The aim of this study was to investigate the ecological role of quorum-sensing signaling molecule on the autotrophic biocathode for CO₂ reduction and acetate synthesis. As a typical quorum-sensing signaling molecule, N-Hexanoyl-L-homoserine lactone (C6HSL) was used to regulate the construction of cathode biofilm. Results showed that the maximum acetate production from CO₂ reduction improved by 94.8%, and the maximum Faraday efficiency of the microbial electrosynthesis system enhanced by 71.7%, with the regulation of C6HSL. Electrochemical analyses indicated that higher electrochemical activity and lower charge resistance of biocathode were obtained with C6HSL than without C6HSL. Confocal laser scanning microscopy and electron inhibitor experiment suggested that exogenous C6HSL increased living biomass in the biofilm and facilitated the electron transfer pathway related to NADH dehydrogenase-CoQ and proton motive force. With the C6HSL regulation, the relative abundance of hydrogen producers (e.g., Desulfovibrio and Desulfomicrobium) increased, contributing to the improved performance of autotrophic biocathode.

本研究的目的是研究群体感应信号分子对 CO ₂还原和乙酸盐合成的自养生物阴极的生态作用。作为典型的群体感应信号分子，N-己酰基-L-高丝氨酸内酯（C6HSL）被用于调节阴极生物膜的构建。结果表明，CO _{2的醋酸盐产量最大}在C6HSL的调控下，还原率提高了94.8%，微生物电合成系统的最大法拉第效率提高了71.7%。电化学分析表明，与未使用 C6HSL 相比，使用 C6HSL 的生物阴极具有更高的电化学活性和更低的充电电阻。共聚焦激光扫描显微镜和电子抑制剂实验表明，外源 C6HSL 增加了生物膜中的生物量，并促进了与 NADH 脱氢酶-CoQ 和质子动力相关的电子传递途径。随着 C6HSL 法规的实施，氢气生产者（例如，脱硫弧菌和脱硫微生物）的相对丰度增加，有助于提高自养生物阴极的性能。