PURINE ANALOG ANTIMYCOBACTERIAL DRUG DEVELOPMENT

通过NIAID赞助的结核病抗菌药物获取和协调机制(TAACF)，我们已经确定了许多结构类似于嘌呤碱基和核苷的抗结核分枝杆菌(M.TB)先导化合物。这项赠款提案的目标是了解这些药物在结核分枝杆菌和人类细胞中的新陈代谢，以便确定它们选择性活动的基础。这些研究应能彻底了解结核分枝杆菌嘌呤抢救酶的关键底物特性。由于开发抗肿瘤核苷类似物的相当大的努力，人们对参与嘌呤代谢的人类酶的底物需求知道得很多。然而，人们对结核分枝杆菌嘌呤代谢酶的底物特性知之甚少。建议的研究将弥补这一不足，所获得的信息将有助于基于人类和结核分枝杆菌嘌呤代谢的代谢差异合理设计和开发新的药物。在我们的初步数据中，我们已经确定了结核分枝杆菌和人类嘌呤代谢之间的代谢差异，这可能与结核分枝杆菌对某些腺苷类似物的选择性激活有关。然而，需要进一步的工作才能完全确定这些药物和其他药物的作用机制。为实现这些目标，拟议的具体目标是：(1)腺苷类似物在完整结核分枝杆菌中的代谢和作用机制的表征；(2)从结核分枝杆菌和人类来源中分离和鉴定嘌呤回收酶；(3)设计和合成对结核分枝杆菌具有选择性的腺苷类似物；(4)设计和合成2和6-取代纯度的组合库；(5)在目标4中合成的化合物的初步生化评价；以及(6)抗结核杆菌化合物的评价。结核病的活性和毒性。

Through the NIAID-sponsored Tuberculosis Antimicrobial Acquisition and Coordinating Facility (TAACF), we have identified numerous anti-Mycobacterium tuberculosis (M. tb) lead compounds that are structurally similar to purine bases and nucleosides. The goal of this grant proposal is to understand the metabolism of these agents in M. tb and human cells in order to identify the basis for their selective activity. These studies should lead to a thorough understanding of the substrate characteristics of key M. tb purine salvage enzymes. Much is known about the substrate requirements of human enzymes involved in purine metabolism, because of the considerable effort to develop antitumor nucleoside analogs. However, very little is known about the substrate characteristics of purine metabolizing enzymes in M. tb. The proposed studies should remedy this deficiency, and the information gained will be useful in the rational design and development of new agents based on metabolic differences in purine metabolism between humans and M. tb. In our preliminary data we have identified a metabolic difference between M. tb and human purine metabolism that could be involved in the selective activation in M. tb of certain adenosine analogs. However, further work is necessary to completely characterize the mechanism of action of these and other agents. The proposed specific aims to accomplish these goals are: (1) characterization of the metabolism and mechanism of action of adenosine analogs in intact M. tb; (2) isolation and characterization of purine salvage enzymes from M. tb and human sources; (3) design and synthesis of adenosine analogs selective for M. tb; (4) design and synthesis of a combinatorial library of 2 and 6-substituted purities; (5) preliminary biochemical evaluation of compounds synthesized in aim 4; and (6) evaluation of compounds for anti-M. tb activity and toxicity.