Exploring bacterial pathogen community dynamics in freshwater beach sediments: A tale of two lakes
Corresponding Author
Danielle VanMensel
Great Lakes Institute for Environmental Research, University of Windsor, Ontario, Canada
For correspondence. E-mail [email protected]; Tel. (+519) 253 3000 x4739Search for more papers by this authorSubba Rao Chaganti
Great Lakes Institute for Environmental Research, University of Windsor, Ontario, Canada
Cooperative Institute for Great Lakes Research, University of Michigan, Ann Arbor, MI, USA
Search for more papers by this authorIan G. Droppo
Environment and Climate Change Canada, Burlington, Ontario, Canada
Search for more papers by this authorChristopher G. Weisener
Great Lakes Institute for Environmental Research, University of Windsor, Ontario, Canada
Search for more papers by this authorCorresponding Author
Danielle VanMensel
Great Lakes Institute for Environmental Research, University of Windsor, Ontario, Canada
For correspondence. E-mail [email protected]; Tel. (+519) 253 3000 x4739Search for more papers by this authorSubba Rao Chaganti
Great Lakes Institute for Environmental Research, University of Windsor, Ontario, Canada
Cooperative Institute for Great Lakes Research, University of Michigan, Ann Arbor, MI, USA
Search for more papers by this authorIan G. Droppo
Environment and Climate Change Canada, Burlington, Ontario, Canada
Search for more papers by this authorChristopher G. Weisener
Great Lakes Institute for Environmental Research, University of Windsor, Ontario, Canada
Search for more papers by this authorSummary
Pathogenic bacteria associated with freshwater ecosystems can pose significant health risks particularly where recreational water use is popular. Common water quality assessments involve quantifying indicator Escherichia coli within the water column but neglect to consider physical and geochemical factors and contributions from the sediment. In this study, we used high-throughput sequencing to investigate sediment microbial communities at four freshwater public beaches in southern Ontario, Canada and analysed community structure, function, and gene expression with relation to geographical characteristics. Our results indicate that beach sediments at the sediment–water interface could serve as potential sources of bacterial contamination under low-energy environments with tightly packed small sediment particles compared with high-energy environments. Further, the absence of pathogens but expression of pathogenic transcripts suggests occurrence of alternate gene acquisition. Pathogenicity at these locations included expression of Salmonella virulence factors, genes involved in pertussis, and antimicrobial resistance. Finally, we introduce a proposed universal bacterial pathogen model to consider the combined and synergistic processes used by these microbes. To our knowledge, this is the first study of its kind to investigate chemolithotrophic activity related to pathogens within bed sediment at freshwater beaches. This work helps advance current understanding of health risks in these environments.
Supporting Information
Filename | Description |
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emi14860-sup-0001-Figures.docxWord 2007 document , 291.5 KB | Figure S1 Line graph depicting the percentage of incidences that reported CFU values of indicator E. coli in the water at WEC public beaches exceeded acceptable levels over the past 7 years. Thick solid lines indicate locations of interest to this manuscript (Belle River (BR), Holiday (HD), Kingsville (KV), Sandpoint (SP)), and thin dashed lines represent the other beaches monitored. Data provided by WECHU. Note: up until 2017, acceptable E. coli levels were less than 100 CFUs/100 mL; 2018 it changed to 200 CFUs/100 mL. |
emi14860-sup-0001-Tables.xlsxExcel 2007 spreadsheet , 44 KB | Table S1 Summary of sequencing statistics for metabarcoding data obtained from the Ion Torrent PGM Table S2 Summary of sequencing statistics for all samples obtained from the Illumina HiSeq 4000 run |
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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