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Khare D, Acharya C. Uranium biomineralization by immobilized Chryseobacterium sp. strain PMSZPI cells for efficient uranium removal. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133503. [PMID: 38228007 DOI: 10.1016/j.jhazmat.2024.133503] [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: 10/01/2023] [Revised: 12/05/2023] [Accepted: 01/09/2024] [Indexed: 01/18/2024]
Abstract
Uranium (U) contamination is hazardous to human health and the environment owing to its radiotoxicity and chemical toxicity and needs immediate attention. In this study, the immobilized biomass of Chryseobacterium sp. strain PMSZPI isolated from U enriched site, was investigated for U(VI) biomineralization in batch and column set-up. Under batch mode, the fresh or lyophilized cells successfully entrapped in calcium alginate beads demonstrated effectual U precipitation under acid and alkaline conditions. The maximum removal was detected at pH 7 wherein ∼98-99% of uranium was precipitated from 1 mM uranyl carbonate solution loading ∼350 mg U/g of biomass within 24 h in the presence of organic phosphate substrate. The resulting uranyl phosphate precipitates within immobilized biomass loaded beads were observed by SEM-EDX and TEM while the formation of U biomineral was confirmed by FTIR and XRD. Retention of phosphatase activity without any loss of uranium precipitation ability was observed for alginate beads with lyophilized biomass stored for 90 d at 4 °C. Continuous flow through experiment with PMSZPI biomass immobilized in polyacrylamide gel exhibited U loading of 0.8 g U/g of biomass at pH 7 using 1 l of 1 mM uranyl solution. This investigation established the feasibility for the application of immobilized PMSZPI biomass for field studies. ENVIRONMENTAL IMPLICATION: Uranium contamination is currently a serious environmental concern owing to anthropogenic activities and needs immediate attention. We have developed here a biotechnological method for successful uranium removal using immobilized cells of a uranium tolerant environmental bacterium, Chryseobacterium sp. strain PMSZPI isolated from U ore deposit via phosphatase enzyme mediated uranium precipitation. The ability of immobilized PMSZPI cells to precipitate U(VI) as long-term stable U phosphates under environmental conditions relevant for contaminated waters containing high concentrations of U that exerts toxicity for biological systems is explored here. The long term stability of the immobilized biomass without compromising its U removal capacity shows the relevance of the bioremediation strategy for uranium contamination proposed in this work.
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Affiliation(s)
- Devanshi Khare
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, India
| | - Celin Acharya
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, India.
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2
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Ning D, Wang Y, Fan Y, Wang J, Van Nostrand JD, Wu L, Zhang P, Curtis DJ, Tian R, Lui L, Hazen TC, Alm EJ, Fields MW, Poole F, Adams MWW, Chakraborty R, Stahl DA, Adams PD, Arkin AP, He Z, Zhou J. Environmental stress mediates groundwater microbial community assembly. Nat Microbiol 2024; 9:490-501. [PMID: 38212658 DOI: 10.1038/s41564-023-01573-x] [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: 03/22/2023] [Accepted: 11/28/2023] [Indexed: 01/13/2024]
Abstract
Community assembly describes how different ecological processes shape microbial community composition and structure. How environmental factors impact community assembly remains elusive. Here we sampled microbial communities and >200 biogeochemical variables in groundwater at the Oak Ridge Field Research Center, a former nuclear waste disposal site, and developed a theoretical framework to conceptualize the relationships between community assembly processes and environmental stresses. We found that stochastic assembly processes were critical (>60% on average) in shaping community structure, but their relative importance decreased as stress increased. Dispersal limitation and 'drift' related to random birth and death had negative correlations with stresses, whereas the selection processes leading to dissimilar communities increased with stresses, primarily related to pH, cobalt and molybdenum. Assembly mechanisms also varied greatly among different phylogenetic groups. Our findings highlight the importance of microbial dispersal limitation and environmental heterogeneity in ecosystem restoration and management.
