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Pallen MJ. The dynamic history of prokaryotic phyla: discovery, diversity and division. Int J Syst Evol Microbiol 2024; 74:006508. [PMID: 39250184 PMCID: PMC11382960 DOI: 10.1099/ijsem.0.006508] [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: 04/09/2024] [Accepted: 08/19/2024] [Indexed: 09/10/2024] Open
Abstract
Here, I review the dynamic history of prokaryotic phyla. Following leads set by Darwin, Haeckel and Woese, the concept of phylum has evolved from a group sharing common phenotypes to a set of organisms sharing a common ancestry, with modern taxonomy based on phylogenetic classifications drawn from macromolecular sequences. Phyla came as surprising latecomers to the formalities of prokaryotic nomenclature in 2021. Since then names have been validly published for 46 prokaryotic phyla, replacing some established names with neologisms, prompting criticism and debate within the scientific community. Molecular barcoding enabled phylogenetic analysis of microbial ecosystems without cultivation, leading to the identification of candidate divisions (or phyla) from diverse environments. The introduction of metagenome-assembled genomes marked a significant advance in identifying and classifying uncultured microbial phyla. The lumper-splitter dichotomy has led to disagreements, with experts cautioning against the pressure to create a profusion of new phyla and prominent databases adopting a conservative stance. The Candidatus designation has been widely used to provide provisional status to uncultured prokaryotic taxa, with phyla named under this convention now clearly surpassing those with validly published names. The Genome Taxonomy Database (GTDB) has offered a stable, standardized prokaryotic taxonomy with normalized taxonomic ranks, which has led to both lumping and splitting of pre-existing phyla. The GTDB framework introduced unwieldy alphanumeric placeholder labels, prompting recent publication of over 100 user-friendly Latinate names for unnamed prokaryotic phyla. Most candidate phyla remain 'known unknowns', with limited knowledge of their genomic diversity, ecological roles, or environments. Whether phyla still reflect significant evolutionary and ecological partitions across prokaryotic life remains an area of active debate. However, phyla remain of practical importance for microbiome analyses, particularly in clinical research. Despite potential diminishing returns in discovery of biodiversity, prokaryotic phyla offer extensive research opportunities for microbiologists for the foreseeable future.
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Affiliation(s)
- Mark J. Pallen
- Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, Norfolk, UK
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
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Krett G, Romsics C, Jurecska L, Bódai V, Erdélyi B, Márialigeti K, Nagymáté Z. Field test of a bioaugmentation agent for the bioremediation of chlorinated ethene contaminated sites. Biol Futur 2024; 75:289-299. [PMID: 39078604 DOI: 10.1007/s42977-024-00230-6] [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: 04/29/2024] [Accepted: 07/14/2024] [Indexed: 07/31/2024]
Abstract
Chlorinated ethenes are toxic compounds that were widely used in the past, and their improper handling and storage caused notable pollutions worldwide. In situ bioremediation by reductive dechlorination of bacteria is a cost-effective and ecologically friendly way to eliminate these pollutions. During the present study, the efficiency of a previously developed bioaugmentation agent combined with biostimulation was tested under field conditions in contaminated soil. Furthermore, the preservation of dechlorinating ability was also investigated in a long-term experiment. Initially, aerobic conditions were present in the groundwater with possible presence of anaerobic micro-niches providing habitat for Brocadia related anammox bacteria. "Candidatus Omnitrophus" was also identified as a dominant member of community then. Significant changes were detected after the biostimulation, anaerobic conditions established and most of the dominant OTUs were related to fermentative taxa (e.g. Clostridium, Trichococcus and Macillibacteroides). Dominant presence of vinyl-chloride coupled with the lack of vinyl-chloride reductase gene was observed. The most notable change after the bioaugmentation was the significant decrease in the pollutant quantities and the parallel increase in the vcrA gene copy numbers. Similar to post-biostimulation state, fermentative bacteria dominated the community. Bacterial community composition transformed considerably with time after the treatment, dominance of fermentative-mainly Firmicutes related-taxa decreased and chemolithotrophic bacteria became abundant, but the dechlorinating potential of the community remained and could be induced by the reappearance of the pollutants even after 4 years.
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Affiliation(s)
- Gergely Krett
- Department of Microbiology, Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary.
| | - Csaba Romsics
- Department of Microbiology, Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary
| | - Laura Jurecska
- Department of Microbiology, Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary
| | | | | | - Károly Márialigeti
- Department of Microbiology, Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary
| | - Zsuzsanna Nagymáté
- Department of Microbiology, Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary
- Fermentia Ltd, Berlini Utca 47, 1045, Budapest, Hungary
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Harbeitner RC, Wittmers F, Yung CCM, Eckmann CA, Hehenberger E, Blum M, Needham DM, Worden AZ. Gradients of bacteria in the oceanic water column reveal finely-resolved vertical distributions. PLoS One 2024; 19:e0298139. [PMID: 38564528 PMCID: PMC10986988 DOI: 10.1371/journal.pone.0298139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 01/16/2024] [Indexed: 04/04/2024] Open
Abstract
Bacterial communities directly influence ecological processes in the ocean, and depth has a major influence due to the changeover in primary energy sources between the sunlit photic zone and dark ocean. Here, we examine the abundance and diversity of bacteria in Monterey Bay depth profiles collected from the surface to just above the sediments (e.g., 2000 m). Bacterial abundance in these Pacific Ocean samples decreased by >1 order of magnitude, from 1.22 ±0.69 ×106 cells ml-1 in the variable photic zone to 1.44 ± 0.25 ×105 and 6.71 ± 1.23 ×104 cells ml-1 in the mesopelagic and bathypelagic, respectively. V1-V2 16S rRNA gene profiling showed diversity increased sharply between the photic and mesopelagic zones. Weighted Gene Correlation Network Analysis clustered co-occurring bacterial amplicon sequence variants (ASVs) into seven subnetwork modules, of which five strongly correlated with depth-related factors. Within surface-associated modules there was a clear distinction between a 'copiotrophic' module, correlating with chlorophyll and dominated by e.g., Flavobacteriales and Rhodobacteraceae, and an 'oligotrophic' module dominated by diverse Oceanospirillales (such as uncultured JL-ETNP-Y6, SAR86) and Pelagibacterales. Phylogenetic reconstructions of Pelagibacterales and SAR324 using full-length 16S rRNA gene data revealed several additional subclades, expanding known microdiversity within these abundant lineages, including new Pelagibacterales subclades Ia.B, Id, and IIc, which comprised 4-10% of amplicons depending on the subclade and depth zone. SAR324 and Oceanospirillales dominated in the mesopelagic, with SAR324 clade II exhibiting its highest relative abundances (17±4%) in the lower mesopelagic (300-750 m). The two newly-identified SAR324 clades showed highest relative abundances in the photic zone (clade III), while clade IV was extremely low in relative abundance, but present across dark ocean depths. Hierarchical clustering placed microbial communities from 900 m samples with those from the bathypelagic, where Marinimicrobia was distinctively relatively abundant. The patterns resolved herein, through high resolution and statistical replication, establish baselines for marine bacterial abundance and taxonomic distributions across the Monterey Bay water column, against which future change can be assessed.
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Affiliation(s)
- Rachel C. Harbeitner
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, CA, United States of America
- Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, DE, Germany
| | - Fabian Wittmers
- Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, DE, Germany
- Marine Biological Laboratory, Woods Hole, MA, United States of America
| | - Charmaine C. M. Yung
- Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, DE, Germany
| | - Charlotte A. Eckmann
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, CA, United States of America
- Marine Biological Laboratory, Woods Hole, MA, United States of America
| | - Elisabeth Hehenberger
- Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, DE, Germany
| | - Marguerite Blum
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, United States of America
| | - David M. Needham
- Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, DE, Germany
| | - Alexandra Z. Worden
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, CA, United States of America
- Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, DE, Germany
- Marine Biological Laboratory, Woods Hole, MA, United States of America
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Kim HS, Park K, Jo HY, Kwon MJ. Weathering extents and anthropogenic influences shape the soil bacterial community along a subsurface zonation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162570. [PMID: 36889395 DOI: 10.1016/j.scitotenv.2023.162570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 02/26/2023] [Accepted: 02/27/2023] [Indexed: 06/18/2023]
Abstract
Subsurface environments are composed of various active soil layers with dynamic biogeochemical interactions. We investigated soil bacterial community composition and geochemical properties along a vertical soil profile, which was categorized into surface, unsaturated, groundwater fluctuated, and saturated zones, in a testbed site formerly used as farmland for several decades. We hypothesized that weathering extent and anthropogenic inputs influence changes in the community structure and assembly processes and have distinct contributions along the subsurface zonation. Elemental distribution in each zone was strongly affected by the extent of chemical weathering. A 16S rRNA gene analysis indicated that bacterial richness (alpha diversity) was highest in the surface zone, and also higher in the fluctuated zone, than in unsaturated and saturated zones due to the effects of high organic matter, high nutrient levels, and/or aerobic conditions. Redundancy analysis showed that major elements (P, Na), a trace element (Pb), NO3, and the weathering extent were key driving forces shaping bacterial community composition along the subsurface zonation. Assembly processes were governed by specific ecological niches, such as homogeneous selection, in the unsaturated, fluctuated, and saturated zones, while in the surface zone, they were dominated by dispersal limitation. These findings together suggest that the vertical variation in soil bacterial community assembly is zone-specific and shaped by the relative influences of deterministic vs. stochastic processes. Our results provide novel insights into the relationships between bacterial communities, environmental factors, and anthropogenic influences (e.g., fertilization, groundwater, soil contamination), and into the roles of specific ecological niches and subsurface biogeochemical processes in these relationships.
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Affiliation(s)
- Han-Suk Kim
- Department of Earth and Environmental Sciences, Korea University, Seoul 02841, South Korea
| | - Kanghyun Park
- Department of Earth and Environmental Sciences, Korea University, Seoul 02841, South Korea
| | - Ho Young Jo
- Department of Earth and Environmental Sciences, Korea University, Seoul 02841, South Korea
| | - Man Jae Kwon
- Department of Earth and Environmental Sciences, Korea University, Seoul 02841, South Korea.
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Wang Z, Jimenez-Fernandez O, Osenbrück K, Schwientek M, Schloter M, Fleckenstein JH, Lueders T. Streambed microbial communities in the transition zone between groundwater and a first-order stream as impacted by bidirectional water exchange. WATER RESEARCH 2022; 217:118334. [PMID: 35397370 DOI: 10.1016/j.watres.2022.118334] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/15/2022] [Accepted: 03/19/2022] [Indexed: 06/14/2023]
Abstract
The input of nitrate and other agricultural pollutants in higher-order streams largely derives from first-order streams. The streambed as the transition zone between groundwater and stream water has a decisive impact on the attenuation of such pollutants. This reactivity is not yet well understood for lower-order agricultural streams, which are often anthropogenically altered and lack the streambed complexity allowing for extensive hyporheic exchange. Reactive hot spots in such streambeds have been hypothesized as a function of hydrology, which controls the local gaining (groundwater exfiltration) or losing (infiltration) of stream water. However, streambed microbial communities and activities associated with such reactive zones remain mostly uncharted. In this study, sediments of a first-order agriculturally impacted stream in southern Germany were investigated. Along with a hydraulic dissection of distinct gaining and losing reaches of the stream, community composition and the abundance of bacterial communities in the streambed were investigated using PacBio long-read sequencing of bacterial 16S rRNA gene amplicons, and qPCR of bacterial 16S rRNA and denitrification genes (nirK and nirS). We show that bidirectional water exchange between groundwater and the stream represents an important control for sediment microbiota, especially for nitrate-reducing populations. Typical heterotrophic denitrifiers were most abundant in a midstream net losing section, while up- and downstream net gaining sections were associated with an enrichment of sulfur-oxidizing potential nitrate reducers affiliated with Sulfuricurvum and Thiobacillus spp. Dispersal-based community assembly was found to dominate such spots of groundwater exfiltration. Our results indicate a coupling of N- and S-cycling processes in the streambed of an agricultural first-order stream, and a prominent control of microbiology by hydrology and hydrochemistry in situ. Such detailed local heterogeneities in exchange fluxes and streambed microbiomes have not been reported to date, but seem relevant for understanding the reactivity of lower-order streams.
