著者
古谷野 哲夫
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.56, no.5, pp.319-322, 2014-10-31 (Released:2014-10-31)
参考文献数
6
被引用文献数
1

Chocolate consists of solid particles such as cocoa, sugar, and milk solids which are dispersed in a continuous fat phase. The major fat in chocolate is cocoa butter, and it is crystallized at room temperature, so chocolate is a food which we eat crystals. Therefore, fat crystals play a great role in chocolate quality and storage stability. In this paper, polymorphism of cocoa butter and the transformation of polymorphic forms are reviewed including recent results.
著者
大橋 裕二
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.57, no.2, pp.131-133, 2015-04-30 (Released:2015-04-30)
参考文献数
17
被引用文献数
1

76 0 0 0 OA 学術会議の改革

著者
郷 信広
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.45, no.5, pp.341-343, 2003-10-29 (Released:2010-09-30)
参考文献数
4
著者
中根 崇智
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.64, no.2, pp.125-131, 2022-05-31 (Released:2022-06-01)
参考文献数
16

The past decade has seen revolutionary progress in single particle analysis with cryo-electron microscopes. Steady improvement in resolution has culminated in the reports of atomic resolution(1.2 Å)structures of apoferritin in 2020. This review, as a follow-up to my previous review in 2018, summarizes hardware and software improvements that enabled this milestone achievement. A quantitative analysis of the relationship between the number of particles and the resolution is presented and its practical implication in data collection strategies is discussed.
著者
志甫谷 渉
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.62, no.3, pp.143-149, 2020-08-31 (Released:2020-09-03)
参考文献数
10

Endothelin receptors(ETA and ETB)are G-protein-coupled receptors activated by endothelin-1 and are involved in blood pressure regulation. Using the microfocus beamline BL32XU at SPring-8, we determined 8 crystal structures of human ETB receptor, revealing the drug binding modes and receptor activation mechanism.
著者
中根 崇智
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.60, no.5-6, pp.230-232, 2018-12-15 (Released:2018-12-19)
参考文献数
9
著者
安達 成彦
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.63, no.4, pp.267-272, 2021-12-15 (Released:2021-12-18)
参考文献数
11

In March 2018, KEK obtained a 200 kV cryogenic electron microscopy(cryo-EM; a Talos Arctica G2 with a Falcon 3EC direct electron detector)and prepared a pipeline for solving high-resolution structures of macromolecular biomolecules, such as proteins, DNA, and RNA. In October 2018, the cryo-EM facility in KEK opened to academic and industrial users. Our mission is three-fold:to provide cryo-EM machine time for external users, to support grid-prep and data collection(and single particle analysis, if needed), and to help users acquire cryo-EM skills. One remarkable result is the single-particle analysis of an 860-kDa enzyme at 2.05 angstrom resolution, which suggested that we had established a proper protocol for cryo-EM operation and single-particle analysis. We will continue to support external users and carry out cryo-EM single particle analysis of macromolecular biomolecules.
著者
坂部 知平
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.61, no.2, pp.138-140, 2019-05-31 (Released:2019-06-05)
参考文献数
4
著者
竹田 一旗 丹羽 智美 三木 邦夫
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.57, no.2, pp.104-109, 2015-04-30 (Released:2015-04-30)
参考文献数
18

For efficient use of sunlight, the light-harvesting core antenna (LH1) and the reaction center (RC) form a supramolecular complex (LH1-RC) in photosynthetic bacteria. We determined the crystal structure of a LH1-RC complex from a purple bacterium, Thermochromatium tepidum. The structure reveals that the RC is completely surrounded by 16 αβ-heterodimers. Calcium ions are bound at the periplasmic side of LH1. 32 bacteriochlorophyll and 16 spirilloxanthin molecules form an elliptical assembly in LH1. The pigment geometry involved in the absorption characteristics and excitation energy transfer is determined. In addition, ubiquinone channels and lipid molecules are observed in the complex.
著者
中川 敦史
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.35, no.5, pp.327-333, 1993-10-25 (Released:2010-09-30)
参考文献数
21
被引用文献数
3 5

Flower colors, from red through purple to blue, are mostly from anthocyanins. Although there are many colors, only a few anthocyanins are found. We have succeeded to solve the structure of real anthocyanin and a sugar containing flavonoid, Cd-commelinin, using the Weissenberg camera for macromolecular crystallography with imaging plates at the Photon Factory. The blue flower-color development and the stability of the color can be explained by metal complexation of anthocyanin and intermolecular hydrophobic association. Commelinin is a new type of stoichiometric supramolecule, which consists of low molecular mass components.
著者
今崎 剛 高木 雄一郎
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.54, no.5, pp.292-299, 2012-10-31 (Released:2012-11-06)
参考文献数
13

