Taxonomic Diversity of the Microbial Community in the Kuchiger Thermal Spring (Baikal Rift Zone)

Abstract—

The hydrochemical and microelement composition of water and bottom sediments has been determined in the Kuchiger thermal spring (Baikal rift zone). The entry of chemicals with groundwater and high temperatures create favorable and specific conditions for the development of microorganisms. The taxonomic diversity of the microbial community of water and bottom sediments is studied using the analysis of 16S rRNA gene aplicons, and 107 619 nucleotide sequences assigned to 211 operational taxonomic units (OTUs) are analyzed. In the studied samples of water and bottom sediments, bacteria dominate; representatives of archaea account for 0.2–3.1%. The phylum Proteobacteria dominate in microbial communities. The subdominants in the studied samples were the phyla Firmicutes, Chloroflexi, Nitrospirae, Acetothermia, and Actinobacteria, where their ratio vary depending on the biotope. One characteristic feature of the microbial community in the Kuchiger thermal spring is the dominance of chemolithotrophic bacteria.