CAREER: The impact of spatial-positioning mechanisms on the metabolic interactions and emergent properties of synthetic bacterial communities

职业：空间定位机制对合成细菌群落代谢相互作用和新兴特性的影响

基本信息

批准号：
1749489
负责人：
James McKinlay
金额：
$ 114.9万
依托单位：
Indiana University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-01-01 至 2024-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1749489&HistoricalAwards=false
关键词：
CAREER impact spatial positioning mechanisms

项目摘要

Microbes constitute a large portion of the Earth's biomass. In the majority of environments, microbes live as interacting communities. However, not much is known regarding how microbial worlds communicate, evolve, share resources, and interact with other organisms. This project will address how bacteria position themselves within microbial communities to cooperatively trade nutrients with neighboring cells or alternatively steal nutrients from neighbors. Such cross-feeding interactions influence important processes, including human health and element cycling. Cross-feeding communities can also be harnessed to degrade pollutants and convert renewable resources into useful products, such as biofuels. The results from this project will thus have broad benefits by informing on natural microbial interactions of environmental and medical relevance and by generating principles for the engineering of bacterial communities as a technology to benefit society. This research will involve direct participation of regional high school students, including underrepresented minorities. Additional high school students will gain research experiences through a collaboration between the research team and high school teachers, which will bring experiments to classrooms. This project will also generate an innovative storytelling platform that will provide an intuitive framework upon which to communicate detail-intensive and traditionally unpopular topics in metabolism and biochemistry to learners of all ages. This project will examine how bacteria optimize their location within cross-feeding communities that pit cooperative cells against exploitive (cheater) cells. Current theory indicates that clustering of cooperative cells can keep cheaters at bay. However, this theory does not take into account mechanisms that bacteria use to sense and swim towards nutrients and to adhere to surfaces and other cells. A lack of knowledge on how motility and adhesion influence metabolic interactions and community structure hampers not only our general understanding of microbial community behavior but also our ability to design useful synthetic communities. The objective of this project is to determine the impact of motility and adhesion on subpopulation dynamics in cross-feeding communities and on emergent properties, such as hydrogen biofuel production. The objective will be achieved using both experimental and computationally-simulated communities. One community will pair ammonium-excreting cooperators and ammonium-consuming cheaters of a single species, Rhodopseudomonas palustris. A second community will pair R. palustris with Escherichia coli in an obligate cross-feeding relationship wherein ammonium from R. palustris is exchanged for carbon nutrients from E. coli. This mutualism will also be challenged with an R. palustris cheater. In each case, the effects of motility and adhesion on cooperator and cheater fitness and community structure will be determined using environmental and genetic conditions that either permit or restrict motility and adhesion. This project will thus provide a much-needed molecular understanding of spatial bacterial community behaviors of environmental, medical, and industrial relevance.

微生物构成了地球生物量的很大一部分。在大多数环境中，微生物作为互动社区生活。但是，关于微生物世界如何沟通，发展，共享资源和与其他生物体互动并不了解。该项目将解决细菌如何在微生物群落中定位，以与相邻细胞合作交易营养或从邻居那里窃取营养。这种交叉喂养相互作用会影响重要过程，包括人类健康和元素循环。交叉进食社区也可以利用以降解污染物并将可再生资源转化为有用的产品，例如生物燃料。因此，该项目的结果将通过告知环境和医学相关性的自然微生物相互作用，并通过为细菌群落的工程制定原理作为一种使社会受益的技术，从而获得广泛的好处。这项研究将涉及区域高中学生的直接参与，包括代表性不足的少数民族。额外的高中生将通过研究团队与高中教师之间的合作获得研究经验，这将为教室带来实验。该项目还将生成一个创新的讲故事平台，该平台将提供一个直观的框架，以在该框架上向所有年龄段的学习者传达新陈代谢和生物化学中的细节密集型和传统的不受欢迎的话题。该项目将研究细菌如何优化其在交叉喂养群落中的位置，以使合作细胞对抗剥削（Cheater）细胞。当前的理论表明，合作细胞的聚类可以使作弊者保持困境。但是，该理论没有考虑细菌用来感知和游泳营养和粘附在表面和其他细胞上的机制。缺乏关于运动和粘附如何影响代谢相互作用和社区结构的知识，这不仅会使我们对微生物社区行为的一般理解，而且会使我们设计有用的合成社区的能力。该项目的目的是确定运动和粘附对交叉进食社区和新兴特性（例如氢生物燃料生产）中亚种群动态的影响。使用实验和计算模拟的社区将实现该目标。一个社区将对单个物种Rhodopseudomonas Palustris的铵进行铵的合作者和占铵的作弊者。第二个社区将与大肠杆菌与大肠杆菌配对。这种互助主义也将受到R. palustris骗子的挑战。在每种情况下，都将使用允许或限制运动性和粘附的环境和遗传条件来确定运动和粘附对合作者和作弊者健身和社区结构的影响。因此，该项目将对环境，医疗和工业相关性的空间细菌社区行为提供急需的分子理解。