Abstract
Bacteriophages active against a New Delhi metallo beta lactamase (NDM)-positive E. coli PI-7 were isolated from municipal wastewater and tested for their lytic effect against the bacterial host. Bacteriophages were highly specific to E. coli PI-7 when tested for host-range. After determining host-specificity, bacteriophages were tested for their ability to sensitize E. coli PI-7 to solar irradiation. Solar irradiation coupled with bacteriophages successfully reduced the length of the lag-phase for E. coli PI-7 from 4 h to 2 h in buffer solution. The reduction of lag-phase length was also observed in filtered wastewater effluent and chlorinated effluent. Previously, we found through gene expression analysis that cell wall, oxidative stress, and DNA repair functions played a large role in protecting E. coli PI-7 against solar damage. Here, gene expression analysis of bacteriophage-supplemented solar-irradiated E. coli PI-7 revealed downregulation of cell wall functions. Downregulation of functions implicated in scavenging and detoxifying reactive oxygen species, as well as DNA repair genes, was also observed in bacteriophage-supplemented solar-irradiated E. coli PI-7. Moreover, solar irradiation activates recA, which can induce lytic activity of bacteriophages. Overall, the combined treatment led to gene responses that appeared to make E. coli PI-7 more susceptible to solar disinfection and bacteriophage infection. Our findings suggest that bacteriophages show good potential to be used as a biocontrol tool to complement solar irradiation in mitigating the persistence of antibiotic-resistant bacteria in reuse waters.
Original language | English (US) |
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Pages (from-to) | 14331-14341 |
Number of pages | 11 |
Journal | Environmental Science & Technology |
Volume | 52 |
Issue number | 24 |
DOIs | |
State | Published - Nov 20 2018 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): BAS/1/1033-01-01, URF/1/2982-01-01
Acknowledgements: This study is supported by KAUST baseline funding BAS/1/1033-01-01 and Competitive Research Grant No. URF/1/2982-01-01 awarded to P.-Y.H.