Project description:Global warming has become a critical challenge to food safety, causing severe yield losses of major crops worldwide. Here, we report that the endophytic bacterium Enterobacter sp. SA187 induces thermotolerance of crops in a sustainable manner. Microbiome diversity of wheat plants is positively influenced by SA187 in open field agriculture, indicating that beneficial microbes can be a powerful tool to enhance agriculture in open field agriculture.
Project description:Global warming and heat stress belong to the most critical environmental challenges to agriculture worldwide, causing severe losses of major crop yields. In present study we report that the endophytic bacterium Enterobacter sp. SA187 protects Arabidopsis thaliana to heat stress. To understand the mechanisms at molecular level we performed RNA-seq
Project description:Enterobacter sp. SA187 is a plant growth-promoting bacterium (PGPB) that promotes growth of the crop plant alfalfa under saline irrigation and desert farming conditions. SA187 also enhances salt tolerance of the model plant Arabidopsis thaliana under in vitro conditions. In the present study, we used a transcriptomic approach to elucidate the mechanisms underlying plant growth promotion by SA187 under salt stress. Compared to free-living SA187, a massive metabolic reprogramming of SA187 occurs upon association with Arabidopsis. This effect was largely independent of the plant growth condition (non-salt or salt stress). Our data revealed pronounced changes in gene expression of proteins involved in cell signaling, chemotaxis, flagella biosynthesis, quorum sensing and biofilm formation. Also, upon plant interaction, a complete reprograming of nutrients acquisition and the central carbon metabolism of SA187 was observed. Moreover, in accordance with the previously identified role of bacterially produced 2-keto-4-methylthiobutyric acid (KMBA) in mediating salt stress tolerance, the sulfur metabolism of SA187 was strongly induced. Overall, our results give a deep insight into the metabolic and signaling pathways involved in the transition from free-living to a plant-associated PGPB life style of SA187.
Project description:Microbes of the root-associated microbiome contribute to improve resilience and fitness of plants. In this study, the interaction between the salt stress tolerance-inducing beneficial bacterium Enterobacter sp. SA187 and Arabidopsis was investigated with a special focus on the plant immune system. Among the immune signalling mutants, the Lys-motif receptors LYK4 strongly affected the beneficial interaction. Overexpression of the chitin receptor components LYK4 compromised the beneficial effect of SA187 on Arabidopsis. Transcriptome analysis revealed that the role of LYK4 in immunity is intertwined with a function in remodeling defense responses. Overall, our data indicate that components of the plant immune system are key elements in mediating beneficial metabolite-induced plant abiotic stress tolerance.
Project description:Recent studies have shown that several plant species require microbial associations for stress tolerance and survival. In this work, we show that the desert endophytic bacterium Enterobacter sp. SA187 enhances yield and biomass of alfalfa in field trials, revealing a high potential for improving desert agriculture. To understand the underlying molecular mechanisms, we studied SA187 interaction with Arabidopsis thaliana. SA187 colonized surface and inner tissues of Arabidopsis roots and shoots and conferred tolerance to salt and osmotic stresses. Transcriptome, genetic and pharmacological studies revealed that the ethylene signaling pathway plays a key role in mediating SA187-triggered abiotic stress tolerance to plants. While plant ethylene production is not required, our data suggest that SA187 induces abiotic stress tolerance by bacterial production of 2-keto-4-methylthiobutyric acid (KMBA), known be converted into ethylene in planta. These results reveal a part of the complex molecular communication process during beneficial plant-microbe interactions and unravel an important role of ethylene in protecting plants under abiotic stress conditions.
Project description:Although some mechanisms are known how plant growth beneficial bacteria help plants to grow under stressful conditions, we still know little how the metabolism of host plants and bacteria is coordinated during the establishment of functional interaction. In the present work, using single and dual transcriptomics, we studied the reprograming of metabolic and signaling pathways of Enterobacter sp. SA187 with Arabidopsis thaliana during the change from free-living to endophytic host-microbe interaction. We could identify major changes in primary and secondary metabolic pathways in both the host and bacteria upon interaction, with an important role of the sulfur metabolism and retrograde signaling in mediating plant resistance to salt stress. Also, we studied the effect of SA187 endogenous compounds and its role on sulfur metabolism and consequently salt tolerance. These data should help future research in the field of beneficial plant-microbe interactions for developing sophisticated strategies to improve agriculture of crops under adverse environmental conditions. transcriptome of Arabidopsis thaliana organs with beneficial microbe, beneficial microbe endogenous compound, and ethylene precursor
