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Devime, F.

Publications and source records attributed to Devime, F..

2 recordsLinked to original sources
bioRxiv2023

Characterization of a uranium-tolerant green microalga of the genus Coelastrella with high potential for the remediation of metal-polluted waters

Uranium (U) pollution of terrestrial and aquatic ecosystems poses a significant threat to the environment and human health because this radionuclide is chemotoxic. Characterization of organisms that tolerate and accumulate U is critical to decipher the mechanisms evolved to cope with the radionuclide and to propose new effective strategies for bioremediation of U-contaminated environments. Here, we isolated a unicellular green microalga of the genus Coelastrella from U-contaminated wastewater. We showed that Coelastrella sp. PCV is much more tolerant to U than Chlamydomonas reinhardtii and Chlorella vulgaris. Coelastrella is able to accumulate U very rapidly, then gradually release it into the medium, behaving as an excluder to limit the toxic effects of U. The ability of Coelastrella to accumulate U is remarkably high, with up to 600 mg U sorbed per g dry biomass. Coelastrella is able to grow and maintain high photosynthesis in natural metal-contaminated waters from a wetland near a reclaimed U mine. Over a single one-week growth cycle, Coelastrella is able to capture 25-55% of U from contaminated waters and demonstrates lipid droplet accumulation. Coelastrella sp. PCV is a very promising microalga for the remediation of polluted waters with valorization of algal biomass that accumulates lipids. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=176 SRC="FIGDIR/small/546994v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@1ff356corg.highwire.dtl.DTLVardef@c53d0org.highwire.dtl.DTLVardef@15284eborg.highwire.dtl.DTLVardef@946d49_HPS_FORMAT_FIGEXP M_FIG C_FIG

plant biology↗
bioRxiv2021

Calcium-permeable cation channels are involved in uranium uptake in Arabidopsis thaliana

Uranium (U) is a non-essential and toxic element that is taken up by plants from the environment. The assimilation pathway of U is still unknown in plants and any other organism. In this study, we provide several evidences that U is taken up by the roots of Arabidopsis thaliana through Ca2+-permeable cation channels. First, we showed that deprivation of Arabidopsis plants with calcium induced a 1.5-fold increase in the capacity of roots to accumulate U, suggesting that calcium deficiency promoted the radionuclide import pathway. Second, we showed that external calcium inhibits U accumulation in roots, suggesting a common route for the uptake of both cations. Third, we found that gadolinium, nifedipine and verapamil inhibit the absorption of U, suggesting that different types of Ca2+-permeable channels serve as a route for U uptake. Last, we showed that U bioaccumulation in Arabidopsis mutants deficient for the Ca2+-permeable channels MCA1 and ANN1 was decreased by 40%. This suggests that MCA1 and ANN1 contribute to the absorption of U in different zones and cell layers of the root. Together, our results describe for the first time the involvement of Ca2+-permeable cation channels in the cellular uptake of U.

plant biology↗