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International audience; Lactococcus cremoris and Lactococcus lactis are among the most extensively exploited species of lactic acid bacteria in dairy fermentations. The cell wall of lactococci, like other Gram-positive bacteria, possesses a thick peptidoglycan layer, which may incorporate cell wall polysaccharides (CWPS), wall teichoic acids (WTA), and/or lipoteichoic acids (LTA).In this study, we report the isolation, purification and structural analysis of the carbohydrate moieties of glycolipids (GL) and LTA of the L. cremoris model strain 3107. Chemical structures of these compounds were studied by chemical methods, NMR spectroscopy and positive and negative mode ESI MS. We found that the LTA of strain 3107 is composed of short chains of 1,3-polyglycerol phosphate (PGP), attached to O-6 of the non-reducing glucose of the kojibiose-Gro backbone of the glycolipid anchor. Extraction of cells with cold TCA afforded the detection of 1,3-glycerol phosphate chains randomly substituted at O-2 of glycerol by D-Ala. Unlike the LTA of L. lactis strains studied to date, the PGP backbone of the LTA of L. cremoris 3107 did not carry any glycosyl substitution. The deacylated glycolipid fraction contained the free kojibiose-Gro oligosaccharide, identical to the backbone of the GL anchor of LTA, and its shorter fragment α-Glc-1-Gro. These OS may have originated from the GL precursors of LTA biosynthesis.

International audience; Emergence of secondary roots through parental tissue is a highly controlled developmental process. Although the model plant Arabidopsis has been useful to uncover the predominant role of auxin in this process, its simple root structure is not representative of how emergence takes place in most plants, which display more complex root anatomy. White lupin is a legume crop producing structures called cluster roots, where closely spaced rootlets emerge synchronously. Rootlet primordia push their way through several cortical cell layers while maintaining the parent root integrity, reflecting more generally the lateral root emergence process in most multilayered species. In this study, we showed that lupin rootlet emergence is associated with an upregulation of cell wall pectin modifying and degrading genes under the active control of auxin. Among them, we identified LaPG3, a polygalacturonase gene typically expressed in cells surrounding the rootlet primordium and we showed that its downregulation delays emergence. Immunolabeling of pectin epitopes and their quantification uncovered a gradual pectin demethylesterification in the emergence zone, which was further enhanced by auxin treatment, revealing a direct hormonal control of cell wall properties. We also report rhamnogalacturonan-I modifications affecting cortical cells that undergo separation as a consequence of primordium outgrowth. In conclusion, we describe a model of how external tissues in front of rootlet primordia display cell wall modifications to allow for the passage of newly formed rootlets.

International audience; The pretreatment of Miscanthus x giganteus with the ionic liquid 1-ethyl-3-methylimidazolium acetate ([Emim] [OAc]), followed by enzymatic hydrolysis and oxidative depolymerization, resulted in the efficient production of monomeric sugars and selective production of phenolic intermediates. The liquid fractions containing monomeric sugars were obtained with high yields (>80%), while a solid fraction enriched with lignin (>50% w.w − 1) was isolated. The phenolic monomers released during [Emim][OAc]-pretreatment were identified and quantified by HPLC. A decrease in the content of vanillin, vanillic acid, and p-hydroxybenzaldehyde was observed during pretreatment, suggesting a selective solubilization of guaicyl and p-hydroxyphenyl units from the lignin polymer in [Emim][OAc]. The decrease in p-coumaric and ferulic acids content suggested a cleavage of lignincarbohydrate complexes during pretreatment. Both pretreatment and enzymatic hydrolysis affected the content of ferulic acid ether and ester bonds. The NMR structural study (2D HSQC) of the isolated lignin showed the preservation of β-O-4 ′ interunit bonds, while 31 P NMR analysis revealed a high content of aliphatic hydroxyl groups. The oxidative depolymerization of the isolated lignin, catalyzed by the laccase mediator system in the presence of 5% v.v − 1 recycled [Emim][OAc] in buffer, mainly led to the production of free p-hydroxybenzaldehyde as a promising platform molecule. The mass balance of glucan, xylan and lignin from Miscanthus was validated throughout this strategy.

International audience; In the past decades, the microencapsulation of mammalian cells into microparticles has been extensively studied for various in vitro and in vivo applications. The aim of this study was to demonstrate the viability of bacterial polyglucuronic acid (PGU), an exopolysaccharide derived from bacteria and composed of glucuronic acid units, as an effective material for cell microencapsulation. Using the method of dropping an aqueous solution of PGU-containing cells into a Ca2+-loaded solution, we produced spherical PGU microbeads with >93 % viability in the encapsulated human hepatoma HepG2 cells. Hollow-core microcapsules were formed via polyelectrolyte complex layer formation of PGU and poly-l-lysine, after which Ca2+, a cross-linker of PGU, was chelated, and this was accomplished by sequential immersion of microbeads in aqueous solutions of poly-l-lysine and sodium citrate. The encapsulated HepG2 cells proliferated and formed cell aggregates within the microparticles over a 14-day culture, with significantly larger aggregates forming within the microcapsules. Our results provide evidence for the viability of PGU for cell microencapsulation for the first time, thereby contributing to advancements in tissue engineering.

Most organisms adjust their development according to the environmental conditions. For the majority, this implies the sensing of alterations to cell walls caused by different cues. Despite the relevance of this process, few molecular players involved in cell wall sensing are known and characterized. Here, we show that the wall-associated kinase-like protein RESISTANCE TO FUSARIUM OXYSPORUM 1 (RFO1) is required for plant growth and early defense against Fusarium oxysporum and functions by sensing changes in the pectin methylation levels in the cell wall. The RFO1 dwell time at the plasma membrane is affected by the pectin methylation status at the cell wall, regulating MITOGEN-ACTIVATED PROTEIN KINASE and gene expression. We show that the extracellular domain of RFO1 binds de-methylated pectin in vitro, whose distribution in the cell wall is altered during F. oxysporum infection. Further analyses also indicate that RFO1 is required for the BR-dependent plant growth alteration in response to inhibition of pectin de-methyl-esterase activity at the cell wall. Collectively, our work demonstrates that RFO1 is a sensor of the pectin methylation status that plays a unique dual role in plant growth and defense against vascular pathogens., Molecular Plant, 16 (5), ISSN:1752-9867, ISSN:1674-2052

International audience; Baillonella toxisperma is a medicinal plant used in northern Gabon to treat microbial diseases. It is a plant well-known by local populations, but very few studies have focused on the molecules responsible for the antibacterial activities of B. toxisperma. This study proposes a dereplication strategy based on molecular networking generated from HPLC-ESI-Q/TOF data, allowing investigation of the molecules responsible for the antibacterial activity of B. toxisperma. From this strategy, eighteen compounds were putatively identified. All of these compounds belonged mainly to five families of natural compounds, including phenylpropanolamines, stilbenes, flavonoids, lignans and phenolic glycosides. The chemical study carried out from the bark of B. toxisperma allowed us to identify, for the first time, compounds such as resveratrol and derivatives, epicatechin, epigallocatechin and epigallocatechin gallate. In addition, antibacterial activity (diffusion method and microdilution) and cytotoxicity (Cell Counting Kit-8 (CCK-8 Assay)) in vitro were evaluated. The crude ethanolic extract, as well as the fractions of B. toxisperma, showed significant antibacterial activity. However, the ethanolic fractions F2 and F4 presented high antibacterial activity compared to the crude extract. Cytotoxicity studies on colon-cancer cells (Caco-2) and human keratinocyte cells (HaCaT) showed moderate cytotoxicity in both cell types. This study clearly shows the therapeutic potential of the ethanolic extract of the bark of B. toxisperma and provides information on the phytochemical composition and bioactive compounds of the plant.

