ASSEMBLY OF A MEMBRANE-BOUND MULTI-ENZYME COMPLEX

大肠杆菌中的甲酸-硝酸还原酶途径正在被使用 作为一个实验系统来研究一个有组织的， 膜结合的多酶复合物。 甲酸-硝酸还原酶途径 在大肠大肠杆菌是一个电子传递系统， 膜，从而以蛋白质梯度的形式产生能量 在电子从甲酸盐转移到硝酸盐的过程中。我们的长期目标 是为了确定该成分生物合成的分子机制 蛋白质，它们插入膜，它们组装成 多亚基复合物和非蛋白辅因子的掺入 将组分转化为功能性酶复合物。 我们的直接具体 目标集中在这一途径的酶复合物之一，硝酸盐 还原酶;我们建议利用生物化学，遗传和重组DNA 技术来确定（1）nar操纵子的结构和 具体成分参与其调节，（2）NAR的产品 操纵子，包括酶亚基和其他可能的调节 （3）特定亚基在细胞间相互作用中的作用。 酶与膜在体外和体内。 较长期研究 将启动对亚基上特定蛋白质结构域的作用的研究 相互作用并插入膜中。

The formate-nitrate reductase pathway in Escherichia coli is being employed as an experimental system for studying the biogenesis of an organized, membrane-bound multienzyme complex. The formate-nitrate reductase pathway in E. coli is an electron transport system which is organized in the cell membrane so that energy, in the form of a protein gradient, is generated during transfer of electrons from formate to nitrate. Our long range goal is to define the molecular mechanisms in the biosynthesis of the component proteins, their insertion into the membrane, their assembly into multisubunit complexes and the incorporation of non-protein cofactor components into the functional enzyme complexes. Our immediate specific aims are focused on one of the enzyme complexes of this pathway, nitrate reductase; We propose to utilize biochemical, genetic and recombinant DNA techniques to determine (1) the structure of the nar operon and the specific component involved in its regulation, (2) the products of the nar operon, including the enzyme subunits and other possible regulatory components, (3) the role of specific subunits in the interaction of the enzyme with the membrane both in vitro and in vivo. Longer range studies will initiate studies on the role of specific protein domains on subunit interactions and insertion into the membrane.