Xenorhabdus Mutualsim and Pathogenesis: Temporal Regulation and Function of Symbiosis Factors

致病杆菌互生与发病机制：共生因子的时间调节和功能

• 批准号: 0950873
• 负责人: Heidi Goodrich-Blair
• 金额: $ 52.8万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-15 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0950873&HistoricalAwards=false
• 关键词: Xenorhabdus; Mutualsim; Pathogenesis; Temporal; Regulation

In symbiotic associations animals, including humans, interact with bacteria that can be either beneficial or harmful. Currently there is limited knowledge of how bacterial adaptation to different host environments dictates whether a particular microbe will cause benefit or harm, despite the important implications of such knowledge in preventing or promoting specific bacterial interactions. This research focuses on understanding how bacteria sense and respond to different host environments to initiate expression of either beneficial or harmful traits. The bacterium being studied expresses beneficial traits when it is associated with a small soil-dwelling roundworm (nematode), and expresses virulence traits when it is associated with insect larvae. As part of its natural life cycle, the nematode transmits (vectors) the bacterium into the insect larva. In this new environment, the bacterium expresses virulence traits, and kills the insect. The insect cadaver then serves as a nutrient source for reproduction and further dissemination of both the nematode and bacteria. This research will examine the complex molecular circuitries that coordinate and regulate the expression of beneficial and harmful traits as the bacteria move between different animal hosts. The paradigms revealed by this research will provide broad insights into such questions as: how does bacterial adaptation to new environments alter symbiotic behavior, and how do vector-borne disease-causing bacteria adapt during transmission by the vector? The results of this research will be published and disseminated to the public through community seminars and high school outreach programs. Undergraduate, graduate, and post-doctoral students will be trained in areas of molecular biology, nematology, entomology, and bacteriology through direct scientific inquiry. Thus, this project will provide fundamental knowledge of bacterial interactions with animal hosts, and will train future scientists with the expertise to further apply this knowledge.

在共生关系中，包括人类在内的动物与细菌的相互作用可能是有益的，也可能是有害的。目前，对于细菌对不同宿主环境的适应如何决定特定微生物是否会带来益处或危害的知识有限，尽管这些知识对于预防或促进特定细菌相互作用具有重要意义。 这项研究的重点是了解细菌如何感知和响应不同的宿主环境，以启动有益或有害特征的表达。所研究的细菌在与小型土壤蛔虫（线虫）相关时表现出有益特征，在与昆虫幼虫相关时表现出毒力特征。 作为其自然生命周期的一部分，线虫将细菌传播（载体）到昆虫幼虫中。在这个新环境中，细菌表现出毒力特征并杀死昆虫。然后昆虫尸体作为线虫和细菌繁殖和进一步传播的营养源。这项研究将检查当细菌在不同动物宿主之间移动时协调和调节有益和有害特征表达的复杂分子电路。这项研究揭示的范式将为以下问题提供广泛的见解：细菌对新环境的适应如何改变共生行为，以及媒介传播的致病细菌在媒介传播过程中如何适应？这项研究的结果将通过社区研讨会和高中外展计划向公众发布和传播。 本科生、研究生和博士后将通过直接科学探究接受分子生物学、线虫学、昆虫学和细菌学领域的培训。 因此，该项目将提供细菌与动物宿主相互作用的基础知识，并将培训未来的科学家，使其具备进一步应用这些知识的专业知识。