The aim of this study was to identify the chemical composition and sequential structure of alginate isolated from C. crinita harvested in the Bulgarian Black Sea, as well as its effects in histamine-induced paw inflammation in rats. The serum levels of TNF-α, IL-1β, IL-6, and IL-10 in rats with systemic inflammation, and the levels of TNF-α in a model of acute peritonitis in rats were also investigated. The structural characterization of the polysaccharide was obtained by FTIR, SEC-MALS, and 1H NMR. The extracted alginate had an M/G ratio of 1.018, a molecular weight of 7.31 × 104 g/mol, and a polydispersity index of 1.38. C. crinita alginate in doses of 25 and 100 mg/kg showed well-defined anti-inflammatory activity in the model of paw edema. A significant decrease in serum levels of IL-1β was observed only in animals treated with C. crinita alginate in a dose of 25 mg/kg bw. The concentrations of TNF-α and IL-6 in serum were significantly reduced in rats treated with both doses of the polysaccharide, but no statistical significance was observed in the levels of the anti-inflammatory cytokine IL-10. A single dose of alginate did not significantly alter the levels of the pro-inflammatory cytokine TNF-α in the peritoneal fluid of rats with a model of peritonitis.

International audience; Colorectal cancer (CRC) is one of the most common cancers in the world. When treating patients, therapeutic agents have side effects; hence, the use of natural compounds found in medicinal plants including pomegranate. Ultrasound assisted extraction (UAE) is a new technique evolving to the detriment of traditional methods such as maceration. In this study, we investigated the antioxidant and anticancer effect of pomegranate peel extracts obtained by maceration and UAE at three different ultrasonic power levels (P1 = 10 W; P2 = 50 W; P3 = 100 W) on HCT-116 colorectal cancer cells. Phytochemical screening highlighted the presence of primary and secondary metabolites in pomegranate peels. In addition, the ethanolic extract obtained by UAE at 50 W was shown to be the most concentrated in phenolic and flavonoid compounds and have the most powerful antioxidant activity, which reached a maximum activity of 92% as determined by DPPH test. Similarly, the MTT cell viability test showed that the extract obtained by UAE at 50 W had the most potent inhibitory effect compared to the other extracts. In conclusion, the UAE at 50 W was shown to be the most suitable and efficient extraction technique to obtain bioactive compounds from pomegranate peel extracts that can be used in the treatment of CRC.

International audience; Laurus nobilis belongs to the family Lauraceae and is characterized by its evergreen nature. It is well known because of its traditional use in cooking and folk medicine. Many studies have been performed regarding its chemical composition and the pharmacological potential it exhibits. It has been reported to have antioxidant, antibacterial, antifungal, antiviral, biocidal, antidiabetic, antiulcerogenic, neuroprotective, analgesic, anti-inflammatory, and anticholinergic properties, making this plant of great clinical importance. The main chemical compounds that show bioactive properties in L. nobilis are terpenoids, phenolics, and fatty acids. The purpose of this review is to describe the main use of L. nobilis, notably of the leaves and fruits, and to relate their metabolite content with their pharmacological and toxicological properties.

International audience; Botryosphaeria dieback is a grapevine trunk disease that affects all viticulture regions of the world. Species of the genus Lasiodiplodia have been reported as pathogenic towards grapevine in several growing regions and have also been previously reported from Portuguese vineyards. Species in this genus, particularly Lasiodiplodia theobromae, have been reported on previous studies to be more aggressive than other Botryosphaeriaceae species most commonly associated with Botryosphaeria dieback. The aim of this study was to assess the response of some of the more representative cultivars planted throughout Portuguese vineyards, Touriga Nacional, Touriga Franca, Alvarinho, Aragonez (=Tempranillo) and Cabernet Sauvignon, by performing artificial inoculations with Lasiodiplodia spp. collected in different geographic locations worldwide. Two experiments, one by inoculating two-year-old grapevines kept on a greenhouse-controlled conditions with six isolates of L. theobromae and one isolate of L. mediterranea and other by inoculating seven-year-old field grown grapevines with two isolates of L. theobromae, were conducted twice. Response of the cultivars was assessed by evaluating the lesion length caused by the isolates under study, five months after inoculation. The results showed that all isolates studied were able to infect the annual shoots since they were always re-isolated and produced internal wood discoloration. Significant differences were found for all isolate/cultivar combinations. For both experiments, Touriga Nacional showed the largest lesions while Aragonez recorded the smallest lesions amongst the whole lot of cultivars inoculated with Lasiodiplodia spp.. In general, Portuguese isolates were more aggressive than those from Peru, which demonstrated to be mildly aggressive. These results give a first insight on the response of selected Portuguese cultivars to Lasiodiplodia species, which are present in Portugal, but not commonly associated with Botryosphaeria dieback. This contributes to improve knowledge of the impact that Botryosphaeria dieback causal agents have on crucial national cultivars, which may help winegrowers not only to manage current cultural practices, but also to optimize decision making when planning the establishment of new vineyards.

(1) Background: Many human diseases are associated with oxidative stress, which is caused by reactive oxygen species and free radicals generated in living cells. Some biomass extracts derived from various types of plants can act as efficient drugs against pathological disorders related to oxidative stress. Numerous herbal blends have thus been shown to improve health. Cleistocalyx operculatus (Roxb.) Merr. and L.M.Perry teas have been considered in that way. Problem: Because of amertume, the taste of C. operculatus avoids or limits a large use of such alleged healthy leaf infusions. (2) Methods: The phytochemistry, oxygen, free radical scavenging activity, and antilipid peroxidation of C. operculatus teas were here studied in vitro. Then different mixes of C. operculatus and Mentha arvensis were infused together and tasted in a hedonic test. The chemical and biological properties of the best mix were then analyzed. (3) Results: The herbal blend of C. operculatus revealed significant scavenging effects on 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) with IC50 values of 35.6 µg/mL. Induced by hydroxyl radicals, this beverage could significantly inhibit the lipid peroxidation of mouse brain homogenates. Our results demonstrate that the lipid peroxidation inhibition of dried leaves of C. operculatus might be related to its scavenging effects on oxygen free radicals. This C. operculatus bitter blend was then combined with various amounts of M. arvensis Linn. The taste was evaluated, and further biochemical analyses were conducted on the best 7/3 ratio. They showed that the healthy properties were maintained. (4) Conclusion: The optimized 7/3 ratio of the Cleistocalyx/Mentha mix led to the best results in terms of taste (sensory tests). It is demonstrated that the potential health benefits against oxidative stress remained high as compared with pure C. operculatus infusion.

Pistacia lentiscus L. is a medicinal plant that grows spontaneously throughout the Mediterranean basin and is traditionally used to treat diseases, including diabetes. The aim of this work consists of the evaluation of the α-glucosidase inhibitory effect (i.e., antidiabetic activity in vitro) of different extracts from the leaves, stem barks and fruits of P. lentiscus harvested on mountains and the littoral of Tizi-Ouzou in Algeria. Metabolomic profiling combined with a chemometric approach highlighted the variation of the antidiabetic properties of P. lentiscus according to the plant’s part and origin. A multiblock OPLS analysis showed that the metabolites most involved in α-glucosidase inhibition activity were mainly found in the stem bark extracts. The highest inhibitory activity was found for the stem bark extracts, with averaged inhibition percentage values of 84.7% and 69.9% for the harvested samples from the littoral and mountain, respectively. On the other hand, the fruit extracts showed a lower effect (13.6%) at both locations. The UHPLC-ESI-HRMS characterization of the metabolites most likely responsible for the α-glucosidase-inhibitory activity allowed the identification of six compounds: epigallocatechin(4a>8)epigallocatechin (two isomers), (epi)gallocatechin-3′-O-galloyl-(epi)gallocatechin (two isomers), 3,5-O-digalloylquinic acid and dihydroxy benzoic acid pentoside.

