Molecular manipulation of oxygen binding proteins and new development of precise structure-function studies on them

从目前的项目中得到了以下结果。1.人工突变对血红蛋白（Hb）氧亲和性的控制（Imai）， 2.以金属取代杂化Hbs作为脱氧和氧血红素模型的Mg^<2+>和Cr^<3+>-卟啉的微观氧平衡常数的测定（Morimoto）， 3。通过模块交换和分子内二硫键分析肌红蛋白（Mb）的配体结合动力学（Morishima）， 4。5.利用紫外共振拉曼光谱检测HbNO (+IHP) t态和脱氧hb t态在α 1- β 2接触点的结构差异（Kitagawa）；利用突变体和化学修饰的Hbs （Nagai）鉴定287 nm处CD负带的氨基酸残基作为t态标记；7.对Mb晶体（Go）的x射线衍射数据应用精密正态模式分析获得的中子衍射数据和波动的温度依赖性数据的比较；血红素在Mb折叠过程中的作用通过使用各种光学探针的停流法研究（Kihara）， 9。血红蛋白接触的改变对Mb功能的影响很小，而将氮原子引入卟啉的介观位置会对Mb功能产生巨大影响（Neya）， 10。环节动物Hb的巨大尺寸是通过连接链和确定连接链在Hb分子中的位置的凝集素样糖粘附来维持的（Gotoh）， 11。来自穆斯林壳的Mb与吲哚胺2,3-双加氧酶高度同源，表明前者是从后者进化而来的（Suzuki）， 12。铈的自氧化伴随着二聚体到单体的转化（Shikama）和13。优化了人胎儿血红蛋白的氧平衡曲线，以在低氧压力环境下实现高效的氧运输，而优化了人成人血红蛋白的氧平衡曲线，以最大限度地利用玻尔效应（Kobayashi）。少

From the present project the following results were obtained. 1.Control of oxygen affinity of hemoglobin (Hb) with cooperativity preserved by means of artificial mutations (Imai), 2.determination of microscopic oxygen equilibrium constants and test of Mg^<2+> and Cr^<3+>-porphyrins as the model for deoxy-and oxyhemes using metal-substituted hybrid Hbs (Morimoto), 3.constitution of novel globins by module exchanges and analysis of ligand binding kinetics of myoglobin (Mb) with intramolecular disulfide bond (Morishima), 4.identification of the fifth axial ligand for the oxygen sonsor protein FixL of root nodule bacterium (Iizuka), 5.detection of structural differences at the alpha1-beta2 contacts between HbNO (+IHP) T-state and deoxyHb T-state by means of ultraviolet resonance Raman spectroscopy (Kitagawa), 6.identification of the amino acid residues contributing to the negative CD band at 287 nm as a T-state marker using mutant and chemically modified Hbs (Nagai), 7.comparison between n … More eutron diffraction data for Mb crystal and temperature-dependence data of fluctuation obtained by applying the precision normal mode analysis to X-ray diffraction data for Mb crystal (Go), 8.the role of heme group in the folding process of Mb studied by stopped-flow method using various optical probes (Kihara), 9.changes in heme-globin contacts cause only small effects on Mb functions whereas introduction of nitrogen atoms into the meso position of porphyrin causes drastic effects on Mb functions (Neya), 10.the giant size of the annelid Hb is maintained by lectin-like sugar adhesion via linker chains and determination of the location of the linker chains in the Hb molecule (Gotoh), 11.Mb from turban shell shows high homologous with indoleamine 2,3-dioxygenase, suggesting that the former evolved from the latter (Suzuki), 12.the autooxidation of Cerithidea Mb is accompanied with dimer-to-monomer conversion (Shikama) and 13.the oxygen equilibrium curve for human fetal Hb is optimized to attain highly efficient oxygen transport under low oxygen pressure environments while that for human adult Hb is optimized to utilize the Bohr effect at maximum (Kobayashi). Less