Deciphering structures of the multi-protein complexes is vital to understand biology. However, the large size, complexity, heterogeneity, and typically low abundance in their native sources, have often precluded successful structural analysis of the multi-protein machines. We have determined the crystal structure of the Mediator Head module (7 subunits, 223 kDa), an essential component in RNA polymerase II transcription. Our success depended on addressing series of challenges unique to structure determination of multi-protein complexes. We anticipate that our approach will serve as a paradigm for structural analysis of the eukaryotic multi-protein complexes that regulate vital cellular processes in the future.
著者
山下 恵太郎
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.64, no.2, pp.118-124, 2022-05-31 (Released:2022-06-01)
参考文献数
15

Atomic model refinement and map calculation methods for cryo-EM single particle analysis(SPA)are explained in relation to X-ray crystallography. To make the best use of high-resolution reconstructions from SPA, it is important to calculate interpretable density maps to help build atomic models, and to use all experimental information to refine models. We developed a new program Servalcat to facilitate the structure refinement in reciprocal space. Servalcat performs structure refinement using REFMAC5, followed by calculation of weighted and sharpened Fo and Fo-Fc maps, which are useful in manual model rebuilding.
著者
木下 誉富
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.59, no.4, pp.174-181, 2017-08-31 (Released:2017-08-31)
参考文献数
17
被引用文献数
1

Protein kinases transfer the γ-phosphate group of ATP to the hydroxyl group of substrate protein. 518 human kinases are classified into serine/threonine kinases and tyrosine kinases, and individually and/or synergistically transduce physiologic stimuli into cell to promote cell proliferation or apoptosis, etc. Kinases are identified as drug targets because dysfunction of kinases leads to severe diseases such as cancers. In this review, I describe structural biology on kinases and drug discovery for the severe diseases such as cancers due to kinase dysfunction.
著者
緒方 英明
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.63, no.2, pp.97-104, 2021-05-31 (Released:2021-06-05)
参考文献数
32

The metalloenzyme ‘hydrogenase’ catalyzes the reversible oxidation of dihydrogen. Crystallographic structures of[NiFe]hydrogenases from sulfate-reducing bacteria have been determined and give detailed insight into pathways for the transfer of electrons, protons and hydrogen molecules.[NiFe]hydrogenases contain one nickel and one iron in the active site, the latter carries non-protein diatomic ligands, one CO and two CN-s. A possible catalytic mechanism of the oxygen-sensitive[NiFe]hydrogenases for the heterolytic dihydrogen splitting is proposed.
著者
吉田 徹 山田 等仁 津下 英明
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.64, no.1, pp.69-76, 2022-02-28 (Released:2022-03-04)
参考文献数
20

The iota toxin produced by Clostridium perfringens type E is a binary toxin comprising two independent polypeptides:Ia, an ADP-ribosyltransferase, and Ib, which is involved in cell binding and translocation of Ia across the cell membrane. Binary toxin family includes C. perfringens iota toxin, C. difficile CDT, C. spiroforme CST, C. botulinum C2, and B. anthracis anthrax toxin. Here we introduce the binary toxin complex structures using single-particle Cryo-EM structural analysis and the structural basis of toxin translocation system.

7 0 0 0 OA 学会ニュース

出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.56, no.3, pp.News3-News3, 2014-06-30 (Released:2014-07-09)
著者
池田 拓史 門馬 綱一
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.64, no.3, pp.238-239, 2022-08-31 (Released:2022-09-02)
著者
ネスポロ マッシモ
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.59, no.4, pp.150-158, 2017-08-31 (Released:2017-08-31)
参考文献数
14
被引用文献数
2
著者
草野 圭弘 福原 実
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.56, no.3, pp.179-185, 2014-06-30 (Released:2014-07-09)
参考文献数
25

Bizen stoneware, with the characteristic reddish hidasuki or “fire-marked” pattern, is one of Japan's best known traditional ceramic works of art. We investigated the microstructure and color-formation process in Bizen stoneware, and discovered that the hidasuki pattern resulted from the precipitation of corundum (α-Al2O3) and the subsequent epitaxial growth of hematite (α-Fe2O3) around it in a ~50 µm-thick liquid specifically formed in the ceramic surface. The epitaxial composites include hexagonal plate-like α-Fe2O3/α-Al2O3/α-Fe2O3 sandwiched particles. At low oxygen partial pressures, α-Fe coated graphite, Fe3P and ε-Fe2O3 were also formed to appear.