APPLICATION OF 18S METAGENOMIC SEQUENCING FOR EVALUATING PROTISTAN DIVERSITY IN HYPERSALINE WATER BODIES
Objective. Evaluation of the diversity of protists in the hypersaline lakes with high-throughput sequencing. Materials and methods. For the study samples of water were taken from hypersaline lakes Tuzluchnoe (Orenburg region) and Kulat (Chelyabinsk region). Total DNA was extracted by a combined method, including mechanical homogenization and enzymatic lysis. 18S metagenomic sequencing of the DNA libraries was conducted in the MiSeq sequencer (Illumina). Data analysis was carried out using a complex of bioinformatic programs. Results. For the first time, diversity of eukaryotes has been studied with high-throughput sequencing in two similar in mineralization lakes Tuzluchnoe (Orenburg region) and Kulat (Chelyabinsk region). Representatives of the phylum Chlorophyta prevailed in Tuzluchnoe Lake. Green algae of the genus Nannochloris were predominant. Many of the OTU revealed were not identified and possibly represent new species. Species diversity of protists in Kulat Lake was narrow. The dominant OTUs were represented by the fairy shrimps Branchiopoda. Conclusion. Species richness of the eukaryotes in Tuzluchnoe Lake was significant, 48 OTU were recorded, 45 of which were classified as protists, as well as 17 OTUs in Kulat Lake were recorded, including 4 OTUs of protists. That fact is apparently associated with mass development of Artemia salina in Kulat Lake. Thus, modern molecular genetic methods allow to obtain complete information on the composition of eukaryotic communities in salt water bodies.