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Affiliation(s)
- Zhe Wang
- Chair of Ecological Microbiology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany; Institute of Groundwater Ecology, Helmholtz Zentrum München - German Research Centre for Environmental Health, Neuherberg, Germany; School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Oscar Jimenez-Fernandez
- Center for Applied Geoscience, University of Tübingen, Tübingen, Germany; Department of Hydrogeology, Helmholtz-Zentrum für Umweltforschung GmbH - UFZ, Leipzig, Germany
| | - Karsten Osenbrück
- Center for Applied Geoscience, University of Tübingen, Tübingen, Germany; Federal Institute for Geosciences and Natural Resources (BGR), Hannover, Germany
| | - Marc Schwientek
- Center for Applied Geoscience, University of Tübingen, Tübingen, Germany
| | - Michael Schloter
- Chair of Soil Science, Technical University of Munich, Freising, Germany; Research Unit for Comparative Microbiome Analyses, Helmholtz Zentrum München - German Research Centre for Environmental Health, Neuherberg, Germany
| | - Jan H Fleckenstein
- Department of Hydrogeology, Helmholtz-Zentrum für Umweltforschung GmbH - UFZ, Leipzig, Germany; Hydrologic Modelling Unit, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Tillmann Lueders
- Chair of Ecological Microbiology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany.
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6
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Chakraborty A, Suchy M, Hubert CRJ, Ryan MC. Vertical stratification of microbial communities and isotope geochemistry tie groundwater denitrification to sampling location within a nitrate-contaminated aquifer. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 820:153092. [PMID: 35038526 DOI: 10.1016/j.scitotenv.2022.153092] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 12/29/2021] [Accepted: 01/09/2022] [Indexed: 06/14/2023]
Abstract
Nitrate pollution is a major threat to groundwater quality in agricultural areas. Natural attenuation of nitrate in contaminated aquifers is mediated by denitrifying microbial populations in anoxic environments. Vertical distribution of denitrifying microbial communities in aquifers is greatly influenced by groundwater redox conditions, local hydrogeological parameters, and seasonal variability in groundwater flow and recharge. In this study, we investigated groundwater geochemistry and the composition of bacterial and archaeal communities with increasing depth in a shallow nitrate-contaminated aquifer in British Columbia, Canada. High-resolution passive diffusion sampling was conducted to collect groundwater at 10-cm intervals from 4 to 20 m below ground surface (mbgs) in the aquifer. Geochemical analyses of major ions indicated a general shift in the groundwater chemistry below 16 mbgs including decreasing chloride concentrations that suggest two-end member mixing of shallow and deep groundwater with different chemistries. A redoxcline was further observed within a 2 m transition zone at 18-20 mbgs characterized by sharp declines in nitrate concentrations and increases in sulfate and total inorganic carbon. Excursions in δ15N-NO3- and δ18O-NO3- in the same depth interval are consistent with denitrification, and a concomitant decrease in δ34S-SO42- suggested that denitrification was coupled to sulfide or sulfur oxidation. Microbial communities within this depth interval were significantly dissimilar to those above and below, featuring putative lithotrophic denitrifying bacteria belonging to the genera Sulfurifustis, Sulfuritalea and Sulfuricella. These lineages were detected in greatest abundance at 19 mbgs while the abundances of putative heterotrophic sulfate-reducing bacteria belonging to the genus Desulfosporosinus were greatest at 20 mbgs. In addition to help distinguish denitrification from mixing-induced changes in groundwater chemistry, the above observed vertical stratification of the microbial key players connects nitrate removal to the locations of the aquifer sampled.
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Affiliation(s)
- Anirban Chakraborty
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada.
| | - Martin Suchy
- Environment and Climate Change Canada, Vancouver, British Columbia, Canada
| | - Casey R J Hubert
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - M Cathryn Ryan
- Department of Geoscience, University of Calgary, Calgary, Alberta, Canada
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7
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Shu WS, Huang LN. Microbial diversity in extreme environments. Nat Rev Microbiol 2022; 20:219-235. [PMID: 34754082 DOI: 10.1038/s41579-021-00648-y] [Citation(s) in RCA: 146] [Impact Index Per Article: 73.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2021] [Indexed: 01/02/2023]
Abstract
A wide array of microorganisms, including many novel, phylogenetically deeply rooted taxa, survive and thrive in extreme environments. These unique and reduced-complexity ecosystems offer a tremendous opportunity for studying the structure, function and evolution of natural microbial communities. Marker gene surveys have resolved patterns and ecological drivers of these extremophile assemblages, revealing a vast uncultured microbial diversity and the often predominance of archaea in the most extreme conditions. New omics studies have uncovered linkages between community function and environmental variables, and have enabled discovery and genomic characterization of major new lineages that substantially expand microbial diversity and change the structure of the tree of life. These efforts have significantly advanced our understanding of the diversity, ecology and evolution of microorganisms populating Earth's extreme environments, and have facilitated the exploration of microbiota and processes in more complex ecosystems.
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Affiliation(s)
- Wen-Sheng Shu
- School of Life Sciences, South China Normal University, Guangzhou, People's Republic of China.
| | - Li-Nan Huang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China.
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Rokubacteria in Northern Peatlands: Habitat Preferences and Diversity Patterns. Microorganisms 2021; 10:microorganisms10010011. [PMID: 35056460 PMCID: PMC8780371 DOI: 10.3390/microorganisms10010011] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/16/2021] [Accepted: 12/20/2021] [Indexed: 01/04/2023] Open
Abstract
Rokubacteria is a phylogenetic clade of as-yet-uncultivated prokaryotes, which are detected in diverse terrestrial habitats and are commonly addressed as members of the rare biosphere. This clade was originally described as a candidate phylum; however, based on the results of comparative genome analysis, was later defined as the order-level lineage, Rokubacteriales, within the phylum Methylomirabilota. The physiology and lifestyles of these bacteria are poorly understood. A dataset of 16S rRNA gene reads retrieved from four boreal raised bogs and six eutrophic fens was examined for the presence of the Rokubacteriales; the latter were detected exclusively in fens. Their relative abundance varied between 0.2 and 4% of all bacteria and was positively correlated with pH, total nitrogen content, and availability of Ca and Mg. To test an earlier published hypothesis regarding the presence of methanotrophic capabilities in Rokubacteria, peat samples were incubated with 10% methane for four weeks. No response to methane availability was detected for the Rokubacteriales, while clear a increase in relative abundance was observed for the conventional Methylococcales methanotrophs. The search for methane monooxygenase encoding genes in 60 currently available Rokubacteriales metagenomes yielded negative results, although copper-containing monooxygenases were encoded by some members of this order. This study suggests that peat-inhabiting Rokubacteriales are neutrophilic non-methanotrophic bacteria that colonize nitrogen-rich wetlands.
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Hwang Y, Schulze-Makuch D, Arens FL, Saenz JS, Adam PS, Sager C, Bornemann TLV, Zhao W, Zhang Y, Airo A, Schloter M, Probst AJ. Leave no stone unturned: individually adapted xerotolerant Thaumarchaeota sheltered below the boulders of the Atacama Desert hyperarid core. MICROBIOME 2021; 9:234. [PMID: 34836555 PMCID: PMC8627038 DOI: 10.1186/s40168-021-01177-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND The hyperarid core of the Atacama Desert is an extremely harsh environment thought to be colonized by only a few heterotrophic bacterial species. Current concepts for understanding this extreme ecosystem are mainly based on the diversity of these few species, yet a substantial area of the Atacama Desert hyperarid topsoil is covered by expansive boulder accumulations, whose underlying microbiomes have not been investigated so far. With the hypothesis that these sheltered soils harbor uniquely adapted microbiomes, we compared metagenomes and geochemistry between soils below and beside boulders across three distantly located boulder accumulations in the Atacama Desert hyperarid core. RESULTS Genome-resolved metagenomics of eleven samples revealed substantially different microbial communities in soils below and beside boulders, despite the presence of shared species. Archaea were found in significantly higher relative abundance below the boulders across all samples within distances of up to 205 km. These key taxa belong to a novel genus of ammonia-oxidizing Thaumarchaeota, Candidatus Nitrosodeserticola. We resolved eight mid-to-high quality genomes of this genus and used comparative genomics to analyze its pangenome and site-specific adaptations. Ca. Nitrosodeserticola genomes contain genes for ammonia oxidation, the 3-hydroxypropionate/4-hydroxybutyrate carbon fixation pathway, and acetate utilization indicating a chemolithoautotrophic and mixotrophic lifestyle. They also possess the capacity for tolerating extreme environmental conditions as highlighted by the presence of genes against oxidative stress and DNA damage. Site-specific adaptations of the genomes included the presence of additional genes for heavy metal transporters, multiple types of ATP synthases, and divergent genes for aquaporins. CONCLUSION We provide the first genomic characterization of hyperarid soil microbiomes below the boulders in the Atacama Desert, and report abundant and highly adapted Thaumarchaeaota with ammonia oxidation and carbon fixation potential. Ca. Nitrosodeserticola genomes provide the first metabolic and physiological insight into a thaumarchaeal lineage found in globally distributed terrestrial habitats characterized by various environmental stresses. We consequently expand not only the known genetic repertoire of Thaumarchaeota but also the diversity and microbiome functioning in hyperarid ecosystems. Video Abstract.
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Affiliation(s)
- Yunha Hwang
- Astrobiology Group, Center for Astronomy & Astrophysics, Technische Universität Berlin, 10623, Berlin, Germany
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141, Essen, Germany
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Dirk Schulze-Makuch
- Astrobiology Group, Center for Astronomy & Astrophysics, Technische Universität Berlin, 10623, Berlin, Germany.
- Section Geomicrobiology, German Research Centre for Geosciences (GFZ), 14473, Potsdam, Germany.
- Department of Experimental Limnology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), 12587, Stechlin, Germany.
- School of the Environment, Washington State University, Pullman, WA, 99164, USA.
| | - Felix L Arens
- Astrobiology Group, Center for Astronomy & Astrophysics, Technische Universität Berlin, 10623, Berlin, Germany
| | - Johan S Saenz
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München, 85758, Oberschleißheim, Germany
| | - Panagiotis S Adam
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141, Essen, Germany
| | - Christof Sager
- Astrobiology Group, Center for Astronomy & Astrophysics, Technische Universität Berlin, 10623, Berlin, Germany
| | - Till L V Bornemann
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141, Essen, Germany
| | - Weishu Zhao
- Department of Cell and Molecular Biology, College of the Environment and Life Sciences, University of Rhode Island, Kingston, RI, USA
| | - Ying Zhang
- Department of Cell and Molecular Biology, College of the Environment and Life Sciences, University of Rhode Island, Kingston, RI, USA
| | - Alessandro Airo
- Astrobiology Group, Center for Astronomy & Astrophysics, Technische Universität Berlin, 10623, Berlin, Germany
| | - Michael Schloter
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München, 85758, Oberschleißheim, Germany
| | - Alexander J Probst
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141, Essen, Germany.
- Centre of Water and Environmental Research (ZWU), University of Duisburg-Essen, Universitätsstraße 5, 45141 , Essen, Germany.
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Microbial Diversity and Function in Shallow Subsurface Sediment and Oceanic Lithosphere of the Atlantis Massif. mBio 2021; 12:e0049021. [PMID: 34340550 PMCID: PMC8406227 DOI: 10.1128/mbio.00490-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The marine lithospheric subsurface is one of the largest biospheres on Earth; however, little is known about the identity and ecological function of microorganisms found in low abundance in this habitat, though these organisms impact global-scale biogeochemical cycling. Here, we describe the diversity and metabolic potential of sediment and endolithic (within rock) microbial communities found in ultrasmall amounts (101 to 104 cells cm−3) in the subsurface of the Atlantis Massif, an oceanic core complex on the Mid-Atlantic Ridge that was sampled on International Ocean Discovery Program (IODP) Expedition 357. This study used fluorescence-activated cell sorting (FACS) to enable the first amplicon, metagenomic, and single-cell genomic study of the shallow (<20 m below seafloor) subsurface of an actively serpentinizing marine system. The shallow subsurface biosphere of the Atlantis Massif was found to be distinct from communities observed in the nearby Lost City alkaline hydrothermal fluids and chimneys, yet similar to other low-temperature, aerobic subsurface settings. Genes associated with autotrophy were rare, although heterotrophy and aerobic carbon monoxide and formate cycling metabolisms were identified. Overall, this study reveals that the shallow subsurface of an oceanic core complex hosts a biosphere that is not fueled by active serpentinization reactions and by-products.
