Structural studies of bacteriophage T4 and their potential medical applications

描述（由申请人提供）：大多数细菌病毒（“噬菌体”或简称“噬菌体”）在感染其通常非常特异的细菌宿主的能力方面是高效的。一般来说，只有一个或几个病毒颗粒是必要的成功感染一个细菌。因此，长期以来一直存在着一个未实现的希望，即β-内酰胺酶可以用作抗生素。对替代抗生素的需求变得越来越迫切，因为常见的细菌病原体正在产生耐药性突变，迫切需要开发噬菌体疗法等替代药物。此外，已建议将重组人β-内酰胺酶作为基因治疗的手段和作为疫苗开发的潜在抗原。 噬菌体T4是研究病毒结构和功能的模型系统，具有生物复合物组装和蛋白质-蛋白质相互作用的先进生物化学原理。我们在噬菌体T4的结构和功能研究方面都有丰富的经验。我们现在希望扩展这些知识，并使其可用于潜在的医学应用。 计划分析衣壳的结构和组装（特异性目的1）、DNA包装机（特异性目的2）、尾部组装（特异性目的3）、尾部与头部的组装（特异性目的4）以及噬菌体纤维对宿主的识别（特异性目的5）。我们的主要工具将是分子生物学，蛋白质化学，晶体学和电子显微镜。分子生物学研究将产生足够数量的纯样品用于结构和功能研究。晶体学研究将是蛋白质成分，提供近原子分辨率的三维信息。冷冻电子显微镜重建将提供病毒内蛋白质组分组织的三维数据。结合这些技术将产生病毒在其生命周期的不同阶段的“伪原子”分辨率结构。

DESCRIPTION (provided by applicant): Most bacterial viruses ("bacteriophages" or just "phages") are highly efficient in their ability to infect their often very specific bacterial hosts. In general, only one or a few viral particles are necessary to successfully infect one bacterium. As a consequence there has been a long, unfulfilled hope that phages could be used as antibiotics. The need for alternative antibiotics is becoming ever more acute as common bacterial pathogens are developing resistant mutations, making it urgent to develop alternatives such as phage therapy. In addition, recombinant phages have been suggested as a means for gene therapy and as potential antigens for development of vaccines. Bacteriophage T4 has been a model system to study virus structure and function, having advanced biochemical principles of the assembly of biological complexes and protein-protein interactions. We have extensive experience in both structural and functional studies of phage T4. We now wish to expand this knowledge and make it available for potential medical applications. The plan is to analyze the structure and assembly of the capsid (Specific Aim 1), the DNA packaging machine (Specific Aim 2), the tail assembly (Specific Aim 3), assembly of the tail with head (Specific Aim 4) and the recognition of the host by the phage fibers (Specific Aim 5). Our primary tools will be molecular biology, protein chemistry, crystallography and electron microscopy. Molecular biology studies will produce pure samples in sufficient quantity for structural and functional studies. Crystallographic studies will be of protein components, providing three-dimensional information at near atomic resolution. Cryo-electron microscopic reconstructions will provide three-dimensional data on the organization of the protein components within the virus. Combining these techniques will generate "pseudo-atomic" resolution structures of the virus at different stages of its life cycle.