著者
平川 金四郎
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.14, no.6, pp.264-274, 1972-12-25 (Released:2010-09-30)
参考文献数
31
著者
東浦 彰史 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.53, no.5, pp.332-338, 2011-10-31 (Released:2011-11-20)
参考文献数
11

Recent technical developments in macromolecular X-ray crystallography have significantly improved the resolution limit of protein structures. However, numbers of high-resolution structures are still limited. In this study, the X-ray crystal structure of bovine H-protein, a component of the glycine cleavage system, was determined at 0.88 Å resolution. This is the first ultrahigh-resolution structure of an H-protein. The data were collected using synchrotron radiation. Because of limitations of the hardware, especially the dynamic range of the CCD detector, three data sets (high-, medium- and low-resolution data sets) were measured in order to obtain a complete set of data. To improve the quality of the merged data, the reference data set was optimized for merging and the merged data were assessed by comparing merging statistics and R factors against the final model and the number of visualized hydrogen atoms. In addition, the advantages of merging three data sets were evaluated. The omission of low-resolution reflections had an adverse effect on visualization of hydrogen atoms in hydrogen-omit maps. Visualization of hydrogen electron density is a good indicator for assessing the quality of high-resolution X-ray diffraction data.

1 0 0 0 OA 表面準位

著者
平林 莞爾
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.2, pp.43-53, 1972-04-25 (Released:2010-09-30)
参考文献数
35
著者
上田 卓見 幸福 裕 竹内 恒 今井 駿輔 白石 勇太郎 嶋田 一夫
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.64, no.4, pp.279-284, 2022-12-15 (Released:2022-12-17)
参考文献数
9

NMR methods provide information about conformational dynamics of GPCRs over a wide range of frequencies in aqueous media at near-physiological temperature, with minimal modification of the wild-type GPCR covalent structures. Here we review our solution NMR studies of the functionrelated conformational dynamics of GPCRs, including β2 adrenergic receptor, μ opioid receptor, and adenosine A2A receptor.
著者
禾 晃和
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.4, pp.269-278, 2022-12-15 (Released:2022-12-17)
参考文献数
40

Protein-protein interactions are essential in diverse cellular processes including signal transduction. It is not uncommon for protein-protein interactions in the transmembrane signaling to exhibit low binding affinities with a dissociation constant in the μM range or higher. Presumably, membrane proteins can selectively bind with their binding partners via low-affinity interactions because they can only diffuse laterally in the membrane plane and interact with the partners within a limited space on the membrane surface or within the membrane. This review focuses on the crystallographic studies on cell-surface receptors and intramembrane proteases that perform the transmembrane signaling mediated by low-affinity protein-protein interactions.
著者
馬場 清喜 村川 武志
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.4, pp.285-289, 2022-12-15 (Released:2022-12-17)
参考文献数
16

It is difficult to perform the thermodynamic analysis of conformational changes occurring in protein crystals by conventional cryogenic X-ray crystallography because flash-cooled crystals have ambiguous information about temperature. We have developed a humid air and glue-coating(HAG)method in which the crystals are coated with a water-soluble polymer to control humidity. This method realized X-ray crystallographic analysis with controlled temperature and humidity in a non-cryogenic environment. In this paper, we report details of the HAG method and the thermodynamic analysis of conformational changes of copper-containing amine oxidase using the HAG method.
著者
南後 恵理子 藤原 孝彰 Luo FANGJIA 岩田 想
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.4, pp.290-293, 2022-12-15 (Released:2022-12-17)
参考文献数
19

Conventional X-ray protein crystallography captures only “static” structures due to the limitation of temporal resolution. Recently, X-ray free electron lasers(XFEL)enabled to capture dynamic structures at the atomic level with time resolutions of several tenth femtoseconds. We have been working on the development of serial femtosecond crystallography(SFX), which is a protein structure determination technique, at SACLA and successfully obtained “molecular movies” of various proteins by combining an X-ray free electron laser with a reaction trigger. This technique is suitable for tracking fast reactions such as chemical reactions because of its high temporal resolution. We will describe current advances and future prospects of molecular movies using XFEL.
著者
長谷川 和也 熊坂 崇
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.4, pp.294-299, 2022-12-15 (Released:2022-12-17)
参考文献数
34

Cryo-crystallography is usually used at synchrotron macromolecular crystallography(MX)beamlines in order to mitigate radiation damage. However, the structures determined at cryogenic temperatures sometimes hide conformational states observed at room temperature. Serial femtosecond crystallography(SFX)developed at XFELs demonstrated that room temperature structure analysis is possible even using micro-crystals. Following these successes, serial crystallography is also performed at synchrotron MX beamlines aiming at room temperature structure determination and time resolved structure analysis. In this review, synchrotron serial crystallography(SSX)performed at synchrotron MX beamlines in worldwide is summarized, and development of SSX at SPring-8 MX beamlines is introduced together with ongoing project toward time resolved experiments.
著者
齊藤 恭紀 菅 倫寛
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.4, pp.265-266, 2022-12-15 (Released:2022-12-17)
参考文献数
10
著者
小松 一生
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.190-197, 2020-08-31 (Released:2020-09-03)
参考文献数
96
被引用文献数
2 1

