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Nair GR, Kooverjee BB, de Scally S, Cowan DA, Makhalanyane TP. Changes in nutrient availability substantially alter bacteria and extracellular enzymatic activities in Antarctic soils. FEMS Microbiol Ecol 2024; 100:fiae071. [PMID: 38697936 PMCID: PMC11107947 DOI: 10.1093/femsec/fiae071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 03/07/2024] [Accepted: 05/01/2024] [Indexed: 05/05/2024] Open
Abstract
In polar regions, global warming has accelerated the melting of glacial and buried ice, resulting in meltwater run-off and the mobilization of surface nutrients. Yet, the short-term effects of altered nutrient regimes on the diversity and function of soil microbiota in polyextreme environments such as Antarctica, remains poorly understood. We studied these effects by constructing soil microcosms simulating augmented carbon, nitrogen, and moisture. Addition of nitrogen significantly decreased the diversity of Antarctic soil microbial assemblages, compared with other treatments. Other treatments led to a shift in the relative abundances of these microbial assemblages although the distributional patterns were random. Only nitrogen treatment appeared to lead to distinct community structural patterns, with increases in abundance of Proteobacteria (Gammaproteobateria) and a decrease in Verrucomicrobiota (Chlamydiae and Verrucomicrobiae).The effects of extracellular enzyme activities and soil parameters on changes in microbial taxa were also significant following nitrogen addition. Structural equation modeling revealed that nutrient source and extracellular enzyme activities were positive predictors of microbial diversity. Our study highlights the effect of nitrogen addition on Antarctic soil microorganisms, supporting evidence of microbial resilience to nutrient increases. In contrast with studies suggesting that these communities may be resistant to change, Antarctic soil microbiota responded rapidly to augmented nutrient regimes.
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Affiliation(s)
- Girish R Nair
- Department of Microbiology, Faculty of Science, Stellenbosch University, Stellenbosch 7600, South Africa
- Centre for Epidemic Response and Innovation, School for Data Science and Computational Thinking, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Bhaveni B Kooverjee
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Storme de Scally
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Thulani P Makhalanyane
- Department of Microbiology, Faculty of Science, Stellenbosch University, Stellenbosch 7600, South Africa
- Centre for Epidemic Response and Innovation, School for Data Science and Computational Thinking, Stellenbosch University, Stellenbosch 7600, South Africa
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Melekhina EN, Belykh ES, Kanev VA, Taskaeva AA, Tarabukin DV, Zinovyeva AN, Velegzhaninov IO, Rasova EE, Baturina OA, Kabilov MR, Markarova MY. Soil Microbiome in Conditions of Oil Pollution of Subarctic Ecosystems. Microorganisms 2023; 12:80. [PMID: 38257907 PMCID: PMC10820038 DOI: 10.3390/microorganisms12010080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/25/2023] [Accepted: 12/27/2023] [Indexed: 01/24/2024] Open
Abstract
The present study aimed to investigate the recovery of soil quality and the bacterial and fungal communities following various recultivation methods in areas contaminated with oil. Oil spills are known to have severe impacts on ecosystems; thus, the restoration of contaminated soils has become a significant challenge nowadays. The study was conducted in the forest-tundra zone of the European North-East, where 39 soil samples from five oil-contaminated sites and reference sites were subjected to metagenomic analyses. The contaminated sites were treated with different biopreparations, and the recovery of soil quality and microbial communities were analyzed. The analysis of bacteria and fungi communities was carried out using 16S rDNA and ITS metabarcoding. It was found that 68% of bacterial OTUs and 64% of fungal OTUs were unique to the reference plot and not registered in any of the recultivated plots. However, the species diversity of recultivated sites was similar, with 50-80% of bacterial OTUs and 44-60% of fungal OTUs being common to all sites. New data obtained through soil metabarcoding confirm our earlier conclusions about the effectiveness of using biopreparations with indigenous oil-oxidizing micro-organisms also with mineral fertilizers, and herbaceous plant seeds for soil remediation. It is possible that the characteristics of microbial communities will be informative in the bioindication of soils reclaimed after oil pollution.
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Affiliation(s)
- Elena N. Melekhina
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
| | - Elena S. Belykh
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
| | - Vladimir A. Kanev
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
| | - Anastasia A. Taskaeva
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
| | - Dmitry V. Tarabukin
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
| | - Aurika N. Zinovyeva
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
| | - Ilya O. Velegzhaninov
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
| | - Elena E. Rasova
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
| | - Olga A. Baturina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences (ICBFM SB RAS), Lavrentieva 8, 630090 Novosibirsk, Russia; (O.A.B.); (M.R.K.)
| | - Marsel R. Kabilov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences (ICBFM SB RAS), Lavrentieva 8, 630090 Novosibirsk, Russia; (O.A.B.); (M.R.K.)
| | - Maria Yu. Markarova
- Institute of Biology, Komi Scientifc Center, Ural Branch of Russian Academy of Sciences (IB FRC Komi SC UB RAS), Kommunisticheskaya 28, 167982 Syktyvkar, Russia; (E.S.B.); (V.A.K.); (A.A.T.); (D.V.T.); (A.N.Z.); (I.O.V.); (E.E.R.); (M.Y.M.)
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3
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Radziemska M, Gusiatin MZ, Cydzik-Kwiatkowska A, Blazejczyk A, Majewski G, Jaskulska I, Brtnicky M. Effect of freeze-thaw manipulation on phytostabilization of industrially contaminated soil with halloysite nanotubes. Sci Rep 2023; 13:22175. [PMID: 38092858 PMCID: PMC10719333 DOI: 10.1038/s41598-023-49698-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 12/11/2023] [Indexed: 12/17/2023] Open
Abstract
The latest trends in improving the performance properties of soils contaminated with potentially toxic elements (PTEs) relate to the possibility of using raw additives, including halloysite nanotubes (HNTs) due to eco-friendliness, and inexpensiveness. Lolium perenne L. was cultivated for 52 days in a greenhouse and then moved to a freezing-thawing chamber for 64 days. HNT addition into PTE-contaminated soil cultivated with grass under freezing-thawing conditions (FTC) was tested to demonstrate PTE immobilization during phytostabilization. The relative yields increased by 47% in HNT-enriched soil in a greenhouse, while under FTC decreased by 17% compared to the adequate greenhouse series. The higher PTE accumulation in roots in HNT presence was evident both in greenhouse and chamber conditions. (Cr/Cd and Cu)-relative contents were reduced in soil HNT-enriched-not-FTC-exposed, while (Cr and Cu) in HNT-enriched-FTC-exposed. PTE-immobilization was discernible by (Cd/Cr/Pb and Zn)-redistribution into the reducible fraction and (Cu/Ni and Zn) into the residual fraction in soil HNT-enriched-not-FTC-exposed. FTC and HNT facilitated transformation to the residual fraction mainly for Pb. Based on PTE-distribution patterns and redistribution indexes, HNT's role in increasing PTE stability in soils not-FTC-exposed is more pronounced than in FTC-exposed compared to the adequate series. Sphingomonas, Acidobacterium, and Mycobacterium appeared in all soils. HNTs mitigated FTC's negative effect on microbial diversity and increased Planctomycetia abundance.