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11
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Veshareh MJ, Nick HM. A novel relationship for the maximum specific growth rate of a microbial guild. FEMS Microbiol Lett 2021; 368:6293845. [PMID: 34089333 DOI: 10.1093/femsle/fnab064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/02/2021] [Indexed: 11/13/2022] Open
Abstract
One of the major parameters that characterizes the kinetics of microbial processes is the maximum specific growth rate. The maximum specific growth rate for a single microorganism (${\mu _{max}}$) is fairly constant. However, a certain microbial process is typically catalyzed by a group of microorganisms (guild) that have various ${\mu _{max}}$ values. In many occasions, it is not feasible to breakdown a guild into its constituent microorganisms. Therefore, it is a common practice to assume a constant maximum specific growth rate for the guild ($\acute{\mu}_{max}$) and determine its value by fitting experimental data. This assumption is valid for natural environments, where microbial guilds are stabilized and dominated by microorganisms that grow optimally in those environments' conditions. However, a change in an environment's conditions will trigger a community shift by favoring some of the microorganisms. This shift leads to a variable ${\acute{\mu}_{max}}$ as long as substrate availability is significantly higher than substrate affinity constant. In this work, it is illustrated that the assumption of constant ${\acute{\mu}_{max}}$ may underestimate or overestimate microbial growth. To circumvent this, a novel relationship that characterizes changes in ${\acute{\mu}_{max}}$ under abundant nutrient availability is proposed. The proposed relationship is evaluated for various random microbial guilds in batch experiments.
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Affiliation(s)
- Moein Jahanbani Veshareh
- Danish Hydrocarbon Research and Technology Centre, Technical University of Denmark, 375 Elektrovej, DK-2800 kgs Lyngby, Denmark
| | - Hamidreza M Nick
- Danish Hydrocarbon Research and Technology Centre, Technical University of Denmark, 375 Elektrovej, DK-2800 kgs Lyngby, Denmark
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Frey B, Walthert L, Perez-Mon C, Stierli B, Köchli R, Dharmarajah A, Brunner I. Deep Soil Layers of Drought-Exposed Forests Harbor Poorly Known Bacterial and Fungal Communities. Front Microbiol 2021; 12:674160. [PMID: 34025630 PMCID: PMC8137989 DOI: 10.3389/fmicb.2021.674160] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/12/2021] [Indexed: 12/31/2022] Open
Abstract
Soil microorganisms such as bacteria and fungi play important roles in the biogeochemical cycling of soil nutrients, because they act as decomposers or are mutualistic or antagonistic symbionts, thereby influencing plant growth and health. In the present study, we investigated the vertical distribution of the soil microbiome to a depth of 2 m in Swiss drought-exposed forests of European beech and oaks on calcareous bedrock. We aimed to disentangle the effects of soil depth, tree (beech, oak), and substrate (soil, roots) on microbial abundance, diversity, and community structure. With increasing soil depth, organic carbon, nitrogen, and clay content decreased significantly. Similarly, fine root biomass, microbial biomass (DNA content, fungal abundance), and microbial alpha-diversity decreased and were consequently significantly related to these physicochemical parameters. In contrast, bacterial abundance tended to increase with soil depth, and the bacteria to fungi ratio increased significantly with greater depth. Tree species was only significantly related to the fungal Shannon index but not to the bacterial Shannon index. Microbial community analyses revealed that bacterial and fungal communities varied significantly across the soil layers, more strongly for bacteria than for fungi. Both communities were also significantly affected by tree species and substrate. In deep soil layers, poorly known bacterial taxa from Nitrospirae, Chloroflexi, Rokubacteria, Gemmatimonadetes, Firmicutes and GAL 15 were overrepresented. Furthermore, archaeal phyla such as Thaumarchaeota and Euryarchaeota were more abundant in subsoils than topsoils. Fungal taxa that were predominantly found in deep soil layers belong to the ectomycorrhizal Boletus luridus and Hydnum vesterholtii. Both taxa are reported for the first time in such deep soil layers. Saprotrophic fungal taxa predominantly recorded in deep soil layers were unknown species of Xylaria. Finally, our results show that the microbial community structure found in fine roots was well represented in the bulk soil. Overall, we recorded poorly known bacterial and archaeal phyla, as well as ectomycorrhizal fungi that were not previously known to colonize deep soil layers. Our study contributes to an integrated perspective on the vertical distribution of the soil microbiome at a fine spatial scale in drought-exposed forests.
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Affiliation(s)
- Beat Frey
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Lorenz Walthert
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Carla Perez-Mon
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Beat Stierli
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Roger Köchli
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Alexander Dharmarajah
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Ivano Brunner
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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Dai X, Wang Y, Luo L, Pfiffner SM, Li G, Dong Z, Xu Z, Dong H, Huang L. Detection of the deep biosphere in metamorphic rocks from the Chinese continental scientific drilling. GEOBIOLOGY 2021; 19:278-291. [PMID: 33559972 DOI: 10.1111/gbi.12430] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 01/17/2021] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
It is generally accepted that there is a vast, well-populated biosphere in the subsurface, but the depth limit of the terrestrial biosphere has yet to be determined, largely because of the lack of access to the subsurface. Here as part of the Chinese Continental Scientific Drilling (CCSD) project in eastern China, we acquired continuous rock cores and endeavored to probe the depth limit of the biosphere and the depth-dependent distribution of microorganisms at a geologically unique site, that is, a convergent plate boundary. Microbiological analyses of ultra-high-pressure metamorphic rock cores taken from the ground surface to 5,158-meter reveal that microbial distribution was continuous up to a depth of ~4,850 m, where temperature was estimated to be ~137°C. The metabolic state of these organisms at such great depth remains to be determined. Microbial abundance, ranging from 103 to 108 cells/g, was also related to porosity, but not to the depth and rock composition. In addition, microbial diversity systematically decreased with depth. Our results support the notion that temperature is a key factor in determining the lower limit of the biosphere in the continental subsurface.
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Affiliation(s)
- Xin Dai
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yuanliang Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Liqiang Luo
- National Research Center for Geoanalysis, Chinese Academy of Geological Sciences, Beijing, China
| | - Susan M Pfiffner
- Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN, USA
| | - Guangyu Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Zhiyang Dong
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Zhiqin Xu
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, China
| | - Hailiang Dong
- Center for Geomicrobiology and Biogeochemistry Research, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, China
| | - Li Huang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
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Hao J, Chai YN, Lopes LD, Ordóñez RA, Wright EE, Archontoulis S, Schachtman DP. The Effects of Soil Depth on the Structure of Microbial Communities in Agricultural Soils in Iowa, USA. Appl Environ Microbiol 2021; 87:AEM.02673-20. [PMID: 33310710 PMCID: PMC7851703 DOI: 10.1128/aem.02673-20] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 12/01/2020] [Indexed: 02/03/2023] Open
Abstract
This study investigated the differences in microbial community abundance, composition and diversity throughout the depth profiles in soils collected from corn and soybean fields in lowa, USA using 16S rRNA amplicon sequencing. The results revealed decreased richness and diversity in microbial communities at increasing soil depth. Soil microbial community composition differed due to crop type only in the top 60 cm and due to location only in the top 90 cm. While the relative abundance of most phyla decreased in deep soils, the relative abundance of the phylum Proteobacteria increased and dominated agricultural soils below the depth of 90 cm. Although soil depth was the most important factor shaping microbial communities, edaphic factors including soil organic matter, soil bulk density and the length of time that deep soils were saturated with water were all significant factors explaining the variation in soil microbial community composition. Soil organic matter showed the highest correlation with the exponential decrease in bacterial abundance with depth. A greater understanding of how soil depth influences the diversity and composition of soil microbial communities is vital for guiding sampling approaches in agricultural soils where plant roots extend beyond the upper soil profile. In the long term a greater knowledge of the influence of depth on microbial communities should contribute to new strategies that enhance the sustainability of soil which is a precious resource for food security.IMPORTANCE Determining how microbial properties change across different soils and within the soil depth profile, will be potentially beneficial to understanding the long-term processes that are involved in the health of agricultural ecosystems. Most literature on soil microbes has been restricted to the easily accessible surface soils. However, deep soils are important in soil formation, carbon sequestration, and in providing nutrients and water for plants. In the most productive agricultural systems in the USA where soybean and corn are grown, crop plant roots extend into the deeper regions of soils (> 100 cm), but little is known about the taxonomic diversity or the factors that shape deep soil microbial communities. The findings reported here highlight the importance of soil depth in shaping microbial communities, provide new information about edaphic factors that influence the deep soil communities and reveal more detailed information on taxa that exist in deep agricultural soils.
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Affiliation(s)
- Jingjie Hao
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Yen Ning Chai
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Lucas Dantas Lopes
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Raziel A Ordóñez
- Department of Agronomy, Iowa State University, Agronomy Hall, Ames, Iowa, USA
- Department of Plant Science and Industries Building, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Emily E Wright
- Department of Agronomy, Iowa State University, Agronomy Hall, Ames, Iowa, USA
| | | | - Daniel P Schachtman
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
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15
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Determining Soil Microbial Communities and Their Influence on Ganoderma Disease Incidences in Oil Palm ( Elaeis guineensis) via High-Throughput Sequencing. BIOLOGY 2020; 9:biology9120424. [PMID: 33260913 PMCID: PMC7760618 DOI: 10.3390/biology9120424] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 01/04/2023]
Abstract
Simple Summary Biological and physicochemical soil factors involved in the incidence of the basal stem rot (BSR) disease in an oil palm (Elaeis guineensis) plantation in Malaysia were characterized. Blenheim soil with a low BSR disease incidence and Bernam soil with high BSR disease incidence were analyzed and observed to have differences in composition and diversity of soil prokaryotic and eukaryotic communities. Blenheim soil with a high pH and calcium was shown to have higher prokaryotic and eukaryotic diversity compared to Bernam soil. High abundances of rare metabolically diverse and versatile bacterial taxa, bacterial taxa that increased with the introduction of biocontrol agents, potential disease-suppressive bacteria, and bacterivorous flagellates were observed in Blenheim soil. In contrast, Bernam soil was predominantly characterized by potential disease-inducible bacterial taxa. A combination of both abiotic and biotic elements might be essential in driving disease-suppressive soil microbiome toward Ganoderma BSR in Blenheim soil. Abstract Basal stem rot (BSR), caused by Ganoderma boninense, is the most devastating oil palm disease in South East Asia, costing US$500 million annually. Various soil physicochemical parameters have been associated with an increase in BSR incidences. However, very little attention has been directed to understanding the relationship between soil microbiome and BSR incidence in oil palm fields. The prokaryotic and eukaryotic microbial diversities of two coastal soils, Blenheim soil (Typic Quartzipsamment—calcareous shell deposits, light texture) with low disease incidence (1.9%) and Bernam soil (Typic Endoaquept—non-acid sulfate) with high disease incidence (33.1%), were determined using the 16S (V3–V4 region) and 18S (V9 region) rRNA amplicon sequencing. Soil physicochemical properties (pH, electrical conductivity, soil organic matter, nitrogen, phosphorus, cation exchange capacity, exchangeable cations, micronutrients, and soil physical parameters) were also analyzed for the two coastal soils. Results revealed that Blenheim soil comprises higher prokaryotic and eukaryotic diversities, accompanied by higher pH and calcium content. Blenheim soil was observed to have a higher relative abundance of bacterial taxa associated with disease suppression such as Calditrichaeota, Zixibacteria, GAL15, Omnitrophicaeota, Rokubacteria, AKYG587 (Planctomycetes), JdFR-76 (Calditrichaeota), and Rubrobacter (Actinobacteria). In contrast, Bernam soil had a higher proportion of other bacterial taxa, Chloroflexi and Acidothermus (Actinobacteria). Cercomonas (Cercozoa) and Calcarisporiella (Ascomycota) were eukaryotes that are abundant in Blenheim soil, while Uronema (Ciliophora) and mammals were present in higher abundance in Bernam soil. Some of the bacterial taxa have been reported previously in disease-suppressive and -conducive soils as potential disease-suppressive or disease-inducible bacteria. Furthermore, Cercomonas was reported previously as potential bacterivorous flagellates involved in the selection of highly toxic biocontrol bacteria, which might contribute to disease suppression indirectly. The results from this study may provide valuable information related to soil microbial community structures and their association with soil characteristics and soil susceptibility to Ganoderma.
