Multi-Omics Analysis Reveals the Nitrogen Removal Mechanism Induced by Electron Flow during the Start-up of the Anammox-Centered Process

TY - JOUR

T1 - Multi-Omics Analysis Reveals the Nitrogen Removal Mechanism Induced by Electron Flow during the Start-up of the Anammox-Centered Process

AU - Zhang, Li

AU - Hao, Shiwei

AU - Dou, Quanhao

AU - Dong, Tingjun

AU - Qi, Wei Kang

AU - Huang, Xiaowu

AU - Peng, Yongzhen

AU - Yang, Jiachun

PY - 2022/10/10

Y1 - 2022/10/10

N2 - Significant progress in understanding the key enzymes or species of anammox has been made; however, the nitrogen removal mechanism in complex coupling systems centered on anammox remains limited. In this study, by the combination of metagenomics–metatranscriptomics analyses, the nitrogen removal in the anammox-centered coupling system that entails partial denitrification (PD) and hydrolytic acidification (HA, A-PDHA) was elucidated to be the nitrogen transformation driven by the electron generation–transport–consumption process. The results showed that a total nitrogen (TN) removal efficiency of >98%, with a TN effluence of 98%, was achieved after 59 days under famine operation and alkaline conditions during the start-up process. Further investigation confirmed that famine operation promoted the activity of genes responsible for electron generation in anammox, and increased the abundance or expression of genes related to electron consumption. Alkaline conditions enhanced the electron generation for PD by upregulating the activity of glyceraldehyde 3-phosphate dehydrogenase and strengthened electron transfer by increasing the gene encoding quinone pool. Altogether, these variations in the electron flow led to efficient nitrogen removal. These results improve our understanding of the nitrogen removal mechanism and application of the anammox-centered coupling systems in treating nitrogen wastewater.

AB - Significant progress in understanding the key enzymes or species of anammox has been made; however, the nitrogen removal mechanism in complex coupling systems centered on anammox remains limited. In this study, by the combination of metagenomics–metatranscriptomics analyses, the nitrogen removal in the anammox-centered coupling system that entails partial denitrification (PD) and hydrolytic acidification (HA, A-PDHA) was elucidated to be the nitrogen transformation driven by the electron generation–transport–consumption process. The results showed that a total nitrogen (TN) removal efficiency of >98%, with a TN effluence of 98%, was achieved after 59 days under famine operation and alkaline conditions during the start-up process. Further investigation confirmed that famine operation promoted the activity of genes responsible for electron generation in anammox, and increased the abundance or expression of genes related to electron consumption. Alkaline conditions enhanced the electron generation for PD by upregulating the activity of glyceraldehyde 3-phosphate dehydrogenase and strengthened electron transfer by increasing the gene encoding quinone pool. Altogether, these variations in the electron flow led to efficient nitrogen removal. These results improve our understanding of the nitrogen removal mechanism and application of the anammox-centered coupling systems in treating nitrogen wastewater.

KW - anammox

KW - hydrolytic acidification

KW - partial denitrification

KW - metagenomic sequencing

KW - metatranscriptomic sequencing

U2 - 10.1021/acs.est.2c02181

DO - 10.1021/acs.est.2c02181

M3 - 文章

C2 - 36215419

SN - 0013-936X

JO - Environmental Science & Technology

JF - Environmental Science & Technology

ER -