Novel Pathways of Polyphosphate Synthesis

聚磷酸盐合成的新途径

• 批准号: 6545498
• 负责人: ARTHUR KORNBERG
• 金额: $ 27.65万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1978
• 资助国家: 美国
• 起止时间: 1978-09-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6545498
• 关键词: Pseudomonas aeruginosa; acid anhydride hydrolase; adenosine triphosphate; bacterial genetics; biochemical evolution; cell growth regulation; enzyme activity; enzyme induction /repression; enzyme mechanism; high energy compound; isozymes; microorganism metabolism; molecular cloning; other phosphotransferase; polyphosphates; protein localization; protein purification; tissue /cell culture

DESCRIPTION (provided by applicant): Inorganic polyphosphate (poly P) is a polymer of hundreds of phosphate residues linked by high-energy phosphoanhydride bonds found in ATP. In prebiotic evolution, poly P likely served as a precursor and catalyst in the synthesis of nucleic acids and proteins. Now, poly P is found in every cell in nature-bacteria, fungi, plants and animals. In human brain, for example, the poly P chains are about 1000 residues long and concentrated in the nuclei of several cell types. In neuron-like PC- 12 cells, poly P is dynamic with a turnover time of one hour.The purpose of this study is to gain an understanding of the biochemistry of poly P, the genetic determinants of its synthesis and utilization, and its physiologic functions, especially with regard to cellular responses to nutritional deficiencies, environmental stresses and virulence in pathogenic bacteria.The proposed research will focus on three areas: 1) Novel pathways of poly P synthesis in addition to that of poly P kinase (PPK 1) already characterized in Escherichia coli and other bacteria. A new enzyme (PPK2) discovered in Pseudomonas aeruginosa will be isolated, characterized and its gene cloned, deleted and overexpressed. The physiological roles, distribution in pro- and eukaryotic species will be explored. 2) Endopoly Pase (PPN) will be purified in its proteolytically activated state and its gene cloned, transferred and overexpressed. The basis for requirement of PPN for survival in yeast will be studied as will the use of PPN as a unique reagent in vivo and in vitro. 3) Poly P in animal cells and tissues, about which so little is now known will be investigated as we have done for bacteria.The extraordinary ubiquity and conservation of poly P and its proven regulatory roles in bacteria suggest that poly P may serve a variety of functions in human cells in relation to growth, development, aging phenomena, responses to environmental stresses and aberrations of disease.

描述（由申请人提供）： 无机聚磷酸盐（聚 P）是由数百个磷酸盐残基组成的聚合物，这些磷酸盐残基通过 ATP 中的高能磷酸酐键连接。在生命起源之前的进化过程中，聚磷很可能充当核酸和蛋白质合成的前体和催化剂。现在，聚磷存在于自然界的每一个细胞中——细菌、真菌、植物和动物。例如，在人脑中，多聚 P 链长约 1000 个残基，集中在多种细胞类型的细胞核中。在神经元样 PC-12 细胞中，聚 P 是动态的，周转时间为一小时。本研究的目的是了解聚 P 的生物化学、其合成和利用的遗传决定因素及其生理学。功能，特别是关于细胞对营养缺乏、环境压力和病原菌毒力的反应。拟议的研究将集中在三个领域：1) 除聚 P 激酶 (PPK 1) 外，聚 P 合成的新途径已经在大肠杆菌和其他细菌中进行了表征。在铜绿假单胞菌中发现的一种新酶（PPK2）将被分离、表征，并对其基因进行克隆、删除和过表达。将探讨其生理作用以及在原核和真核物种中的分布。 2) 内多酶（PPN）将在蛋白水解激活状态下进行纯化，并对其基因进行克隆、转移和过表达。将研究 PPN 在酵母中存活所需的基础，以及 PPN 作为体内和体外独特试剂的用途。 3) 动物细胞和组织中的聚磷，目前对此知之甚少，我们将像对细菌所做的那样进行研究。聚磷的普遍存在和保守性及其在细菌中已被证明的调节作用表明，聚磷可能服务于多种人体细胞与生长、发育、衰老现象、对环境压力的反应和疾病畸变相关的功能。