Key Laboratory of Water and Sediment Sciences, Ministry of Education of China , Beijing 100871, China.
College of Environmental Sciences and Engineering, Peking University , Beijing 100871, China.
Environ Sci Technol. 2018 Feb 20;52(4):2206-2216. doi: 10.1021/acs.est.7b05699. Epub 2018 Feb 9.
Acyl-homoserine lactones (AHLs)-mediated quorum sensing in bacterial communities have been extensively observed. However, the metabolic pathways regulated by AHLs in bacteria remain elusive. Here, we combined long-term reactor operation with microbiological and metabolomics analyses to explore the regulatory pathways for different AHLs in anammox consortia, which perform promising nitrogen removal for wastewater treatment. The results showed that no obvious shifts induced by exogenous AHLs occurred in the microbial community and, mainly, dosing AHLs induced changes in the metabolites. 3OC6-HSL, C6-HSL, and C8-HSL controlled the electron transport carriers that influence the bacterial activity. In contrast, only 3OC6-HSL regulated LysoPC(20:0) metabolism, which affected bacterial growth. AHLs mainly regulated the synthesis of the amino acids Ala, Val, and Glu and selectively regulated Asp and Leu to affect extracellular proteins. Simultaneously, all the AHLs regulated the ManNAc biosynthetic pathways, while OC6-HSL, OC8-HSL, and C6-HSL particularly enriched the UDP-GlcNAc pathway to promote exopolysaccharides, resulting in different aggregation levels of the anammox consortia. Our results not only provide the first metabolic insights into the means by which AHLs affect anammox consortia but also hint at potential strategies for overcoming the limitations of the long start-up period required for wastewater treatment by anammox processing.
酰基高丝氨酸内酯（AHLs）介导的细菌群体感应已被广泛观察到。然而，AHLs 在细菌中调节的代谢途径仍然难以捉摸。在这里，我们结合长期反应器运行与微生物学和代谢组学分析，探索了在 anammox 菌 群落中不同 AHLs 的调节途径，该群落对废水处理具有很有前景的脱氮作用。结果表明，外源性 AHLs 没有引起微生物群落的明显变化，主要是投加 AHLs 引起了代谢物的变化。3OC6-HSL、C6-HSL 和 C8-HSL 控制影响细菌活性的电子传递载体。相比之下，只有 3OC6-HSL 调节影响细菌生长的 LysoPC(20:0)代谢。AHLs 主要调节氨基酸 Ala、Val 和 Glu 的合成，并选择性调节 Asp 和 Leu 以影响细胞外蛋白质。同时，所有 AHLs 都调节 ManNAc 生物合成途径，而 OC6-HSL、OC8-HSL 和 C6-HSL 特别丰富 UDP-GlcNAc 途径，以促进胞外多糖的产生，导致 anammox 菌群落的不同聚集水平。我们的研究结果不仅为 AHLs 影响 anammox 菌群落的方式提供了代谢方面的见解，而且还暗示了克服 anammox 处理废水所需的长启动期限制的潜在策略。