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Affiliation(s)
- Maja Radziemska
- Institute of Environmental Engineering, Warsaw University of Life Sciences, 02-776, Warsaw, Poland.
| | - Mariusz Z Gusiatin
- Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, 10-719, Olsztyn, Poland
| | | | - Aurelia Blazejczyk
- Institute of Civil Engineering, Warsaw University of Life Sciences, 02-776, Warsaw, Poland
| | - Grzegorz Majewski
- Institute of Environmental Engineering, Warsaw University of Life Sciences, 02-776, Warsaw, Poland
| | - Iwona Jaskulska
- Faculty of Agriculture and Biotechnology, Bydgoszcz University of Science and Technology, 85-796, Bydgoszcz, Poland
| | - Martin Brtnicky
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Mendel University in Brno, 613 00, Brno, Czech Republic
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4
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Radziemska M, Gusiatin MZ, Cydzik-Kwiatkowska A, Blazejczyk A, Holatko J, Brtnicky M. Does biochar in combination with compost effectively promote phytostabilization of heavy metals in soil under different temperature regimes? THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 882:163634. [PMID: 37088391 DOI: 10.1016/j.scitotenv.2023.163634] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/15/2023] [Accepted: 04/17/2023] [Indexed: 05/03/2023]
Abstract
The article presents the effect of a combined amendment, i.e., biochar+compost (BC), on the process of Cd, Cu, Ni, Pb and Zn immobilization in soil cultivated with L. perenne under freezing and thawing conditions (FTC). In particular, the speciation analysis of the examined elements in phytostabilized soils based on their response using the sequential extraction, and the variability of the soil microbiome using 16S rRNA gene amplicon sequencing were systematically assessed. Metal stability in soils was evaluated by the reduced distribution index (Ir). Plants were grown in pots for 52 days under greenhouse conditions. After termination, phytostabilization was continued in a temperature chamber for 64 days to provide FTC. As a result, it was noted that biomass yield of L. perenne was promoted by BC (39 % higher than in the control pots) and reduced by FTC (45 % lower than in the BC-enriched soil not exposed to FTC). An efficacious level of phytostabilization, i.e., higher content of heavy metals in plant roots, was found in the BC-enriched soil, regardless of the changes in soil temperature conditions. BC improved soil pH before applying FTC more than after applying FTC. BC had the greatest impact on increasing Cu stability by redistributing it from the F1 and F2 fractions to the F3 and F4 fractions. For most metals, phytostabilization under FTC resulted in an increase in the proportion of the F1 fraction and a decrease in its stability. Only for Pb and Zn, FTC had greater impact on their stability than BC addition. In all soil samples, the core genera with about 2-3 % abundances were Sphingomonas sp. and Mycobacterium sp. FTC favored the growth of Bacteroidetes and Proteobacteria in soil. Microbial taxa that coped well with FTC but only in the absence of BC were Rhodococcus, Alkanindiges sp., Flavobacterium sp., Williamsia sp. Thermomonas sp.
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Affiliation(s)
- Maja Radziemska
- Institute of Environmental Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland.
| | - Mariusz Z Gusiatin
- Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-719 Olsztyn, Poland
| | - Agnieszka Cydzik-Kwiatkowska
- Institute of Environmental Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland
| | - Aurelia Blazejczyk
- Institute of Civil Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland
| | - Jiri Holatko
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 61300 Brno, Czech Republic; Agrovyzkum Rapotin, Ltd., Vyzkumniku 267, 788 13 Rapotin, Czech Republic
| | - Martin Brtnicky
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 61300 Brno, Czech Republic
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Cao X, Liu H, Liu Y, Jing J, Wen L, Xu Z, Liu X, Liu D, Zhuo Y, Wang L. N 2O emission associated with shifts of bacterial communities in riparian wetland during the spring thawing periods. Ecol Evol 2023; 13:e9888. [PMID: 36911318 PMCID: PMC9994613 DOI: 10.1002/ece3.9888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 02/19/2023] [Accepted: 02/21/2023] [Indexed: 03/14/2023] Open
Abstract
Soil freeze-thaw processes lead to high nitrous oxide (N2O) emissions and exacerbate the greenhouse effect. The wetlands of the Inner Mongolia Plateau are in the pronounced seasonal freeze-thaw zone, but the effect of spring thaw on N2O emissions and related microbial mechanisms is still unclear. We investigated the effects of different periods (freeze, freeze-thaw, and thaw) on soil bacterial community diversity and composition and greenhouse gas emissions during the spring freeze-thaw in the XiLin River riparian wetlands in China by amplicon sequencing and static dark box methods. The results showed that the freeze-thaw periods predominantly impact on the diversity and composition of the bacterial communities. The phyla composition of the soil bacteria communities of the three periods is similar in level, with Proteobacteria, Chloroflexi, Actinobacteria, and Acidobacteria dominating the microbial communities. The alpha-diversity of bacterial communities in different periods varies that the freezing period is higher than that of the freeze-thaw period (p < .05). Soil total carbon, soil water content, and microbial biomass carbon were the primary factors regulating the abundance and compositions of the bacterial communities during spring thawing periods. Based on functional predictions, the relative abundance of nitrification and denitrification genes was higher in the freezing period than in the thawing period, while the abundance was lowest in the freeze-thawing period. The correlation results found that N2O emissions were significantly correlated with amoA and amoB in nitrification genes, indicating that nitrification may be the main process of N2O production during spring thaw. This study reveals potential microbial mechanisms of N2O emission during spring thaw and provides data support and theoretical basis for further insight into the mechanism of N2O emission during spring thaw.
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Affiliation(s)
- Xiaoai Cao
- College of Ecology and Environment Inner Mongolia University Hohhot China
| | - Huamin Liu
- College of Ecology and Environment Inner Mongolia University Hohhot China.,Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station China Institute of Water Resources and Hydropower Research Beijing China
| | - Yang Liu
- Bayannur Sub-station, Inner Mongolia Environmental Monitoring Station Bayannur China
| | - Jin Jing
- Bayannur Sub-station, Inner Mongolia Environmental Monitoring Station Bayannur China
| | - Lu Wen
- College of Ecology and Environment Inner Mongolia University Hohhot China.,Collaborative Innovation Center for Grassland Ecological Security (Jointly Supported by the Ministry of Education of China and Inner Mongolia Autonomous Region) Hohhot China.,Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau Hohhot China
| | - Zhichao Xu
- College of Ecology and Environment Inner Mongolia University Hohhot China
| | - Xuhua Liu
- College of Ecology and Environment Inner Mongolia University Hohhot China
| | - Dongwei Liu
- College of Ecology and Environment Inner Mongolia University Hohhot China.,Collaborative Innovation Center for Grassland Ecological Security (Jointly Supported by the Ministry of Education of China and Inner Mongolia Autonomous Region) Hohhot China.,Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau Hohhot China
| | - Yi Zhuo
- College of Ecology and Environment Inner Mongolia University Hohhot China.,Collaborative Innovation Center for Grassland Ecological Security (Jointly Supported by the Ministry of Education of China and Inner Mongolia Autonomous Region) Hohhot China.,Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau Hohhot China
| | - Lixin Wang
- College of Ecology and Environment Inner Mongolia University Hohhot China.,Collaborative Innovation Center for Grassland Ecological Security (Jointly Supported by the Ministry of Education of China and Inner Mongolia Autonomous Region) Hohhot China.,Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau Hohhot China
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Carbon Emission and Biodiversity of Arctic Soil Microbial Communities of the Novaya Zemlya and Franz Josef Land Archipelagos. Microorganisms 2023; 11:microorganisms11020482. [PMID: 36838447 PMCID: PMC9962458 DOI: 10.3390/microorganisms11020482] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/06/2023] [Accepted: 02/09/2023] [Indexed: 02/17/2023] Open
Abstract
Cryogenic soils are the most important terrestrial carbon reservoir on the planet. However, the relationship between soil microbial diversity and CO2 emission by cryogenic soils is poorly studied. This is especially important in the context of rising temperatures in the high Arctic which can lead to the activation of microbial processes in soils and an increase in carbon input from cryogenic soils into the atmosphere. Here, using high-throughput sequencing of 16S rRNA gene amplicons, we analyzed microbial community composition and diversity metrics in relation to soil carbon dioxide emission, water-extractable organic carbon and microbial biomass carbon in the soils of the Barents Sea archipelagos, Novaya Zemlya and Franz Josef Land. It was found that the highest diversity and CO2 emission were observed on the Hooker and Heiss Islands of the Franz Josef Land archipelago, while the diversity and CO2 emission levels were lower on Novaya Zemlya. Soil moisture and temperature were the main parameters influencing the composition of soil microbial communities on both archipelagos. The data obtained show that CO2 emission levels and community diversity on the studied islands are influenced mostly by a number of local factors, such as soil moisture, microclimatic conditions, different patterns of vegetation and fecal input from animals such as reindeer.
