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”）在感染通常非常特定的细菌宿主方面具有很高的效率。一般来说，成功感染一个细菌只需要一个或几个病毒颗粒。因此，噬菌体被用作抗生素的希望一直没有实现。对替代抗生素的需求正变得越来越迫切，因为常见的细菌病原体正在产生耐药突变，因此迫切需要开发噬菌体疗法等替代品。此外，重组噬菌体被认为是基因治疗的一种手段，也是开发疫苗的潜在抗原。T4噬菌体是研究病毒结构和功能的模型系统，具有先进的生物复合物组装和蛋白-蛋白相互作用的生化原理。我们在T4噬菌体的结构和功能研究方面有着丰富的经验。我们现在希望扩大这方面的知识，使其可用于潜在的医疗应用。计划分析衣壳的结构和组装（Specific Aim 1）、DNA包装机（Specific Aim 2）、尾部组装（Specific Aim 3）、尾部与头部的组装（Specific Aim 4）以及噬菌体纤维对宿主的识别（Specific Aim 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。分子生物学研究将为结构和功能研究提供足够数量的纯样品。晶体学研究将是蛋白质成分，提供接近原子分辨率的三维信息。低温电子显微镜重建将提供病毒内蛋白质成分组织的三维数据。结合这些技术将生成病毒生命周期不同阶段的“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.