Volume 08（2003）
（財）高輝度光科学研究センター 副理事長、放射光研究所長 Director General of Synchrotron Radiation Research Laboratory, Vice President of JASRI
（財）高輝度光科学研究センター 副理事長、放射光研究所長 Director General of Synchrotron Radiation Research Laboratory, Vice President of JASRI
（財）高輝度光科学研究センター 副理事長、放射光研究所長 Director General of Synchrotron Radiation Research Laboratory, Vice President of JASRI
（財）高輝度光科学研究センター 副理事長、放射光研究所長 Director General of Synchrotron Radiation Research Laboratory, Vice President of JASRI
(財)高輝度光科学研究センター 副理事長、放射光研究所長 JASRI Vice President, Director of JASRI Research Sector
(財)高輝度光科学研究センター 副理事長、放射光研究所長 JASRI Vice President, Director of JASRI Research Sector
1. SPring-8の現状／PRESENT STATUS OF SPring-8
（財）高輝度光科学研究センター 所長室 計画調整グループ Planning and Coordination Section, Directorﾕs Office, JASRI
東京工業大学 応用セラミックス研究所 Materials and Structures Laboratory, Tokyo Institute of Technology
2. 最近の研究から／FROM LATEST RESEARCH
[1](財)高輝度光科学研究センター 放射光研究所 JASRI Synchrotron Radiation Research Laboratory
[2]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, JAERI Kansai Research Establishment
- Abstract
- With the arrival of the latest generation of synchrotron sources and the introduction of advanced insertion devices (wigglers and undulators), the high-energy (E >=30 keV) X-ray diffraction technique has become feasible, leading to new approaches in the quantitative study of the structure of disordered materials. High-energy X-ray diffraction has several advantages: higher resolution in real space due to a wide range of scattering vector Q, smaller correction terms (especially the absorption correction), reduction of truncation errors, the feasibility of running under extreme environments, including high-temperatures and high-pressures, and the ability to make direct comparisons between X-ray and neutron diffraction data. Recently, high-energy X-ray diffraction data have been combined with neutron diffraction data from a pulsed source to provide more detailed and reliable structural information than that hitherto available. This article reviews and summarizes recent results obtained from the high-energy X-ray diffraction on glass, liquid, amorphus and crystalline materials using bending magnet beamlines at SPring-8.
(財)高輝度光科学研究センター 利用研究促進部門Ⅱ JASRI Life and Environment Science Division
- Abstract
- By using the combination of intense X-ray beams from an undulator-based beamline at SPring-8 (BL45XU) and a microbeam optics, we were able to record X-ray diffraction patterns from single myofibrils of a striated muscle (bumblebee flight muscle). Unlike in the conventional method, the muscle cell was irradiated end-on, so that a diffraction pattern from a myofibril was recorded without isolating it from the cell. The recorded pattern consisted of a number of hexagonally arranged spot-like reflections, clearly indicating that the reflections originated from a single hexagonal lattice of myofilaments. Since the muscle cells used were ~3 mm long and contained 1000+ sarcomeres connected in series, the result means that the lattices in these sarcomeres are exactly in register. The achievement opens the possibility that the X-ray diffraction technique may be applied to other micrometer-sized protein assemblies in the cell, such as axonemes and mitotic spindles.
大阪大学 核物理研究センター RCNP, Osaka University
- Abstract
- The GeV photon beam at BL33LEP is produced by backward-Compton scattering of laser photons from 8 GeV electrons. Polarization of the photon beam is nearly 100 % at the maximum energy with fully polarized laser photons. We report the status of the project and some results from first physics run with this high quality beam.
（財）高輝度光科学研究センター 加速器部門 Accelerator Division, JASRI
- Abstract
- In order to make the beam intensity in each rf bucket in the storage ring uniform, we developed a new synchronization method to synchronize two rf’s of 2856 MHz for the linac and 508.58 MHz for the storage ring. This method can be applied to any combination of arbitrary different rf’s. The method is briefly described.
