CAREER: The role of quorum sensing in a methane-oxidizing bacterial community

细菌群落在地球上执行许多重要的过程，从循环碳到隔离和降解污染物。然而，这些群落中的细菌如何相互作用以及它们执行这些功能的环境的分子细节仍不清楚。该项目将使用最先进的质谱学和基因组学方法来确定消耗温室气体甲烷的群落中的细菌如何使用化学信号分子相互作用，以及这些相互作用如何影响甲烷消耗的速度。研究结果将有助于了解重要细菌群落的结构和功能，以便在未来对这些过程进行建模和预测。为了提高犹他大学未被充分代表的学生在生物化学方面的职业意识，该项目将使用名为生物化学家：幕后的多元方法，与犹他大学现有的倡议相结合，并加强现有的倡议。这种方法将向未被充分代表的学生介绍生物化学研究背后的人和过程，使这一领域更具关联性，并帮助这些学生培养科学认同感和自我效能感。需氧甲烷氧化细菌群落通过在直接氧化菌和本身不氧化甲烷的细菌之间分配甲烷衍生碳来隔离这种强有力的温室气体。因此，这些有机体是碳循环的重要组成部分。然而，支配这些生态关键联合体中相互作用的分子细节仍然不清楚。许多细菌使用群体感应信号来调节细菌群落中的群体行为。虽然群体感应在许多个体物种中的作用已经被研究过，但关于它在整个群落中的作用的研究工作要少得多，这些社区类似于在自然环境中发现的那些。该项目将确定群体感应在模拟甲烷氧化细菌群落中的作用。群落中存在的群体感应信号将使用先前建立的群体感应信号识别方法进行识别，包括反向稳定同位素标记，以确定哪些社区成员可以产生这些信号。非靶向代谢组学、元基因组学和元转录组学的组合将用于识别这些信号及其在模式社区中调节的基因，并在细菌分离株和简化的合成社区中进行补充机制研究。这项工作将提供对群体感应如何管理该系统的结构和功能的机械性理解。这项工作还将表征新的群体感应信号，并将受调控的基因与其表型联系起来，这将使未来能够预测该微生物群落和其他环境重要微生物群落中的分子相互作用。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Bacterial communities perform many important processes on Earth, from cycling carbon to sequestering and degrading pollutants. However, the molecular details of how the bacteria in these communities interact with each other and their environment to perform these functions are still not understood. This project will use state-of-the-art mass spectrometry and genomic methods to determine how bacteria in a community that consumes the greenhouse gas methane interact using chemical signaling molecules, and how these interactions influence the rate of methane consumption. The research results will help in understanding the structure and function of important bacterial communities, to allow for modeling and prediction of these processes in the future. To increase career awareness in biochemistry amongst underrepresented students at the University of Utah, the project will use a multicomponent approach entitled Biochemists: Behind the Scene which integrates with and enhances existing initiatives at the University of Utah. This approach will introduce underrepresented students to the people and processes behind biochemistry research, to make this field more relatable and help these students develop a science identity and sense of self-efficacy.Aerobic methane-oxidizing bacterial communities sequester this potent greenhouse gas by distributing methane-derived carbon among direct oxidizers and bacteria that do not oxidize methane themselves. These organisms are therefore an important part of the carbon cycle. However, the molecular details that govern interactions in these ecologically critical consortia are still not understood. Many bacteria use quorum sensing signals to regulate group behaviors in bacterial communities. While the role of quorum sensing has been studied in many individual species, much less work has been done on its role in whole communities that resemble those found in natural environments. This project will determine the role of quorum sensing in a model methane-oxidizing bacterial community. Quorum sensing signals present in the community will be identified using previously established quorum sensing signal identification methodologies, including inverse stable isotopic labeling, to determine which community members can produce these signals. A combination of untargeted metabolomics, metagenomics, and metatranscriptomics will be used to identify these signals and the genes they regulate in the model community, with complementary mechanistic studies in bacterial isolates and simplified synthetic communities. This work will provide a mechanistic understanding of how quorum sensing governs the structure and function of this system. This work will also characterize new quorum sensing signals and link regulated genes to their phenotypes, which will enable future predictions of molecular interactions in this and other environmentally important microbial communities.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.