HOST RANGE DIVERSITY OF BACTERIOPHAGE FOR Y. PESTIS

描述（由申请人提供）：鼠疫耶尔森氏菌（Yersinia pestis）是鼠疫的致病菌，属于A类病原体，是一种重要的生物战剂。如果武器化，它可以很容易地直接进入呼吸系统，导致肺鼠疫迅速死亡。鼠疫的死亡率超过50%，具有高度传染性，如果细菌被设计成抵抗抗生素，基本上是不可战胜的。作为对这种威胁的对策，我们建议开发一个针对Y.鼠疫杆菌，可以杀死多种菌株的这种细菌以高效的方式。AvidBiotics拥有独家技术，可以产生具有高度多样性尾部的噬菌体家族，这些噬菌体能够与细菌的突变形式结合，例如博德特氏菌。在本申请中，我们提出开发噬菌体库以结合、感染和杀死突变体Y。鼠疫细菌，预计潜在的突变工程到细菌，以改变其敏感性的抗生素或表面受体的噬菌体。这项技术是基于发现一个家庭的多样性产生的逆转录元件（DGRs）的功能，以改变DNA序列和蛋白质，他们编码。这些DGRs可以被工程化到噬菌体尾丝中，以特异性地多样化噬菌体尾丝的精确受体结合位点的氨基酸序列，从而产生具有超过万亿种不同的靶向Y的可能尾的噬菌体文库。鼠疫菌细胞表面受体通过将这样的噬菌体文库暴露于突变的或武器化的鼠疫细菌，可以鉴定、选择、分离、扩增、雾化能够感染、增殖和杀死细菌的细菌，然后部署以防止或治疗由武器化的Y。鼠疫本申请的目的是证明利用DGR系统精确和广泛地使噬菌体尾纤维序列多样化的能力，作为产生具有宽Y的新型噬菌体的手段。鼠疫趋性这些研究将为未来的研究提供基础，以产生一个合适的，配制的高度多样化的细菌，将作为一个可靠的，生产性的诊断和治疗剂的有效来源，对武器化的鼠疫细菌。我们预计，II期后续项目将需要开发GLP生产工艺，并制定靶向Y的多种噬菌体文库的代表性成员。并进行临床前安全研究，以建立一个快速反应的反恐系统，管理人类肺鼠疫。

DESCRIPTION (provided by applicant): Yersinia pestis, the bacterium responsible for plague, is a Category A pathogen, a significant biowarfare agent. If weaponized, it can easily gain direct access to the respiratory system to cause rapid death by pneumonic plague. Pneumonic plague has fatality rates over 50%, is highly contagious, and if the bacteria are engineered to resist antibiotics, is essentially unbeatable. As a countermeasure to such a threat, we propose to develop a library of bacteriophages ("phages") specific for Y. pestis that can kill multiple strains of this bacterium in a highly efficient manner. AvidBiotics has exclusive access to technology to generate families of phage with highly diverse tails capable of binding to mutant forms of bacteria, such as Bordetella. In this application, we propose to develop a library of phage to bind to, infect and kill mutant Y. pestis bacteria, anticipating potential mutations engineered into the bacteria to change their sensitivities to antibiotics or surface receptors for phage. This technology is based on the discovery of a family of diversity-generating retroelements (DGRs) that function to vary DNA sequences and the proteins they encode. These DGRs can be engineered into phages to diversify specifically the amino acid sequence of the precise receptor-binding site of the phage tail fiber, thereby generating a library of phages with more than a trillion different possible tails targeting Y. pestis cell surface receptors. By exposing such a phage library to mutant or weaponized plague bacteria, phages capable of infecting, multiplying and killing the bacteria could be identified, selected, isolated, amplified, aerosolized and then deployed to protect against or treat infections by weaponized Y. pestis. The objective of this application is to demonstrate the ability to utilize the DGR-system to precisely and extensively diversify the phage tail fiber sequences as a means to create novel phage with broad Y. pestis tropism. These studies will provide the foundation for future studies to generate a suitable, formulated pool of highly diverse phages that will serve as a reliable, productive source of diagnostic and therapeutic agents effective against weaponized plague bacteria. We anticipate that a Phase II follow-on project would entail developing a process to GLP manufacture and formulate representative members of the diverse phage library targeting Y. pestis and conduct pre-clinical safety studies to prepare a rapid response counter- terrorism system to manage pneumonic plague in humans.