be 110-450 ps, depending on the nature of the substituents on the BPs. The effect of the substituents on tauTn may be explained by the energy gap between the Tn and T1 states, because the main deactivation pathway for BPs(Tn) is the internal conversion process. In contrast, the substituent effect on the lifetimes of BPs(T1) cannot be explained by the energy gap law. The transient behaviour of Q(T1) depends on the properties of the quencher. Sequential triplet energy transfer from Q(T1) to BP occurred for p-dichlorobenzene and tert-butylbenzene as quenchers, while Q(T1) reacted partly with Q to form triplet excimers (3Q2*) for benzene, chlorobenzene, and o-dichlorobenzene as quenchers. When CCl4 was used as the quencher, the homolytic cleavage of a C-Cl bond of CCl4(T1) occurred to give Cl* and Cl3C* radicals.

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  • Hole transfer in pyrene-conjugated DNA Reviewed

    K Kawai, T Majima

    JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN   61 ( 6 )   614 - 619   2003.6

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    DOI: 10.5059/yukigoseikyokaishi.61.614

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  • Photo-regulation of hole transfer in DNA studied by pulse radiolysis-laser flash photolysis combined method Reviewed

    T Takada, K Kawai, S Tojo, T Majima

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   225   U390 - U390   2003.3

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  • Naphthalene in the higher triplet excited state. Reviewed International journal

    Cai X, Hara M, Kawai K, Tojo S, Majima T

    Chemical communications (Cambridge, England)   ( 2 )   222 - 223   2003.1

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    Naphthalene in the higher triplet excited state Np(Tn) was generated from the two-step excitation method using two-colour two-laser flash photolysis technique and the lifetime of Np(Tn) was estimated to be 4.5 ps from the triplet energy quenching by quenchers such as p-dichlorobenzene, o-dicyanobenzene and carbon tetrachloride.

    DOI: 10.1039/b210118a

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  • Regulation of one-electron oxidation rate of guanine and hole transfer rate in DNA through hydrogen bonding Reviewed

    K Kawai, T Takada, S Tojo, T Majima

    TETRAHEDRON LETTERS   43 ( 45 )   8083 - 8085   2002.11

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  • Regulation of one-electron oxidation rate of guanine by base pairing with cytosine derivatives. Reviewed International journal

    Kawai K, Wata Y, Hara M, Tojo S, Majima T

    Journal of the American Chemical Society   124 ( 14 )   3586 - 3590   2002.4

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    Effects of base pairing on the one-electron oxidation rate of guanine derivatives, guanine, 8-bromoguanine, and 8-oxo-7,8-dihydroguanine have been studied. The one-electron oxidation rate of guanine derivatives was determined by triplet-quenching experiments, using N,N'-dibutylnaphthaldiimide (NDI) in the triplet excited state (3NDI*) and fullerene (C(60)) in the triplet excited state ((3)C(60*)) as oxidants. In all three guanine derivatives studied here, acceleration of the one-electron oxidation was observed upon hydrogen bonding with cytosine, which demonstrates lowering of the oxidation potential of guanine derivatives by base pairing with cytosine. When a methyl or bromo group was introduced to the C5 position of cytosine, acceleration or suppression of the one-electron oxidation relative to the guanine:cytosine base pair was observed, respectively. The results demonstrate that the one-electron oxidation rate of guanine in DNA can be regulated by introducing a substituent on base pairing cytosine.

    DOI: 10.1021/ja016530s

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  • Hole transfer through DNA monitored by transient absorption of phenothiazine radical cation (vol 43, pg 89, 2002) Reviewed

    K Kawai, T Takada, S Tojo, T Majima

    TETRAHEDRON LETTERS   43 ( 12 )   2321 - 2321   2002.3

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  • Hole transfer through DNA monitored by transient absorption of phenothiazine radical cation Reviewed

    K Kawai, T Takada, S Tojo, T Majima

    TETRAHEDRON LETTERS   43 ( 1 )   89 - 91   2002.1

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  • Selective enhancement of the one-electron oxidation of guanine by base pairing with cytosine Reviewed

    K Kawai, Y Wata, N Ichinose, T Majima

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   39 ( 23 )   4327 - +   2000

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    DOI: 10.1002/1521-3773(20001201)39:23<4327::AID-ANIE4327>3.0.CO;2-6

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  • 8-Methylguanine-containing oligonucleotides: useful structural constraint for Z form DNA. Reviewed

    Kawai K, Sugiyama H, Fujimoto K, Saito I

    Nucleic acids symposium series   ( 34 )   33 - 34   1995

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  • Hidden Markov simulation for material science dynamic data: Analysis for fluorescence blinking data of DNA

    古田達央, 中村和磨, 近藤洋平, 丸山厚, 川井清彦, 高田忠雄, 藤塚守

    日本物理学会講演概要集(CD-ROM)   79 ( 1 )   2024

  • 蛍光blinking制御による生体分子ダイナミクスの1分子計測

    川井清彦, 藤塚守, 丸山厚, 近藤洋平

    日本分子生物学会年会プログラム・要旨集(Web)   47th   2024

  • Kinetics of Photoinduced Reactions at the Single-Molecule Level: The KACB Method

    Kiyohiko Kawai, Atsushi Maruyama

    Chemistry - A European Journal   26 ( 35 )   7740 - 7746   2020.6

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    Language:English   Publishing type:Rapid communication, short report, research note, etc. (scientific journal)   Publisher:Wiley-VCH Verlag  

    DOI: 10.1002/chem.202000439

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  • 蛍光blinking制御による核酸構造転移の1分子観測

    川井清彦, 宮田貴史, 嶋田直彦, 伊都将司, 宮坂博, 丸山厚

    光化学討論会要旨集(CD-ROM)   2018   2018

  • Long-Range Charge Transfer through DNA by Replacing Adenine with Diaminopurine

    Kiyohiko Kawai, Haruka Kodera, Tetsuro Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   132 ( 2 )   627 - 630   2010.1

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  • Sequence-independent and rapid long-range charge transfer through DNA

    Nature Chem.   1 2 156-159   2009

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  • Kinetic Studies of Long-Range Hole Transfer through DNA

    2009

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  • Kinetics of charge transfer in DNA containing a mismatch

    Yasuko Osakada, Kiyohiko Kawai, Mamoru Fujitsuka, Tetsuro Majima

    NUCLEIC ACIDS RESEARCH   36 ( 17 )   5562 - 5570   2008.10

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  • Mechanism of charge separation in DNA by hole transfer through consecutive adenines

    Kiyohiko Kawai, Yasuko Osakada, Mamoru Fujitsuka, Tetsuro Majima

    Chemistry - A European Journal   14 ( 12 )   3721 - 3726   2008.4

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  • Charge separation in acridine- and phenothiazine-modified DNA

    Kiyohiko Kawai, Yasuko Osakada, Mamoru Fujitsuka, Tetsuro Majima

    Journal of Physical Chemistry B   112 ( 7 )   2144 - 2149   2008.2

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    DOI: 10.1021/jp075326+

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  • Charge Transfer in DNA

    2008

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  • Charge Separation in Acridine- and Phenothiazine-Modified DNA

