Genetics of Coronatine Biosynthesis in Pseudomonas Syringae pv. Tomato

丁香假单胞菌中冠菌素生物合成的遗传学。

• 批准号: 8902561
• 负责人: Carol Bender
• 金额: $ 11.55万
• 依托单位: Oklahoma State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-10-15 至 1993-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8902561&HistoricalAwards=false
• 关键词: Genetics; Coronatine; Biosynthesis; Pseudomonas; Syringae

The chlorosis-inducing phytotoxin coronatine has an unusual structure and consists of a polyketide component joined to an ethylcyclopropyl ring. In contrast to other phytotoxins produced by Pseudomonas syringae, coronatine is produced by multiple pathovars with distinct host specificity. Despite the importance of coronatine in the virulence of producing pathovars the genetics of coronatine biosynthesis has not been systematically studied. Transposon mutagenesis was used to generate coronatine- defective mutants of P. syringae pv. tomato. The physical analysis of these mutants suggested the involvement of a 101 kb plasmid (designated pPT23A) in coronatine synthesis. pPT23A was subsequently transferred into P. syringae pv. syringae PS61, a nonproducer of coronatine. Upon acquisition of pPT23A, PS61 gained the ability to make coronatine. Therefore, conclusive evidence has been collected for the involvement of plasmid pPT23A in production of coronatine. The experiments outlined in this proposal will precisely define the regions of pPT23A involved in coronatine biosynthesis by moleuclar cloning, mutagenesis, and complementation experiments. The results of these proposed experiments will advance knowledge in the area of phytotoxin genetics.

引起绿僵症的植物毒素冠菌素具有不寻常的 结构，并由聚酮化合物组分连接到 乙基环丙基环 与其他植物毒素相比， 由假单胞菌，冠菌素是由多个 具有明显的寄主特异性的致病变种。 尽管重要性 冠菌素的毒力产生的致病变种， 冠菌素生物合成的遗传学尚未系统地 研究了 转座子突变用于产生冠菌素- 的缺陷型突变体。番茄 物理 对这些突变体的分析表明， 质粒（命名为pPT 23 A）在冠菌素合成中的作用。 pPT 23 A是 随后转移到P. PS61，a 非冠菌素生产者。 获得pPT 23 A后，PS 61 获得了制造冠菌素的能力 因此，结论 已收集到质粒参与的证据 pPT 23 A在冠菌素生产中的应用 中概述的实验 该建议将精确地定义pPT 23 A的区域， 通过分子克隆参与冠菌素生物合成， 诱变和互补实验。的结果 这些拟议的实验将推进该领域的知识 植物毒素遗传学