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Denise M Akob, Ph.D.

Denise Akob is a Research Microbiologist for the USGS Geology, Energy & Minerals (GEM) Science Center in Reston, VA.

Dr. Denise M. Akob is a microbial ecologist and biogeochemist whose research aims to understand interactions between microbes and their environment in order to solve anthropogenic issues. Her research focuses primarily on understanding microbial impacts on Cold War Biogeochemistry (uranium and chlorinated solvent contamination); energy production (either by mitigating degradation of contaminants (from hydraulic fracturing or oil spills) or by enhancing natural gas production); and carbon cycling. Dr. Akob joined the U.S. Geological Survey in 2012 as a research scientist in the Water Mission Area, and move to the Geology, Energy, and Minerals Science Center in 2020. For more information, please visit the Reston Microbiology Lab website.

Education

  • Ph.D. 2008, Florida State University, Department of Oceanography, Advisor: Dr. Joel E. Kostka
  • B.A. 2002, St. Mary’s College of Maryland, Major: Biology

Work Experience

  • Affiliated Professor, Department of Biology at George Mason University, 2017-current.
  • Affiliated Professor, Department of Geology, Appalachian State University, 2017- present.
  • Adjunct Graduate Faculty, University of Alabama, Department of Biological Sciences, 2016-present.
  • Affiliated Professor, Department of Geography and Planning, Appalachian State University, 2016-current.
  • Affiliated Professor, Environmental Science and Policy Department at George Mason University, 2013-current.
  • Research Microbiologist, U.S. Geological Survey, Water Mission Area, Reston Microbiology Laboratory. 2012-current
  • Postdoctoral Research Fellow, Friedrich-Schiller University Jena. 2010-2012
  • Marie Curie Postdoctoral Research Fellow, Friedrich-Schiller University Jena. 2008-2010

Professional Affiliations or Activities 

  • Associate Editor, Biogeosciences, 2016-present.
  • Editorial Board Member, FEMS Microbiology Ecology, 2016-present.
  • Editorial Board Member, Applied and Environmental Microbiology, January 1, 2018- December 31, 2020.
  • President, Washington, D.C. Branch of the American Society for Microbiology, 2019-present.
  • President-Elect, Washington, D.C. Branch of the American Society for Microbiology, 2017-2019.
  • USGS Community for Data Integration’s Bioinformatics Community of Practice, co-organizer, 2017-present.
  • USGS Eastern Water Science Series, co-organizer, 2017-present.
  • Applied and Environmental Microbiology Gordon Research Seminar Mentor, July 15-16, 2017.
  • USGS NRP-EB Weekly Science Series, co-organizer (2013-2017)
  • Geobiology Theme Chair, Goldschmidt 2015 25th Anniversary Meeting
  • Co-Chair for Session T50. Microbial Hydrocarbon Formation and Biodegradation: Organisms, Pathways, Environmental Limitations, and Isotope Signatures, 2015 Geological Society of America Annual Meeting, Baltimore, MD

Awards

  • USGS Early Career Leadership Award, 2017

Science and Products

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Framework for Examining Stream Ecosystem Health in Areas of Shale Gas Development—A Multi-Parameter Watershed-Based Case Study in Pennsylvania

In a case study of 25 headwater streams in Pennsylvania, no statistically significant associations were determined between shale gas development and geochemical tracers of produced waters or measures of microbial and macroinvertebrate community composition. Although the results are specific to the region studied, the integrated biological and geochemical framework provides a tool for examining...
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Ecosystems, Contaminant Biology, Toxic Substances Hydrology, Environmental Health Program
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Framework for Examining Stream Ecosystem Health in Areas of Shale Gas Development—A Multi-Parameter Watershed-Based Case Study in Pennsylvania

In a case study of 25 headwater streams in Pennsylvania, no statistically significant associations were determined between shale gas development and geochemical tracers of produced waters or measures of microbial and macroinvertebrate community composition. Although the results are specific to the region studied, the integrated biological and geochemical framework provides a tool for examining...
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Picture of oil and gas development and associated activities along with wetlands in the Prairie Pothole Region..

