Purine Analog Anti-Mycobacterial Drug Development

描述（由申请人提供）： 通过NIAID赞助的结核病抗微生物收购和协调机构（TAACF），我们已经确定了许多抗结核分枝杆菌的先导化合物，它们在结构上与嘌呤碱基和核苷相似。在目前的资助期（1999年至2003年），我们（1）合成了许多新的化合物，并评估了它们对M。tb，（2）表征了先导化合物之一（2-甲基腺苷）的生化药理学，（3）开始表征M. TB.在新的拨款申请中，我们计划继续这些研究，以进一步了解参与M. tb的选择性抑制剂，并设计合成具有选择性抑制M. TB.由于开发用于治疗癌症和病毒性疾病的核苷类似物的相当大的努力，关于嘌呤补救中涉及的人类酶的底物需求已经知道很多。然而，目前对M. TB.我们已经鉴定了3种在M. tb，可用于开发新的选择性抗-/W。结核病代理商。其中两种酶（腺苷裂解酶和鸟苷激酶）在人类细胞中不表达，我们最近发现第三种酶（腺苷激酶）具有独特的特性，也可用于选择性激活核苷类似物。这些酶的生物化学和遗传学特性应提供有价值的信息，这将是有用的，在合理的设计和开发新的代理人之间的嘌呤代谢的代谢差异的基础上，人类和M。TB. 为实现本项目的资助目标，我们提出的具体目标是：（1）M. tb腺苷切割和鸟苷激酶活性;（2）M. tb腺苷激酶、腺苷裂解和鸟苷激酶活性;（3）具有强效和选择性抗M. tb活性;（4）设计和合成具有抗M. TB.

DESCRIPTION (provided by applicant): Through the NIAID-sponsored Tuberculosis Anti-microbial Acquisition and Coordinating Facility (TAACF), we have identified numerous anti-Mycobacterium tuberculosis lead compounds, which are structurally similar to purine bases and nucleosides. In the current grant period (1999 to 2003) we have (1) synthesized many new compounds and evaluated them for activity against M. tb, (2) characterized the biochemical pharmacology of one of the lead compounds (2-methyladenosine), and (3) begun the characterization of the enzymes involved in purine salvage in M. tb. In the new grant proposal we plan to continue these studies to further our understanding of the enzymes involved in the purine salvage pathway in M. tb and to design and synthesize new agents with selective activity against M. tb. Much is known about the substrate requirements of human enzymes involved in purine salvage, because of the considerable effort to develop nucleoside analogs for the treatment of cancer and viral diseases. However, very little is currently known about the substrate characteristics of these enzymes in M. tb. We have identified 3 purine salvage enzymes that are expressed in M. tb that could be exploited in the development of new selective anti-/W. tb agents. Two of these enzymes (adenosine cleavage and guanosine kinase) are not expressed in human cells and we have recently shown that the third enzyme (adenosine kinase) has unique characteristics that could also be used for selective activation of nucleoside analogs. The biochemical and genetic characterization of these enzymes should provide valuable information that will be useful in the rational design and development of new agents based on metabolic differences in purine metabolism between humans and M. tb. The proposed specific aims to accomplish the goals of this grant proposal are: (1) identification, cloning, expression, and purification of M. tb adenosine cleavage and guanosine kinase activities; (2) biochemical characterization of M. tb adenosine kinase, adenosine cleavage, and guanosine kinase activities; (3) metabolic studies with new agents that have potent and selective anti-M. tb activity; and (4) design and synthesis of purine and purine nucleoside analogs with selective activity against M. tb.