Metagenomic Assessment of Prokaryotic Diversity within Hypersaline Tuz Lake, Turkey

Abstract

Tuz Lake is the second biggest lake with an extreme hypersaline environment (over 32% (w/v) salt) in Turkey. It is reported that the lake was of marine origin, and its formation began with tensional movements during the Late Cretaceous and the Late Eocene. We conducted this research to determine the prokaryotic diversity of Tuz Lake by metagenomics approach, which is 16S rRNA amplicon sequencing of microbial communities in their natural environments. Hence, next-generation sequencing and then bioinformatic analysis was used to investigate the microbial structure of halophilic Bacteria and Archaea in Tuz Lake. Metagenomic analysis of reads revealed that all the archaeal populations in Tuz Lake belonged to the Euryarchaeota and Nanoarchaeaeota phyla. Haloquadratum (34%), Haloparvum (31%), Halonotius (7%), Halorubrum (3%), Halapricum (2%), Halobellus (3%), Natronomonas (1%), Halococcus (1%), and Halobacterium (1%) were found as the dominant archaeal genera. The most abundant and diverse bacterial phyla were Bacteroidetes and Proteobacteria. The remaining bacterial taxa were assigned to Acetothermia, Cyanobacteria, Firmicutes, and Halanaerobiaeota. Salinibacter (3%), uncultured microorganisms (1%), Pseudomonas (<1%), Arhodomonas (<1%), Halorhodospira (<1%), Chromobacterium (<1%) were the most common genera in bacterial diversity. Monthly and seasonal potential interactions among environmental factors and taxa were investigated. It was detected that several environmental factors such as temperature, salinity, and drought might have significant effects on microbial richness.

Seasonal dynamics of eukaryotic microbial diversity in hypersaline Tuz Lake characterized by 18S rDNA sequencing

“…It was also indicated that Ciliophora was one of the predators of bacteria and involved in symbiosis with algae (Chen et al, 2020). Moreover, the Bacteroidetes and Proteobacteria phylum, the most abundant bacterial phylum in Tuz Lake, showed the highest abundance in winter while decreasing in summer (Doğan & Kocabaş, 2021), similar to Ciliapore abundance. High temperature in summer and fall may adversely affect the distribution of Ciliapore in Tuz Lake as well as biological factors such as bacterial abundance (Table 1).…”

“…The prokaryotic microbial diversity in Tuz Lake has been well described by 16S rDNA sequencing (Akpolat et al, 2021;Çınar & Mutlu, 2020;Doğan & Kocabaş, 2021;Oyewusi et al, 2021). However, the characterization and seasonal variation of the eukaryotic microbial community with environmental parameters in Tuz Lake is poorly understood.…”

“…I G U R E 6 Principal coordinate analysis of samples based on weighted UniFrac distance matrix (Green: Winter, Blue: Spring, Orange: Summer, Red: Fall).T A B L E 1 Environmental parameters of sampling sites in Tuz Lake(Doğan & Kocabaş, 2021).…”

Microbial community structure and shift pattern of industry brine after a long-term static storage in closed tank

“…Salinibacter spp. generally, requires light-driven pumps for growth and maintenance of ion gradients across the cell membrane (Dogan and Kocabaş, 2021). The low levels of genus Salinibacter in C1-3 may be attributed to relatively lower levels of solar radiation and lower temperatures (Kalwasinska et al, 2018).…”

Three New Plectolyngbya Species (Leptolyngbyaceae, Cyanobacteria) Isolated from Rocks and Saltern of the Republic of Korea

“…Hypersaline habitats are characterized as having a high salinity, high alkalinity, low oxygen concentration, and having halophilic microorganisms [2]. Halophilic cyanobacteria are known to be one of the major bacteria in high-salt concentration environments, such as hypersaline lakes, saline springs and soils, coastal hypersaline lagoons, and saltern evaporation ponds worldwide [2,3]. The halophilic cyanobacteria, a unicellular and filamentous species, form dense benthic mats in shallow solar salterns worldwide.…”