International audience; The rapeseed crop is susceptible to many pathogens such as parasitic plants or fungi attacking aerial or root parts. Conventional plant protection products, used intensively in agriculture, have a negative impact on the environment as well as on human health. There is therefore a growing demand for the development of more planet-friendly alternative protection methods such as biocontrol compounds. Natural rhamnolipids (RLs) can be used as elicitors of plant defense mechanisms. These glycolipids, from bacteria secretome, are biodegradable, non-toxic and are known for their stimulating and protective effects, in particular on rapeseed against filamentous fungi. Characterizing the organ responsiveness to defense-stimulating compounds such as RLs is missing. This analysis is crucial in the frame of optimizing the effectiveness of RLs against various diseases. A Tandem Mass Tags (TMT) labeling of the proteins extracted from the shoots and roots of rapeseed has been performed and showed a differential pattern of protein abundance between them. Quantitative proteomic analysis highlighted the differential accumulation of parietal and cytoplasmic defense or stress proteins in response to RL treatments with a clear effect of the type of application (foliar spraying or root absorption). These results must be considered for further use of RLs to fight specific rapeseed pathogens.

Fish consumption in France has increased by 20% in 20 years, from 19.1 kg/inhabitant/year in 2000 to 23.9 kg/inhabitant/year in 2020. This increase leads to an overexploitation of traditional fishing areas that are no longer sufficient to supply the fresh market. To overcome this supply problem, the share of aquaculture has grown considerably over the last 20 years, from 25.7% to 46%. The exploitation of new fishing areas that are increasingly far from consumption sites is also another alternative to these supply shortages, which increases travel from fishing to consumer. As a consequence, fraudulent practices of selling frozen/thawed aquatic products in the fresh market often occur. The development of a reliable tool for distinguishing fresh and frozen/thawed products remains a major challenge for the seafood sector.The thesis aimed to explore the use of mitochondria as a marker of freshness and freezing of fish.Mitochondria are mostly present in red muscle tissue. Therefore, our study focused on this tissue for the three fish species studied: sea bass (Dicentrarchus labrax), gilthead sea bream (Sparus aurata) and rainbow trout (Oncorhynchus mykiss). We have found that freezing leads to profound structural changes in mitochondria, with an alteration of the outer and inner membranes (visible in electron microscopy). The alteration of mitochondrial membranes contributes to the total loss of mitochondrial potential of isolated mitochondria. This loss of potential was analyzed in flow cytometry using two potential probes: TMRM and Rhodamine 123. The loss of potential was observed on fresh fish fillet on Day 9, which limits the use of the loss of potential as a marker of freezing.Mitochondrial permeabilization by freezing/thawing shock was first studied by measuring the NADH permeability of isolated mitochondria. The level of permeabilization was normalized by comparison to permeabilization by a known channel-forming antibiotic alamethicin. This permeabilization was followed by the spectrophotometric measurement of the rate of consumption of NADH by mitochondria and the activation of oxygen consumption by oxygraphy. Freezing/thawing was shown to lead to NADH permeabilization of mitochondria and activation of enzyme complexes which results in increased oxygen consumption.The results obtained on isolated mitochondria were confirmed on entire muscle fibres, thus allowing to skip the mitochondrial extraction steps. Freezing leads to rupture of mitochondrial membranes and plasma membranes. Muscle fibres from frozen muscle are more permeable to NADH and therefore consume it faster than fresh fibres. A greater stimulation of oxygen consumption by thawed fibers was also observed.Maintaining a certain integrity of mitochondria in red muscle makes it possible to explore mitochondrial functions and use them as a marker for freezing/thawing fish fillets. This work showed that mitochondria isolated or present in the fibers of fresh fillets were sensitive to the action of a permeabilizer. Conversely, mitochondria and fibres isolated from frozen fillets were insensitive to alamethicin. This reflects a high level of alteration of mitochondrial membranes in these products. This technique, which uses red muscle, appears to be effective in discriminating between frozen aquatic products and fresh products. It is necessary to define whether it can be adapted to the white muscle of fish fillets.; La consommation de poisson en France a augmenté de 20 % en 20 ans, passant de 19,1 kg/hab/an en 2000 à 23,9 kg/hab/an en 2020. Cette hausse se traduit par une surexploitation de zones traditionnelles de pêche qui ne sont plus suffisantes pour alimenter le marché du frais. Pour pallier ce problème d’approvisionnement, la part de l’aquaculture s’est considérablement développée ces 20 dernières années en passant de 25,7 % à 46 %. L’exploitation de nouvelles zones de pêche de plus en plus éloignées des sites de consommation est aussi une autre alternative à ces problèmes d’approvisionnement.Si de nombreux produits aquatiques sont connus pour être commercialisés à l’état décongelé, l’alimentation du marché du frais par des produits décongelés constitue une fraude. La mise au point d’un outil fiable de détection des produits congelés/décongelés reste un enjeu majeur pour la filière des produits de la mer. Elle permettrait de détecter les fraudes, la congélation/décongélation pouvant entraîner des modifications au niveau du produit.La thèse avait pour but d’explorer l’utilisation des mitochondries comme marqueurs de fraîcheur et de décongélation. Les mitochondries sont particulièrement présentes dans le tissu musculaire rouge. C’est pourquoi notre étude s’est concentrée sur ce tissu pour les trois espèces de poissons étudiées : le bar (Dicentrarchus labrax), la daurade royale (Sparus aurata) et la truite arc en ciel (Oncorhynchus mykiss). La congélation va entraîner de profondes modifications structurales des mitochondries, avec une altération des membranes externes et internes (visible en microscopie électronique). L’altération des membranes mitochondriales va participer à la perte totale du potentiel mitochondrial des mitochondries isolées. Cette perte du potentiel a été analysée en cytométrie de flux grâce à deux sondes de potentiel : le TMRM et la Rhodamine 123. La perte de potentiel peut cependant être observée sur du filet de poisson frais à J9, ce qui limite l’utilisation de la perte du potentiel comme marqueur de décongélation.La perméabilisation des mitochondries par le choc congélation/décongélation a été étudiée en mesurant la perméabilité au NADH de mitochondries isolées. Le niveau de perméabilisation a été normalisé en utilisant un perméabilisant : l’alaméthicine. Cette perméabilisation a été suivie par la mesure de la vitesse de consommation du NADH par les mitochondries en spectrophotométrie et l’activation de la consommation de d’oxygène en oxygraphie. La congélation/décongélation conduit à une perméabilisation au NADH des mitochondries et à une activation des complexes enzymatiques qui se traduit par un regain de consommation d’oxygène.Pour s’affranchir des étapes d’extraction des mitochondries, ces résultats ont été confirmés sur fibres musculaires. La congélation entraîne une rupture des membranes mitochondriales et des membranes plasmiques. Les fibres musculaires issues du muscle décongelé sont plus perméables au NADH et le consomment donc plus rapidement que les fibres fraîches. Une stimulation plus importante de la consommation d’oxygène par les fibres décongelées est aussi observée.Le maintien d’une certaine intégrité des mitochondries dans le muscle rouge permet d’explorer les fonctions mitochondriales et de les utiliser comme marqueur de congélation/décongélation des filets de poisson. Ces travaux ont montré que les mitochondries isolées ou présentes dans les fibres de filets frais étaient sensibles à l’action d’un perméabilisant. A l‘inverse, les mitochondries et fibres isolées de filets décongelés étaient insensibles à l’alaméthicine. Ceci traduit un niveau élevé d’altération des membranes mitochondriales dans ces produits. Cette technique, qui utilise le muscle rouge, semble efficace pour discriminer les produits aquatiques décongelés des produits frais. Il reste à définir si celle-ci peut s’adapter au muscle blanc des filets de poisson.

