Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States.
J Am Chem Soc. 2024 Jul 24;146(29):19728-19736. doi: 10.1021/jacs.4c01288. Epub 2024 Jul 13.
Electroactive microbes that can release or take up electrons are essential components of nearly every ecological niche and are powerful tools for the development of alternative energy technologies. Small-molecule mediators are critical for this electron transfer but remain difficult to study and engineer because they perform concerted two-electron transfer in native systems but only individual, one-electron transfers in electrochemical studies. Here, we report that electrode modification with ion- and electron-conductive polymers yields biosimilar, concerted two-electron transfer from via flavin mediators. biofilms on these polymers show significantly improved per-microbe current generation and morphologies that more closely resemble native systems, setting a new paradigm for the study and optimization of these electron transfer processes. The unprecedented concerted electron transfer was found to be due to altered mediator electron transfer thermodynamics, enabling biologically relevant studies of electroactive biofilms in the lab for the first time. These important findings pave the way for a complete understanding of the ecological role of electroactive microbes and their broad application in sustainable technologies.
能够释放或吸收电子的电活性微生物是几乎每个生态位的基本组成部分，也是开发替代能源技术的有力工具。小分子介体对于这种电子转移至关重要，但由于它们在天然系统中进行协同的两电子转移，而在电化学研究中仅进行单个的一电子转移，因此仍然难以研究和设计。在这里，我们报告说，通过离子和电子导电聚合物对电极进行修饰，可以从黄素介体中产生类似生物的、协同的两电子转移。在这些聚合物上的 生物膜显示出显著改善的每微生物电流生成和更类似于天然系统的形态，为这些电子转移过程的研究和优化设定了新的范例。这种前所未有的协同电子转移是由于改变了介体电子转移热力学，从而首次能够在实验室中对电活性生物膜进行与生物学相关的研究。这些重要发现为全面了解电活性微生物的生态作用及其在可持续技术中的广泛应用铺平了道路。
