Genetic dissection of parasite metabolism

寄生虫代谢的基因剖析

基本信息

批准号：
8232138
负责人：
BORIS STRIEPEN
金额：
$ 33.48万
依托单位：
UNIVERSITY OF GEORGIA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-03-15 至 2015-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8232138
关键词：
AIDS-Related Opportunistic Infections Ablation Acetates Acquired Immunodeficiency Syndrome Acyl Carrier Protein Adverse effects Affect Anabolism Antiparasitic Agents Apicomplexa Bacterial Typing Benign Biochemical Bioinformatics Biology Bioterrorism Blindness Cataloging Catalogs Cells Centers for Disease Control and Prevention (U.S.)Chloroplasts Chronic Complex Complication Cryptosporidiosis Cryptosporidium Disease Disease Management Disease Outbreaks Dissection Drug Delivery Systems Engineering Enzymes Epitopes Essential Fatty Acids Eye Infections Fatty Acids General Practitioners Genes Genetic Growth Growth and Development function HIV Hematologic Neoplasms Horizontal Gene Transfer Human Individual Infection Inherited Intercept Intervention Lead Life Life Cycle Stages Life Style Lipids Malaria Measures Metabolic Metabolism Modeling Modification Multi-Drug Resistance Nature Organelles Parasites Pathway interactions Pharmaceutical Chemistry Pharmaceutical Preparations Pharmacotherapy Plasmodium malariae Population Public Health Radiolabeled Recrudescences Regulation Relative (related person)Rest Role Route Staging System Testing Time Toxoplasma Toxoplasma gondii Toxoplasmosis Transplant Recipients Vaccines Virulent antimicrobial drug comparative genomics drug development effective therapy enzyme pathway fascinate fatty acid metabolism flexibility genome sequencing human disease immunosuppressed in vivo lipid metabolism metabolomics mutant novel novel strategies parasite genome pathogen positional cloning public health relevance radiotracer reconstruction tool transmission process uptake waterborne

项目摘要

DESCRIPTION (provided by applicant): This proposal outlines a comprehensive plan to genetically dissect the fatty acid metabolism of the human pathogen Toxoplasma gondii. T. gondii infection is widespread in the U.S. (22% of the population is chronically infected) and while usually benign can cause life-threatening disease in immunosuppressed individuals (e.g. those with HIV-AIDS, transplant recipients, or hematological malignancies). Congenital transmission of T. gondii is also a major public health concern. Highly virulent parasite strains have been recently identified as the cause of severe and recurring eye infections that ultimately lead to blindness. T. gondii also has the potential to cause significant waterborne outbreaks and has been listed by the CDC as a potential bioterrorism pathogen (appendix B). The currently available treatment has frequent and significant adverse effects and shows no efficacy in chronic infection, thus allowing for recrudescence of the active infection. Thus, new drugs are urgently needed. The discovery of a chloroplast-like organelle in apicomplexan parasites provides several promising parasite-specific target pathways for drug development. Among these pathways is a bacterial type II fatty acid synthesis pathway, and enzymes in this pathway have been the subject of intensive medicinal chemistry efforts to develop drugs against malaria and toxoplasmosis. However, what the precise function of this pathway for T. gondii and related apicomplexan parasites is remains unclear. Furthermore, the parasite genome encodes additional enzyme systems that might supply fatty acids either by synthesis or salvage from the host cell. A detailed understanding of the function and relative importance of these pathways is needed to guide the drug development effort to the most promising targets. In this project we will use genetics and metabolomics to dissect the complex interaction of three individual pathways. Using a novel and highly efficient approach to engineer conditional T. gondii mutants we will rigorously test the importance and function of each individual pathway in vivo. We will determine the impact of the loss of specific pathways on the parasite fatty acid and lipid composition using unbiased metabolomic profiling. To define the interactions between individual pathways and between the parasite and its host cell we conduct metabolic flux studies using stable epitope tracing. Overall we expect the outlined studies to produce a detailed mechanistic understanding of fatty acid synthesis as an important part of parasite metabolism and metabolic host-parasite interaction. Mutant analysis will highlight truly essential components as potential pharmacological targets. We also expect that the genetic and metabolomic tools honed along the way will prove highly useful for the dissection of many facets of parasite biology beyond lipid metabolism. PUBLIC HEALTH RELEVANCE: This project will use modern genetic and metabolomic approaches to dissect the metabolism of the human pathogen Toxoplasma gondii. The studies will provide important information to guide the development of drug treatments and will lead to a detailed understanding of host-parasite interaction at the metabolic level.

描述（由申请人提供）：该提案概述了一个综合计划，以剖析人类病原体弓形虫的脂肪酸代谢。 gondii感染在美国普遍存在（22％的人口被长期感染），而通常良性会引起免疫抑制个体的威胁生命的疾病（例如，患有HIV-AID，移植受者或血液系统恶性肿瘤的人）。先天性的贡迪（T. gondii）也是公共卫生的主要关注点。高度毒性的寄生虫菌株最近被确定为严重且反复出现的眼感染的原因，最终导致失明。 T. gondii也有可能引起大量的水传播暴发，并已被疾病预防控制中心（CDC）列为潜在的生物恐怖病原体（附录B）。当前可用的治疗频繁且明显的不良反应，并且在慢性感染中没有疗效，因此允许体现活性感染。因此，迫切需要新药。在Apicomplexan寄生虫中发现类似叶绿体的细胞器为药物发育提供了几种有希望的寄生虫特异性靶标途径。在这些途径中，有一项细菌II型脂肪酸合成途径，该途径中的酶一直是针对疟疾和弓形虫病的强化药物化学努力的主题。然而，该途径的t. gondii和相关的Apicomplexan寄生虫的确切功能尚不清楚。此外，寄生虫基因组编码可能通过合成或从宿主细胞挽救的脂肪酸提供的其他酶系统。需要对这些途径的功能和相对重要性有详细的理解，以指导药物开发工作为最有希望的目标。在这个项目中，我们将使用遗传学和代谢组学来剖析三种单个途径的复杂相互作用。使用一种新颖且高效的方法来设计有条件的T. gondii突变体，我们将严格测试体内每个单独途径的重要性和功能。我们将使用无偏的代谢组分析确定特定途径损失对寄生虫脂肪酸和脂质组成的影响。为了定义单个途径之间以及寄生虫与其宿主细胞之间的相互作用，我们使用稳定的表位跟踪进行代谢通量研究。总体而言，我们预计概述的研究将对脂肪酸合成作为寄生虫代谢和代谢宿主寄生虫相互作用的重要组成部分产生详细的机械理解。突变分析将重点介绍真正必不可少的成分作为潜在的药理学靶标。我们还期望沿途磨练的遗传和代谢组工具对除脂质代谢以外的许多寄生虫生物学方面的解剖而言非常有用。公共卫生相关性：该项目将采用现代遗传和代谢组方法来剖析人类病原体弓形虫的代谢。这些研究将提供重要的信息来指导药物治疗的发展，并将导致对代谢水平上宿主 - 寄生虫相互作用的详细了解。