STRUCTURAL STUDIES OF AIDS-RELATED ENZYMES AND OTHER PATHOGENIC TARGETS

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 霍普特曼-伍德沃德医学研究所(HWI)的科迪实验室有一个多方面的研究计划，重点是了解位点特定残留物在设计病原体选择性抑制剂中的作用，例如肺孢子虫(Pc)，这是免疫功能低下患者，特别是艾滋病患者机会性感染和死亡的主要原因。肺孢子虫肺炎(PCP)是免疫功能低下患者中最常见和最严重的机会性感染之一。在这项提案中，我们要求波束时间发展生物结构研究的互补领域。最近的研究表明，随着时间的推移，肺孢子虫的靶标酶二氢叶酸还原酶(DHFR)和二氢蝶呤酸合酶(DHPS)会积累突变，可能会导致耐药性。该项目的一个主要目标是表征pjDHFR和pjDHPS及其变异体，以设计具有治疗PCP潜力的有效抑制剂。DHFR酶的定点突变研究正在进行中，以确定特定残基在调节DHFR抑制剂效力和增加对pjDHFR耐药性方面的作用，正如在艾滋病患者分离株中观察到的那样。人DHFR抑制剂复合体的结构正在研究中，以比较它们与肺孢子虫DHFR酶的结构。我们需要使用同步辐射来确定这些抑制剂复合体的高分辨率细节。在另一项合作研究中(瓦格纳大学明尼苏达州)，大肠杆菌DHFR二聚复合体正在被研究以设计新的纳米管组件。需要结构数据来验证二聚化组装，并确定二聚体界面的突变如何调制纳米管组装。由于这些晶体往往较小且衍射率较低，因此需要同步加速器的时间。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The Cody lab at the Hauptman-Woodward Medical Research Institute (HWI) has a multi-faceted research program that focuses on understanding the role of site specific residues in the design of selective inhibitors of pathogens such as Pneumocystis (Pc), a major cause of opportunistic infection and mortality in immunocompromised patients, particularly those with AIDS. Pneumocystis jirovecii (pj) is the causative agent of Pneumocystis pneumonia (PcP), one of the most frequent and severe opportunistic infections in immunocompromised patients. In this proposal, we request beamtime to develop complementary areas of biological structural research. Recent studies show that mutations accumulate over time in the target enzymes, dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) from Pneumocystis, potentially giving rise to drug resistance. A major goal of this project is to characterize pjDHFR and pjDHPS and their variants in order to design effective inhibitors that have potential as therapeutic agents for the treatment of PcP. Site-directed mutagenesis studies on DHFR enzymes are under investigation to determine the role of specific residues in modulating DHFR inhibitor potency and in conferring drug-resistance to pjDHFR as observed in AIDS patient isolates. Structures of human DHFR inhibitor complexes are under investigation to compare their structures with those of the Pneumocystis DHFR enzymes. We require the use of synchrotron radiation to determine high-resolution details of these inhibitor complexes. In another collaborative study (Wagner, Univ. Minnesota), E. coli DHFR dimerization complexes are being investigated to design novel nanotube assemblies. Structural data are needed to validate dimerization assembly and to determine how mutations at the dimer interface modulate nanotube assembly. Sychrotron time is needed as these crystals tend to be small and diffract modestly.