COMPOSITION AND ACTIVITIES OF MICROBIAL COMMUNITIES INVOLVED IN CARBON,SULFUR, NITROGEN AND MANGANESE CYCLING IN THE OXIC/ANOXIC INTERFACE OF THE BLACK SEA

The present analytical review is dedicated to the current perspective of the issue of the Black sea xenobiotics pollution. The Black sea is extremely vulnerable to pollution impact, as it is a semi-closed water-body under the influence of significant inflow from the Danube, Dnipro and Dnister rivers. According to the recent data from the UNDP EMBLAS project 80 types of organic pollutants were identified in the Black Sea water samples. Those included 17 pesticides with the concentration above the safety thresholds both in the offshore and in the coastal waters. It has been previously shown that xenobiotics’ inflow results in taxonomic and functional shift of microbial communities inhabiting aquatic environment. Microbial-mediated degradation and biological pump control the polycyclic aromatic hydrocarbons’ flux in marine ecosystems, which prevents their accumulation in the food web. The data on xenobiotics pollution in both water column and sediments is summarized in the present review. The recent studies targeting the microbial communities’ role in biotransformation and translocation of substances with xenobiotic behavior are analyzed. The significance and topicality of the case-studies focusing on aquatic microbial communities functional response towards xenobiotics’ pollution is highlighted and the Black Sea ecosystem is suggested as the plausible example for addressing the above mentioned issues

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Quantification of microbial communities in subsurface marine sediments of the Black Sea and off Namibia

Frontiers in Microbiology ◽

10.3389/fmicb.2012.00016 ◽

2012 ◽

Vol 3 ◽

Cited By ~ 49

Author(s):

Axel Schippers

Keyword(s):

Microbial Communities ◽

Black Sea ◽

Marine Sediments ◽

The Black Sea

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Metagenomic 16s rRNA investigation of microbial communities in the Black Sea estuaries in South-West of Ukraine.

Acta Biochimica Polonica ◽

10.18388/abp.2015_1145 ◽

2016 ◽

Vol 63 (2) ◽

Cited By ~ 5

Author(s):

Oleksandra Bobrova ◽

Jon Bent Kristoffersen ◽

Anastasis Oulas ◽

Volodymyr Ivanytsia

Keyword(s):

16S Rrna ◽

Microbial Communities ◽

16S Rdna ◽

Black Sea ◽

Complex Analysis ◽

Bacterial Species ◽

Variable Region ◽

Illumina Miseq ◽

The Black Sea ◽

Rrna Gene

The Black Sea estuaries represent interfaces of the sea and river environments. Microorganisms that inhabit estuarine water play an integral role in all biochemical processes that occur there and form unique ecosystems. There are many estuaries located in the Southern-Western part of Ukraine and some of them are already separated from the sea. The aim of this research was to determine the composition of microbial communities in the Khadzhibey, Dniester and Sukhyi estuaries by metagenomic 16S rDNA analysis. This study is the first complex analysis of estuarine microbiota based on isolation of total DNA from a biome that was further subjected to sequencing. DNA was extracted from water samples and sequenced on the Illumina Miseq platform using primers to the V4 variable region of the 16S rRNA gene. Computer analysis of the obtained raw sequences was done with QIIME (Quantitative Insights Into Microbial Ecology) software. As the outcome, 57970 nucleotide sequences were retrieved. Bioinformatic analysis of bacterial community in the studied samples demonstrated a high taxonomic diversity of Prokaryotes at above genus level. It was shown that majority of 16S rDNA bacterial sequences detected in the estuarine samples belonged to phyla Cyanobacteria, Proteobacteria, Bacteroidetes, Actinobacteria, Verrucomicrobia, Planctomycetes. The Khadhzibey estuary was dominated by the Proteobacteria phylum, while Dniester and Sukhyi estuaries were characterized by dominance of Cyanobacteria. The differences in bacterial populations between the Khadzhibey, Dniester and Sukhyi estuaries were demonstrated through the Beta-diversity analysis. It showed that the Khadzhibey estuary's microbial community significantly varies from the Sukhyi and Dniester estuaries. The majority of identified bacterial species is known as typical inhabitants of marine environments, however, for 2.5% of microbial population members in the studied estuaries no relatives were determined.