[1]国立循環器病センター研究所 心臓生理部 Department of Cardiac Physiology, National Cardiovascular Center Research Institute、[2]理化学研究所 播磨研究所 構造生物化学研究室 Laboratory of Structural Biochemistry, Riken Harima Institute
- Abstract
- Troponin (Tn) plays key roles in the Ca2+ regulation of skeletal and cardiac muscle contraction. It consists of three subunits (TnT, TnC and TnI), and, together with tropomyosin (Tm), is located on the actin filament. We have solved crystal structures of the core domains (relative molecular mass of 46kDa and 52kDa) of human cardiac Tn in the Ca2+-saturated form. The structures reveal that the core domain is further divided into structurally distinct sub-domains that are connected by flexible linkers, making the entire molecule highly flexible. The α-helical coiled-coil formed between TnT and TnI is integrated in a rigid and asymmetric structure (about 80Å long), the IT-arm, which bridges putative Tm-anchoring regions. The structures of Tn ternary complex imply that the Ca2+-binding to the regulatory site of TnC removes the C-terminal portion of TnI from actin/Tm, thereby alters the flexibility of Tn/Tm on the actin filament.
東京大学大学院 理学系研究科 Graduate School of Science, The University of Tokyo
- Abstract
- The archaeal/eukaryotic tyrosyl-tRNA synthetase (TyrRS)–tRNATyr pairs do not cross-react with their bacterial counterparts. This ‘orthogonal’ condition is essential for using the archaeal pair to expand the bacterial genetic code. We solved the 1.95 Å-resolution structure of an archaeal TyrRS–tRNATyr–L-tyrosine complex by using the X-ray diffraction data sets collected at the beamline BL41XU, SPring-8. This structure reveals that this archaeal TyrRS strictly recognizes the C1:G72 base pair, whereas the bacterial TyrRS recognizes the G1:C72 in a different manner using different residues. These diverse tRNA recognition modes form the basis for the orthogonality.
[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]（財）高輝度光科学研究センター ビームライン・技術部門 Beamline Division, JASRI、[3]理化学研究所 播磨研究所 Harima Institute, RIKEN
- Abstract
- The performance of sagittal focusing for hard X-rays with a cylindrical bent crystal at the SPring-8 is described. The bending mechanism is designed for the SPring-8 standard bending-magnet beamlines. Two-dimensional focusing is achievable by combining sagittal horizontal focusing and vertical focusing mirror. The results underline that the two-dimensional focusing was achieved in the wide energy range by using an adjustable-inclined double crystal monochromator.
姫路工業大学大学院 理学研究科 Himeji Institute of Technology, Graduate School and Faculty of Science
- Abstract
- For photo-excited crystallography at low temperature using micro-crystals, a new low-temperature vacuum X-ray camera (LTV camera) has been developed and installed at SPring-8 BL02B1. By eliminating X-ray scattering from air and vacuum windows, we successfully obtained high quality data below 80K. we have also developed a special data collection system, multiple exposure IP method, by which both diffraction patterns from the crystal on light irradiated and unirradiated conditions can be recorded on the same image of an IP detector.
Molecular distortion of a photo-excited diplatinum(II) complex in a single crystal has been directly observed by accurate synchrotron radiation studies using the LTV camera and multiple exposure IP method. Photo-excited crystallographic analysis has revealed that a small portion of [Pt2(pop)4]4- (pop=H2O5P22-) complex shows the Pt-Pt bond shrinkage of 0.23 Å under blue laser irradiation.
3. 研究会等報告／WORKSHOP AND COMMITTEE REPORT
放射光利用研究促進機構（財）高輝度光科学研究センター 企画調査部 Organization for the Promotion of Synchrotron Radiation Research . Research and Planning Division, JASRI
東京大学大学院 理学系研究科 Graduate School of Science, The University of Tokyo
- Abstract
- Transfer RNA (tRNA) canonically has the clover-leaf secondary structure with the acceptor, D, anticodon, and T arms, which are folded into the L-shaped tertiary structure. To strengthen the L form, post-transcriptional modifications occur on nucleotides buried within the core, but the modification enzymes are paradoxically inaccessible to them in the L form. In this study, we determined the crystal structure of tRNA bound with archaeosine tRNA-guanine transglycosylase, which modifies G15 of the D arm in the core, by using the X-ray diffraction data set collected at BL41XU, SPring-8. The bound tRNA assumes an alternative conformation (“λform”) drastically different from the L form. All of the D arm secondary base pairs and the canonical tertiary interactions are disrupted. Furthermore, a helical structure is reorganized, while the rest of the D arm is single-stranded and protruded. Consequently, the enzyme precisely locates the exposed G15 in the active site, by counting the nucleotide number from G1 to G15 in the λform.
