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81.
Predictive modelling of the 3-D structure of interleukin-13 总被引:1,自引:0,他引:1
Bamborough Paul; Duncan David; Richards W.Graham 《Protein engineering, design & selection : PEDS》1994,7(9):1077-1082
Several atomic structures are now available for the family ofhelical cytokines, which includes growth hormone as well asmany of the interleukins. Using structural information fromfive members of this family, two alternative models of interleukin(IL)-13 are proposed. IL-13 has biological properties similarto those of IL-4 and, like the other interleukins, is a potentiallyimportant pharmaceutical target. The model of IL-13 is discussedand compared with the known interleukin structures. 相似文献
82.
磺化竹红菌素对蛋白质荧光猝灭机理的研究 总被引:1,自引:0,他引:1
本文详细研究了磺化竹红菌素对多种蛋白质在溶液状态下的荧光猝灭过程。结果表明,磺化竹红菌素对多种蛋白质荧光猝灭服从Sten-Volmer曲线。实验观察了温度、粘度、pH值和盐酸胍对荧光猝灭过程的影响。由于磺化竹红菌素是一两性分子,对于不同蛋白具有不同猝灭过程;磺化竹红菌素对蛋白质的荧光猝灭常数Kq在10^13mol/L.s^-1左右,这说明,磺化竹红菌素是一种比其它蛋白质荧光猝灭剂更加有效的荧光猝灭 相似文献
83.
大豆蛋白分离工艺研究 总被引:2,自引:0,他引:2
阐述了大豆蛋白质的分离原理,分析了运用“碱提酸沉”分离法提取大豆蛋白质过程中,豆粕的粉碎方式、浸提温度、浸提时间、浸提液的pH值以及离心工艺对提取效果的影响,为大豆蛋白/聚丙烯腈纤维的工业化生产提供了依据。 相似文献
84.
Altschuh Daniele; Tessier Daniel C.; Vernet Thierry 《Protein engineering, design & selection : PEDS》1994,7(6):769-776
The two main catalytic residues Cys25 and Hisl59 of the monomericcysteine protease papain are located on different walls of acleft formed by two domains. This topology suggests a possiblerelationship between relative domain organization and catalyticmechanism. The effect on enzymatic parameters of structuralmodifications at various locations of the twodomain interfaceof papain was examined by individual or double replacementsby Ala of pairs of interacting residues. Most modificationshad no effect on enzyme activity. However, the enzyme's substrateturnover (kcat) decreased following simultaneous alterationof the two most conserved residues, forming an apolar contactlocated 15 Å away from the active site. The pH activityprofile of the double mutant was unchanged, indicating a conservedionization state of the active site thiolate-imidazolium ionpair. This state is strongly dependent on the distance separatingthe two residues, thus suggesting that the active site geometryhas not been significantly altered. Efficient enzymatic activityin papain requires more than a correct active site geometryand is influenced by domain packing properties in a region remotefrom the active site. 相似文献
85.
蛋白质分子链的超声速孤立子 总被引:3,自引:0,他引:3
在Davydov简谐蛋白质分子链模型的基础上,进行合理的连续近似处理,得到了超声速和亚声速孤立子解,并求得孤立子能量. 相似文献
86.
Whey is an undurable product. treated very often as a waste which pollutes the natural environment. Whey which is a valuable source of protein, lactose, vitamins and mineral salts should be utilized completely. The present paper is a proposal of whey drying on porous carriers. It is proved experimentally that the proposed drying method guarantees good product quality. 相似文献
87.
88.
89.
CDC15, an essential cell cycle gene in Saccharomyces cerevisiae, encodes a protein kinase domain 总被引:17,自引:0,他引:17
The cell division cycle gene CDC15 is essential for the late nuclear division in the yeast Saccharomyces cerevisiae. The amino acid sequence of the 974 amino acids/110 kDa CDC15 gene product, as deduced from the nucleotide sequence, includes an aminoterminal protein kinase domain which contains a primary sequence mosaic showing patterns specific for protein serine/threonine kinases besides those for protein tyrosine kinases. Many protein kinases non-essential for growth are known. CDC15 represents an essential protein kinase like CDC7 and CDC28. A carboxyterminal deletion of 32 amino acids renders the protein inactive. 相似文献
90.
Tadeusz Aniszewski 《Journal of the science of food and agriculture》1993,61(4):409-421
Abstract : An alkaloid-poor line of Washington lupin (Lupinus polyphyllus Lindl var SF/TA) was developed in an experiment started in 1982. The nutritive quality (alkaloid content, protein and amino acids, fat and fatty acids. macro- and micronutrients, fibre, sugars) yields, and seed quality of this line were studied. The results show that the total alkaloid content was low and varied in different seeds from 226 μg g?1 to 366 μg g?1 of dry matter. The main alkaloid was lupanine, but 16 other alkaloids (including sparteine and gramine) were also present. The var SF/TA cannot yet be used for human nutrition without processing although it would be a valuable protein crop. The results confirm that seeds which look different also vary in chemical composition. 相似文献