Wu Xian, Yang Guiqin, Guo Junhui, Zhuang Li
Guangdong Key Laboratory of Environmental Pollution and Health, College of Environment and Climate, Jinan University, Guangzhou 511443, China.
Guangdong Key Laboratory of Environmental Pollution and Health, College of Environment and Climate, Jinan University, Guangzhou 511443, China.
Bioelectrochemistry. 2025 Feb;161:108836. doi: 10.1016/j.bioelechem.2024.108836. Epub 2024 Oct 15.
The core of bioelectrochemical systems (BESs) is electrochemically active microorganisms (EAMs), which exert spatial heterogeneity on electrode surface and influences BESs performance. Setting an optimal potential is an effective strategy for improving and optimizing BESs performance, however, how the electrode potential affects spatial structure of microbial community within anode biofilm is not known. Using a complex substrate-fed BES with a wastewater inoculum, this study investigated the community structure and composition of the stratified biofilm developed under the potential of -0.3 V, 0 V, +0.3 V and +0.6 V (vs. saturated calomel electrode) by freezing microtome method and high-throughput sequencing analysis. The spatial heterogeneity of biofilm community was found to be dependent on the electrode potential and a less stratified community structure was observed for +0.6 V than other potentials. Within the biofilms, the inner layers selected more Geobacter and the outer layers enriched more Acinetobacter and Serratia, potentially suggested a stratification of electron transfer pathway and metabolite-based interspecies communications. The results demonstrated the response of spatial heterogeneity of anode biofilm community to the change of electrode potential, which helps to understand the selectivity and enrichment of kinetically efficient anodic microbiome by electron potential.
生物电化学系统（BESs）的核心是具有电化学活性的微生物（EAMs），它们在电极表面产生空间异质性并影响BESs的性能。设定最佳电位是改善和优化BESs性能的有效策略，然而，电极电位如何影响阳极生物膜内微生物群落的空间结构尚不清楚。本研究使用接种了废水的复杂底物进料BES，通过冷冻切片法和高通量测序分析，研究了在-0.3 V、0 V、+0.3 V和+0.6 V（相对于饱和甘汞电极）电位下形成的分层生物膜的群落结构和组成。发现生物膜群落的空间异质性取决于电极电位，并且与其他电位相比，在+0.6 V时观察到的群落结构分层较少。在生物膜内，内层选择了更多的地杆菌，外层富集了更多的不动杆菌和沙雷氏菌，这可能表明电子传递途径和基于代谢物的种间通讯存在分层现象。结果证明了阳极生物膜群落空间异质性对电极电位变化的响应，这有助于理解电子电位对动力学高效阳极微生物群落的选择性和富集作用。