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Affiliation(s)
- Daliang Ning
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- School of Biological Sciences, University of Oklahoma, Norman, OK, USA
| | - Yajiao Wang
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- School of Biological Sciences, University of Oklahoma, Norman, OK, USA
| | - Yupeng Fan
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- School of Biological Sciences, University of Oklahoma, Norman, OK, USA
| | - Jianjun Wang
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Joy D Van Nostrand
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
| | - Liyou Wu
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- School of Biological Sciences, University of Oklahoma, Norman, OK, USA
| | - Ping Zhang
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Alkek Center for Metagenomics and Microbiome Research, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Daniel J Curtis
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
| | - Renmao Tian
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Institute for Food Safety and Health, Illinois Institute of Technology, Bedford Park, IL, USA
| | - Lauren Lui
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Terry C Hazen
- Department of Earth and Planetary Sciences, Bredesen Center, Department of Civil and Environmental Sciences, Center for Environmental Biotechnology, and Institute for a Secure and Sustainable Environment, University of Tennessee, Knoxville, TN, USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Department of Bioengineering, University of California, Berkeley, CA, USA
| | - Eric J Alm
- Department of Biological Engineering, Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Matthew W Fields
- Center for Biofilm Engineering and Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Farris Poole
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Romy Chakraborty
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - David A Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - Paul D Adams
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Bioengineering, University of California, Berkeley, CA, USA
| | - Adam P Arkin
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Bioengineering, University of California, Berkeley, CA, USA
| | - Zhili He
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China
| | - Jizhong Zhou
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA.
- School of Biological Sciences, University of Oklahoma, Norman, OK, USA.
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- School of Civil Engineering and Environmental Sciences, University of Oklahoma, Norman, OK, USA.
- School of Computer Science, University of Oklahoma, Norman, OK, USA.
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3
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Molinas M, Meibom KL, Faizova R, Mazzanti M, Bernier-Latmani R. Mechanism of Reduction of Aqueous U(V)-dpaea and Solid-Phase U(VI)-dpaea Complexes: The Role of Multiheme c-Type Cytochromes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:7537-7546. [PMID: 37133831 DOI: 10.1021/acs.est.3c00666] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The biological reduction of soluble U(VI) complexes to form immobile U(IV) species has been proposed to remediate contaminated sites. It is well established that multiheme c-type cytochromes (MHCs) are key mediators of electron transfer to aqueous phase U(VI) complexes for bacteria such as Shewanella oneidensis MR-1. Recent studies have confirmed that the reduction proceeds via a first electron transfer forming pentavalent U(V) species that readily disproportionate. However, in the presence of the stabilizing aminocarboxylate ligand, dpaea2- (dpaeaH2═bis(pyridyl-6-methyl-2-carboxylate)-ethylamine), biologically produced U(V) persisted in aqueous solution at pH 7. We aim to pinpoint the role of MHC in the reduction of U(V)-dpaea and to establish the mechanism of solid-phase U(VI)-dpaea reduction. To that end, we investigated U-dpaea reduction by two deletion mutants of S. oneidensis MR-1-one lacking outer membrane MHCs and the other lacking all outer membrane MHCs and a transmembrane MHC-and by the purified outer membrane MHC, MtrC. Our results suggest that solid-phase U(VI)-dpaea is reduced primarily by outer membrane MHCs. Additionally, MtrC can directly transfer electrons to U(V)-dpaea to form U(IV) species but is not strictly necessary, underscoring the primary involvement of outer membrane MHCs in the reduction of this pentavalent U species but not excluding that of periplasmic MHCs.
