微生物胞外长距离电子传递网络研究进展

Research progress in microbial extracellular long-distance electron transport networks

摘要:

微生物的电子传递过程在生命进化和生物地球化学循环中发挥着关键作用。近年来，随着微生物电子传递研究的深入开展，微生物纳米导线、导电生物被膜及种间电子传递等多种新型的微生物胞外电子传递机制不断被发现，微生物电子传递的距离也从纳米级拓展至厘米级。这些微生物的长距离电子传递过程环环相扣、相互协同，从而构成长距离电子传递网络，并在物质循环和能量转化中共同发挥作用。微生物长距离电子传递网络的结构功能及其调控机制已成为多个学科共同关注的焦点。本文以电子传递的距离为主线，对不同尺度的微生物长距离电子传递过程及网络研究的新进展进行综述，包括纳米尺度的电子传递网络（周质空间和外膜表层）、微米至毫米尺度的电子传递网络（纳米导线、细胞间电子和导电生物被膜）、厘米尺度的电子传递网络（电缆细菌）等，并分析了该研究现存的主要问题和下一步的发展方向，以期为进一步推进微生物长距离电子传递网络理论和应用研究提供科学参考。

Abstract:

Microbial electron transfer processes play a key role in both life evolution and biogeochemical cycles of various elements. In recent years, toward a deeper understanding of the microbial electron transfer, many novel microbial extracellular electron transfer strategies have been discovered, such as microbial nanowires, electrically conductive biofilms, interspecies electron transfer. Meanwhile, the electron transport distance increases from nanometer scale to centimeter scale. Generally, these long-distance microbial electron transport processes interacted and connected to each other, and form microbial electron transfer networks which play key roles in substance and energy transformations. The mechanisms and functions of microbial long-distance electron transport have been paid increasing attentions from different disciplines. Along the scale of electron transfer distance, this review introduces recent progresses in microbial long distance electron transport pathways and networks, including nanometer electron transport networks (cell periplasm space and outer surface), micro-to-millimeter electron transport networks (nanowire, inter-cellular electron transfer and conductive biofilms), and centimeter electron transport networks (cable bacteria). The challenges, problems and future research directions in this field are also discussed for providing more information to the researchers related.