^[1]（独）理化学研究所　播磨研究所、理学電機株式会社　Ｘ線研究所　Harima Institute, RIKEN / X-ray Research Laboratory, Rigaku Corporation、^[2]（独）理化学研究所　播磨研究所　Harima Institute, RIKEN

Pages 102 - 106 Download PDF (346.48 KB)

レーザー電子光とクオーク核物理
LEPS−BL33LEP−ペンタクオークへの道
Laser Electron Photons and Quark Nuclear Physics LEPS−BL33LEP−Pentaquark

江尻　宏泰　EJIRI Hiroyasu

（財）高輝度光科学研究センター、大阪大学名誉教授　JASRI / Professor Emeritus, Osaka University

Pages 107 - 113 Download PDF (274.10 KB)

全地球マントル領域におけるMgCO₃マグネサイトの安定性と炭素の地球深部における長期的循環 Stability o MgCO₃ Magnesite Throughout the Lower Mantle and Implications for the Long-term Recycling of Carbon in the Earthﾕs Interior.

入舩　徹男　IRIFUNE Tetsuo、一色（西堀）麻衣子　ISSHIKI(NISHIBORI) Maiko

愛媛大学　地球深部ダイナミクス研究センター　Geodynamics Research Center, Ehime University

Abstract: Carbonates are important constituents of marine sediments and play an important role in the long-term recycling of carbon in the Earth’s deep interior via subduction of oceanic plates. We studied the stability of magnesite, the major carbonate in the mantle, by in situ X-ray diffraction measurements using a combination of laser-heated diamond anvil cell (LHDAC) and synchrotron radiation at BL10XU. We found that magnesite is stable at pressure up to ~115 GPa, at temperatures of ~ 2100 - 2200K, whereas it transforms to a new phase at higher pressures. The diffraction data of the new phase, magnesiteⅡ, are reasonably indexed on the basis of an orthorhombic system, yielding a density of 5.2 g/cm³ at 119 GPa, at room temperature. The present results suggest that magnesite and its high-pressure form are the major hosts for carbon throughout the most parts of the Earth’s lower mantle.

Pages 195 - 199 Download PDF (179.75 KB)

従来の常識を破るガラス構造の発見
A Study of an Unusual Glass Prepared by the Containerless Method – Glass Formation at the Limit of Insufficient Network Formers –

小原　真司　KOHARA Shinji^[1]、鈴谷　賢太郎　SUZUYA Kentaro^[2]、竹内　謙　TAKEUCHI Ken^[3]

^[1]（財）高輝度光科学研究センター　利用研究促進部門Ⅰ　Materials Science Division, JASRI、^[2]日本原子力研究所　中性子利用研究センター　Neutron Science Research Center, Japan Atomic Energy Research Institute、^[3]東京理科大学　基礎工学部　Faculty of Industrial Science and Technology, Tokyo University of Science

Abstract: Inorganic glasses normally exhibit a network of interconnected covalent-bonded structural elements that has no long-range order. In silicate glasses the network formers are based on SiO₄-tetrahedra of which the interconnectivity is realized by sharing the oxygen atoms at the corners. Conventional wisdom then implies that alkaline and alkaline-earth orthosilicate materials cannot be vitrified because they do not contain sufficient network forming SiO₂ to establish the needed interconnectivity. We have studied a bulk magnesium orthosilicate glass obtained by levitation melting- and-cooling. We find that the role of network former is largely taken on by corner- and edge-sharing ionic magnesium species that adopt 4-, 5- and 6-coordination with oxygen.