Energy Integrated Science Team

The Energy Lifecycle Integrated Science Team focuses on the potential for contaminant exposures in the environment that might originate from energy resource activities including, extraction, production, transportation, storage, extraction, waste management and restoration. Perceived health risks to humans and other organisms will be distinguished from actual risks, if any. If actual risks are...
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Ecosystems, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology
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Energy Integrated Science Team

The Energy Lifecycle Integrated Science Team focuses on the potential for contaminant exposures in the environment that might originate from energy resource activities including, extraction, production, transportation, storage, extraction, waste management and restoration. Perceived health risks to humans and other organisms will be distinguished from actual risks, if any. If actual risks are...
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Dr. Denise Akob giving a laboratory tour

Two Scientists Receive Early Career Excellence in Leadership Award

The U.S. Geological Survey (USGS) 2016 Early Career Excellence in Leadership Award was given to Dr. Denise M. Akob and Dr. Karl B. Haase. Drs. Akob and Haase have demonstrated outstanding leadership through their scientific accomplishments and service to the USGS.
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Ecosystems, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, Reston Microbiology Laboratory
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Two Scientists Receive Early Career Excellence in Leadership Award

The U.S. Geological Survey (USGS) 2016 Early Career Excellence in Leadership Award was given to Dr. Denise M. Akob and Dr. Karl B. Haase. Drs. Akob and Haase have demonstrated outstanding leadership through their scientific accomplishments and service to the USGS.
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USGS scientist collecting water samples on a wastewater disposal facility

Trace Levels of Organic Chemicals Limited to Local Reaches of a Stream near an Oil and Gas Wastewater Disposal Facility

Organic contaminants that were present in Wolf Creek near a wastewater disposal facility were not evident farther downstream where Wolf Creek enters the New River. Wolf Creek and the New River are used for drinking water and recreational purposes.
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Ecosystems, Contaminant Biology, Energy Resources Program, Environmental Health Program, Toxic Substances Hydrology
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Trace Levels of Organic Chemicals Limited to Local Reaches of a Stream near an Oil and Gas Wastewater Disposal Facility

Organic contaminants that were present in Wolf Creek near a wastewater disposal facility were not evident farther downstream where Wolf Creek enters the New River. Wolf Creek and the New River are used for drinking water and recreational purposes.
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USGS scientist collecting water samples on a wastewater disposal facility

Examining Shifts in Stream Microbial Communities Exposed to Oil and Gas Wastewaters

Shifts in the overall microbial community structure were present in stream sediments that contained chemicals associated with unconventional oil and gas wastewaters. This work is part of a long-term study designed to understand persistence of chemicals from oil and gas wastewaters in sediments and water and how those factors might be related to exposures and adverse health effects, if any, on...
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Ecosystems, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology
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Examining Shifts in Stream Microbial Communities Exposed to Oil and Gas Wastewaters

Shifts in the overall microbial community structure were present in stream sediments that contained chemicals associated with unconventional oil and gas wastewaters. This work is part of a long-term study designed to understand persistence of chemicals from oil and gas wastewaters in sediments and water and how those factors might be related to exposures and adverse health effects, if any, on...
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Tanker truck sits in from of several large tanks holding wastewater.

Indication of Unconventional Oil and Gas Wastewaters Found in Local Surface Waters

Evidence indicating the presence of wastewaters from unconventional oil and gas (UOG) production was found in surface waters and surficial sediments near an UOG disposal facility in West Virginia.
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Ecosystems, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology
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Indication of Unconventional Oil and Gas Wastewaters Found in Local Surface Waters

Evidence indicating the presence of wastewaters from unconventional oil and gas (UOG) production was found in surface waters and surficial sediments near an UOG disposal facility in West Virginia.
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Anaerobic microbial cultures from shale gas production waters

Microbiology and Chemistry of Waters Produced from Hydraulic Fracking—A Case Study

A new U.S. Geological Survey (USGS) study determined that the microbiology and organic chemistry of produced waters varied widely among hydraulically fractured shale gas wells in north-central Pennsylvania.
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Ecosystems, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology
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Microbiology and Chemistry of Waters Produced from Hydraulic Fracking—A Case Study

