STRUCTURAL STUDIES OF PROTEIN RECOGNITION

蛋白质之间的识别和随后的相互作用 而其他分子在许多基础上扮演着重要的角色 生物过程。这个项目的总体目标是 了解蛋白质如何识别其他蛋白质的分子基础 分子，包括小分子配体以及 大分子，如核酸和蛋白质，使用单一 晶体x射线衍射研究。这项工作的基本原理 蛋白质可能具有某些特定的折叠特性 底物结合功能的“基序”。具体来说，我们 提出结晶化和确定三维 几种蛋白质系统的结构。这些包括1)蛋白质 与DNA相互作用的基因：E.ColiHu蛋白、IKE和Fd基因5 蛋白质和大肠杆菌Rep酶及其与DNA的络合物 2)氨基酰基tRNA合成酶片段和 它们与tRNA的络合物；3)抗阿司匹林的Fab片段 免疫球蛋白；4)具有DNA结合作用的合成肽 活动。 我们希望用和不用它们的方法来结晶这些蛋白质。 各自的底物，这样我们就可以可视化的结构 形成复合体前后的蛋白质。详细 对蛋白质结构的了解将使我们能够评估 蛋白质分子的构象变化及其预测 改变现有蛋白质或设计新蛋白质的方法 各种功能。 本项目中拟议的研究涉及与 该项目的其他主要调查人员。通过 结合重组DNA方法学的知识， 单抗技术、核苷酸和多肽 计划项目中的化学和X射线结晶学， 我们希望最终实现以下长期目标 了解的结构、相互作用和功能 蛋白质和设计改进的或所需的新蛋白质 功能。

The recognition and subsequent interactions between a protein and other molecules play essential roles in many fundamental biological processes. The overall objective of this project is to understand the molecular basis of how proteins recognize other molecules, including small molecule ligands as well as macromolecules such as nucleic acids and proteins, using single crystal x-ray diffraction studies. The rationale of the work here is that proteins may possess certain characteristic folding "motifs" for their substrate binding functions. Specifically, we propose to crystallize and determine the three dimensional structure of several proteins systems. These include 1) proteins that interact with DNA: E. coli Hu protein, Ike and fd gene 5 protein and E. coli Rep enzyme and their complexes with DNA oligonucleotides; 2) Aminoacyl tRNA synthetase fragments and their complexes with tRNA; 3) Fab fragments of antiarsonate immunoglobulins; 4) Synthetic peptides possessing DNA binding activity. We hope to crystallize these proteins with and without their respective substrates so that we can visualize the structure of the protein before and after complex formation. Detailed knowledge of the protein structure will allow us to assess the conformational changes in the protein molecule and to predict ways of altering existing proteins or designing new proteins of various functions. The proposed studies in this project involve collaboration with other principal investigators in the program project. By combining the knowledge of recombinant DNA methodology, monoclonal antibody technology, nucleotide and peptide chemistry and x-ray crystallography within the program project, we hope ultimately to achieve the long range goal of understanding the structure, interactions and function of proteins and of designing new proteins of improved or desired functions.