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Radziemska M, Gusiatin MZ, Cydzik-Kwiatkowska A, Majewski G, Blazejczyk A, Brtnicky M. New approach strategy for heavy metals immobilization and microbiome structure long-term industrially contaminated soils. CHEMOSPHERE 2022; 308:136332. [PMID: 36088975 DOI: 10.1016/j.chemosphere.2022.136332] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/25/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
The progress of engineering technologies highly influences the development of methods that lead to the condition improvement of areas contaminated with heavy metals (HMs). The aided phytostabilization fits into this trend, and was used to evaluate HM-immobilization effectiveness in phytostabilized soils under variable temperatures by applying 16 freezing-thawing cycles (FTC). Diatomite amendment and Lolium perenne L., also were applied. Cd/Ni/Cu/Pb/Zn each total content in phytostabilized soils were determined, along with the verification for each metal of its distribution in four extracted fractions (F1 ÷ F4) from soils. Based on changes in HM distribution, each metal's stability was estimated. Moreover, HM accumulation in plant roots and stems and soil microbial composition were investigated. Independently of the experimental variant (no-FTC-exposure or FTC-exposure), the above-ground biomass yields in the diatomite-amended series were higher as compared to the corresponding control series. The evident changes in Pb/Zn-bioavailability were observed. The metal stability increase was mainly attributed to metal concentration decreasing in the F1 fraction and increasing in the F4 fraction, respectively. Diatomite increased Cd/Zn-stability in not-FTC-exposed-phytostabilized soils. FTC-exposure favorably influenced Pb/Zn stability. Diatomite increased soil pH values and Cd/Ni/Cu/Zn-bioaccumulation (except Pb) in roots than in stems (in both experimental variants). FTC-exposure influenced soil microbial composition, increasing bacteria abundance belonging to Actinobacteria, Gammaproteobacteria, and Sphingobacteria. At the genus level, FTC exposure significantly increased the abundances of Limnobacter sp., Tetrasphaera sp., Flavobacterium sp., and Dyella sp. Independently of the experimental variant, Sphingomonas sp. and Mycobacterium sp., which have a tolerance to HM contamination, were core bacterial groups, comprising about 6 ÷ 7% of all soil bacteria.
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Affiliation(s)
- Maja Radziemska
- Institute of Environmental Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776, Warsaw, Poland.
| | - Mariusz Z Gusiatin
- Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-719, Olsztyn, Poland
| | - Agnieszka Cydzik-Kwiatkowska
- Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-719, Olsztyn, Poland
| | - Grzegorz Majewski
- Institute of Environmental Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776, Warsaw, Poland
| | - Aurelia Blazejczyk
- Institute of Civil Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776, Warsaw, Poland
| | - Martin Brtnicky
- Institute of Chemistry and Technology of Environmental Protection, Faculty of Chemistry, Brno University of Technology, Purkyňova 118, 612 00, Brno, Czech Republic; Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, 613 00, Brno, Czech Republic
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Pessi IS, Viitamäki S, Virkkala AM, Eronen-Rasimus E, Delmont TO, Marushchak ME, Luoto M, Hultman J. In-depth characterization of denitrifier communities across different soil ecosystems in the tundra. ENVIRONMENTAL MICROBIOME 2022; 17:30. [PMID: 35690846 PMCID: PMC9188126 DOI: 10.1186/s40793-022-00424-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 06/03/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND In contrast to earlier assumptions, there is now mounting evidence for the role of tundra soils as important sources of the greenhouse gas nitrous oxide (N2O). However, the microorganisms involved in the cycling of N2O in this system remain largely uncharacterized. Since tundra soils are variable sources and sinks of N2O, we aimed at investigating differences in community structure across different soil ecosystems in the tundra. RESULTS We analysed 1.4 Tb of metagenomic data from soils in northern Finland covering a range of ecosystems from dry upland soils to water-logged fens and obtained 796 manually binned and curated metagenome-assembled genomes (MAGs). We then searched for MAGs harbouring genes involved in denitrification, an important process driving N2O emissions. Communities of potential denitrifiers were dominated by microorganisms with truncated denitrification pathways (i.e., lacking one or more denitrification genes) and differed across soil ecosystems. Upland soils showed a strong N2O sink potential and were dominated by members of the Alphaproteobacteria such as Bradyrhizobium and Reyranella. Fens, which had in general net-zero N2O fluxes, had a high abundance of poorly characterized taxa affiliated with the Chloroflexota lineage Ellin6529 and the Acidobacteriota subdivision Gp23. CONCLUSIONS By coupling an in-depth characterization of microbial communities with in situ measurements of N2O fluxes, our results suggest that the observed spatial patterns of N2O fluxes in the tundra are related to differences in the composition of denitrifier communities.
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Affiliation(s)
- Igor S. Pessi
- Department of Microbiology, University of Helsinki, Viikinkaari 9, 00014 Helsinki, Finland
- Helsinki Institute of Sustainability Science (HELSUS), Yliopistonkatu 3, 00014 Helsinki, Finland
| | - Sirja Viitamäki
- Department of Microbiology, University of Helsinki, Viikinkaari 9, 00014 Helsinki, Finland
| | - Anna-Maria Virkkala
- Woodwell Climate Research Center, 149 Woods Hole Road, Falmouth, MA 02540-1644 USA
- Department of Geosciences and Geography, University of Helsinki, Gustaf Hällströmin katu 2, 00014 Helsinki, Finland
| | - Eeva Eronen-Rasimus
- Department of Microbiology, University of Helsinki, Viikinkaari 9, 00014 Helsinki, Finland
- Marine Research Centre, Finnish Environment Institute (SYKE), Agnes Sjöbergin katu 2, 00790 Helsinki, Finland
| | - Tom O. Delmont
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Université d’Evry, Université Paris-Saclay, 91057 Evry, France
| | - Maija E. Marushchak
- Department of Biological and Environmental Science, University of Jyväskylä, 40014 Jyväskylä, Finland
- Department of Environmental and Biological Sciences, University of Eastern Finland, 70211 Kuopio, Finland
| | - Miska Luoto
- Department of Geosciences and Geography, University of Helsinki, Gustaf Hällströmin katu 2, 00014 Helsinki, Finland
| | - Jenni Hultman
- Department of Microbiology, University of Helsinki, Viikinkaari 9, 00014 Helsinki, Finland
- Helsinki Institute of Sustainability Science (HELSUS), Yliopistonkatu 3, 00014 Helsinki, Finland
- Natural Resources Institute Finland (LUKE), Latokartanonkaari 9, 00790 Helsinki, Finland
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Radziemska M, Gusiatin MZ, Cydzik-Kwiatkowska A, Blazejczyk A, Kumar V, Kintl A, Brtnicky M. Effect of Biochar on Metal Distribution and Microbiome Dynamic of a Phytostabilized Metalloid-Contaminated Soil Following Freeze-Thaw Cycles. MATERIALS 2022; 15:ma15113801. [PMID: 35683097 PMCID: PMC9181493 DOI: 10.3390/ma15113801] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/18/2022] [Accepted: 05/23/2022] [Indexed: 02/04/2023]
Abstract
In the present paper the effectiveness of biochar-aided phytostabilization of metal/metalloid-contaminated soil under freezing-thawing conditions and using the metal tolerating test plant Lolium perenne L. is comprehensively studied. The vegetative experiment consisted of plants cultivated for over 52 days with no exposure to freezing-thawing in a glass greenhouse, followed by 64 days under freezing-thawing in a temperature-controlled apparatus and was carried out in initial soil derived from a post-industrial urban area, characterized by the higher total content of Zn, Pb, Cu, Cr, As and Hg than the limit values included in the classification provided by the Regulation of the Polish Ministry of Environment. According to the substance priority list published by the Toxic Substances and Disease Registry Agency, As, Pb, and Hg are also indicated as being among the top three most hazardous substances. The initial soil was modified by biochar obtained from willow chips. The freeze-thaw effect on the total content of metals/metalloids (metal(-loid)s) in plant materials (roots and above-ground parts) and in phytostabilized soils (non- and biochar-amended) as well as on metal(-loid) concentration distribution/redistribution between four BCR (community bureau of reference) fractions extracted from phytostabilized soils was determined. Based on metal(-loid)s redistribution in phytostabilized soils, their stability was evaluated using the reduced partition index (Ir). Special attention was paid to investigating soil microbial composition. In both cases, before and after freezing-thawing, biochar increased plant biomass, soil pH value, and metal(-loid)s accumulation in roots, and decreased metal(-loid)s accumulation in stems and total content in the soil, respectively, as compared to the corresponding non-amended series (before and after freezing-thawing, respectively). In particular, in the phytostabilized biochar-amended series after freezing-thawing, the recorded total content of Zn, Cu, Pb, and As in roots substantially increased as well as the Hg, Cu, Cr, and Zn in the soil was significantly reduced as compared to the corresponding non-amended series after freezing-thawing. Moreover, exposure to freezing-thawing itself caused redistribution of examined metal(-loid)s from mobile and/or potentially mobile into the most stable fraction, but this transformation was favored by biochar presence, especially for Cu, Pb, Cr, and Hg. While freezing-thawing greatly affected soil microbiome composition, biochar reduced the freeze-thaw adverse effect on bacterial diversity and helped preserve bacterial groups important for efficient soil nutrient conversion. In biochar-amended soil exposed to freezing-thawing, psychrotolerant and trace element-resistant genera such as Rhodococcus sp. or Williamsia sp. were most abundant.
