Studies on Structure Analysis of the Molecules with a few Thousand Molecular Weights

芦田、安冈、海和竹中博士将蛋白晶体的X射线结构分析方法应用于分子量为几千的分子，建立了改进电子密度的低分辨率傅立叶图的方法，证明了利用同步辐射的多波长反常色散技术的有效性，并证明了“MERLOT”程序对分子置换法的有用性。Fujii博士展示了“MERLOT”用于寡核苷酸晶体的X射线分析和“XPLOR”用于结构细化的分子动力学的有用性。Ishida博士认为，通过ROESY方法从质子NMR数据中获得的初始结构对于X射线晶体结构分析的初始模型结构是有用的。Okuyama博士确定了一系列含有α-氨基异丁酸的肽结构，并讨论了决定螺旋类型的因素。Hata博士将蛋白质工程应用于耐热肠毒素，并解决了其分子结构问题。Iwasaki博士表示，“SHELXS 76”对于优化无序结构是有用的。大场博士发现了分子力学计算对无序结构的有用性。Ohashi博士成功地确定了晶体中外消旋反应任何阶段的晶体结构。Itai博士发现了基于受体结构的候选药物结构的自动创建方法，并开发了程序“LEGEND”。大泽博士编写了晶体中分子力学计算的程序，并讨论了溶液中的算法。伊藤博士和大场博士试图解决一种植物色素鸭跖草素的结构，并获得了许多有用的知识。Higuchi博士和Fujiwara博士确定了环糊精包合物，Takagi博士观察了其热行为并讨论了包合现象。Fujiwara博士正在重写传统的X射线结构分析的分子与几个thausand分子量，现在正在开发。

Drs Ashida, Yasuoka, Kai, and Takenaka applied the method of X-ray structure analysis for protien crystal to the molecule with a few thousand molecular weight, established a method to improve the low resolution Fourier map of electron density, showd effectiveness of multi-wavelength anomalous dispersion technique with use of synchrotron radiation, and proved usefulness of the program "MERLOT" for the molecular replacement method. Dr Fujii showed the usefulness of "MERLOT" for X-ray analysis of oligonucleotide crystal and that of "XPLOR" for the molecular dynamics at the refinement of the structure. Dr Ishida suggested that the initial structures obtained from the proton NMR data by ROESY method are useful for the starting model structure of X-ray crystal structure analysis. Dr Okuyama determined a series of the peptide structure containing alpha-aminoisobutyric acid, and discussed factors to determine the type of helix. Dr Hata applied well the protein engineering to heat-stable Enterotoxin and solved the molecular structure. Dr. Iwasaki showed "SHELXS76" was useful for refinement of the disordered structure. Dr. Ohba found usefulness of molecular mechanics calculation to the disordered struture. Dr Ohashi succeeded the crystal structure determination of any stage of the racemic reaction in the crystal. Dr Itai found automatic creation method of drug candidate structure based on receptor structure and developed a program "LEGEND". Dr Osawa wrote a program for the molecular mechanics calculation in crystal, and discussed algorism that in solution. Drs Ito and Ohba tried to solve the structure of commelinin, a pigment from a plant, and got a lot of useful knowledge. Drs Higuchi and Fujiwara determined cyclodextrin inclusion complexes, and Dr Takagi observed its heat behaviour and discussed on the inclusion phenomena. Dr Fujiwara is rewriting the conventional X-ray structure analysis for the molecule with a few thausand molecular weight and is developing now.