Background The mid-term respiratory sequelae in survivors of severe COVID-19 appear highly heterogeneous. In addition, factors associated with respiratory sequelae are not known. In this monocentric prospective study, we performed a multidisciplinary assessment for respiratory and muscular impairment and psychological distress 3 months after severe COVID-19. We analysed factors associated with severe persistent respiratory impairment, amongst demographic, COVID-19 severity, and 3-month assessment. Methods Patients with severe SARS-CoV-2 pneumonia requiring ≥ 4L/min were included for a systematic 3-month visit, including respiratory assessment (symptoms, lung function, CT scan), muscular evaluation (body composition, physical function and activity, disability), psychopathological evaluation (anxiety, depression, post-traumatic stress disorder-PTSD) and quality of life. A cluster analysis was performed to identify subgroups of patients based on objective functional measurements: DLCO, total lung capacity and 6-min walking distance (6MWD). Results Sixty-two patients were analysed, 39% had dyspnea on exercise (mMRC ≥ 2), 72% had DLCO LCO 48 ± 12%, 6MWD 299 ± 141 m). This SP cluster was characterized by older age, severe respiratory symptoms, but also sarcopenia/pre-sarcopenia, symptoms of PTSD and markedly impaired quality of life. It was not associated with initial COVID-19 severity or management. Conclusions and clinical implication We identified a phenotype of patients with severe persistent respiratory and muscular impairment and psychological distress 3 months after severe COVID-19. Our results highlight the need for multidisciplinary assessment and management after severe SARS-CoV-2 pneumonia. Trial registration The study was registered on ClinicalTrials.gov (May 6, 2020): NCT04376840

Streptococcus thermophilus is present and applied in industrial and artisanal dairy fermentations for the production of various cheeses and yogurt. During these fermentations, S. thermophilus is vulnerable to phage predation, and recent studies have identified the rhamnose-glucose polymer (Rgp) as the definitive receptor for at least one problematic phage species.

The LysM receptor-like kinases (LysM-RLKs) play a crucial role in plant symbiosis and response to environmental stresses. Brassica napus, B. rapa, and B. oleracea are utilized as valuable vegetables. Different biotic and abiotic stressors affect these crops, resulting in yield losses. Therefore, genome-wide analysis of the LysM-RLK gene family was conducted. From the genome of the examined species, 33 LysM-RLK have been found. The conserved domains of Brassica LysM-RLKs were divided into three groups: LYK, LYP, and LysMn. In the BrassicaLysM-RLK gene family, only segmental duplication has occurred. The Ka/Ks ratio for the duplicated pair of genes was less than one indicating that the genes’ function had not changed over time. The BrassicaLysM-RLKs contain 70 cis-elements, indicating that they are involved in stress response. 39 miRNA molecules were responsible for the post-transcriptional regulation of 12 Brassica LysM-RLKs. A total of 22 SSR loci were discovered in 16 Brassica LysM-RLKs. According to RNA-seq data, the highest expression in response to biotic stresses was related to BnLYP6. According to the docking simulations, several residues in the active sites of BnLYP6 are in direct contact with the docked chitin and could be useful in future studies to develop pathogen-resistant B. napus. This research reveals comprehensive information that could lead to the identification of potential genes for Brassica species genetic manipulation.

International audience; The pomegranate fruit is made of white to deep purple seeds that are enclosed in a white, spongy, astringent membrane, also known as pericarp, covered by a thick red skin and a crown-shaped calyx. It contains a variety of beneficial ingredients, including flavonoids, ellagitannin, punicalagin, ellagic acid, vitamins, and minerals. Pomegranates possess numerous health benefits, and their use in disease treatment has been widely recognized since antiquity. This fruit was known to exhibit several biological properties, including antibacterial, anti-inflammatory, antioxidant, and anticancer activities. Pomegranate has been used in a variety of medical systems for the treatment and therapy of a wide range of diseases and illnesses. This review summarizes studies highlighting the potential role of pomegranate in the prevention and treatment of diseases related to respiratory and digestive systems.

International audience; The Mo/W-bisPGD enzyme superfamily comprises a vast number of mononuclear molybdenum and tungsten enzymes that catalyze a great diversity of vital reactions in prokaryotes. In the past decades, much attention has been devoted to the immediate surroundings of the metal atom highlighting the importance of the inner coordination sphere but has failed to identify molecular determinants of the reactivity. Here, we report the mechanistic importance of a set of conserved residues that line the substrate entry tunnel in Escherichia coli nitrate reductase A (Nar), a paradigmatic enzyme of the Mo/W-bisPGD superfamily. Using mutagenesis, enzyme kinetics, electron paramagnetic resonance spectroscopy, and molecular dynamics, we unveil the pivotal role of Glu-581 motion and a number of polar residues in its close proximity in substrate affinity and proton transfer to the Mo active site. Motion of the side chain of Glu-581 exhibiting a strong acid–base cooperativity with Asp-801 and surrounded by several polar interactions controls the hydration inside the protein core, proton transfer, and substrate selectivity toward the active site. Overall, we identify an additional determinant that fine-tunes the reactivity and selectivity in Nar and propose that a gating mechanism is at play in several other members of the superfamily.

Net blotch, caused by the ascomycete Drechslera teres, can compromise barley production. Beneficial bacteria strains are of substantial interest as biological agents for plant protection in agriculture. Belonging to the genus Paraburkholderia, a bacterium, referred to as strain B25, has been identified as protective for barley against net blotch. The strain Paraburkholderia phytofirmans (strain PsJN), which has no effect on the pathogen's growth, has been used as control. In this study, the expression of target genes involved in cell wall-related processes, defense responses, carbohydrate and phenylpropanoid pathways was studied under various conditions (with or without pathogen and/or with or without bacterial strains) at different time-points (0-6-12-48 h). The results show that specific genes were subjected to a circadian regulation and that the expression of most of them increased in barley infected with D. teres and/or bacterized with the strain PsJN. On the contrary, a decreased gene expression was observed in the presence of strain B25. To complement and enrich the gene expression analysis, untargeted metabolomics was carried out on the same samples. The data obtained show an increase in the production of lipid compounds in barley in the presence of the pathogen. In addition, the presence of strain B25 leads to a decrease in the production of defense compounds in this crop. The results contribute to advance the knowledge on the mechanisms occurring at the onset of D. teres infection and in the presence of a biocontrol agent limiting the severity of net blotch in barley.

Background The prescription of ceftriaxone should be limited to patients with biliary tract infections and those lacking intravenous access. A specific training session for prescribers about the clinical relevance and economic value of prescribing cefotaxime instead of ceftriaxone might decrease the use of the latter in geriatric medicine. Objectives To determine the clinical and economic impact of a training session for prescribers on the subsequent prescription of third-generation cephalosporin, that is, the percentage of appropriate prescriptions and the cost of third-generation cephalosporin administration before and after the training session. Methods In a preliminary observational quasi-experimental, open-label study, appropriateness of cefotaxime and ceftriaxone prescription over a 4-week period immediately before the training session were compared with those during a 4-week period immediately afterwards. Key findings For 46 patients (29 before the training session and 17 afterwards), the proportion of cefotaxime prescriptions increased (from 3% to 35%; P = 0.007), and the proportion of appropriate prescriptions increased at the start of treatment (from 45% to 76%; P = 0.064) and at the end (from 76% to 88%; P = 0.450). The daily per-patient cost of treatment was €8 for cefotaxime and from €1.63 to €3.42 for ceftriaxone, depending on the administration route. Conclusions A training session for prescribers was associated with a decrease in ceftriaxone prescriptions encouraging further studies to improve the training session and then evaluate medico-economic impact through randomized clinical trials.

International audience; In this study, a simple method to immobilize chitosan on a poly(lactic acid) (PLA) surface was developed in a fast manner. The immobilization was realized in two steps. First, an atmospheric plasma (MWAP) torch was used to modify the PLA surface in less than 5 min in order to create enough activated sites toward the chitosan adhesion, followed by a direct dip coating to spread and immobilize chitosan on this MWAP-modified PLA surface. The modification of the PLA surface properties was confirmed by X-ray photoelectron spectroscopy (XPS), water contact angle, and atomic force microscopy. It resulted that the activated species derived from the plasma torch, i.e., hydroxyl and carboxylic acid moieties, enabled an increase of the hydrophilicity of the PLA surface. Interestingly, this activated surface allows a good spreading of chitosan solution from dip coating and leads to a homogeneous stable coating. Our XPS results bring us the hypothesis that the stabilization of the chitosan layer is mainly induced by noncovalent interactions such as hydrogen bonding and electrostatic interactions. A first insight into the biological properties of theses surfaces was assessed in terms of the antimicrobial activity of the here-designed surfaces.

