SGER: Vector-Transformation System for Frankia

SGER：Frankia 载体转化系统

• 批准号: 9724800
• 负责人: Jerry Johnson
• 金额: $ 5万
• 依托单位: University of Wyoming
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 1999-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9724800&HistoricalAwards=false
• 关键词: SGER; Vector; Transformation; System; Frankia

Johnson 9724800 Biological nitrogen fixation is a key segment of the nitrogen cycle. The ability to carry out this reaction is limited to a very small number of prokaryotes. A sub-set of these have the capacity to form symbiotic relationships with higher plants to facilitate the process. Bacteria in the genus Rhizobia, gram-negative rods, are the most prominent member of this group of organisms. The genetics and biochemistry of nodulation and nitrogen fixation have been intensively investigated in Rhizobia. This is largely because of the plethora of genetic tools applicable to this group of organisms as well as their relationships with many important crop plants. Frankia are the other major bacterial contributor to symbiotic nitrogen fixation. These organisms are gram positive, filamentous bacteria that nodulate a wide variety of woody plants and shrubs. Superficially, the two types of bacteria have similar modes of operation. However, there are numerous fundamental differences which have been identified between the two systems. Because the Frankia are very slow growing and do not form symbioses with commercially important plants, our knowledge of their genetics and biochemistry is extremely meager. The lack of a vector-transformation system for these bacteria has seriously hampered attempts to understand their molecular biology. Now, the availability of Frankia promoters and the development of electroporation technology as well as highly sensitive, fluorescent DNA and protein probes makes feasible a systematic analysis of the many individual steps in both vector development and transformation that need to be done in order to allow genetic analysis of this important group of ntirogen-fixing bacteria.

Johnson 9724800 生物固氮是氮循环的关键部分。 进行该反应的能力仅限于极少数原核生物。 其中的一个子集具有与高等植物形成共生关系以促进这一过程的能力。 根瘤菌属细菌（革兰氏阴性杆菌）是该生物体中最重要的成员。 根瘤菌的结瘤和固氮的遗传学和生物化学已得到深入研究。 这主要是因为有大量的遗传工具适用于这组生物体以及它们与许多重要农作物的关系。 Frankia 是共生固氮的另一个主要贡献者。 这些生物体是革兰氏阳性丝状细菌，可在多种木本植物和灌木上结瘤。 从表面上看，这两种细菌具有相似的运作方式。 然而，这两个系统之间存在许多根本性差异。 由于弗兰奇亚生长非常缓慢，并且不与具有重要商业价值的植物形成共生，因此我们对其遗传学和生物化学的了解极其贫乏。 这些细菌缺乏载体转化系统，严重阻碍了了解其分子生物学的尝试。 现在，Frankia 启动子的出现和电穿孔技术以及高灵敏度荧光 DNA 和蛋白质探针的发展使得对载体开发和转化中许多单独步骤的系统分析成为可能，以便对这一重要的固氮细菌进行遗传分析。