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Affiliation(s)
- Maja Radziemska
- Institute of Environmental Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland
- Correspondence: ; Tel.: +48-22-593-5307
| | - Mariusz Z. Gusiatin
- Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-719 Olsztyn, Poland; (M.Z.G.); (A.C.-K.)
| | - Agnieszka Cydzik-Kwiatkowska
- Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-719 Olsztyn, Poland; (M.Z.G.); (A.C.-K.)
| | - Aurelia Blazejczyk
- Institute of Civil Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland;
| | - Vinod Kumar
- Department of Botany, Government Degree College, Ramban 182144, India;
| | - Antonin Kintl
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 61300 Brno, Czech Republic; (A.K.); (M.B.)
- Agricultural Research, Ltd., Zahradni 400/1, 66441 Troubsko, Czech Republic
| | - Martin Brtnicky
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 61300 Brno, Czech Republic; (A.K.); (M.B.)
- Institute of Chemistry and Technology of Environmental Protection, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 61200 Brno, Czech Republic
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10
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Minnebo Y, De Paepe K, Raes J, Van de Wiele T. Nutrient load acts as a driver of gut microbiota load, community composition and metabolic functionality in the simulator of the human intestinal microbial ecosystem. FEMS Microbiol Ecol 2021; 97:6329685. [PMID: 34320208 DOI: 10.1093/femsec/fiab111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 07/26/2021] [Indexed: 11/13/2022] Open
Abstract
A recently introduced quantitative framework for gut microbiota analysis indicated that microbial load alterations can be linked to various diseases, making it essential to pinpoint its determinants. We identified nutrient load as a main driver of the quantitative microbial community composition and functionality in vitro by stepwise decreasing standardised feed concentrations from 100% to 33, 20 and 10% in five-day intervals. While the proportional composition and metabolic profile were mainly determined by the inter-individual variability (35 and 41%), nutrient load accounted for 58%, 23% and 65% of the observed variation in the microbial load, quantitative composition and net daily metabolite production, respectively. After the tenfold nutrient reduction, the microbial load decreased by 79.72 ± 9% and 82.96 ± 1.66% in the proximal and distal colon, respectively, while the net total short-chain fatty acid production dropped by 79.42 ± 4.42% and 84.58 ± 2.42%, respectively. The majority of microbial taxa quantitatively decreased, whereas a select group of nutritional specialists, such as Akkermansia muciniphila and Bilophila wadsworthia and a number of opportunistic pathogens remained unaffected. This shows that nutrient load is an important driver of the human gut microbiome and should be considered in future in vitro and in vivo dietary research.
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Affiliation(s)
- Yorick Minnebo
- Center for Microbial Ecology and Technology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Kim De Paepe
- Center for Microbial Ecology and Technology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Jeroen Raes
- Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, KU Leuven, Herestraat 49, 3000 Leuven, Belgium.,Center for Microbiology, VIB, Herestraat 49, 3000 Leuven, Belgium
| | - Tom Van de Wiele
- Center for Microbial Ecology and Technology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
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11
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Rivera-Urbalejo AP, Vázquez D, Fernández Vázquez JL, Rosete Enríquez M, Cesa-Luna C, Morales-García YE, Muñoz Rojas J, Quintero Hernández V. APORTES Y DIFICULTADES DE LA METAGENÓMICA DE SUELOS Y SU IMPACTO EN LA AGRICULTURA. ACTA BIOLÓGICA COLOMBIANA 2021. [DOI: 10.15446/abc.v26n3.85760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Los microorganismos son de gran interés porque colonizan todo tipo de ambiente, sin embargo, uno de los problemas al que nos enfrentamos para conocer su diversidad biológica es que no todos los microorganismos son cultivables. El desarrollo de nuevas tecnologías como la generación de vectores de clonación aunado al desarrollo de técnicas de secuenciación de alto rendimiento ha favorecido el surgimiento de una nueva herramienta llamada metagenómica, la cual nos permite estudiar genomas de comunidades enteras de microorganismos. Debido a que ningún ambiente es idéntico a otro, es importante mencionar que dependiendo del tipo de muestra a analizar será el tipo de reto al cual nos enfrentaremos al trabajar con metagenómica, en el caso específico del suelo existen diversas variantes como la contaminación del suelo con metales pesados o diversos compuestos químicos que podrían limitar los estudios. Sin embargo, pese a las limitaciones que el mismo ambiente presenta, la metagenómica ha permitido tanto el descubrimiento de nuevos genes como la caracterización de las comunidades microbianas que influyen positivamente en el desarrollo de plantas, lo cual en un futuro podría generar un gran impacto en la agricultura. En este artículo se realizó una revisión de diversas investigaciones que han empleado metagenómica, reportadas en las bases de datos de PudMed y Google Schoolar, con el objetivo de examinar los beneficios y limitaciones de las diversas metodologías empleadas en el tratamiento del ADN metagenómico de suelo y el impacto de la metagenómica en la agricultura.
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12
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Coyne KJ, Parker AE, Lee CK, Sohm JA, Kalmbach A, Gunderson T, León-Zayas R, Capone DG, Carpenter EJ, Cary SC. The distribution and relative ecological roles of autotrophic and heterotrophic diazotrophs in the McMurdo Dry Valleys, Antarctica. FEMS Microbiol Ecol 2020; 96:5714082. [PMID: 31967635 PMCID: PMC7043275 DOI: 10.1093/femsec/fiaa010] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Accepted: 01/21/2020] [Indexed: 12/13/2022] Open
Abstract
The McMurdo Dry Valleys (MDV) in Antarctica harbor a diverse assemblage of mat-forming diazotrophic cyanobacteria that play a key role in nitrogen cycling. Prior research showed that heterotrophic diazotrophs also make a substantial contribution to nitrogen fixation in MDV. The goals of this study were to survey autotrophic and heterotrophic diazotrophs across the MDV to investigate factors that regulate the distribution and relative ecological roles of each group. Results indicated that diazotrophs were present only in samples with mats, suggesting a metabolic coupling between autotrophic and heterotrophic diazotrophs. Analysis of 16S rRNA and nifH gene sequences also showed that diazotrophs were significantly correlated to the broader bacterial community, while co-occurrence network analysis revealed potential interspecific interactions. Consistent with previous studies, heterotrophic diazotrophs in MDV were diverse, but largely limited to lakes and their outlet streams, or other environments protected from desiccation. Despite the limited distribution, heterotrophic diazotrophs may make a substantial contribution to the nitrogen budget of MDV due to larger surface area and longer residence times of lakes. This work contributes to our understanding of key drivers of bacterial community structure in polar deserts and informs future efforts to investigate the contribution of nitrogen fixation to MDV ecosystems.
