Project description:This study evaluates the transcriptome of Arabidopsis thaliana seedlings growing in the presence of a 35-member bacterial SynCom under different phosphate availability
Project description:This study evaluates the transcriptome of Arabidopsis thaliana seedlings growing in the presence of a 185-member bacterial SynCom under different phosphate availability
Project description:Anthropogenic perturbations to the nitrogen cycle, primarily through use of synthetic fertilizers, have caused unprecedented increases in the emission of nitrous oxide (N2O) in recent decades. As a potent greenhouse gas, and an ozone depleting substance, understanding the sources and sinks of N2O is of vital importance. Nitrate (NO3-) reducing microbes are a primary contributor to the biotic production of N2O in anoxic regions of soil, marine systems, and wastewater treatment facilities through the process of denitrification. Thus, developing a better understanding of denitrifying microbial communities, and the environmental factors that influence N2O emissions may provide strategies to mitigate emissions in agriculture and wastewater treatment. Here, through comprehensive genome analysis, we show that pathway partitioning is a common strategy utilized by microbial communities to perform complete denitrification. Through detailed physiological characterization and kinetic modeling of a cooperative synthetic community (SynCom) assembled by pairing bacterial isolates from a field site heavily contaminated with NO3-, we also provide insight into the controls of N2O emissions. We demonstrate that members of this SynCom cooperate to perform complete denitrification through exchange of nitrite (NO2-) and nitric oxide (NO), and that community context drives global physiological changes in each member. We identify links between amino acid metabolism and denitrification activity as well as indicators of competition and amino acid exchange. We also show that NO2- toxicity with unbalanced growth of community members drives N2O production, suggesting that this SynCom provides a simplified, environmentally relevant, model of pathway partitioning in denitrifying communities. This SynCom should provide a framework with which to further explore how environmental context can impact cooperation and lead to the production of N2O
Project description:This study evaluates the transcriptome of Arabidopsis thaliana roots exposed to the MAMP flg22 in the presence of a 35-member bacterial SynCom
Project description:<p>Background</p><p>Wheat crown rot (WCR) caused by Fusarium spp. lacks durable, sustainable control. Engineering the rhizosphere with defined synthetic microbial communities (SynComs) offers a route to combined disease suppression and growth promotion. We aimed to build a cross-kingdom SynCom and evaluate its impacts on plant performance and the soil–microbiome system.</p><p>Results</p><p>We assembled a two-member SynCom comprising an antagonistic fungus (Trichoderma harzianum) and a growth-promoting bacterium (Bacillus rugosus). In greenhouse trials, SynCom inoculation reduced WCR severity by ~71% and improved vigor, more than doubling shoot and root biomass and increasing grain weight by ~13% versus non-inoculated controls. SynCom-treated plants maintained higher chlorophyll and antioxidant enzyme activities under pathogen challenge, with reduced oxidative stress markers relative to pathogen-only plants. Amplicon sequencing showed increased rhizosphere microbial diversity, enrichment of beneficial taxa (e.g., Mortierella), and suppression of Fusarium. SynCom also enhanced soil enzyme activities and nutrient availability and promoted accumulation of defense-related metabolites in the rhizosphere.</p><p>Conclusions</p><p>A tailored cross-kingdom SynCom establishes a disease-suppressive, growth-promoting soil environment that mitigates wheat crown rot while improving yield components. These findings support microbiome engineering as a practical, sustainable strategy for wheat production and warrant field-scale validation and formulation development.</p>
Project description:To explore the ecological basis for multiple bacteria species coexistence, we set up three bacteria (Ruegeria pomeroyi DSS-3, Vibrio hepatarius HF70, and Thalassospira sp. HF15), either in monoculture or in co-cultures (in all combinations) for a 8 day growth-dilution cycles. At ~15h of day 4 (P4) and day 8 (P8) of growth-dilution cycles, we examined transcriptomic responses of these bacteria. Differential gene expressions were used to generate hypothesis about ecological and physiological responses of one in the presence of another/other bacteria.
Project description:This study evaluated the transcriptomic profiles of Arabidopsis thaliana (Col-0) plants grown along four SynCom treatments that induced differential primary root growth. Treatments Dropout Variovorax and DropoutVariovoraxBurkholderia induced primary root growth inhibition (RGI), while treatments Full and DropoutBurkholderia mantained a stereotypical long primary root.
Project description:To explore the usefulness of Brachypodium distachyon for drought studies, a reproducible in soil drought assay was developed. Spontaneous soil drying led to a 45% reduction in leaf size, and this most mostly due to a decrease in cell expansion, whereas cell division remained largely unaffected by drought. To investigate the molecular basis of the observed leaf growth reduction, Brachypodium leaf 3 was dissected in three zones, namely the proliferation, expansion and mature zone, and subjected to transcriptome analysis using a Affymetrix whole-genome tiling array. This approach allowed us to highlight that transcriptome profiles of different developmental leaf zones respond differently to drought. Several genes and biological processes involved in drought tolerance were identified. Mainly, we observed an increased energy availability in the proliferation zone along with an upregulation of sterol synthesis that may influence membrane fluidity.