    J. Phys. Chem. B   112 7 2144-2149   2008

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  • Photocatalytic Cleavage of Single TiO2/DNA Nanoconjugates

    Chem. Eur. J.   14 5 1492-1498   2008

  • Mechanism of Charge-Separation in DNA via Hole Transfer through Consecutive Adenines

    Chem. Eur. J.   14 12 3721-13726   2008

  • Hole Transfer in DNA and Photosensitized DNA Damage: Importance of Adenine Oxidation

    2008

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  • Kinetic SNP typing Based on Charge Transfer through DNA

    2008

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  • Charge Separation in Acridine Modified DNA

    2008

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  • Charge transfer in DNA assembly: effects of sticky end

    Chem. Commun.   2656-2658   2008

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  • Monitoring G-quadruplex structures and G-quadruplex-ligand complex using 2-aminopurine modified oligonucleotides

    Takumi Kimura, Kiyohiko Kawai, Mamoru Fujitsuka, Tetsuro Majima

    TETRAHEDRON   63 ( 17 )   3585 - 3590   2007.4

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  • Hole transfer in DNA and photosensitized DNA damage: Importance of adenine oxidation

    Kiyohiko Kawai, Yasuko Osakada, Mamoru Fujitsuka, Tetsuro Majima

    JOURNAL OF PHYSICAL CHEMISTRY B   111 ( 9 )   2322 - 2326   2007.3

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  • Spin-correlated radical pairs in synthetic hairpin DNA

    Satoru Nakajima, Kimio Akiyama, Kiyohiko Kawai, Tadao Takada, Tadaaki Ikoma, Tetsuro Majima, Shozo Tero-Kubota

    CHEMPHYSCHEM   8 ( 4 )   507 - 509   2007.3

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  • Charge Separation via Rapid Hole Transfer through Adenine-Hopping

    2007

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  • Hole transfer rates in A-form DNA/2′-OMeRNA hybrid

    Kiyohiko Kawai, Yasuko Osakada, Akira Sugimoto, Mamoru Fujitsuka, Tetsuro Majima

    Chemistry - A European Journal   13 ( 8 )   2386 - 2391   2007

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  • Hole transfer rates in A-from DNA/2'-OMeRNA hybrid

    Chem. Eur. J.   13 8 2386-2391   2007

  • Monitoring G-Quadruplex Structures and G-Quadruplex-ligand Complex by 2-Aminopurine Modified Oligonucleotide

    Tetrahedron   63 17 3585-3590   2007

  • Hole Transfer in DNA and Photosensitized DNA Damage: Importance of Adenine Oxidation

    J. Phys. Chem. B   111 9 2322-2326   2007

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  • Spin-correlated radical pairs in the synthetic hairpin DNA

    ChemPhysChem   8 4 507-509   2007

  • Monitoring of microenvironmental changes in the major and minor grooves of DNA by dan-modified oligonucleotides

    Kimura Takumi, Kawai Kiyohiko, Majima Tetsuro

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   231   2006.3

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  • Formation of pyrene dimer radical cation at the minor groove of DNA

    K Kawai, T Kimura, H Yoshida, A Sugimoto, S Tojo, M Fujitsuka, T Majima

    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN   79 ( 2 )   312 - 316   2006.2

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  • Detection of the G-quadruplex-TMPyP4 complex by 2-aminopurine modified human telomeric DNA

    T Kimura, K Kawai, M Fujitsuka, T Majima

    CHEMICAL COMMUNICATIONS   No. 4, pp. 401-402 (2006) ( 4 )   401 - 402   2006.1

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  • High-yield generation of a long-lived charge-separated state in diphenylacetylene-modified DNA

    T Takada, K Kawai, M Fujitsuka, T Majima

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   45 ( 1 )   120 - 122   2006

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  • Monitoring of microenvironmental changes in the major and minor grooves of DNA by dan-modified oligonucleotides

    T Kimura, K Kawai, T Majima

    ORGANIC LETTERS   7 ( 26 )   5829 - 5832   2005.12

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  • Synthesis and properties of terthiophene-modified oligodeoxynucleotides

    K Kawai, A Sugimoto, H Yoshida, S Tojo, M Fujitsuka, T Majima

    BIOORGANIC & MEDICINAL CHEMISTRY LETTERS   15 ( 20 )   4547 - 4549   2005.10

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  • Consecutive adenine sequences are potential targets in photosensitized DNA damage

    K Kawai, Y Osakada, M Fujitsuka, T Majima

    CHEMISTRY & BIOLOGY   12 ( 9 )   1049 - 1054   2005.9

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  • Kinetics of transient end-to-end contact of single-stranded DNAs

    K Kawai, H Yoshida, A Sugimoto, M Fujitsuka, T Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   127 ( 38 )   13232 - 13237   2005.9

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  • Selective guanine oxidation by UVB-irradiation in telomeric DNA

    K Kawai, M Fujitsuka, T Majima

    CHEMICAL COMMUNICATIONS   No. 11, pp. 1476-1477 (2005)/, ( 11 )   1476 - 1477   2005

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  • Photocatalytic oxidation reactivity of holes in the sulfur- and carbon-doped TiO2 powders studied by time-resolved diffuse reflectance spectroscopy

    T Tachikawa, S Tojo, K Kawai, M Endo, M Fujitsuka, T Ohno, K Nishijima, Z Miyamoto, T Majima

    JOURNAL OF PHYSICAL CHEMISTRY B   108 ( 50 )   19299 - 19306   2004.12

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  • Lifetime regulation of the charge-separated state in DNA by modulating the oxidation potential of guanine in DNA through hydrogen bonding

    K Kawai, Y Osakada, T Takada, M Fujitsuka, T Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   126 ( 40 )   12843 - 12846   2004.10

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  • Formation of pyrene dimer radical cation at the internal site of oligodeoxynucleotides

    K Kawai, H Yoshida, T Takada, S Tojo, T Majima

    JOURNAL OF PHYSICAL CHEMISTRY B   108 ( 35 )   13547 - 13550   2004.9

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  • Direct observation of hole transfer through double-helical DNA over 100 A

    T Takada, K Kawai, M Fujitsuka, T Majima

    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA   101 ( 39 )   14002 - 14006   2004.9

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  • Formation and Decay of Pyrene Radical Cation and Pyrene Dimer Radical Cation in the Absence and Presence of Cyclodextrins during Resonant Two-Photon Ionization of Pyrene and Sodium 1-Pyrene Sulfonate Reviewed

    Michihiro Hara, Sachiko Tojo, Kiyohiko Kawai, Tetsuro Majima

    Physical Chemistry Chemical Physics   6 ( 13 )   3215 - 3220   2004.6

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  • Fluorescence properties of 2-aminopurine in human telomeric DNA

    T Kimura, K Kawai, M Fujitsuka, T Majima

    CHEMICAL COMMUNICATIONS   No. 12, pp. 1438 - 1439/, ( 12 )   1438 - 1439   2004.6

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  • Charge separation in DNA via consecutive adenine hopping

