Auxotrophic enrichment in the rhizosphere: Unraveling bacterial responses to plant exudates in the context of nutrient limitation

• Grant number: 24/16079-0
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2025
• End date: February 29, 2028
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Simone Raposo Cotta
• Grantee: Simone Raposo Cotta
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated researchers: Elisa Korenblum ; Fernando Dini Andreote ; Noah Fierer ; Thierry Alexandre Pellegrinetti
• Associated scholarship(s): 25/07364-5 - Auxotrophic enrichment in the rhizosphere: Unraveling bacterial responses to plant exudates in the context of nutrient limitation, BP.MS

Abstract

Plants influence the bacterial community in rhizospheric soil by releasing compoundssuch as amino acids, which act as nutrients or signaling molecules. This can promote theselection of auxotrophic bacteria unable to synthesize these compounds. We propose thatthese auxotrophs are enriched in the rhizosphere due to the availability of amino acidsand that these organisms could help plants overcome nutritional stress. To test thishypothesis, we will employ a polyphasic approach that combines dependent andindependent cultivation methodologies to assess the bacterial community, evaluate theirauxotrophic profiles, and examine the consequences of these organisms' presence underboth control conditions and nutritional deficiency. Phosphorus will be used as the modelnutrient. Additionally, we will analyze plant-derived metabolites, such as amino acidsand vitamins, to understand their role in shaping bacterial communities. Theseexperiments aim to elucidate the prevalence of auxotrophic bacteria in the rhizosphereand their impact on plant resilience and resistance under nutritional stress. (AU)