| Title | Zooplankton as a Transitional Host for Escherichia coli in Freshwater |
| Abstract | This study shows that Escherichia coli can be temporarily enriched in zooplankton under natural conditions and that these bacteria can belong to different phylogroups and sequence types (STs), including environmental, clinical, and animal isolates. We isolated 10 E. coli strains and sequenced the genomes of two of them. Phylogenetically, the two isolates were closer to strains isolated from poultry meat than to freshwater E. coli, albeit their genomes were smaller than those of the poultry isolates. After isolation and fluorescent protein tagging of strains ED1 and ED157, we show that Daphnia sp. can take up these strains and release them alive again, thus becoming a temporary host for E. coli. In a chemostat experiment, we show that this association does not prolong bacterial long-term survival, but at low abundances it also does not significantly reduce bacterial numbers. We demonstrate that E. coli does not belong to the core microbiota of Daphnia, suffers from competition by the natural Daphnia microbiota, but can profit from its carapax to survive in water. All in all, this study suggests that the association of E. coli with Daphnia is only temporary, but the cells are viable therein, and this might allow encounters with other bacteria for genetic exchange and potential genomic adaptation to the freshwater environment. |
| Source | Applied and environmental microbiology (Print) 88 (9) |
| Keywords | Escherichia coliDaphniafecal indicator bacteriafreshwaterlakezooplankton |
| Journal | Applied and environmental microbiology (Print) |
| Editor | American Society for Microbiology., [Washington], Stati Uniti d'America |
| Year | 2022 |
| Type | Articolo in rivista |
| DOI | 10.1128/aem.02522-21 |
| Authors | di Cesare, Andrea; Riva, Francesco; Colinas, Noemi; Borgomaneiro, Giulia; Borin, Sara; Cabello-Yeves, Pedro J.; Canale, Claudia; Cedraro, Nicholas; Citterio, Barbara; Crotti, Elena; Mangiaterra, Gianmarco; Mapelli, Francesca; Mondino, Vincenzo; Vignaroli, Carla; Quaranta, Walter; Corno, Gianluca; Fontaneto, Diego; Eckert, Ester M. |
| Text | 467402 2022 10.1128/aem.02522 21 ISI Web of Science WOS 000784211000005 Escherichia coli Daphnia fecal indicator bacteria freshwater lake zooplankton Zooplankton as a Transitional Host for Escherichia coli in Freshwater di Cesare, Andrea; Riva, Francesco; Colinas, Noemi; Borgomaneiro, Giulia; Borin, Sara; Cabello Yeves, Pedro J.; Canale, Claudia; Cedraro, Nicholas; Citterio, Barbara; Crotti, Elena; Mangiaterra, Gianmarco; Mapelli, Francesca; Mondino, Vincenzo; Vignaroli, Carla; Quaranta, Walter; Corno, Gianluca; Fontaneto, Diego; Eckert, Ester M. Natl Res Council Italy; Univ Milan; Univ Valencia; Univ Miguel Hernandez Elche; ASL VCO Castelli Hosp; Polytech Univ Marche; Univ Urbino Carlo Bo; ASL VCO Castelli Hosp This study shows that Escherichia coli can be temporarily enriched in zooplankton under natural conditions and that these bacteria can belong to different phylogroups and sequence types STs , including environmental, clinical, and animal isolates. We isolated 10 E. coli strains and sequenced the genomes of two of them. Phylogenetically, the two isolates were closer to strains isolated from poultry meat than to freshwater E. coli, albeit their genomes were smaller than those of the poultry isolates. After isolation and fluorescent protein tagging of strains ED1 and ED157, we show that Daphnia sp. can take up these strains and release them alive again, thus becoming a temporary host for E. coli. In a chemostat experiment, we show that this association does not prolong bacterial long term survival, but at low abundances it also does not significantly reduce bacterial numbers. We demonstrate that E. coli does not belong to the core microbiota of Daphnia, suffers from competition by the natural Daphnia microbiota, but can profit from its carapax to survive in water. All in all, this study suggests that the association of E. coli with Daphnia is only temporary, but the cells are viable therein, and this might allow encounters with other bacteria for genetic exchange and potential genomic adaptation to the freshwater environment. The contamination of freshwater with feces derived bacteria is a major concern regarding drinking water acquisition and recreational activities. Ecological interactions promoting their persistence are still very scarcely studied. This study, which analyses the survival of E. coli in the presence of zooplankton, is thus of ecological and water safety relevance. 88 Published version https //journals.asm.org/doi/10.1128/aem.02522 21 aem aem.02522 21.pdf Articolo in rivista American Society for Microbiology. 0099 2240 Applied and environmental microbiology Print Applied and environmental microbiology Print Appl. environ. microbiol. Print Applied and environmental microbiology. Print BORGOMANEIRO GIULIA gianluca.corno CORNO GIANLUCA diego.fontaneto FONTANETO DIEGO andrea.dicesare DI CESARE ANDREA estermaria.eckert ECKERT ESTER MARIA |