International audience; Background: The relationship between myocardial work assessment using pressure-strain loops by echocardiography before cardiac resynchronization therapy (CRT) and response to CRT has been recently revealed. Among myocardial work parameters, the impact of left ventricular myocardial global wasted work (GWW) on response to CRT and outcome following CRT has been seldom studied. Hence, the authors evaluated the relationship between preprocedural GWW and outcome in a large prospective cohort of patients with heart failure (HF) and reduced ejection fraction receiving CRT. Methods: The study included 249 patients with HF. Myocardial work indices including GWW were calculated using speckle-tracking strain two-dimensional echocardiography using pressure-strain loops. End points of the study were (1) response to CRT, defined as left ventricular reverse remodeling and/or absence of hospitalization for HF, and (2) all-cause death during follow-up. Results: Median follow-up duration was 48 months (interquartile range, 43-54 months). Median preoperative GWW was 281 mm Hg% (interquartile range, 184-388 mm Hg%). Preoperative GWW was associated with CRT response (area under the curve, 0.74; P < .0001), and a 200 mm Hg% threshold discriminated CRT non responders from responders with 85% specificity and 50% sensitivity, even after adjustment for known predictors of CRT response (adjusted odds ratio, 4.03; 95% CI, 1.91-8.68; P < .001). After adjustment for established predictors of outcome in patients with HF with reduced ejection fraction receiving CRT, GWW < 200 mm Hg% remained associated with a relative increased risk for all-cause death compared with GWW >= 200 mm Hg% (adjusted hazard ratio, 2.0; 95% CI, 1.1-3.9; P = .0245). Adding GWW to a baseline model including known predictors of outcome in CRT resulted in an improvement of this model (chi(2) to improve 4.85, P = .028). The relationship between GWW and CRT response and outcome was stronger in terms of size effect and statistical significance than for other myocardial work indices. Conclusions: Low preoperative GWW (

Secondary root emergence is a crucial trait that shapes the plant’s underground system. Virtually every developmental step of root primordium morphogenesis is controlled by auxin. However, how the hormone controls cell separation in primordium-overlaying tissues through wall loosening is poorly understood. Here, we took advantage of white lupin and its spectacular cluster root development to assess the contribution of auxin to this process. We show that auxin’s positive role on rootlet emergence is associated with an upregulation of cell wall pectin modifying and degrading genes. Downregulation of a pectinolytic enzyme gene expressed in cells surrounding the primordium resulted in delayed emergence. Pectins were demethylesterified in the emergence zone and auxin treatment further enhanced this effect. Additionally, we report specific rhamnogalacturonan-I modifications during cortical cell separation. In conclusion, we propose a model in which auxin has a dual role during rootlet emergence: Firstly, through active pectin demethylesterification and secondly by regulating the expression of cell wall remodeling enzymes.

International audience; The lack of one standardized method to evaluate microplastic pollution in different aquatic environments worldwide represent a gap to fill for the scientist's community. To help overcome this challenge, we adapted an aquatic drone, named Jellyfishbot®, to sample microplastics. The aquatic drone has been compared with the actual most used method for sampling MPs in surface waters: the Manta net. In order to test the reliability of the aquatic drone in different environments, samples were collected in a river and coastal waters sites. The results obtained with the two methods were similar in term of MPs abundances, shapes and colors. It provides also a better reproducibility and more accurate sampling of MPs located in the surface waters mainly the lighter and smaller ones. This sampling method has the advantage of combining the benefits of Manta net sampling (i.e. a representative surface water sampling method that covers a large sampling area and volume (several tens m3) with those of pump filtration and grab sampling (easy access to confined and hard-to-reach areas). This new sampling method could be applied in different aquatic environments making it possible to compare the data and hence become a new standardized approach to evaluate microplastic pollution levels.

Plasmodesmata (PD) pores connect neighbouring plant cells and enable direct transport across the cell wall. Understanding the molecular composition of these structures is essential to address their formation and later dynamic regulation. Here we provide a biochemical characterisation of the cell wall co-purified with primary PD of Arabidopsis thaliana cell cultures. To achieve this result we combined subcellular fractionation, polysaccharide analyses and enzymatic fingerprinting approaches. Relative to the rest of the cell wall, specific patterns were observed in the PD fraction. Most xyloglucans, although possibly not abundant as a group, were fucosylated. Homogalacturonans displayed short methylated stretches while rhamnogalacturonan I species were remarkably abundant. Full rhamnogalacturonan II forms, highly methyl-acetylated, were also present. We additionally showed that these domains, compared to the broad wall, are less affected by wall modifying activities during a time interval of days. Overall, the protocol and the data presented here open new opportunities for the study of wall polysaccharides associated with PD.

International audience; To investigate the microbial community in the marine environment by molecular approaches, it is important to extract DNA in sufficient quantity and purity. The presence of inhibitors in the samples can lead to false negative results or a loss of information, but can be highlighted by a process control in the experiments. We compared seven bacterial DNA extraction methods on marine samples: fish skin, gills and guts, mollusk meat, phytoplankton and zooplankton. A process control (Listeria monocytogenes) was added in half of the samples. The performance of the DNA extraction methods were compared to produce the more pure and concentrated DNA for qPCR amplification targeting the bacterial tuf gene and the process control hlyA gene. The purity and concentration of DNA were determined by spectrophotometry assays. The results showed that the highest purity and concentration of DNA were obtained using the PowerBiofilm and PureLink Microbiome kits. The qPCR data confirmed these kits produced better bacterial DNA purity and concentration with higher amplification efficiency. In some samples, the presence of inhibitors was detected by qPCR targeting the hlyA gene, showing that the samples were heterogeneous contaminated with inhibitors. The DNA extracts are suitable for genetic downstream applications in the marine environment.

International audience; Kinesiophobia is associated with pain intensity in people suffering from chronic pain. The number of publications highlighting this relationship has increased significantly in recent years, emphasizing the importance of investigating and synthesizing research evidence on this topic. The purpose of this scoping review was to answer the following questions: (1) What types of interventions have been or are currently being studied in randomized controlled trials (RCTs) for the management of kinesiophobia in patients with chronic pain? (2) What chronic pain conditions are targeted by these interventions? (3) What assessment tools for kinesiophobia are used in these interventions? According to the studies reviewed, (1) physical exercise is the most commonly used approach for managing irrational fear of movement, (2) interventions for kinesiophobia have primarily focused on musculoskeletal pain conditions, particularly low back pain and neck pain, and (3) the Tampa Scale of Kinesiophobia is the most commonly used tool for measuring kinesiophobia. Future RCTs should consider multidisciplinary interventions that can help patients confront their irrational fear of movement while taking into account the patient's personal biological, psychological, and social experiences with pain and kinesiophobia.

International audience; To power the specific recognition and binding of protein partners into functional complexes, a wealth of information about the structure and function of the partners is necessarily encoded into the global shape of protein-protein interfaces and their local topological features. To identify whether this is the case, this study uses convolutional deep learning methods (typically leveraged for 2D image recognition) on 3D voxel representations of protein-protein interfaces colored by burial depth. A novel twostage network, fed with voxelizations of each interface at two distinct resolutions, achieves balance between performance and computational cost. From the shape of the interfaces, the network tries to predict the presence of secondary structure motifs at the interface and the molecular function of the corresponding complex. Secondary structure and certain classes of function are found to be very well predicted, validating the hypothesis of interface shape as a conveyor of higher-level information. Interface patterns triggering the recognition of specific classes are also identified and described.

Corresponding authors:21 Jérôme Pelloux (jerome.pelloux@u-picardie.fr)22 Davide Mercadante (davide.mercadante@auckland.ac.nz)23 Fabien Sénéchal (fabien.senechal@u-picardie.fr); The fine-tuning of pectins by polygalacturonases (PGs) plays a key role in modulating plant cell wall chemistry and mechanics, impacting plant development. The high number of plant PG isoforms and their absence of inhibition by endogenous PG-Inhibiting Proteins (PGIPs) question the regulation of pectin depolymerization during development. Our understanding of the diversity and of the regulation of plant PGs has been impaired by the lack of protein structures. Here we resolved the crystal structures of two PGs from Arabidopsis, PGLR and ADPG2, whose expression overlap in roots and determined why plant PGs are not inhibited by PGIPs. By combining molecular dynamic simulations, analysis of enzymes’ kinetics and hydrolysis products, we showed that subtle differences in PGLR and ADPG2 structures translated into distinct dynamics and processivities. This leads to peculiar effects on root development, as determined by exogenous applications of enzymes.

