ABSTRACT: A new genus Paramaribius gen. nov. with a new moderately halophilic species isolated from the surface of a polyethylene microplastic particle after incubation in a marine aquaria system
Project description:Salicibibacter kimchii gen. nov., sp. nov., a moderately halophilic and alkalitolerant bacterium in the family Bacillaceae, isolated from kimchi
Project description:The freshwater mussel Dreissena bugensis was exposed for nine days to different microplastic particles, in detail, to three petroleum-based polymers (polyamide (PA), polyethylene terephthalate (PET), polystyrene (PS)), to one bio-based polymer (polylactic acid (PLA)) and to ground mussel shells (MS), serving as a natural particle control (size range: 20-75 µm;1000 p ml-1). Behavior endpoints were analyzed with hall sensor based real-time valvometry. Additionally, biochemical alterations of ROS detoxifying enzymes were analyzed, and a proteomic profiling on digestive gland tissue was performed.
Project description:The contamination of marine ecosystems with microplastics, such as the polymer polyethylene, a commonly used component of single-use packaging, is of global concern. Although it has been suggested that biodegradable polymers, such as polylactic acid, may be used to replace some polyethylene packaging, little is known about their effects on marine organisms. Blue mussels, Mytilus edulis, have become a “model organism” for investigating the effects of microplastics in marine ecosystems. We show here that repeated exposure, over a period of 52 days in an outdoor mesocosm setting, of M. edulis to polyethylene microplastics reduced the number of byssal threads produced and the attachment strength (tenacity) by ~50%. Exposure to either type of microplastic altered the haemolymph proteome and, although a conserved response to microplastic exposure was observed, overall polyethylene resulted in more changes to protein abundances than polylactic acid. Many of the proteins affected are involved in vital biological processes, such as immune- and stress- regulation, metabolism and cellular and structural development. Our study highlights the utility of mass spectrometry-based proteomics to assess the health of key marine organisms and identifies the potential mechanisms by which microplastics, both conventional and biodegradable, could affect their ability to form and maintain reefs.