STRUCT & FUNCT OF MUTANT VERSIONS OF ALKALINE PHOSPHATASE FROM ECOLI

该项目的目标是获得更深入的了解 蛋白质结构与功能的关系 碱性磷酸酶作为模型系统。 这种酶的功能 是催化磷酸酯的非特异性水解， 缺乏这种酶的活性会导致致命的遗传性 低磷酸酶症 哺乳动物的碱性磷酸酶是 与相应的细菌酶密切相关，并且该酶 已经成为研究所有 碱性磷酸酶 在PSC的Y-MP C90上的额外时间是 是为了继续这个项目。 这涉及 使用XPLOR程序来细化X射线晶体学数据， 数据已经可用的酶的突变形式，以及 至少还有另外四个国家的数据将很快收集。 我们 还将使用XPLOR和CHARMM进行分子动力学 对酶的突变体进行计算， 了解其不寻常的属性。 本地电脑设施包括 无法在合理时间内进行这些计算。 然后，将在诱发的功能变化之间进行相关性分析。 通过氨基酸取代和三维结构， 突变酶 这项工作将不仅是重要的 了解这个特殊的系统，但更重要的是， 阐述了酶催化的一般概念， 蛋白质中的金属，并提供了一个分子解释， 基因间互补

The goals of this project are to acquire a deeper understanding of the relationship between protein structure and function by using alkaline phosphatase as a model system. The function of this enzyme is to catalyze the nonspecific hydrolysis of phosphate esters, and the lack of the activity of this enzyme results in the fatal hereditary disease hypophosphatasia. Alkaline phosphatase from mammals is closely related to the corresponding bacterial enzyme, and the enzyme from Escherichia coli has become the model for the study of all alkaline phosphatases. Additional time on the Y-MP C90 at PSC is being requested in order to carry on with this project. This involves using the program XPLOR to refine the x-ray crystallography data on mutant versions of the enzyme for which data is already available, and at least four others for which data will be collected shortly. We will also use of XPLOR and CHARMM to carry out molecular dynamics calculations on mutant versions of the enzyme in order to help understand their unusual properties. Local computer facilities are not capable of carrying out these calculations in reasonable times. Correlations will then be made between the functional changes induced by the amino acid substitution and the three-dimensional structure of the mutant enzymes. This work will not only be important for the understanding of this particular system, but more importantly for formulating general concepts about enzyme catalysis, and the function of metals in proteins, and providing a molecular explanation for intergenic complementation.