A new U.S. Geological Survey (USGS) study determined that the microbiology and organic chemistry of produced waters varied widely among hydraulically fractured shale gas wells in north-central Pennsylvania.
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Microbial Community Composition Data from Blacktail Creek near Williston, North Dakota

A large spill of wastewater from oil and gas operations was discovered adjacent to Blacktail Creek near Williston, North Dakota in January 2015. To determine the effects of this spill on streambed microbial communities over time, bed sediment samples were taken from Blacktail Creek upstream, adjacent to, and at several locations downstream from the spill site. Blacktail Creek is a tributary of the

Data on the Effects of Oil and Gas Wastewater Components on Microbial Community Structure and Function

Oil and gas (OG) wastewaters are commonly disposed of by underground injection and previous research showed that activities at a disposal facility in West Virginia affected stream biogeochemistry and sediment microbial communities downstream from the facility. Microorganisms can control the fate and transport of organic and inorganic components of OG wastewater highlighting the need to characteriz
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Energy Resources Program, Geology, Energy & Minerals Science Center

Data on the Enrichment and Isolation of the Acetylenotrophic and Diazotrophic Isolate Bradyrhizobium sp. strain I71

Acetylene (C2H2) is a molecule rarely found in nature, with few known natural sources, but acetylenotrophic microorganisms can use acetylene as their primary carbon and energy source. As of 2018 there were 15 known strains of aerobic and anaerobic acetylenotrophs, however we hypothesized that there may be yet unrecognized diversity of acetylenotrophs in nature. In this study, we expanded this dive
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Geology, Energy & Minerals Science Center

Acetylene Consumption and Dechlorination by a Groundwater Microbial Enrichment Culture

This study aimed to (1) enrich microbial acetylenotrophs from trichloroethylene (TCE) contaminated groundwater and (2) evaluate whether these enrichments could degrade TCE coupled to acetylene degradation. Acetylenotrophs are microorganisms that use acetylene as their carbon and energy source. TCE contaminated groundwater was collected from wells at the Naval Air Warfare Center (NAWC) in West Tren
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Water Resources

Chemistry of waters collected in the Wolf Creek and Buffalo Creek watersheds in West Virginia in 2016

Water chemistry data for samples collected in 2016 in the Wolf Creek and Buffalo Creek watersheds in West Virginia. The dataset includes stream characteristics including flow and location information for sampling sites.
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Water Resources

Current-use pesticides and emerging amphibian pathogens in natural ponds, excavated ponds, and stormwater basins from 24 sites varying in land-use classifications throughout the New Jersey Pinelands, 2014-2016

Water, sediment, anuran food (leaf litter and detritus) and whole body larval amphibian composites were analyzed for over 100 current-use pesticides from 24 wetlands representing land-use gradients in the New Jersey Pinelands, USA during 2014-2016. Emerging amphibian pathogens, Ranavirus and Batrachochytrium dendrobatidis (Bd) were also assessed in individual larvae at the 24 wetlands. Tables in t
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New Jersey Water Science Center

Microbiology of the greater Bravo Dome region

Bravo Dome is a commercial natural CO2 field that supplies the gas to depleted oil fields for enhanced oil recovery. In order to understand the distribution of CO2 across the greater Bravo Dome region, including southeastern Colorado and northwestern New Mexico, and to assess the impacts of high CO2 concentrations on microbes in the subsurface, 7 samples were collected from sites associated with h
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Energy Resources Program, Geology, Energy & Minerals Science Center

MCHM Degradation Data Release

This USGS data release includes all the data presented in peer-reviewed publication entitled "Degradation of MCHM (4-methylcyclohexanemethanol) in Sediments from Elk River, West Virginia". We conducted experiments on crude MCHM to examine photooxidation or biodegradation. We also assessed the potential of sediments to serve as a long-term source of MCHM and well as the potential for native microb
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Water Resources, Reston Biogeochemical Processes in Groundwater Laboratory
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Complete genome sequence of Rhodococcus opacus strain MoAcy1 (DSM 44186), an aerobic acetylenotroph isolated from soil

