Antibiotic resistance in mucosal bacteria from high Arctic migratory salmonids

The Phenomenon of Antibiotic Resistance in the Polar Regions: An Overview of the Global Problem

The increasing prevalence of antibiotic resistance is a global problem in human and animal health. This leads to a reduction in the therapeutic effectiveness of the measures used so far and to the limitation of treatment options, which may pose a threat to human health and life. The problem of phenomenon of antibiotic resistance affects more and more the polar regions. This is due to the increase in tourist traffic and the number of people staying at research stations, unmodernised sewage systems in inhabited areas, as well as the migration of animals or the movement of microplastics, which may contain resistant bacteria. Research shows that the presence of antibiotic resistance genes is more dominant in zones of human and wildlife influence than in remote areas. In a polluted environment, there is evidence of a direct correlation between human activity and the spread and survival of antibiotic-resistant bacteria. Attention should be paid to the presence of resistance to synthetic and semi-synthetic antibiotics in the polar regions, which is likely to be correlated with human presence and activity, and possible steps to be taken. We need to understand many more aspects of this, such as bacterial epigenetics and environmental stress, in order to develop effective strategies for minimizing the spread of antibiotic resistance genes. Studying the diversity and abundance of antibiotic resistance genes in regions with less anthropogenic activity could provide insight into the diversity of primary genes and explain the historical evolution of antibiotic resistance.

Tetracycline Resistance Genes in the Traditional Swedish Sour Herring surströmming as Revealed Using qPCR

Antibiotic resistance (AR) represents a global concern for human health. To the best of the authors' knowledge, no study addressing AR in surströmming, a traditional Swedish fermented herring, has been performed to date. The aim of the present research was to study the prevalence of tet(O), tet(S), tet(W), tet(K), and tet(M) genes encoding for resistance to tetracycline using quantitative PCR (qPCR) applied to ready-to-eat surströmming samples collected from three producers located in Sweden. The tet(M) gene was found in all the analyzed samples, and it was also the most abundant among the tested tet genes; moreover, tet(O) was the least frequently detected gene. As a general trend, all the analyzed samples showed a high occurrence of the target genes, with slight variations among the producers. A principal component analysis did not reveal any separation among the samples or producers. All the collected data allowed for a drawing of a first picture of the occurrence of tetracycline resistance genes in ready-to-eat surströmming samples. Since no differences among the samples manufactured by the different producers were observed, it is likely that the detected genes were homogeneously spread among the microbial species shared by the herrings used as raw materials. Moreover, it can be hypothesized that the presence of the detected genes was also the result of a selective pressure of the natural marine environment on the herrings' gut microbiota and, hence, on the pro-technological microorganisms responsible for the fermentation of surströmming. However, the contribution of the manufacturers to the contamination of the processed herrings cannot be excluded.