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Affiliation(s)
- Margaux Molinas
- Environmental Microbiology Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Karin Lederballe Meibom
- Environmental Microbiology Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Radmila Faizova
- Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Marinella Mazzanti
- Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Rizlan Bernier-Latmani
- Environmental Microbiology Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
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4
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Stagg O, Morris K, Townsend LT, Kvashnina KO, Baker ML, Dempsey RL, Abrahamsen-Mills L, Shaw S. Sulfidation and Reoxidation of U(VI)-Incorporated Goethite: Implications for U Retention during Sub-Surface Redox Cycling. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:17643-17652. [PMID: 36449568 PMCID: PMC9775214 DOI: 10.1021/acs.est.2c05314] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 11/06/2022] [Accepted: 11/08/2022] [Indexed: 06/17/2023]
Abstract
Over 60 years of nuclear activity have resulted in a global legacy of contaminated land and radioactive waste. Uranium (U) is a significant component of this legacy and is present in radioactive wastes and at many contaminated sites. U-incorporated iron (oxyhydr)oxides may provide a long-term barrier to U migration in the environment. However, reductive dissolution of iron (oxyhydr)oxides can occur on reaction with aqueous sulfide (sulfidation), a common environmental species, due to the microbial reduction of sulfate. In this work, U(VI)-goethite was initially reacted with aqueous sulfide, followed by a reoxidation reaction, to further understand the long-term fate of U species under fluctuating environmental conditions. Over the first day of sulfidation, a transient release of aqueous U was observed, likely due to intermediate uranyl(VI)-persulfide species. Despite this, overall U was retained in the solid phase, with the formation of nanocrystalline U(IV)O2 in the sulfidized system along with a persistent U(V) component. On reoxidation, U was associated with an iron (oxyhydr)oxide phase either as an adsorbed uranyl (approximately 65%) or an incorporated U (35%) species. These findings support the overarching concept of iron (oxyhydr)oxides acting as a barrier to U migration in the environment, even under fluctuating redox conditions.
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Affiliation(s)
- Olwen Stagg
- Research
Centre for Radwaste Disposal and Williamson Research Centre for Molecular
Environmental Science, Department of Earth and Environmental Sciences, The University of Manchester, ManchesterM13 9PL, U.K.
| | - Katherine Morris
- Research
Centre for Radwaste Disposal and Williamson Research Centre for Molecular
Environmental Science, Department of Earth and Environmental Sciences, The University of Manchester, ManchesterM13 9PL, U.K.
| | - Luke Thomas Townsend
- Research
Centre for Radwaste Disposal and Williamson Research Centre for Molecular
Environmental Science, Department of Earth and Environmental Sciences, The University of Manchester, ManchesterM13 9PL, U.K.
| | - Kristina O. Kvashnina
- The
Rossendorf Beamline at ESRF—The European Synchrotron, CS40220, Grenoble Cedex 938043France
- Institute
of Resource Ecology, Helmholtz Zentrum Dresden
Rossendorf (HZDR), Dresden01314, Germany
| | - Michael L. Baker
- Department
of Chemistry, The University of Manchester, ManchesterM13 9PL, U.K.
- The
University of Manchester at Harwell, The University of Manchester, Diamond Light Source, Harwell Campus, DidcotOX11 0DE, U.K.
| | - Ryan L. Dempsey
- Department
of Chemistry, The University of Manchester, ManchesterM13 9PL, U.K.
| | | | - Samuel Shaw
- Research
Centre for Radwaste Disposal and Williamson Research Centre for Molecular
Environmental Science, Department of Earth and Environmental Sciences, The University of Manchester, ManchesterM13 9PL, U.K.
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Zeng Q, Zhu T, Wen Y, Li F, Cheng Y, Chen S, Lan T, Yang Y, Liao J, Sun Q, Liu N. The dynamic behavior and mechanism of uranium (VI) biomineralization in Enterobacter sp. X57. CHEMOSPHERE 2022; 298:134196. [PMID: 35276103 DOI: 10.1016/j.chemosphere.2022.134196] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 02/22/2022] [Accepted: 03/01/2022] [Indexed: 06/14/2023]
Abstract
The important role of microbes in the biomineralization and migration behavior of uranium in the field of environmental chemistry has been well emphasized in previous work. However, limited work on mineralization processes of indigenous microorganism has prevented us from a deeper understanding of the process and mechanisms of uranium biomineralization. In this work, the dynamic process and mechanism of uranium biomineralization in Enterobacter sp. X57, a novel uranium-tolerant microorganism separated from uranium contaminated soil, were systematically investigated. Enterobacter sp. X57 can induce intracellular mineralization of U (VI) to Uramphite (NH4UO2PO4·3H2O) under neutral conditions by alkaline phosphatase. In this biomineralization process, soluble U (VI) first bonded with the amino and phosphate groups on the plasma membrane, providing initial nucleation site for the formation of U (VI) biominerals. Then the impairment of cell barrier function and the enhancement of alkaline phosphatase metabolism occurred with the accumulation of uranium in cells, creating a possible pathway for soluble U (VI) to diffuse into the cell and be further mineralized into U (VI)-phosphate minerals. All the results revealed that the intracellular biomineralization of uranium by Enterobacter sp. X57 was a combined result of biosorption, intracellular accumulation and phosphatase metabolism. These findings may contribute to a better understanding of uranium biomineralization behavior and mechanism of microorganisms, as well as possible in-situ bioremediation strategies for uranium by indigenous microorganisms.
