Metagenomic and extracellular polymeric substances analysis reveals the mechanism of exogenous N-hexanoyl-L-homoserine lactone in alleviating the inhibition of perfluorooctanoic acid on anammox process

作者：Tang, Linqin; Su, Chengyuan^*; Fan, Cuiping; Cao, Linlin; Liang, Zhu; Xu, Yufeng; Chen, Zhengpeng; Wang, Qing; Chen, Menglin

来源：Bioresource Technology, 2023, 369: 128482.

DOI：10.1016/j.biortech.2022.128482

• Anammox
• N-hexanoyl-L-homoserine lactone
• PFOA
• Candidatus Kuenenia stuttgartiensis
• Metagenomic sequencing
• Anammox

To alleviate the negative effects of perfluorooctanoic acid (PFOA) on nitrogen removal via anaerobic ammonia oxidation (anammox), an exogenous signaling factor (N-hexanoyl-L-homoserine lactone, C6-HSL) was introduced into an anammox reactor. Results showed that 2 mu mol/L C6-HSL promoted the nitrogen removal efficiency of the anammox reactor under PFOA stress, with the removal efficiencies of ammonia and nitrite increasing from 79.7 +/- 4.8 % and 80.8 +/- 3.8 %, to 94.4 +/- 4.3 % and 97.1 +/- 3.8 %. Exogenous C6-HSL enhanced the compactness of the extracellular proteins, and improved the sludge hydrophobicity. Meanwhile, C6-HSL resulted in a microbial shift, with the relative abundance of Planctomycetes increasing from 30.2 % to 49.5 %. Candidatus Kuenenia stuttgartiensis replaced Candidatus Brocadia sp. BL1 as the dominant species, while the available space for other nitrogen-removing bacteria was reduced. Exogenous C6-HSL promoted the expression of anammox-related genes, such as hzsB and hdh, while denitrifying genes were down-regulated. In addition, the relative abundance of HdtS, which synthesizes AHLs, increased by 0.02446%.

• 单位
  桂林理工大学