MIM: Microbial Division of Labor in Polysaccharide-Degrading Communities

MIM：多糖降解群落中的微生物分工

• 批准号: 2125155
• 负责人: Stephen Lindemann
• 金额: $ 239.66万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2026-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2125155&HistoricalAwards=false
• 关键词: MIM; Microbial; Division; Labor; Polysaccharide

Microbial ecosystems called ‘microbiomes’ colonize all environments on Earth. Microbiomes play crucial roles in important environmental processes such as nutrient cycling and stress resistance. In these ecosystems, microbes compete strongly for easy-to-consume simple foods like sugars, which are rapidly consumed. Therefore, microbial communities in nature typically survive on more complex food sources like polysaccharides. In competition for a simple sugar molecule, one microbe will eventually win and the losers will go extinct. In contrast to simple sugars, polysaccharides typically require many different enzymes for complete degradation because of their complex structure. This provides opportunity for microbes to divide the labor of degradation amongst themselves with each microorganism specializing in a few tasks. Thus, microbial degradation of polysaccharides can allow diverse species to coexist. The goal of this project is to uncover the rules of life that govern how microbes divide labor when degrading complex polysaccharide molecules. To do so, the role each microorganism plays in polysaccharide degradation will be measured in natural and synthetic microbial communities. A computational model will be developed and used to predict how members divide labor. Further experiments will test these model predictions for validation. Successful completion of this research will yield new understanding of the rules by which division of labor sustains microbial diversity. Such information will have broad benefits by facilitating the engineering of microbial bioprocesses and controlling natural microbiomes. In addition, this project will help develop the next generation microbiome workforce by providing training in advanced techniques for measurement and modeling of microbial behavior. Further benefits to society will arise from public outreach designed to boost awareness of microbial ecology and teach microbial ecology concepts to K-12 students. The goal of this project is to uncover the ecological rules governing how complex substrate structure influences microbial diversity and community function through division of labor (DOL). This project tests the hypothesis that polysaccharide substrate molecular complexity sustains functionally degenerate microbial diversity through diverse transport strategies and alternate gene regulatory patterns. Together, diversity and gene regulation result in distinct hierarchies of preferred polysaccharide structures and degradation products. These mechanisms are further hypothesized to result in DOL among members that allows niche partitioning of microorganisms that degrade specific molecular structures, thereby minimizing competition. Specific research objectives to achieve the project goals are to: i) define the niches of polysaccharide-degrading microbial communities and the overall impact on community productivity and C and N flow; ii) develop genome-scale metabolic network models of polysaccharide-degrading communities and propose a theoretical framework that decomposes microbial interactions into basic DOL units; and iii) determine how DOL plays a key role in linking diversity to community productivity and stability. Successful completion of this research will uncover mechanisms by which microbes divide labor in communities consuming complex substrates and translate that mechanistic knowledge into theory that describes how microbial DOL interactions maintain diversity and influence emergent properties. Broader benefits to society result from advancing synthetic ecology strategies for the engineering of microbial consortia with applications in diverse fields ranging from remediation, bioprocessing, and ecosystem sciences. Additional benefits result from efforts to help build a microbiome workforce via project-based course development, public outreach, training workshops, and development of instructional tools for K-12 audiences. This project is supported by co-funding from the CHE Chemistry of Life Processes program in the Math and Physical Sciences Directorate and the CBET Environmental Engineering program in the Engineering Directorate.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.

被称为“微生物组”的微生物生态系统遍布地球上的所有环境。微生物群在营养循环和抗逆性等重要环境过程中起着至关重要的作用。在这些生态系统中，微生物激烈竞争容易消耗的简单食物，如糖，这些食物被迅速消耗。因此，自然界中的微生物群落通常依靠更复杂的食物来源（如多糖）生存。在争夺一个简单糖分子的竞争中，一种微生物最终会获胜，而失败者将会灭绝。与单糖相比，多糖由于其复杂的结构，通常需要许多不同的酶才能完全降解。这为微生物提供了机会，使它们能够分工降解的工作，每个微生物专门从事一些任务。因此，微生物对多糖的降解可以使不同的菌种共存。该项目的目标是揭示微生物在降解复杂多糖分子时如何分工的生命规则。为此，将在天然和合成微生物群落中测量每种微生物在多糖降解中所起的作用。将开发一个计算模型，并用于预测成员如何分工。进一步的实验将测试这些模型预测的有效性。这项研究的成功完成将产生新的理解的规则，分工维持微生物的多样性。这些信息将通过促进微生物生物过程的工程和控制天然微生物组而具有广泛的益处。此外，该项目将通过提供微生物行为测量和建模的先进技术培训，帮助开发下一代微生物组工作人员。进一步的社会效益将来自旨在提高微生物生态学意识和向K-12学生教授微生物生态学概念的公共宣传。该项目的目标是揭示复杂底物结构如何通过劳动分工（DOL）影响微生物多样性和群落功能的生态规则。本项目验证了多糖底物分子复杂性通过不同的转运策略和不同的基因调控模式维持功能退化微生物多样性的假设。总之，多样性和基因调控导致了多糖结构和降解产物的不同层次。这些机制进一步假设导致成员之间的DOL，允许微生物的生态位分配，降解特定的分子结构，从而最大限度地减少竞争。实现项目目标的具体研究目标是：i)确定多糖降解微生物群落的生态位及其对群落生产力和碳氮流的总体影响；ii)建立多糖降解群落的基因组尺度代谢网络模型，并提出将微生物相互作用分解为基本DOL单元的理论框架；iii)确定DOL如何在将多样性与社区生产力和稳定性联系起来方面发挥关键作用。这项研究的成功完成将揭示微生物在消耗复杂基质的群落中分工的机制，并将该机制知识转化为描述微生物DOL相互作用如何维持多样性和影响涌现特性的理论。在修复、生物处理和生态系统科学等不同领域的应用中，推进微生物群落工程的合成生态学策略将为社会带来更广泛的利益。通过基于项目的课程开发、公共宣传、培训研讨会和开发面向K-12受众的教学工具，帮助建立微生物组工作队伍的努力也带来了额外的好处。该项目由数学和物理科学理事会的生命过程化学项目和工程理事会的CBET环境工程项目共同资助。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。