The Emergence of Different Functionally Equivalent PAH Degrading Microbial Communities from a Single Soil in Liquid PAH Enrichment Cultures and Soil Microcosms Receiving PAHs with and without Bioaugmentation

ABSTRACT The cyclic nitramine explosive CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) was examined in soil microcosms to determine whether it is biodegradable. CL-20 was incubated with a variety of soils. The explosive disappeared in all microcosms except the controls in which microbial activity had been inhibited. CL-20 was degraded most rapidly in garden soil. After 2 days of incubation, about 80% of the initial CL-20 had disappeared. A CL-20-degrading bacterial strain, Agrobacterium sp. strain JS71, was isolated from enrichment cultures containing garden soil as an inoculum, succinate as a carbon source, and CL-20 as a nitrogen source. Growth experiments revealed that strain JS71 used 3 mol of nitrogen per mol of CL-20.

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Environmental Fate of the Insecticide Chlorpyrifos in Soil Microcosms and Its Impact on Soil Microbial Communities

Recent Advances in Environmental Science from the Euro-Mediterranean and Surrounding Regions - Advances in Science, Technology & Innovation ◽

10.1007/978-3-319-70548-4_122 ◽

2018 ◽

pp. 387-389

Author(s):

Asma Ben Salem ◽

Nadine Rouard ◽

Marion Devers ◽

Jérémie Béguet ◽

Fabrice Martin-Laurent ◽

...

Keyword(s):

Microbial Communities ◽

Environmental Fate ◽

Soil Microbial Communities ◽

Soil Microcosms ◽

Soil Microbial

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Influence of temperature and soil water content on bacterial, archaeal and denitrifying microbial communities in drained fen grassland soil microcosms

FEMS Microbiology Ecology ◽

10.1111/j.1574-6941.2008.00555.x ◽

2008 ◽

Vol 66 (1) ◽

pp. 110-122 ◽

Cited By ~ 105

Author(s):

BlaÅ¾ Stres ◽

TjaÅ¡a DanevÄiÄ ◽

Levin Pal ◽

Mirna MrkonjiÄ‡ Fuka ◽

Lara Resman ◽

...

Keyword(s):

Microbial Communities ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Grassland Soil ◽

Soil Microcosms ◽

Influence Of Temperature

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Assessing Microbial Communities Related to Mercury Transformations in Contaminated Streambank Soils

Water Air & Soil Pollution ◽

10.1007/s11270-020-04978-0 ◽

2021 ◽

Vol 232 (1) ◽

Author(s):

Yazeed Abdelmageed ◽

Carrie Miller ◽

Carrie Sanders ◽

Timothy Egbo ◽

Alexander Johs ◽

...

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Contaminated Soils ◽

Microbial Community Composition ◽

Inorganic Mercury ◽

Amplicon Sequencing ◽

Soil Samples ◽

Rrna Gene ◽

Enrichment Cultures ◽

Relative Abundances

AbstractIn nature, the bioaccumulative potent neurotoxin methylmercury (MeHg) is produced from inorganic mercury (Hg) predominantly by anaerobic microorganisms. Hg-contaminated soils are a potential source of MeHg due to microbial activity. We examine streambank soils collected from the contaminated East Fork Poplar Creek (EFPC) in Tennessee, USA, where seasonal variations in MeHg levels have been observed throughout the year, suggesting active microbial Hg methylation. In this study, we characterized the microbial community in contaminated bank soil samples collected from two locations over a period of one year and compared the results to soil samples from an uncontaminated reference site with similar geochemistry (n = 12). Microbial community composition and diversity were assessed by 16S rRNA gene amplicon sequencing. Furthermore, to isolate potential methylators from soils, enrichment cultures were prepared using selective media. A set of three clade-specific primers targeting the gene hgcA were used to detect Hg methylators among the δ-Proteobacteria in EFPC bank soils across all seasons. Two families among the δ-Proteobacteria that have been previously associated with Hg methylation, Geobacteraceae and Syntrophobacteraceae, were found to be predominant with relative abundances of 0.13% and 4.0%, respectively. However, in soil enrichment cultures, Firmicutes were predominant among families associated with Hg methylation. Specifically, Clostridiaceae and Peptococcaceae and their genera Clostridium and Desulfosporosinus were among the ten most abundant genera with relative abundances of 2.6% and 1.7%, respectively. These results offer insights into the role of microbial communities on Hg transformation processes in contaminated bank soils in EFPC. Identifying the biogeochemical drivers of MeHg production is critical for future remediation efforts.

