| Title | Defence strategies and antibiotic resistance gene abundance in enterococci under stress by exposure to low doses of peracetic acid |
| Abstract | Peracetic acid (PAA) is an organic compound used efficiently as disinfectant in wastewater treatments. Yet, at low doses it may cause selection; thus, the effect of low doses of PAA on Enterococcus faecium as a proxy of human-related microbial waste was evaluated. Bacteria were treated with increasing doses of PAA (from 0 to 25 mg L-1 min) and incubated in regrowth experiments under non-growing, limiting conditions and under growing, favorable conditions. The changes in bacterial abundance, in bacterial phenotype (number and composition of small cell clusters), and in the abundance of an antibiotic resistance gene (ARG) was evaluated. The experiment demonstrated that the selected doses of PAA efficiently removed enterococci, and induced a long-lasting effect after PAA inactivation. The relative abundance of small clusters increased during the experiment when compared with that of the inoculum. Moreover, under growing favorable conditions the relative abundance of small clusters decreased and the number of cells per cluster increased with increasing PAA doses. A strong stability of the measured ARG was found, not showing any effect during the whole experiment. The results demonstrated the feasibility of low doses of PAA to inactivate bacteria. However, the stress induced by PAA disinfection promoted a bacterial adaptation, even if potentially without affecting the abundance of the ARG. |
| Source | Chemosphere 185, pp. 480–488 |
| Keywords | Antibiotic resistanceDisinfectionEnterococcus faeciumPeracetic acidWastewater treatment |
| Journal | Chemosphere |
| Editor | Elsevier, Oxford, Regno Unito |
| Year | 2017 |
| Type | Articolo in rivista |
| DOI | 10.1016/j.chemosphere.2017.07.032 |
| Authors | Turolla, Andrea; Sabatino, Raffaella; Sabatino, Raffaella; Fontaneto, Diego; Eckert, Ester M.; Colinas, Noemi; Corno, Gianluca; Citterio, Barbara; Biavasco, Francesca; Antonelli, Manuela; Mauro, Alessandro; Mauro, Alessandro; Mangiaterra, Gianmarco; Di Cesare, Andrea |
| Text | 374642 2017 10.1016/j.chemosphere.2017.07.032 Scopus 2 s2.0 85023617301 ISI Web of Science WOS WOS 000408597300055 Antibiotic resistance Disinfection Enterococcus faecium Peracetic acid Wastewater treatment Defence strategies and antibiotic resistance gene abundance in enterococci under stress by exposure to low doses of peracetic acid Turolla, Andrea; Sabatino, Raffaella; Sabatino, Raffaella; Fontaneto, Diego; Eckert, Ester M.; Colinas, Noemi; Corno, Gianluca; Citterio, Barbara; Biavasco, Francesca; Antonelli, Manuela; Mauro, Alessandro; Mauro, Alessandro; Mangiaterra, Gianmarco; Di Cesare, Andrea Politecnico di Milano; IRCCS Istituto Auxologico Italiano; IRCCS Istituto Auxologico Italiano; Consiglio Nazionale delle Ricerche; Universita degli Studi di Urbino Carlo Bo; Universita Politecnica delle Marche; Universita degli Studi di Torino Peracetic acid PAA is an organic compound used efficiently as disinfectant in wastewater treatments. Yet, at low doses it may cause selection; thus, the effect of low doses of PAA on Enterococcus faecium as a proxy of human related microbial waste was evaluated. Bacteria were treated with increasing doses of PAA from 0 to 25 mg L 1 min and incubated in regrowth experiments under non growing, limiting conditions and under growing, favorable conditions. The changes in bacterial abundance, in bacterial phenotype number and composition of small cell clusters , and in the abundance of an antibiotic resistance gene ARG was evaluated. The experiment demonstrated that the selected doses of PAA efficiently removed enterococci, and induced a long lasting effect after PAA inactivation. The relative abundance of small clusters increased during the experiment when compared with that of the inoculum. Moreover, under growing favorable conditions the relative abundance of small clusters decreased and the number of cells per cluster increased with increasing PAA doses. A strong stability of the measured ARG was found, not showing any effect during the whole experiment. The results demonstrated the feasibility of low doses of PAA to inactivate bacteria. However, the stress induced by PAA disinfection promoted a bacterial adaptation, even if potentially without affecting the abundance of the ARG. 185 Published version http //www.sciencedirect.com/science/article/pii/S0045653517310755 turolla 2017_Chemosph_Turolla et al.pdf Articolo in rivista Elsevier 0045 6535 Chemosphere Chemosphere Chemosphere Chemosphere. Chemosphere. Environmental chemistry, Chemosphere. Persistent organic pollutants and dioxins, Chemosphere. Environmental toxicology and risk assessment, Chemosphere. Science for Environmental toxicology, estermaria.eckert ECKERT ESTER MARIA gianluca.corno CORNO GIANLUCA diego.fontaneto FONTANETO DIEGO andrea.dicesare DI CESARE ANDREA |
