Microbial communities in the estuarine water areas of the rivers in the southeastern part of Lake Baikal

Abstract

Using the Illumina MiSeq platform, we have studied the diversity of bacteria and archaea in three rivers of the southeastern end of Lake Baikal in the under-ice period of 2018. In analysed 16S rRNA gene libraries of all rivers, we have identified sequences of 12 bacterial phyla: Actinobacteria, Bacteroidetes, Cyanobacteria, Elusimicrobia, Epsilonbacteraeota, Fibrobacteres, Firmicutes, Omnitrophicaeota, Patescibacteria, Planctomycetes, Proteobacteria, and Verrucomicrobia. The contribution of minor taxa to the microbiomes from the estuaries of the rivers Solzan and Bolshaya Osinovka is more significant. Three phyla (Thaumarchaeota, Euryarchaeota and Crenarchaeota) and one superphylum (DPANN) represent archaea. The diversity of bacteria and archaea in the investigated ecotopes has its specifics and is not identical to that found in the pelagic zone of Southern Baikal. Bacteria show phylogenetic diversity at the level of families and genera, whereas archaea – at the level of phyla. In the microbiomes, we have identified microorganisms involved in various stages of transformation of organic and inorganic substances.