We report the genome of Rhodococcus opacus strain MoAcy1 (DSM 44186), an aerobic soil isolate capable of using acetylene as its primary carbon and energy source (acetylenotrophy). The genome is composed of a single circular chromosome of ∼8 Mbp and two closed plasmids, with a G+C content of 67.3%.
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Toxic Substances Hydrology, Geology, Energy & Minerals Science Center, Reston Microbiology Laboratory

Oil and gas wastewater components alter streambed microbial community structure and function

The widespread application of directional drilling and hydraulic fracturing technologies expanded oil and gas (OG) development to previously inaccessible resources. A single OG well can generate millions of liters of wastewater, which is a mixture of brine produced from the fractured formations and injected hydraulic fracturing fluids (HFFs). With thousands of wells completed each year, safe manag
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Energy Resources Program, Toxic Substances Hydrology, Geology, Energy & Minerals Science Center, Reston Microbiology Laboratory

Draft genome sequence of Bordetella sp. strain FB-8, isolated from a former uranium mining area in Germany

Here, we present the draft genome sequence of Bordetella sp. strain FB-8, a mixotrophic iron-oxidizing bacterium isolated from creek sediment in the former uranium-mining district of Ronneburg, Germany. To date, iron oxidation has not been reported in Bordetella species, indicating that FB-8 may be an environmentally important Bordetella sp.
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Water Resources, Geology, Energy & Minerals Science Center, Reston Microbiology Laboratory

Syntrophotalea acetylenivorans sp. nov., a diazotrophic, acetylenotrophic anaerobe isolated from intertidal sediments

A Gram-stain-negative, strictly anaerobic, non-motile, rod-shaped bacterium, designated SFB93T, was isolated from the intertidal sediments of South San Francisco Bay, located near Palo Alto, CA, USA. SFB93T was capable of acetylenotrophic and diazotrophic growth, grew at 22–37 °C, pH 6.3–8.5 and in the presence of 10–45 g l−1 NaCl. Phylogenetic analyses based on 16S rRNA gene sequencing showed tha
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Water Resources, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, Earth Resources Observation and Science (EROS) Center , Geology, Energy & Minerals Science Center

Acetylene-fueled trichloroethene reductive dechlorination in a groundwater enrichment culture

In aquifers, acetylene (C2H2) is a product of abiotic degradation of trichloroethene (TCE) catalyzed by in situ minerals. C2H2 can, in turn, inhibit multiple microbial processes including TCE dechlorination and metabolisms that commonly support dechlorination, in addition to supporting the growth of acetylenotrophic microorganisms. Previously, C2H2 was shown to support TCE reductive dechlorination
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Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, Reston Microbiology Laboratory

Mixotrophic iron-oxidizing Thiomonas isolates from an acid mine drainage-affected creek

Natural attenuation of heavy metals occurs via coupled microbial iron cycling and metal precipitation in creeks impacted by acid mine drainage (AMD). Here, we describe the isolation, characterization, and genomic sequencing of two iron-oxidizing bacteria (FeOB) species: Thiomonas ferrovorans FB-6 and Thiomonas metallidurans FB-Cd, isolated from slightly acidic (pH 6.3), Fe-rich, AMD-impacted creek
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Reston Microbiology Laboratory

Geochemical and geophysical indicators of oil and gas wastewater can trace potential exposure pathways following releases to surface waters

Releases of oil and gas (OG) wastewaters can have complex effects on stream-water quality and downstream organisms, due to sediment-water interactions and groundwater/surface water exchange. Previously, elevated concentrations of sodium (Na), chloride (Cl), barium (Ba), strontium (Sr), and lithium (Li), and trace hydrocarbons were determined to be key markers of OG wastewater releases when combine
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Water Resources, Energy Resources Program, Reston Biogeochemical Processes in Groundwater Laboratory, Reston Microbiology Laboratory

Compositional analysis of formation water geochemistry and microbiology of commercial and carbon dioxide-rich wells in the southwestern United States

Studies of naturally occurring subsurface carbon dioxide (CO2) accumulations can provide useful information for potential CO2 injection projects; however, the microbial communities and formation water geochemistry of most reservoirs are understudied. Formation water and microbial biomass were sampled at four CO2-rich reservoir sites: two within Bravo Dome, a commercial CO2 field in New Mexico; one
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Energy Resources Program, Geology, Energy & Minerals Science Center, Reston Microbiology Laboratory