Pages 200 - 202 Download PDF (83.89 KB)

2000Bに採択され2003Aに終了した長期利用課題の研究紹介（1）
Outline of Long-term Proposals (2000B-2003A)

（財）高輝度光科学研究センター　利用業務部　User Administration Division, JASRI

Page 203 Download PDF (566.50 KB)

超臨界金属流体の構造研究
隠されていたもうひとつのゆらぎ−
Another Fluctuation in Supercritical Fluid Metals

田村　剛三郎　TAMURA Kozaburo

京都大学　工学研究科　Graduate School of Engineering, Kyoto University

Pages 203 - 213 Download PDF (566.50 KB)

放射光核共鳴散乱による元素およびサイトを特定した局所振動状態密度の研究
Study on Element-and Site-Specific Vibrational Densities of States Using Nuclear Resonant Inelastic Scattering

瀬戸　誠　SETO Makoto

京都大学　原子炉実験所　Research Reactor Institute, Kyoto University

Pages 214 - 222 Download PDF (215.55 KB)

共用ビームライン評価委員会の報告概要（平成15年度）
Report of the Public Beamline Review Committees in 2003

下村　理　SHIMOMURA Osamu

（財）高輝度光科学研究センター　研究調整部　Research Coordination Division, JASRI

Pages 253 - 256 Download PDF (25.70 KB)

藍色細菌の時計タンパク質KaiAの構造と機能機能ドメイン、X線結晶構造解析及び構造─機能相関の解明
Role of Cyanobacterial Circadian Clock Protein KaiA as Revealed by Crystal Structure

宇津巻　竜也　UZUMAKI Tatsuya^[1]、中津　亨　NAKATSU Toru^[2]、加藤　博章　KATO Hiroaki^[3]、石浦　正寛　ISHIURA Masahiro^[4]

^[1]名古屋大学　遺伝子実験施設　Center for Gene Research, Nagoya University、^[2]京都大学大学院　薬学研究科　Graduate School of Pharmaceutical Sciences, Kyoto University、^[3]京都大学大学院　薬学研究科　Graduate School of Pharmaceutical Sciences, Kyoto University、^[4]名古屋大学　遺伝子実験施設　Center for Gene Research, Nagoya University

Abstract: KaiA, KaiB, and KaiC constitute the circadian clock machinery in cyanobacteria. KaiA activates kaiBC expression while KaiC represses it. Here we demonstrated that KaiA is composed of three functional domains : the N-terminal amplitude-amplifier domain, the central period-adjuster domain, and the C-terminal clock-oscillator domain. The C-terminal domain is responsible for dimer formation, binding to KaiC, enhancing KaiC phosphorylation, and generating circadian oscillations. The 1.8 Å X-ray crystal structure of the C-terminal clock-oscillator domain of KaiA from the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1 shows that residue His270, located at the center of a KaiA dimer concavity, is essential to KaiA function. KaiA binding to KaiC likely occurs via the concave surface. Based on the structure, we could predict the structural roles of the residues that affected circadian oscillations.

Pages 367 - 371 Download PDF (219.13 KB)

BL08B2 兵庫県ビームラインの現状
Current Satus of Hyogo Beamline BL08B2

横山　和司　YOKOYAMA Kazushi

（財）ひょうご科学技術協会　Hyogo Science and Technology Association

Pages 415 - 420 Download PDF (199.65 KB)

3. 最近の研究から／FROM LATEST RESEARCH

光合成の酸素発生に関わるタンパク質の立体構造を解明
−光合成植物の進化に新たな知見−
Elucidation of the Crystal Structure of the PsbP Protein Involved in the Oxygen Evolution in Photosynthesis

伊福　健太郎　IFUKU Kentaro

京都大学大学院　生命科学研究科／（独）理化学研究所　播磨研究所　Graduate School of Biostudies, Kyoto University / Harima Institute, RIKEN

Abstract: Photosynthesis is a multi-step reaction that utilizes light energy to convert carbon dioxide into sugar and generate oxygen as by-product. The first step of photosynthesis is the oxygen-evolving reaction performed by the protein-pigment complex called “photosystem II”, and PsbP is one of the protein subunits constituting photosystem II. Since PsbP exists only in higher plants and green algae, its existence has been the subject of inquiry in the process of plant evolution. In order to elucidate the origin and function of PsbP from its 3D structure, a high-resolution analysis based on multiple wavelength anomalous dispersion method using the X-ray of SPring-8 was conducted. The result showed that the structure of PsbP was not similar to any known structures in photosystem II from cyanobacteria, primitive organisms doing oxygenic photosynthesis. This research shows one aspect of the evolution of oxygenic photosynthetic organisms.