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Sjöberg S, Stairs CW, Allard B, Homa F, Martin T, Sjöberg V, Ettema TJG, Dupraz C. Microbiomes in a manganese oxide producing ecosystem in the Ytterby mine, Sweden: impact on metal mobility. FEMS Microbiol Ecol 2020; 96:fiaa169. [PMID: 32815988 PMCID: PMC7593233 DOI: 10.1093/femsec/fiaa169] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 08/13/2020] [Indexed: 12/28/2022] Open
Abstract
Microbe-mediated precipitation of Mn-oxides enriched in rare earth elements (REE) and other trace elements was discovered in tunnels leading to the main shaft of the Ytterby mine, Sweden. Defining the spatial distribution of microorganisms and elements in this ecosystem provide a better understanding of specific niches and parameters driving the emergence of these communities and associated mineral precipitates. Along with elemental analyses, high-throughput sequencing of the following four subsystems were conducted: (i) water seeping from a rock fracture into the tunnel, (ii) Mn-oxides and associated biofilm; referred to as the Ytterby Black Substance (YBS) biofilm (iii) biofilm forming bubbles on the Mn-oxides; referred to as the bubble biofilm and (iv) fracture water that has passed through the biofilms. Each subsystem hosts a specific collection of microorganisms. Differentially abundant bacteria in the YBS biofilm were identified within the Rhizobiales (e.g. Pedomicrobium), PLTA13 Gammaproteobacteria, Pirellulaceae, Hyphomonadaceae, Blastocatellia and Nitrospira. These taxa, likely driving the Mn-oxide production, were not detected in the fracture water. This biofilm binds Mn, REE and other trace elements in an efficient, dynamic process, as indicated by substantial depletion of these metals from the fracture water as it passes through the Mn deposit zone. Microbe-mediated oxidation of Mn(II) and formation of Mn(III/IV)-oxides can thus have considerable local environmental impact by removing metals from aquatic environments.
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Affiliation(s)
- Susanne Sjöberg
- Department of Geological Sciences, Stockholm University, Svante Arrhenius väg 8, SE-106 91 Stockholm, Sweden
| | - Courtney W Stairs
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, SE-751 23 Uppsala, Sweden
| | - Bert Allard
- Man-Technology-Environment Research Centre (MTM), Örebro University, SE-701 82 Örebro, Sweden
| | - Felix Homa
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, SE-751 23 Uppsala, Sweden
- Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Stippeneng 4, 6708WE Wageningen, The Netherlands
| | - Tom Martin
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, SE-751 23 Uppsala, Sweden
| | - Viktor Sjöberg
- Man-Technology-Environment Research Centre (MTM), Örebro University, SE-701 82 Örebro, Sweden
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, SE-751 23 Uppsala, Sweden
- Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Stippeneng 4, 6708WE Wageningen, The Netherlands
| | - Christophe Dupraz
- Department of Geological Sciences, Stockholm University, Svante Arrhenius väg 8, SE-106 91 Stockholm, Sweden
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Song D, Jiang Z, Ma T, Dong Y, Shi L. Bacterial and Archaeal Diversity and Abundance in Shallow Subsurface Clay Sediments at Jianghan Plain, China. Front Microbiol 2020; 11:572560. [PMID: 33193171 PMCID: PMC7642157 DOI: 10.3389/fmicb.2020.572560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 09/01/2020] [Indexed: 11/13/2022] Open
Abstract
Clay layers are common in subsurface where microbial activities play an important role in impacting the biogeochemical properties of adjacent aquifers. In this study, we analyzed the community structure and abundance of bacteria and archaea in response to geochemical properties of six clay sediments at different depths in a borehole (112°34'0″E, 30°36'21″N) of Jianghan Plain (JHP), China. Our results suggested that the top two clay layers were oxic, while the remaining bottom four clay layers were anoxic. Both high-throughput sequencing and qPCR of 16S rRNA gene showed relatively high abundance of archaea (up to 60%) in three of the anoxic clay layers. Furthermore, microbial communities in these clay sediments showed distinct vertical stratification, which may be impacted by changes in concentrations of sulfate, HCl-extractable Fe2+ and total organic carbon (TOC) in the sediments. In the upper two oxic clay layers, identification of phyla Thaumarchaeota (11.2%) and Nitrosporales (1.2%) implied nitrification in these layers. In the two anoxic clay layers beneath the oxic zone, high abundances of Anaeromyxobacter, Chloroflexi bacterium RBG 16_58_14 and Deltaproteobacteria, suggested the reductions of nitrate, iron and sulfate. Remarkably, a significant portion of Bathyarchaeota (∼25%) inhabited in the bottom two anoxic clay layers, which may indicate archaeal anaerobic degradation of TOC by these organisms. The results of this study provide the first systematic understandings of microbial activities in subsurface clay layers at JHP, which may help develop microorganism-based solutions for mitigating subsurface contaminations.
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Affiliation(s)
- Dandan Song
- School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Zhou Jiang
- School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Teng Ma
- School of Environmental Studies, China University of Geosciences, Wuhan, China
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Yiran Dong
- School of Environmental Studies, China University of Geosciences, Wuhan, China
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Liang Shi
- School of Environmental Studies, China University of Geosciences, Wuhan, China
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
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18
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Hot in Cold: Microbial Life in the Hottest Springs in Permafrost. Microorganisms 2020; 8:microorganisms8091308. [PMID: 32867302 PMCID: PMC7565842 DOI: 10.3390/microorganisms8091308] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 08/22/2020] [Accepted: 08/25/2020] [Indexed: 12/26/2022] Open
Abstract
Chukotka is an arctic region located in the continuous permafrost zone, but thermal springs are abundant there. In this study, for the first time, the microbial communities of the Chukotka hot springs (CHS) biofilms and sediments with temperatures 54–94 °C were investigated and analyzed by NGS sequencing of 16S rRNA gene amplicons. In microbial mats (54–75 °C), phototrophic bacteria of genus Chloroflexus dominated (up to 89% of all prokaryotes), while Aquificae were the most numerous at higher temperatures in Fe-rich sediments and filamentous “streamers” (up to 92%). The electron donors typical for Aquificae, such as H2S and H2, are absent or present only in trace amounts, and the prevalence of Aquificae might be connected with their ability to oxidize the ferrous iron present in CHS sediments. Armatimonadetes, Proteobacteria, Deinococcus-Thermus, Dictyoglomi, and Thermotogae, as well as uncultured bacteria (candidate divisions Oct-Spa1-106, GAL15, and OPB56), were numerous, and Cyanobacteria were present in low numbers. Archaea (less than 8% of the total community of each tested spring) belonged to Bathyarchaeota, Aigarchaeota, and Thaumarchaeota. The geographical location and the predominantly autotrophic microbial community, built on mechanisms other than the sulfur cycle-based ones, make CHS a special and unique terrestrial geothermal ecosystem.
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Abstract
Manganese is among Earth’s most abundant elements. Its oxidation had long been theorized1, yet undemonstrated2–4, to fuel chemolithoautotrophic microbial growth. Here, an enrichment culture exhibiting Mn(II)-oxidation-dependent, exponential growth was refined to a two species co-culture. Oxidation required viable bacteria at permissive temperatures, resulting in the generation of small Mn oxide nodules to which the cells associated. The majority member of the culture, ‘Candidatus Manganitrophus noduliformans’, affiliates within phylum Nitrospirae (Nitrospirota) but is distantly related to known Nitrospira and Leptospirillum species. The minority member has been isolated, but does not oxidise Mn(II) alone. Stable isotope probing revealed Mn(II)-oxidation-dependent, 13CO2-fixation into cellular biomass. Transcriptomics reveals candidate pathways for coupling extracellular manganese oxidation to aerobic energy conservation and to autotrophic CO2-fixation. These findings expand the known diversity of inorganic metabolisms supporting life, while completing a biogeochemical energy cycle for manganese5,6, one that may interface with other major global elemental cycles.
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20
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Zhong S, Chen Q, Hu J, Liu S, Qiao S, Ni J, Sun W. Vertical distribution of microbial communities and their response to metal(loid)s along the vadose zone-aquifer sediments. J Appl Microbiol 2020; 129:1657-1673. [PMID: 32533753 DOI: 10.1111/jam.14742] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 05/20/2020] [Accepted: 06/03/2020] [Indexed: 01/30/2023]
Abstract
AIMS This study attempted to demonstrate the vertical shift in bacterial, archaeal and fungal communities along the vadose zone-aquifer sediments and their respective responses to environmental factors. METHODS AND RESULTS We collected samples from the vadose zone and three aquifer sediments along a 42·5 m bore of a typical agricultural land. The results showed that the bacterial community shifted greatly with depth. The classes of Actinobacteria (19·5%) and NC10 (11·0%) were abundant in the vadose zone while Alphaproteobacteria (22·3%) and Gammaproteobacteria (20·1%) were enriched in the aquifer. Archaeal and fungal communities were relatively more homogeneous with no significant trend as a function of depth. Process analyses further indicated that selection dominated in the bacterial community, whereas stochastic processes governed archaeal and fungal communities. Moreover environment-bacteria interaction analysis showed that metal(loid)s, especially alkali metal, had a closer correlation with the bacterial community than physicochemical variables. CONCLUSIONS Depth strongly affected bacterial rather than archaeal and fungal communities. Metal(loid)s prevailed over physicochemical variables in shaping the bacterial community in the vadose zone-aquifer continuum. SIGNIFICANCE AND IMPACT OF THE STUDY Our study provides a new perspective on the structure of microbial communities from the vadose zone to the deep aquifers.
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Affiliation(s)
- S Zhong
- College of Environmental Sciences and Engineering, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing, China
| | - Q Chen
- College of Environmental Sciences and Engineering, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing, China
| | - J Hu
- College of Environmental Sciences and Engineering, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing, China
| | - S Liu
- College of Environmental Sciences and Engineering, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing, China
| | - S Qiao
- College of Environmental Sciences and Engineering, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing, China
| | - J Ni
- College of Environmental Sciences and Engineering, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing, China
| | - W Sun
- State Key Lab Plateau Ecology and Agriculture, Qinghai University, Xining, Qinghai, People's Republic of China
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21
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Sheremet A, Jones GM, Jarett J, Bowers RM, Bedard I, Culham C, Eloe-Fadrosh EA, Ivanova N, Malmstrom RR, Grasby SE, Woyke T, Dunfield PF. Ecological and genomic analyses of candidate phylum WPS-2 bacteria in an unvegetated soil. Environ Microbiol 2020; 22:3143-3157. [PMID: 32372527 DOI: 10.1111/1462-2920.15054] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 04/28/2020] [Accepted: 04/29/2020] [Indexed: 12/01/2022]
Abstract
Members of the bacterial candidate phylum WPS-2 (or Eremiobacterota) are abundant in several dry, bare soil environments. In a bare soil deposited by an extinct iron-sulfur spring, we found that WPS-2 comprised up to 24% of the bacterial community and up to 108 cells per g of soil based on 16S rRNA gene sequencing and quantification. A single genus-level cluster (Ca. Rubrimentiphilum) predominated in bare soils but was less abundant in adjacent forest. Nearly complete genomes of Ca. Rubrimentiphilum were recovered as single amplified genomes (SAGs) and metagenome-assembled genomes (MAGs). Surprisingly, given the abundance of WPS-2 in bare soils, the genomes did not indicate any capacity for autotrophy, phototrophy, or trace gas metabolism. Instead, they suggest a predominantly aerobic organoheterotrophic lifestyle, perhaps based on scavenging amino acids, nucleotides, and complex oligopeptides, along with lithotrophic capacity on thiosulfate. Network analyses of the entire community showed that some species of Chloroflexi, Actinobacteria, and candidate phylum AD3 (or Dormibacterota) co-occurred with Ca. Rubrimentiphilum and may represent ecological or metabolic partners. We propose that Ca. Rubrimentiphilum act as efficient heterotrophic scavengers. Combined with previous studies, these data suggest that the phylum WPS-2 includes bacteria with diverse metabolic capabilities.
