Role of a conserved gene cluster family in promoting motility behavior in proteobacteria and in mediating host interactions

集体行为是生命系统的一个共同特征，从鱼群和鸟群到细菌群。集体行为可能有助于种群的生存。然而，人们对集体行为是如何精心策划的，仍然知之甚少。细菌有助于植物、动物和人类等高等生物的功能和健康。某些细菌集体移动的能力有助于它们在宿主中的定植。该项目将研究某些细菌如何通过释放特定的化学物质来协调它们的集体运动，这些化学物质可能被种群成员用作信号。该项目还将调查这些化学物质是否对宿主定殖很重要。在这些研究中将使用细菌-海绵模型。海洋海绵是最古老的动物之一，是全世界海洋的主要组成部分。这个项目的工作将有助于培训新的科学家，因为它将涉及本科生和研究生。该项目还将包括一项重大的外联工作。具体而言，科学讲习班将设计和进行的课后计划，为学生提供6-8年级在一个主要是西班牙裔和非洲裔美国人社区旁边的伊利诺伊大学芝加哥校园。讲习班的主要目的是通过说明细菌如何成为地球生命的一个重要组成部分以及化学品如何被用作一种语言形式，使细菌能够相互交流并与高等生物交流，从而使中学生参与科学研究。关于细菌运动性和宿主相互作用，仍有许多问题有待回答。一个关键问题是哪些专门的代谢物介导这些过程以及它们如何做到这一点。细菌运动性和保守的非核糖体肽合成酶（NRPS）基因簇家族，编码可能分泌的修饰肽之间的联系被确定。NRPS基因簇家族分别在假弧菌属和假单胞菌属的α-和γ-变形菌中保守，已知它们与如海绵（假弧菌属）、植物和昆虫（假单胞菌属）等多种真核宿主建立有益和拮抗相互作用。巴西假弧菌中该基因簇的失活会损害群集和游泳运动。据推测，非核糖体肽的功能作为以前未知的信号分子，以促进运动，提高生存和使主机定植。在该项目的工作中，将整合突变，转录组学，结构，成像，相对健身和宿主定植研究，以揭示NRPS基因簇家族的作用，使用Pseudovibrio海绵相互作用作为模型。此外，还将对代表性假单胞菌属进行突变、结构和成像研究。该项目预计将阐明Proteobacteria用于协调运动和定殖真核宿主的保守机制，最终扩展单细胞生物和原核生物-真核生物相互作用的集体行为的现有知识。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

Collective behavior is a common feature of living systems, from schools of fish and flocks of birds to swarms of bacteria. Collective behavior likely contributes to the survival of the population. However, precisely how collective behavior is orchestrated remains poorly understood. Bacteria contribute to the function and health of higher organisms such as plants, animals, and humans. The ability of certain bacteria to move collectively facilitates colonization of their hosts. This project will investigate how certain bacteria coordinate their collective movement by releasing specific chemicals that are likely used as signals by the members of the population. This project will also investigate whether these chemicals are important for host colonization. A bacteria-marine sponge model will be used in these studies. Marine sponges are among the most ancient animals and are a dominant component of oceans worldwide. Work on this project will facilitate training new scientists because it will involve undergraduate and graduate students. This project will also encompass a major outreach effort. Specifically, science workshops will be designed and conducted for an after school program which serves students grades 6-8 in a predominantly Hispanic and African-American neighborhood next to the University of Illinois at Chicago campus. The main objective of the workshops will be to engage middle school students in scientific research by illustrating how bacteria are an essential part of life on Earth and how chemicals are used as a form of language that allows bacteria to communicate with each other and with higher organisms. Many questions remain to be answered regarding bacterial motility and host interaction. One key question is which specialized metabolites mediate these processes and how they do so. A link was identified between bacterial motility and a conserved nonribosomal peptide synthetase (NRPS) gene cluster family which encodes modified peptides that are likely secreted. The NRPS gene cluster family is conserved in alpha- and gamma-Proteobacteria of the Pseudovibrio and Pseudomonas genera, respectively, which are known to establish beneficial and antagonistic interactions with eukaryotic hosts as diverse as marine sponges (Pseudovibrio), plants and insects (Pseudomonas). Inactivation of this gene cluster in Pseudovibrio brasiliensis impairs swarming and swimming motility. It is hypothesized that the nonribosomal peptides function as previously unknown signaling molecules to promote motility, improving survival and enabling host colonization. During work on the project, mutational, transcriptomic, structural, imaging, relative fitness, and host colonization studies will be integrated to unravel the role of the NRPS gene cluster family using the Pseudovibrio-marine sponge interaction as a model. In addition, mutational, structural, and imaging studies will also be performed with representative Pseudomonas spp. This project is expected to shed light on the conserved mechanisms that Proteobacteria employ to coordinate motility and to colonize eukaryotic hosts, ultimately expanding current knowledge of collective behavior of single cell organisms and of prokaryote-eukaryote interactions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.