Tethered Domains As Regulatory Elements

描述（由申请人提供）：我们的工作有助于发现ACT结构域，这是一种由小分子调节的蛋白质调节结构域，并产生了典型的ACT结构域的结构。这项研究的目标是继续研究ACT结构域对蛋白质的调节机制并将其与本实验室的长期目标联系起来即确定构象调节控制机制中结构和功能之间的关系，最终将其与这些酶和类似系统介导的生理和病理生理联系起来，并最终充分理解蛋白质的构象介导过程以便能够将基本原理应用于更复杂的系统。具体目的是：1)阐明大肠杆菌和结核分枝杆菌D-3-磷酸甘油酸脱氢酶（PGDN）中ACT结构域的作用机制；2)阐明结核分枝杆菌PGDH中可能与ACT结构域结合的新结构域和小分子结合位点的功能；3)确定人类PGDH的结构和功能。4)筛选结核分枝杆菌PGDH的配体结合位点，开发抑制剂，用于评估PGDH在结核分枝杆菌活性、适应性和持续性代谢中的作用，并可能最终用于治疗多重耐药结核病。这项工作的相关性是双重的。首先，ACT结构域是一个新发现的结构域，在许多蛋白质的调控中起作用。确定其作用机制及其在蛋白质中的普遍性将有助于我们了解蛋白质在生理和疾病中的调控作用，并为基因替代治疗中的蛋白质调控提供潜在的新武器。其次，耐多药结核病是一个日益严重的问题，影响到世界上很大一部分人口。我们观察到结核分枝杆菌的PGDH被l -丝氨酸抑制，而人类的PGDH不受l -丝氨酸的抑制，这可能为结核病治疗药物的开发提供新的重点。

DESCRIPTION (provided by applicant): Our work has contributed to the discovery of the ACT domain, a protein regulatory domain modulated by small molecules, and has produced the structure of the archetypical ACT domain. The goal of this research is to continue our investigation into the mechanism of regulation of proteins by the ACT domain and to relate this to the long term goals of this laboratory which are to determine the relationship between structure and function in conformationally regulated control mechanisms, to eventually relate that to the physiology and pathophysiology mediated by these enzymes and by analogous systems, and to eventually understand conformational mediated processes in proteins well enough to be able to apply basic principles to more complex systems. The specific aims will 1) elucidate the mechanism of the ACT domain in D-3- phosphoglycerate dehydrogenase (PGDN) from E. coli and M. tuberculosis, 2) elucidate the function of a new structural domain and small molecule binding site found in M. tuberculosis PGDH that may function in conjunction with the ACT domain, 3) determine the structure and function of human PGDH, and 4) screen the ligand binding sites of M. tuberculosis PGDH for the development of inhibitors that can be used to assess the role of PGDH in the metabolism of M. tuberculosis during its active, adaptive and persistent phases and that may eventually be used for the treatment of multi-drug resistant tuberculosis. The relevance of this work is 2-fold. First, the ACT domain is a newly recognized structural domain that functions in the regulation of many proteins. Determining its mechanism and the universality of its action among proteins will contribute to our understanding of protein regulation in physiology and disease as well as provide a potential new weapon for protein regulation in gene replacement therapy. Secondly, multi-drug resistant tuberculosis is a growing problem that impacts a large percentage of the world's population. Our observations that PGDH from M. tuberculosis is inhibited by L-serine and that PGDH from humans is not, may provide a new focus in drug development for treatment of tuberculosis.