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Affiliation(s)
- Andriy Sheremet
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
| | - Gareth M Jones
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
| | - Jessica Jarett
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | - Robert M Bowers
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | - Isaac Bedard
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
| | - Cassandra Culham
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
| | | | - Natalia Ivanova
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | - Rex R Malmstrom
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | | | - Tanja Woyke
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | - Peter F Dunfield
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
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Wei Y, Jin Y, Zhang W. Treatment of High-Concentration Wastewater from an Oil and Gas Field via a Paired Sequencing Batch and Ceramic Membrane Reactor. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17061953. [PMID: 32192017 PMCID: PMC7143815 DOI: 10.3390/ijerph17061953] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/07/2020] [Accepted: 03/13/2020] [Indexed: 01/31/2023]
Abstract
A sequencing batch reactor (SBR) and a ceramic membrane bioreactor (CMBR) were used in conjunction (SBR+CMBR) to treat high-concentration oil and gas field wastewater (HCOGW) from the China National Offshore Oil Corporation Zhanjiang Branch (Zhanjiang, Guangdong, China). The chemical oxygen demand (COD) and the oil concentrations in the wastewater were 20,000–76,000 and 600–2200 mg/L, respectively. After the SBR+CMBR process, the effluent COD and oil content values were less than 250 mg/L and 2 mg/L, respectively, which met the third level of the Integrated Wastewater Discharge Standards of China (GB8978-1996). Through microbiological analysis, it was found that the CMBR domesticated a previously unreported functional microorganism (JF922467.1) that successfully formed a new microbial ecosystem suitable for HCOGW treatment. In conjunction with the SBR process, the CMBR process effectively reduced pollutant concentrations in HCOGW. Moreover, economic analyses indicated that the total investment required to implement the proposed infrastructure would be approximately 671,776.61 USD, and the per-unit water treatment cost would be 1.04 USD/m3.
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Affiliation(s)
- Yuan Wei
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China;
| | - Yue Jin
- College of Civil Engineering and Architecture, Guilin University of Technology, Guilin 541004, China;
- Correspondence: ; Tel.: +86-773-253-6922; Fax: +86-773-253-6922
| | - Wenjie Zhang
- College of Civil Engineering and Architecture, Guilin University of Technology, Guilin 541004, China;
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Abstract
While most bacterial and archaeal taxa living in surface soils remain undescribed, this problem is exacerbated in deeper soils, owing to the unique oligotrophic conditions found in the subsurface. Additionally, previous studies of soil microbiomes have focused almost exclusively on surface soils, even though the microbes living in deeper soils also play critical roles in a wide range of biogeochemical processes. We examined soils collected from 20 distinct profiles across the United States to characterize the bacterial and archaeal communities that live in subsurface soils and to determine whether there are consistent changes in soil microbial communities with depth across a wide range of soil and environmental conditions. We found that bacterial and archaeal diversity generally decreased with depth, as did the degree of similarity of microbial communities to those found in surface horizons. We observed five phyla that consistently increased in relative abundance with depth across our soil profiles: Chloroflexi, Nitrospirae, Euryarchaeota, and candidate phyla GAL15 and Dormibacteraeota (formerly AD3). Leveraging the unusually high abundance of Dormibacteraeota at depth, we assembled genomes representative of this candidate phylum and identified traits that are likely to be beneficial in low-nutrient environments, including the synthesis and storage of carbohydrates, the potential to use carbon monoxide (CO) as a supplemental energy source, and the ability to form spores. Together these attributes likely allow members of the candidate phylum Dormibacteraeota to flourish in deeper soils and provide insight into the survival and growth strategies employed by the microbes that thrive in oligotrophic soil environments.IMPORTANCE Soil profiles are rarely homogeneous. Resource availability and microbial abundances typically decrease with soil depth, but microbes found in deeper horizons are still important components of terrestrial ecosystems. By studying 20 soil profiles across the United States, we documented consistent changes in soil bacterial and archaeal communities with depth. Deeper soils harbored communities distinct from those of the more commonly studied surface horizons. Most notably, we found that the candidate phylum Dormibacteraeota (formerly AD3) was often dominant in subsurface soils, and we used genomes from uncultivated members of this group to identify why these taxa are able to thrive in such resource-limited environments. Simply digging deeper into soil can reveal a surprising number of novel microbes with unique adaptations to oligotrophic subsurface conditions.
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Soil bacterial communities in the Brazilian Cerrado: Response to vegetation type and management. ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY 2019. [DOI: 10.1016/j.actao.2019.103463] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Biosynthetic capacity, metabolic variety and unusual biology in the CPR and DPANN radiations. Nat Rev Microbiol 2019; 16:629-645. [PMID: 30181663 DOI: 10.1038/s41579-018-0076-2] [Citation(s) in RCA: 216] [Impact Index Per Article: 43.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Candidate phyla radiation (CPR) bacteria and DPANN (an acronym of the names of the first included phyla) archaea are massive radiations of organisms that are widely distributed across Earth's environments, yet we know little about them. Initial indications are that they are consistently distinct from essentially all other bacteria and archaea owing to their small cell and genome sizes, limited metabolic capacities and often episymbiotic associations with other bacteria and archaea. In this Analysis, we investigate their biology and variations in metabolic capacities by analysis of approximately 1,000 genomes reconstructed from several metagenomics-based studies. We find that they are not monolithic in terms of metabolism but rather harbour a diversity of capacities consistent with a range of lifestyles and degrees of dependence on other organisms. Notably, however, certain CPR and DPANN groups seem to have exceedingly minimal biosynthetic capacities, whereas others could potentially be free living. Understanding of these microorganisms is important from the perspective of evolutionary studies and because their interactions with other organisms are likely to shape natural microbiome function.
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Smith HJ, Zelaya AJ, De León KB, Chakraborty R, Elias DA, Hazen TC, Arkin AP, Cunningham AB, Fields MW. Impact of hydrologic boundaries on microbial planktonic and biofilm communities in shallow terrestrial subsurface environments. FEMS Microbiol Ecol 2018; 94:5107865. [PMID: 30265315 PMCID: PMC6192502 DOI: 10.1093/femsec/fiy191] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 09/26/2018] [Indexed: 12/12/2022] Open
Abstract
Subsurface environments contain a large proportion of planetary microbial biomass and harbor diverse communities responsible for mediating biogeochemical cycles important to groundwater used by human society for consumption, irrigation, agriculture and industry. Within the saturated zone, capillary fringe and vadose zones, microorganisms can reside in two distinct phases (planktonic or biofilm), and significant differences in community composition, structure and activity between free-living and attached communities are commonly accepted. However, largely due to sampling constraints and the challenges of working with solid substrata, the contribution of each phase to subsurface processes is largely unresolved. Here, we synthesize current information on the diversity and activity of shallow freshwater subsurface habitats, discuss the challenges associated with sampling planktonic and biofilm communities across spatial, temporal and geological gradients, and discuss how biofilms may be constrained within shallow terrestrial subsurface aquifers. We suggest that merging traditional activity measurements and sequencing/-omics technologies with hydrological parameters important to sediment biofilm assembly and stability will help delineate key system parameters. Ultimately, integration will enhance our understanding of shallow subsurface ecophysiology in terms of bulk-flow through porous media and distinguish the respective activities of sessile microbial communities from more transient planktonic communities to ecosystem service and maintenance.
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Affiliation(s)
- H J Smith
- Center for Biofilm Engineering, Montana State University, Bozeman, MT
- ENIGMA (www.enigma.lbl.gov) Environmental Genomics and Systems Biology Division, Biosciences Area, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS:977, Berkeley, CA 94720
| | - A J Zelaya
- Center for Biofilm Engineering, Montana State University, Bozeman, MT
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT
- ENIGMA (www.enigma.lbl.gov) Environmental Genomics and Systems Biology Division, Biosciences Area, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS:977, Berkeley, CA 94720
| | - K B De León
- Department of Biochemistry, University of Missouri, Columbia, MO
- ENIGMA (www.enigma.lbl.gov) Environmental Genomics and Systems Biology Division, Biosciences Area, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS:977, Berkeley, CA 94720
| | - R Chakraborty
- Climate and Ecosystems Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA
- ENIGMA (www.enigma.lbl.gov) Environmental Genomics and Systems Biology Division, Biosciences Area, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS:977, Berkeley, CA 94720
| | - D A Elias
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN
- ENIGMA (www.enigma.lbl.gov) Environmental Genomics and Systems Biology Division, Biosciences Area, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS:977, Berkeley, CA 94720
| | - T C Hazen
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN
- ENIGMA (www.enigma.lbl.gov) Environmental Genomics and Systems Biology Division, Biosciences Area, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS:977, Berkeley, CA 94720
| | - A P Arkin
- Department of Bioengineering, Lawrence Berkeley National Laboratory, Berkeley, CA
- ENIGMA (www.enigma.lbl.gov) Environmental Genomics and Systems Biology Division, Biosciences Area, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS:977, Berkeley, CA 94720
| | - A B Cunningham
- Center for Biofilm Engineering, Montana State University, Bozeman, MT
- Department of Civil Engineering, Montana State University, Montana State University, Bozeman, MT
| | - M W Fields
- Center for Biofilm Engineering, Montana State University, Bozeman, MT
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT
- ENIGMA (www.enigma.lbl.gov) Environmental Genomics and Systems Biology Division, Biosciences Area, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS:977, Berkeley, CA 94720
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Sirisena KA, Daughney CJ, Moreau M, Sim DA, Lee CK, Cary SC, Ryan KG, Chambers GK. Bacterial bioclusters relate to hydrochemistry in New Zealand groundwater. FEMS Microbiol Ecol 2018; 94:5078342. [DOI: 10.1093/femsec/fiy170] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 08/22/2018] [Indexed: 12/31/2022] Open
Affiliation(s)
- Kosala A Sirisena
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand
- Department of Zoology, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka
- Center for Water Quality and Algae Research, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka
| | | | - Magali Moreau
- GNS Science, PO Box 30368, Lower Hutt 5040, New Zealand
| | - Dalice A Sim
- School of Mathematics, Statistics and Operations Research, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand
| | - Charles K Lee
- School of Science, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand
| | - Stephen C Cary
- School of Science, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand
| | - Ken G Ryan
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand
| | - Geoffrey K Chambers
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand
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Tahon G, Tytgat B, Lebbe L, Carlier A, Willems A. Abditibacterium utsteinense sp. nov., the first cultivated member of candidate phylum FBP, isolated from ice-free Antarctic soil samples. Syst Appl Microbiol 2018; 41:279-290. [DOI: 10.1016/j.syapm.2018.01.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 01/20/2018] [Accepted: 01/29/2018] [Indexed: 10/18/2022]
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Lee JH, Lee BJ. Microbial Reduction of Fe(III) and SO 42- and Associated Microbial Communities in the Alluvial Aquifer Groundwater and Sediments. MICROBIAL ECOLOGY 2018; 76:182-191. [PMID: 29177753 DOI: 10.1007/s00248-017-1119-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 11/21/2017] [Indexed: 06/07/2023]
Abstract
Agricultural demands continuously increased use of groundwater, causing drawdown of water table and need of artificial recharge using adjacent stream waters. River water intrusion into groundwater can alter the geochemical and microbiological characteristics in the aquifer and subsurface. In an effort to investigate the subsurface biogeochemical activities before operation of artificial recharge at the test site, established at the bank of Nakdong River, Changwon, South Korea, organic carbon transported from river water to groundwater was mimicked and the effect on the indigenous microbial communities was investigated with the microcosm incubations of the groundwater and subsurface sediments. Laboratory incubations indicated microbial reduction of Fe(III) and sulfate. Next-generation Illumina MiSeq sequences of V4 region of 16S rRNA gene provided that the shifts of microbial taxa to Fe(III)-reducing and/or sulfate-reducing microorganisms such as Geobacter, Albidiferax, Desulfocapsa, Desulfuromonas, and Desulfovibrio were in good correlation with the sequential flourishment of microbial reduction of Fe(III) and sulfate as the incubations progressed. This suggests the potential role of dissolved organic carbons migrated with the river water into groundwater in the managed aquifer recharge system on the indigenous microbial community composition and following alterations of subsurface biogeochemistry and microbial metabolic activities.