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Organic electron donors and terminal electron acceptors structure anaerobic microbial communities and interactions in a permanently stratified sulfidic lake

10.1101/2021.02.16.431432 ◽

2021 ◽

Author(s):

Connie A. Rojas ◽

Ana De Santiago Torio ◽

Serry Park ◽

Tanja Bosak ◽

Vanja Klepac-Ceraj

Keyword(s):

Community Structure ◽

Microbial Community ◽

Microbial Communities ◽

Microbial Community Structure ◽

Bacterial Communities ◽

Electron Acceptors ◽

Electron Donors ◽

Stratified Lakes ◽

Enrichment Cultures ◽

Organic Electron

AbstractThe extent to which nutrients structure microbial communities in permanently stratified lakes is not well understood. This study characterized microbial communities from the anoxic layers of the meromictic and sulfidic Fayetteville Green Lake (FGL), NY, and investigated the roles of organic electron donors and terminal electron acceptors in shaping microbial community structure and interactions. Bacterial communities from the permanently stratified layer below the chemocline (monimolimnion) and from enrichment cultures inoculated by lake sediments were analyzed using 16S rRNA gene sequencing. Results showed that anoxygenic phototrophs dominated microbial communities in the upper monimolimnion (21 m), which harbored little diversity, whereas the most diverse communities resided at the bottom of the lake (~52 m). Organic electron donors explained 54% of the variation in the microbial community structure in aphotic cultures enriched on an array of organic electron donors and different inorganic electron acceptors. Electron acceptors only explained 10% of the variation, but were stronger drivers of community assembly in enrichment cultures supplemented with acetate or butyrate compared to the cultures amended by chitin, lignin or cellulose. We identified a range of habitat generalists and habitat specialists in both the water column and enrichment samples using Levin’s index. Network analyses of interactions among microbial groups revealed Chlorobi and sulfate reducers as central to microbial interactions in the upper monimolimnion, while Syntrophaceae and other fermenting organisms were more important in the lower monimolimnion. The presence of photosynthetic microbes and communities that degrade chitin and cellulose much below the chemocline supported the downward transport of microbes, organic matter and oxidants from the surface and the chemocline. Collectively, our data suggest niche partitioning of bacterial communities by interactions that depend on the availability of different organic electron donors and terminal electron acceptors. Thus, light, as well as the diversity and availability of chemical resources drive community structure and function in FGL, and likely in other stratified, meromictic lakes.

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Microbial communities on biodegradable plastics under different fertilization practices in farmland soil microcosms

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.152184 ◽

2021 ◽

pp. 152184

Author(s):

Yu Zhang ◽

Jun Ma ◽

Patrick O'Connor ◽

Yong-Guan Zhu

Keyword(s):

Microbial Communities ◽

Biodegradable Plastics ◽

Soil Microcosms ◽

Farmland Soil

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Heavy Metal Tolerance of Fe(III)-Reducing Microbial Communities in Contaminated Creek Bank Soils

Applied and Environmental Microbiology ◽

10.1128/aem.02085-10 ◽

2011 ◽

Vol 77 (9) ◽

pp. 3132-3136 ◽

Cited By ~ 51

Author(s):

Eva-Maria Burkhardt ◽

Sebastian Bischoff ◽

Denise M. Akob ◽

Georg Büchel ◽

Kirsten Küsel

Keyword(s):

Heavy Metal ◽

Microbial Communities ◽

Metal Tolerance ◽

Heavy Metal Tolerance ◽

Gram Positive ◽

Content Type ◽

Soil Enrichment ◽

Enrichment Cultures ◽

Creek Bank

ABSTRACTFe(III)-reducing soil enrichment cultures can tolerate 100 μM Cu and Cd, 150 μM Co, 600 μM Ni, and 2,500 μM Zn. Metal-tolerant cultures were dominated byGeobacter-relatedDeltaproteobacteriaand Gram-positiveFirmicutesspp.(ClostridiaandSedimentibacter). A Cd- and Cu-tolerant Fe(III)-reducing coculture ofDesulfosporosinusandDesulfitobacteriumindicated the importance of theFirmicutesfor Fe(III) reduction in the presence of metals.

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