Exploring a cradle of multi-resistant bacteria -- antibiotic resistance in soil and its link to different land use types and intensities

• Applicant: Dr. Heiko Nacke
• Subject Area: Microbial Ecology and Applied Microbiology
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 325202041

Human pathogenic bacteria resistant to multiple classes of antibiotics pose risks to public health and are considered as one of the major global challenges within the 21st century. Some of the antibiotic resistance genes carried by these bacteria have been traced to soil origins and can potentially spread via e.g., groundwater or wildlife. In this project, the dynamics of soil`s antibiotic resistance pool will be analyzed along a wide array of land use types and intensities within the three Biodiversity Exploratories. To provide robust assessment of land use impacts on antibiotic resistance gene abundance levels, real-time quantitative PCR-based analysis of soil DNA derived from all grassland EP and forest VIP plots will be carried out. Land use-induced changes in community profiles of antibiotic-resistant soil bacteria are deciphered within a microcosm experiment, including assessment and quantification of bacterial community dynamics. Another focus is the identification of shifts in plasmid occurrence accompanying different land use types and intensities, as these mobile genetic elements are a major source for antibiotic resistance and contribute to its dissemination. In this context, we will determine the abundance of IncP-1 plasmids, which can carry multiple antibiotic resistance determinants and allow gene transfer between distantly related bacteria. Overall diversity of antibiotic resistance gene-harboring circular plasmids will be estimated by applying a long-read sequencing approach. Moreover, function-based screening of previously constructed soil metagenomic libraries will be performed, to discover differences in richness of antibiotic resistance genes and mechanisms associated with land use intensity. To predict possible consequences of anthropogenic activities on spread of multi-resistant bacteria, comprehensive knowledge on antibiotic resistance in soil affected by different land use types and intensities is urgently required. This project will provide detailed information about land use impacts on soil`s antibiotic resistance reservoir and transfer potential. Furthermore, close collaborations within the Biodiversity Exploratories research platform will elucidate linkages between antibiotic resistance in soil and abiotic as well as biotic factors such as heavy metal concentrations or abundance of fungal taxa.

• DFG Programme: Infrastructure Priority Programmes
• Subproject of: SPP 1374: Biodiversity Exploratories