Polystyrene influences bacterial assemblages in Arenicola marina-populated aquatic environments in vitro. (December 2016) - Kesy, Katharina
Abstract: Plastic is ubiquitous in global oceans and constitutes a newly available habitat for surface-associated bacterial assemblages. Microplastics (plastic particles <5 mm) are especially susceptible to ingestion by marine organisms, as the size of these particles makes them available also to lower trophic levels. Because many marine invertebrates harbour potential pathogens in their guts, we investigated whether bacterial assemblages on polystyrene are selectively modified during their passage through the gut of the lugworm Arenicola marina and are subsequently able to develop pathogenic biofilms. We also examined whether polystyrene acts as a vector for gut biofilm assemblages after subsequent incubation of the egested particles in seawater. Our results showed that after passage through the digestive tract of A. marina, the bacterial assemblages on polystyrene particles and reference glass beads became more similar, harbouring common sediment bacteria. By contrast, only in the presence of polystyrene the potential symbiont Amphritea atlantica was enriched in the investigated biofilms, faeces, and water. Thus, especially in areas of high polystyrene contamination, this polymer may impact the bacterial composition of different habitats, with as yet unknown consequences for the respective ecosystems. Graphical abstract: Highlights: Polystyrene-associated biofilms were analysed before and after gut passage of Arenicola marina in a laboratory experiment. The bacterial assemblages on polystyrene, faeces and glass became more similar after gut passage. Independent of the presence of A. marina, polystyrene enriched for the bacterium Amphritea sp. in biofilms and water samples. Abstract : This research highlights the impact of polystyrene contamination on the establishment of bacterial assemblages and the enrichment of the potential endosymbiont Amphritea atlantica in an Arenicola marina -populated aquatic environment under experimental conditions.