Diversity and Metabolism of Microbial Communities in a Hypersaline Lake along a Geochemical Gradient

Abstract

In the south of western Siberia (Russia), there are many unique and unexplored soda, saline, and freshwater lakes. In this study, the results are presented on microbial diversity, its metabolic potential, and their relation with a set of geochemical parameters for a hypersaline lake ecosystem in the Novosibirsk region (Oblast). The metagenomic approach used in this work allowed us to determine the composition and structure of a floating microbial community, the upper layer of silt, and the strata of bottom sediments in a natural saline lake via two bioinformatic approaches, whose results are in good agreement with each other. In the floating microbial community and in the upper layers of the bottom sediment, bacteria of the Proteobacteria (Gammaproteobacteria), Cyanobacteria, and Bacteroidetes phyla were found to predominate. The lower layers were dominated by Proteobacteria (mainly Deltaproteobacteria), Gemmatimonadetes, Firmicutes, and Archaea. Metabolic pathways were reconstructed to investigate the metabolic potential of the microbial communities and other hypothetical roles of the microbial communities in the biogeochemical cycle. Relations between different taxa of microorganisms were identified, as was their potential role in biogeochemical transformations of C, N, and S in a comparative structural analysis that included various ecological niches.

Microbial Diversity and Authigenic Mineral Formation of Modern Bottom Sediments in the Littoral Zone of Lake Issyk-Kul, Kyrgyz Republic (Central Asia)

“…Of particular interest is the study of the microbiological characteristics of saline lakes of recreational importance. A comprehensive study of the biogeochemical properties of the bottom sediments of these lakes is one of the current areas of modern microbiology [6][7][8]. In brackish and saline lakes, high mineral content ensures a massive development of microbiota, especially in coastal zones, where the number and species composition of aquatic microorganisms increases dramatically [4].…”

“…Studies [2,6,9,14,[18][19][20][21] show that bottom sediments of saline lakes in Eurasia contain a number of authigenic minerals: calcite, pyrite, rhodochrosite, siderite, barite, etc., which are formed with the direct participation of microorganisms. This process proceeds especially intensively in the upper intervals of bottom sediments in the littoral zone.…”

Assessment of the Microbiome Diversity in Lakes of the West Kazakhstan Region

“…Our study found that unclassi ed bacteria, i.e.,Proteobacteria, Bacteroidota, and Actinobacteriota, were the dominant species in all three lakes studied: Aidyn, Brusyanoe, and Rybny Sakryl lakes. These bacterial species are common in majority of the lakes [25,26,27,28,29,30,31,32].…”

Metagenome-assembled genomes provide insight into the microbial taxonomy and ecology of the Buhera Soda Pans, Zimbabwe

“…The extreme conditions existent in soda pans and lakes modify their microbial communities, leading to the dominance of extremophiles, with halophiles, alkaliphiles and haloalkaliphiles often dominating these microbiomes (Bryanskaya et al ., 2022). The ability of different microbial taxa to thrive under the alkaline and saline conditions of soda pans stimulate interest among microbiologists about such microbial ecosystems, and elevate the possibility that some of the microorganisms that inhabit these environments have potentially useful applications.…”