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Affiliation(s)
- Qian Zeng
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China
| | - Ting Zhu
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China; Key Laboratory of Biological Resource and Ecological Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, PR China
| | - Yufeng Wen
- Department of Life Sciences, Jilin University, Street Qianjin 2699, Changchun, 130012, PR China
| | - Feize Li
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China
| | - Yanxia Cheng
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China
| | - Shunzhang Chen
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China
| | - Tu Lan
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China
| | - Yuanyou Yang
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China
| | - Jiali Liao
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China.
| | - Qun Sun
- Key Laboratory of Biological Resource and Ecological Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, PR China
| | - Ning Liu
- Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, PR China
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Akash S, Sivaprakash B, Raja VCV, Rajamohan N, Muthusamy G. Remediation techniques for uranium removal from polluted environment - Review on methods, mechanism and toxicology. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 302:119068. [PMID: 35240271 DOI: 10.1016/j.envpol.2022.119068] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/20/2022] [Accepted: 02/25/2022] [Indexed: 05/27/2023]
Abstract
Uranium, a radionuclide, is a predominant element utilized for speciality requirements in industrial applications, as fuels and catalyst. The radioactive properties and chemical toxicity of uranium causes a major threat to the ecosystem. The hazards associated with Uranium pollution includes the cancer in bones, liver, and lungs. The toxicological properties of Uranium are discussed in detail. Although there are many methods to eliminate those hazards, this research work is aimed to describe the application of bioremediation methods. Bioremediation methods involve elimination of the hazards of uranium, by transforming into low oxidation form using natural microbes and plants. This study deeply elucidates the methods as bioleaching, biosorption, bioreduction and phytoremediation. Bioleaching process involves bio-oxidation of tetravalent uranium when it gets in contact with acidophilic metal bacterial complex to obtain leach liquor. In biosorption, chitin/chitosan derived sorbents act as chelators and binds with uranium by electrostatic attraction. Bio reduction employs a bacterial transformation into enzymes which immobilize and reduce uranium. Phytoremediation includes phytoextraction and phytotranslocation of uranium through xylems from soil to roots and shoots of plants. The highest uranium removal and uptake reported using the different methods are listed as follows: bioleaching (100% uranium recovery), biosorption (167 g kg-1 uranium uptake), bioreduction (98.9% uranium recovery), and phytoremediation (49,639 mg kg-1 uranium uptake). Among all the techniques mentioned above, bioleaching has been proved to be the most efficient for uranium remediation.
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Affiliation(s)
- S Akash
- Department of Chemical Engineering, Annamalai University, Annamalai Nagar PC, 608002, India
| | - Baskaran Sivaprakash
- Department of Chemical Engineering, Annamalai University, Annamalai Nagar PC, 608002, India
| | - V C Vadivel Raja
- Department of Chemical Engineering, Annamalai University, Annamalai Nagar PC, 608002, India
| | - Natarajan Rajamohan
- Chemical Engineering Section, Faculty of Engineering, Sohar University, Sohar, PC-311, Oman.
