Bacterial genetic determinants preventing fungal dysbiosis in Arabidopsis roots

• Applicant: Stephane Hacquard, Ph.D.
• Subject Area: Organismic Interactions, Chemical Ecology and Microbiomes of Plant Systems ; Microbial Ecology and Applied Microbiology
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 402123107

In this project, we aim at tracking the contribution of individual bacterial strains to the protective activity phenotype and at identifying bacteria-encoded mechanisms that modulate fungal load and/or community composition at the root interface. The major objective is to characterize multiple (strain-specific and/or conserved) competitive mechanisms that act independently or synergistically to prevent fungal dysbiosis in A. thaliana roots. Furthermore, the identification of bacteria-encoded mechanisms that supplement the host immune system to modulate fungal abundance and diversity in plant roots is also key for developing novel biocontrol strategies to prevent fungal diseases in plants. Reducing functional redundancies between SynCom members through the use of a simplified, yet representative multi-kingdom microbial consortium is key to mechanistically assess the extent to which competition between bacterial root commensals and fungi affect plant health in a community context. By using a multifaceted approach that includes microbiota reconstitution and manipulation experiments, microbial profiling methods, high-resolution genome-resolved metatranscriptomics, as well as high-throughput screens and functional studies, we aim at identifying key bacterial functions induced upon fungal competition sensing that modulate fungal growth and diversity at the root interface, thereby maintaining fungal-host homeostasis in roots.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2125: Deconstruction and Reconstruction of the Plant Microbiota "DECRyPT"