Microbial amplicon sequencing of biofilms on microplastics of a eutrophic reservoir
Ontology highlight
ABSTRACT: Microbial biofilms on various microplastics of a eutrophic reservoir (Bautzen, Germany). Amplicon sequencing of the V4-V5 region of the microbial 16S and 18S rRNA gene.
Project description:Microplastics represent a growing environmental concern for the oceans due to their potential capability to adsorb different classes of pollutants, thus representing a still unexplored source of exposure for aquatic organisms. In this study polystyrene (PS) microplastics were characterized for their capability to adsorb pyrene (PYR) as model compound for polycyclic aromatic hydrocarbons, and transfer this chemical to filter feeding mussels Mytilus galloprovincialis. Gene expression analyses of Mytilus galloprovincialis exposed to polystyrene (PS) microplastics and to polystyrene contaminated with pyrene (PS-PYR) have been performed trough a DNA microarray platform.
Project description:Polyethylene microplastics are pervasive environmental pollutants that pose potential risks to aquatic organisms. This study investigates the effects of polyethylene microplastics on zebrafish (Danio rerio) embryo development, with a focus on whether the chorion, a protective barrier surrounding the embryo, is effective in blocking polyethylene penetration. Contrary to previous findings that suggested the chorion could prevent larger microplastics (>0.7 µm) from entering, our study demonstrates that polyethylene particles sized 1-4 µm can still negatively impact embryo development without dechorionation. Embryos were exposed to polyethylene at concentrations of 0.01, 0.1, and 1 mg/L, followed by RNA sequencing to assess gene expression changes. Despite no significant differences in survival, hatching, or body length between control and treated groups, a significant reduction in heart rate was observed at higher concentrations, indicating potential sub-lethal cardiotoxicity. Further, qRT-PCR validation confirmed significant downregulation of key heart development-related genes, particularly fbln1 and fn1b, in polyethylene-exposed embryos. Additionally, polyethylene exposure also impacted Daphnia magna, reducing heart rate and delaying growth. These findings highlight the ability of polyethylene microplastics to penetrate natural barriers such as the chorion and induce physiological and developmental changes. Our results emphasize the need for further research into the long-term effects of microplastic exposure on aquatic ecosystems.
Project description:Microplastics are a relatively newly discovered environmental hazard that can contribute to the disruption of many physiological processes in the organism. There is evidence that they affect the physiology of the pancreas, but research is still very limited. Therefore, the aim of the study was to determine the effects of PET microplastics on the global proteomic profile of the porcine pancreas using LC-MS/MS analysis. The pigs were treated with a low (0.1 g/day) or a high dose (1 g/day) of PET microplastics for 4 weeks. The analysis revealed that PET microplastics affected protein expression in a dose-dependent manner - the low dose affected the abundance of 7 proteins, while the high dose of 17.
Project description:The pollution of the environment with microplastics has been recognized as an emerging threat worldwide. Due to an exponential increase in production of plastic over the last eight decades and its longevity in the environment, accumulating amounts of microplastic are polluting rivers, lakes and the ocean. Their entry pathways are diverse and still only incompletely understood. Since microplastics are usually defined smaller than 5 mm, it can be ingested by a wide range of aquatic organisms including teleost fish. There are different approaches to study the detrimental effects of pollutants on aquatic organisms. On the one hand, generic baseline parameters such as growth and mortality are regularly considered, often accompanied by established stress parameters such as cortisol, heat shock proteins or lipid oxidation. The conflicting findings to date suggest that these parameters might not be sensitive enough to indicate the physiological effects of environmentally relevant microplastic concentrations. For this reason, more sophisticated biological approaches could provide new insights into whether and how microplastics harm fish. To date, proteomic approaches have been used only sporadically when investigating the effects of microplastic exposure on aquatic organisms. So far, this approach has not been used to address potential microplastic impacts in fish. In the present study, a proteomic approach was trialed alongside established methods in an investigation of fish experiencing long-term exposure to environmentally relevant concentrations of microplastics. Two groups of rainbow trout (Oncorhynchus mykiss were exposed to microplastic concentrations and sizes currently encountered in wild fish and an increased concentration, expected to occur in the near future. These groups where compared to a control group maintained in MP free conditions. Five fish of each treatment were sampled at three time points (week 1, week 4, week 17). The experiments were performed in triplicates, resulting in 45 samples used in the proteomic analysis.