IntroductionChronic obstructive pulmonary disease (COPD) is a leading cause of mortality in Europe; however, it is important to understand how clinical practice patterns differ between countries and how this might relate to disease outcomes, to identify ways of improving local disease management. We aimed to describe and compare the management of patients with COPD in the UK and France between 2008 and 2017.MethodsWe used data from the Clinical Practice Research Datalink GOLD and Hospital Episode Statistics in the UK and the Echantillon Généraliste des Bénéficiaire in France to identify patients with COPD each year between 2008 and 2017. We compared patient characteristics, all-cause mortality and COPD exacerbations each year between 2008 and 2017 for patients in the UK and France separately. Health care utilisation and COPD exacerbations in 2017 were compared between France and the UK using t-tests and χ2tests.ResultsPatients with COPD were similar in gender and comorbidities in both countries. Incidence of COPD exacerbations remained stable in the UK and France between 2007 and 2017. In 2017, the proportion of all-cause and COPD-related hospitalisations was greater in the UK than in France (43.9% vs 32.8% and 8.3% vs 4.9%, respectively; pDiscussionOverall, UK patients were more likely to go to A&E, be hospitalised for COPD-related causes and stay in hospital for fewer days after being admitted for COPD-related reasons compared with patients in France, illustrating a difference in health-seeking behaviours and access to healthcare.

International audience; Genome-wide association studies unveiled the associations between the single nucleotide polymorphism rs16969968 of CHRNA5, encoding the nicotinic acetylcholine receptor alpha5 subunit (α5SNP), and nicotine addiction, cancer, and COPD independently. Here, we investigated α5SNP-induced epithelial remodeling and inflammatory response in human COPD airways. We included 26 α5SNP COPD patients and 18 wild-type α5 COPD patients in a multi-modal study. A comparative histologic analysis was performed on formalin-fixed paraffin-embedded lung tissues. Isolated airway epithelial cells from bronchial brushings were cultivated in the air-liquid interface. Broncho-alveolar fluids were collected to detect inflammatory mediators. Ciliogenesis was altered in α5SNP COPD bronchial and bronchiolar epithelia. Goblet cell hyperplasia was exacerbated in α5SNP small airways. The broncho-alveolar fluids of α5SNP COPD patients exhibited an increase in inflammatory mediators. The involvement of the rs16969968 polymorphism in airway epithelial remodeling and related inflammatory response in COPD prompts the development of innovative personalized diagnostic and therapeutic strategies.

International audience; The French National Reference Center for Invasive Mycoses and Antifungals leads an active and sustained nationwide surveillance program on probable and proven invasive fungal diseases (IFDs) to determine their epidemiology in France. Between 2012 and 2018, a total of 10,886 IFDs were recorded. The incidence increased slightly over time (2.16 to 2.36/10,000 hospitalization days, P = 0.0562) in relation with an increase of fungemia incidence (1.03 to 1.19/10,000, P = 0.0023), while that of other IFDs remained stable. The proportion of ≥65-year-old patients increased from 38.4% to 45.3% (P < 0.0001). Yeast fungemia (n = 5,444) was due mainly to Candida albicans (55.6%) with stable proportions of species over time. Echinocandins became the main drug prescribed (46.7% to 61.8%), but global mortality rate remained unchanged (36.3% at 1 month). Pneumocystis jirovecii pneumonia (n = 2,106) was diagnosed mostly in HIV-negative patients (80.7%) with a significantly higher mortality than in HIV-positive patients (21.9% versus 5.4% at 1 month, P < 0.0001). Invasive aspergillosis (n = 1,661) and mucormycosis (n = 314) were diagnosed mostly in hematology (>60% of the cases) with a global mortality rate of 42.5% and 59.3%, respectively, at 3 months and significant changes in diagnosis procedure over time. More concurrent infections were also diagnosed over time (from 5.4% to 9.4% for mold IFDs, P = 0.0115). In conclusion, we observed an aging of patients with IFD with a significant increase in incidence only for yeast fungemia, a trend toward more concurrent infections, which raises diagnostic and therapeutic issues. Overall, global survival associated with IFDs has not improved despite updated guidelines and new diagnostic tools.IMPORTANCE The epidemiology of invasive fungal diseases (IFDs) is hard to delineate given the difficulties in ascertaining the diagnosis that is often based on the confrontation of clinical and microbiological criteria. The present report underlines the interest of active surveillance involving mycologists and clinicians to describe the global incidence and that of the main IFDs. Globally, although the incidence of Pneumocystis pneumonia, invasive aspergillosis, and mucormycosis remained stable over the study period (2012 to 2018), that of yeast fungemia increased slightly. We also show here that IFDs seem to affect older people more frequently. The most worrisome observation is the lack of improvement in the global survival rate associated with IFDs despite the increasing use of more sensitive diagnostic tools, the availability of new antifungal drugs very active in clinical trials, and a still low/marginal rate of acquired in vitro resistance in France. Therefore, other tracks of improvement should be investigated actively.

International audience; Les additifs plastiques, ajoutés aux polymères au cours de leur formulation, participent aux dangers que posent l’utilisation et le rejet de plastique dans l’environnement. Cet impact dit « chimique » a été démontré à de multiples reprises. En effet, une fois dans l’environnement, les additifs plastiques peuvent être libérés de la matrice polymérique et diffuser dans l’eau environnante ou au sein des organismes après ingestion de particules de plastiques. L’utilisation de certains additifs est controversée car ils se sont révélés être toxiques pour l’environnement, les organismes marins et l’Homme. Afin d’avoir une meilleure compréhension de l’impact chimique de ces additifs, il est important de les identifier, et idéalement de les quantifier. Après avoir sélectionné une soixantaine de ces additifs (plastifiants, retardateurs de flammes, antioxydants, …), une méthode unique pour l’analyse de l'ensemble ces molécules a été développée en pyrolyse couplée à la chromatographie gazeuse et la spectrométrie de masse haute résolution (Py-GC-HRMS). La méthode développée à ensuite permis d’identifier la présence de divers additifs plastiques dans des échantillons de barquettes plastiques alimentaires en polypropylène (PP) et en acide polylactique (PLA). Au vu des additifs mis en évidence dans ces échantillons, et du fait de la forte présence de barquettes alimentaires dans l’environnement, une étude complémentaire s’est portée sur l’impact potentiel de ces additifs sur les stades de reproduction et les jeunes stades de vies de l’huitre creuse (Crassostrea gigas) (une espèce sentinelle, ingénieure et mondialement commercialisée), après exposition à des lixiviats de ces échantillons.

International audience; Acute lymphoblastic leukemias (ALL) are characterized by a large number of cytogenetic abnormalities of clinical interest that require the use of several complementary techniques. Optical genome mapping (OGM) is based on analysis of ultra-high molecular weight DNA molecules that provides a high-resolution genome-wide analysis highlighting copy number and structural anomalies, including balanced translocations. We compared OGM to standard techniques (karyotyping, fluorescent in situ hybridization, single nucleotide polymorphism-array and reverse transcription multiplex ligation-dependent probe amplification) in 10 selected B or T-ALL. Eighty abnormalities were found using standard techniques of which 72 (90%) were correctly detected using OGM. Eight discrepancies were identified, while 12 additional anomalies were found by OGM. Among the discrepancies, four were detected in raw data but not retained because of filtering issues. However, four were truly missed, either because of a low variant allele frequency or because of a low coverage of some regions. Of the additional anomalies revealed by OGM, seven were confirmed by another technique, some of which are recurrent in ALL such as LMO2-TRA and MYC-TRB fusions. Despite false positive anomalies due to background noise and a case of inter-sample contamination secondarily identified, the OGM technology was relatively simple to use with little practice. Thus, OGM represents a promising alternative to cytogenetic techniques currently performed for ALL characterization. It enables a time and cost effective analysis allowing identification of complex cytogenetic events, including those currently inaccessible to standard techniques.

