We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Spatial Environmental Heterogeneity Determines Young Biofilm Assemblages on Microplastics in Baltic Sea Mesocosms
Summary
Mesocosm experiments in the Baltic Sea found that spatial environmental heterogeneity - differences in light, nutrients, and water chemistry across microhabitats - was a key driver of the microbial biofilm communities that formed on microplastic surfaces during early colonization. This suggests that local environmental conditions shape the "plastisphere" microbiome as much as the plastic substrate itself.
Microplastics in aquatic environments provide novel habitats for surface-colonizing microorganisms. Given the continuing debate on whether substrate-specific properties or environmental factors prevail in shaping biofilm assemblages on microplastics, we examined the influence of substrate vs. spatial factors in the development of bacterial assemblages on polyethylene (PE), polystyrene (PS), wood, and seston and in the free-living fraction. Further, the selective colonization of microplastics by potential pathogens was investigated because among the bacterial species found in microplastic-associated biofilms are potentially pathogenic Vibrio spp. Due to their persistence and great dispersal potential, microplastics could act as vectors for these potential pathogens and for biofilm assemblages in general. Incubation experiments with these substrates were conducted for 7 days during a summer cruise along the eastern Baltic Sea coastline in waters covering a salinity gradient of 4.5-9 PSU. Bacterial assemblages were analyzed using 16S rRNA-gene amplicon sequencing, distance-based redundancy analyses, and the linear discriminant analysis effect size method to identify taxa that were significantly more abundant on the plastics. The results showed that the sample type was the most important factor structuring bacterial assemblages overall. Surface properties were less significant in differentiating attached biofilms on PE, PS, and wood; instead, environmental factors, mainly salinity, prevailed. A potential role for inorganic-nutrient limitations in surface-specific attachment was identified as well. Alphaproteobacteria (Sphingomonadaceae, Devosiaceae, and Rhodobacteraceae) and Gammaproteobacteria (Alteromonadaceae and Pseudomonas) were distinctive for the PE- and PS-associated biofilms. Vibrio was more abundant on the PE and PS biofilms than on seston, but its abundances were highest on wood and positively correlated with salinity. These results corroborate earlier findings that microplastics constitute a habitat for biofilm-forming microorganisms distinct from seston, but less from wood. In contrast to earlier reports of low Vibrio numbers on microplastics, these results also suggest that vibrios are early colonizers of surfaces in general. Spatial as well as temporal dynamics should therefore be considered when assessing the potential of microplastics to serve as vectors for bacterial assemblages and putative pathogens, as these parameters are major drivers of biofilm diversity.
Sign in to start a discussion.
More Papers Like This
Evidence for selective bacterial community structuring on microplastics
Plastic substrates incubated in Baltic Sea water developed distinct bacterial communities that differed significantly from those on glass surfaces and from the surrounding water, with some plastic-colonizing taxa selected for regardless of polymer type. The study provides experimental evidence that plastic surfaces act as selective filters for microbial community assembly, contributing to the concept of a unique plastisphere.
Spatial and seasonal variation in diversity and structure of microbial biofilms on marine plastics in Northern European waters
Researchers investigated how microbial biofilm communities on marine plastics vary by season, location, and plastic type in Northern European waters. The study found distinct spatial and seasonal patterns in plastisphere microbial communities on polyethylene terephthalate surfaces, providing insights into how plastic debris develops unique biological communities in marine environments.
The structure and assembly mechanisms of plastisphere microbial community in natural marine environment
Researchers investigated how microbial communities colonize different types of microplastic surfaces in natural marine environments over an eight-week period. They found that the composition of these plastic-associated microbial communities, known as the plastisphere, was shaped more by environmental conditions and time than by the specific type of plastic. The study provides new understanding of the ecological processes governing how microorganisms assemble on ocean plastic debris.
Structural Diversity in Early-Stage Biofilm Formation on Microplastics Depends on Environmental Medium and Polymer Properties
This study examined the early stages of bacterial biofilm formation on different types of plastic surfaces in different environmental media, finding that both the growth medium and the polymer type influenced which microbial communities colonized the plastic. These plastic-associated biofilms (the plastisphere) can make microplastics more appealing to filter-feeding organisms that mistake them for food.
Time-series incubations in a coastal environment illuminates the importance of early colonizers and the complexity of bacterial biofilm dynamics on marine plastics
Researchers used time-series incubations in a coastal marine environment to track plastisphere biofilm formation on microplastics, finding that early bacterial colonizers play a disproportionate role in shaping community dynamics and that biofilm composition is highly complex, varying with polymer type, incubation time, and surrounding environment.