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Affiliation(s)
- Ji-Hoon Lee
- Department of Bioenvironmental Chemistry, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, 54896, Republic of Korea.
| | - Bong-Joo Lee
- Groundwater Department, Korea Institute of Geoscience and Mineral Resources, Daejeon, Republic of Korea
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Differential depth distribution of microbial function and putative symbionts through sediment-hosted aquifers in the deep terrestrial subsurface. Nat Microbiol 2018; 3:328-336. [PMID: 29379208 PMCID: PMC6792436 DOI: 10.1038/s41564-017-0098-y] [Citation(s) in RCA: 142] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 12/12/2017] [Indexed: 11/16/2022]
Abstract
An enormous diversity of previously unknown bacteria and archaea has been discovered recently, yet their functional capacities and distributions in the terrestrial subsurface remain uncertain. Here, we continually sampled a CO2-driven geyser (Colorado Plateau, Utah, USA) over its 5-day eruption cycle to test the hypothesis that stratified, sandstone-hosted aquifers sampled over three phases of the eruption cycle have microbial communities that differ both in membership and function. Genome-resolved metagenomics, single-cell genomics and geochemical analyses confirmed this hypothesis and linked microorganisms to groundwater compositions from different depths. Autotrophic Candidatus “Altiarchaeum sp.” and phylogenetically deep-branching nanoarchaea dominate the deepest groundwater. A nanoarchaeon with limited metabolic capacity is inferred to be a potential symbiont of the Ca. “Altiarchaeum”. Candidate Phyla Radiation bacteria are also present in the deepest groundwater and they are relatively abundant in water from intermediate depths. During the recovery phase of the geyser, microaerophilic Fe- and S-oxidizers have high in situ genome replication rates. Autotrophic Sulfurimonas sustained by aerobic sulfide oxidation and with the capacity for N2 fixation dominate the shallow aquifer. Overall, 104 different phylum-level lineages are present in water from these subsurface environments, with uncultivated archaea and bacteria partitioned to the deeper subsurface. Analysis of a CO2-driven geyser over a complete eruption cycle showed temporal changes in microbial community composition and function, associated with eruption phase and aquifer water depth, and revealed a putative archaeal symbiosis.
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Zhang Z, Zhou X, Tian L, Ma L, Luo S, Zhang J, Li X, Tian C. Fungal communities in ancient peatlands developed from different periods in the Sanjiang Plain, China. PLoS One 2017; 12:e0187575. [PMID: 29236715 PMCID: PMC5728540 DOI: 10.1371/journal.pone.0187575] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 10/23/2017] [Indexed: 01/08/2023] Open
Abstract
Peatlands in the Sanjiang Plain could be more vulnerable to global warming because they are located at the southernmost boundary of northern peatlands. Unlike bacteria, fungi are often overlooked, even though they play important roles in substance circulation in the peatland ecosystems. Accordingly, it is imperative that we deepen our understanding of fungal community structure and diversity in the peatlands. In this study, high-throughput Illumina sequencing was used to study the fungal communities in three fens in the Sanjiang Plain, located at the southern edge of northern peatlands. Peat soil was collected from the three fens which developed during different periods. A total of 463,198 fungal ITS sequences were obtained, and these sequences were classified into at least six phyla, 21 classes, more than 60 orders and over 200 genera. The fungal community structures were distinct in the three sites and were dominated by Ascomycota and Basidiomycota. However, there were no significant differences between these three fens in any α-diversity index (p > 0.05). Soil age and the carbon (C) accumulation rate, as well as total carbon (TC), total nitrogen (TN), C/N ratio, and bulk density were found to be closely related to the abundance of several dominant fungal taxa. We captured a rich fungal community and confirmed that the dominant taxa were those which were frequently detected in other northern peatlands. Soil age and the C accumulation rate were found to play important roles in shaping the fungal community structure.
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Affiliation(s)
- Zhenqing Zhang
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Xue Zhou
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Lei Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Lina Ma
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Shasha Luo
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Jianfeng Zhang
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Xiujun Li
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Chunjie Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
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Becraft ED, Woyke T, Jarett J, Ivanova N, Godoy-Vitorino F, Poulton N, Brown JM, Brown J, Lau MCY, Onstott T, Eisen JA, Moser D, Stepanauskas R. Rokubacteria: Genomic Giants among the Uncultured Bacterial Phyla. Front Microbiol 2017; 8:2264. [PMID: 29234309 PMCID: PMC5712423 DOI: 10.3389/fmicb.2017.02264] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 11/02/2017] [Indexed: 01/08/2023] Open
Abstract
Recent advances in single-cell genomic and metagenomic techniques have facilitated the discovery of numerous previously unknown, deep branches of the tree of life that lack cultured representatives. Many of these candidate phyla are composed of microorganisms with minimalistic, streamlined genomes lacking some core metabolic pathways, which may contribute to their resistance to growth in pure culture. Here we analyzed single-cell genomes and metagenome bins to show that the "Candidate phylum Rokubacteria," formerly known as SPAM, represents an interesting exception, by having large genomes (6-8 Mbps), high GC content (66-71%), and the potential for a versatile, mixotrophic metabolism. We also observed an unusually high genomic heterogeneity among individual Rokubacteria cells in the studied samples. These features may have contributed to the limited recovery of sequences of this candidate phylum in prior cultivation and metagenomic studies. Our analyses suggest that Rokubacteria are distributed globally in diverse terrestrial ecosystems, including soils, the rhizosphere, volcanic mud, oil wells, aquifers, and the deep subsurface, with no reports from marine environments to date.
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Affiliation(s)
- Eric D Becraft
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States
| | - Tanja Woyke
- Joint Genome Institute, Walnut Creek, CA, United States
| | | | | | - Filipa Godoy-Vitorino
- Department of Natural Sciences, Inter American University of Puerto Rico, San Juan, Puerto Rico
| | - Nicole Poulton
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States
| | - Julia M Brown
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States
| | - Joseph Brown
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States
| | - M C Y Lau
- Department of Geosciences, Princeton University, Princeton, NJ, United States
| | - Tullis Onstott
- Department of Geosciences, Princeton University, Princeton, NJ, United States
| | - Jonathan A Eisen
- College of Biological Sciences, Genome Center, University of California, Davis, Davis, CA, United States
| | - Duane Moser
- Desert Research Institute, Las Vegas, NV, United States
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Zhou X, Zhang Z, Tian L, Li X, Tian C. Microbial communities in peatlands along a chronosequence on the Sanjiang Plain, China. Sci Rep 2017; 7:9567. [PMID: 28852134 PMCID: PMC5575048 DOI: 10.1038/s41598-017-10436-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 08/09/2017] [Indexed: 02/01/2023] Open
Abstract
Microbial communities play crucial roles in the global carbon cycle, particularly in peatland ecosystems under climate change. The peatlands of the Sanjiang Plain could be highly vulnerable to global warming because they are mainly located at the southern limit of northern peatlands. In this study, the alpha diversity and composition of bacterial communities in three different minerotrophic fens along a chronosequence were investigated. We captured a rich microbial community that included many rare operational taxonomic units (OTUs) but was dominated by a few bacterial classes that have frequently been detected in other peatland ecosystems. Notably, a large diversity of methanotrophs affiliated with Alpha- and Gammaproteobacteria was also detected. Bacterial alpha diversity and composition varied as a function of peat depth and its associated physical-chemical properties, such as total carbon, total nitrogen, pH and bulk density. We also found that bacterial community turnover (beta diversity) to be significantly correlated with soil age, whereas bacterial alpha diversity was not.
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Affiliation(s)
- Xue Zhou
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Zhenqing Zhang
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Lei Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China.,University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiujun Li
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Chunjie Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China.
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Qafoku O, Pearce CI, Neumann A, Kovarik L, Zhu M, Ilton ES, Bowden ME, Resch CT, Arey BW, Arenholz E, Felmy AR, Rosso KM. Tc(VII) and Cr(VI) Interaction with Naturally Reduced Ferruginous Smectite from a Redox Transition Zone. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:9042-9052. [PMID: 28703576 DOI: 10.1021/acs.est.7b02191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Fe(II)-rich clay minerals found in subsurface redox transition zones (RTZs) can serve as important sources of electron equivalents limiting the transport of redox-active contaminants. While most laboratory reactivity studies are based on reduced model clays, the reactivity of naturally reduced field samples remains poorly explored. Characterization of the clay size fraction of a fine-grained unit from the RTZ interface at the Hanford site, Washington, including mineralogy, crystal chemistry, and Fe(II)/(III) content, indicates that ferruginous montmorillonite is the dominant mineralogical component. Oxic and anoxic fractions differ significantly in Fe(II) natural content, but FeTOTAL remains constant, demonstrating no Fe loss during its reduction-oxidation cyclings. At native pH of 8.6, the anoxic fraction, despite its significant Fe(II), ∼23% of FeTOTAL, exhibits minimal reactivity with TcO4- and CrO42- and much slower reaction kinetics than those measured in studies with biologically/chemically reduced model clays. Reduction capacity is enhanced by added/sorbed Fe(II) (if Fe(II)SORBED > 8% clay Fe(II)LABILE); however, the kinetics of this conceptually surface-mediated reaction remain sluggish. Surface-sensitive Fe L-edge X-ray absorption spectroscopy shows that Fe(II)SORBED and the resulting reducing equivalents are not available in the outermost few nanometers of clay surfaces. Slow kinetics thus appear related to diffusion-limited access to electron equivalents retained within the clay mineral structure.
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Affiliation(s)
- Odeta Qafoku
- Pacific Northwest National Laboratory , P.O. Box 999, MS K8-96, Richland, Washington 99352, United States
| | - Carolyn I Pearce
- Pacific Northwest National Laboratory , P.O. Box 999, MS K8-96, Richland, Washington 99352, United States
| | - Anke Neumann
- Newcastle University , Newcastle NE1 7RU, United Kingdom
| | - Libor Kovarik
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory , Richland, Washington 99352, United States
| | - Mengqiang Zhu
- University of Wyoming , Laramie, Wyoming 82071, United States
| | - Eugene S Ilton
- Pacific Northwest National Laboratory , P.O. Box 999, MS K8-96, Richland, Washington 99352, United States
| | - Mark E Bowden
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory , Richland, Washington 99352, United States
| | - Charles T Resch
- Pacific Northwest National Laboratory , P.O. Box 999, MS K8-96, Richland, Washington 99352, United States
| | - Bruce W Arey
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory , Richland, Washington 99352, United States
| | - Elke Arenholz
- Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Andrew R Felmy
- Pacific Northwest National Laboratory , P.O. Box 999, MS K8-96, Richland, Washington 99352, United States
- Washington State University , Pullman, Washington 99164, United States
| | - Kevin M Rosso
- Pacific Northwest National Laboratory , P.O. Box 999, MS K8-96, Richland, Washington 99352, United States
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Momper L, Jungbluth SP, Lee MD, Amend JP. Energy and carbon metabolisms in a deep terrestrial subsurface fluid microbial community. ISME JOURNAL 2017. [PMID: 28644444 DOI: 10.1038/ismej.2017.94] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The terrestrial deep subsurface is a huge repository of microbial biomass, but in relation to its size and physical heterogeneity, few sites have been investigated in detail. Here, we applied a culture-independent metagenomic approach to characterize the microbial community composition in deep (1500 meters below surface) terrestrial fluids. Samples were collected from a former gold mine in Lead, South Dakota, USA, now Sanford Underground Research Facility (SURF). We reconstructed 74 genomes from metagenomes (MAGs), enabling the identification of common metabolic pathways. Sulfate and nitrate/nitrite reduction were the most common putative energy metabolisms. Complete pathways for autotrophic carbon fixation were found in more than half of the MAGs, with the reductive acetyl-CoA pathway by far the most common. Nearly 40% (29 of 74) of the recovered MAGs belong to bacterial phyla without any cultivated members-microbial dark matter. Three of our MAGs constitute two novel phyla previously only identified in 16 S rRNA gene surveys. The uniqueness of this data set-its physical depth in the terrestrial subsurface, the relative abundance and completeness of microbial dark matter genomes and the overall diversity of this physically deep, dark, community-make it an invaluable addition to our knowledge of deep subsurface microbial ecology.
