Bacterial-type hexokinase (HK) in the opportunistic parasite Cryptosporidium parv

机会性寄生虫隐孢子虫中的细菌型己糖激酶 (HK)

• 批准号: 8730780
• 负责人: GUAN ZHU
• 金额: $ 21.44万
• 依托单位: TEXAS A&M AGRILIFE RESEARCH
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8730780
• 关键词: Acquired Immunodeficiency Syndrome; Animal Model; Animals; Bacterial Typing; Biochemical; Biological Assay; Categories; Cessation of life; Chemicals; Chlorine; Cities; Coccidia; Communities; Cryptosporidiosis; Cryptosporidium; Cryptosporidium parvum; Data; Development; Diarrhea; Diphosphates; Disease Outbreaks; Drug Targeting; Drug resistance; Entamoeba; Enzymes; Future; Glycolysis; Goals; Growth; Human; Immunocompetent; Immunocompromised Host; In Vitro; Individual; Infection; Kinetics; Laboratories; Lactate Dehydrogenase; Lead; Libraries; Life; Metabolic; Metabolic Pathway; Molecular; Morbidity - disease rate; Oocysts; Parasites; Pathway interactions; Patients; Pharmaceutical Preparations; Process; Protein Isoforms; Proteins; Reaction; Resistance; Side; Stress; Structure-Activity Relationship; Testing; Translational Research; Trichomonas; Trypanosoma; United States; United States National Institutes of Health; Water; Water Supply; Wisconsin; analog; base; biodefense; drug development; drug discovery; enzyme activity; foodborne; foodborne pathogen; gastrointestinal epithelium; genome sequencing; hexokinase; high throughput screening; inhibitor/antagonist; mortality; nitazoxanide; novel therapeutics; pathogen; programs; public health relevance; research study

DESCRIPTION: Cryptosporidium parvum is an AIDS-OI pathogen and Category B agent. It is a significant water- and food-borne protozoan parasite that can cause severe watery diarrhea in humans and animals. Currently, only a single drug (i.e., nitazoxanide [NTZ]) is approved for treating cryptosporidiosis in immunocompetent (but not immunocompromized) patients in the United States. However, NTZ is not 100% effective against cryptosporidiosis. Potential drug resistance may also be developed in Cryptosporidium, similar to the drug resistance problem in malarial parasites and coccidia. Therefore, there is an urgent need to develop new anti-Cryptosporidium drugs. Our long-term goal of this translational research is to characterize the molecular and biochemical features of the essential enzymes in the C. parvum glycolytic pathway as potential drug targets. Because C. parvum relies solely on glycolysis for its energy, we hypothesize that the bacterial-type CpHK responsible for the entry step of reaction in the glycolytic pathways could serve as rational drug targets in this parasite. To test the hypothesis, we will perform experiments to characterize the biochemical features of CpHK and identify CpHK inhibitors for future drug development via HTS of compound libraries, characterize the inhibitory kinetics of top hits, and test their efficacies against C. parvum growth in vitro. The major goal of this exploratory/developmental R21 project is to identify hits that inhibit both CpHK enzyme activity and the parasite growth in vitro, which would produce conclusive data for further studying the mechanism of inhibition, structure-activity relationship, and to synthesize new analogs of hits for lead optimization, as well as to assess the efficacies of hits and leads agains cryptosporidial infection in animal models.

描述：parvum隐孢子虫是AIDS-OI病原体和B类药物。这是一种重要的水和食源原生动物寄生虫，可导致人类和动物的严重水性腹泻。目前，在美国，仅批准一种一种药物（即硝酸氧氧化物[NTZ]）治疗隐孢子虫病（但不是免疫功能低下）患者。然而，NTZ对隐孢子虫病的有效效率不是100％。潜在的耐药性也可以在隐孢子虫中发展，类似于疟疾寄生虫和球虫的耐药性问题。因此，迫切需要开发新的抗氯孢子虫药物。这项翻译研究的长期目标是将基本酶在糖糖糖溶解途径中的分子和生化特征表征为潜在的药物靶标的分子和生化特征。由于C. parvum仅依赖于糖酵解的能量，因此我们假设负责在糖酵解途径中反应步骤的细菌型CPHK可以作为该寄生虫中的有理药物靶标。为了检验该假设，我们将执行实验以表征CPHK的生化特征，并通过复合文库的HTS鉴定CPHK抑制剂，以通过复合文库的HTS发育，表征最高命中的抑制性动力学，并测试其在体外生长的效果。该探索性/发展性R21项目的主要目标是确定抑制这两个CPHK的命中 酶活性和体外的寄生虫生长将产生结论性数据，以进一步研究抑制作用，结构活性关系的机制，并合成铅的新型类似物以进行铅优化，并评估动物模型中的hits和铅的效率。