Inhibitors of Nitro Drug Targets as Antimicrobials against Trichomonas Vaginalis

 描述（由申请人提供）：单细胞寄生虫阴道毛滴虫是全球最流行的非病毒性性传播感染的原因，每年约有1/4亿人感染滴虫病。毛滴虫病是美国最常见的寄生虫感染，估计每年有500万例。感染频率和耐药临床分离株的增加。寄生虫病强调需要开发新的化学治疗策略和药物来消除寄生虫。对唯一获准用于治疗的药物5-硝基咪唑（5 NI）药物甲硝唑（Mz）和替硝唑（Tz）的耐药性发生在大约5%的滴虫病病例中。5 NI是通过厌氧微生物内的选择性还原而激活的前药，这是杀死微生物的关键步骤，但也是当微生物在厌氧微生物中生长时产生耐药性的原因。 失去了减少5 NI的能力。在活化时，5 NI通过与基本靶分子形成共价的、失活的加合物来杀死细胞，所述基本靶分子定义不清楚。本文提出的研究的长期目标是确定5 NI药物的微生物靶点，这些靶点对T. vagonists和利用这一信息开发蛋白质靶点的抑制剂，有效治疗耐药性滴虫病。这些研究有五个具体目标。前两个目标将在R21阶段实现，后三个目标将在R33阶段实现。在目标1中，我们将确定模型T中的硝基药物靶标。使用采用点击化学和质谱分析的策略，在目标2中，我们将确定哪些蛋白质靶标是T。使用反向遗传学来测试基因的消除是否是致命的。在过渡到R33阶段后，在目标3中，我们将确定广泛的地理和遗传多样性T细胞所共有的硝基药物靶标。迷走神经临床分离株。在目标4中，我们将确定目标3中确定的选定的共同靶标是否是寄生虫生存所需的。在目标5中，我们将开发最有希望的硝基药物靶点的抑制剂，并在体外和体内检测抑制剂活性。 vivo.最后，我们的目标是验证新的药物靶点，并开发针对这些靶点的新抑制剂，作为有效治疗Mz耐药滴虫病的候选药物。拟议的研究还将为使用相同的方法来识别和验证新的抗菌药物以治疗其他厌氧寄生虫感染铺平道路，例如贾第虫病和阿米巴病，Mz是用于治疗的主要药物。

 DESCRIPTION (provided by applicant): The unicellular parasite Trichomonas vaginalis is responsible for the most prevalent, non-viral, sexually-transmitted infection worldwide, with approximately 1/4 billion people contracting trichomoniasis annually. Trichomoniasis is the most common parasitic infection in the US and has an annual incidence estimated at 5 million cases. The frequency of infection and an increase in the number of drug resistant clinical isolates of T. vaginalis underscore the need to develop new chemotherapeutic strategies and drugs that eliminate the parasite. Resistance to the only drugs licensed for therapy, the 5-nitroimidazole (5NI) drugs metronidazole (Mz) and tinidazole (Tz), occurs in approximately 5% of cases of trichomoniasis. 5NIs are prodrugs that are activated by selective reduction inside anaerobic microbes, a step that is critical for killing, but also responsible for resistance when the microbe loses its capacity to reduce 5NIs. Upon activation, 5NIs kill the cell by forming covalent, inactivating adducts with essential target molecules, which are poorly defined. The long-term goal of the research proposed here is to define microbial targets of 5NI drugs that are essential for the survival of T. vaginalis and leverage this information to develop inhibitors of protein targets that are effective in the treatment of drug resistant trichomoniasis. The proposed studies have five Specific Aims. The first two aims will be achieved during the R21 phase and the latter three during the R33 phase. In Aim 1, we will identify nitro drug targets in model T. vaginalis strains using a strategy that employs click chemistry and mass spectrometry. In Aim 2, we will determine which protein targets are essential for T. vaginalis viability using reverse genetics to test whether elimination of the gene is lethal. After transitioning to the R33 phase, in Aim 3 we will identify nitro drug targets that are common to a broad range of geographically and genetically diverse T. vaginalis clinical isolates. In Aim 4, we will determine whether selected, common targets identified in Aim 3 are required for parasite viability. In Aim 5 we will develop inhibitors for the most promising nitro drug targets and examine inhibitor activity in vitro and in vivo. In the end, we aim to have validated novel drug targets and developed new inhibitors against these targets as candidates for effective treatment of Mz resistant trichomoniasis. The proposed research will also pave the way for using the same approach to identify and validate new antimicrobials to treat other anaerobic parasitic infections, such as giardiasis and amoebiasis, for which Mz is the primary drug used for therapy.