Targeting host deubiquitinases for broad spectrum anti-infective therapy

迫切需要有效针对抗药性的新疗法。 目前没有治疗选择的微生物和病原体。诺如病毒导致 估计有2300万人感染，超过一半的食源性胃肠炎暴发 美国每年都有这种病毒，但目前还没有抗病毒药物或疫苗来治疗或预防感染。 单核细胞增多性李斯特菌是另一种食源性致病菌，致死率高达20%- 25%，对最近与哈密瓜有关的疫情负有责任。快速诊断一种 暴发期间的特定病原体通常是具有挑战性的。因此，有一个令人信服的 开发早期有效的广谱疗法的理论基础 传染病的治疗。实现这一目标的一种方法是开发“反 以宿主编码的蛋白质为靶标的具有感染性的化合物 多种微生物。我们发现一种小分子，WP1130(WP)和相关的 化合物对多种病原体表现出抗感染活性，包括 几种B类病原体：细菌(MRSA、单核细胞增生性李斯特菌、沙门氏菌 肠道病毒(鼠伤寒沙门氏菌)、病毒(鼠和人诺如病毒、 脑心肌炎病毒、辛德比斯病毒、拉克罗斯病毒)和心尖复合体 寄生虫(弓形虫)。我们的初步研究表明可湿性粉剂抑制了一个子集 宿主去泛素酶(DUBS)导致泛素化蛋白在 细胞，但不直接影响寄主以外的病原体。泛素是一种真核生物 低分子量多肽在以下情况下充当翻译后调节开关 与目标蛋白共价连接。对可湿性粉剂类似物的研究为 通过干扰有效抑制病原体的新疗法的开发 与宿主和微生物之间的关键相互作用有关。泛素化和去泛素化 宿主靶标在许多不同的微生物感染中起着关键作用。因此，我们 假设可湿性粉剂治疗选择性地抑制由 微生物病原体，从而限制感染。我们将使用小鼠诺沃克病毒和L. 作为两种无关病原体的单核细胞增多症与已建立的小动物模型 确定介导可湿性粉剂抗感染作用的复制靶点。我们的目标是 将先导化合物推向研究性新药(IND)应用。 因此，我们提出了以下具体目标：(1)确定可湿性粉剂的目标配音 介导抗感染活性，(2)体外检测一系列可湿性粉剂的SAR以鉴定铅 以及(3)测试先导化合物的体内疗效。此应用程序旨在 开发对多种病原体有效的广谱抗感染治疗 包括多个B类特工。

There is an urgent need for new therapeutics that effectively target drug-resistant microbes and pathogens that currently have no treatment options. Noroviruses cause an estimated 23 million infections and over half of all food-borne gastroenteritis outbreaks in the US every year but no antivirals or vaccines exist to treat or prevent infections. Listeria monocytogenes is another food-borne pathogen with a high fatality rate of 20- 25%, responsible for the recent cantaloupe-associated outbreak. Rapid diagnosis of a specific pathogen during outbreaks is often challenging. Thus, there is a compelling rationale for the development of broad-spectrum therapeutics for early and effective treatment of infectious diseases. One approach towards that goal is to develop “anti- infective” compounds that target host-encoded proteins critical during infection of multiple microbes. We find that a small molecule, WP1130 (WP) and related compounds, exhibit anti-infective activity against multiple classes of pathogens, including several category B pathogens: bacteria (MRSA, Listeria monocytogenes, Salmonella enterica serovar Typhimurium), viruses (murine and human norovirus, encephalomyocarditis virus, Sindbis virus, La Crosse virus), and an apicomplexan parasite (Toxoplasma gondii). Our initial studies demonstrate that WP inhibits a subset of host deubiquitinases (DUBs) resulting in the accumulation of ubiquitinated proteins in cells, but does not directly affect pathogens outside the host. Ubiquitin is a eukaryotic low molecular weight polypeptide that acts as a post-translational regulatory switch when covalently linked to target proteins. Studies of WP analogs hold vital clues for the development of novel therapeutics that may effectively contain pathogens by interfering with key interactions between host and microbe. Ubiquitination and deubiquination of host targets play critical roles in many different microbial infections. We therefore hypothesize that WP treatment selectively inhibits key DUBs exploited by microbial pathogens, thereby limiting infection. We will use murine norovirus and L. monocytogenes as two unrelated pathogens with established small animal models of infection to define DUB targets that mediate the anti-infective effects of WP. Our goal is to advance the lead compound towards an investigational new drug (IND) application. We therefore propose the following specific aims: (1) Determine target DUBs of WP that mediate anti-infective activity, (2) Test a SAR series of WP in vitro to identify lead compounds, and (3) Test lead compounds for in vivo efficacy. This application aims to develop a broad-spectrum anti-infective therapeutic effective against many pathogens including multiple category B agents.