For recent two decades, a much greater understanding of crystal structures of ice polymorphs has developed owing to neutron diffraction under high-pressure. Here I review a brief history for the discoveries of ice polymorphs, technical developments of high-pressure neutron diffraction, and recent achievements for ice polymorphs. Remained open questions are also discussed.
著者
佐藤 弘志
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.213-218, 2022-08-31 (Released:2022-09-02)
参考文献数
19

What mechanical properties can be expected for materials composed of interlocked backbones has been a long-standing issue in materials science since the first reports on polycatenane and polyrotaxane in the 1970s. We successfully synthesized a three-dimensional porous metal-organic crystal composed of a [2] catenane. This porous crystal dynamically changes its geometry upon guest molecule release, uptake and exchange, and also upon temperature variation even in a low temperature range. We indented the crystal and obtained the Young’s moduli of 1.8 GPa in N,N-dimethylformamide, which is the lowest among those reported so far for porous metal-organic crystals.
著者
西堀 英治
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.53, no.4, pp.240-248, 2011-08-31 (Released:2011-09-15)
参考文献数
15

The crystal structure determination from powder diffraction (SDPD) has attracted wide interests for its huge potential to accelerate a design, synthesis, and characterization of the materials in the fields of nano- and bio- technologies. One of the most important progresses of the SDPD is the development of the direct-space strategy. In this report, SDPD by direct-space strategy has been described. Fundamental aspects of the strategy have been demonstrated with some examples. Global optimization methods within direct-space strategy such as Grid Search, Simulated Annealing, and Genetic Algorithm have been described including detailed methodologies.
著者
佐々木 明登
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.53, no.5, pp.312-316, 2011-10-31 (Released:2011-11-20)
参考文献数
8

Today, laboratory X-ray diffractometers are seeing increasingly wide use in the ab initio crystal structure analysis of organic powder samples. This is because optics and optical devices have been improved, making it possible to obtain precise integrated intensities of reflections in high 2-theta ranges. Another reason is that one can use direct-space methods, which do not require “high-resolution diffraction data”, much more easily than before. Described here are some key points to remember when performig ab initio crystal structure analysis using powder diffraction data from organic compounds.
著者
山内 剣
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.53, no.5, pp.307-311, 2011-10-31 (Released:2011-11-20)
参考文献数
12

Structure determination from laboratory powder diffraction data can be considered routine today as emphasized by the significant increase in the number of published structures, both organic and/or inorganic compounds solved in this way. In the past about 10 years, many significant developments in instrumentation, such as computer technology and powder diffraction methodology, allow determination of crystal structures, the size and complexity of which are only limited by data quality and computing power. New detector technologies (mostly strip detectors), faster PCs and powerful methods of structure solution (especially the direct space and the charge flipping methods) contributed most to an ever increasing success rate. Also monochromater for incident beam (like CuKα1 or MoKα1) is not always required for structure determination.
著者
橋爪 大輔
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.53, no.5, pp.299-306, 2011-10-31 (Released:2011-11-20)
参考文献数
27

Rietveld method has been widely used for structure refinements as a part of SDPD studies. In this account, practical tips on structure refinements of organic crystal are presented.
著者
池田 卓史
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.53, no.4, pp.231-239, 2011-08-31 (Released:2011-09-15)
参考文献数
39
被引用文献数
1 1

The indexing process, that is determination of unit-cell parameters, is the first important stage of the crystal structure determination from powder diffraction data (SDPD). Accurate Bragg positions (2θ or d values) of 10∼20 peaks picked up by peak-search from low 2θ angle side are indispensable for determination of lattice constants with hkl indices. Subsequently, space group can be estimated according to systematic absences based on obtained lattice constants. Integral intensities of each reflection are tentatively extracted by the whole powder pattern fitting i.e. the Le Bail or Pawley methods. Crystal structure of small organic molecule can be solved by the direct method or the charge flipping algorithm. In this report, the brief summary about indexing and whole pattern fitting was described. Furthermore, some practical examples of SDPD of small organic molecules by the direct method (EXPO2009) and the charge flipping (Superflip) were demonstrated.
著者
藤井 孝太郎 植草 秀裕
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.53, no.3, pp.170-177, 2011-06-30 (Released:2011-07-13)
参考文献数
14
被引用文献数
3 2

Techniques to prepare the sample and strategies to measure powder X-ray diffraction data for ab initio crystal structure analysis of organic and organometallic compound are shown together with an introduction to typical optics of powder X-ray diffractometry.
著者
西野 吉則 木村 隆志 鈴木 明大 城地 保昌 別所 義隆
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.1, pp.18-23, 2017-02-28 (Released:2017-03-07)
参考文献数
23

X-ray free-electron lasers (XFELs) with femtosecond pulse duration offer an innovative solution to transcend the spatial resolution limitation in conventional X-ray imaging for biological samples and soft matters by clearing up the radiation damage problem using the “diffraction-before-destruction” strategy. Building on this strategy, the authors are developing a method to image solution sample under controlled environment, pulsed coherent X-ray solution scattering (PCXSS), using XFELs and phase retrieval algorithms in coherent diffractive imaging (CDI). This article describes the basics of PCXSS and examples of PCXSS measurement, for a living cell and self-assemblies of gold nanoparticles, performed by the authors using SACLA. An attempt toward the industrial application of PCXSS is also described.