Climate changes and environmental contaminants are daunting challenges that require an urgent change from current agricultural practices to sustainable agriculture. Biostimulants are natural solutions that adhere to the principles of organic farming and are believed to have low impacts on the environment and human health. Further, they may contribute to reducing the use of chemical inputs while maintaining productivity in adverse environments.
View Article and Find Full Text PDFThe production of biologics in mammalian cells is hindered by some limitations including high production costs, prompting the exploration of other alternative expression systems that are cheaper and sustainable like microalgae. Successful productions of biologics such as monoclonal antibodies have already been demonstrated in the diatom ; however, limited production yields still remain compared to mammalian cells. Therefore, efforts are needed to make this microalga more competitive as a cell biofactory.
View Article and Find Full Text PDFLaminarans are of interest because they have been shown to induce various immune responses in animals and plants. These β-D-glucans differ from each other by their branching rate, which is possibly responsible for their biological activities. In the present study, we characterized a laminaran fraction extracted from and named LAM2 using sugar composition and structural analyses (NMR).
View Article and Find Full Text PDFThere is a growing demand for molecules of natural origin for biocontrol and biostimulation, given the current trend away from synthetic chemical products. Leachates extracted from plantain stems were obtained after biodegradation of the plant material. To characterize the leachate, quantitative determinations of nitrogen, carbon, phosphorus, and cations (K, Ca, Mg, Na), Q2/4, Q2/6, and Q4/6 absorbance ratios, and metabolomic analysis were carried out.
View Article and Find Full Text PDFNowadays, many products are available in the plant biostimulants market. Among them, living yeast-based biostimulants are also commercialized. Given the living aspect of these last products, the reproducibility of their effects should be investigated to ensure end-users' confidence.
View Article and Find Full Text PDFThe root extracellular trap (RET) consists of root-associated, cap-derived cells (root AC-DCs) and their mucilaginous secretions, and forms a structure around the root tip that protects against biotic and abiotic stresses. However, there is little information concerning the changes undergone by the RET during droughts, especially for tree species. Morphological and immunocytochemical approaches were used to study the RET of black poplar ( L.
View Article and Find Full Text PDFThe root extracellular trap (RET) has emerged as a specialized compartment consisting of root AC-DC and mucilage. However, the RET's contribution to plant defense is still poorly understood. While the roles of polysaccharides and glycoproteins secreted by root AC-DC have started to be elucidated, how the low-molecular-weight exudates of the RET contribute to root defense is poorly known.
View Article and Find Full Text PDFProtein tracking in living plant cells has become routine with the emergence of reporter genes encoding fluorescent tags. Unfortunately, this imaging strategy is not applicable to glycans because they are not directly encoded by the genome. Indeed, complex glycans result from sequential additions and/or removals of monosaccharides by the glycosyltransferases and glycosidases of the cell's biosynthetic machinery.
View Article and Find Full Text PDFAphanomyces euteiches is an oomycete pathogen that causes the pea root rot. We investigated the potential role of early belowground defense in pea (susceptible plant) and faba bean (tolerant plant) at three days after inoculation. Pea and faba bean were inoculated with A.
View Article and Find Full Text PDFEndogenous viruses form an important proportion of eukaryote genomes and a source of novel functions. How large DNA viruses integrated into a genome evolve when they confer a benefit to their host, however, remains unknown. Bracoviruses are essential for the parasitism success of parasitoid wasps, into whose genomes they integrated ~103 million years ago.
View Article and Find Full Text PDFexDNA is found in various organisms, including plants. However, plant exDNA has thus far received little attention related to its origin and role in the RET (root extracellular trap). In this study, we performed the first high-throughput genomic sequencing of plant exDNA from a with worldwide interest: soybean ( (L.
View Article and Find Full Text PDFAnts use venom for predation, defense, and communication; however, the molecular diversity, function, and potential applications of ant venom remains understudied compared to other venomous lineages such as arachnids, snakes and cone snails. In this work, we used a multidisciplinary approach that encompassed field work, proteomics, sequencing, chemical synthesis, structural analysis, molecular modeling, stability studies, and and bioassays to investigate the molecular diversity of the venom of the Amazonian ants. We isolated a potent insecticidal heterodimeric peptide Δ-pseudomyrmecitoxin-Pp1a (Δ-PSDTX-Pp1a) composed of a 27-residue long A-chain and a 33-residue long B-chain cross-linked by two disulfide bonds in an antiparallel orientation.
