Elucidating the Central Pathway of Microbial Electron Transport Systems in Complex Consortia

生态系统研究：阐明复杂群落中微生物电子传递系统的核心途径知识价值：微生物执行基本的能量传递反应，驱动生态系统的变化，如有机物的降解，土壤和沉积物中的养分循环。目前，人们对各种微生物群落中进行能量转移反应的生物过程的促进和调节知之甚少。微生物的能量代谢是由电子转移决定的，即呼吸或发酵不同化合物的过程。？细胞外?电子转移（EET）是微生物在呼吸或从固体化合物（如铁（III）氧化物）中获取能量时采用的一种策略，这种化合物在大多数自然环境中非常普遍。了解驱动许多生物过程的微生物EET反应将有助于开发新的方法来应对一些环境挑战，包括污染场地的生物修复、废水处理和减少农业和工业环境中的甲烷排放。微生物燃料电池（MFC）电极可以作为环境固相电子受体的类似物，因此是分离可以执行EET的生物膜（附着在表面的细菌群落）的理想系统；以及控制EET反应。该项目将利用MFC系统分离系统发育多样性，电性，微生物联合体，并将应用宏基因组学和亚转录组学分析来表征这些生物膜中的基因表达。这些数据将用于鉴定与不同环境和不同MFC操作条件下形成的生物膜相关的常见基因。由此产生的基因表达数据将提供对不同微生物群体中EET反应重要的特定基因和途径的见解。研究结果将用于创建新的遗传标记，从而能够实时调查自然环境中的EET反应。最终，这个项目的结果将产生关于电子转移过程及其与生态系统动力学的关系的基本知识。更广泛的影响：本研究通过以下方式产生更广泛的影响：1)在“电微生物学”跨学科领域发展博士后研究项目；2)在科学会议上提供博士后主持会议的机会；3)通过暑期实习项目促进本科教育和实验室经验，这些项目将涉及从先进微生物培养技术到综合基因表达分析的主题。博士后将有机会在电化学、微生物生理学和生态学、宏基因组和亚转录组学分析等领域开展跨学科研究；并将以独特的专业知识出现，可以应用于许多研究领域。

Ecosystem Research: Elucidating the Central Pathway of Microbial Electron Transport Systems in Complex ConsortiaIntellectual Merit: Microbes perform fundamental energy transfer reactions that drive ecosystem changes such as the degradation of organic matter, and nutrient cycling in soils and sediments. Presently, little is known about what biological processes are facilitated and regulated within diverse microbial communities that perform energy transfer reactions. Microbial energy metabolism is dictated by electron transfer, i.e. the process of respiring or fermenting different chemical compounds. ?Extracellular? electron transfer (EET) is a strategy that microbes employ when they are respiring or deriving energy from a solid-phase compound, like iron(III)-oxides, which are extremely prevalent in most natural environments. Understanding the microbial EET reactions that drive many biological processes will contribute to the development of new methods for dealing with several environmental challenges including bioremediation of contaminated sites, treating wastewater, and reducing methane emissions from agricultural and industrial settings.Microbial fuel cell (MFC) electrodes can act as analogs to environmental solid-phase electron acceptors and are therefore ideal systems for isolating biofilms (bacterial communities attached to surfaces) that can perform EET; and for controlling EET reactions. This project will utilize MFC systems to isolate phylogenetically diverse, electrogenic, microbial consortia and will apply metagenomic and metatranscriptomic analyses to characterize gene expression in these biofilms. These data will be used to identify common genes associated with biofilms formed from different environments and under different MFC operating conditions. The resulting gene expression data will provide insights into the specific genes and pathways that are important for EET reactions in diverse microbial consortia. The research results will be applied toward creating new genetic markers that will enable the real-time investigation of EET reactions within natural environments. Ultimately, results from this project will generate fundamental knowledge about electron transfer processes and how they relate to ecosystem dynamics. Broader impacts: The research contributes to a broader impact by: 1) developing post-doctoral research programs in the interdisciplinary field of ?Electromicrobiology?; 2) providing opportunities for post-doctoral led sessions at scientific meetings; and 3) facilitating undergraduate education and laboratory experience via summer internship programs that will address topics ranging from advanced microbial cultivation techniques to comprehensive gene expression analyses. Post-doctoral appointees will have the opportunity to conduct interdisciplinary work in fields such as electrochemistry, microbial physiology and ecology, and metagenomic and metatranscriptomic analyses; and will emerge with unique expertise that can be applied in many research areas.