Bacterial-mediated enhancement of Coxsackievirus

项目摘要 柯萨奇病毒是一种常见的感染，可引起病毒性心肌炎、脑膜脑炎和手、足、 儿童和成人的口腔疾病。柯萨奇病毒通过粪-口途径传播， 在胃肠道中。目前，缺乏有效的预防和治疗方案， 柯萨奇病毒感染。使用小鼠模型，最近的数据表明，柯萨奇病毒B3（CVB 3） 利用细菌帮助病毒在体内复制和致病。然而，这种观察的机制是 不清楚在初步数据中，我们已经证明细菌可以增强CVB 3的感染性， 体外热稳定性我们还发现，革兰氏阴性沙门氏菌与CVB 3结合， CVB 3的感染性和稳定性，而大肠杆菌没有。我们还发现主细胞中的结构 沙门氏菌的壁组分脂多糖（LPS）可影响病毒稳定性。这些数据表明 需要特定的细菌和细菌细胞壁组分来增强CVB 3。因此，本研究的目的是 阐明细菌结构和结合CVB 3的位点，并研究细菌 有助于病毒的热稳定性。这一目标将通过三个目标来实现。在目标1中，我们将确定 与CVB 3相互作用的细胞壁成分。使用沙门氏菌LPS突变体，我们将表征关键的 与CVB 3相互作用所需的LPS元件。在目标2中，我们将确定细菌之间的病毒体结合位点 和柯萨奇病毒使用最先进的低温电子显微镜和CVB 3突变体的组合， 我们将阐明CVB 3病毒粒子上的LPS足迹。最后，在目标3中，我们将确定 脂多糖对CVB 3感染性和病毒稳定性的影响。总体而言，该项目将对我们的 了解病毒-微生物区系的相互作用，并帮助未来的研究，以确定抗病毒的目标， 开发新的治疗方法。

Project Summary Coxsackievirus is a common infection that causes viral myocarditis, meningoencephalitis, and hand, foot, and mouth disease in children and adults. Coxsackievirus is transmitted by the fecal-oral route and initiates infection in the gastrointestinal tract. Currently, there is a lack of effective prevention and treatment options for Coxsackievirus infections. Using a mouse model, recent data demonstrate that Coxsackievirus B3 (CVB3) utilizes bacteria to aid viral replication and pathogenesis in vivo. However, the mechanism for this observation is unclear. In preliminary data, we have demonstrated that bacteria can enhance CVB3 infectivity and thermostability in vitro. We also found that Gram-negative Salmonella enterica binds to CVB3 and can enhance infectivity and stability of CVB3 while Escherichia coli does not. We also found that structures in the major cell wall component of Salmonella, lipopolysaccharide (LPS), can impact viral stability. These data suggest that specific bacteria and bacterial cell wall components are required to enhance CVB3. Therefore, this study aims to elucidate the bacterial structure and site of binding to CVB3, and investigate the mechanisms by which bacteria aid viral thermostability. This goal will be accomplished in three aims. In Aim 1, we will determine the bacterial cell wall components that interact with CVB3. Using Salmonella LPS mutants, we will characterize the critical elements of LPS required to interact with CVB3. In Aim 2, we will identify the virion binding site between bacteria and Coxsackievirus. Using a combination of state-of-the-art cryogenic electron microscopy and CVB3 mutants, we will elucidate the LPS footprint on the CVB3 virion. Finally, in Aim 3, we will determine the effect of lipopolysaccharide on CVB3 infectivity and viral stability. Overall, this project will significantly impact our understanding of viral-microflora interactions and aid future studies to identify antiviral targets for the development of novel therapeutics.