Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China.
CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
Bioresour Technol. 2024 Nov;412:131390. doi: 10.1016/j.biortech.2024.131390. Epub 2024 Sep 1.
This study investigated the molecular mechanism behind the highly efficient performance of nitrogen-doped carbon dots (NCDs)-assisted microbial electrosynthesis systems (MESs). The impact of NCDs (C:N precursor = 1:0.5-1:3) on acetogens was examined in the biocathode. The highest electrocatalytic performance was observed with NCDs. The maximum acetate production rate of 1.9 ± 0.1 mM d was achieved in NCDsmodified MESs, which was 26.7-216.7 % higher than other MESs (0.6-1.5 mM d). With NCDs modified, the biocathode exhibited a 129.3-186.8 % increase in the abundance of Sporomusa, and 38.5-104.6 % increase in cytochrome expression (cydAB, cybH). Transcriptome confirmed that cytochromes played a crucial role in the extracellular electron uptake (EEU) of NCDs-modified Sporomusa. NCDs enhanced EEU efficiency, thereby increasing the two H-pumping steps and accelerating microbial CO fixation. These results provide valuable insights into increasing CO fixation by maximizing EEU efficiency in acetogens.
本研究探讨了氮掺杂碳点（NCDs）辅助微生物电解合成系统（MESs）高效性能背后的分子机制。在生物阴极中研究了 NCDs（C:N 前体= 1:0.5-1:3）对产乙酸菌的影响。NCDs 表现出最高的电催化性能。在 NCDs 修饰的 MESs 中，最大的乙酸盐产率达到 1.9±0.1 mM·d，比其他 MESs（0.6-1.5 mM·d）高 26.7-216.7%。用 NCDs 修饰后，生物阴极中 Sporomusa 的丰度增加了 129.3-186.8%，细胞色素表达（cydAB、cybH）增加了 38.5-104.6%。转录组证实细胞色素在 NCDs 修饰的 Sporomusa 细胞外电子摄取（EEU）中起着关键作用。NCDs 提高了 EEU 的效率，从而增加了两个 H 泵步骤，并加速了微生物 CO 固定。这些结果为通过最大化产乙酸菌的 EEU 效率来增加 CO 固定提供了有价值的见解。