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Affiliation(s)
- Lily Momper
- Department of Earth, Atmospheric and Planetary Sciences, The Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sean P Jungbluth
- Center for Dark Energy Biosphere Investigations, University of Southern California, Los Angeles, CA, USA.,Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
| | - Michael D Lee
- Department of Biological Sciences, Marine Environmental Biology Section, University of Southern California, Los Angeles, CA, USA
| | - Jan P Amend
- Center for Dark Energy Biosphere Investigations, University of Southern California, Los Angeles, CA, USA.,Department of Biological Sciences, Marine Environmental Biology Section, University of Southern California, Los Angeles, CA, USA.,Department of Earth Sciences, University of Southern California, Los Angeles, CA, USA
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Graham EB, Crump AR, Resch CT, Fansler S, Arntzen E, Kennedy DW, Fredrickson JK, Stegen JC. Deterministic influences exceed dispersal effects on hydrologically-connected microbiomes. Environ Microbiol 2017; 19:1552-1567. [DOI: 10.1111/1462-2920.13720] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 02/08/2017] [Accepted: 03/01/2017] [Indexed: 01/23/2023]
Affiliation(s)
- Emily B. Graham
- Biological Sciences Division, Pacific Northwest National Laboratory; Richland WA USA
| | - Alex R. Crump
- Biological Sciences Division, Pacific Northwest National Laboratory; Richland WA USA
| | - Charles T. Resch
- Geochemistry Department, Pacific Northwest National Laboratory; Richland WA USA
| | - Sarah Fansler
- Biological Sciences Division, Pacific Northwest National Laboratory; Richland WA USA
| | - Evan Arntzen
- Environmental Compliance and Emergency Preparation, Pacific Northwest National Laboratory; Richland WA USA
| | - David W. Kennedy
- Biological Sciences Division, Pacific Northwest National Laboratory; Richland WA USA
| | - Jim K. Fredrickson
- Biological Sciences Division, Pacific Northwest National Laboratory; Richland WA USA
| | - James C. Stegen
- Biological Sciences Division, Pacific Northwest National Laboratory; Richland WA USA
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Rempfert KR, Miller HM, Bompard N, Nothaft D, Matter JM, Kelemen P, Fierer N, Templeton AS. Geological and Geochemical Controls on Subsurface Microbial Life in the Samail Ophiolite, Oman. Front Microbiol 2017; 8:56. [PMID: 28223966 PMCID: PMC5293757 DOI: 10.3389/fmicb.2017.00056] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 01/09/2017] [Indexed: 02/06/2023] Open
Abstract
Microbial abundance and diversity in deep subsurface environments is dependent upon the availability of energy and carbon. However, supplies of oxidants and reductants capable of sustaining life within mafic and ultramafic continental aquifers undergoing low-temperature water-rock reaction are relatively unknown. We conducted an extensive analysis of the geochemistry and microbial communities recovered from fluids sampled from boreholes hosted in peridotite and gabbro in the Tayin block of the Samail Ophiolite in the Sultanate of Oman. The geochemical compositions of subsurface fluids in the ophiolite are highly variable, reflecting differences in host rock composition and the extent of fluid-rock interaction. Principal component analysis of fluid geochemistry and geologic context indicate the presence of at least four fluid types in the Samail Ophiolite (“gabbro,” “alkaline peridotite,” “hyperalkaline peridotite,” and “gabbro/peridotite contact”) that vary strongly in pH and the concentrations of H2, CH4, Ca2+, Mg2+, NO3-, SO42-, trace metals, and DIC. Geochemistry of fluids is strongly correlated with microbial community composition; similar microbial assemblages group according to fluid type. Hyperalkaline fluids exhibit low diversity and are dominated by taxa related to the Deinococcus-Thermus genus Meiothermus, candidate phyla OP1, and the family Thermodesulfovibrionaceae. Gabbro- and alkaline peridotite- aquifers harbor more diverse communities and contain abundant microbial taxa affiliated with Nitrospira, Nitrosospharaceae, OP3, Parvarcheota, and OP1 order Acetothermales. Wells that sit at the contact between gabbro and peridotite host microbial communities distinct from all other fluid types, with an enrichment in betaproteobacterial taxa. Together the taxonomic information and geochemical data suggest that several metabolisms may be operative in subsurface fluids, including methanogenesis, acetogenesis, and fermentation, as well as the oxidation of methane, hydrogen and small molecular weight organic acids utilizing nitrate and sulfate as electron acceptors. Dynamic nitrogen cycling may be especially prevalent in gabbro and alkaline peridotite fluids. These data suggest water-rock reaction, as controlled by lithology and hydrogeology, constrains the distribution of life in terrestrial ophiolites.
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Affiliation(s)
- Kaitlin R Rempfert
- Department of Geological Sciences, University of Colorado Boulder, CO, USA
| | - Hannah M Miller
- Department of Geological Sciences, University of Colorado Boulder, CO, USA
| | - Nicolas Bompard
- National Oceanography Centre, University of Southampton Southampton, UK
| | - Daniel Nothaft
- Department of Geological Sciences, University of Colorado Boulder, CO, USA
| | - Juerg M Matter
- National Oceanography Centre, University of Southampton Southampton, UK
| | - Peter Kelemen
- Lamont-Doherty Earth Observatory, Columbia University Palisades, NY, USA
| | - Noah Fierer
- Cooperate Institute for Research in Environmental Sciences, University of ColoradoBoulder, CO, USA; Department of Ecology and Evolutionary Biology, University of ColoradoBoulder, CO, USA
| | - Alexis S Templeton
- Department of Geological Sciences, University of Colorado Boulder, CO, USA
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Coupling among Microbial Communities, Biogeochemistry, and Mineralogy across Biogeochemical Facies. Sci Rep 2016; 6:30553. [PMID: 27469056 PMCID: PMC4965824 DOI: 10.1038/srep30553] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 03/02/2016] [Indexed: 02/01/2023] Open
Abstract
Physical properties of sediments are commonly used to define subsurface lithofacies and these same physical properties influence subsurface microbial communities. This suggests an (unexploited) opportunity to use the spatial distribution of facies to predict spatial variation in biogeochemically relevant microbial attributes. Here, we characterize three biogeochemical facies-oxidized, reduced, and transition-within one lithofacies and elucidate relationships among facies features and microbial community biomass, richness, and composition. Consistent with previous observations of biogeochemical hotspots at environmental transition zones, we find elevated biomass within a biogeochemical facies that occurred at the transition between oxidized and reduced biogeochemical facies. Microbial richness-the number of microbial taxa-was lower within the reduced facies and was well-explained by a combination of pH and mineralogy. Null modeling revealed that microbial community composition was influenced by ecological selection imposed by redox state and mineralogy, possibly due to effects on nutrient availability or transport. As an illustrative case, we predict microbial biomass concentration across a three-dimensional spatial domain by coupling the spatial distribution of subsurface biogeochemical facies with biomass-facies relationships revealed here. We expect that merging such an approach with hydro-biogeochemical models will provide important constraints on simulated dynamics, thereby reducing uncertainty in model predictions.
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Reitschuler C, Spötl C, Hofmann K, Wagner AO, Illmer P. Archaeal Distribution in Moonmilk Deposits from Alpine Caves and Their Ecophysiological Potential. MICROBIAL ECOLOGY 2016; 71:686-699. [PMID: 26790864 DOI: 10.1007/s00248-015-0727-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 12/27/2015] [Indexed: 06/05/2023]
Abstract
(Alpine) caves are, in general, windows into the Earth's subsurface. Frequently occurring structures in caves such as moonmilk (secondary calcite deposits) offer the opportunity to study intraterrestrial microbial communities, adapted to oligotrophic and cold conditions. This is an important research field regarding the dimensions of subsurface systems and cold regions on Earth. On a methodological level, moonmilk deposits from 11 caves in the Austrian Alps were collected aseptically and investigated using a molecular (qPCR and DGGE sequencing-based) methodology in order to study the occurrence, abundance, and diversity of the prevailing native Archaea community. Furthermore, these Archaea were enriched in complex media and studied regarding their physiology, with a media selection targeting different physiological requirements, e.g. methanogenesis and ammonia oxidation. The investigation of the environmental samples showed that all moonmilk deposits were characterized by the presence of the same few habitat-specific archaeal species, showing high abundances and constituting about 50 % of the total microbial communities. The largest fraction of these Archaea was ammonia-oxidizing Thaumarchaeota, while another abundant group was very distantly related to extremophilic Euryarchaeota (Moonmilk Archaea). The archaeal community showed a depth- and oxygen-dependent stratification. Archaea were much more abundant (around 80 %), compared to bacteria, in the actively forming surface part of moonmilk deposits, decreasing to about 5 % down to the bedrock. Via extensive cultivation efforts, it was possible to enrich the enigmatic Moonmilk Archaea and also AOA significantly above the level of bacteria. The most expedient prerequisites for cultivating Moonmilk Archaea were a cold temperature, oligotrophic conditions, short incubation times, a moonmilk surface inoculum, the application of erythromycin, and anaerobic (microaerophilic) conditions. On a physiological level, it seems that methanogenesis is of marginal importance, while ammonia oxidation and a still undiscovered metabolic pathway are vital elements in the (archaeal) moonmilk biome.
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Affiliation(s)
- Christoph Reitschuler
- Institute of Microbiology, University of Innsbruck, Technikerstrasse 25, A-6020, Innsbruck, Austria.
| | - Christoph Spötl
- Institute of Geology, University of Innsbruck, Innrain 52, A-6020, Innsbruck, Austria
| | - Katrin Hofmann
- Institute of Microbiology, University of Innsbruck, Technikerstrasse 25, A-6020, Innsbruck, Austria
| | - Andreas O Wagner
- Institute of Microbiology, University of Innsbruck, Technikerstrasse 25, A-6020, Innsbruck, Austria
| | - Paul Illmer
- Institute of Microbiology, University of Innsbruck, Technikerstrasse 25, A-6020, Innsbruck, Austria
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Characterization of the prokaryotic diversity through a stratigraphic permafrost core profile from the Qinghai-Tibet Plateau. Extremophiles 2016; 20:337-49. [DOI: 10.1007/s00792-016-0825-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 03/11/2016] [Indexed: 10/22/2022]
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Yan S, Liu Y, Liu C, Shi L, Shang J, Shan H, Zachara J, Fredrickson J, Kennedy D, Resch CT, Thompson C, Fansler S. Nitrate bioreduction in redox-variable low permeability sediments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 539:185-195. [PMID: 26363392 DOI: 10.1016/j.scitotenv.2015.08.122] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Revised: 08/21/2015] [Accepted: 08/21/2015] [Indexed: 06/05/2023]
Abstract
Lowpermeability zone (LPZ) can play an important role as a sink or secondary source in contaminant transport in groundwater system. This study investigated the rate and end product of nitrate bioreduction in LPZ sediments. The sedimentswere fromthe U.S. Department of Energy's Hanford Site,where nitrate is a groundwater contaminant as a by-product of radionuclide waste discharges. The LPZ at the Hanford site consists of two layerswith an oxidized layer on top and reduced layer below. The oxidized layer is directly in contact with the overlying contaminated aquifer, while the reduced layer is in contact with an uncontaminated aquifer below. The experimental results showed that nitrate bioreduction rate and end-product differed significantly in the sediments. The bioreduction rate in the oxidized sediment was significantly faster than that in the reduced one. A significant amount of N2O was accumulated in the reduced sediment; while in the oxidized sediment, N2O was further reduced to N2. RT-PCR analysis revealed that nosZ, the gene that codes for N2O reductase, was below detection limit in the reduced sediment. Batch experiments and kinetic modeling were performed to provide insights into the role of organic carbon bioavailability, biomass growth, and competition between nitrate and its reducing products for electrons fromelectron donors. The results revealed that it is important to consider sediment redox conditions and functional genes in understanding and modeling nitrate bioreduction in subsurface sediments. The results also implied that LPZ sediments can be important sink of nitrate and a potential secondary source of N2O as a nitrate bioreduction product in groundwater.