| | - Govarthanan Muthusamy
- Department of Environmental Engineering, Kyungpook National University, Daegu, South Korea
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Paradis CJ, Miller JI, Moon J, Spencer SJ, Lui LM, Van Nostrand JD, Ning D, Steen AD, McKay LD, Arkin AP, Zhou J, Alm EJ, Hazen TC. Sustained Ability of a Natural Microbial Community to Remove Nitrate from Groundwater. GROUND WATER 2022; 60:99-111. [PMID: 34490626 PMCID: PMC9290691 DOI: 10.1111/gwat.13132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/24/2021] [Accepted: 08/30/2021] [Indexed: 05/23/2023]
Abstract
Microbial-mediated nitrate removal from groundwater is widely recognized as the predominant mechanism for nitrate attenuation in contaminated aquifers and is largely dependent on the presence of a carbon-bearing electron donor. The repeated exposure of a natural microbial community to an electron donor can result in the sustained ability of the community to remove nitrate; this phenomenon has been clearly demonstrated at the laboratory scale. However, in situ demonstrations of this ability are lacking. For this study, ethanol (electron donor) was repeatedly injected into a groundwater well (treatment) for six consecutive weeks to establish the sustained ability of a microbial community to remove nitrate. A second well (control) located upgradient was not injected with ethanol during this time. The treatment well demonstrated strong evidence of sustained ability as evident by ethanol, nitrate, and subsequent sulfate removal up to 21, 64, and 68%, respectively, as compared to the conservative tracer (bromide) upon consecutive exposures. Both wells were then monitored for six additional weeks under natural (no injection) conditions. During the final week, ethanol was injected into both treatment and control wells. The treatment well demonstrated sustained ability as evident by ethanol and nitrate removal up to 20 and 21%, respectively, as compared to bromide, whereas the control did not show strong evidence of nitrate removal (5% removal). Surprisingly, the treatment well did not indicate a sustained and selective enrichment of a microbial community. These results suggested that the predominant mechanism(s) of sustained ability likely exist at the enzymatic- and/or genetic-levels. The results of this study demonstrated the in situ ability of a microbial community to remove nitrate can be sustained in the prolonged absence of an electron donor.
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Affiliation(s)
- Charles J. Paradis
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
| | - John I. Miller
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
- Bredesen CenterUniversity of TennesseeKnoxvilleTN
| | - Ji‐Won Moon
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
| | - Sarah J. Spencer
- Biological Engineering DepartmentMassachusetts Institute of TechnologyCambridgeMA
| | - Lauren M. Lui
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA
| | - Joy D. Van Nostrand
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Daliang Ning
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Andrew D. Steen
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Department of MicrobiologyUniversity of TennesseeKnoxvilleTN
| | - Larry D. McKay
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
| | - Adam P. Arkin
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA
- Department of BioengineeringUniversity of CaliforniaBerkeleyCA
| | - Jizhong Zhou
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Eric J. Alm
- Biological Engineering DepartmentMassachusetts Institute of TechnologyCambridgeMA
| | - Terry C. Hazen
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
- Bredesen CenterUniversity of TennesseeKnoxvilleTN
- Department of BioengineeringUniversity of CaliforniaBerkeleyCA
- Department of Civil and Environmental SciencesUniversity of TennesseeKnoxvilleTN
- Center for Environmental BiotechnologyUniversity of TennesseeKnoxvilleTN
- Institute for a Secure and Sustainable EnvironmentUniversity of TennesseeKnoxvilleTN
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8
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You W, Peng W, Tian Z, Zheng M. Uranium bioremediation with U(VI)-reducing bacteria. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 798:149107. [PMID: 34325147 DOI: 10.1016/j.scitotenv.2021.149107] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/13/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Uranium (U) pollution is an environmental hazard caused by the development of the nuclear industry. Microbial reduction of hexavalent uranium (U(VI)) to tetravalent uranium (U(IV)) reduces U solubility and mobility and has been proposed as an effective method to remediate uranium contamination. In this review, U(VI) remediation with respect to U(VI)-reducing bacteria, mechanisms, influencing factors, products, and reoxidation are systematically summarized. Reportedly, some metal- and sulfate-reducing bacteria possess excellent U(VI) reduction capability through mechanisms involving c-type cytochromes, extracellular pili, electron shuttle, or thioredoxin reduction. In situ remediation has been demonstrated as an ideal strategy for large-scale degradation of uranium contaminants than ex situ. However, U(VI) reduction efficiency can be affected by various factors, including pH, temperature, bicarbonate, electron donors, and coexisting metal ions. Furthermore, it is noteworthy that the reduction products could be reoxidized when exposed to oxygen and nitrate, inevitably compromising the remediation effects, especially for non-crystalline U(IV) with weak stability.
