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.

约翰逊9724800生物固氮是氮循环的关键环节。 进行这种反应的能力仅限于极少数的原核生物。 其中一个子集有能力与高等植物形成共生关系，以促进这一过程。 根瘤菌属中的细菌，革兰氏阴性杆菌，是这组生物体中最突出的成员。 根瘤菌固氮的遗传学和生物化学已被深入研究。 这在很大程度上是因为适用于这类生物的遗传工具过多，以及它们与许多重要作物的关系。 Frankia是共生固氮的另一个主要细菌贡献者。 这些微生物是革兰氏阳性的丝状细菌，它们寄生在各种木本植物和灌木中。 从表面上看，这两种细菌的运作模式相似。 然而，这两种制度之间存在着许多根本性的差异。 由于Frankia生长非常缓慢，并且不与商业上重要的植物形成共生关系，因此我们对它们的遗传学和生物化学的了解非常贫乏。 由于缺乏这些细菌的载体转化系统，严重阻碍了对它们分子生物学的理解。 现在，Frankia启动子的可用性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的许多单独步骤进行系统分析成为可能，这些步骤需要进行，以便对这一重要的固氮细菌群进行遗传分析。