Identification of putative interactors of arabidopsis sugar transporters

Identification of Putative Interactors of Arabidopsis Sugar Transporters

International audience; Hexoses and disaccharides are the key carbon sources for essentially all physiological processes across kingdoms. In plants, sucrose, and in some cases raffinose and stachyose, are transported from the site of synthesis in leaves, the sources, to all other organs that depend on import, the sinks. Sugars also play key roles in interactions with beneficial and pathogenic microbes. Sugar transport is mediated by transport proteins that fall into super-families. Sugar transporter (ST) activity is tuned at different levels, including transcriptional and posttranslational levels. Understanding the ST interactome has a great potential to uncover important players in biologi…

Additional file 1 of Experimental community coalescence sheds light on microbial interactions in soil and restores impaired functions

Additional file 1: Supplementary Table 1. Number of OTUs significantly differentially abundant among all treatments as estimated using a generalized linear mixed model, among the 515 most abundant 16S rRNA OTUs and the 439 most abundant 18S rRNA OTUs. Supplementary Figure 1. Abundances of total bacteria and total fungi. Quantification of 16S rRNA (a and c) and ITS (b and d) gene copy numbers in the original soil, the removal treatments and the control (Step 1; a and b) and in the coalescence treatment, the self-mixed removal treatment and the control samples (Step 2; c and d) (mean ± s.e. of log10-transformed data expressed as gene copy g-1 dry soil). Letters indicate significantly differen…

Deciphering biotic interactions and their role in soil microbial community assembly

National audience; Soil microbial communities play key roles in ecosystem functioning. Yet, little is known aboutthe importance of microbe-microbe interactions in soil microbial community assembly andfunctions. To address this knowledge gap, the objective of my thesis is to assess the role ofinteractions between micro-organisms in soil microbial communities. For this purpose, we willmanipulate the interactions between microorganisms within complex soil microbialcommunities by (i) removing different members of the soil community, (ii) adding microbialtaxa to the soil community and (iii) increasing the physical distance between members of thesoil community. How shifts in microbial interaction…

Unraveling biotic interactions determining soil microbial community assembly and functioning

National audience; Microbial communities are at the heart of all ecosystems and yet, a sound understanding of the ecological processes governing the assembly of these communities in the environment is missing. To address the role of biotic interactions in assembly and functioning of the soil microbiota, we used a top down manipulation approach based on the removal of various populations in a natural microbial community. Suspensions of the soil microbiota were subjected to various biocidal and filtration treatments before being inoculated into the same sterilized soil. We hypothesized that if biotic interactions are an important shaping force of the microbiota assembly, removal of microbial …

The membrane proteome of Medicago truncatula roots displays qualitative and quantitative changes in response to arbuscular mycorrhizal symbiosis

International audience; Arbuscular mycorrhizal (AM) symbiosis that associates roots of most land plants with soil-borne fungi (Glomeromycota), is characterized by reciprocal nutritional benefits. Fungal colonization of plant roots induces massive changes in cortical cells where the fungus differentiates an arbuscule, which drives proliferation of the plasma membrane. Despite the recognized importance of membrane proteins in sustaining AM symbiosis, the root microsomal proteome elicited upon mycorrhiza still remains to be explored. In this study, we first examined the qualitative composition of the root membrane proteome of Medicago truncatula after microsome enrichment and subsequent in dep…

Antibiotrophie : une fonction émergente favorisant l’implantation des bactéries antibiorésistantes dans les sols

National audience; La fonction antibiotrophique, permettant l’utilisation d’antibiotiques comme source nutritive, arécemment été découverte chez des bactéries antibiorésistantes environnementales. Pourvérifier si leur avantage sélectif en environnements pollués s’en trouvait augmenté, nous avonsconduit une expérience en microcosmes dans laquelle Microbacterium sp. C448 (C448),présentant des capacités de résistance et de dégradation vis-à-vis des sulfamides, a été inoculéedans quatre sols supplémentés ou non par l’antibiotique sulfaméthazine (SMZ) et/ou du lisier.Après un mois d’incubation, C448 n’a été détectée que dans les sols traités avec la SMZ,indiquant une faible compétitivité de la s…

Antibiotrophy: Key Function for Antibiotic-Resistant Bacteria to Colonize Soils—Case of Sulfamethazine-Degrading Microbacterium sp. C448

Chronic and repeated exposure of environmental bacterial communities to anthropogenic antibiotics have recently driven some antibiotic-resistant bacteria to acquire catabolic functions, enabling them to use antibiotics as nutritive sources (antibiotrophy). Antibiotrophy might confer a selective advantage facilitating the implantation and dispersion of antibiotrophs in contaminated environments. A microcosm experiment was conducted to test this hypothesis in an agroecosystem context. The sulfonamide-degrading and resistant bacterium Microbacterium sp. C448 was inoculated in four different soil types with and without added sulfamethazine and/or swine manure. After 1 month of incubation, Micro…

Bacterial hppd: a biomarker of exposure of soils to beta-triketone herbicides?