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Affiliation(s)
- Wenbo You
- Key Laboratory of Regional Energy Systems Optimization, Ministry of Education, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China
| | - Wanting Peng
- Key Laboratory of Regional Energy Systems Optimization, Ministry of Education, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China
| | - Zhichao Tian
- Key Laboratory of Regional Energy Systems Optimization, Ministry of Education, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China
| | - Maosheng Zheng
- Key Laboratory of Regional Energy Systems Optimization, Ministry of Education, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
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9
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Deciphering Microbial Metal Toxicity Responses via Random Bar Code Transposon Site Sequencing and Activity-Based Metabolomics. Appl Environ Microbiol 2021; 87:e0103721. [PMID: 34432491 DOI: 10.1128/aem.01037-21] [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] [Indexed: 11/20/2022] Open
Abstract
To uncover metal toxicity targets and defense mechanisms of the facultative anaerobe Pantoea sp. strain MT58 (MT58), we used a multiomic strategy combining two global techniques, random bar code transposon site sequencing (RB-TnSeq) and activity-based metabolomics. MT58 is a metal-tolerant Oak Ridge Reservation (ORR) environmental isolate that was enriched in the presence of metals at concentrations measured in contaminated groundwater at an ORR nuclear waste site. The effects of three chemically different metals found at elevated concentrations in the ORR contaminated environment were investigated: the cation Al3+, the oxyanion CrO42-, and the oxycation UO22+. Both global techniques were applied using all three metals under both aerobic and anaerobic conditions to elucidate metal interactions mediated through the activity of metabolites and key genes/proteins. These revealed that Al3+ binds intracellular arginine, CrO42- enters the cell through sulfate transporters and oxidizes intracellular reduced thiols, and membrane-bound lipopolysaccharides protect the cell from UO22+ toxicity. In addition, the Tol outer membrane system contributed to the protection of cellular integrity from the toxic effects of all three metals. Likewise, we found evidence of regulation of lipid content in membranes under metal stress. Individually, RB-TnSeq and metabolomics are powerful tools to explore the impact various stresses have on biological systems. Here, we show that together they can be used synergistically to identify the molecular actors and mechanisms of these pertubations to an organism, furthering our understanding of how living systems interact with their environment. IMPORTANCE Studying microbial interactions with their environment can lead to a deeper understanding of biological molecular mechanisms. In this study, two global techniques, RB-TnSeq and activity metabolomics, were successfully used to probe the interactions between a metal-resistant microorganism, Pantoea sp. strain MT58, and metals contaminating a site where the organism can be located. A number of novel metal-microbe interactions were uncovered, including Al3+ toxicity targeting arginine synthesis, which could lead to a deeper understanding of the impact Al3+ contamination has on microbial communities as well as its impact on higher-level organisms, including plants for whom Al3+ contamination is an issue. Using multiomic approaches like the one described here is a way to further our understanding of microbial interactions and their impacts on the environment overall.
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10
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Effect of natural pyrite oxidation on the U(VI) adsorption under the acidic and neutral conditions. J Radioanal Nucl Chem 2021. [DOI: 10.1007/s10967-021-07857-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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11
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Biogeochemical Modelling of Uranium Immobilization and Aquifer Remediation Strategies Near NCCP Sludge Storage Facilities. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11062875] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Nitrate is a substance which influences the prevailing redox conditions in groundwater, and in turn the behaviour of U. The study of groundwater in an area with low-level radioactive sludge storage facilities has shown their contamination with sulphate and nitrate anions, uranium, and some associated metals. The uranyl ion content in the most contaminated NO3–Cl–SO4–Na borehole is 2000 times higher (1.58 mg/L) than that in the background water. At the same time, assessment of the main physiological groups of microorganisms showed a maximum number of denitrifying and sulphate-reducing bacteria (e.g., Sulfurimonas) in the water from the same borehole. Biogenic factors of radionuclide immobilization on sandy rocks of upper aquifers have been experimentally investigated. Different reduction rates of NO3−, SO42−, Fe(III) and U(VI) with stimulated microbial activity were dependent on the pollution degree. Moreover, 16S rRNA gene analysis of the microbial community after whey addition revealed a significant decrease in microbial diversity and the activation of nonspecific nitrate-reducing bacteria (genera Rhodococcus and Rhodobacter). The second influential factor can be identified as the formation of microbial biofilms on the sandy loam samples, which has a positive effect on U sorption (an increase in Kd value is up to 35%). As PHREEQC physicochemical modelling numerically confirmed, the third most influential factor that drives U mobility is the biogenic-mediated formation of a sulphide redox buffer. This study brings important information, which helps to assess the long-term stability of U in the environment of radioactive sludge storage facilities.