    T Takada, K Kawai, XC Cai, A Sugimoto, M Fujitsuka, T Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   126 ( 4 )   1125 - 1129   2004.2

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  • Fluorescence properties of 2-aminopurine-cytidine-7-deazaguanine (5 '-ApC(dz)G-3 ') trimer in B- and Z-DNA

    T Kimura, K Kawai, T Majima

    CHEMICAL COMMUNICATIONS   ( 3 )   268 - 269   2004.2

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  • One-electron attachment reaction of B- and Z-DNA modified by 8-bromo-2 '-deoxyguanosine

    T Kimura, K Kawai, S Tojo, T Majima

    JOURNAL OF ORGANIC CHEMISTRY   69 ( 4 )   1169 - 1173   2004.2

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  • Effects of interaction of photosensitizer with DNA and stacked G bases on photosensitized one-electron oxidation of DNA

    T Takada, K Kawai, S Tojo, T Majima

    JOURNAL OF PHYSICAL CHEMISTRY B   108 ( 2 )   761 - 766   2004.1

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  • Hole transfer in DNA by monitoring the transient absorption of radical cations of organic molecules conjugated to DNA

    K Kawai, T Majima

    LONG-RANGE CHARGE TRANSFER IN DNA I   236   117 - 137   2004

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    DOI: 10.1007/b94413

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  • Kinetics of multistep hole transfer in DNA by monitoring the transient absorption of the pyrene radical cation

    T Takada, K Kawai, S Tojo, T Majima

    JOURNAL OF PHYSICAL CHEMISTRY B   107 ( 50 )   14052 - 14057   2003.12

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  • Long-lived charge-separated state leading to DNA damage through hole transfer

    K Kawai, T Takada, T Nagai, XC Cai, A Sugimoto, M Fujitsuka, T Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   125 ( 52 )   16198 - 16199   2003.12

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  • Some triplet energy-transfer re actions initiated by photo-excitation of triplet excited state of dibenz[a h]anthracene to the higher triplet excited states Reviewed

    Xichen Cai Michihiro Hara, Kiyohiko Kawai, Sachiko Tojo, Mamoru Fujitsuka, Tetsuro Majima

    Tetrahedron Letters   44 ( 32 )   6117 - 6120   2003.8

  • Kinetics of weak distance-dependent hole transfer in DNA by adenine-hopping mechanism

    K Kawai, T Takada, S Tojo, T Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   125 ( 23 )   6842 - 6843   2003.6

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  • Hole transfer in DNA: DNA as a scaffold for hole transfer between two organic molecules

    T Takada, K Kawai, S Tojo, T Majima

    TETRAHEDRON LETTERS   44 ( 19 )   3851 - 3854   2003.5

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  • Sensitized reactions by Benzophenone in the Higher Triplet Excited State Reviewed

    Xichen Cai Michihiro Hara, Kiyohiko Kawai, Sachiko Tojo, Tetsuro Majima

    Chemical Physics Letters   371 ( 1-2 )   68 - 73   2003.3

  • Efficient C2 'alpha-hydroxylation of deoxyribose in protein-induced Z-form DNA

    T Oyoshi, K Kawai, H Sugiyama

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   125 ( 6 )   1526 - 1531   2003.2

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  • Formation of pyrene dimer radical cation in DNA reflecting DNA dynamics in the time range of 1 mu s to 1 ms

    K Kawai, K Miyamoto, S Tojo, T Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   125 ( 4 )   912 - 915   2003.1

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  • Properties of chrysene in the higher triplet excited state Reviewed

    Xichen Cai Michihiro Hara, Kiyohiko Kawai, Sachiko Tojo, Tetsuro Majima

    Chemical Physics Letters   368 ( 3-4 )   365 - 369   2003.1

  • Excess Electron Transfer in DNA Studied by Pulse Radiolysis and γ-Radiolysis of Naphthalimide and Iodouridine Containing ODN

    KAWAI K, KIMURA T, KAWABATA K, TOJO S, MAJIMA T

    J. Phys. Chem. B 107/46, 12838-12841 (2003).   107 ( 46 )   12838 - 12841   2003

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  • Effects of base pairing on the one-electron reduction rate of cytosine

    K Kawai, A Yokoohji, S Tojo, T Majima

    CHEMICAL COMMUNICATIONS   2840-2841 ( 22 )   2840 - 2841   2003

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  • Synthesis of ODNs containing 4-methylamino-1,8-naphthalimide as a fluorescence probe in DNA

    K Kawai, K Kawabata, S Tojo, T Majima

    BIOORGANIC & MEDICINAL CHEMISTRY LETTERS   12 ( 17 )   2363 - 2366   2002.9

  • Pulse Radiolytic Study of Hole Transfer in DNA

    KAWAI Kiyohiko, MAJIMA Tetsuro

    73   28 - 31   2002.3

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  • Effect of hydrogen bonding on the photo-oxidation of DNA

    Kiyohiko Kawai, Tetsuro Majima

    Journal of Photochemistry and Photobiology C: Photochemistry Reviews   3 ( 1 )   53 - 66   2002

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    DOI: 10.1016/S1389-5567(02)00005-9

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  • Observation of hole transfer through DNA by monitoring the transient absorption of pyrene radical cation

    K Kawai, T Takada, S Tojo, N Ichinose, T Majima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   123 ( 50 )   12688 - 12689   2001.12

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  • Enhancement of One-Electron Oxidation of Guanine by Base-Pairing with Cytosine

    Proceedings of the 4th SANKEN International Symposium on Biological Molecular Machines and Bio-devices, pp.~77-78   pp.~77-78   2001

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  • Hydrogen Bonding Modulation of Electron Transfer Rate of DNA

    Proceedings of the 4th International Symposium on InterMaterial, p.~79   p.~79   2001

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  • Hole Transfer in DNA

    Proceedings of the 4th SANKEN International Symposium on Biological Molecular Machines and Bio-devices, pp.~79-80   pp.~79-80   2001

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  • Selective enhancement of the one-electron oxidation of guanine by base pairing with cytosine

    Kiyohiko Kawai, Yasuharu Wata, Nobuyuki Ichinose, Tetsuro Majima

    Angewandte Chemie - International Edition   39 ( 23 )   4327 - 4329   2000.12

  • Selective Enhancement of One-Electron Oxidation of Guanine by Base-Pairing with Cytosine

    Angew.~Chem.~Int.~Ed.~Eng., Vol.~39, No.~23, pp.~4327-4329   Vol.~39, No.~23, pp.~4327-4329   2000

  • Effect of Base-Pairing on One-Electron Oxidation of Guanine

    Proceedings of the 3rd SANKEN International Symposium on Advanced Nanoelectronics: Materials, Devices and Computing, pp.~189-190   pp.~189-190   2000

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  • One-electron Oxidation of DNA

    Abstracts of the 8th Japan-China Bilateral Symposium on Photochemistry, pp.~121-122   pp.~121-122   2000

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  • Enhancement of One-Electron Oxidation of Guanine by Base-Pairing with Cytosine