National audience; β-triketone herbicides are among the most used herbicides in corn crop to control broadleaf weeds.These herbicides inhibit the 4-hydroxyphenylpyruvate dioxygenase (4-HPPD) and lead to bleaching anddeath of weeds. This enzyme is not only found in plants but in all living organisms, includingmicroorganisms where it takes part to the tyrosine degradation pathway. Thus, microorganismsclassified as “non-target organisms” by current EU regulation for pesticide authorization, might beimpacted by β-triketones, with possible domino effect on microbial functions supporting soilecosystem services (Thiour-Mauprivez et al. 2019). Since microorganisms have been proposed by EFSAas key-d…

Répercussions spatiales de l’esca sur l’holobionte vigne : réponse du microbiome dans le continuum sol/feuilles

Dans le cadre du projet Holoviti (Plan National Dépérissement du Vignoble), l’holobionte vigne est étudié, dans le continuum sol - racines - parties aériennes (SRP), chez des ceps symptomatiques (S) ou asymptomatiques (AS) de la forme lente d’esca (tigrures foliaires). Ces recherches ont été réalisées sur une parcelle du château de Marsannay, située sur la commune de Couchey en Côte d’Or (21). Celle-ci a été choisie car elle présente simultanément trois types de dépérissements : deux liés à des agents pathogènes, respectivement viraux (agent du court-noué) et fongiques (agents de l’esca), et un lié à des dysfonctionnements physiologiques (porte-greffe 161-49C). Cette parcelle a été cartogra…

The evolution of nitric oxide signalling diverges between the animal and the green lineages

AbstractNitric oxide (NO) is a ubiquitous signalling molecule with widespread distribution in prokaryotes and eukaryotes where it is involved in countless physiological processes. While the mechanisms governing nitric oxide (NO) synthesis and signalling are well established in animals, the situation is less clear in the green lineage. Recent investigations have shown that NO synthase, the major enzymatic source for NO in animals, is absent in land plants but present in a limited number of algae. The first detailed analysis highlighted that these new NO synthases are functional but display specific structural features and probably original catalytic activities. Completing this picture, analy…

Experimental community coalescence sheds light on microbial interactions in soil and restores impaired functions

Abstract Background Microbes typically live in communities where individuals can interact with each other in numerous ways. However, knowledge on the importance of these interactions is limited and derives mainly from studies using a limited number of species grown in coculture. Here, we manipulated soil microbial communities to assess the contribution of interactions between microorganisms for assembly of the soil microbiome. Results By combining experimental removal (taxa depletion in the community) and coalescence (mixing of manipulated and control communities) approaches, we demonstrated that interactions between microorganisms can play a key role in determining their fitness during soi…

Nitric oxide synthase in plants: Where do we stand?

International audience

Evidence of a core microbiota shaped by plant and earthworm interactions across soils

Prod 2018-139a EA AGROSUP INRA BIOME IPM; International audience; While having distinct niches, plants and earthworms have occupied soils over geological times, mutually influencing each-others. These macroorganisms are considered “ecosystem engineers”, actively modifying soil physical structure, which notably provides specific habitats for microorganisms: the rhizosphere and the drilosphere (casts/burrows produced by earthworms). In this study, we aimed to disentangle the relative importance of both macroorganisms in shaping microbial community assembly in different soil types, and determine the extent and modalities of how rhizosphere and drilosphere communities may coalesce with each-oth…

Nitric oxide production and signalling in algae

International audience

A core microbiota of plant and earthworm interaction? Phylogenetic and functional aspects

International audience; The core microbiota concept has been proposed to describe the subset of a microbiota (e.g. the rhizosphere microbial community) associated with a given host (e.g. a plant) going beyond macroenvironment differences (e.g. soil type), and characterized by taxonomic markers (e.g. 16S rRNA gene sequences). Its existence has been questioned by geographical studies, showing the overruling soil type effect in shaping microbial communities. As far as biotic determinants are concerned, several “hosts” or macroorganisms are impacting a given habitat and its specific microbial community. In soils, there is an overlap between the so-called rhizosphere and the drilosphere, defined…

Production et signalisation dépendante du monoxyde d'azote dans la lignée verte la surprise des microalgues

National audience