FENGXuan,CHENNing,ZHANGXin,et al.Microscopic Response Characteristics of Aerobic Granular Sludge under Dexamethasone Stress[J].China Water & Wastewater,2023,39(19):1-10.
Microscopic Response Characteristics of Aerobic Granular Sludge under Dexamethasone Stress
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第39卷
Number:
第19期
Page:
1-10
Column:
Date of publication:
2023-10-01
- Keywords:
- aerobic granular sludge; dexamethasone; extracellular polymeric substances; proteomics; microscopic response
- Abstract:
- The physicochemical properties and microscopic changes of AGS with different particle sizes under dexamethasone stress were investigated, and the microscopic response mechanism of AGS to dexamethasone was further analyzed based on EPS and proteomics. The experimental results showed that the removal of COD, total nitrogen and total phosphorus by AGS steadily increased to 88.3%, 80.8% and 76.1%, and dexamethasone removal increased up to 55.2%. The protein and polysaccharide contents of TB-EPS were higher, while the contents in SMP-EPS and LB-EPS were relatively lower. The relative abundance of proline (Pro) in AGS with the particle size of 0.6-0.8 mm was the highest, indicating that AGS with this particle size could better resist the stress of dexamethasone, which was conducive to the stable increase of AGS particle size. Tryptophan-like protein was relatively abundant in 0.6-0.8 mm AGS, implying that the dexamethasone resistance was good. In addition, the α?helix and β-sheet structures of proteins accounted for relatively high proportion in AGS with sizes of 0.6-0.8 mm and 0.8-1 mm, suggesting the relative stability of AGS. Through the analysis of KEGG pathway, metabolic pathway played a crucial role in AGS, including energy metabolism, amino acid metabolism and lipid metabolism. The AGS with the most differential proteins were those with the size greater than 2 mm and less than 0.6 mm, indicating that the greater the difference in particle size, the greater the difference in the internal dominant microbial population, and the corresponding protein functions also presented significant differences. Furthermore, in AGS of 1-2 mm and 0.8-1 mm, the difference in proteomic characteristics was small, however, the differences in internal metabolic pathways and protein functions were significant. On the basis of PCA analysis, it was speculated that 0.8-1 mm of AGS was undergoing critical microbial population succession.
Last Update:
2023-10-01