细菌的磷酸转移酶系统.ppt

第一页，共十五页，2022年，8月28日 Bacteria are thrifty cells. They often live in inhospitable environments, and many live in places with no oxygen, so their options for generating energy are limited. So, bacteria have developed many clever ways of living off of whatever is available, and exploiting these resources to their best advantage. The bacterial phosphotransferase system, often abbreviated as PTS, is a perfect example of both the opportunistic nature of bacterial life, and their thrifty use of resources. 注释： 细菌是种节俭的细胞生物体。他们通常都在恶劣的环境当中生存，甚至许多生存在没有氧气的地方，所以他们产生能量的方式选择非常有限。因此细菌自身培养了许多巧妙的方法以适应接触的任何环境，以及开发这些资源于自身以最好的利用。细菌的磷酸转移酶系统，通常缩写为PTS，无论是对细菌生活的多机会自然环境，还是他们节俭使用的资源，都是一个完美的例子。 Leading ： 第二页，共十五页，2022年，8月28日 细菌中糖的磷酸转移酶功能发现 In 1964, Kundig, Ghosh and Roseman reported the discovery of the PEP: sugar phosphotransferase system (PTS). Thirty years later, we find that the PTS functions not only as a sugar-phosphorylating system, but also as a complex protein kinase（复合蛋白激酶） system that regulates（调节） a wide variety of metabolic（新陈代谢的） processes and controls the expression of numerous（大量） genes. As a result of recent operon- and genome-sequencing projects, novel新的 PTS protein-encoding编码 genes have been discovered, most of which have yet to be functionally defined. Some of them appear to be involved in cellular细胞的 processes distinct from those recognized previously先前的. Fundamental aspects of past and current PTS research are briefly reviewed, and recent advances增长 are integrated整合 into conceptual pictures that provide guides for future research. 第三页，共十五页，2022年，8月28日 How Phosphotransferase System-Related Protein Phosphorylation Regulates Carbohydrate Metabolism（糖类新陈代谢系统） in Bacteria 第四页，共十五页，2022年，8月28日 蛋白的磷酸化及去磷酸化状态在分解物代谢阻遏中起关键作用。PTS系统是运载体家族中的转位分子，在原核生和古细菌中广泛存在。大肠杆菌主要通过PEP—sugar PTS以集团转移方式进行葡萄糖的摄取， PTS包括EI，HPr，EII。前两者为胞质可溶型蛋白，无底物识别特异性。分别由pstI，pstH操纵子编码，后者多为蛋白复合体，对碳水化合物具有识别特异性,可特异性识别和转运底物分子，E.coli编码约20种EⅡs，涉及20多种不同碳化物磷酸化转运。 第五页，共十五页，2022年，8月28日 Hpr: histidine-cont