Catalytic and Regulatory Properties of Hybrid ATCases Formefrom Native and Genetically Reconstructed Subunits of Divergent Bacteria

天冬氨酸转氨甲酰酶（ATCases） 微生物，特别是肠细菌， 在可比高等教育中组织起来足够相似 结构域并组装成类似的四元聚集体。 然而，它们的催化作用不同， 性质和变构反应。 各种基因间 已经从细菌顺反子进行了融合， 仓鼠cDNA克隆和它们的表征正在进行中。 催化和调节链的序列已经被 测定 这些将进行比较，希望 足够数量的序列：函数比较将 允许推断关键结构/功能 关系。 将进行位点特异性诱变 目的是阐明每一部分的功能， 催化和调节多肽。 单克隆抗体 将被用来比较酶的表面结构， 不同的物种 与X射线合作 晶体学家应该提供明确的结构 有趣的突变改变蛋白质的信息。 这是一个很好的模型系统， 怀尔德博士过去的工作使他成为唯一有资格 提出了

The Aspartate transcarbamoylases (ATCases) of divergent organisms, and in particular of enterobacteria, are sufficiently similar to organize in comparable tertiary domains and to assemble in similar quaternary aggregates. Nevertheless, they differ from each other by their catalytic properties and allosteric responses. Various intergenic fusions have been carried out from bacterial cistrons and hamster cDNA clones and their characterization is underway. The sequences of catalytic and regulatory chains have been determined. These will be compared in the hope that a sufficient number of sequence: function comparisons will permit deduction of critical structure/function relationships. Site specific mutagenesis will be performed aimed at elucidating the function of each segment of these catalytic and regulatory polypeptides. Monoclonal antibodies will be used to compare surface structures of the enzyme from different species. Collaboration with x-ray crystallographers should provide definitive structural information of interesting mutationally altered proteins. This is an excellent model system for such studies and Dr. Wild's past work makes him uniquely qualified for what is proposed.