Aptamer-Enabled Modification of Bacteriophage Host Range

项目摘要 “超级细菌”一词在公众意识中让人联想到讨厌的细菌， 抗生素治疗，一个公共卫生威胁进一步加剧了新的抗生素供应的减少， 发展管道。不谨慎地使用广谱抗生素也会对有益的微生物群有害。 随着新的紧迫性，美国国立卫生研究院将噬菌体治疗列为七个方面之一， 其对抗抗生素耐药性的计划。噬菌体（Bacteriophage，缩写为BPHs）是一种只感染和杀死细菌的病毒。 噬菌体治疗是将细菌作为杀菌剂靶向应用于治疗细菌感染。然而，在这方面， 为了更好地应对新出现和不断演变的细菌病原体，所有治疗性和预防性噬菌体 产品需要定期更新，这将不可避免地增加产品维护的成本。的 “自然产品”的不可专利性进一步减少了商业实体参与 研究和开发（R&D），以实现噬菌体治疗的全部潜力。 在这里，我们提出了一种创新的方法来绕过可能困扰 传统的全噬菌体产品，同时为研发提供激励， 容易获得和保护的财产。我们的建议是可能的，最近的研究，揭示 噬菌体识别宿主所涉及的复杂步骤以及识别信号如何能够触发 噬菌体尾部的预编程构象变化，最终导致噬菌体DNA的递送 基因组进入受感染的细菌细胞，从而杀死它。我们利用广泛研究的经典， T4和T7以及它们的宿主大肠杆菌作为模型系统，以检验人工 可以触发拴系噬菌体将其DNA基因组递送到非宿主细胞中。 在该方案中，噬菌体拴系通过化学稳定的RNA适体实现，所述RNA适体特异性结合至 噬菌体尾纤维、噬菌体的受体结合蛋白以及结合到表面的那些 E.杆菌通过将这两种适体偶联在一起， 物理上接近细胞表面，这是成功感染的先决条件。根据这一假设， 附着的噬菌体所经历的布朗运动将触发噬菌体的预先编程的部署。 噬菌体尾中涉及的蛋白质，使得可以递送DNA基因组。我们将使用公认的 分子育种过程，称为SELEX，以产生所需的适体。 我们提出的研究代表了一个独特的解决方案的问题，特别是可扩展性和 可专利性-使用噬菌体作为细菌感染的治疗和预防剂时遇到的问题。 如果这项概念验证研究的结果令人鼓舞，我们相信我们将能够开辟一个全新的 和有影响力的研究收入。

Project Summary The term “superbug” conjures up in public consciousness the imagery of nasty bacteria recalcitrant to antibiotic treatments, a public health threat further heightened by the dwindling supply of new antibiotics in the development pipeline. Imprudent use of broad-spectrum antibiotics is also harmful to the beneficial microbiota. With the renewed urgency, the US National Institutes of Health listed phage therapy as one of seven prongs in its plan to combat antibiotic resistance. Bacteriophages (phages) are viruses that only infect and kill bacteria. Phage therapy is the targeted application of phages as bactericidal agent to treat bacterial infections. However, to better respond to emerging and evolving bacterial pathogens, all therapeutic and prophylactic phage products will require periodic updates, which will inevitably incur further cost in product maintenance. The unpatentability of “product of nature” further reduces incentives for commercial entities to participate in the research and development (R&D) to realize the full potential of phage therapy. Here we propose an innovative approach to bypass the required updates that can plague the conventional whole-phage products, and at the same time provide an incentive for R&D with an intellectual property that is easily securable and defendable. Our proposal is made possible by recent studies, revealing intricate steps involved in host recognition by a phage and how the signal of recognition is able to trigger the preprogrammed conformational changes in the phage tail that eventually leads to the delivery of phage DNA genome into the infected bacterial cell, thus killing it. We take advantages of the extensively studied classics, T4 and T7, and their host, Escherichia coli, as the model system to test the hypothesis that an artificially tethered phage can be triggered to deliver its DNA genome into a non-host cell. In this scheme, phage tethering is achieved by chemically stable RNA aptamers that specifically bind to the phage tail fiber, the receptor-binding protein of the phage, and those that bind to the surface macromolecules of E. coli. By coupling together these two types of aptamers, we can bring a phage to close physical proximity of the cell surface, a pre-requisite for a successful infection. Based on the hypothesis, the Brownian motion, experienced by an attached phage, will trigger the preprogrammed deployment of the proteins involved in phage tail such that the DNA genome can be delivered. We will use the well-established molecular breeding process, called SELEX, to generate the required aptamers. Our proposed study represents a unique solution to the problems—especially the scalability and the patentability—encountered by using phage as a therapeutic and prophylactic agent against bacterial infection. If the result is encouraging from this proof-of-concept study, we believe we will be able to open an entirely new and impactful revenue of research.