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The suspended small-particle layer in the oxygen-poor Black Sea: a proxy for delineating the effective N<sub>2</sub>-yielding section

Biogeosciences ◽

10.5194/bg-17-6491-2020 ◽

2020 ◽

Vol 17 (24) ◽

pp. 6491-6505

Author(s):

Rafael Rasse ◽

Hervé Claustre ◽

Antoine Poteau

Keyword(s):

Microbial Communities ◽

Black Sea ◽

Small Particle ◽

The Black Sea ◽

Published Data ◽

Strong Correlations ◽

Particle Layer ◽

Subsurface Waters ◽

Sulfur Oxidizing ◽

Particle Backscattering

Abstract. The shallower oxygen-poor water masses of the ocean confine a majority of the microbial communities that can produce up to 90 % of oceanic N2. This effective N2-yielding section encloses a suspended small-particle layer, inferred from particle backscattering (bbp) measurements. It is thus hypothesized that this layer (hereafter, the bbp-layer) is linked to microbial communities involved in N2 yielding such as nitrate-reducing SAR11 as well as sulfur-oxidizing, anammox, and denitrifying bacteria – a hypothesis yet to be evaluated. Here, data collected by three BGC-Argo floats deployed in the Black Sea are used to investigate the origin of this bbp-layer. To this end, we evaluate how the key drivers of N2-yielding bacteria dynamics impact the vertical distribution of bbp and the thickness of the bbp-layer. In conjunction with published data on N2 excess, our results suggest that the bbp-layer is at least partially composed of the bacteria driving N2 yielding for three main reasons: (1) strong correlations are recorded between bbp and nitrate; (2) the top location of the bbp-layer is driven by the ventilation of oxygen-rich subsurface waters, while its thickness is modulated by the amount of nitrate available to produce N2; and (3) the maxima of both bbp and N2 excess coincide at the same isopycnals where bacteria involved in N2 yielding coexist. We thus advance that bbp and O2 can be exploited as a combined proxy to delineate the N2-yielding section of the Black Sea. This proxy can potentially contribute to refining delineation of the effective N2-yielding section of oxygen-deficient zones via data from the growing BGC-Argo float network.

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The suspended small-particles layer in the suboxic Black Sea: a proxy for delineating the effective N<sub>2</sub>-yielding section

10.5194/bg-2020-167 ◽

2020 ◽

Author(s):

Rafael Rasse ◽

Hervé Claustre ◽

Antoine Poteau

Keyword(s):

Microbial Communities ◽

Black Sea ◽

Denitrifying Bacteria ◽

The Black Sea ◽

Anammox Bacteria ◽

Published Data ◽

Strong Correlations ◽

Particle Layer ◽

Subsurface Waters ◽

Particle Backscattering

Abstract. Upper suboxic water masses confine a majority of the microbial communities that can produce up to 90 % of oceanic N2. This effective N2-yielding section encloses a suspended small-particle layer, inferred from particle backscattering (bbp) measurements. It is thus hypothesized that this layer (hereafter, the bbp-layer) is linked to N2-yielding microbial communities such as anammox and denitrifying bacteria – a hypothesis yet to be evaluated. Here, data collected by three BGC-Argo floats deployed in the Black Sea are used to investigate the origin of this bbp-layer. To this end, we evaluate how key drivers of anammox-denitrifying bacteria dynamics impact on the vertical distribution of bbp and the thickness of the bbp-layer. In conjunction with published data on N2 excess, our results suggest that the bbp-layer is at least partially composed of anammox-denitrifying bacteria for three main reasons: (1) strong correlations are recorded between bbp and nitrate; (2) the top location of the bbp-layer is driven by the ventilation of oxygen-rich subsurface waters, while its thickness is modulated by the amount of nitrate available to produce N2; (3) the maxima of both bbp and N2 excess coincide at the same isopycnals where denitrifying-anammox bacteria coexist. We thus advance that bbp and O2 can be exploited as a combined proxy to delineate the N2-yielding section of the Black Sea. This proxy can potentially contribute to refining delineation of the effective N2-yielding section of oxygen-deficient zones via data from the growing BGC-Argo float network.

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