Pages 269 -274 Download PDF (298.96 KB)

高効率熱電変換材料Zn₄Sb₃の放射光粉末法による精密構造決定
The Precise Structure Determination of High Performance Thermoelectric Material, Zn₄Sb₃, by Synchrotron Powder Diffraction.

西堀　英治　NISHIBORI Eiji

名古屋大学　工学研究科　Department of Applied Physics, Nagoya University

Abstract: The precise crystal structure of Zn₄Sb₃, which is one of the most efficient thermoelectric materials, has been determined by combination of Maximum Entropy Method and Rietveld analysis using synchrotron-radiation powder diffraction at SPring-8. The structure contains significant disorder with zinc atoms distributed over multiple positions. The crystal structure of Zn₄Sb₃ in present study allows a general explanation of the electric transport properties which explains the remarkable thermoelectric figure of merit.

Pages 421 - 424 Download PDF (111.17 KB)

EPAC2004参加＆SLS訪問記
Report on EPAC2004 and Visit to the SLS

出羽　英紀　DEWA Hideki

（財）高輝度光科学研究センター　加速器部門　Accelerator Division, JASRI

Pages 376 -378 Download PDF (34.39 KB)

文部科学省ナノテクノロジー総合支援プロジェクト
平成15年度放射光グループ研究成果報告会
「放射光利用ナノテク最前線2004」
Meeting on the Results of FY2003 Research Activities by Synchrotron Radiation Research Group of the Nano Technology Researchers Project, MEXT

研究成果報告会　プログラム委員会　Program Committee, Meeting on the Results of Research Activities

Pages 374 - 375 Download PDF (29.95 KB)

第4回SPring-8夏の学校を終えて
4th SPring-8 Summer School

鳥海　幸四郎　TORIUMI Koshiro

兵庫県立大学大学院　物質理学研究科　Graduate School of Material Science, University of Hyogo

Pages 372 - 373 Download PDF (54.60 KB)

硬X線マイクロビームを用いる顕微分光法の開発
Development of Spectromicroscopy with a Hard X-ray Microbeam

早川　慎二郎　HAYAKAWA Shinjiro

広島大学大学院　工学研究科　Graduate School of Engineering, Hiroshima University

Pages 275 - 284 Download PDF (452.72 KB)

2000Bに採択され2003Aに終了した長期利用課題の研究紹介（2）
Outline of Long-term Proposals (2000B-2003A)

（財）高輝度光科学研究センター　利用業務部　User Administration Division, JASRI

Page 275 Download PDF (452.72 KB)

脂質結合タンパク質を輸送するタンパク質、LolAとLolBの結晶構造
Crystal Structures of Bacterial Lipoprotein Localization Factors, LolA and LolB

竹田　一旗　TAKEDA Kazuki^[1]、三木　邦夫　MIKI Kunio^[2]

^[1]理化学研究所　播磨研究所　Harima Institute, RIKEN、^[2]京都大学　大学院理学研究科　Graduate School of Science, Kyoto University

Abstract: Five Lol proteins are involved in the lipoprotein transport in Gram-negative bacteria. Crystal structures of a lipoprotein-specific periplasmic chaperone, LolA, and an outer membrane lipoprotein receptor, LolB from Escherichia coli were determined using diffraction data collected at the beamlines of SPring-8. Despite their dissimilar amino acid sequences (identity ~ 8%), the structures of LolA and LolB are strikingly similar to each other. Both have a hydrophobic cavity consisting of an unclosed β-barrel and an α-helical lid. The cavity represents a possible binding site for the lipid moiety of lipoproteins. However, the structural differences in size and shape of hydrophobic inner spaces between LolA and LolB are highly connected to the functional differences between two proteins. Furthermore, these structural differences between two proteins provide significant insights into the molecular mechanisms underlying the energy-independent transfer of lipoproteins from LolA to LolB, and from LolB to the outer membrane.