    Abstracts of the 2000 International Chemical Congress of Pacific Basin Societies (PACIFICHEM 2000), p.~ORGN 9, Paper 144   9, Paper 144   2000

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  • Pulse Radiolytic Study of Charge Transport through DNA

    Abstracts of the satellite symposium of the International Symposium on Prospect for Application of Radiation towards the 21st Century, p.~46   p.~46   2000

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  • Charge Transfer in DNA

    Abstracts of COE: Third International Symposium on Atomic Scale Processing and Novel Properties in Nanoscopic Materials, p.~20   p.~20   2000

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  • Enhancement of One-Electron Oxidation of Guanine by Base-Pairing with Cytosine

    Abstracts of the 2000 International Chemical Congress of Pacific Basin Societies (PACIFICHEM 2000), p.~ORGN 9, Paper 144   9, Paper 144/,   2000

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  • Controlling the Electron Transfer Rate by the Hydrogen-Bond of DNA Monomer

    Abstracts of COE: Third International Symposium on Atomic Scale Processing and Novel Properties in Nanoscopic Materials, p.~109   p.~109   2000

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  • Charge Transfer in DNA

    Abstracts of COE: Third International Symposium on Atomic Scale Processing and Novel Properties in Nanoscopic Materials, p.~108   p.~108   2000

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  • 分子スケールの光論理ゲートの集積

    川井 清彦, 真嶋 哲朗

    光化学 = Photochemistry   30 ( 2 )   142 - 143   1999.8

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  • Photochemical halogen-exchange reaction of 5-iodouracil-containing oligonucleotides

    K Kawai, Saito, I, H Sugiyama

    TETRAHEDRON LETTERS   40 ( 31 )   5721 - 5724   1999.7

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  • Intrastrand 2'β hydrogen abstraction of 5'-adjacent deoxyguanosine by deoxyuridin-5-yl in Z-form DNA

    Kiyohiko Kawai, Isao Saito, Etsuko Kawashima, Yoshiharu Ishido, Hiroshi Sugiyama

    Tetrahedron Letters   40 ( 13 )   2589 - 2592   1999.3

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  • Conformation-dependent photochemistry of 5-halouracil-containing DNA: Stereospecific 2 'alpha-hydroxylation of deoxyribose in Z-form DNA

    K Kawai, Saito, I, H Sugiyama

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   121 ( 6 )   1391 - 1392   1999.2

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  • Conformation Dependent Photochemistry of 5-Halouracil Containing DNA : Stereo-Specific 2'α-Hydroxylation of Deoxyribose in Z-form DNA.

    J. Am. Chem. Soc.   121 ( 6 )   1391 - 1392   1999

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  • Construction of Molecular-scale Photologic Gates

    Vol.~30, No.~2, pp.~142-143   1999

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  • Construction of Molecular-scale Photologic Gates

    Vol.~30, No.~2, pp.~142-143/,   1999

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  • Conformation Dependent Photochemistry of 5-Halouracil Containing DNA: Stereospecific 2'a-Hydroxylation of Deoxyribose in Z-form DNA

    121, 1391-1392   1999

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  • Stabilization of Hoogsteen base pairing by introduction of NH2 group at the C8 position of adenine

    K Kawai, Saito, I, H Sugiyama

    TETRAHEDRON LETTERS   39 ( 29 )   5221 - 5224   1998.7

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  • Conformation Dependent Photochemistry of 5-Halouracil Containing DNA : Specific ribose 2'-hydroxylation in Z-form DNA.

    Nucleic Acids Symp. Ser.   39   99 - 100   1998

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  • Photoreaction of 5-halouracil-containing Z-form DNA.

    K Kawai, H Sugiyama, Saito, I

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   214   103 - ORGN   1997.9

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  • Photoreaction of 5-Halouracil-Containing Z-form DNA.

    Photomedicine and Photobiology   19   95 - 97   1997

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  • Photoreaction of 5-halouracil-containing Z-form DNA.

    Nucleic Acids Symp. Ser.   37   93 - 94   1997

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  • Synthesis, structure and thermodynamic properties of 8-methylguanine-containing oligonucleotides: Z-DNA under physiological salt conditions

    H Sugiyama, K Kawai, A Matsunaga, K Fujimoto, Saito, I, H Robinson, AHJ Wang

    NUCLEIC ACIDS RESEARCH   24 ( 7 )   1272 - 1278   1996.4

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  • Effects of methylation on B-to Z-DNA transition.

    Nucleic Acids Symp. Ser   35   87 - 88   1996

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  • Photoreactivity of BrU-Conaining Oligonucleotides in Z-form.

    川井清彦, 藤本健造, 杉山弘, 斎藤烈

    日本化学会講演予稿集   70th ( 2 )   1996

  • Regulation of B-Z Transition by Introduction of 8-Methyldeoxyguanosine.

    川井清彦, 藤本健造, 松永篤, 杉山弘, 斎藤烈

    日本化学会講演予稿集   69th ( 2 )   1995

  • Synthesis of Oligonucleotides Containing 8-Methyldeoxyguanosine and Their Photoreactivity.

    杉山弘, 藤本健造, 松永篤, 川井清彦, 斎藤烈

    日本化学会講演予稿集   67th ( 2 )   1994

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Awards

  • The Japanese Photochemistry Association Award

    2021.9   The Japanese Photochemistry Association   Single-molecule photochemistry of nucleic acids and its application to single-molecule analysis and diagnosis

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  • 大阪大学総長奨励賞

    2015.7   大阪大学  

    川井 清彦

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  • 大阪大学総長奨励賞

    2014.7   大阪大学  

    川井 清彦

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  • BCSJ賞

    2013.1   日本化学会  

    川井 清彦

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  • ISNAC Outstanding Oral Presentation Award in 2011

    2011.11   International Symposium on Nucleic Acids Chemistry (ISNAC)  

    KAWAI Kiyohiko

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  • The Japanese Photochemistry Association Prize for Young Scientist for 2008

    2008  

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  • 第86回春季年会優秀講演賞

    2006.3   日本化学会  

    川井 清彦

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  • 日本光医学・光生物学会 奨励賞

    2001  

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    Country:Japan

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Research Projects

  • 蛍光ブリンキング制御による細胞内粘度・拡散速度の超解像計測

    Grant number:24K01624  2024.4 - 2027.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    川井 清彦, 丸山 厚, 田邉 一仁

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    Grant amount:\18590000 ( Direct Cost: \14300000 、 Indirect Cost:\4290000 )

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  • Integrated understanding and manipulation of hypoxic cellular functions by artificial nucleic acids with hypoxia-accumulating properties

    Grant number:23K26779  2023.4 - 2026.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

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    Grant amount:\19110000 ( Direct Cost: \14700000 、 Indirect Cost:\4410000 )

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  • RNAダイナミクスの学理構築とRNA標的薬剤アッセイ系の構築

    Grant number:21H02059  2021.4 - 2024.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    川井 清彦, 田邉 一仁

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    Grant amount:\17420000 ( Direct Cost: \13400000 、 Indirect Cost:\4020000 )

