Probing Antibiotic Residues and Resistance transfer in Aquatic Environments

The project aims to study bacteria, antibiotic resistance genes (ARGs) and antibiotic residues in groundwater, surface water, marine waterenvironments in the North Sea and Atlantic including posrt and aquaculture facilities. Samples will be collected from sites with high and low suspected loads of antibiotic residues. Culture-based and sequencing-based methods will be used to identify ARGs. Transfer of ARG-containing plasmids will be analysed using indicator bacteria Escherichia coli, Vibrio spp, and Shewanella algae as recipients. LC-MS/MS will be used to quantify the levels of different ntibiotics in the collected samples. We hypothezise that local water microbiota, antibiotic residues and recipient species will affect the type of plasmids transferred. The effects of the acquired plasmids on the physiology of our bacterial models will be analysed in experiments lab systems, and their influence on fitness and virulence in a live host will be studied by host interactions in a shrimp (Artemisia) model. The project will determine common ARG plasmids circulating in European waters and their inherent properties as a fundament to understand and prevent their dissemination.



Human Health, Emerging Pollutants, Pathogens, Antimicrobial Resistance, Aquatic Ecosystems


Achievements so far

PARRTAE has successfully collected bacterial isolates from different water sites in Sweden, Norway, Belgium, Gran Canaria and marine environments. More than 500 isolates from lakes, rivers and wastewater treatment plants have been analysed for antibiotic resistance. Preliminary results indicate low levels of indicator bacteria (E. coli) and antibiotic resistance genes (ARGs) in areas with minimal anthropogenic impact, while sites with human or livestock impact show higher bacterial levels and ARG presence, including some extended spectrum beta-lactamases (ESBL). In contrast, the majority of E. coli isolates from wastewater treatment plants are ESBL-positive and multiresistant. Antibiotic residue studies show the presence of lincomycin, sulfonamides, trimethoprim, amoxicillin and florfenicol in Belgian surface waters.

The project plans to collect and analyse data from additional sites, while the next phase will involve sequencing of selected resistant isolates using both short and long read methods. More than 50 isolates have already undergone whole genome sequencing. Ongoing efforts include studies of horizontal gene transfer of ARGs and the effect of mobile elements on recipient bacteria, as well as brine shrimp models.

The results are consistent with previous findings, indicating the common presence of multidrug-resistant bacteria in wastewater treatment plants and heavily impacted surface waters. However, preliminary results from less impacted water sources suggest lower levels of ARGs in naturally occurring waterborne E. coli and Shewanella.

If you're interested in scientific publications associated with PARRTEA, click here.


Project Coordinator:
Dr. Åsa Sjöling,
Karolinska Institute, Sweden


Communication & Dissemination Contact:
Jonatan Martin Rodriguez


Partner Institutions:
Universidad de Las Palmas de Gran Canaria – Spain

Flanders Research Institute for Agriculture, Fisheries and Food (IVLO) – Belgium

Norwegian University of Science and Technology – Norway

Swedish University of Agricultural Sciences – Sweden