BACTERIOPHAGE EPSILON 15

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 噬菌体Epsilon15是一种感染人/动物病原体肠出血性沙门氏菌的通用转导噬菌体。Epsilon 15因其识别和结合O-抗原的能力以及在溶原性状态下改变宿主内毒素的能力而被研究。负责识别O抗原的病毒蛋白是尾钉蛋白。该病毒粒子含有至少6个结构蛋白和一个约40kb的已知序列的dsDNA基因组。在序列水平上，结构蛋白与伯克霍尔德氏菌的Bcep噬菌体最相似，伯克霍尔德氏菌是一种影响囊性纤维化患者的人类病原体。病毒粒子结构蛋白和染色体共同构成一个质量约为66兆吨、直径约为650埃的粒子。乔恩·金的实验室使用质谱学方法来鉴定编码病毒粒子结构蛋白的开放阅读框。这种病毒的结构将揭示结构蛋白的排列，特别是那些与宿主连接和DNA进入细胞质更直接相关的亚基的配置。目前正在进行一种遗传方法来分离病毒结构蛋白中的琥珀突变体。在感染这些突变噬菌体过程中形成的大分子亚组件将通过重建进行纯化和成像。这些突变的噬菌体还将作为试剂，用于成像病毒与宿主表面的内毒素和受体蛋白之间的相互作用。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Bacteriophage Epsilon15 is a generalized transducing phage infecting the human/animal pathogen Salmonella enterica serovar Anatum. Epsilon 15 has been studied for its ability to recognize and bind O-antigen as well as its capacity to alter host lipopolysaccharide in the lysogenic state. The viral protein responsible for O-antigen recognition is the tailspike protein. The virion contains at least six structural proteins and an approximately 40 kb dsDNA genome of known sequence. At the sequence level, the structural proteins most closely resemble the Bcep phages of Burkholderia, a human pathogen affecting cystic fibrosis patients. The virion structural proteins and chromosome together make a particle with a mass of approximately 66 Megadaltons and a diameter of roughly 650¿. Jon King's lab has used mass spectrometric methods to identify those open reading frames encoding virion structural proteins. The structure of this virus will reveal the arrangement of structural proteins and, in particular, the configuration of those subunits more directly involved in attachment to the host and passage of DNA into the cytoplasm. A genetic approach is now underway to isolate amber mutants in virus structural proteins. Macromolecular subassemblies formed during infections with these mutant phage will be purified and imaged by reconstruction. These mutant phage will also serve as reagents for imaging the interactions between virus and lipopolysaccharide and receptor proteins at the surface of the host.