Structural and Functional studies of the Relaxosome

松弛体的结构和功能研究

• 批准号: 7109267
• 负责人: LAURA M GUOGAS
• 金额: $ 4.88万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7109267
• 关键词: Escherichia coli; X ray crystallography; bacterial DNA; bacterial genetics; bacterial proteins; crystallization; enzyme activity; helicase; intermolecular interaction; microorganism conjugation; nucleoproteins; plasmids; postdoctoral investigator; protein protein interaction; protein purification; protein structure function; structural biology

DESCRIPTION (provided by applicant): The goal of this research proposal is to determine and examine crystal structures of three "Tra" proteins that comprise the "relaxosome", a nucleoprotein complex which is responsible for the nicking and unwinding of the plasmid DNA during conjugative DNA transfer (CDT). CDT is the process by which a conjugative plasmid is transferred between bacterial cells and is therefore an important mechanism for the horizontal transfer of genetic information amongst bacterial populations. The transfer process includes the formation of a stable mating pair between donor and recipient cells, nicking and unwinding of donor plasmid DNA, and transfer into the recipient cell. This entire process is orchestrated via a host of protein-protein and DNA-protein interactions, and while most of the players involved in this process have been identified, our understanding of the interactions between these players and links between each step of CDT remain poorly defined. Structures of the "relaxosome" proteins Tral, TraY and TraM both alone and in the presence of DNA will allow us to identify structural elements which are important for contact with plasmid DNA as well as drive subsequent biochemical and biophysical experiments aimed at understanding relaxosome protein contacts.

描述（由申请人提供）： 该研究建议的目的是确定和检查包含“ slaveosom”的三种“ tra”蛋白的晶体结构，这是一种核蛋白复合物，这是一种核蛋白络合物，负责在结合DNA转移（CDT）过程中造成质粒DNA的迹象和解开。 CDT是在细菌细胞之间转移共轭质粒的过程，因此是细菌种群中遗传信息水平转移的重要机制。 转移过程包括形成供体和受体细胞之间稳定的交配对，对供体质粒DNA的刻痕和放松，并转移到受体细胞中。 这整个过程是通过大量蛋白质 - 蛋白质和DNA-蛋白质相互作用来精心策划的，尽管已经确定了参与此过程的大多数参与者，但我们对这些参与者之间的相互作用以及CDT的每个步骤之间的相互作用的理解仍然很差。 单独和存在DNA的“松弛体”蛋白质，托盘和电车的结构将使我们能够鉴定出对与质粒DNA接触至关重要的结构元素，以及随后驱动旨在了解宽松体蛋白接触的生化和生物物理实验。