Dataset Information

Metagenomic data of the microbial community of the chemocline layer of the meromictic subarctic Lake Bolshie Hruslomeny, North European Russia.

ABSTRACT: The Lake Bolshie Hruslomeny is located on the shores of the Kandalaksha Bay of the White Sea, North European Russia. This lake, formed from the sea bay and still retaining the subsurface connection with the sea, is meromictic, with a fresh oxygenated upper layer and an anoxic brackish hypolimnion with high concentrations of methane and hydrogen sulphide. To characterize the microbial communities involved in the carbon and sulfur cycles in the lake, we sequenced the metagenome of a water sample collected at the chemocline level. At the phylum level, Chlorobi, Proteobacteria, Bacteroidetes and Firmicutes were the most numerous groups. The obtained data will help investigate the diversity and ecological role of the microbial community in the Lake Bolshie Hruslomeny and provide insight into the biogeochemical processes in subarctic lakes. The raw sequencing data is available from the NCBI Sequence Read Archive (SRA) database under the BioProject PRJNA503531.

SUBMITTER: Kadnikov VV

PROVIDER: S-EPMC6660547 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Metagenomic data of the microbial community of the chemocline layer of the meromictic subarctic Lake Bolshie Hruslomeny, North European Russia.

Kadnikov Vitaly V VV Savvichev Alexander S AS Mardanov Andrey V AV Beletsky Alexey V AV Ravin Nikolai V NV Pimenov Nikolai V NV

Data in brief 20190302

The Lake Bolshie Hruslomeny is located on the shores of the Kandalaksha Bay of the White Sea, North European Russia. This lake, formed from the sea bay and still retaining the subsurface connection with the sea, is meromictic, with a fresh oxygenated upper layer and an anoxic brackish hypolimnion with high concentrations of methane and hydrogen sulphide. To characterize the microbial communities involved in the carbon and sulfur cycles in the lake, we sequenced the metagenome of a water sample c ...[more]

PMID: 31372445

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Project description:We analyzed the variation with depth in the composition of members of the domain Bacteria in samples from alkaline, hypersaline, and currently meromictic Mono Lake in California. DNA samples were collected from the mixolimnion (2 m), the base of the oxycline (17.5 m), the upper chemocline (23 m), and the monimolimnion (35 m). Composition was assessed by sequencing randomly selected cloned fragments of 16S rRNA genes retrieved from the DNA samples. Most of the 212 sequences retrieved from the samples fell into five major lineages of the domain Bacteria: alpha- and gamma-Proteobacteria (6 and 10%, respectively), Cytophaga-Flexibacter-Bacteroides (19%), high-G+C-content gram-positive organisms (Actinobacteria; 25%), and low-G+C-content gram-positive organisms (Bacillus and Clostridium; 19%). Twelve percent were identified as chloroplasts. The remaining 9% represented beta- and delta-Proteobacteria, Verrucomicrobiales, and candidate divisions. Mixolimnion and oxycline samples had low microbial diversity, with only 9 and 12 distinct phylotypes, respectively, whereas chemocline and monimolimnion samples were more diverse, containing 27 and 25 phylotypes, respectively. The compositions of microbial assemblages from the mixolimnion and oxycline were not significantly different from each other (P = 0.314 and 0.877), but they were significantly different from those of chemocline and monimolimnion assemblages (P < 0.001), and the compositions of chemocline and monimolimnion assemblages were not significantly different from each other (P = 0.006 and 0.124). The populations of sequences retrieved from the mixolimnion and oxycline samples were dominated by sequences related to high-G+C-content gram-positive bacteria (49 and 63%, respectively) distributed in only three distinct phylotypes, while the population of sequences retrieved from the monimolimnion sample was dominated (52%) by sequences related to low-G+C-content gram-positive bacteria distributed in 12 distinct phylotypes. Twelve and 28% of the sequences retrieved from the chemocline sample were also found in the mixolimnion and monimolimnion samples, respectively. None of the sequences retrieved from the monimolimnion sample were found in the mixolimnion or oxycline samples. Elevated diversity in anoxic bottom water samples relative to oxic surface water samples suggests a greater opportunity for niche differentiation in bottom versus surface waters of this lake.

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Dataset Information

Metagenomic data of the microbial community of the chemocline layer of the meromictic subarctic Lake Bolshie Hruslomeny, North European Russia.

Publications

Metagenomic data of the microbial community of the chemocline layer of the meromictic subarctic Lake Bolshie Hruslomeny, North European Russia.

Similar Datasets

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