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Contains fulltext : 234032.pdf (Publisher’s version ) (Closed access) Recurrence of primary membranous nephropathy after transplantation occurs in up to 44% of patients and is driven by PLA2R antibody. Here, we asked whether genetic determinants could improve risk prediction. First, we sequenced PLA2R1 and HLA-D loci in 248 patients with primary membranous nephropathy and identified two independent single nucleotide polymorphisms (SNPs) at risk for primary membranous nephropathy at each locus. These were rs9271188 (intergenic between HLA-DRB1 and HLA-DQA1,) and rs9275086 (intergenic between HLA-DQB1 and HLA-DQA2) at the HLA-D locus along with rs6726925 and rs13018963 at the PLA2R1 locus. Then we investigated whether primary membranous nephropathy at-risk variants were associated with recurrence in a retrospective cohort of 105 donor-recipient pairs and a replication cohort of 40 pairs. Seven SNPs located between HLA-DRB1 and HLA-DQA1 in linkage disequilibrium with rs9271188, and three SNPs in the PLA2R1 region predicted recurrence when presented by the donor, but not when presented by the recipient. The two SNPs in the HLA-D region most strongly associated with recurrence (rs9271705 and rs9271550) were confirmed in the replication cohort. A genetic risk score based on the two best predictors at each locus (rs9271705, rs9271550, rs17830558, and rs3828323) identified a group of patients with high risk of recurrence. Thus, our results suggest that the graft contributes to recurrence of primary membranous nephropathy through the disease susceptibility HLA-D and PLA2R1 SNPs in an autoimmune milieu. Further studies are needed before implementation of genetic testing for these in donor selection.

International audience; Fusarium oxysporum is the one of the most common and impactful pathogens of flax. Cultivars of flax that show resistance to this pathogen have previously been identified. To better understand the mechanisms that are responsible for this resistance, we conducted time-lapse analysis of one susceptible and one resistant cultivar over a two-week period following infection. We also monitored changes in some metabolites. The susceptible cultivar showed a strong onset of symptoms from 6 to 8 days after inoculation, which at this time point, was associated with changes in metabolites in both cultivars. The resistant cultivar maintained its height and normal photosynthetic capacity but showed a reduced growth of its secondary stems. This resistance was correlated with the containment of the pathogen at the root level, and an increase in some metabolites related to the phenylpropanoid pathway.

International audience; There is no comprehensive method for differentiating between fresh and frozen-thawed fish fillets. This is an ongoing problem, particularly in relation to regulations. In this study, we showed the relevance of using the properties of mitochondria to discriminate fresh fish fillets from frozen-thawed fish fillets. The use of red muscle fibres of Gilthead sea bream allowed us to leave mitochondria in their physiological environment and to avoid possible alterations of mitochondrial membranes during isolation steps. The impact of freezing on fillets was evaluated by measuring the permeability of fibres and mitochondrial membranes to nicotinamide adenine dinucleotide + hydrogen (NADH). NADH permeability of fresh fillet fibres stored at 4°C was compared to the permeability of fibres extracted from frozen-thawed fillets. Two approaches were used to measure permeability changes: a spectrophotometric method that measured consumption of NADH by complex I, and an oxygraphic approach that measured stimulation of O 2 consumption by NADH. Fibres from frozen-thawed fillets were more permeable to NADH and were less sensitive to the permeabilizer alamethicin. The 2 sensitivity of this method allowed us to clearly detect red muscle fibres from frozen-thawed fish versus fresh fish fillets.

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International audience; Background: Most cases of left-sided native valve infective endocarditis (IE) involve a single valve and little is known concerning IE that simultaneously affects the aortic and mitral valves. Methods: We aimed to determine the characteristics, identify the prognostic factors, and define the effect of early surgery for patients with left-sided native bivalvular IE. This analysis included 1340 consecutive patients who presented with definite acute left-sided native valve IE in a 2-centre cohort study. Results: A bivalvular involvement was present in 257 patients (19%). Patients with bivalvular IE had more embolic events (P = 0.044), congestive heart failure (P = 0.016), vegetations, and perivalvular complications (both P < 0.001) than those with monovalvular IE. Early surgery was more frequent for patients with bivalvular IE (P < 0.001). Thirty-day mortality was higher for patients with bivalvular IE than for those with monovalvular IE (24.5% vs 17.6%; P = 0.008), even after adjustment (odds ratio, 1.86 [95% confidence interval, 1.26-2.73]; P < 0.001). Estimated 10-year survival was 70% +/- 1% for monovalvular IE and 59% +/- 3% for bivalvular IE (P = 0.002). Bivalvular IE was still associated with mortality in multivariable Cox analysis, after adjustment for covariates including age, neurological events, congestive heart failure, Staphylococcus spp infection, perivalvular complications, and early surgery (hazard ratio, 1.70 [95% confidence interval, 1.31-2.11]; P < 0.001). Early surgery was associated with increased survival for patients with bivalvular IE (79% +/- 4% vs 35% +/- 6%; P < 0.001). Conclusions: Bivalvular involvement is frequent in left-sided native valve IE, is associated with more embolic events and congestive heart failure than monovalvular IE, and patients are at a high risk of death. Early surgery is associated with improved survival and should be systematically discussed in the absence of contraindication.

Rhamnolipids are a specific class of microbial surfactants, which hold great biotechnological and therapeutic potential. However, their exploitation at the industrial level is hampered because they are mainly produced by the opportunistic pathogen Pseudomonas aeruginosa. The non-human pathogenic bacterium Pantoea ananatis is an alternative producer of rhamnolipid-like metabolites containing glucose instead of rhamnose residues. Herein, we present the isolation, structural characterization, and total synthesis of ananatoside A, a 15-membered macrodilactone-containing glucolipid, and ananatoside B, its open-chain congener, from organic extracts of P. ananatis. Ananatoside A was synthesized through three alternative pathways involving either an intramolecular glycosylation, a chemical macrolactonization or a direct enzymatic transformation from ananatoside B. A series of diasteroisomerically pure (1→2), (1→3), and (1→4)-macrolactonized rhamnolipids were also synthesized through intramolecular glycosylation and their anomeric configurations as well as ring conformations were solved using molecular modeling in tandem with NMR studies. We show that ananatoside B is a more potent surfactant than its macrolide counterpart. We present evidence that macrolactonization of rhamnolipids enhances their cytotoxic and hemolytic potential, pointing towards a mechanism involving the formation of pores into the lipidic cell membrane. Lastly, we demonstrate that ananatoside A and ananatoside B as well as synthetic macrolactonized rhamnolipids can be perceived by the plant immune system, and that this sensing is more pronounced for a macrolide featuring a rhamnose moiety in its native 1C4 conformation. Altogether our results suggest that macrolactonization of glycolipids can dramatically interfere with their surfactant properties and biological activity., We show that macrolactonization of gluco- and rhamnolipids dramatically interfere with their surfactant properties and biological activity.

International audience; Bacteria within biofilms may be exposed to sub-minimum inhibitory concentrations (sub-MICs) of antibiotics. Cell-to-cell contact within biofilms facilitates horizontal gene transfers and favors induction of the SOS response. Altogether, it participates in the emergence of antibiotic resistance. Aminoglycosides at sub-MICs can induce the SOS response through NO accumulation in E. coli carrying the small plasmid with the quinolone resistance qnrD gene (pDIJ09-518a). In this study, we show that in E. coli pDIJ09-518a, the SOS response triggered by sub-MICs of aminoglycosides has important consequences, promoting genetic rearrangement in class 1 integrons and biofilm formation. We found that the integrase expression was increased in E. coli carrying pDIJ09-518a in the presence of tobramycin, which was not observed for the WT isogenic strain that did not carry the qnrD-plasmid. Moreover, we showed that biofilm production was significantly increased in E. coli WT/pDIJ09-518a compared to the WT strain. However, such a higher production was decreased when the Hmp-NO detoxification pathway was fully functional by overexpressing Hmp. Our results showing that a qnrD-plasmid can promote biofilm formation in E. coli and potentiate the acquisition and spread of resistance determinants for other antibiotics complicate the attempts to counteract antibiotic resistance and prevention of biofilm development even further. We anticipate that our findings emphasize the complex challenges that will impact the decisions about antibiotic stewardship, and other decisions related to retaining antibiotics as effective drugs and the development of new drugs.

