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
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
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
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
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 4

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
冨田 研一
出版者
The Crystallographic Society of Japan
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.23, no.5, pp.289-298, 1981-09-30 (Released:2010-09-30)
参考文献数
36

The recent progress in single crystal X-ray analysis of DNA fragments involving the oligomers having alternating cytosine-guanine base sequence and novel left-handed double-stranded helical structure is reviewed and all the possible requisite conditions for providing the handedness of DNA structure are also evaluated.
著者
神山 崇
出版者
The Crystallographic Society of Japan
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.40, no.5, pp.301-307, 1998-10-31 (Released:2010-09-30)
参考文献数
17

入門講座「結晶学の原点を読む」の第2回目は, リートベルト法です.粉末回折法で構造を決定する非常に有力な手段であるリートベルト法は, 現在非常に多くの利用者がおり, 結晶学の分野では欠かせない解析法となっています.この方法の原理は非常に簡単であり, 測定された粉末回折の強度データのパターンと構造モデルから計算された強度のパターンが一致するように最小自乗法でパラメーターを求めるだけです.このように簡単な原理からなっているにもかかわらず, 計算機のプログラムは非常に複雑で多岐に渡っており, 使用している方々のほとんどにとってそのプログラムの中身はまったくブラックボックスであり, かつ出力された結果に対する吟味もどのようにしたら良いかあまりわからず使っている感があります.また, リートベルト自身によるさまざまな物質への適用例は施設報告が多く手に入りにくいものです.そのような中には, 現在の単結晶の実験からみて明らかに間違った結果を出している例も見られます.これも, 当時の技術力と言うよりは, 相転移のような微妙な構造変化の問題を取扱う時, リートベルト法は非常に注意が必要であると言う今日的な問題です.これら, 粉末回折でのリートベルト法の有利な点や適用範囲は何か, また, リートベルト自身がどのような問題点や注意点がこの方法にあると考えていたのかを原著論文で見ることは大変意義があると言えます.今回は, J. Appl. Cryst.に投稿されたリートベルト法の原点とも言える論文を易しく解説していただきます.

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
秋光 純 富本 晃吉
出版者
The Crystallographic Society of Japan
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.34, no.5, pp.273-282, 1992-10-30 (Released:2010-09-30)
参考文献数
26

The current status of oxide superconductors is briefly reviewed from a crystal structure perspective. Tokura et al. recently classified high-temperature superconductors using block layer concept. We propose a new “layer” concept and discuss the possibility of new block layers by reconstructing the layers. As an example, we present new high-Tc materials containing CO3 by combining an “old” and new block layers recently discovered. Finally, main roles for realizing the high-Tc superconductors are discussed from the structural point of view.
著者
大場 茂
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.6, pp.284-292, 2017-12-31 (Released:2017-12-31)
参考文献数
14

SHELXT is a revolutionary program which solves the structure assuming space group P1, and determines the space group type based on the assigned Laue group and calculated P1 phase angles. The background and procedures of the computation will be summarized, and important points to check the results will be noted.
著者
都築 誠二 本田 一匡
出版者
The Crystallographic Society of Japan
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.46, no.2, pp.165-171, 2004-04-30 (Released:2010-09-30)
参考文献数
27

Ab initio molecular orbital calculation is becoming a powerful tool for studying inter-molecular interactions in crystals. The effects of basis set and electron correlation and the performance of density functional methods are reviewed. Model chemistry calculations and classification of intermolecular interactions are briefly mentioned. Some examples of high-level ab initio computations of intermolecular interactions are also presented.
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.

5 0 0 0 OA 氷の相転移

著者
東 晃
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.14, no.6, pp.274-285, 1972-12-25 (Released:2010-09-30)
参考文献数
37
被引用文献数
2
著者
近藤 次郎
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.60, no.2-3, pp.121-128, 2018-05-31 (Released:2018-06-02)
参考文献数
23

DNA is very attractive as bio-nanomaterials, since it is chemically stable, biocompatible, less toxic, environmentally friendly and easy to synthesize. In addition, the discovery of metal-mediated base pairs, such as T-Hg(II)-T and C-A(gI)-C, has inspired scientists to develop several nanodevices including heavy metal sensor and trapping beads. Recently, we have successfully developed a silver-DNA hybrid nanowire composed only of silver-mediated base pairs, in which Ag(I)make uninterrupted one-dimensional array along the DNA helical axis. In addition, its structure was solved by high-resolution X-ray crystallography. In this article, I present a variety of complicated and beautiful DNA structures and discuss the future outlook of “DNA structural bio-nanotechnology”.
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
竹内 慶夫
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.27, no.1, pp.40-46, 1985-01-30 (Released:2010-09-30)
参考文献数
5
被引用文献数
1
著者
松垣 直宏 山田 悠介 引田 理英 平木 雅彦 千田 美紀 千田 俊哉
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.1, pp.56-61, 2020-02-29 (Released:2020-03-06)
参考文献数
21

Applying long wavelength X-ray (ca. longer than 2 Å) in macromolecular crystallography has been limited due to the lack of dedicated measurement environment. Photon Factory BL-1A, as an MX beamline optimized for diffraction experiment using the wavelength from 2.7 to 3.3 Å, offers the opportunity to routinely perform data collection for Native SAD phasing or light atoms identification with much sophisticated manner. Sample optimization is another key for successful experiment at the wavelength where severe absorption is inevitable. We describe how the difficulties in use of long wavelength X-ray were overcome at the beamline and the auxiliary facility, as well as the current results of Native SAD phasing.