LEISHMANIA MEXICANA ALDOLASE INHIBITION STUDIES

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。由于寄生虫病，第三世界国家正处于危机之中。一种主要疾病是由锥虫引起的，锥虫是一种单细胞生物，完全依赖糖酵解来满足其新陈代谢能量需求。我们的方法是使用针对糖酵解酶的抑制剂来阻止糖酵解。酶的靶标是果糖-1，6-二磷酸缩醛酶，因为它在糖酵解途径中处于关键地位。我们的模型酶是墨西哥利什曼原虫醛缩酶，它的结构已经被解决。它的催化位置不同于一个关键的丙氨酸残基，它取代了哺乳动物醛缩酶中观察到的甘氨酸残基。对哺乳动物酶的研究将假定的丙氨酸放在底物(1，6-二磷酸果糖)磷酸结合部位附近，暗示寄生虫和哺乳动物醛缩酶的结合差异。我们项目的目标是解决墨西哥利什曼原虫醛缩酶-配体复合体的结构，并将这些复合体的结构与哺乳动物醛缩酶结合的底物/抑制物进行比较。使用ADSC 3x3探测器在x29进行数据采集使我们能够以最高分辨率采集数据，否则由于我们晶体中的单位晶胞尺寸较长，这是不可能的。我们建议收集几个反应络合物的高分辨率数据，从这些数据中设计基于机理的先导化合物，这些化合物将通过迭代几轮晶体结构确定进行优化。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Third world countries are in a crisis situation because of parasitic diseases. A major disease is caused by trypanosomatids, unicellular organisms that rely solely on glycolysis to meet their metabolic energy demands. Our approach is to use inhibitors directed against glycolytic enzymes to stop glycolysis. The enzyme target is fructose-1,6-biphosphate aldolase because of its key-position in the glycolysis pathway. Our model enzyme is Leishmania mexicana aldolase whose structure is already solved. Its catalytic site differs by a critical alanine residue that replaces a glycine residue observed in mammalian aldolases. Studies on the mammalian enzyme places the putative alanine near one of the substrate (fructose-1,6-bisphosphate) phosphate binding sites alluding to binding differences between parasite and mammalian aldolases. The goal of our project is to solve the structure of Leishmania mexicana aldolase-ligand complexes and to compare the structure of these complexes with substrate/inhibitors bound in mammalian aldolases. Data collection at X29 using the ADSC 3x3 detector has allowed us to collect data to maximum resolution otherwise not possible because of a long unit cell dimension in our crystals. We propose to collect high resolution data on several reaction complexes from which to design mechanism based lead compounds that will be optimized through iterative rounds of crystal structure determination.