Pages 30 - 35 Download PDF (226.66 KB)

時分割X線小角散乱が明らかにする蛋白質の収縮と構造形成
Compaction and Structure Formation of Proteins Revealed by Time-Resolved Small Angle X-ray Scattering

高橋　聡　TAKAHASHI Satoshi^[1]、鵜澤　尊規　UZAWA Takanori^[2]、藤澤　哲郎　FUJISAWA Tetsuro^[3]

^[1]大阪大学　蛋白質研究所　Institute for Protein Research, Osaka University、^[2]京都大学大学院　工学研究科　Graduate School of Engineering, Kyoto University、^[3]（独）理化学研究所　播磨研究所　Harima Institute, RIKEN

Abstract: The compaction process in protein folding has not been characterized well due to experimental difficulties. The submillisecond-resolved observation system for small-angle X-ray scattering was developed and applied for the process of apomyoglobin folding. It was demonstrated that the secondary and tertiary structures are largely organized cooperatively; however, the initial folding phase involves a significant collapse of their main chain structures. A common folding mechanism was proposed, in which hydrophobic environments realized by the initial collapse prompts the subsequent formation of helical structures.

Pages 265 - 268 Download PDF (128.14 KB)

ウシ心筋チトクロム酸化酵素のプロトンポンプ機構
−X線結晶学的、分子生物学的、赤外分光学的解析−
Proton Pumping Mechanism of Bovine Heart Cytochrome c Oxidase
– X-ray Crystallographical, Molecular Biological and Infrared Spectroscopical Analyses

吉川　信也　YOSHIKAWA Shinya

兵庫県立大学大学院　生命理学研究科　Graduate School of Life Science, University of Hyogo

Abstract: Improved X-ray structures of bovine heart cytochrome c oxidase (at 1.8/1.9 Å resolution in the fully oxidized/reduced states) show that the net positive charge created upon oxidation of the low-spin heme of the enzyme (heme a) drives the active proton transport from the interior of the mitochondria to Asp51 across the enzyme via a water channel and a hydrogen-bond network, located in tandem, and that the enzyme reduction induces proton ejection from the aspartate to the mitochondrial exterior. A peptide bond in the hydrogen-bond network critically inhibits reverse proton transfer through the network. A redox-coupled change in the capacity of the water channel, induced by the hydroxyfarnesylethyl group of heme a, suggests that the channel functions as an effective proton collecting region. The Asp51Asn mutation of the bovine enzyme abolishes its proton-pumping function without impairment of the dioxygen reduction activity. Infrared results indicate that the conformation of Asp51 is controlled only by the oxidation state of heme a. These results indicate that heme a drives the proton pumping process.

Pages 257 - 264 Download PDF (214.25 KB)

平成15年度の諮問委員会等の活動状況
Activities of the SPring-8 Advisory Committee and the Others in the 2003 Fiscal Year

放射光利用研究促進機構（財）高輝度光科学研究センター　企画室　Planning Office, JASRI

Pages 223 - 227 Download PDF (27.46 KB)

SPring-8の科学捜査への応用
Application of SPring-8 X-rays to Forensic Samples

二宮　利男　NINOMIYA Toshio

前兵庫県警察本部　科学捜査研究所長　Former Director, Forensic Science Laboratory, Hyogo Prefectural Police Headquarters

Pages 119 -128 Download PDF (699.87 KB)

光合成電子伝達で働く巨大分子複合体チトクロムb₆fの立体構造
Crystal Structure of Cytochrome b₆fComplex of Oxygenic Photosynthesis

栗栖　源嗣　KURISU Genji

大阪大学　蛋白質研究所　Institute for Protein Research, Osaka University

Abstract: The photosynthetic unit of oxygenic photosynthesis is organized as two large multimolecular membrane complexes, photosystem II (PSII) and photosystem I (PSI). The two photosystems operate in series linked by a third multiprotein complex called the cytochrome b₆f complex. The cytochrome b₆f complex is a membrane-spanning protein complex embedded in a thylakoide membrane of photosynthetic organisms. The b₆f complex arranges the electron transfer between plastoquinol reduced by PSII and an electron carrier protein plastocyanin that connects to PSI. The structure of the b₆f complex from cyanobacterium M. laminosus was solved at 3.0 Å resolution by isomorphous replacement method and multiwavelength anomalous diffraction from native iron atoms. The crystal structures of the cytochrome b₆f complex complete the description of the architecture of the oxygenic photosynthetic electron transport chain, since three-dimensional structures have been provided for two photosystems.