    2021年度は、RNA構造転移の測定法の1つとして、三重項-三重項エネルギー移動を利用した、RNA構造転移の測定法の開発に取り組んだ。一重項-一重項エネルギー移動であるFRETでは、一般にエネルギードナー、アクセプター間の距離が50Å程度以上変化する大きな構造転移の観測に優れている。これに対し、三重項-三重項エネルギー移動では、ドナー、アクセプター間の衝突が必要であるため、ドナー、アクセプターが衝突するRNAの分子運動に絞って追跡できる。ここで、1分子蛍光観察特有の現象であるblinkingを利用し、蛍光相関解析から三重項-三重項エネルギー移動が起こるのに要する時間(τT)を求める(1/τT はRNA分子運動速度に対応)。アクセプターとしては1,4,5,8-cyclooctatetraene(COT)を用いる。COTは、三重項-三重項エネルギー移動によりエネルギーを受け取り、100 μs以内にそのエネルギーを熱として放出し、蛍光分子の光安定性を向上させることが報告されている。蛍光分子としてATTO 647N、市販のCOTアミダイト誘導体を用いて、DNAをプラットフォームとしてblinkingにより三重項-三重項エネルギー移動の観測を試みたところ、τTがATTO 647NとCOT間の1本鎖DNAスペーサが長くなるほど長くなった。また、DNAスペーサがより柔軟なポリTの時に、より剛直なポリAと比べτTが長くなり、τTがDNAの1本鎖ダイナミクスにより起こるATTO 647NとCOTの分子衝突に要する時間を反映している、すなわち、τTの測定により核酸の構造転移を観測できることが示された。

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  • Elucidation of the mechanism of mutagenesis by transient nucleobase adducts

    Grant number:19K22256  2019.6 - 2022.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Research (Exploratory)

    KAWAI KIYOHIKO

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    Grant amount:\6370000 ( Direct Cost: \4900000 、 Indirect Cost:\1470000 )

    In this study, we aimed to gain insight into the formation of N2-ethylidene-G (ethG), a nucleic acid adduct transiently induced in the body by the ingestion of alcohol, a carcinogen. Using PacBio's RSII+ next-generation sequencer, we have successfully observed the formation of ethG in the presence of relatively high concentrations of acetaldehyde on the order of mM by tracking single molecules of the binding and dissociation processes of nucleic acids. The results of this study highlight the need for appropriate processing of large amounts of data in order to discuss the formation of ethG in detail and quantitatively. In order to establish a data analysis method for the formation and dissociation process of transiently formed ethG, single molecule analysis of nucleic acid aptamers was achieved.

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  • DNA高次構造転移の1分子実時間観測

    2017.4 - 2020.3

    日本学術振興会  科研費 基盤研究(B) 

    川井 清彦

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  • RNA1分子検出による癌の遺伝子点突然変異診断

    2017.4 - 2019.3

    キヤノン財団  研究助成プログラム「産業基盤の創生」 

    川井 清彦

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    Authorship:Principal investigator  Grant type:Competitive

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  • 弱い過渡的相互作用をトリガーとしたRNAの1分子イメージング

    2016.4 - 2018.3

    日本学術振興会  科研費 新学術領域(共鳴誘導で革新するバイオイメージング) 

    川井 清彦

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  • DNA超らせんダイナミクスの1分子レベル解析

    2014.4 - 2016.3

    日本学術振興会  科研費 挑戦的萌芽研究 

    川井 清彦

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    Authorship:Principal investigator  Grant type:Competitive

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  • 蛍光のblinkingを自在に操る分子技術の創出

    2013.10 - 2017.3

    独立行政法人科学技術振興機構  さきがけ「分子技術と新機能創出」領域 

    川井 清彦

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  • RNAの編集、化学修飾情報の1分子レベル解析技術の開発

    2012.4 - 2015.3

    日本学術振興会  科研費 基盤研究(B) 

    川井 清彦

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  • らせんねじれ角およびHOMOギャップ改変によるDNA分子ワイヤーの構築

    Grant number:23108711  2011.4 - 2013.3

    日本学術振興会  科学研究費助成事業  新学術領域研究(研究領域提案型)

    川井 清彦

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    Grant amount:\4680000 ( Direct Cost: \3600000 、 Indirect Cost:\1080000 )

    種々のHOMOレベルを有する、天然および修飾核酸塩基を用いて、同一鎖上の核酸塩基間のHOMOレベルギャップがDNA内ホール移動速度に与える影響を調べた。GからGのホール移動において、介在するブリッジ塩基のHOMOレベルを様々に変化しホール移動速度を測定した。ホール移動速度は、HOMOギャップの減少に伴い高速化することがわかった。また、HOMOレベルギャップを調節することにより、DNA内ホール移動速度を3桁にわたり制御可能であることが示された。このように、核酸塩基間のHOMOギャップ縮小によりDNA内ホール移動の高速化が可能であることが明らかになった。
    核酸塩基のπ平面の重なりが大きいほどホール移動速度が速くなることが示唆されていた。DNAはらせんを形成する際、塩基対ごとに約35度のねじれを生じ、結果として塩基間のπスタッキング面積の減少をまねいている。修飾核酸の一つであるLocked Nucleic Acid(LNA)は、糖部位のコンフォメーションが3'-endoに固定された構造をとり、結果としてらせん角が通常のB型DNAの約35度から約26度へと減少し、πスタッキング面積が増加する。一方、LNA修飾によりDNAの構造がより剛直化することが報告されていた。DNA内ホール移動速度はLNA修飾により低下し、11塩基対をLNA置換するとホール移動速度が100倍以上減少することがわかった。次にG-C塩基対の水素結合数を減らし、核酸をより柔軟にする5-Me-2'-deoxyzebularine(B)がDNA中のホール移動速度に与える影響を調べた。シトシンをBに置換すると、ホール移動速度が20倍以上増加することがわかった。以上の結果から、DNA内をホールが移動するためにはDNAの分子運動が必須であり、DNAの柔軟化によってホール移動を高速化可能であることが示された。

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  • Monitoring the function of molecular beacon type probe at the single molecule level

    Grant number:23655155  2011 - 2012

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Exploratory Research

    KAWAI Kiyohiko

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    Grant amount:\4030000 ( Direct Cost: \3100000 、 Indirect Cost:\930000 )

    DNA site specifically modified with fluorescent molecule were synthesized. The lifetime of a fluorescent molecule in the triplet excited state was measured, which is reflected in the duration of the off time during the blinking of the fluorescence (tOFF). tOFF was determined by fluorescence correlation spectroscopy (FCS). It was demonstrated that the more a fluorescent molecule is exposed to a solvent, the faster its triplet excited state is quenched by molecular oxygen, resulting in a decrease of tOFF. DNA conformational change between a duplex and hairpin structure, function of the molecular beacon type probe, was successfully monitored by the blinking triggered by the changes in the solvent accessibility of the fluorescent molecule.

