ИСТИНА

Nanopore sequencing is a dynamically developing technology capable of generating large amounts of nucleic acid sequence data with less labor, time, and money compared to other sequencing technologies. It yields a larger volume of information due to increased average read length and the ability to detect modified bases. This is especially relevant for environmental monitoring tasks, in particular for assessing the anthropogenic impact on natural communities of microorganisms invisible to the eye. These include algal-bacterial communities that live in water treatment plants and participate in the biological treatment of wastewater from excess organic waste and nutrients (phosphorus and nitrogen). Using metagenomic analysis methods based on nanopore sequencing data, changes in the taxonomic composition and functional profile of the algal-bacterial community were shown when simulating the entry of drugs into wastewater – broad-spectrum antibiotics (using the example of ceftriaxone) and non-steroidal anti-inflammatory drugs (using the example of diclofenac). The results of metagenomic analysis based on long reads obtained from nanopore sequencing and classical methods of environmental monitoring, including metabarcoding based on short reads from second generation sequencing, were compared. It has been shown that under the influence of medicinal substances, the algal-bacterial community is enriched with antibiotic-resistant bacteria. At the same time, despite the continued rate of phosphorus removal, the community’s potential for the removal of nutrients is decreasing. Simultaneous exposure to ceftriaxone and excess nutrients in the wastewater led to the maximum enrichment of antibiotic-resistant organisms, as well as the replacement of cyanobacteria originally present in the community with eukaryotic microalgae.