Comparative accessory gene fingerprinting of surface water <i>Escherichia coli</i>
 reveals genetically diverse naturalized population

Tymensen, Lisa; Pyrdok, F.; Coles, D.; Koning, Wendell; McAllister, Tim A.; Jokinen, Cassandra C.; Dowd, Scot E.; Neumann, Norman F.

doi:10.1111/jam.12814

Cited by 35 publications

(35 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Naturalized strains of E. coli have been identified in various water sources (6–8), but to date, evidence for the presence of naturalized strains of E. coli in a wastewater environment has not been reported.…”

Section: Discussionmentioning

confidence: 99%

“…However, naturalized strains of E. coli have been described for sand, sediment, and water (5–9), and as such, it may be presumptuous to assume that all E. coli strains observed in wastewater are of fecal origin, creating some authenticity to the emerging yet controversial concept that naturalized strains of E.…”

Section: Discussionmentioning

confidence: 99%

“…Naturalized E. coli strains have also been described for sand, sediments, and water from temperate climates (5–9). The presence of E.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Evidence of Naturalized Stress-Tolerant Strains of Escherichia coli in Municipal Wastewater Treatment Plants

Zhi

Banting

et al. 2016

Appl Environ Microbiol

View full text Add to dashboard Cite

Escherichia coli has been proposed to have two habitats—the intestines of mammals/birds and the nonhost environment. Our goal was to assess whether certain strains of E. coli have evolved toward adaptation and survival in wastewater. Raw sewage samples from different treatment plants were subjected to chlorine stress, and ∼59% of the surviving E. coli strains were found to contain a genetic insertion element (IS30) located within the uspC-flhDC intergenic region. The positional location of the IS30 element was not observed across a library of 845 E. coli isolates collected from various animal hosts or within GenBank or whole-genome reference databases for human and animal E. coli isolates (n = 1,177). Phylogenetics clustered the IS30 element-containing wastewater E. coli isolates into a distinct clade, and biomarker analysis revealed that these wastewater isolates contained a single nucleotide polymorphism (SNP) biomarker pattern that was specific for wastewater. These isolates belonged to phylogroup A, possessed generalized stress response (RpoS) activity, and carried the locus of heat resistance, features likely relevant to nonhost environmental survival. Isolates were screened for 28 virulence genes but carried only the fimH marker. Our data suggest that wastewater contains a naturalized resident population of E. coli. We developed an endpoint PCR targeting the IS30 element within the uspC-flhDC intergenic region, and all raw sewage samples (n = 21) were positive for this marker. Conversely, the prevalence of this marker in E. coli-positive surface and groundwater samples was low (≤5%). This simple PCR assay may represent a convenient microbial source-tracking tool for identification of water samples affected by municipal wastewater.IMPORTANCE The results of this study demonstrate that some strains of E. coli appear to have evolved to become naturalized populations in the wastewater environment and possess a number of stress-related genetic elements likely important for survival in this nonhost environment. The presence of non-host-adapted strains in wastewater challenges our understanding of using E. coli as a microbial indicator of wastewater treatment performance, suggesting that the E. coli strains present in human and animal feces may be very different from those found in treated wastewater.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Evidence of Naturalized Stress-Tolerant Strains of Escherichia coli in Municipal Wastewater Treatment Plants

Zhi

Banting

et al. 2016

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…; Tymensen et al . ). These populations have been reported in sand, soil and sediments as well as in association with macrophytic algae and periphyton (Ishii and Sadowsky ; Sadowsky and Whitman ).…”

Section: Survival and Growth Of Escherichia Coli In Natural Environmentmentioning

confidence: 97%

EnvironmentalEscherichia coli: ecology and public health implications-a review

et al. 2017

View full text Add to dashboard Cite

Summary Escherichia coli is classified as a rod‐shaped, Gram‐negative bacterium in the family Enterobacteriaceae. The bacterium mainly inhabits the lower intestinal tract of warm‐blooded animals, including humans, and is often discharged into the environment through faeces or wastewater effluent. The presence of E. coli in environmental waters has long been considered as an indicator of recent faecal pollution. However, numerous recent studies have reported that some specific strains of E. coli can survive for long periods of time, and potentially reproduce, in extraintestinal environments. This indicates that E. coli can be integrated into indigenous microbial communities in the environment. This naturalization phenomenon calls into question the reliability of E. coli as a faecal indicator bacterium (FIB). Recently, many studies reported that E. coli populations in the environment are affected by ambient environmental conditions affecting their long‐term survival. Large‐scale studies of population genetics revealed the diversity and complexity of E. coli strains in various environments, which are affected by multiple environmental factors. This review examines the current knowledge on the ecology of E. coli strains in various environments with regard to its role as a FIB and as a naturalized member of indigenous microbial communities. Special emphasis is given on the growth of pathogenic E. coli in the environment, and the population genetics of environmental members of the genus Escherichia. The impact of environmental E. coli on water quality and public health is also discussed.

show abstract

“…It has been generally assumed that this bacterium is restricted to the gastrointestinal system of warm-blooded animals, but several studies have found that E. coli can survive and replicate outside the gastrointestinal tract of animals in a non-host environment (water/sand/sediment) (Anderson et al, 2005;Byappanahalli et al, 2012;Chandrasekaran et al, 2015;Kon et al, 2007;Power et al, 2005;Solo-Gabriele et al, 2000;Tymensen et al, 2015;Winfield and Groisman, 2003). Survival and colonisation in both the animal host and non-host habitats are mediated by adaptations to nutrient availability, temperature, pH, osmolarity and the presence of competitive microflora.…”

Section: Introductionmentioning

confidence: 99%

Stress resistance in naturalised waste water E. coli strains

Zhi

BantingGraham

RueckerNorma³

et al. 2017

Journal of Environmental Engineering and Science

View full text Add to dashboard Cite

The authors recently demonstrated that naturalised strains of Escherichia coli exist in municipal waste water, characterised by (a) biomarker patterns in intergenic regions distinct from human and animal E. coli strains and (b) an insertion element (IS30) located in the uspC-flhDC intergenic region of the genome. Remarkably, these strains are naturally adapted to survival and growth in waste water and differentially survive the treatment process. The authors sought to explore the adaptive mechanisms used by these strains for survival. A serial stress experiment (nutrient deprivation and osmotic stress followed by chlorine treatment) was performed and survival was measured using culture. Waste water strains were shown to be approximately 100 times more resistant to chlorine treatment than a wild-type human faecal strain. Naturalised waste water strains were also more robust at producing biofilmsan adaptive strategy for surviving environmental stressors. Since biofilm formation has been linked to increased motility, the authors examined the expression of the flagellar regulator gene, flhDC, under serial stress conditions. Chlorine was a potent inducer of flhDC expression in waste water strains. The results demonstrate that waste water strains possess adaptive genotypic/phenotypic properties related to their survival in waste water and challenge the understanding of treatment reduction based on E. coli as an indicator of treatment performance.

show abstract

Comparative accessory gene fingerprinting of surface water Escherichia coli reveals genetically diverse naturalized population

Abstract: Accessory gene fingerprinting may have important practical implications for improving the specificity of methods that are widely used for quantifying and identifying the sources of faecal contamination in surface water.

Cited by 35 publications

References 42 publications

Evidence of Naturalized Stress-Tolerant Strains of Escherichia coli in Municipal Wastewater Treatment Plants

Evidence of Naturalized Stress-Tolerant Strains of Escherichia coli in Municipal Wastewater Treatment Plants

EnvironmentalEscherichia coli: ecology and public health implications-a review

Stress resistance in naturalised waste water E. coli strains

Contact Info

Product

Resources

About