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  • Higher Excited State Chemistry Towards Molecular Device, Environmental Chemistry, and Nano- and Biotechnologies

    Grant number:22245022  2010 - 2012

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    MAJIMA Tetsuro, FUJITSUKA Mamoru, KAWAI Kiyohiko, TACHI KAWA Takashi

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    Grant amount:\48490000 ( Direct Cost: \37300000 、 Indirect Cost:\11190000 )

    The present research project aimed at application of higher excited state chemistry to molecular devices, environmental problem, and nano- and bio-technologies. Reaction processes through the higher excited states were investigated by various ultrafast spectroscopic methods and radiation chemical methods. The main achievements of this research project are clarification of ultrafast structural relaxation processes in the excited state, understandings of reaction processes from the excited radical ions, estimation of dynamics of excess electron in DNA, and so on.

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  • Reading out the DNA sequence information by measuring the lifetime of the charge separated state

    Grant number:21750170  2009 - 2010

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Young Scientists (B)

    KAWAI Kiyohiko

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    Grant amount:\4550000 ( Direct Cost: \3500000 、 Indirect Cost:\1050000 )

    Charge-separation and charge recombination in DNA was established using the fluorescent dyes those absorbs in the visible region. The lifetime of the charge-separated state was significantly affected by the surrounding sequences which enabled the read out the DNA sequence information based on the measurement of the lifetime of the charge separated state.

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  • DNAナノ光電荷分離システムの構築

    Grant number:18750148  2006 - 2007

    日本学術振興会  科学研究費助成事業  若手研究(B)

    川井 清彦

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    Grant amount:\3600000 ( Direct Cost: \3600000 )

    我々はこれまで、光増感剤としてナフタルイミドを用いることによりDNA内電荷分離状態の生成に成功してきた。しかしながら、光照射により強い酸化力を有するナフタルイミドを用いた場合、無差別にすべての塩基を酸化してしまうため近接塩基上にホールが発生し素早い逆電子移動が起こり電荷分離収率は数パーセント程度にとどまった。また、ナフタルイミドを用いる場合では紫外光照射が必要であり、太陽光エネルギー変換への応用が困難であった。本課題では、より太陽光を収集しやすい可視領域に強い吸収体を有し、酸化力が強すぎず、特定の核酸塩基のみを酸化可能なアクリジンなどを光増感剤(集光アンテナ)として用いることによる電荷分離システムの構築を目指した。長寿命の電荷分離状態を達成するためには、電子とホールを十分に引き離す必要がある。ここで、DNA2本鎖をホールの通り道として利用するが、逆電子移動を最小限にするため、市販されている種々の酸化電位を有する修飾核酸塩基を酸化電位の順に配列させ電荷が一方向に流れるよう検討を行った。設計、合成したDNAはすでに構築済みであるHPLCシステムを利用して精製し、UV融解温度測定(T_m測定)によりその構造の安定性を調べ、ナノ秒レーザーフォトリシスシステムを用いることによりその電荷分離の量子収率を評価した。その結果、可視光を用いたDNA内光電荷分離に成功し、また、電荷分離収率および電荷分離寿命をDNA配列により制御可能であることを明らかにした。

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  • Nanoscience of Photofuctionalized DNA

    Grant number:17105005  2005 - 2009

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (S)

    MAJIMA Tetsuro, FUJITSUKA Mamoru, KAWAI Kiyohiko, ENDO Masayuki

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    Grant amount:\107120000 ( Direct Cost: \82400000 、 Indirect Cost:\24720000 )

    Photoinduced charge separation and transfer mechanisms in DNA were clarified by using photofuctionalized DNA modified with various chromophores and high efficient and long-lifetime charge separation was established. Development of photoelectric energy conversion devices such as DNA molecular wire and light energy conversion units and highly effective DNA damage methods and creation of DNA photo-nanoscience was tried.

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  • DNA自己組織化に基づくカーボンナノチューブアレイの構築

    Grant number:17655085  2005 - 2006

    日本学術振興会  科学研究費助成事業  萌芽研究

    真嶋 哲朗, 川井 清彦

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    Grant amount:\3400000 ( Direct Cost: \3400000 )

    アレイ化したカーボンナノチューブを可視化することを目的とし、全反射蛍光顕微鏡を用いた単一分子蛍光顕微分光システムの構築を行った。具体的には、分光器および高感度CCDカメラを備え付けた全反射蛍光顕微鏡を開発した。本顕微分光システムの性能を評価するため、以下の研究を行った。二酸化チタン光触媒反応によって生成した一重項酸素などの酸素活性種を蛍光プローブにより単一分子レベルで検出することに成功した。二酸化チタン反応によって生成した一重項酸素は空気中へ飛散し、2mm以上離れた距離まで到達することを明らかにした。また、ペリレンナノ結晶の初期成長過程を水溶液中でその場観察することに成功し、種結晶形成機構に関する知見を得た。以上の結果から、本顕微分光システムが、単一ナノ材料の光誘起反応ならびに動的挙動の検出において強力な手法であることが明らかとなった。また、カーボンナノチューブと複合化させる自己組織化DNAにおける電荷移動機構を明らかにするため、レーザーフラッシュフォトリシス法による検討を行った。任意の塩基配列群をビルディングブロックとして用いることによりDNA中の電荷移動ダイナミクスを制御することに成功した。単層および多層カーボンナノチューブに蛍光色素を化学的に修飾し、カーボンナノチューブアレイの単一アレイ蛍光検出を行った。個々の蛍光色素修飾カーボンナノチューブアレイからの蛍光を検出することにより、集合体のサイズ、色素修飾率、光退色速度などを単一アレイレベルで評価した。

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  • 2波長2レーザー照射による高効率DNA切断

    Grant number:15750007  2003 - 2004

    日本学術振興会  科学研究費助成事業  若手研究(B)

    川井 清彦

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    Grant amount:\3600000 ( Direct Cost: \3600000 )

    皮膚ガン、胃ガンの治療法の一つとして、近年光線力学療法(PDT)が注目されている。高齢、心不全、他の病気の直後で外科療法が困難な患者に対して特に有効な治療法となりうる。PDTによる合併症等の報告例はほとんどないが、唯一日光過敏症が問題となつている。したがって、外用した光増感剤が代謝されるまでの数週間にわたり遮光が必要となる。そのため、出来る限り外用する増感剤の量を減らす事が望まれる。また、光源としては比較的高強度のパルスレーザーを必要とし、治療時間を要するため照射面積に制約をうけ、一定期間に治療しうる患者数も制限される。そこで、PDT普及のためにも少量の光増感剤を用いた高効率DNA切断法の開発が望まれる。本研究では、2波長2レーザー励起法を用いた高効率DNA切断法の開発を目指した。一般的に、DNA光増感一電子酸化反応の量子収率は極めて低い。それは主に、電子移動反応によりDNA中に生じたラジカルカチオンと増感剤ラジカルアニオンの間の電荷再結合に由来する。そこで、我々は二段階目に透過性の高い長波長のレーザーを用いてラジカルアニオンを励起し、電子を溶媒中に放出し、電荷再結合を妨げるととによる高効率DNA切断を検討した。昨年度、二段階目のレーザーを用いて、増感剤ラジカルアニオンから、溶媒へと電子放出が可能であるか検討した。その結果、溶媒へと電子を放出できること確認した。本年度は、実際に2波長2レーザー照射法がDNA損傷効率に与える影響について調べた。その結果、一段階目のレーザーのみ、二段階目のレーザーのみを用いた場合と比較し、2波長2レーザー照射により最大で10倍以上の損傷の増加が観測され、2波長2レーザー照射の原理をPDTへと応用可能であることが示された。

