Giardia drug targets: Structure, function and inhibitors

贾第鞭毛虫药物靶点：结构、功能和抑制剂

• 批准号: 7172325
• 负责人: OSNAT HERZBERG
• 金额: $ 56.97万
• 依托单位: UNIVERSITY OF MD BIOTECHNOLOGY INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-02-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7172325
• 关键词: Active Sites; Adverse effects; Affect; Binding; Biochemical; Biological; Biological Assay; Biological Warfare; Biotechnology; Bioterrorism; Categories; Centers for Disease Control and Prevention (U.S.); Clinical; Cloning; Collaborations; Complex; Country; Crystallization; Databases; Dependence; Developed Countries; Developing Countries; Diarrhea; Disease Outbreaks; Drug Delivery Systems; Enzyme Inhibitor Drugs; Enzyme Inhibitors; Enzymes; Escherichia coli; Evaluation; Food Supply; Genes; Genetic Transcription; Genome; Genomics; Giardia; Giardia lamblia; Giardiasis; Goals; Growth; Human; Immunocompetent; Immunocompromised Host; In Vitro; Institutes; Kinetics; Laboratories; Ligands; Maryland; Methods; Molecular; New Mexico; Organism; Parasites; Patients; Pharmaceutical Preparations; Population; Production; Property; Proteins; Protozoa; Range; Rate; Recombinant Proteins; Recurrence; Research; Resistance; Roentgen Rays; Sequence Analysis; Solubility; Specificity; Structure; Techniques; Testing; United States; United States National Institutes of Health; Universities; Validation; Water; Work; X-Ray Crystallography; analog; base; cofactor; design; foodborne; genome sequencing; improved; inhibitor/antagonist; insight; multidisciplinary; pathogen; pre-clinical; size; waterborne

DESCRIPTION (provided by applicant): Giardia lamblia is a food and waterborne parasite prevalent in developing countries, and a major cause of outbreaks of diarrhea in the United Sates, that has been classified as a bioterrorism category B organism by the Center for Disease Control because compromised water and food supply could affect US populations as well as army units in foreign countries. Drugs commonly used against anaerobic protozoa are used to treat giardiasis. However, they produce undesirable side effects, clinical resistance may occur in both immunocompromised and immunocompetent patients, and the rate of recurrence is high. The goal of this project is to develop new drug targets for alternative treatments of giardiasis. The sequence of the G. lamblia genome is available, thus, a genomic approach combined with biological insight has been taken to identify enzymes essential for the survival of the organism that are absent or are sufficiently divergent from the human enzymes to exploit those differences in the design of inhibitors. The selected enzymes will be cloned and expressed in E. coli using high throughput techniques, and those that are expressed in soluble form will be validated in G. lamblia by transcription interference methods. Essential enzymes will be prepared for structural and functional studies. Crystal structures will be determined, and will serve to guide the design of inhibitors specific to the Giardia enzymes. Assays to determine the kinetic constants of the enzymes will be developed and the catalytic mechanism will be studied to facilitate the in vitro evaluation of the inhibitors. Crystal structures of enzyme/inhibitor complexes will reveal how the inhibitor may be further improved. The effect of the inhibitors on the growth of G. lamblia will be determined. The long range goals of the project is to establish a database of potential drug targets against giardiasis, to gain insight about their mechanism of action, and to prepare inhibitors that are ready for preclinical evaluation.

描述（由申请人提供）：贾第鞭毛虫是一种在发展中国家普遍存在的食物和水源性寄生虫，也是美国腹泻爆发的主要原因，已被疾病控制中心列为生物恐怖主义 B 类生物，因为水和食物供应受损可能会影响美国民众以及驻扎在外国的军队。通常用于对抗厌氧原虫的药物用于治疗贾第鞭毛虫病。然而，它们会产生不良副作用，在免疫功能低下和免疫功能正常的患者中都可能出现临床耐药，并且复发率很高。该项目的目标是开发贾第鞭毛虫病替代疗法的新药物靶点。 G. Lamplia 基因组的序列是可用的，因此，采用基因组方法与生物学见解相结合来识别生物体生存所必需的酶，这些酶不存在或与人类酶有足够的差异，以利用抑制剂设计中的这些差异。选定的酶将使用高通量技术在大肠杆菌中克隆和表达，而那些以可溶形式表达的酶将通过转录干扰方法在兰氏酵母中进行验证。将为结构和功能研究准备必需的酶。晶体结构将被确定，并将用于指导贾第鞭毛虫酶特异性抑制剂的设计。将开发确定酶动力学常数的测定方法，并研究催化机制，以促进抑制剂的体外评估。酶/抑制剂复合物的晶体结构将揭示如何进一步改进抑制剂。将测定抑制剂对G.兰伯利亚生长的影响。该项目的长期目标是建立贾第鞭毛虫病潜在药物靶点数据库，深入了解其作用机制，并制备可供临床前评估的抑制剂。