Genes of past, present and future: does legacy pollution contribute to antibiotic resistance in industrialised estuaries?

The ability to compare different pollution conditions among stratified layers in estuarine sediments allow us to determine key contributing factors affecting antibiotic resistance (AMR) in microbial communities. This is a unique approach of investigating resistance traits will generate a wealth of information about how our past industrial actions may impact public and environmental health now and/or the near future.

Sediments have been collected from the Clyde, Scotland, at various depths and have been analysed for physicochemical properties (pH, conductivity, organic matter, particle size), potential pollutants (metals and polycyclic aromatic hydrocarbons) as well as prokaryotic and eukaryotic biome.

Our research has found that potentially toxic elements (e.g. Cr and Pb) increase with depth, indicative of historical uses. To date, our analysis correlates with an increase in efflux pump genes in prokaryotes(1-4). The growth difference of Acanthamoeba on the other hand suggests the Cu may aid the prevalence of Acanthamoeba and the speed at which it grows whilst Mg has an inhibitory effect.

Our results strongly indicate that environmental pollution is responsible for the development of AMR and that protists (e.g. Acanthamoeba) are also affected by environmental conditions. Acanthamoeba are also known to harbour bacteria which may also affect the emergence of antimicrobial resistance.