View Article and Find Full Text PDFRoot border cells (BCs) and their associated secretions form a protective structure termed the root extracellular trap (RET) that plays a major role in root interactions with soil borne microorganisms. In this study, we investigated the release and morphology of BCs of using light and cryo-scanning electron microscopy (SEM). We also examined the occurrence of cell-wall glycomolecules in BCs and secreted mucilage using immunofluorescence microscopy in conjunction with anti-glycan antibodies.
View Article and Find Full Text PDFThis study presents a novel three-dimensional (3D) tool "3D choice" for chemotaxis assays with cyst nematodes. The original 3D choice was customized through digital printing. Freshly hatched second stage juveniles (J2s) of the cyst nematode were used as the nematode model to illustrate chemo-orientation behavior in the 3D system.
View Article and Find Full Text PDFBis(2-ethylhexyl) phthalate (DEHP) is a widely produced plasticizer that is considered to act as an endocrine-disrupting chemical in vertebrates and invertebrates. Indeed, many studies have shown that DEHP alters hormonal levels, reproduction and behavior in vertebrates. Few studies have focused on the effects of DEHP on insects, although DEHP is found almost everywhere in their natural habitats, particularly in soils and plants.
View Article and Find Full Text PDFArabinogalactan protein content in both root extracellular trap and root exudates varies in three Sahelian woody plant species that are differentially tolerant to drought. At the root tip, mature root cap cells, mainly border cells (BCs)/border-like cells (BLCs) and their associated mucilage, form a web-like structure known as the "Root Extracellular Trap" (RET). Although the RET along with the entire suite of root exudates are known to influence rhizosphere function, their features in woody species is poorly documented.
View Article and Find Full Text PDFNatural products have proven to be an immeasurable source of bioactive compounds. The exceptional biodiversity encountered in Amazonia, alongside a rich entomofauna and frequent interactions with various herbivores is the crucible of a promising chemodiversity. This prompted us to search for novel botanical insecticides in French Guiana.
View Article and Find Full Text PDFEndocrine-disrupting chemicals encompass a variety of chemicals that may interfere with the endocrine system and produce negative effects on organisms. Among them, bisphenol A is considered a major pollutant in numerous countries. The harmful effects of BPA on environmental and human health are intensely studied.
View Article and Find Full Text PDFThe root cap releases cells that produce massive amounts of mucilage containing polysaccharides, proteoglycans, extracellular DNA (exDNA) and a variety of antimicrobial compounds. The released cells - known as border cells or border-like cells - and mucilage secretions form networks that are defined as root extracellular traps (RETs). RETs are important players in root immunity.
View Article and Find Full Text PDFPea (Pisum sativum) root cap releases a large number of living border cells that secrete abundant mucilage into the extracellular medium. Mucilage contains a complex mixture of polysaccharides, proteins and secondary metabolites important for its structure and function in defense. Unlike xyloglucan and cellulose, pectin and arabinogalactan proteins have been investigated in pea root and shown to be major components of border cell walls and mucilage.
View Article and Find Full Text PDFDi (2-ethylhexyl) phthalate (DEHP) is recognized in vertebrates as an Endocrine Disrupting Chemical (EDC). DEHP can alter steroid hormones production, development, reproduction and behavior in vertebrates. Only few studies investigated DEHP effects on insects.
View Article and Find Full Text PDFExtensins are cell wall glycoproteins, belonging to the hydroxyproline-rich glycoprotein (HRGP) family, which are involved in many biological functions, including plant growth and defence. Several reviews have described the involvement of HRGPs in plant immunity but little focus has been given specifically to cell wall extensins. Yet, a large set of recently published data indicates that extensins play an important role in plant protection, especially in root-microbe interactions.
View Article and Find Full Text PDFEmergence of polyphagous herbivorous insects entails significant adaptation to recognize, detoxify and digest a variety of host-plants. Despite of its biological and practical importance - since insects eat 20% of crops - no exhaustive analysis of gene repertoires required for adaptations in generalist insect herbivores has previously been performed. The noctuid moth Spodoptera frugiperda ranks as one of the world's worst agricultural pests.
View Article and Find Full Text PDFFour new sesquiterpene alkaloids (1-4) with a β-dihydroagrofuran skeleton and a new triterpenoid (5) were isolated from an ethyl acetate extract of Maytenus oblongata stems. Their structures were elucidated using 1D and 2D NMR spectroscopy as well as MS and ECD experiments. The M.
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