CAREER: Electrochemically Active Biofilms

职业：电化学活性生物膜（ECABs）是指微生物通过电极的直接电化学刺激而生长，而不是暴露在作为电子供体和受体的化学物质中，被广泛应用于生物修复、废水处理、生物燃料和生化生产、微生物燃料电池、腐蚀研究和传感器开发。然而，人们对生物膜细胞和固体电极之间的电子转移过程知之甚少。本研究量化氧化还原介导的电子转移速率，目的是确定如何刺激或（取决于应用）限制电化学诱导的细胞生长速率和/或产物形成的基本科学理解。这项工作还将创建一个定量的、基于机制的数学模型，该模型可用于预测生物膜细胞生长和产物形成的速率，使用电化学、扩散反应和基于基因组尺度的约束模型来预测电子转移速率及其对微生物代谢过程的影响。研究将涉及三种模式生物的实验：硫还原菌、活动单胞菌和鲍曼不动杆菌。实验将在平板反应器和定深膜式发酵罐中进行。关键的水相特性和电子转移速率将使用创新的伏安技术、可以测量局部化学的微传感器和生物膜的电化学活性来测量。生物膜结构将通过共聚焦扫描激光显微镜检查。这项工作的广泛影响是深远的，包括与微生物燃料电池、生物燃料、生物修复和生物医学应用相关的潜在社会和经济影响。该项目将产生第一个预测电子传递速率及其与微生物代谢反应的相关性的数学模型，该模型可用于预测代谢反应和细胞生长和生物膜生成速率。此外，该项目还展示了教育与研究的紧密结合，包括为大学本科生和高中生创建一个新颖的、动手操作的微生物燃料电池教育模块。来自爱达荷州和华盛顿州西班牙裔和印第安人入学率较高的学校的高中教师和学生将参与该项目，试图扩大少数族裔学生在STEM领域的参与。

Beyenal, Haluk Washington State UniversityCAREER:Electrochemically Active Biofilms0954186Electrochemically active biofilms (ECABs) where microorganisms are grown through the direct electrochemical stimulation via electrodes, as opposed to being exposed to chemicals that serve as electron donors and acceptors, are widely used in bioremediation, wastewater treatment, biofuel and biochemical production, microbial fuel cells, corrosion studies, and in sensor development. The electron transfer processes between biofilm cells and the solid electrodes, however, are poorly understood. This research quantifies redox-mediated electron transfer rates with the goal of determining fundamental scientific understandings of how to stimulate or, depending on the application, limit electrochemically-induced cell growth rates and/or product formation. The work will also create a quantitative, mechanism-based, mathematical model that can be used to predict rates of biofilm cell growth and product formation using electrochemical, diffusion-reaction, and genome-scale constraint-based models to predict electron transfer rates and their impact on microbial metabolic processes. Research will involve experiments with three model organisms: Geobactor sulfurreducens, Zymonmonas mobilis, and Acinetoobater baumanii. Experiments will be carried out in flat-plate reactors and constant-depth film fermentors. Critical aqueous phase characteristics and electron transfer rates will be measured using innovative voltammetric techniques, microsensors that can measure local chemistry, and the electrochemical activities of the biofilms. Biofilm structure will be examined via confocal scanning laser microscopy. Broader impacts of the work are far-reaching and include potential societal and economic implications related to microbial fuel cells, biofuels, bioremediation, and biomedical applications. The project will produce the first mathematical model for predicting electron transfer rates and their correlation to microbial metabolic reactions, which can be used to predict metabolic reactions and cell growth and biofilm production rates. In addition, the project demonstrates the strong integration of education and research that includes creation of a novel, hands-on, microbial fuel cell education module for college undergraduates and another for high school students. High school teachers and students from schools in Idaho and Washington State with high Hispanic and Native American enrollments will be engaged in the project to try and broaden participation of minority students in STEM fields.