Reproducibility in organ size and shape is a fundamental trait of living organisms. The mechanisms underlying such robustness remain, however, to be elucidated. Taking the sepal of Arabidopsis as a model, we investigated whether variability of gene expression plays a role in variation of organ morphology. To address this question, we produced a dataset composed of both transcriptomic and morphological information obtained from 27 individual sepals from wild-type plants. Although nearly identical in their genetic background, environment, and developmental stage, these sepals exhibited appreciable variability in both morphology and transcriptome. We identified modules of co-expressed genes in sepals, three of which correlated significantly with morphology, revealing biologically relevant gene regulatory networks. Interestingly, cell-wall related genes were overrepresented in two of these three modules. Additionally, we found that highly variable genes were unexpectedly enriched in cell-wall related processes. We then analyzed sepal morphology from 16 cell-wall mutants and found that the more a gene is expressed in wild-type, the more variable the morphology of the corresponding mutant. Altogether, our work unravels the contribution of cell-wall related genes to the robustness of sepal morphology. More generally, we propose that canalizing traits during development could rely on the modulation of highly expressed genes.

International audience; The marine environment is a potential natural reservoir of antimicrobial resistance genes (ARGs), subject to anthropogenic effluents (wastewater, industrial, and domestic), and known as a final receiving system. The aim of this study was to investigate the abundance and geographical distribution of the three bla TEM , sul1 , and intI1 genes, proposed as indicators of contamination to assess the state of antimicrobial resistance in environmental settings, added to the tetA gene and the microbial population ( tuf gene) in the English Channel and North Sea areas. Bacterial DNA was extracted from 36 seawater samples. The abundance of these genes was determined by quantitative PCR (qPCR) and was analyzed in association with environmental variables and geographical locations to determine potential correlations. The bla TEM and tetA genes were quantified in 0% and 2.8% of samples, respectively. The sul1 and intI1 genes were detected in 42% and 31% of samples, respectively, with an apparent co-occurrence in 19% of the samples confirmed by a correlation analysis. The absolute abundance of these genes was correlated with the microbial population, with results similar to the relative abundance. We showed that the sul1 and intI1 genes were positively correlated with dissolved oxygen and turbidity, while the microbial population was correlated with pH, temperature and salinity in addition to dissolved oxygen and turbidity. The three tetA , sul1 , and intI1 genes were quantified in the same sample with high abundances, and this sample was collected in the West Netherlands coast (WN) area. For the first time, we have shown the impact of anthropogenic inputs (rivers, man-made offshore structures, and maritime activities) and environmental variables on the occurrence of three indicators of environmental contamination by antimicrobial resistance in the North Sea and English Channel seawaters.

International audience; No abstract available

International audience; No data concerning antiretroviral drug's (ARV) primary resistance mutation rates in Chad are available. We retrospectively analysed frozen-stored dried blood spot samples that were collected from 48 Chadian human immunodeficiency virus (HIV)-1 seropositive patients naïve of ARV. HIV-1 protease and reverse transcriptase genes were successfully sequenced for 24 (60.0%) of the 40 patients displaying a viral load > 1000 copies/ml. Seven (29.2%) displayed mutations conferring resistance against one or more classes of ARV. We evidenced high levels of primary ARV resistance mutations in Chad, but lower than those observed in patients with failure to first-line ARV.

International audience; Esca is a complex grapevine trunk disease caused by wood-rotting ascomycetes and basidiomycetes and leading to several foliar and wood symptoms. Given that the esca expression can be influenced by several environmental, physiological, and genetic factors, foliar symptoms are inconsistent in incidence and prevalence and may appear 1 year but not the following. We have previously reported a clone-dependent expression of the disease in cv Chardonnay. Owing to metabolome analysis, we could discriminate the metabolite fingerprint of green leaves collected on diseased vines of clones 76 and 95. These clone-dependent fingerprints were year-dependent in intensity and nature. The present work was conducted to determine if the clone-dependent disease expression observed is specific to Chardonnay or if it also occurs in another cultivar. A plot located in the Jura vineyard (France) and planted with both 1004 and 1026 clones of Trousseau, a cultivar highly susceptible to esca, was thus selected and studied during 2017 and 2018. A year-dependent variation of the symptoms expression was first observed and a possible relationship with rainfall is hypothesized and discussed. Moreover, a higher percentage of the clone 1026 vines expressed disease, compared to the 1004 ones, suggesting the higher susceptibility of this clone. Finally, metabolomic analyses of the remaining green leaves (i.e, without symptom expression) of partial esca-apoplectic vines allowed us to confirm a clone-dependent metabolic response to the disease. The metabolite fingerprints obtained differed in nature and intensity to those previously reported for Chardonnay and also between years.

Overexpression of EGFR drives glioblastomas (GBM) cell invasion but these tumours remain resistant to EGFR-targeted therapies such as tyrosine kinase inhibitors (TKIs). Endocytosis, an important modulator of EGFR function, is often dysregulated in glioma cells and is associated with therapy resistance. However, the impact of TKIs on EGFR endocytosis has never been examined in GBM cells. In the present study, we showed that gefitinib and other tyrosine kinase inhibitors induced EGFR accumulation in early-endosomes as a result of an increased endocytosis. Moreover, TKIs trigger early-endosome re-localization of another membrane receptor, the fibronectin receptor alpha5beta1 integrin, a promising therapeutic target in GBM that regulates physiological EGFR endocytosis and recycling in cancer cells. Super-resolution dSTORM imaging showed a close-proximity between beta1 integrin and EGFR in intracellular membrane compartments of gefitinib-treated cells, suggesting their potential interaction. Interestingly, integrin depletion delayed gefitinib-mediated EGFR endocytosis. Co-endocytosis of EGFR and alpha5beta1 integrin may alter glioma cell response to gefitinib. Using an in vitro model of glioma cell dissemination from spheroid, we showed that alpha5 integrin-depleted cells were more sensitive to TKIs than alpha5-expressing cells. This work provides evidence for the first time that EGFR TKIs can trigger massive EGFR and alpha5beta1 integrin co-endocytosis, which may modulate glioma cell invasiveness under therapeutic treatment.

Despite the pivotal role of jasmonic acid in the outcome of plant-microorganism interactions, JA-signaling components in roots of perennial trees like western balsam poplar (Populus trichocarpa) are poorly characterized. Here we decipher the poplar-root JA-perception complex centered on PtJAZ6, a co-repressor of JA-signaling targeted by the effector protein MiSSP7 from the ectomycorrhizal basidiomycete Laccaria bicolor during symbiotic development. Through protein–protein interaction studies in yeast we determined the poplar root proteins interacting with PtJAZ6. Moreover, we assessed via yeast triple-hybrid how the mutualistic effector MiSSP7 reshapes the association between PtJAZ6 and its partner proteins. In the absence of the symbiotic effector, PtJAZ6 interacts with the transcription factors PtMYC2s and PtJAM1.1. In addition, PtJAZ6 interacts with it-self and with other Populus JAZ proteins. Finally, MiSSP7 strengthens the binding of PtJAZ6 to PtMYC2.1 and antagonizes PtJAZ6 homo-/heterodimerization. We conclude that a symbiotic effector secreted by a mutualistic fungus may promote the symbiotic interaction through altered dynamics of a JA-signaling-associated protein–protein interaction network, maintaining the repression of PtMYC2.1-regulated genes.