Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.scitotenv.2022.157318
Licence creative commons licence
Title (Primary) Cellular stress affects the fate of microbial resistance to folate inhibitors in treatment wetlands
Author Knecht, C.A.; Krüger, M.; Kellmann, S.; Mäusezahl, I.; Möder, M.; Adelowo, O.O.; Vollmers, J.; Kaster, A.-K.; Nivala, J.; Müller, J.A.
Source Titel Science of the Total Environment
Year 2022
Department UMB; UBT; ANA; UBZ
Volume 845
Page From art. 157318
Language englisch
Topic T7 Bioeconomy
T9 Healthy Planet
Keywords Antimicrobial resistance; Wastewater; Treatment wetland; Class 1 integron; Cellular stress
Abstract The environmental prevalence of antimicrobial resistance (AMR) has come into focus under the One Health concept. Wastewater treatment systems are among the significant sources of AMR in the environment. In such systems, it is uncertain to which extent antimicrobials present at sub-inhibitory concentrations constitute a selective pressure for bacterial maintenance and acquisition of antibiotic resistance (AR) genes. Here, we mapped AMR to inhibitors of folate biosynthesis in an aerated and a non-aerated horizontal subsurface flow treatment wetland receiving the same pre-treated municipal wastewater. General water characteristics and the concentrations of folate inhibitors were determined to define the ambient conditions over the longitudinal axis of the two treatment wetlands. Profiling of AMR as well as class 1 integrons, a carrier of AR genes against folate inhibitors and other antimicrobials, was conducted by cultivation-dependent and -independent methods. The wetlands achieved mean reductions of AR gene copy numbers in the effluents of at least 2 log, with the aerated system performing better. The folate inhibitors had no noticeable effect on the prevalence of respective AR genes. However, there was a transient increase of AR gene copy numbers and AR gene cassette composition in class 1 integrons in the aerated wetland. The comparison of all data from both wetlands suggests that higher levels of cellular stress in the aerated system promoted the mobility of AR genes via enhancing the activity of the DNA recombinase of the class 1 integron. The findings highlight that environmental conditions that modulate the activity of this genetic element can be more important for the fate of associated AR genes in treatment wetlands than the ambient concentration of the respective antimicrobial agents. By extrapolation, the results suggest that cellular stress also contributes to the mobility of AR gene in other wastewater treatment systems.
Persistent UFZ Identifier
Knecht, C.A., Krüger, M., Kellmann, S., Mäusezahl, I., Möder, M., Adelowo, O.O., Vollmers, J., Kaster, A.-K., Nivala, J., Müller, J.A. (2022):
Cellular stress affects the fate of microbial resistance to folate inhibitors in treatment wetlands
Sci. Total Environ. 845 , art. 157318 10.1016/j.scitotenv.2022.157318