Shale gas development has limited effects on stream biology and geochemistry in a gradient-based, multiparameter study in Pennsylvania

The number of horizontally drilled shale oil and gas wells in the United States has increased from nearly 28,000 in 2007 to nearly 127,000 in 2017, and research has suggested the potential for the development of shale resources to affect nearby stream ecosystems. However, the ability to generalize current studies is limited by the small geographic scope as well as limited breadth and integration o
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Water Resources, Energy & Wildlife, Pennsylvania Water Science Center, Reston Biogeochemical Processes in Groundwater Laboratory, Reston Microbiology Laboratory

Binning singletons: Mentoring through networking at ASM microbe 2019

The American Society for Microbiology (ASM) national conference, Microbe, is the flagship meeting for microbiologists across the globe. The presence of roughly 10,000 attendees provides enormous opportunities for networking and learning. However, such a large meeting can be intimidating to many, especially early career scientists, students, those attending alone, and those from historically underr
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Water Resources, Reston Microbiology Laboratory

Draft genome sequence of the Mn(II)-oxidizing bacterium Oxalobacteraceae sp. AB_14

Biological Mn(II) oxidation produces reactive manganese oxides that help to mitigate metal contamination in the environment. Here we present the genome of Oxalobacteraceae sp. AB_14, a species of Mn(II)-oxidizing bacteria (MOB) notable for its ability to catalyze Mn oxidation at low pH (5.5).
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Water Resources, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, Reston Microbiology Laboratory

Phylogenetic techniques in geomicrobiology

Molecular biological techniques have revolutionized the field of geomicrobiology by providing researchers with robust techniques for identifying microorganisms and characterizing microbial communities in a wide variety of environments. These techniques have freed researchers from the constraints of classical culture-based microbiology and allowed the discovery of previously unknown phylogenetic di
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Water Resources, Reston Microbiology Laboratory

