Antibiotics at the soil-plant nexus: High-resolution insights into bacterial biotransformation, effects on bacterial metabolic activities and consequences for plant health (ANTIRESIST)

• Applicant: Dr. Anja Worrich
• Subject Area: Soil Sciences
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 530107960

Humanity faces the enormous challenge of increasing agricultural productivity for a rapidly growing population while reducing the ecological footprint on our ecosystems. However, the use of organic fertilizers to increase crop productivity results in large amounts of antibiotics entering agricultural soils due to massive use in livestock production. Despite intensive research on the biodegradation and effects of antibiotics on bacterial communities in soil-plant systems, there are still specific knowledge gaps that need to be filled to better assess the ecological risks of antibiotics. ANTIRESIST has two objectives: First, to obtain generalizable results from existing, globally distributed studies, and second, to overcome the previous challenges in the research field through high-resolution measurements at the single-cell level. To achieve these goals, I propose to 1) conduct meta-analyses that provide a quantitative synthesis of existing knowledge and enable the identification of drivers modulating the effects of antibiotics on bacterial diversity and the prevalence of antibiotic resistance in soil-plant systems; 2) apply a single-cell metabolic activity-based approach in combination with phylogenetic identification to better resolve the biotransformation of a model antibiotic and its effects on the activity of soil and plant microbiomes; and 3) conduct a controlled greenhouse experiment to investigate the completely unknown effects of the antibiotic on plant microbiome-mediated immunity to a parasitic nematode and identify bacterial key players. By reusing existing knowledge, accounting for heterogeneities in bacterial community distribution and activity, and investigating cascading effects on plant health, ANTIRESIST provides the basis for developing new hypotheses and can contribute to the risk assessment of antibiotic residues in agroecosystems.

• DFG Programme: Independent Junior Research Groups