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Affiliation(s)
- Sen Yan
- China University of Geosciences, Wuhan 430074, China; Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Yuanyuan Liu
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Chongxuan Liu
- China University of Geosciences, Wuhan 430074, China; Pacific Northwest National Laboratory, Richland, WA 99354, USA.
| | - Liang Shi
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Jianying Shang
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Huimei Shan
- China University of Geosciences, Wuhan 430074, China; Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - John Zachara
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Jim Fredrickson
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - David Kennedy
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Charles T Resch
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | | | - Sarah Fansler
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
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Microbiology of the Deep Continental Biosphere. THEIR WORLD: A DIVERSITY OF MICROBIAL ENVIRONMENTS 2016. [DOI: 10.1007/978-3-319-28071-4_6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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43
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Converse BJ, McKinley JP, Resch CT, Roden EE. Microbial mineral colonization across a subsurface redox transition zone. Front Microbiol 2015; 6:858. [PMID: 26379637 PMCID: PMC4551860 DOI: 10.3389/fmicb.2015.00858] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 08/06/2015] [Indexed: 11/13/2022] Open
Abstract
This study employed 16S rRNA gene amplicon pyrosequencing to examine the hypothesis that chemolithotrophic Fe(II)-oxidizing bacteria (FeOB) would preferentially colonize the Fe(II)-bearing mineral biotite compared to quartz sand when the minerals were incubated in situ within a subsurface redox transition zone (RTZ) at the Hanford 300 Area site in Richland, WA, USA. The work was motivated by the recently documented presence of neutral-pH chemolithotrophic FeOB capable of oxidizing structural Fe(II) in primary silicate and secondary phyllosilicate minerals in 300 Area sediments and groundwater (Benzine et al., 2013). Sterilized portions of sand+biotite or sand alone were incubated in situ for 5 months within a multilevel sampling (MLS) apparatus that spanned a ca. 2-m interval across the RTZ in two separate groundwater wells. Parallel MLS measurements of aqueous geochemical species were performed prior to deployment of the minerals. Contrary to expectations, the 16S rRNA gene libraries showed no significant difference in microbial communities that colonized the sand+biotite vs. sand-only deployments. Both mineral-associated and groundwater communities were dominated by heterotrophic taxa, with organisms from the Pseudomonadaceae accounting for up to 70% of all reads from the colonized minerals. These results are consistent with previous results indicating the capacity for heterotrophic metabolism (including anaerobic metabolism below the RTZ) as well as the predominance of heterotrophic taxa within 300 Area sediments and groundwater. Although heterotrophic organisms clearly dominated the colonized minerals, several putative lithotrophic (NH4 (+), H2, Fe(II), and HS(-) oxidizing) taxa were detected in significant abundance above and within the RTZ. Such organisms may play a role in the coupling of anaerobic microbial metabolism to oxidative pathways with attendant impacts on elemental cycling and redox-sensitive contaminant behavior in the vicinity of the RTZ.
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Affiliation(s)
| | | | | | - Eric E. Roden
- Department of Geoscience, University of Wisconsin-MadisonMadison, WI, USA
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Nelson WC, Stegen JC. The reduced genomes of Parcubacteria (OD1) contain signatures of a symbiotic lifestyle. Front Microbiol 2015; 6:713. [PMID: 26257709 PMCID: PMC4508563 DOI: 10.3389/fmicb.2015.00713] [Citation(s) in RCA: 181] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 06/29/2015] [Indexed: 11/21/2022] Open
Abstract
Candidate phylum OD1 bacteria (also referred to as Parcubacteria) have been identified in a broad range of anoxic environments through community survey analysis. Although none of these species have been isolated in the laboratory, several genome sequences have been reconstructed from metagenomic sequence data and single-cell sequencing. The organisms have small (generally <1 Mb) genomes with severely reduced metabolic capabilities. We have reconstructed 8 partial to near-complete OD1 genomes from oxic groundwater samples, and compared them against existing genomic data. The conserved core gene set comprises 202 genes, or ~28% of the genomic complement. “Housekeeping” genes and genes for biosynthesis of peptidoglycan and Type IV pilus production are conserved. Gene sets for biosynthesis of cofactors, amino acids, nucleotides, and fatty acids are absent entirely or greatly reduced. The only aspects of energy metabolism conserved are the non-oxidative branch of the pentose-phosphate shunt and central glycolysis. These organisms also lack some activities conserved in almost all other known bacterial genomes, including signal recognition particle, pseudouridine synthase A, and FAD synthase. Pan-genome analysis indicates a broad genotypic diversity and perhaps a highly fluid gene complement, indicating historical adaptation to a wide range of growth environments and a high degree of specialization. The genomes were examined for signatures suggesting either a free-living, streamlined lifestyle, or a symbiotic lifestyle. The lack of biosynthetic capabilities and DNA repair, along with the presence of potential attachment and adhesion proteins suggest that the Parcubacteria are ectosymbionts or parasites of other organisms. The wide diversity of genes that potentially mediate cell-cell contact suggests a broad range of partner/prey organisms across the phylum.
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Affiliation(s)
- William C Nelson
- Microbiology, Biological Sciences Division, Pacific Northwest National Laboratory Richland, WA, USA
| | - James C Stegen
- Microbiology, Biological Sciences Division, Pacific Northwest National Laboratory Richland, WA, USA
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Microbially influenced corrosion communities associated with fuel-grade ethanol environments. Appl Microbiol Biotechnol 2015; 99:6945-57. [PMID: 26092755 PMCID: PMC4513208 DOI: 10.1007/s00253-015-6729-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 05/23/2015] [Accepted: 05/26/2015] [Indexed: 01/02/2023]
Abstract
Microbially influenced corrosion (MIC) is a costly problem that impacts hydrocarbon production and processing equipment, water distribution systems, ships, railcars, and other types of metallic infrastructure. In particular, MIC is known to cause considerable damage to hydrocarbon fuel infrastructure including production, transportation, and storage systems, often times with catastrophic environmental contamination results. As the production and use of alternative fuels such as fuel-grade ethanol (FGE) increase, it is important to consider MIC of engineered materials exposed to these “newer fuels” as they enter existing infrastructure. Reports of suspected MIC in systems handling FGE and water prompted an investigation of the microbial diversity associated with these environments. Small subunit ribosomal RNA gene pyrosequencing surveys indicate that acetic-acid-producing bacteria (Acetobacter spp. and Gluconacetobacter spp.) are prevalent in environments exposed to FGE and water. Other microbes previously implicated in corrosion, such as sulfate-reducing bacteria and methanogens, were also identified. In addition, acetic-acid-producing microbes and sulfate-reducing microbes were cultivated from sampled environments containing FGE and water. Results indicate that complex microbial communities form in these FGE environments and could cause significant MIC-related damage that may be difficult to control. How to better manage these microbial communities will be a defining aspect of improving mitigation of global infrastructure corrosion.
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Lee JH, Fredrickson JK, Plymale AE, Dohnalkova AC, Resch CT, McKinley JP, Shi L. An autotrophic H2 -oxidizing, nitrate-respiring, Tc(VII)-reducing Acidovorax sp. isolated from a subsurface oxic-anoxic transition zone. ENVIRONMENTAL MICROBIOLOGY REPORTS 2015; 7:395-403. [PMID: 25558059 DOI: 10.1111/1758-2229.12263] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 12/19/2014] [Indexed: 06/04/2023]
Abstract
Increasing concentrations of H2 with depth were observed across a geologic unconformity and associated redox transition zone in the subsurface at the Hanford Site in south-central Washington, USA. An opposing gradient characterized by decreasing O2 and nitrate concentrations was consistent with microbial-catalysed biogeochemical processes. Sterile sand was incubated in situ within a multilevel sampler placed across the redox transition zone to evaluate the potential for Tc(VII) reduction and for enrichment of H2 -oxidizing denitrifiers capable of reducing Tc(VII). H2 -driven TcO4 (-) reduction was detected in sand incubated at all depths but was strongest in material from a depth of 17.1 m. Acidovorax spp. were isolated from H2 -nitrate enrichments from colonized sand from 15.1 m, with one representative, strain JHL-9, subsequently characterized. JHL-9 grew on acetate with either O2 or nitrate as electron acceptor (data not shown) and on medium with bicarbonate, H2 and nitrate. JHL-9 also reduced pertechnetate (TcO4 (-) ) under denitrifying conditions with H2 as the electron donor. H2 -oxidizing Acidovorax spp. in the subsurface at Hanford and other locations may contribute to the maintenance of subsurface redox gradients and offer the potential for Tc(VII) reduction.
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Affiliation(s)
- Ji-Hoon Lee
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | | | | | | | - Charles T Resch
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | | | - Liang Shi
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
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Bräuer S, Cadillo-Quiroz H, Kyrpides N, Woyke T, Goodwin L, Detter C, Podell S, Yavitt JB, Zinder SH. Genome of Methanoregula boonei 6A8 reveals adaptations to oligotrophic peatland environments. MICROBIOLOGY-SGM 2015; 161:1572-1581. [PMID: 25998264 DOI: 10.1099/mic.0.000117] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Analysis of the genome sequence of Methanoregula boonei strain 6A8, an acidophilic methanogen isolated from an ombrotrophic (rain-fed) peat bog, has revealed unique features that likely allow it to survive in acidic, nutrient-poor conditions. First, M. boonei is predicted to generate ATP using protons that are abundant in peat, rather than sodium ions that are scarce, and the sequence of a membrane-bound methyltransferase, believed to pump Na+ in all methanogens, shows differences in key amino acid residues. Further, perhaps reflecting the hypokalemic status of many peat bogs, M. boonei demonstrates redundancy in the predicted potassium uptake genes trk, kdp and kup, some of which may have been horizontally transferred to methanogens from bacteria, possibly Geobacter spp. Overall, the putative functions of the potassium uptake, ATPase and methyltransferase genes may, at least in part, explain the cosmopolitan success of group E1/E2 and related methanogenic archaea in acidic peat bogs.
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Affiliation(s)
- Suzanna Bräuer
- Department of Biology, Appalachian State University, Boone, NC 28608, USA
| | - Hinsby Cadillo-Quiroz
- Swette Center for Environmental Biotechnology at the Biodesign Institute, Arizona State University, Tempe, AZ 85287-4501, USA
| | - Nikos Kyrpides
- Department of Energy, Joint Genome Institute, Walnut Creek, CA 94598, USA
| | - Tanja Woyke
- Department of Energy, Joint Genome Institute, Walnut Creek, CA 94598, USA
| | - Lynne Goodwin
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Chris Detter
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Sheila Podell
- Scripps Institution of Oceanography, La Jolla, CA 92093, USA
| | - Joseph B Yavitt
- Department of Natural Resources, Cornell University, Ithaca, NY 14853, USA
| | - Stephen H Zinder
- Department of Microbiology, Cornell University, Ithaca, NY 14853, USA
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49
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Prokaryotic community structure in deep bedrock aquifers of the Austrian Central Alps. Antonie van Leeuwenhoek 2014; 107:687-701. [DOI: 10.1007/s10482-014-0363-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 12/16/2014] [Indexed: 10/24/2022]
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50
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Kurt Z, Mack EE, Spain JC. Biodegradation of cis-dichloroethene and vinyl chloride in the capillary fringe. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:13350-13357. [PMID: 25329424 DOI: 10.1021/es503071m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Volatile chlorinated compounds are major pollutants in groundwater, and they pose a risk of vapor intrusion into buildings. Vapor intrusion can be prevented by natural attenuation in the vadose zone if biodegradation mechanisms can be established. In this study, we tested the hypothesis that bacteria can use cis-dichloroethene (cis-DCE) or vinyl chloride (VC) as an electron donor in the vadose zone. Anoxic water containing cis-DCE or VC was pumped continuously beneath laboratory columns that represented the vadose zone. Columns were inoculated with Polaromonas sp. strain JS666, which grows aerobically on cis-DCE, or with Mycobacterium sp. JS60 and Nocardiodes sp. JS614 that grow on VC. Complete biodegradation with fluxes of 84 ± 15 μmol of cis-DCE · m(-2) · hr(-1) and 218 ± 25 μmole VC·m(-2) · h(-1) within the 23 cm column indicated that microbial activities can prevent the migration of cis-DCE and VC vapors. Oxygen and volatile compound profiles along with enumeration of bacterial populations indicated that most of the biodegradation took place in the first 10 cm above the saturated zone within the capillary fringe. The results revealed that cis-DCE and VC can be biodegraded readily at the oxic/anoxic interfaces in the vadose zone if appropriate microbes are present.
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Affiliation(s)
- Zohre Kurt
- School of Civil and Environmental Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332-0512, United States
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