Microbial communities colonizing plastic in the Nile River

Rivers are a major transport vector for plastic litter but rivers also retain large amounts of plastic for long time periods before releasing their plastic load to the ocean. Plastic litter in aquatic systems is typically covered by biofilms. However, it is not clear which microbial communities colonise plastics in river ecosystems and whether the biofilm composition is stable as the plastic fragments are transported with the current. Here, we investigated microbial communities on floating plastics and in river water at three locations along the Nile River (Egypt). At all locations, the collected plastics were primarily composed of polystyrene and polyethylene as shown by Raman spectroscopy. Significant differences were found in the composition of microbial communities in water samples compared to the plastic-associated biofilms, indicating that specific microbial communities colonize plastics. Irrespective of location, the prokaryotic community was dominated by the orders of Burkholderiales, Cytophagales and Chitinophagales, as revealed by 16S rRNA gene sequencing. Furthermore, we detected sequences assigned to hydrocarbon-degrading bacteria including the genus Ideonella which made up ¿2 Also see: micro2024.sciencesconf.org In MICRO 2024: Plastic Pollution from MACRO to nano