Pages 114 - 118 Download PDF (152.12 KB)

高圧下における窒化ガリウムの一致溶融
− 単結晶窒化ガリウム育成の新手法 −
Congruent Melting of Gallium Nitride at High Pressure and Its Application to Single Crystal Growth

内海　渉　UTSUMI Wataru^[1]、齋藤　寛之　SAITOH Hiroyuki^[1]、青木　勝敏　AOKI Katsutoshi^[1]、金子　洋　KANEKO Hiroshi^[2]

^[1]日本原子力研究所　関西研究所　放射光科学研究センター　Synchrotron Radiation Research Center, Kansai Research Establishment, JAERI、^[2]スプリングエイトサービス㈱　SPring-8 Service Co., Ltd

Abstract: The decomposition and melting behaviors of GaN under high pressures and temperatures were studied by in situ x-ray diffraction experiments using a large volume multi-anvil high-pressure apparatus at beamline BL14B1. GaN decomposed into Ga melt and N₂ at lower pressures than 5.5 GPa. At pressures above 6.0 GPa, however, congruent melting of GaN occurred around 2220 ℃, and decreasing the temperature allowed the GaN melt to crystallize to the original structure. Single crystals of GaN were formed by cooling the melt slowly under high pressures and were recovered at ambient conditions. The present results have great potential in providing high quality bulk single crystals of GaN, which are desirable substrates for fabricating optoelectronic devices.

Pages 42 - 45 Download PDF (148.72 KB)

シリコン同位体で色分けされたナノクラスタによる新ナノデバイスの創製の可能性
− 超伝導から量子コンピュータまで −
Possibility of New Nano Devices Using Nano Clusters Colored by Silicon Isotopes
−From Superconductors to Quantum Computers −

谷垣　勝己　TANIGAKI Katsumi^[1]、寺岡　淳二　TERAOKA Junji^[1]、伊藤　公平　ITOH Kohei^[2]、清水　智子　SHIMIZU Tomoko^[2]、守友　浩　MORITOMO Hiroshi^[3]、山中　昭司　YAMANAKA Shoji^[4]

^[1]大阪市立大学大学院　理学研究科　Graduate School of Science, Osaka City University、^[2]慶應義塾大学　理工学部　Faculty of Science and Technology, Keio University、^[3]名古屋大学大学院　工学研究科　Graduate School of Engineering, Nagoya University、^[4]広島大学大学院　工学研究科　Graduate School of Engineering, Hiroshima University

Abstract: VI^th group elements like C, Si, Ge and Sn make clusters consisting of pentagonal and/or hexagonal plolyhedra. A avarious crystals having hierachical structure can be constructed on a basis of these clusters. Recent strong demand from the field of isotope engineering for semiconductors has spurred on efforts that have led to the successful separation of stable Si isotopes. The combination of nano clusters and pure isotopes may open a new field of materials science. The present paper describnes, as such examples, the clarification of superconducting mechanism of the first discovered silicon-network Si₄₆superconductor. An approach of all silicon quantum computors using ²⁸Si isotope is also demonstrated.

