Project description:Per- and polyfluoroalkyl Substances (PFAS) – the so-called ‘forever chemicals’ – are a major cause of environmental and health concern due to their toxicity and long-term persistence1,2. Yet, no efficient mechanisms for their removal have been identified. Here we report bioaccumulation of PFAS by several gut bacterial species over a wide range of concentrations from nanomolar up to 500 μM. For bioaccumulating Bacteroides uniformis, a highly prevalent species, we estimate intracellular PFAS concentration in the mM range – above that of most native metabolites. Despite this high bioaccumulation, B. uniformis cells could grow appreciably up to 250 μM perfluorononanoic acid (PFNA) exposure. Escherichia coli, which accumulated PFAS to a much lesser extent, substantially increased PFAS bioaccumulation when lacking TolC efflux pump indicating trans-membrane transport in PFAS bioaccumulation. Electron microscopy and cryogenic Focused Ion Beam-Secondary Ion Massspectrometry revealed distinct morphological changes and intracellular localisation of PFNA aggregates. Bioaccumulation of PFAS and transmembrane transport is also evident in proteomics, metabolomics, thermal proteome profiling, and mutations following adaptive laboratory evolution. In an in vivo context, mice colonized with human gut bacteria showed, compared to germ-free controls or those colonized with low-bioaccumulating bacteria, higher PFNA levels in excreted feces. As the gut microbiota is a critical interface between exposure and human body, our results have implications for understanding and utilizing microbial contribution to PFAS clearance.
Project description:Poison frogs sequester chemical defenses from their diet of leaf litter arthropods for defense against predation. Little is known about the physiological adaptations that confer this unusual bioaccumulation ability. We conducted an alkaloid-feeding experiment with the Diablito poison frog (Oophaga sylvatica) to determine how quickly alkaloids are accumulated and how toxins modify frog physiology using quantitative proteomics. Diablito frogs rapidly accumulated the alkaloid decahydroquinoline within four days, and dietary alkaloid exposure modified protein abundance in the intestines, liver, and skin. Many proteins that increased in abundance with toxin accumulation are plasma glycoproteins, including the complement system and the toxin-binding protein saxiphilin. Other protein classes that change in abundance with toxin accumulation are membrane proteins involved in small molecule transport and metabolism. Overall, this work shows poison frogs can rapidly accumulate alkaloids, which alter carrier protein abundance, initiate an immune response, and alter small molecule transport and metabolism dynamics across tissues
2021-01-25 | PXD021216 | Pride
Project description:Evaluation of heavy metal bioaccumulation, growth, and root microbial community in hemp
Project description:Polychlorinated diphenyl ethers are lipophilic, persistent, and bioaccumulable compounds widely used as flame-retardants. These are chemicals of increasing environmental concern due to their lipophilic, persistent, and bioaccumulable characteristics. The objective of this study was to analyze the potential bioavailability and bioaccumulation of BDE-209 as a source of toxicity. Zebrafish embryos were exposed for 8 days to sediments spiked with an environmentally relevant concentration of BDE-209. We analyzed gene expression changes, thyroid function, and several markers for neurotoxicity. Results of this research highlight the need to consider the capability of BDE-209 to be bioavailable and bioaccumulate, indicating the potential hazardous effects.
2013-01-01 | GSE39169 | GEO
Project description:Bioaccumulation of heavy metals by Thiopseudomonas alkaliphila isolated from industrial sites of Bengaluru
Project description:Poly- and perfluorinated alkyl substances (PFAS) are a group of persistent organic pollutants. Plants can accumulate PFAS but their effect on plant physiology at the molecular level is not understood yet. We used hydroponically-grown maize plants treated with a combination of eleven different PFAS (each at 100 µg L-1) to investigate their bioaccumulation and effects on the growth, physiology and their impact on the root proteome. From the root proteome analysis, we identified 75 differentially abundant proteins, mostly involved in cellular metabolic and biosynthetic processes, translation and cytoskeletal reorganization. Results were validated using quantitative real-time PCR and further substantiated using amino acid and fatty acid profiling.