Zhu Qian, Du Yingying, Zheng Yanyan, Hu Ziyi, Liu Zikang, Hu Jingping, Hou Huijie
College of Chemistry and Chemical Engineering, Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, Hubei Normal University, Huangshi, 435002, China; School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
College of Chemistry and Chemical Engineering, Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, Hubei Normal University, Huangshi, 435002, China.
Environ Res. 2025 Feb 1;266:120604. doi: 10.1016/j.envres.2024.120604. Epub 2024 Dec 10.
Electrogenic biofilm formation has been shown to be induced by intracellular c-di-GMP signaling and extracellular quorum sensing, but their interactions have been rarely explored. This study explored the effects of quorum quenching (induced by adding acylase) on electrogenic biofilm development and its underlying mechanisms. Quorum quenching impaired the electricity generation and electroactivity of electrogenic biofilms as indicated by dye decolorization rate. It significantly decreased the proportion of typical exoelectrogen Geobacter from 62.0% to 36.5% after 90 days of operation, and enriched some other functional genera (e.g., Dysgonomonas and Sphaerochaeta) to ensure normal physiological function. Moreover, metagenomic analysis revealed that the addition of acylase weakened the potential of chemical communication, as indicated by the decrease in the abundance of genes encoding the production of AHL and c-di-GMP, and the increase in the abundance of aiiA and pvdQ genes (encoding quorum quenching) and cdgC gene (responsible for c-di-GMP breakdown). Functional contribution analysis indicated that Geobacter was a major contributor to hdtS gene (encoding AHL synthesis). These findings demonstrated that quorum quenching adversely impaired not only quorum sensing but also intracellular c-di-GMP signaling, ultimately inhibiting the development of biofilm. This work lays the foundation for regulating electrogenic biofilm development and improving the performance of microbial electrochemical system using signal communication strategy.
产电生物膜的形成已被证明是由细胞内的环二鸟苷酸（c-di-GMP）信号传导和细胞外群体感应诱导的，但其相互作用鲜有研究。本研究探讨了群体淬灭（通过添加酰基转移酶诱导）对产电生物膜发育的影响及其潜在机制。如染料脱色率所示，群体淬灭损害了产电生物膜的发电能力和电活性。运行90天后，典型的外排电子菌地杆菌属的比例从62.0%显著降至36.5%，并富集了一些其他功能菌属（如 Dysgonomonas 和 Sphaerochaeta）以确保正常生理功能。此外，宏基因组分析表明，添加酰基转移酶削弱了化学通讯的潜力，这表现为编码 AHL 和 c-di-GMP 产生的基因丰度降低，以及aiiA 和 pvdQ 基因（编码群体淬灭）和 cdgC 基因（负责 c-di-GMP 分解）的丰度增加。功能贡献分析表明，地杆菌属是 hdtS 基因（编码 AHL 合成）的主要贡献者。这些发现表明，群体淬灭不仅对群体感应产生不利影响，而且对细胞内的 c-di-GMP 信号传导也有不利影响，最终抑制了生物膜的发育。这项工作为利用信号通讯策略调控产电生物膜发育和提高微生物电化学系统性能奠定了基础。