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Affiliation(s)
- Kathryn J Coyne
- College of Earth, Ocean, and Environment, University of Delaware, Lewes, DE 19958, USA
| | - Alexander E Parker
- Estuary and Ocean Science Center, San Francisco State University, Tiburon, CA 94920, USA
| | - Charles K Lee
- International Centre for Terrestrial Antarctic Research, School of Science, University of Waikato, Hamilton 3240, New Zealand
| | - Jill A Sohm
- Wrigley Institute for Environmental Studies and Department of Biological Sciences, University of Southern California, Los Angeles, CA 9008-037, USA
| | - Andrew Kalmbach
- Estuary and Ocean Science Center, San Francisco State University, Tiburon, CA 94920, USA
| | - Troy Gunderson
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 9008-037, USA
| | - Rosa León-Zayas
- Willamette University, Biology Department, Salem, OR 97301, USA
| | - Douglas G Capone
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 9008-037, USA
| | - Edward J Carpenter
- Estuary and Ocean Science Center, San Francisco State University, Tiburon, CA 94920, USA
| | - S Craig Cary
- College of Earth, Ocean, and Environment, University of Delaware, Lewes, DE 19958, USA.,International Centre for Terrestrial Antarctic Research, School of Science, University of Waikato, Hamilton 3240, New Zealand
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13
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Bezuidt OKI, Lebre PH, Pierneef R, León-Sobrino C, Adriaenssens EM, Cowan DA, Van de Peer Y, Makhalanyane TP. Phages Actively Challenge Niche Communities in Antarctic Soils. mSystems 2020; 5:e00234-20. [PMID: 32371471 PMCID: PMC7205518 DOI: 10.1128/msystems.00234-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 04/06/2020] [Indexed: 12/22/2022] Open
Abstract
By modulating the structure, diversity, and trophic outputs of microbial communities, phages play crucial roles in many biomes. In oligotrophic polar deserts, the effects of katabatic winds, constrained nutrients, and low water availability are known to limit microbial activity. Although phages may substantially govern trophic interactions in cold deserts, relatively little is known regarding the precise ecological mechanisms. Here, we provide the first evidence of widespread antiphage innate immunity in Antarctic environments using metagenomic sequence data from hypolith communities as model systems. In particular, immunity systems such as DISARM and BREX are shown to be dominant systems in these communities. Additionally, we show a direct correlation between the CRISPR-Cas adaptive immunity and the metavirome of hypolith communities, suggesting the existence of dynamic host-phage interactions. In addition to providing the first exploration of immune systems in cold deserts, our results suggest that phages actively challenge niche communities in Antarctic polar deserts. We provide evidence suggesting that the regulatory role played by phages in this system is an important determinant of bacterial host interactions in this environment.IMPORTANCE In Antarctic environments, the combination of both abiotic and biotic stressors results in simple trophic levels dominated by microbiomes. Although the past two decades have revealed substantial insights regarding the diversity and structure of microbiomes, we lack mechanistic insights regarding community interactions and how phages may affect these. By providing the first evidence of widespread antiphage innate immunity, we shed light on phage-host dynamics in Antarctic niche communities. Our analyses reveal several antiphage defense systems, including DISARM and BREX, which appear to dominate in cold desert niche communities. In contrast, our analyses revealed that genes which encode antiphage adaptive immunity were underrepresented in these communities, suggesting lower infection frequencies in cold edaphic environments. We propose that by actively challenging niche communities, phages play crucial roles in the diversification of Antarctic communities.
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Affiliation(s)
- Oliver K I Bezuidt
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Pedro Humberto Lebre
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Rian Pierneef
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Biotechnology Platform, Agricultural Research Council, Pretoria, South Africa
| | - Carlos León-Sobrino
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | | | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Yves Van de Peer
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Thulani P Makhalanyane
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
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14
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Barnard S, Van Goethem MW, de Scally SZ, Cowan DA, van Rensburg PJ, Claassens S, Makhalanyane TP. Increased temperatures alter viable microbial biomass, ammonia oxidizing bacteria and extracellular enzymatic activities in Antarctic soils. FEMS Microbiol Ecol 2020; 96:5818763. [DOI: 10.1093/femsec/fiaa065] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 04/03/2020] [Indexed: 12/13/2022] Open
Abstract
ABSTRACT
The effects of temperature on microorganisms in high latitude regions, and their possible feedbacks in response to change, are unclear. Here, we assess microbial functionality and composition in response to a substantial temperature change. Total soil biomass, amoA gene sequencing, extracellular activity assays and soil physicochemistry were measured to assess a warming scenario. Soil warming to 15°C for 30 days triggered a significant decrease in microbial biomass compared to baseline soils (0°C; P < 0.05) after incubations had induced an initial increase. These changes coincided with increases in extracellular enzymatic activity for peptide hydrolysis and phenolic oxidation at higher temperatures, but not for the degradation of carbon substrates. Shifts in ammonia-oxidising bacteria (AOB) community composition related most significantly to changes in soil carbon content (P < 0.05), which gradually increased in microcosms exposed to a persistently elevated temperature relative to baseline incubations, while temperature did not influence AOBs. The concentration of soil ammonium (NH4+) decreased significantly at higher temperatures subsequent to an initial increase, possibly due to higher conversion rates of NH4+ to nitrate by nitrifying bacteria. We show that higher soil temperatures may reduce viable microbial biomass in cold environments but stimulate their activity over a short period.
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Affiliation(s)
- Sebastian Barnard
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, Natural Sciences 2 Building, University of Pretoria, Pretoria, 0028, South Africa
| | - Marc W Van Goethem
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, Natural Sciences 2 Building, University of Pretoria, Pretoria, 0028, South Africa
| | - Storme Z de Scally
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, Natural Sciences 2 Building, University of Pretoria, Pretoria, 0028, South Africa
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, Natural Sciences 2 Building, University of Pretoria, Pretoria, 0028, South Africa
| | - Peet Jansen van Rensburg
- Focus Area Human Metabolomics, North-West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom 2520, South Africa
| | - Sarina Claassens
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom 2520, South Africa
| | - Thulani P Makhalanyane
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, Natural Sciences 2 Building, University of Pretoria, Pretoria, 0028, South Africa
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15
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Millán-Aguiñaga N, Soldatou S, Brozio S, Munnoch JT, Howe J, Hoskisson PA, Duncan KR. Awakening ancient polar Actinobacteria: diversity, evolution and specialized metabolite potential. MICROBIOLOGY-SGM 2020; 165:1169-1180. [PMID: 31592756 DOI: 10.1099/mic.0.000845] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Polar and subpolar ecosystems are highly vulnerable to global climate change with consequences for biodiversity and community composition. Bacteria are directly impacted by future environmental change and it is therefore essential to have a better understanding of microbial communities in fluctuating ecosystems. Exploration of Polar environments, specifically sediments, represents an exciting opportunity to uncover bacterial and chemical diversity and link this to ecosystem and evolutionary parameters. In terms of specialized metabolite production, the bacterial order Actinomycetales, within the phylum Actinobacteria are unsurpassed, producing 10 000 specialized metabolites accounting for over 45 % of all bioactive microbial metabolites. A selective isolation approach focused on spore-forming Actinobacteria of 12 sediment cores from the Antarctic and sub-Arctic generated a culture collection of 50 strains. This consisted of 39 strains belonging to rare A ctinomycetales genera including Microbacterium, Rhodococcus and Pseudonocardia. This study used a combination of nanopore sequencing and molecular networking to explore the community composition, culturable bacterial diversity, evolutionary relatedness and specialized metabolite potential of these strains. Metagenomic analyses using MinION sequencing was able to detect the phylum Actinobacteria across polar sediment cores at an average of 13 % of the total bacterial reads. The resulting molecular network consisted of 1652 parent ions and the lack of known metabolite identification supports the argument that Polar bacteria are likely to produce previously unreported chemistry.
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Affiliation(s)
- Natalie Millán-Aguiñaga
- Universidad Autónoma de Baja California, Facultad de Ciencias Marinas, Ensenada, Baja California, México
| | - Sylvia Soldatou
- University of Strathclyde, Strathclyde Institute of Pharmacy and Biomedical Science, Glasgow, UK
| | - Sarah Brozio
- University of Strathclyde, Strathclyde Institute of Pharmacy and Biomedical Science, Glasgow, UK
| | - John T Munnoch
- University of Strathclyde, Strathclyde Institute of Pharmacy and Biomedical Science, Glasgow, UK
| | - John Howe
- The Scottish Association for Marine Science, The Scottish Marine Institute, ObanArgyll, UK
| | - Paul A Hoskisson
- University of Strathclyde, Strathclyde Institute of Pharmacy and Biomedical Science, Glasgow, UK
| | - Katherine R Duncan
- University of Strathclyde, Strathclyde Institute of Pharmacy and Biomedical Science, Glasgow, UK
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16
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Sanders T, Fiencke C, Hüpeden J, Pfeiffer EM, Spieck E. Cold Adapted Nitrosospira sp.: A Potential Crucial Contributor of Ammonia Oxidation in Cryosols of Permafrost-Affected Landscapes in Northeast Siberia. Microorganisms 2019; 7:E699. [PMID: 31847402 PMCID: PMC6955795 DOI: 10.3390/microorganisms7120699] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 12/10/2019] [Accepted: 12/12/2019] [Indexed: 01/01/2023] Open
Abstract
Permafrost-affected landscape soils are rich in organic matter and contain a high fraction of organic nitrogen, but much of this organic matter remains inaccessible due to nitrogen limitation. Microbial nitrification is a key process in the nitrogen cycle, controlling the availability of dissolved inorganic nitrogen (DIN) such as ammonium and nitrate. In this study, we investigate the microbial diversity of canonical nitrifiers and their potential nitrifying activity in the active layer of different Arctic cryosols in the Lena River Delta in North-East Siberia. These cryosols are located on Samoylov Island, which has two geomorphological landscapes with mineral soils in the modern floodplain and organic-rich soils in the low-centered polygonal tundra of the Holocene river terrace. Microcosm incubations show that the highest potential ammonia oxidation rates are found in low organic soils, and the rates depend on organic matter content and quality, vegetation cover, and water content. As shown by 16S rRNA amplicon sequencing, nitrifiers represented 0.6% to 6.2% of the total microbial community. More than 50% of the nitrifiers belonged to the genus Nitrosospira. Based on PCR amoA analysis, ammonia-oxidizing bacteria (AOB) were found in nearly all soil types, whereas ammonia-oxidizing archaea (AOA) were only detected in low-organic soils. In cultivation-based approaches, mainly Nitrosospira-like AOB were enriched and characterized as psychrotolerant, with temperature optima slightly above 20 °C. This study suggests a ubiquitous distribution of ammonia-oxidizing microorganisms (bacteria and archaea) in permafrost-affected landscapes of Siberia with cold-adapted AOB, especially of the genus Nitrosospira, as potentially crucial ammonia oxidizers in the cryosols.
