Microplastics increase impact of treated wastewater on freshwater microbial community,

Environmental Pollution,
Volume 234,
2018,
Pages 495-502,
ISSN 0269-7491,

Abstract:

Plastic pollution is a major global concern with several million microplastic particles entering every day freshwater ecosystems via wastewater discharge. Microplastic particles stimulate biofilm formation (plastisphere) throughout the water column and have the potential to affect microbial community structure if they accumulate in pelagic waters, especially enhancing the proliferation of biohazardous bacteria.

To test this scenario, we simulated the inflow of treated wastewater into a temperate lake using a continuous culture system with a gradient of concentration of microplastic particles. We followed the effect of microplastics on the microbial community structure and on the occurrence of integrase 1 (int1), a marker associated with mobile
genetic elements known as a proxy for anthropogenic effects on the spread of antimicrobial resistance genes. The abundance of int1 increased in the plastisphere with increasing microplastic particle concentration, but not in the water surrounding the microplastic particles.
Likewise, the microbial community on microplastic was more similar to the original wastewater community with increasing microplastic concentrations.
Our results show that microplastic particles indeed promote persistence of typical indicators of microbial
anthropogenic pollution in natural waters, and substantiate that their removal from treated wastewater should be prioritised.

https://drive.google.com/open?id=1HtDKuEcm5DuPU_jpXE0Ag72qhHa74Lmd
https://doi.org/10.1016/j.envpol.2017.11.070.
(http://www.sciencedirect.com/science/article/pii/S0269749117339775)

The post Microplastics increase impact of treated wastewater on freshwater microbial community appeared first on One Earth - One Ocean e. V..

Volume 237, 2018, Pages 253-261, ISSN 0269-7491,

Abstract:

Pollution by microplastics in aquatic ecosystems is accumulating at an unprecedented scale,
emerging as a new surface for biofilm formation and gene exchange. In this study, we determined the
permissiveness of aquatic bacteria towards a model antibiotic resistance plasmid, comparing communities
that form biofilms on microplastics vs. those that are free-living.
We used an exogenous and red-fluorescent E. coli donor strain to introduce the green-fluorescent
broad-host-range plasmid pKJK5 which encodes for trimethoprim resistance. We demonstrate an increased frequency of plasmid transfer in bacteria associated with microplastics compared to bacteria that are
free-living or in natural aggregates. Moreover, comparison of communities grown on polycarbonate filters
showed that increased gene exchange occurs in a broad range of phylogenetically-diverse bacteria. Our results indicate horizontal gene transfer in this habitat could distinctly affect the ecology of aquatic microbial
communities on a global scale.
The spread of antibiotic resistance through microplastics could also have profound consequences for the evolution
of aquatic bacteria and poses a neglected hazard for human health.

https://drive.google.com/open?id=1HbX9nqqON579PbGKYNYoE3MFciJLtVix

https://doi.org/10.1016/j.envpol.2018.02.058.(http://www.sciencedirect.com/science/article/pii/S0269749117349990)

The post Microplastic pollution increases gene exchange in aquatic ecosystems, Environmental Pollution appeared first on One Earth - One Ocean e. V..

Microplastic pollution increases gene exchange in aquatic ecosystems,
Environmental Pollution, Volume 237, 2018, Pages 253-261, ISSN 0269-7491,

Abstract:

Pollution by microplastics in aquatic ecosystems is accumulating at an unprecedented scale, emerging as a new surface for biofilm formation and gene exchange. In this study, we determined the permissiveness of aquatic bacteria towards a model antibiotic resistance plasmid, comparing communities that form biofilms on microplastics vs.
those that are free-living. We used an exogenous and red-fluorescent E. coli donor strain to introduce the green-fluorescent broad-host-range plasmid pKJK5 which encodes for trimethoprim resistance.
We demonstrate an increased frequency of plasmid transfer in bacteria associated with
microplastics compared to bacteria that are free-living or in natural aggregates. Moreover, comparison of communities grown on polycarbonate filters showed that increased gene exchange occurs in a broad range of phylogenetically-diverse bacteria. Our results indicate horizontal gene transfer in this habitat could distinctly affect the ecology of aquatic microbial communities on a global scale. The spread of antibiotic
resistance through microplastics could also have profound consequences for the evolution of aquatic bacteria and poses a neglected hazard for human health.

https://drive.google.com/open?id=1HbX9nqqON579PbGKYNYoE3MFciJLtVix
https://doi.org/10.1016/j.envpol.2018.02.058.(http://www.sciencedirect.com/science/article/pii/S0269749117349990)

The post Microplastic pollution increases gene exchange in aquatic ecosystems appeared first on One Earth - One Ocean e. V..