[1]（財）高輝度光科学研究センター 利用研究促進部門Ⅰ Material Science Division, JASRI、[2]京都大学大学院 工学研究科 Graduate School of Engineering, Kyoto University、[3]大阪女子大学 理学部 Faculty of Science, Osaka Women's University、[4]岡山大学 理学部 Faculty of Science, Okayama University、[5]大阪大学 極限科学研究センター Research Center for Materials Science at Extreme Conditions, Osaka University、[6]名古屋大学大学院 工学研究科 Graduate School of Engineering, Nagoya University
- Abstract
- We report the direct observation of dioxygen molecules physisorbed in the nanochannels of a microporous copper coordination polymer by the MEM (maximum entropy method)/Rietveld method, using in situ high-resolution synchrotron x-ray powder diffraction measurements. The obtained MEM electron density revealed that van der Waals dimers of physisorbed O2 locate in the middle of nanochannels and form a one-dimensional ladder structure aligned to the host channel structure. The observed magnetic susceptibilities is characteristic of the confined O2 molecules in one-dimensional nanochannels of CPL-1 (coordination polymer 1 with pillared layer structure).
[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]理化学研究所 播磨研究所 Harima Institute, RIKEN、[3]横浜市立大学大学院 総合理学研究科 Graduate School of Integrated Science, Yokohama City University、[4]自治医科大学 生理学講座 Department of Physiology, Jichi Medical School
- Abstract
- Proteins are encoded in genes and play a wide variety of functions in life. Three dimensional (3-D) protein structures, determined by conventional X-ray crystallographic technique and also by multidimensional nuclear magnetic resonance (NMR) spectroscopy, have provided a solid base for understanding their 3-D architecture. However, relatively little information has been extracted from these studies about how the proteins do their tasks, because the 3-D structural information is essentially static. To understand the mechanistic details of how proteins function, it is crucial to know the dynamic features of the events that give rise to their designed functions. We have been working on cryogenic trapping technique of photoactive intermediates of proteins at the BL44B2, SPring-8, and here we present our experimental setup and direct observation of photo-induced tertiary structural changes in human hemoglobin.
研究成果報告会 プログラム委員会 Program Committee, Meeting on the Results of Research Actirities
姫路工業大学大学院 理学研究科 Graduate School and Faculty of Science, Himeji Institute of Technology
（財）高輝度光科学研究センター 所長室 研究事務グループ Research Secretariat, Director’s Office, JASRI
新潟大学 教育人間科学部 Faculty of Education and Human Sciences, Niigata University
日本原子力研究所 放射光科学研究センター Synchrotron Radiation Research Center, JAERI
(財)高輝度光科学研究センター 利用研究促進部門 JASRI Life and Environment Science Division
姫路工業大学大学院 理学研究科 Himeji Institute of Technology, Graduate School and Faculty of Science
[1]東京大学 物性研究所 Institute for Solid State Physics, the University of Tokyo、
[2]姫路工業大学大学院 理学研究科 Himeji Institute of Technology, Graduate School and Faculty of Science
大阪大学大学院 基礎工学研究科 Graduate School of Engineering Science, Osaka University
理化学研究所 播磨研究所 構造生物化学研究室 RIKEN Harima Institute at SPring-8,Lab of Structural Biochemistry
4. 播磨科学公園都市ガイドブック／HANDY TIPS AROUND HARIMA SCIENCE GARDEN CITY
SPring-8利用者懇談会 会長 名古屋大学大学院 工学研究科 Graduate School of Engineering,Nagoya University
（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
三菱電機㈱ 先端技術総合研究所 Advanced Technology R&D Center, Mitsubishi Electric Co.
（財）高輝度光科学研究センター 広報室 Public Relations Office, JASRI
