A novel category of major intrinsic proteins which share weak similarities with previously identified aquaporin subfamilies was recently identified in land plants, and named X (for unrecognized) intrinsic proteins (XIPs). Because XIPs are still ranked as uncharacterized proteins, their further molecular characterization is required. Herein, a systematic fine-scale analysis of XIP sequences found in flowering plant databases revealed that XIPs are found in at least five groups. The phylogenetic relationship of these five groups with the phylogenetic organization of angiosperms revealed an original pattern of evolution for the XIP subfamily through distinct angiosperm taxon-specific clades. Of all flowering plant having XIPs, the genus Populus encompasses the broadest panel and the highest polymorphism of XIP isoforms, with nine PtXIP sequences distributed within three XIP groups. Comprehensive PtXIP gene expression patterns showed that only two isoforms (PtXIP2;1 and PtXIP3;2) were transcribed in vegetative tissues. However, their patterns are contrasted, PtXIP2;1 was ubiquitously accumulated whereas PtXIP3;2 was predominantly detected in wood and to a lesser extent in roots. Furthermore, only PtXIP2;1 exhibited a differential expression in leaves and stems of drought-, salicylic acid-, or wounding-challenged plants. Unexpectedly, the PtXIPs displayed different abilities to alter water transport upon expression in Xenopus laevis oocytes. PtXIP2;1 and PtXIP3;3 transported water while other PtXIPs did not.

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To cite this version:Manhattan Lebrun, Carmelo Macri, Florie Miard, Nour Hattab-Hambli, Mikael Motelica-Heino, et al.. Effect of biochar amendments on As and Pb mobility and phytoavailability in contaminated mine technosols phytoremediated by Salix. Journal of Geochemical Exploration, Elsevier, 2017Elsevier, , 182, pp.149-156. <10.1016Elsevier, /j.gexplo.2016 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Mining activities lead to widespread environmental pollution of terrestrial ecosystems due to the presence of metal(loid)s in tailings. These contaminated areas present a health risk and hence need to be rehabilitated. Ex situ methods for soil remediation have been used for a long time but are expensive and disruptive to soil. Phytoremediation techniques for the stabilization or extraction of metal(loid)s could be an efficient alternative as they provide a low-cost and environmentally friendly option. A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPTHowever, due to the often poor nutrient content of these contaminated soils, amendments must be added to enhance plant growth and to improve phytoremediation efficiency. Biochar, a pyrogenic product, is a promising amendment for assisted phytoremediation. The aims of our study were (i) to evaluate the effect of a pinewood biochar on the physicochemical properties of a former mine contaminated technosol, (ii) to assess the mobility and phytoavailability of As and Pb and (iii) to investigate the remediation potential of three willow species (Salix alba, Salix viminalis and Salix purpurea). A greenhouse experiment was conducted with contaminated technosols amended with biochar and garden soil, single or combined, revegetated with the 3 willow species. The physicochemical properties of soil pore water (SPW) as well as metal(loid) concentrations were determined. Plant growth, Salix organ dry weight and metal(loid) uptake were determined in order to evaluate the phytoremediation potential of the three Salix species studied. Biochar increased the pH and electrical conductivity of SPW. Biochar addition had no effect on As mobility but decreased SPW Pb concentration by 70%. For the three Salix species investigated, biochar addition to the polluted soil induced a better growth and a higher dry weight production. In most modalities tested, the metal(loid)A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPTcontent in the Salix organs increased due to the biochar application. Globally, a positive effect of biochar was noticed on the soil qualities (pH and electrical conductivity increase) and plant growth.Metal(loid)s were mostly confined to the roots. Amon...

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International audienceReclaiming degraded and contaminated soils with biochar amendments has become increasingly popular. Biochar, a fine-grained and porous biocarbon produced by the slow pyrolysis of biomass under oxygen limited conditions is foreseen as a possible solution to reduce metal(loid)s availability and phytotoxicity and simultaneously to improve the soil quality. Mining activities are one of the main concern generating potentially toxic elements (PTE) such as metal(loid)s-rich wastes and technosols. The effects of biochar addition (2% and 5%) on a former mine technosol characterized by high levels of PTE were investigated in laboratory during short-term experiments where technosols were potted and cultivated with dwarf beans (Phaseolus vulgaris L.) as indicator plants. Soil and soil pore water (SPW) physico-chemical properties were determined together with total dissolved concentrations of As, Sb and Pb in SPW sampled by Rhizons and available concentrations as measured by DGT (Diffusive Gradients in Thin-Films). Additionally indicator plant biomass and PTE concentrations in their organs (roots, stem and leaves) were determined. The results of the present study indicate that addition of 2 and 5% biochar to contaminated technosols increased soil and SPW pH, electrical conductivity (EC) and soil water content (SWC), decreased the labile concentration of Pb while increasing the As and Sb solubility. Indicator plants cultivated on biochar amended mine technosols showed a smaller biomass and higher PTE concentration levels in the various organs

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The reducing sugar of an oligosaccharide reacting with the alpha-amino group of an amino acid is converted to an N-oligosaccharylamino acid which can then be stabilized by N-acylation. Oligosaccharides in solution in N,N-dimethylformamide reacted with alpha-glutamyl-p-nitroanilide at 50 degrees C for a few hours, leading to an N-oligosaccharylglutamyl-p-nitroanilide. Then, the gamma-carboxylic group of the glutamyl moiety, activated by adding (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP), reacted with the substituted alpha-amino group of the glutamyl residue, leading to an N-oligosaccharylpyroglutamyl-p-nitroanilide within 0.5 h. Such a one-pot two-step reaction was shown to be very efficient in the case of a disaccharide such as lactose, or pentasaccharides such as lacto-N-fucopentaoses, Lewis(a) or Lewis(x). The glycosynthons were characterized by chromatography (HPAEC and HPLC); their molecular mass was determined by electrospray ionization mass spectrometry, and the glycosylamides were shown to have a beta-anomeric configuration on the basis of their proton NMR. The N-oligosaccharylpyroglutamyl-p-nitroanilides are quite stable at room temperature over a large pH range. They are easily converted to N-oligosaccharylpyroglutamyl-p-isothiocyanatoanilides which can be used to prepare glycoconjugates such as cationic glycosylated polylysines suitable for specifically delivering genes or oligonucleotides in a sugar-dependent manner.

International audienceIt is becoming increasingly popular to use phytoremediation methods for the reclamation of mine sites containing metal(loid)s. This study aims to assess the phytostabilization ability of two willow species (Salix viminalis and Salix purpurea) on technosols from a former gold mining site presenting polymetallic contamination (As, Sb and Pb). Different reconstituted soils using a mixture of the litter and the technosol collected on this previously mined site and a non-contaminated control garden soil were investigated in a 2 laboratory mesocosm. The physico-chemical soil parameters and the total metal(loid)s content in pore water were determined. After 45 days of growth, roots, leaves and stems from the two willow species were harvested. The biomass, metal(loid) concentrations and the mineral mass were determined for the different plant organs. Both Salix species were able to develop root systems on the different reconstituted soils and a variable aboveground biomass according to the soil composition. As, Sb and Pb accumulated mainly in the Salix rhizosphere. S. purpurea was more efficient in accumulating As in the plant's upper parts than S. viminalis. S. viminalis showed an ability to transfer Pb and Sb to its shoots whereas S. purpurea did not translocate these elements