Journal
JOURNAL OF HAZARDOUS MATERIALS
Volume 408, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.jhazmat.2020.124428
Keywords
Antibiotic resistance genes; Extracellular polymeric substances; Activated sludge; Transformation; Horizontal gene transfer
Categories
Funding
- National Natural Science Foundation of China [51738012, 51825804, 51821006, 51708533]
- Fundamental Research Funds for the Central Universities
- CAS Light of West China Program [2019 XBZG-JCTD-ZDSYS-001]
Ask authors/readers for more resources
The study found that the absolute abundances of EPS-associated ARGs were significantly higher than those of cell-free ARGs in activated sludge, and the transformation abilities of EPS-associated ARGs were also significantly higher than those of cell-free ARGs.
Antibiotic resistance has been regarded as a global concern and biological wastewater treatment plants (WWTPs) are ideal hotbeds for the emergence and propagation of antibiotic resistance genes (ARGs). Extracellular polymeric substances (EPS), one of the primary components of activated sludge, might affect the distribution of extracellular ARGs in supernatant and EPS matrix, and thus alter their uptake potential by microbial cells. Herein, the presence and significance of EPS-associated ARGs in activated sludge from four WWTPs were assessed. Seven typical ARGs (sulI, sulII, blaTEM-1, tetA, tetO, tetQ, tetW) and class I integron (intI1) in EPS-associated, cell-free, and intracellular DNA were quantified. Results show that the absolute abundances of EPS-associated, cell-free, and intracellular ARGs were 5.90 x 10(6)-6.45 x 10(9), 5.53 x 10(4)-4.58 x 10(6), and 2.68 x 10(8)-1.79 x 10(11) copies/g-volatile suspended solids, respectively. The absolute abundances of EPS-associated ARGs were 0.2-4.6 orders of magnitude higher than those of the corresponding cell-free ARGs. Considering the higher DNA contents in EPS, the transformation abilities of EPS-associated ARGs were 3.3-236.3 folds higher than those of cell-free ARGs. Therefore, EPS-associated ARGs are an important source of extracellular ARGs, and it may play a crucial role in horizontal gene transfer via transformation in WWTPs.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available