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Affiliation(s)
- Tina Sanders
- Helmholtz Zentrum Geesthacht, Institut für Küstenforschung, Max-Planck-Str. 1, 21502 Geesthacht, Germany
| | - Claudia Fiencke
- Universität Hamburg, Institut für Bodenkunde, Allende-Platz 2, 20146 Hamburg, Germany; (C.F.); (E.M.P.)
- Center for Earth System Research and Sustainability, Universität Hamburg, Allende-Platz 2, 20146 Hamburg, Germany
| | - Jennifer Hüpeden
- Universität Hamburg, Mikrobiologie und Biotechnologie, Ohnhorststr. 18, 22609 Hamburg, Germany; (J.H.); (E.S.)
| | - Eva Maria Pfeiffer
- Universität Hamburg, Institut für Bodenkunde, Allende-Platz 2, 20146 Hamburg, Germany; (C.F.); (E.M.P.)
- Center for Earth System Research and Sustainability, Universität Hamburg, Allende-Platz 2, 20146 Hamburg, Germany
| | - Eva Spieck
- Universität Hamburg, Mikrobiologie und Biotechnologie, Ohnhorststr. 18, 22609 Hamburg, Germany; (J.H.); (E.S.)
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17
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Oh HN, Park D, Seong HJ, Kim D, Sul WJ. Antarctic tundra soil metagenome as useful natural resources of cold-active lignocelluolytic enzymes. J Microbiol 2019; 57:865-873. [PMID: 31571125 DOI: 10.1007/s12275-019-9217-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/03/2019] [Accepted: 07/04/2019] [Indexed: 11/25/2022]
Abstract
Lignocellulose composed of complex carbohydrates and aromatic heteropolymers is one of the principal materials for the production of renewable biofuels. Lignocellulose-degrading genes from cold-adapted bacteria have a potential to increase the productivity of biological treatment of lignocellulose biomass by providing a broad range of treatment temperatures. Antarctic soil metagenomes allow to access novel genes encoding for the cold-active lignocellulose-degrading enzymes, for biotechnological and industrial applications. Here, we investigated the metagenome targeting cold-adapted microbes in Antarctic organic matter-rich soil (KS 2-1) to mine lignolytic and celluloytic enzymes by performing single molecule, real-time metagenomic (SMRT) sequencing. In the assembled Antarctic metagenomic contigs with relative long reads, we found that 162 (1.42%) of total 11,436 genes were annotated as carbohydrate-active enzymes (CAZy). Actinobacteria, the dominant phylum in this soil's metagenome, possessed most of candidates of lignocellulose catabolic genes like glycoside hydrolase families (GH13, GH26, and GH5) and auxiliary activity families (AA7 and AA3). The predicted lignocellulose degradation pathways in Antarctic soil metagenome showed synergistic role of various CAZyme harboring bacterial genera including Streptomyces, Streptosporangium, and Amycolatopsis. From phylogenetic relationships with cellular and environmental enzymes, several genes having potential for participating in overall lignocellulose degradation were also found. The results indicated the presence of lignocellulose-degrading bacteria in Antarctic tundra soil and the potential benefits of the lignocelluolytic enzymes as candidates for cold-active enzymes which will be used for the future biofuel-production industry.
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Affiliation(s)
- Han Na Oh
- Department of Systems Biotechnology, Chung-Ang University, Anseong, 17546, Republic of Korea
| | - Doyoung Park
- Department of Systems Biotechnology, Chung-Ang University, Anseong, 17546, Republic of Korea
| | - Hoon Je Seong
- Department of Systems Biotechnology, Chung-Ang University, Anseong, 17546, Republic of Korea
| | - Dockyu Kim
- Division of Polar Life Sciences, Korea Polar Research Institute, Incheon, 21990, Republic of Korea.
| | - Woo Jun Sul
- Department of Systems Biotechnology, Chung-Ang University, Anseong, 17546, Republic of Korea.
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18
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Zhelezova A, Chernov T, Tkhakakhova A, Xenofontova N, Semenov M, Kutovaya O. Prokaryotic community shifts during soil formation on sands in the tundra zone. PLoS One 2019; 14:e0206777. [PMID: 30939175 PMCID: PMC6445424 DOI: 10.1371/journal.pone.0206777] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 03/18/2019] [Indexed: 12/03/2022] Open
Abstract
A chronosequence approach, i.e., a comparison of spatially distinct plots with different stages of succession, is commonly used for studying microbial community dynamics during paedogenesis. The successional traits of prokaryotic communities following sand fixation processes have previously been characterized for arid and semi-arid regions, but they have not been considered for the tundra zone, where the environmental conditions are unfavourable for the establishment of complicated biocoenoses. In this research, we characterized the prokaryotic diversity and abundance of microbial genes found in a typical tundra and wooded tundra along a gradient of increasing vegetation—unfixed aeolian sand, semi-fixed surfaces with mosses and lichens, and mature soil under fully developed plant cover. Microbial communities from typical tundra and wooded tundra plots at three stages of sand fixation were compared using quantitative polymerase chain reaction (qPCR) and high-throughput sequencing of 16S rRNA gene libraries. The abundances of ribosomal genes increased gradually in both chronosequences, and a similar trend was observed for the functional genes related to the nitrogen cycle (nifH, bacterial amoA, nirK and nirS). The relative abundance of Planctomycetes increased, while those of Thaumarchaeota, Cyanobacteria and Chloroflexi decreased from unfixed sands to mature soils. According to β-diversity analysis, prokaryotic communities of unfixed sands were more heterogeneous compared to those of mature soils. Despite the differences in the plant cover of the two mature soils, the structural compositions of the prokaryotic communities were shaped in the same way. Thus, sand fixation in the tundra zone increases archaeal, bacterial and fungal abundances, shifts and unifies prokaryotic communities structure.
