促进电活性微生物产电呼吸能力的方法研究进展

Advances in approaches for promoting electricigenic respiration of electroactive microorganisms

摘要:

产电呼吸是指电活性微生物（electroactive microorganisms，EAMs）以胞外固体电极作为电子受体的一种呼吸形式，在可再生能源利用和环境修复方面具有广阔的应用前景。能否进一步提高EAMs的产电呼吸能力是相关技术能否从实验室走向实际应用的核心，而提高产电呼吸能力的关键是加强EAMs与胞外固体电极间的电子传递能力。目前总结如何促进EAMs产电呼吸能力的综述文献极少。因此，本文从投加化学试剂、施加物理作用及改造生物基因3个方面总结了现有的促进EAMs产电呼吸能力的方法，介绍了每种方法的优势与缺陷，重点阐述了每种手段的作用机理及促进效果，并从实际应用和机理研究的角度展望了今后的研究方向。

关键词:电活性微生物;产电呼吸;生物电化学系统;电子传递途径;生物基因改造

Abstract:

Microbial electricigenic respiration is a microbial metabolism mode in which electroactive microorganisms (EAMs) degrade organics and then transfer the produced electrons to extracellular solid electrodes through the respiratory chain, while EAMs gain energy to support their own growth. Microbial electricigenic respiration has broad application prospects in renewable energy utilization and environmental remediation. How to improve the microbial electricigenic respiration performances of EAMs is at the heart of promotion of relevant techniques from lab-scale research to full-scale application, and the electron transfer between EAMs and extracellular solid electrodes plays a pivotal role in microbial electricigenic respiration. To date, there have been many reviews focusing on how to improve electrode materials, however, very few literatures summarize how to strengthen the electricigenic respiration capability of EAMs. In this review, we summarized the existing approaches for promoting the respiratory performances of EAMs from the following three aspects:the addition of chemical reagents for example surfactants and signal molecules, physical force application such as ultrasonic waves and magnetic field forces, and genetic modification for instance phenazine secretion-related gene overexpression and pilA gene heterogenous expression. Advantages and disadvantages of each method were introduced, mechanisms and effects were expatiated upon, and future research directions from the perspectives of the practical application and the mechanism research were proposed.

Key words:electroactive microorganism;electricigenic respiration;bioelectrochemical system;electron transport pathway;genetic modification