Targeting isoprenoid biosynthesis in Plasmodium falciparum

靶向恶性疟原虫中的类异戊二烯生物合成

• 批准号: 7684818
• 负责人: Audrey Ragan Odom John
• 金额: $ 11.13万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-15 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7684818
• 关键词: 1-deoxy-2-pentulose; Abbreviations; Anabolism; Antimalarials; Antiparasitic Agents; Area; Biochemical; Biochemical Genetics; Biological; Biological Assay; Biology; Cell Respiration; Cell physiology; Characteristics; Chemicals; Childhood; Communicable Diseases; Complement; Development; Drug Delivery Systems; Drug resistance; Electron Transport; Enzymes; Evaluation; Future; Generations; Genetic; Goals; Green Fluorescent Proteins; Growth; Growth and Development function; Human; Laser Scanning Confocal Microscopy; Location; Malaria; Membrane; Metabolic Pathway; Methods; Mission; Molecular and Cellular Biology; National Institute of Allergy and Infectious Disease; Organism; Parasites; Pathogenesis; Pathway interactions; Pigments; Plasmodium; Plasmodium falciparum; Program Development; Public Health; Quinones; Recombinants; Reproduction; Research; Research Design; Research Personnel; Role; Signal Transduction; Signaling Molecule; Sterols; Therapeutic; Training Programs; Transgenic Organisms; career; deoxyxylulose phosphate; drug development; enzyme pathway; fosmidomycin; high throughput screening; improved; in vitro Assay; in vitro activity; inhibitor/antagonist; inorganic phosphate; insight; interest; isoprenoid; mevalonate; pathogen; programs; research study; small molecule

DESCRIPTION (provided by applicant): Relevance to NIAID mission: This application describes a 5-year training program for the development of an academic career in Pediatric Infectious Diseases, with a goal of independently directing research into parasite biology, pathogenesis, and therapy. Research design and methods: New antimalarial agents are urgently needed due to the spread of drug resistance in the pathogen Plasmodium falciparum. Understanding the fundamental biology of P. falciparum is key to these drug development efforts. An important metabolic pathway in all organisms is the biosynthesis of isoprenoid molecules, fundamental building blocks for diverse cellular compounds vital for cellular respiration, membrane structure, and signaling. We hypothesize that this pathway is also essential for the normal development and reproduction of Plasmodium falciparum. In malaria species, isoprenoids are made via the non-mevalonate (DXP) pathway. The parasite DXP pathway is biochemically distinct from the mevalonate pathway in humans, and evidence suggests this pathway is required for parasite survival. Research will focus on two enzymes of this pathway, deoxyxylulose phosphate reductoisomerase (DXR) and methylerythritol cyclodiphosphate synthase (IspF). To study the biological and biochemical characteristics of DXR and IspF, we propose a dual-pronged biochemical and genetic approach. The specific aims include the following: (1) Heterologous expression of DXR and IspF, development of in vitro assays suitable for high-throughput screening, and biochemical characterization of both enzymes; (2) Localization of DXR and IspF within the parasite by development of transgenic strains of P. falciparum that express GFP-fusions of DXR and IspF; (3) Generation of DXR and IspF disruption strains of P. falciparum, if possible, and detailed analysis of the phenotypic effects of inhibition of isoprenoid biosynthesis in both parasite disruption strains and strains treated with a small-molecule inhibitor of DXR, fosmidomycin. Relevance to public health: These experiments explore the basic biology of a fundamental metabolic pathway, isoprenoid biosynthesis, of Plasmodium falciparum. Isoprenoid compounds, which include quinones, photosynthetic pigments, and sterols, are vital to cellular function. This area of research is expected to provide insights into parasite pathogenesis, and ultimately therapeutics.

描述（由申请人提供）：与NIAID任务相关：本申请描述了一项为期5年的培训计划，以开发儿科传染病的学术生涯，其目的是将研究独立地引导到寄生虫生物学，发病机理和治疗中。研究设计和方法：由于耐药性在恶性疟原虫中的耐药性扩散，因此迫切需要新的抗疟药。了解恶性疟原虫的基本生物学是这些药物开发工作的关键。在所有生物体中，一个重要的代谢途径是类异型分子的生物合成，用于各种细胞化合物的基本构件对于细胞呼吸，膜结构和信号传导至关重要。我们假设该途径对于恶性疟原虫的正常发育和繁殖也至关重要。在疟疾物种中，类异on-是通过非甲酸盐（DXP）途径制成的。寄生虫DXP途径在生物化学上与人类的甲谷酸盐途径不同，证据表明寄生虫生存需要这种途径。研究将侧重于该途径的两种酶，氯糖糖还原异构酶（DXR）和甲基雄性环醇环磷酸合酶（ISPF）。为了研究DXR和ISPF的生物学和生化特征，我们提出了一种双管生化和遗传方法。具体目的包括：（1）DXR和ISPF的异源表达，适合高通量筛查的体外测定的开发以及两种酶的生化表征； （2）通过表达DXR和ISPF的GFP - 伴侣的转基因菌株的发展，将DXR和ISPF定位在寄生虫中； （3）如果可能的话，DXR和ISPF破坏性菌株的产生，以及对寄生虫干扰菌株中异急动物生物合成抑制的表型作用的详细分析，以及用DXR小分子抑制剂的DXR抑制剂治疗的dxR菌株，fosmidomycin，fosmidomycin。与公共卫生的相关性：这些实验探讨了恶性疟原虫的基本代谢途径，类异型生物合成的基本生物学。类异型化合物，包括喹酮，光合色素和固醇，对细胞功能至关重要。预计这一领域将提供有关寄生虫发病机理和最终治疗剂的见解。