CAREER: Programming Microbial Extracellular Electron Flux

微生物在细胞外电子转移（EET）过程中将电子穿梭进出细胞。微生物通过细胞外电子转移来感知它们的环境。如果连接到电极上，这些生物也可以产生电流。利用微生物电流的一个主要挑战是无法精确控制细胞外电子转移。该项目的重点是开发一个遗传工具包，将允许细胞外电子转移活动进行编程。在计算机编程中，像“与”和“或”这样的逻辑操作可以与其他操作组合以创建一组指令。执行调节功能的遗传元件可以模仿逻辑操作来创建。本计画将开发这些元件，并将它们联合收割机来规划细胞外电子传递系统的行为。该项目将包括一个教育和推广计划，通过创建一个新生研究计划，扩大学生获得基于项目的学习。这些努力将有助于培养高技能的STEM劳动力。细胞外电子转移对微生物催化和生物制造具有重要意义。解锁这些应用程序将需要严格的遗传控制细胞外电子传递通量。为了应对这一挑战，本研究项目的主要目标是通过优化模型电活性细菌Shewanella oneidensis中关键细胞外电子传递蛋白的表达来编程细胞外电子传递通量。为了实现这一目标，项目研究人员将追求几个主要目标。 第一个目标将是开发启动子/核糖体结合位点库，这些位点将驱动特异性细胞外电子转移蛋白的产生。另一个目标将是设计遗传逻辑门，将响应外部施加的信号。 总的来说，这些结果将为细胞外电子转移提供基本的见解。这一成果反过来将确立希瓦氏菌作为生物制造、生物能源和生物传感应用的潜在变革性有机体。该奖项反映了NSF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。

Microbes shuttle electrons into and out of their cells in a process called extracellular electron transfer (EET). Microbes sense their environment using extracellular electron transfer. If connected to an electrode, these organisms could also generate electrical currents. One major challenge to harnessing electrical currents from microbes is the inability to precisely control extracellular electron transfer. This project is focused on developing a genetic toolkit that would allow extracellular electron transfer activity to be programmed. In computer programming, logical operations like "AND" and "OR" can be combined with other operations to create a set of instructions. Genetic elements that perform regulatory functions can be created that mimic logical operations. This project will develop those elements and combine them to program the behavior of the extracellular electron transfer system. This project will include an education and outreach program that expands student access to project-based learning through the creation of a freshman research program. These efforts will contribute to the development of a highly skilled STEM workforce.Extracellular electron transfer has implications for microbial catalysis and biomanufacturing. Unlocking these applications will require strict genetic control over extracellular electron transfer flux. To address this challenge, the primary goal of this research project is to program extracellular electron transfer flux through the optimized expression of critical extracellular electron transfer proteins in the model electroactive bacterium, Shewanella oneidensis. To accomplish this objective, the project researchers will pursue several major objectives. The first goal will be to develop libraries of promoter/ribosome binding sites that will drive the production of specific extracellular electron transfer proteins. Another aim will be to design genetic logic gates that will respond to externally applied signals. Overall, the results will provide fundamental insights into extracellular electron transfer. This outcome, in turn, will establish Shewanella oneidensis as a potentially transformative organism for biomanufacturing, bioenergy, and biosensing applications.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.