STRUCTURE-FUNCTION STUDIES ON ENZYMES INVOLVED IN THE LYSINE BIOSYNTHETIC PATHWA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 细菌的赖氨酸生物合成是设计新的抗菌剂的一个有吸引力的靶点，因为这一途径对细菌是不可或缺的，而在人类中是不存在的。我们已经对参与细菌病原体和植物赖氨酸生物合成的酶靶标进行了结构研究。其中两种酶的晶体结构已经确定，即流感嗜血杆菌的二氨基opimelate差向异构酶和拟南芥的LL-二氨基opimelate转氨酶。关于这些酶与抑制剂的复合体和突变形式的结构工作仍在继续，以了解用于设计有效抑制剂的催化机理的细节。最近，我们已经从拟南芥中获得了二氨基异构酶的晶体。此外，目前正在对人类病原体衣原体的二氨基苯丙酸氨基转移酶进行结晶试验。我们正在进行合作，对80,000种化合物进行高通量筛选，以便在我们治疗衣原体感染的药物设计工作中为晶体分析寻找潜在的抑制物线索。其他正在进行结晶试验的目标包括引起结核分枝杆菌的二氨基丙二酸二琥珀酸脱琥珀酸酶。为了获得尽可能高的分辨率和质量的衍射数据，以及使用MAD/SAD方法的从头结构溶液，我们需要获得用于大分子结晶学的同步加速器光束线。

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. Bacterial biosynthesis of lysine forms an attractive target for the design of new antimicrobial agents because this pathway is indispensable for bacteria and is absent in humans. We have undertaken structural investigations on enzyme targets involved in the biosynthesis of lysine from bacterial pathogens and plants. Crystal structures of two of these enzymes, namely, diaminopimelate epimerase from Haemophilus influenzae and LL-diaminopimelate aminotransferase from Arabidopsis thaliana have been determined recently. Structural work is continuing on these enzymes in complex with inhibitors and of mutant forms to understand details of the catalytic mechanism for the design of effective inhibitors. Recently, we have obtained crystals of the diaminopimelate epimerase from Arabidopsis. Also, crystallization trials are currently underway on the diaminopimelate aminotransferase from the human pathogen, Chlamydia. We have an ongoing collaboration for high-throughput screening of 80,000 chemical compounds in order to find potential inhibitor leads for crystallographic analysis in our drug design efforts against Chlamydial infections. Other targets undergoing crystallization trials include diaminopimelate desuccinylase from the tuberculosis causing mycobacteria. In order to achieve the best possible resolution and quality of diffraction data, as well as for de novo structure solution using MAD/SAD methods, we require access to the synchrotron beamlines for macromolecular crystallography.