Limits...
The contribution of Escherichia coli from human and animal sources to the integron gene pool in coastal waters.

Moura A, Araújo S, Alves MS, Henriques I, Pereira A, Correia AC - Front Microbiol (2014)

Bottom Line: Common arrays were found among strains from different sources.In 20% (15/76) of strains, integrons were successfully mobilized through conjugation to E. coli CV601.Results obtained support the existence of a diverse integron pool in the E. coli strains from this coastal environment, associated with different resistance traits and plasmid incompatibility groups, mainly shaped by animal fecal pollution inputs.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and CESAM, University of Aveiro Aveiro, Portugal.

ABSTRACT
To understand the contribution of animal- and human-derived fecal pollution sources in shaping integron prevalence and diversity in beach waters, 414 Escherichia coli strains were collected from beach waters (BW, n = 166), seagull feces (SF, n = 179), and wastewaters (WW, n = 69), on the World Biosphere Reserve of the Berlenga Island, Portugal. Statistical differences were found between the prevalence of integrons in BW (21%) and WW (10%), but not between BW and SF (19%). The majority of integrase-positive (intI (+))-strains affiliated to commensal phylogroups B1 (37%), A0 (24%), and A1 (20%). Eighteen different gene cassette arrays were detected, most of them coding for resistances to aminoglycosides, trimethoprim, chloramphenicol, and quaternary ammonia compounds. Common arrays were found among strains from different sources. Multi-resistance to three or more different classes of antibiotics was observed in 89, 82, and 57% of intI (+)-strains from BW, SF and WW, respectively. Plasmids were detected in 79% of strains (60/76) revealing a high diversity of replicons in all sources, mostly belonging to IncF (Frep, FIA, and FIB subgroups), IncI1, IncN, IncY, and IncK incompatibility groups. In 20% (15/76) of strains, integrons were successfully mobilized through conjugation to E. coli CV601. Results obtained support the existence of a diverse integron pool in the E. coli strains from this coastal environment, associated with different resistance traits and plasmid incompatibility groups, mainly shaped by animal fecal pollution inputs. These findings underscore the role of wild life in dissemination of integrons and antibiotic resistance traits in natural environments.

No MeSH data available.


Related in: MedlinePlus

Prevalence of intI+-E. coli detected in the Berlenga Island among different sources (A) and phylogroups (B). Statistical significance: *P < 0.05; **P < 0.01; n.s., not significant.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4129628&req=5

Figure 1: Prevalence of intI+-E. coli detected in the Berlenga Island among different sources (A) and phylogroups (B). Statistical significance: *P < 0.05; **P < 0.01; n.s., not significant.

Mentions: Overall, nearly 20% (76/414) of strains harbored intI genes (Figure 1A). Prevalence of class 1 and class 2 integron integrases was 18 and 2% in BW, 19 and 0.5% in SF and 10 and 0% in WW, respectively. Previous studies targeting antibiotic resistant bacteria in similar environments (Dolejska et al., 2009) have reported comparable prevalence of class 1 integrons in E. coli from surface waters (21%) and black-headed gulls (Larus ridibundus) nesting nearby (15%), although with higher prevalence of intI2 in gulls (11%). Prevalence found at the untreated effluent of Berlengas was also similar to those found in raw human- and animal-derived wastewaters (Moura et al., 2007, 2012b). In this study, differences between prevalence of intI genes in BW and WW were statistically different (χ21 = 3.98; P < 0.05), but not between BW and SF (χ21 = 0.261; P > 0.05). These results confirm the significant contribution of seagull microbiota in shaping the prevalence of integrons in this ecosystem.


The contribution of Escherichia coli from human and animal sources to the integron gene pool in coastal waters.

Moura A, Araújo S, Alves MS, Henriques I, Pereira A, Correia AC - Front Microbiol (2014)

Prevalence of intI+-E. coli detected in the Berlenga Island among different sources (A) and phylogroups (B). Statistical significance: *P < 0.05; **P < 0.01; n.s., not significant.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4129628&req=5

Figure 1: Prevalence of intI+-E. coli detected in the Berlenga Island among different sources (A) and phylogroups (B). Statistical significance: *P < 0.05; **P < 0.01; n.s., not significant.
Mentions: Overall, nearly 20% (76/414) of strains harbored intI genes (Figure 1A). Prevalence of class 1 and class 2 integron integrases was 18 and 2% in BW, 19 and 0.5% in SF and 10 and 0% in WW, respectively. Previous studies targeting antibiotic resistant bacteria in similar environments (Dolejska et al., 2009) have reported comparable prevalence of class 1 integrons in E. coli from surface waters (21%) and black-headed gulls (Larus ridibundus) nesting nearby (15%), although with higher prevalence of intI2 in gulls (11%). Prevalence found at the untreated effluent of Berlengas was also similar to those found in raw human- and animal-derived wastewaters (Moura et al., 2007, 2012b). In this study, differences between prevalence of intI genes in BW and WW were statistically different (χ21 = 3.98; P < 0.05), but not between BW and SF (χ21 = 0.261; P > 0.05). These results confirm the significant contribution of seagull microbiota in shaping the prevalence of integrons in this ecosystem.

Bottom Line: Common arrays were found among strains from different sources.In 20% (15/76) of strains, integrons were successfully mobilized through conjugation to E. coli CV601.Results obtained support the existence of a diverse integron pool in the E. coli strains from this coastal environment, associated with different resistance traits and plasmid incompatibility groups, mainly shaped by animal fecal pollution inputs.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and CESAM, University of Aveiro Aveiro, Portugal.

ABSTRACT
To understand the contribution of animal- and human-derived fecal pollution sources in shaping integron prevalence and diversity in beach waters, 414 Escherichia coli strains were collected from beach waters (BW, n = 166), seagull feces (SF, n = 179), and wastewaters (WW, n = 69), on the World Biosphere Reserve of the Berlenga Island, Portugal. Statistical differences were found between the prevalence of integrons in BW (21%) and WW (10%), but not between BW and SF (19%). The majority of integrase-positive (intI (+))-strains affiliated to commensal phylogroups B1 (37%), A0 (24%), and A1 (20%). Eighteen different gene cassette arrays were detected, most of them coding for resistances to aminoglycosides, trimethoprim, chloramphenicol, and quaternary ammonia compounds. Common arrays were found among strains from different sources. Multi-resistance to three or more different classes of antibiotics was observed in 89, 82, and 57% of intI (+)-strains from BW, SF and WW, respectively. Plasmids were detected in 79% of strains (60/76) revealing a high diversity of replicons in all sources, mostly belonging to IncF (Frep, FIA, and FIB subgroups), IncI1, IncN, IncY, and IncK incompatibility groups. In 20% (15/76) of strains, integrons were successfully mobilized through conjugation to E. coli CV601. Results obtained support the existence of a diverse integron pool in the E. coli strains from this coastal environment, associated with different resistance traits and plasmid incompatibility groups, mainly shaped by animal fecal pollution inputs. These findings underscore the role of wild life in dissemination of integrons and antibiotic resistance traits in natural environments.

No MeSH data available.


Related in: MedlinePlus