Mechanistic Studies on a DNA Packaging Machine

DNA包装机的机理研究

• 批准号: 6655087
• 负责人: Carlos Enrique Catalano
• 金额: $ 26.8万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-10 至 2005-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6655087
• 关键词: DNA; DNA virus; adenosine triphosphate; bacteriophage lambda; endodeoxyribonuclease; genome; molecular assembly /self assembly; virus assembly; virus genetics; virus protein

DESCRIPTION (provided by the applicant): The assembly of nucleoprotein structures that perform complex biological functions is a common theme in nature. Relevant examples include the nucleoprotein complexes involved in chromosomal replication, DNA transcription, and genome "packaging" in many double-stranded DNA (dsDNA) viruses. Terminase enzymes are common to a diverse group of dsDNA viruses, including the herpesvirus groups. These enzymes are an integral part of a series of nucleoprotein complexes critical to genome packaging. All of the known terminases possess ATPase and nuclease activities that play an important role in the packaging process. The principal investigator and his group are interested in the biochemical properties of the packaging machinery, and specifically the enzymology of the terminase enzymes. Studies described in this proposal seek to understand the molecular mechanism of genome packaging by lambda terminase. The enzyme possesses site-specific nuclease and ATPase catalytic activities that work in concert to package viral DNA. Viable models describing the packaging pathway have been developed. Many aspects of the packaging pathway remain obscure, however, and most lack mechanistic rigor. Studies are designed to provide a mechanistic basis for the delicate interplay between these catalytic activities, and their role in the assembly and stability of nucleoprotein packaging intermediates. Biochemical and enzyme kinetic studies are designed to directly probe the catalytic mechanism of the enzyme, and to define the role of catalysis in nucleoprotein complex assembly and function. While mechanistic details may differ, the data derived from these experiments may be used to model DNA packaging by other double-stranded DNA viruses, including the medically relevant adenovirus and herpesvirus groups. Furthermore, this enzyme shares mechanistic similarities to the complex nucleoprotein machines involved in DNA replication and transcription. An understanding of the catalytic properties of this packaging machine may yield insight into the general mechanisms of DNA manipulation by large multiprotein enzyme complexes.

描述（由申请人提供）：核蛋白的组装 执行复杂生物功能的结构是一个共同的主题 自然。相关例子包括参与的核蛋白复合物 许多细胞中的染色体复制、DNA 转录和基因组“包装” 双链 DNA (dsDNA) 病毒。终止酶是多种酶所共有的 dsDNA 病毒组，包括疱疹病毒组。这些酶是一种 对基因组至关重要的一系列核蛋白复合物的组成部分 包装。所有已知的终止酶都具有 ATP 酶和核酸酶活性 在包装过程中发挥着重要作用。校长 研究人员和他的团队对这种物质的生化特性很感兴趣 包装机械，特别是终止酶的酶学。 该提案中描述的研究旨在了解分子机制 通过 lambda 终止酶进行基因组包装。该酶具有位点特异性 核酸酶和 ATP 酶催化活性协同作用来包装病毒 脱氧核糖核酸。描述包装途径的可行模型已经开发出来。许多 然而，包装途径的各个方面仍然模糊不清，而且大多数缺乏 机械的严谨性。研究旨在提供机制基础 这些催化活性之间微妙的相互作用及其在 核蛋白包装中间体的组装和稳定性。生化 酶动力学研究旨在直接探测催化作用 酶的机制，并定义核蛋白中的催化作用 复杂的装配和功能。虽然机械细节可能有所不同，但数据 从这些实验中得出的结果可用于其他模型的 DNA 包装建模 双链DNA病毒，包括医学相关的腺病毒和 疱疹病毒群。此外，这种酶在机制上与 参与 DNA 复制的复杂核蛋白机器 转录。了解该包装的催化特性 机器可以通过以下方式深入了解 DNA 操作的一般机制 大型多蛋白酶复合物。