Pre-USGS Publications

Keiner, R., A. Rusznyak, D. M. Akob, S. Hanf, K. Küsel, J. Popp, and T. Frosch. 2013. Raman spectroscopy – an innovative and versatile tool to follow the respirational activity and carbonate biomineralization of important cave bacteria. Analytical Chemistry, 85(18): 8708–8714 (DOI: 10.1021/ac401699d).
Gray, S. M., D. M. Akob, S. J. Green, and J. E. Kostka. 2012. The predictability of bacterial composition within the Sarracenia purpurea model system: local scale differences and relationships with the other members of the food web. PLoS One 7(12): e50969.
Akob, D. M.*, S. H. Lee*, M. Sheth, K. Küsel, D. B. Watson, A.V. Palumbo, J.E. Kostka, and K.-J. Chin. 2012. Gene expression correlates with process rates quantified for sulfate- and Fe(III)-reducing bacteria in U(VI)-contaminated sediments. Frontiers in Terrestrial Microbiology, 3:280. *Equal contribution.
Risse-Buhl, U., M. Herrmann, D. M. Akob, P. Geesink, N. Pizani, W. Schönborn, K.-U. Totsche and K. Küsel. 2012 Phagotrophic protist diversity in the groundwater of a karstic aquifer - morphological and molecular analysis. Journal of Eukaryotic Microbiology, 60(5): 467–479 (DOI: 10.1111/jeu.12054.
Rusznyák, A., D. M. Akob, S. Nietzsche, K. Eusterhues, K. U. Totsche, T. R. Neu, T. Frosch, J. Popp, R. Keiner, J. Geletneky, L. Katzschmann, E.-D. Schulze, and K. Küsel. 2012. Calcite biomineralization by bacterial isolates from the recently discovered pristine karstic Herrenberg Cave. Applied and Environmental Microbiology 78(4): 1157–1167.
Akob, D. M. and K. Küsel. 2011. Where microorganisms meet rocks in the Earth's Critical Zone. Biogeosciences 8, 3531-3543.
Akob, D. M., L. Kerkhof, K. Küsel, D. B. Watson, A. V. Palumbo, and J. E. Kostka. 2011. Linking specific heterotrophic bacterial populations to bioreduction of uranium and nitrate using stable isotope probing in contaminated subsurface sediments. Applied and Environmental Microbiology. 77(22):8197-8200
Burkhardt, E.-M., S. Bischoff, D. M. Akob, G. Büchel, and K. Küsel. 2011. Heavy metal tolerance of Fe(III)-reducing microbial communities in a contaminated creek bank soil. Applied and Environmental Microbiology 77(9): 3132-3136.
Lu, S., S. Gischkat, M. Reiche, D. M. Akob, K. B. Hallberg, and K. Küsel. 2010. Ecophysiology of Fe-cycling Bacteria in Acidic Sediments. Applied and Environmental Microbiology 76 (24): 8174-8183.
Vishnivetskaya, T. A., C. C. Brandt, A. S. Madden, M. S. Drake, J. E. Kostka, D. M. Akob, K. Küsel, and A. V. Palumbo. 2010. Microbial Community Changes in Response to Ethanol or Methanol Amendments for U(VI) Reduction. Applied and Environmental Microbiology 76(17): 5728-5735.
Sitte, J., D. M. Akob, C. Kaufmann, K. Finster, D. Banerjee, E.-M. Burkhardt, J. E. Kostka, A. Scheinost, Georg Büchel and K. Küsel. 2010. Microbial Links between Sulfate Reduction and Metal Retention in Uranium and Heavy Metal-contaminated Soil. Applied and Environmental Microbiology 76(10): 3143–3152.
Green, S. J., O. Prakash, T. M. Gihring, D. M. Akob, P. Jasrotia, P. M. Jardine, D. B. Watson, S. D. Brown, A. V. Palumbo and J. E. Kostka. 2010. Denitrifying bacteria from the terrestrial subsurface exposed to mixed waste contamination. Applied and Environmental Microbiology 76(10): 3244–3254.
Burkhardt, E.-M., D. M. Akob, S. Bischoff, J. Sitte, J. E. Kostka, D. Banerjee, A. C. Scheinost, K. Küsel. 2010. Impact of Biostimulated Redox Processes on Metal Dynamics in an Iron-rich Creek Soil of a former Uranium Mining Area. Environmental Science & Technology 44(1): 177-183.
O. Prakash, T.M. Gihring, D.D. Dalton, K.-J. Chin, S.J. Green, D.M. Akob, G. Wanger, J.E. Kostka. 2010. Geobacter daltonii sp. nov., an iron(III)- and uranium(VI)-reducing bacterium isolated from the shallow subsurface exposed to mixed heavy metal and hydrocarbon contamination. International Journal of Systematic and Evolutionary Microbiology 60: 546-553.
D. M. Akob, H. J. Mills, T. M. Gihring, L. Kerkhof, J. W. Stucki, Kuk-Jeong Chin, Kirsten Kuesel, Anthony V. Palumbo, David B. Watson, and Joel E. Kostka. 2008. Functional diversity and electron donor dependence of microbial populations capable of U(VI) reduction in radionuclide contaminated subsurface sediments. Applied and Environmental Microbiology 74: 3159-3170.
Blöthe, M., D.M. Akob, K. Walter, J.E. Kostka, H.L. Drake, and K. Küsel. 2008. Heterogeneity of Fe(III)-reducing microorganisms in coal-mining lake sediments caused by a pH gradient. Applied and Environmental Microbiology 74(4): 1019–102.
D. M. Akob, H. J. Mills, D. L. Swofford, J. E. Kostka. 2007. Metabolically-Active Microbial Communities in Uranium-Contaminated Subsurface Sediments. FEMS Microbiology Ecology 59: 95-107.
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Evidence of Unconventional Oil and Gas Wastewater Found in Surface Waters near Underground Injection Site

These are the first published studies to demonstrate water-quality impacts to a surface stream due to activities at an unconventional oil and gas...

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The Chemistry of Waters that Follow from Fracking: A Case Study

In a study of 13 hydraulically fractured shale gas wells in north-central Pennsylvania, USGS researchers found that the microbiology and organic...
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