Pages 36 - 41 Download PDF (256.43 KB)

RIKEN-DARESBURYシンポジウム報告
Report of the RIKEN-DARESBURY Symposium

松下　知未　MATSUSHITA Tomomi

（独）理化学研究所　播磨研究所　研究推進部　Research Promotion Division, Harima Institute, RIKEN

Pages 379 - 381 Download PDF (43.01 KB)

SRMS4報告
Report on SRMS4 International Conference

中村　哲也　NAKAMURA Tetsuya

（財）高輝度光科学研究センター　利用研究促進部門Ⅰ　Materials Science Division, JASRI

Pages 382 - 383 Download PDF (34.79 KB)

4. 研究会等報告／WORKSHOP AND COMMITTEE REPORT

RIKEN/BBSRC合同シンポジウム：日英合同膜タンパク質の構造生物学
−ハイスループット膜タンパク質結晶構造解析をめざして−
RIKEN/BBSRC Joint Symposium : Japan-UK Membrane Protein Structure Biology
−Towards High-throughput Membrane Protein Crystallography and Related Technology−

吾郷　日出夫　AGO Hideo、宮野　雅司　MIYANO Masashi

（独）理化学研究所　播磨研究所　Harima Institute, RIKEN

Pages 129 - 131 Download PDF (21.78 KB)

JAERI国際ワークショップ“Ｘ線散乱と電子構造”報告
JAERI International Workshop on“X-Ray Scattering and Electronic Structure”

五十嵐　潤一　IGARASHI Jun-ichi

日本原子力研究所　関西研究所　放射光科学研究センター　Synchrotron Radiation Research Center, Kansai Research Establishment, JAERI

Pages 132 - 134 Download PDF (23.57 KB)

ICALEPCS 2003会議報告
Report on ICALEPCS 2003

田中　良太郎　TANAKA Ryotaro

（財）高輝度光科学研究センター　加速器部門　Accelerator Division, JASRI

Pages 46 - 49 Download PDF (25.14 KB)

第14回加速器科学研究発表会に参加して
The Report on 14th Symposium on Accelerator Science and Technology

大島　隆　OHSHIMA Takashi、高野　史郎　TAKANO Shiro、張　超　ZHANG Chao、妻木　孝治　TSUMAKI Koji、松井　佐久夫　MATSUI Sakuo

（財）高輝度光科学研究センター　加速器部門　Accelerator Division, JASRI

Pages 50 - 51 Download PDF (16.34 KB)

第7回SPring-8シンポジウム
The Impression of 7th SPring-8 Symposium 2003

廣沢　一郎　HIROSAWA Ichiro

（財）高輝度光科学研究センター　利用研究促進部門Ⅰ　Materials Science Division, JASRI

Pages 52 - 54 Download PDF (19.54 KB)

SPring-8サブグループ合同ワークショップ
「X線非弾性散乱を用いた物性研究 II」報告
Joint Workshop by SPring-8 Beamlines and Research Subgroups ;
“X-ray Inelastic Scattering and Materials Science II”

岩住　俊明　IWAZUMI Toshiaki^[1]、櫻井　吉晴　SAKURAI Yoshiharu^[2]

^[1]高エネルギー加速器研究機構　物質構造科学研究所　Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK)、^[2]（財）高輝度光科学研究センター　利用研究促進部門Ⅰ　Materials Science Division, JASRI

Pages 135 - 136 Download PDF (18.56 KB)

第17回日本放射光学会年会・放射光科学合同シンポジウム報告
Report of the Joint Symposium on the 17th Annual Meeting of Japan Synchrotron Radiation Society and Synchrotron Radiation Science

高田　昌樹　TAKATA Masaki

（財）高輝度光科学研究センター　利用研究促進部門Ⅰ　Materials Science Division, JASRI

Pages 137 - 138 Download PDF (39.02 KB)

第3回CCLRC-JASRIシンポジウム
The Third CCLRC-JASRI Symposium

八木　直人　YAGI Naoto

（財）高輝度光科学研究センター　利用研究促進部門Ⅱ　Life and Environmental Science Division, JASRI

Pages 139 - 140 Download PDF (15.48 KB)

理研シンポジウム構造生物学（IX）
RIKEN Structural Biology Symposium IX at SPring-8

堀　哲哉　HORI Tetsuya、宮野　雅司　MIYANO Masashi

（独）理化学研究所　播磨研究所　Harima Institute, RIKEN