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Affiliation(s)
- Alena Zhelezova
- V.V. Dokuchaev Soil Science Institute, Department of Soil Biology and Biochemistry, Moscow, Russia
- * E-mail:
| | - Timofey Chernov
- V.V. Dokuchaev Soil Science Institute, Department of Soil Biology and Biochemistry, Moscow, Russia
| | - Azida Tkhakakhova
- V.V. Dokuchaev Soil Science Institute, Department of Soil Biology and Biochemistry, Moscow, Russia
| | - Natalya Xenofontova
- V.V. Dokuchaev Soil Science Institute, Department of Soil Biology and Biochemistry, Moscow, Russia
- Lomonosov Moscow State University, Department of Soil Science, Moscow, Russia
| | - Mikhail Semenov
- V.V. Dokuchaev Soil Science Institute, Department of Soil Biology and Biochemistry, Moscow, Russia
| | - Olga Kutovaya
- V.V. Dokuchaev Soil Science Institute, Department of Soil Biology and Biochemistry, Moscow, Russia
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Lambrechts S, Willems A, Tahon G. Uncovering the Uncultivated Majority in Antarctic Soils: Toward a Synergistic Approach. Front Microbiol 2019; 10:242. [PMID: 30828325 PMCID: PMC6385771 DOI: 10.3389/fmicb.2019.00242] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 01/29/2019] [Indexed: 01/22/2023] Open
Abstract
Although Antarctica was once believed to be a sterile environment, it is now clear that the microbial communities inhabiting the Antarctic continent are surprisingly diverse. Until the beginning of the new millennium, little was known about the most abundant inhabitants of the continent: prokaryotes. From then on, however, the rising use of deep sequencing techniques has led to a better understanding of the Antarctic prokaryote diversity and provided insights in the composition of prokaryotic communities in different Antarctic environments. Although these cultivation-independent approaches can produce millions of sequences, linking these data to organisms is hindered by several problems. The largest difficulty is the lack of biological information on large parts of the microbial tree of life, arising from the fact that most microbial diversity on Earth has never been characterized in laboratory cultures. These unknown prokaryotes, also known as microbial dark matter, have been dominantly detected in all major environments on our planet. Laboratory cultures provide access to the complete genome and the means to experimentally verify genomic predictions and metabolic functions and to provide evidence of horizontal gene transfer. Without such well-documented reference data, microbial dark matter will remain a major blind spot in deep sequencing studies. Here, we review our current understanding of prokaryotic communities in Antarctic ice-free soils based on cultivation-dependent and cultivation-independent approaches. We discuss advantages and disadvantages of both approaches and how these strategies may be combined synergistically to strengthen each other and allow a more profound understanding of prokaryotic life on the frozen continent.
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Affiliation(s)
- Sam Lambrechts
- Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | | | - Guillaume Tahon
- Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
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Rocca JD, Simonin M, Blaszczak JR, Ernakovich JG, Gibbons SM, Midani FS, Washburne AD. The Microbiome Stress Project: Toward a Global Meta-Analysis of Environmental Stressors and Their Effects on Microbial Communities. Front Microbiol 2019; 9:3272. [PMID: 30687263 PMCID: PMC6335337 DOI: 10.3389/fmicb.2018.03272] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 12/17/2018] [Indexed: 01/19/2023] Open
Abstract
Microbial community structure is highly sensitive to natural (e.g., drought, temperature, fire) and anthropogenic (e.g., heavy metal exposure, land-use change) stressors. However, despite an immense amount of data generated, systematic, cross-environment analyses of microbiome responses to multiple disturbances are lacking. Here, we present the Microbiome Stress Project, an open-access database of environmental and host-associated 16S rRNA amplicon sequencing studies collected to facilitate cross-study analyses of microbiome responses to stressors. This database will comprise published and unpublished datasets re-processed from the raw sequences into exact sequence variants using our standardized computational pipeline. Our database will provide insight into general response patterns of microbiome diversity, structure, and stability to environmental stressors. It will also enable the identification of cross-study associations between single or multiple stressors and specific microbial clades. Here, we present a proof-of-concept meta-analysis of 606 microbiomes (from nine studies) to assess microbial community responses to: (1) one stressor in one environment: soil warming across a variety of soil types, (2) a range of stressors in one environment: soil microbiome responses to a comprehensive set of stressors (incl. temperature, diesel, antibiotics, land use change, drought, and heavy metals), (3) one stressor across a range of environments: copper exposure effects on soil, sediment, activated-sludge reactors, and gut environments, and (4) the general trends of microbiome stressor responses. Overall, we found that stressor exposure significantly decreases microbiome alpha diversity and increases beta diversity (community dispersion) across a range of environments and stressor types. We observed a hump-shaped relationship between microbial community resistance to stressors (i.e., the average pairwise similarity score between the control and stressed communities) and alpha diversity. We used Phylofactor to identify microbial clades and individual taxa as potential bioindicators of copper contamination across different environments. Using standardized computational and statistical methods, the Microbiome Stress Project will leverage thousands of existing datasets to build a general framework for how microbial communities respond to environmental stress.
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Affiliation(s)
| | - Marie Simonin
- Department of Biology, Duke University, Durham, NC, United States
| | - Joanna R. Blaszczak
- Department of Biology, Duke University, Durham, NC, United States
- Flathead Lake Biological Station, University of Montana, Polson, MT, United States
| | - Jessica G. Ernakovich
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH, United States
| | - Sean M. Gibbons
- Institute for Systems Biology, Seattle, WA, United States
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, United States
- eScience Institute, University of Washington, Seattle, WA, United States
| | - Firas S. Midani
- Center for Genomic and Computational Biology, Duke University, Durham, NC, United States
| | - Alex D. Washburne
- Department of Biology, Duke University, Durham, NC, United States
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
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Núñez-Montero K, Barrientos L. Advances in Antarctic Research for Antimicrobial Discovery: A Comprehensive Narrative Review of Bacteria from Antarctic Environments as Potential Sources of Novel Antibiotic Compounds Against Human Pathogens and Microorganisms of Industrial Importance. Antibiotics (Basel) 2018; 7:E90. [PMID: 30347637 PMCID: PMC6316688 DOI: 10.3390/antibiotics7040090] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/05/2018] [Accepted: 10/04/2018] [Indexed: 12/16/2022] Open
Abstract
The recent emergence of antibiotic-resistant bacteria has become a critical public health problem. It is also a concern for industries, since multidrug-resistant microorganisms affect the production of many agricultural and food products of economic importance. Therefore, discovering new antibiotics is crucial for controlling pathogens in both clinical and industrial spheres. Most antibiotics have resulted from bioprospecting in natural environments. Today, however, the chances of making novel discoveries of bioactive molecules from various well-known sources have dramatically diminished. Consequently, unexplored and unique environments have become more likely avenues for discovering novel antimicrobial metabolites from bacteria. Due to their extreme polar environment, Antarctic bacteria in particular have been reported as a potential source for new antimicrobial compounds. We conducted a narrative review of the literature about findings relating to the production of antimicrobial compounds by Antarctic bacteria, showing how bacterial adaptation to extreme Antarctic conditions confers the ability to produce these compounds. We highlighted the diversity of antibiotic-producing Antarctic microorganisms, including the phyla Proteobacteria, Actinobacteria, Cyanobacteria, Firmicutes, and Bacteroidetes, which has led to the identification of new antibiotic molecules and supports the belief that research on Antarctic bacterial strains has important potential for biotechnology applications, while providing a better understanding of polar ecosystems.
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Affiliation(s)
- Kattia Núñez-Montero
- Laboratorio de Biología Molecular Aplicada, Centro de Excelencia en Medicina Traslacional, Universidad de La Frontera, Avenida Alemania 0458, 4810296 Temuco, Chile.
- Núcleo Científico y Tecnológico en Biorecursos (BIOREN), Universidad de La Frontera, Avenida Francisco Salazar 01145, 481123 Temuco, Chile.
- Centro de Investigación en Biotecnología, Escuela de Biología, Instituto Tecnológico de Costa Rica, 30101 Cartago, Costa Rica.
| | - Leticia Barrientos
- Laboratorio de Biología Molecular Aplicada, Centro de Excelencia en Medicina Traslacional, Universidad de La Frontera, Avenida Alemania 0458, 4810296 Temuco, Chile.
- Núcleo Científico y Tecnológico en Biorecursos (BIOREN), Universidad de La Frontera, Avenida Francisco Salazar 01145, 481123 Temuco, Chile.
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23
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First Record of Juncaceicola as Endophytic Fungi Associated with Deschampsia antarctica Desv. DIVERSITY 2018. [DOI: 10.3390/d10040107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In the current study, we present the molecular characterization of an endophyte fungus associated with the leaves of Deschampsia antarctica Desv. (Poaceae), a monocot species native to Antarctica. The isolate was obtained from 90 leaf fragments from two distinct collection sites, both located on Half Moon Island, South Shetland Islands and Maritime Antarctica. The internal transcribed spacer region (ITS) was sequenced and the endophytic fungus was identified as belonging to the genus Juncaceicola Tennakoon, Camporesi, Phook and K.D. Hyde (99% nucleotide sequence identity). When compared to all fungi of the genus Juncaceicola deposited in data base, our isolate showed greater proximity with Juncaceicola typharum, however, because it presents a low bootstrap value to be considered a new species, we treat it as Juncaceicola cf. typharum. Moreover, the identification of our isolate as belonging to the genus Juncaceicola makes this the first occurrence of a species of this genus to be associated with the leaves of Antarctic plants. This work is considered as a starting point for other studies with fungi of this genus associated with leaves of Deschampsia antarctica, as it presents results from two collection points on a single Antarctic island, suggesting that new sites and new Antarctic islands should be explored.
