RPG: Microbial Virulence Induction Enhancement by Plant CellWall Oligiosaccharides

RPG：植物细胞壁寡糖增强微生物毒力诱导

• 批准号: 9306507
• 负责人: Ann L. Powell
• 金额: $ 1.8万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-07-01 至 1994-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9306507&HistoricalAwards=false
• 关键词: RPG; Microbial; Virulence; Induction; Enhancement

This is a research planning grant for women. To be able to understand functions in pathogens and plants so that plant diseases can be controlled and cellular mechanisms for signal recognition between organisms can be deciphered, we will investigate enhancement of bacterial virulence functions by oligosaccharides. This enhancement will serve as a model system supporting further pursuit of virulence functions in fungi. Previous work has shown that plant cell walls contain a polygalacturonase inhibitor protein (PGIP) that recognizes and inhibits fungal polygalacturonases (PG) and that the association of PG and PGIP results in reduced breakdown of pectin so that oligosaccharides three to twenty units long are formed. These oligosaccharides have been shown to be inducers of defense responses in the plant cells and in Agrobacteria similar oligosaccharides have been suggested to be potent enhancers of virulence induction by plant phenolics. This research assesses the inhibition of bacterial PGs by pear and tomato PGIPs and determines the susceptibility to Agrobacteria infection of transgenic tomato plants expressing elevated amounts of PGIP. Furthermore, oligosaccharides optional for the enhancement of bacterialvirulence gene expression will be identified. The results from the studies outlined in this grant will provide the basis for the search in fungi for homologues to bacterial genes responsible for the regulation of virulence induction and enhancement. To be able to understand the signals that are exchanged between a microbial pathogen and a plant cell during infection, we will analyze the effect that sugar polymers have on the functions in a bacteria that allow it to infect the plant cells. These sugar polymers are known to be formed when a protein in the wall of the plant cell, PGIP, encounters an enzyme, PG, that fungi deploy in order to reach the interior of the plant cell being infected. The sugar polymers are known to trigger responses in plant cells that can slow the infection process, but they also have been suggested to enhance the infection functions in bacterial plant pathogens. Since little is known about the control of functions that fungal plant pathogenes need in order to infect plants, we will first describe the effects of the sugar polymers in the infection process by bacterial pathogens and then look for similar functions in the more complex fungal infections. We need to understand functions in both types of pathogens and in the plants in order to exercise control over plant diseases caused by these pathogens and in order to decipher basic mechanisms of communication between organisms.

这是一项针对妇女的研究规划补助金。 为了能够 了解病原体和植物的功能， 是可以控制的， 生物体之间的联系，我们将进行调查 寡糖增强细菌毒力功能。 这一增强将作为一个模型系统， 追求真菌的毒力功能。 以前的工作表明 植物细胞壁含有多聚半乳糖醛酸酶抑制蛋白 （PGIP），其识别并抑制真菌多聚半乳糖醛酸酶（PG） 并且PG和PGIP的结合导致降低 分解果胶，使低聚糖3至20个单位 长形。 这些低聚糖已被证明是 植物细胞中防御反应的诱导剂， 已经提出农杆菌类似的寡糖是 植物酚类毒性诱导的有效增强剂。 这 研究评估了梨对细菌PG的抑制作用， 番茄PGIPs和确定对农杆菌的敏感性 表达量升高的转基因番茄植物的感染 的PGIP。 此外，对于所述组合物任选的低聚糖可以是： 增强细菌毒力基因的表达， 鉴定 该资助中概述的研究结果 将为在真菌中寻找同源物提供基础， 负责调节毒力的细菌基因 诱导和增强。 为了能够理解一个人与另一个人之间交换的信号， 微生物病原体和植物细胞在感染过程中，我们将 分析糖聚合物对细胞功能的影响， 使其能够感染植物细胞。 这些糖 已知当细胞壁中的蛋白质形成聚合物时， 植物细胞PGIP遇到一种酶PG，真菌在其中部署 以便到达被感染的植物细胞内部。 的 已知糖聚合物在植物细胞中引发反应， 可以减缓感染过程，但也有人建议 以增强细菌性植物病原体的侵染功能。 由于对真菌的功能控制知之甚少， 植物病原体需要为了感染植物，我们将首先 描述糖聚合物在感染过程中的作用 然后寻找类似的功能， 更复杂的真菌感染 我们需要理解函数 这两种类型的病原体和植物，以行使 控制由这些病原体引起的植物病害， 来破译生物体之间交流的基本机制。