Form and function of the bacterial nucleoid: structural studies using cryo-ET

项目概要/摘要： 所有生物都有一个共同的遗传密码。从哺乳动物细胞核到 作为最小的细菌，我们都使用DNA来编码驱动生命多样性的特征和细胞过程 地球上传递沿着一个人的基因组是最基本的形式遗传性和错误在这个过程中 会带来可怕的后果因此，所有生物体进行可靠的复制是非常重要的 以及细胞分裂过程中DNA的分离，以及生物体保持保护核物质的方法 在细胞压力的情况下。为了研究DNA结构的形式和功能，我建议利用 冷冻电子断层扫描（cryo-ET）方法的最新进展，以可视化细菌 类核，作为了解体内染色体结构的模型，并开发工具， 为研究细胞中最重要的分子提供了实践。利用冷冻电子的资源 显微镜研究中心在威斯康星大学麦迪逊分校，冷冻-ET的模式生物球红杆菌将 允许研究体内核结构。类球红细菌是一种理想的微生物， 类核，不仅因为它的大小适合冷冻ET，而且因为它的两条染色体需要 独特的复制动力学这项工作旨在观察类核的结构和相互作用， R. sphaeroides其结果具有提供翻译断裂的强大潜力 科学家们将建立分子工具和方法，这些工具和方法将超越细菌学。 此外，这项工作将研究细菌类核在生理应激过程中的致密化， 抗生素治疗，初步数据已经显示。重要的是，研究原子核的致密化 抗生素应激后的材料有望产生新的知识，从而更好地理解 细菌在抗生素治疗期间存活和持续存在的机制。可能影响研究 抗生素耐药性的研究

Project Summary/Abstract: All organisms share a common genetic code. From the nucleus of mammalian cells to the nucleoid of the smallest bacterium, we all use DNA to encode the traits and cellular processes that drive the diversity of life on earth. Passing along one’s genome is the most fundamental form of heritability and errors in this process can have dire consequences. It is therefore of great importance that all organisms carry out reliable replication and segregation of DNA during cell division, and that organisms maintain methods to protect nuclear material in the event of cellular stress. To study the form and function of DNA structures, I propose taking advantage of the recent advancements in cryoelectron tomography (cryo-ET) methodology to visualize the bacterial nucleoid, as a model for understanding in vivo chromosome structure and to develop the tools and best practices for the study of the cells most important molecule. Using the resources of the Cryoelectron Microscopy Research Center at UW-Madison, cryo-ET of the model organism Rhodobacter sphaeroides will allow the study of in vivo nuclear structures. Rhodobacter sphaeroides is an ideal organism for studying the nucleoid, not only because its size is amenable to cryo-ET, but also because its two chromosomes require unique replication dynamics. This work seeks to observe the structure and interactions of the nucleoid during the cell cycle of R. sphaeroides. The results of which have a strong potential to provide translational break throughs and will build up molecular tools and methods that will have relevance beyond bacteriology. Additionally, this work will study the compaction of the bacterial nucleoid during physiological stress and antibiotic treatments, preliminary data have been shown. Importantly, studying the compaction of nuclear material following antibiotic stress is expected to generate new knowledge leading to a better understanding of the mechanisms bacteria use to survive and persist during antibiotic treatment. Potentially impacting the study on antibiotic resistance.