Taxonomic and Functional Diversity of Microbial Communities in Saline Lakes of Barguzin Depression (Russia) Assessed Using Shotgun Sequencing

The taxonomic composition and functional diversity of microbial communities in Lakes Gudzhirganskoe and Nukhe-Nur (Barguzin Depression, Russia) have been studied for the first time using shotgun sequencing. Taxonomic analysis revealed a diverse phylogenetic composition dominated by bacteria (96.8% in Lake Gudzhirganskoe and 99.5% in Lake Nukhe-Nur). In both lakes, the most prevalent phyla were Pseudomonadota, Bacillota, and Bacteroidota. On the genus level, the composition of the communities differed significantly, probably due to the hydrochemical regime of the lakes. It was found that the microbial communities of the studied lakes were predominantly represented by halophilic and alkaliphilic microorganisms. In spite of the taxonomic differences, these microbial communities had a similar functional profile with minor variations and demonstrated the potential to mediate a wide range of important biogeochemical processes.