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  • Fundamental Science and Technology of Photofunctional Interfaces

    Grant number:14050055  2001 - 2006

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research on Priority Areas

    MAJIMA Tetsuro, TOJO Sachiko

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    Grant amount:\83800000 ( Direct Cost: \83800000 )

    The dynamic behaviors of radicals and radical ions generated on the surface of TiO_2 photocatalyst and the reactive intermediates from the reactions of the radicals and radical ions has been studied to elucidate 1) the reactive oxygen species and organic reactive intermediates generated during the TiO_2 photocatalytic reactions and 2) reactivities of organic radical ions generated during TiO_2 photocatalytic reactions, and to develop the method for the measurement of charge separation on the surface of the TiO_2 photocatalyst. There is an application to the environmental cleanup (contaminant processing) and medical technology as application of the TiO_2 photocatalyst reaction. An important finding was especially obtained in relation to it for the decomposition mechansm of the organic compounds in the TiO_2 photocatalyst reaction. In 2001-2005 fiscal years, we studied that adsorption and one-electron oxidation reaction process of the substrate adsorbed on the TiO_2 surface based on the time-resolved transient reflection measurement, and found that one-election oxidation efficiency depends on not only the oxidation potential of the substrate but also the electronic interaction between the substrate and surface of TiO_2 remarkably. In 2005-2007 fiscal years, we studied visible-light responsible TiO_2 photocatalyst, TiO_2 photocatalytic reaction in gas phase, one-electron redox processes during the polyoxometalate-mediated TiO_2 photocatalytic reactions, one-electron oxidation of organic molecule included in the cavity of β-cyclodextrin modified TiO_2 photocatalyst, and non-contact TiO_2 photocatalytic reaction based on the transient absorption measurement and single molecule fluorescence imaging technique. We found that the hydroxy radical and the singlet oxygen were generated from the surface of TiO_2 by the light irradiation of the TiO_2 photocatalyst and diffuse in 120 micrometer and 2 millimeter, respectively, in the atmosphere. We also studied nanoscopic heterogeneities in ddsorption and electron transfer processes of perylene diimide dye on TiO_2 nanoparticles, real-time single-molecule imaging of the spatial and temporal distribution of reactive oxygen species, and photocatalytic cleavage of single TiO_2/DNA nanoconjugates, as relation to solar cell, TiO_2 photocatalytic reaction mechanism at single molecule level, and DNA conjugate of TiO_2 photocatalyst.. In conclusion, our results can initiate to develop new TiO_2 photocatalyst and and the TiO_2 photocatalyst reaction system with a greatly highly efficiency and high selectivities.

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  • Molecular devices by functionalization of modified DNA

    Grant number:13305058  2001 - 2004

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    MAJIMA Tetsuro, FUJITSUKA Mamoru, TOJO Sachiko, KAWAI Kiyohiko, ENDO Masayuki

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    Grant amount:\55510000 ( Direct Cost: \42700000 、 Indirect Cost:\12810000 )

    In this research, it is aimed that various functionalities are given to modification DNA by using DNA modified covalently with various functional chromophores, controlling the functionalities can be established, and the possibility of modified DNA as molecular devices in the living body system is clarified. Especially, in order to clarify the hole transfer in DNA with respect to the construction of DNA molecular wire, photofunctions of modified DNA having photofunctional chromophores has been studied in the nano meter scale depending on the nuclear base sequences. Not only one chromophore but also several chromophores are modified on one DNA in order to clarify the charge separation, hole migration, and charge recombinataion in the nano meter scale and in the nano-pico second time scale. Technology that accurately operates functional molecule by means of molecular assembly is necessary to the nanotechnology of a bottom-up type, and it is necessary to establish the method of molecular assembly according to artificial information. DNA is the most powerful molecule where an accurate molecular assembly is achieved with many kinds of molecules and has the advantage that a variety of functional molecules can be introduced by the chemical modification in DNA. Therefore, DNA unit with the branch dividing structure was synthesized to construct a regular and rigid DNA structures based on self-assembly, and we succeeded to construct DNA nano structure to use this constructing a bridge DNA. In order to establish molecular devices by functionalization of modified DNA more precisely, to achieve the multifunction like the chlorophyll, photofunction, and complex functions is very important. It is also necessary to clarify the method of construction of modified DNA with a high performance and molecular device as a biomolecular function, and to develop the possibility of modified DNA as molecular devices in the living body system.

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  • 核酸の一電子移動、ホール移動に与える塩基対形成の影響の解明

    Grant number:12750732  2000 - 2001

    日本学術振興会  科学研究費助成事業  奨励研究(A)

    川井 清彦

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    Grant amount:\2500000 ( Direct Cost: \2500000 )

    DNAの一電子酸化ではグアニンGのラジカルカチオンが生成し、鎖切断や変異が起こる。DNAの光電子移動反応を制御することが可能になれば、DNAの位置特異的切断によるガン治療などへの応用が可能になる。このような電子移動反応の制御として、水素結合による、方法が考えられる。そこで、核酸の-電子移動、ホール移動に与える塩基対形成の影響の解明を目的に1)核酸塩基対が一電子酸化反応速度に与える影響の解明、2)塩基対の形成がホール移動速度、反応性、反応生成物に与える影響の解明、3)核酸塩基対の形成が変異原生成物に与える影響の解明について研究を行い特に核酸塩基対の形成がDNAの一電子酸化反応速度に与える影響を明らかにするとともに、水素結合によって核酸塩基の一電子酸化反応速度を制御できることを見出した。ところで、DNAでは隣り合う核酸塩基どうしのπ-スタッキングとともにG : CおよびA : T核酸塩基対間の水素結合が存在する。それぞれが電子移動反応に対してどのような効果を示すのかはわかっていない。そのためには、実験的に2つの効果を分離した系を構築するこたが必要になる。我々はDNAの光電子移動反応におよぼす水素結合の効果を明らかにするため、DNAの親水的環境を模したジクロロエタン中のG : C塩基対の光電子移動反応によるグアニンの一電子酸化反応をナノ秒レーザーフラッシュホトリシス法によって検討した。さらに、C上の置換基の電子的性質によってグアニンの光電子移動反応速度を制御できることを見出した。結論として、電子移動反応の水素結合による制御は、緑色植物光合成系IIなどの電子移動系で重要であるようにDNAの一電子酸化においても重要な役割を果たしていることがわかった。

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  • 数珠玉状および網目状フラーレン連結分子の光化学反応による生成

