Journal of the Crystallographic Society of Japan
Volume 51 (3), 2009.

J. Cryst. Soc. Jpn., 51(3), 189-194 (2009).
X-ray Crystal Structure of the Vault, Largest Ribonucleoprotein Particle, with a Molecular Weight of 10 MDa
Hideaki TANAKA1 , Koji KATO2 and Eiki YAMASHITA3
Affilication: 1, 2, 3Institute for Protein Research, Osaka University
Address: 1, 2, 33-2 Yamada-Oka, Suita, Osaka 565-0871, Japan
E-Mail: 1tana(%), 2k-kato(%), 3eiki(%)

Vaults are among the largest cytoplasmic ribonucleoprotein particles and are found in numerous eukaryotic species. Although roles in multidrug resistance and innate immunity have been suggested, the cellular function remains unclear. We have determined the X-ray structure of rat liver vault at 3.5 šresolution. A vault particle shell was composed of 78 MVP(Major vault protein)chains with 39-fold dihedral symmetry. The shoulder domain of MVP is structurally similar to SPFH(stomatin/prohibitin/flotillin/HflK/C)domain involved in lipid raft association.

J. Cryst. Soc. Jpn., 51(3), 195-200 (2009).
Crystal Structure Analysis of Human Glutamine : Fructose 6-Phosphate Amidotransferase, a Key Regulator in Type 2 Diabetes
Yuichiro NAKAISHI1 and Masahiko BANDO2
Affilication: 1, 2Medicinal Chemistry Research Institute, Otsuka Pharmaceutical Co., Ltd.
Address: 1, 2463-10 Kagasuno, Kawauchi-cho, Tokushima 771-0192, Japan
E-Mail: 1y_nakaishi(%), 2m_bando(%)

Glutamine : fructose 6-phosphate amidotransferase(GFAT)is a rate-limiting enzyme in the hexoamine biosythetic pathway and plays an important role in type 2 diabetes. We now report the first structures of the isomerase domain of the human GFAT in the presence of cyclic glucose 6-phosphate and linear glucosamine 6-phosphate. The C-terminal tail including the active site displays a rigid conformation, similar to the corresponding Escherichia coli enzyme. The diversity of the CF helix near the active site suggests the helix is a major target for drug design. Our study provides insights into the development of therapeutic drugs for type 2 diabetes.

J. Cryst. Soc. Jpn., 51(3), 201-204 (2009).
Structure Analysis of a Submicrometer-Scale Single Powder Grain by the Pinpoint Structural Measurement
Nobuhiro YASUDA1 , Haruno MURAYAMA2 , Yoshimitsu FUKUYAMA3 , Jungeun KIM4 and Shigeru KIMURA5
Affilication: 1, 3, 4, 5Research & Utilization Division, Japan Synchrotron Radiation Research Institute, 2Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University
Address: 1, 3, 4, 51-1-1 Kouto, Sayo, Sayo, Hyogo 679-5198, Japan, 21-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
E-Mail: 1nyasuda(%), 2harunoch(%), 3yfukuya(%), 4kimj(%), 5kimuras(%)

A high-precision diffractometer has been developed for the structure analysis of a submicrometer-scale single grain of a powder sample at the SPring-8 BL40XU undulator beamline. A stable focused synchrotron radiation beam with the phase zone plate and a low eccentric goniometer are the key techniques for measuring accurate diffraction intensity data of a submicrometer-scale single powder grain. In order to verify the performance of the diffractometer, the diffraction pattern data of several submicrometer-scale BaTiO3 grains, with dimensions of 600~600~300 nm, were measured. By identifying the diffraction data set of one single powder grain, the crystal structure was successfully determined. The features of the high-precision diffractometer and the result of the structure analysis of a submicrometer-scale BaTiO3 single powder grain are described.

J. Cryst. Soc. Jpn., 51(3), 205-210 (2009).
Investigations on Photo-Induced Phase Transitions by Means of a Charge Density Analysis using Synchrotron Radiation
Kenichi KATO1 and Yutaka MORITOMO2
Affilication: 1Structural Materials Science Laboratory, RIKEN SPring-8 Center, 2Department of Physics, University of Tsukuba
Address: 11-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan, 21-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan
E-Mail: 1katok(%), 2moritomo(%)

Charge density studies of photo-induced phase transition materials have been carried out by means of synchrotron radiation powder diffractometry. We found that the photo-excited HS phase in one of spin crossover complexes was distinctly different from both the ground LS and the thermally induced HS phases in a charge density level. The weak electrostatic interaction derived from the suppressed charge density between Fe and N in the photo-excited state should be an origin of the faster relaxation process than the conventional LIESST phenomenon.

J. Cryst. Soc. Jpn., 51(3), 211-217 (2009).
Self-Assembled Metallo-Supermolecules with Motional Functions
Shuichi HIRAOKA1 and Mitsuhiko Shionoya2
Affilication: 1, 2Graduate School of Science, The University of Tokyo
Address: 1, 27-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
E-Mail: 1hiraoka(%), 2shionoya(%)

In this account, the construction of metallo-supermolecules that behave like machinery is described. A trinuclear Ag(I)-molecular ball bearing is a ligand exchange-driven molecular device. In this complex, two rotor molecules are connected and coaxially arranged by three Ag(I)ions and they can freely rotate relative to each other though cooperative ligand exchange reactions around Ag(I)ions. Furthermore, for a long-range transmission of rotational motion between two rotors 1.5 nm apart from each other, a helical transmitter that can precisely correlate the motions of two terminal rotors was successfully constructed. The motions of two rotors connected with both sides of the transmitter were proven to strongly correlate with each other through a cascade helix inversion of the central transmitter. The structures of these entities were characterized by solution-phase NMR and mass measurements and by a single-crystal X-ray analysis. Moreover, the motions of these supermolecules in solution were analyzed by variable-temperature 1H NMR spectroscopy.

J. Cryst. Soc. Jpn., 51(3), 218-224 (2009).
Release of SoftwareiYadokari-XG 2009jfor Crystal Structure Analyses
Chizuko KABUTO1 , Shigehisa AKINE2 and Eunsang KWON3
Affilication: 1G-COE, Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 2Graduate School of Pure and Applied Sciences, University of Tsukuba, 3Research and Analytical Center for Giant Molecules, Graduate School of Science, Tohoku University
Address: 16-6-07 Aramaki, Aoba-ku, Sendai 980-8579, Japan, 21-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan, 36-3 Aramakiazaaoba, Aoba-ku, Sendai 980-8578, Japan
E-Mail: 1ckabuto(%), 2akine(%), 3ekwon(%)

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