The role of cyanobacteria in aquatic resistome

The aquatic environment is a reservoir of antibiotics, pathogenic and native microorganisms, and antibiotic resistance (AR) genes, constituting a key compartment in the One Health approach. Thus, the problem of AR is no longer restricted to bacterial pathogens, but is a consequence of the interplay between distinct clinical and environmental drivers. In the project “ExplorAR – Exploring the Aquatic Resistome”, we have been investigating the putative role of cyanobacteria (CB) in freshwater resistome, using a multidisciplinary approach, based on phenotypic/genotypic/genomic tools. In this presentation we disclose the main project outputs: i) development of a microdilution-based antibiotic susceptibility assay for CB; ii) establishment of antibiotic susceptibility profile of CB genus/species; iii) identification of CB strains with reduced susceptibility to multiple antibiotic classes; iv) identification of AR genes in CB genomes. Presently, we are profiling AR of CB-associated bacteria and mapping the occurrence of CB and AR genes in surface freshwater reservoirs by HTS approaches. Overall, ExplorAR strongly supports the hypothesis that CB are environmental players in AR emergence and dissemination in water environments, contributing to the AR problematic. Work supported by the project “ExplorAR_Exploring the Aquatic Resistome” (PTDC/BIABMA/31451/2017), funded by Portuguese Foundation for Science and Technology (FCT/MCTES), through national funds (PIDDAC)