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Effect of Freeze-Thaw on a Midtemperate Soil Bacterial Community and the Correlation Network of Its Members. BIOMED RESEARCH INTERNATIONAL 2018; 2018:8412429. [PMID: 30050943 PMCID: PMC6040300 DOI: 10.1155/2018/8412429] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 04/17/2018] [Indexed: 11/17/2022]
Abstract
Freeze-thaw (FT) events can influence soil functions. However, the overall impact of FTs on soil bacterial communities, especially in temperate regions, remains unclear. In this study, soil samples were collected from a midtemperate region in the northeast of China, and three incubation tests were then designed with varied FT amplitudes (i.e., at a freezing temperature of −15, −9, and −3°C, respectively), frequencies of FT cycles (i.e., under one, six, and 15 FT cycles, respectively) and soil water content (SWC) values (i.e., at 10 and 30% SWC, respectively). High-throughput sequencing of 16S rRNA gene amplicons was performed and the functional profile was further predicted based on these data, in addition to examinations of bulk microbial properties. Data analyses suggested that, first of all, the FT amplitude significantly influenced the bulk microbial properties and bacterial community (composition and function); certain taxa showed a nonlinear response to the three amplitudes. Next, compared to a single FTC, multiple FT cycles had only minor effects on the bacterial functional capabilities, although the bulk microbial properties changed significantly after multiple FT cycles. In addition, the bacterial response to FTs was influenced by the SWC, characterized by the significantly different bacterial community structures (composition and function) and the opposite trends of enzyme activities. Finally, RDA plots and a correlation network assembled data from all soil samples across the three tests and suggested that bacterial response trajectories changed because some species were influenced mainly by other species (i.e., biotic environment) during FT processes.
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Ren J, Song C, Hou A, Song Y, Zhu X, Cagle GA. Shifts in soil bacterial and archaeal communities during freeze-thaw cycles in a seasonal frozen marsh, Northeast China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 625:782-791. [PMID: 29306166 DOI: 10.1016/j.scitotenv.2017.12.309] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 12/19/2017] [Accepted: 12/27/2017] [Indexed: 06/07/2023]
Abstract
Diurnal freeze-thaw cycles (FTCs) occur in the spring and autumn in boreal wetlands as soil temperatures rise above freezing during the day and fall below freezing at night. A surge in methane emissions from these systems is frequently documented during spring FTCs, accounting for a large portion of annual emissions. In boreal wetlands, methane is produced as a result of syntrophic microbial processes, mediated by a consortium of fermenting bacteria and methanogenic archaea. Further research is needed to determine whether FTCs enhance microbial metabolism related to methane production through the cryogenic decomposition of soil organic matter. Previous studies observed large methane emissions during the spring thawed period in the Sanjiang seasonal frozen marsh of Northeast China. To investigate how FTCs impact the soil microbial community and methanogen abundance and activity, we collected soil cores from the Sanjiang marsh during the FTCs of autumn 2014 and spring 2015. Methanogens were investigated based on expression level of the methyl coenzyme reductase (mcrA) gene, and soil bacterial and archaeal community structures were assessed by 16S rRNA gene sequencing. The results show that a decrease in bacteria and methanogens followed autumns FTCs, whereas an increase in bacteria and methanogens was observed following spring FTCs. The bacterial community structure, including Firmicutes and certain Deltaproteobacteria, was changed following autumn FTCs. Temperature and substrate were the primary factors regulating the abundance and composition of the microbial communities during autumn FTCs, whereas no factors significantly contributing to spring FTCs were identified. Acetoclastic methanogens from order Methanosarcinales were the dominant group at the beginning and end of both the autumn and spring FTCs. Active methanogens were significantly more abundant during the diurnal thawed period, indicating that the increasing number of FTCs predicted to occur with global climate change could potentially promote CH4 emissions in seasonal frozen marshes.
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Affiliation(s)
- Jiusheng Ren
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Changchun Song
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China.
| | - Aixin Hou
- Department of Environmental Sciences, College of the Coast and Environment, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Yanyu Song
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China
| | - Xiaoyan Zhu
- Key Laboratory of Songliao Aquatic Environment, Ministry of Education, Jilin Jianzhu University, Xincheng Street, District 5088, Changchun 130118, PR China
| | - Grace Ann Cagle
- Department of Environmental Sciences, College of the Coast and Environment, Louisiana State University, Baton Rouge, LA 70803, USA
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Taylor-Mulneix DL, Hamidou Soumana I, Linz B, Harvill ET. Evolution of Bordetellae from Environmental Microbes to Human Respiratory Pathogens: Amoebae as a Missing Link. Front Cell Infect Microbiol 2017; 7:510. [PMID: 29322035 PMCID: PMC5732149 DOI: 10.3389/fcimb.2017.00510] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 11/27/2017] [Indexed: 12/16/2022] Open
Abstract
The genus Bordetella comprises several bacterial species that colonize the respiratory tract of mammals. It includes B. pertussis, a human-restricted pathogen that is the causative agent of Whooping Cough. In contrast, the closely related species B. bronchiseptica colonizes a broad range of animals as well as immunocompromised humans. Recent metagenomic studies have identified known and novel bordetellae isolated from different environmental sources, providing a new perspective on their natural history. Using phylogenetic analysis, we have shown that human and animal pathogenic bordetellae have most likely evolved from ancestors that originated from soil and water. Our recent study found that B. bronchiseptica can evade amoebic predation and utilize Dictyostelium discoideum as an expansion and transmission vector, which suggests that the evolutionary pressure to evade the amoebic predator enabled the rise of bordetellae as respiratory pathogens. Interactions with amoeba may represent the starting point for bacterial adaptation to eukaryotic cells. However, as bacteria evolve and adapt to a novel host, they can become specialized and restricted to a specific host. B. pertussis is known to colonize and cause infection only in humans, and this specialization to a closed human-to-human lifecycle has involved genome reduction and the loss of ability to utilize amoeba as an environmental reservoir. The discoveries from studying the interaction of Bordetella species with amoeba will elicit a better understanding of the evolutionary history of these and other important human pathogens.
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Affiliation(s)
- Dawn L Taylor-Mulneix
- Department of Infectious Diseases, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Illiassou Hamidou Soumana
- Department of Infectious Diseases, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Bodo Linz
- Department of Infectious Diseases, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Eric T Harvill
- Department of Infectious Diseases, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
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Van Goethem MW, Makhalanyane TP, Cowan DA, Valverde A. Cyanobacteria and Alphaproteobacteria May Facilitate Cooperative Interactions in Niche Communities. Front Microbiol 2017; 8:2099. [PMID: 29118751 PMCID: PMC5660985 DOI: 10.3389/fmicb.2017.02099] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 10/13/2017] [Indexed: 01/04/2023] Open
Abstract
Hypoliths, microbial assemblages found below translucent rocks, provide important ecosystem services in deserts. While several studies have assessed microbial diversity of hot desert hypoliths and whether these communities are metabolically active, the interactions among taxa remain unclear. Here, we assessed the structure, diversity, and co-occurrence patterns of hypolithic communities from the hyperarid Namib Desert by comparing total (DNA) and potentially active (RNA) communities. The potentially active and total hypolithic communities differed in their composition and diversity, with significantly higher levels of Cyanobacteria and Alphaproteobacteria in potentially active hypoliths. Several phyla known to be abundant in total hypolithic communities were metabolically inactive, indicating that some hypolithic taxa may be dormant or dead. The potentially active hypolith network was highly modular in structure with almost exclusively positive co-occurrences (>95% of the total) between taxa. Members of the Cyanobacteria and Alphaproteobacteria were identified as potential keystone taxa, and exhibited numerous positive co-occurrences with other microbes, suggesting that these groups might have important roles in maintaining network topological structure despite their low abundance.
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Affiliation(s)
- Marc W Van Goethem
- Centre for Microbial Ecology and Genomics, Department of Genetics, University of Pretoria, Pretoria, South Africa
| | - Thulani P Makhalanyane
- Centre for Microbial Ecology and Genomics, Department of Genetics, University of Pretoria, Pretoria, South Africa
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Genetics, University of Pretoria, Pretoria, South Africa
| | - Angel Valverde
- Centre for Microbial Ecology and Genomics, Department of Genetics, University of Pretoria, Pretoria, South Africa
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