    Grant number:11875187  1999 - 2000

    日本学術振興会  科学研究費助成事業  萌芽的研究

    真嶋 哲朗, 佐治 幸子, 一ノ瀬 暢之, 石田 昭人, 川井 清彦

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    Grant amount:\2300000 ( Direct Cost: \2300000 )

    本研究では、有機分子の光化学反応によってビラジカルを発生させ、「ラジカルスポンジ」としてのC_<60>フラーレンに付加反応することを利用して、数珠玉状および網目状フラーレン連結分子の生成について検討した。有機光化学反応によるビラジカル発生法として、種々のシクロアルカンの環のC-C結合開裂、シクロアルカノンのアシル基のα開裂によって、アルカンのメチレン鎖を変化させることによる1,n-ビラジカルの発生、カルボニル基の分子内γ水素引き抜きによる1,4-ビラジカルの発生を、溶液中のレーザーフラッシュホトリシス法(励起レーザーとして主にXeClエキシマーレーザー308nm光を使用)によるビラジカルの過渡吸収測定から検討した。この結果、様々な原料を使用した光化学反応によって様々なビラジカルを発生させることができ、原料の有機分子の吸収にあった波長の高強度のレーザー光を照射することによって光化学反応を効率的に起こし、高密度・高濃度のビラジカルを発生させることが可能であることがわかった。次に、溶液中にC_<60>フラーレンを共存させておき、前述のXeClエキシマーレーザー励起による有機光化学反応によってビラジカルを発生させ、ビラジカルとC_<60>フラーレンとの付加反応を検討した。これら混合系では、ビラジカルの過渡吸収がC_<60>フラーレン基底状態の吸収と重なっているため、ビラジカルの過渡吸収測定は困難であった。また、C_<60>フラーレン自身もXeClエキシマーレーザー照射によって励起される。しかし、両者の濃度調整によって有機化合物の光化学反応を優先的に起こし、ビラジカルを発生させることができる場合を見い出した。実際に生成した炭素成分の質量測定によれば、数珠玉状および網目状フラーレン連結分子が生成している可能性が示唆された。

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  • ラジカルイオンにおけるスピン-電荷の非局在化

    Grant number:11133236  1999

    日本学術振興会  科学研究費助成事業  特定領域研究(A)

    真嶋 哲郎, 佐治 幸子, 一ノ瀬 暢之, 石田 昭人, 川井 清彦

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    Grant amount:\2000000 ( Direct Cost: \2000000 )

    本研究では、分子内スピン電荷混成場においてスピンと電荷とをそれぞれ原子レベルで位置選択的に局在化または非局在化、分離または接近させることによって、スピン場と電荷場との非局在電子系としての性質どのように変化するかを検討し、非局在電子系としての特徴を明らかにする。特に、スピン-正電荷の非局在化という観点からラジカルカチオンの光励起状態の発光について検討した。多くの芳香族化合物の励起一重項状態は発光性であり、それらはベンゼン環の平面性が高く、π電子の非局在化が一因となっている。電子線パルス/パルスレーザー2段階励起蛍光法(電子線パルスラジオリシス-レーザーフラッシュホトリシス法)を用いて、種々の芳香族化合物(M=ベンゼン、ナフタレン、メチルナフタレン、アントラセン、フェノール、トルエン、キシレン、メシチレン、ヘキサメチルベンゼン、アニソール、1,4ジメトキシベンゼン、1,3,5-トリメトキシベンゼン(TMB)など約50種類)のアルゴン飽和ベンゾニトリル(BN)溶液の電子線パルスラジオリシスによりそれぞれラジカルカチオン(M^<・+>)を発生させ、続いてM^<・+>の寿命内にM^<・+>の吸収にあったNd:YAGレーザーの高調波(535または355nm)を照射してM^<・+>の光励起状態を発生させ、その蛍光を観測する2段階励起蛍光法を用いて、M^<・+>の蛍光を測定した。これらの内、TMB^<・+>の蛍光が観測された(量子収率値1.1×10^<-3>)。ベンゼンのメトキシ置換体の内、TMB^<・+>のみが蛍光性を示すことを見出した。3,5-ジメトキシフェノールおよび1,3,5-トリフェノールのラジカルカチオンも蛍光を示し、量子収率は2×10^<-3>であった。結果として、M^<・+>の発光に対してM^<・+>の分子軌道のエネルギーと構造が重要であること、これはスピン-正電荷の非局在にも関係することがわかった。

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  • Studies on the Multi-responsible Molecular Systems Involving Visible Light Switching Using Radical Ions

    Grant number:09450319  1997 - 1999

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    MAJIMA Tetsuro, SAJI Sachiko, ICHINOSE Nobuyuki, ISHIDA Akito, KAWAI Kiyohiko

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    Grant amount:\3100000 ( Direct Cost: \3100000 )

    Radical ions have sharp and intense absorption bands in the visible wavelength range which depend on the structure and substituents of the radical ions. Therefore, it is suggested that radical ions can be excited by diode lasers, that undestructed reading of memory can be essentially performed with high sensitivity, and that triple memory of a molecule can be done with three independent characters of the neutral molecule and radical cation and anion of the molecule. Radical ions are used as starting material for developing of a new multiple-photoresponsible molecular system on the basis of their visile light switching characters. Since radical ions are well known to be generated from radiation reactions and are stable in the μs time scale in solution at room temperature, this study was carried out with a pulse radiolysis-laser flash photolysis combined method which is constructed at ISIR, Osaka University. Photoresponsiblity was examined through one-way photoisomerization of cis-stilbene radical cation to trans-stilbene radical cation, intermolecular electron transfer from pyrene radical anion in the photoexcited state to an electron acceptor such as bipheny1, and multiple-isomerizations of 1, 4-dipheny1-1, 3-butadiene radical cation and 1, 6-dipheny1-1, 3, 5-hexatriene radical cation. On the basis of experimental results, a new idea of multiple memory involving a neutral mlecule and the radical ions is proposed and possibility of photon-mode memory with high density is suggested by reversible reactions of radical ions. Since photoresponsible reactions of radical ions are performed in an appropriate time range after irradiation of an electron pulse, they are established to be electron-pulse gated photoresponsible reactions. Moreover, various types of molecules are synthesized to be suitable for the multi-responsible molecular systems involving visible light switching using radical ions. Radical ions of the synthetic molecular systems were used to develop new photoresponsible functional materials with high reliability and high speed from visible light as the information source.

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  • Laser Flash Photolysis and Pulse Radiolysis

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    Grant type:Competitive

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  • Chemistry of Nucleic Acid

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    Grant type:Competitive

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  • Chemistry of Radical Ions

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    Grant type:Competitive

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Teaching Experience

  • 化学概論

    Institution:大阪大学

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  • 超分子ナノバイオプロセス学

    Institution:大阪大学

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  • 励起分子化学

    Institution:大阪大学

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Social Activities

  • やさしい科学技術セミナー

    Role(s): Appearance, Presenter, Planner, Demonstrator

    国際科学技術財団・大阪大学  「光で生命を見る~研究はきらきらした芸術!~」  2012.10

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    Type:Lecture

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