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12
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Sánchez-Castro I, Martínez-Rodríguez P, Jroundi F, Solari PL, Descostes M, Merroun ML. High-efficient microbial immobilization of solved U(VI) by the Stenotrophomonas strain Br8. WATER RESEARCH 2020; 183:116110. [PMID: 32659540 DOI: 10.1016/j.watres.2020.116110] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/23/2020] [Accepted: 06/24/2020] [Indexed: 06/11/2023]
Abstract
The environmental impact of uranium released during nuclear power production and related mining activity is an issue of great concern. Innovative environmental-friendly water remediation strategies, like those based on U biomineralization through phosphatase activity, are desirable. Here, we report the great U biomineralization potential of Stenotrophomonas sp. Br8 CECT 9810 over a wide range of physicochemical and biological conditions. Br8 cells exhibited high phosphatase activity which mediated the release of orthophosphate in the presence of glycerol-2-phosphate around pH 6.3. Mobile uranyl ions were bioprecipitated as needle-like fibrils at the cell surface and in the extracellular space, as observed by Scanning Transmission Electron Microscopy (STEM). Extended X-Ray Absorption Fine Structure (EXAFS) and X-Ray Diffraction (XRD) analyses showed the local structure of biogenic U precipitates to be similar to that of meta-autunite. In addition to the active U phosphate biomineralization process, the cells interact with this radionuclide through passive biosorption, removing up to 373 mg of U per g of bacterial dry biomass. The high U biomineralization capacity of the studied strain was also observed under different conditions of pH, temperature, etc. Results presented in this work will help to design efficient U bioremediation strategies for real polluted waters.
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Affiliation(s)
- Iván Sánchez-Castro
- Department of Microbiology, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain.
| | - Pablo Martínez-Rodríguez
- Department of Microbiology, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Fadwa Jroundi
- Department of Microbiology, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Pier Lorenzo Solari
- Synchrotron SOLEIL, MARS beamline, L'Orme des Merisiers, Saint-Aubin BP 48, 91192, Gif-sur-Yvette Cedex, France
| | | | - Mohamed Larbi Merroun
- Department of Microbiology, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
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13
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Li PS, Wu WM, Phillips DH, Watson DB, Kelly S, Li B, Mehlhorn T, Lowe K, Earles J, Tao HC, Zhang T, Criddle CS. Uranium sequestration in sediment at an iron-rich contaminated site at Oak Ridge, Tennessee via. bioreduction followed by reoxidation. J Environ Sci (China) 2019; 85:156-167. [PMID: 31471022 DOI: 10.1016/j.jes.2019.05.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 06/10/2023]
Abstract
This study evaluated uranium sequestration performance in iron-rich (30 g/kg) sediment via bioreduction followed by reoxidation. Field tests (1383 days) at Oak Ridge, Tennessee demonstrated that uranium contents in sediments increased after bioreduced sediments were re-exposed to nitrate and oxygen in contaminated groundwater. Bioreduction of contaminated sediments (1200 mg/kg U) with ethanol in microcosm reduced aqueous U from 0.37 to 0.023 mg/L. Aliquots of the bioreduced sediment were reoxidized with O2, H2O2, and NaNO3, respectively, over 285 days, resulting in aqueous U of 0.024, 1.58 and 14.4 mg/L at pH 6.30, 6.63 and 7.62, respectively. The source- and the three reoxidized sediments showed different desorption and adsorption behaviors of U, but all fit a Freundlich model. The adsorption capacities increased sharply at pH 4.5 to 5.5, plateaued at pH 5.5 to 7.0, then decreased sharply as pH increased from 7.0 to 8.0. The O2-reoxidized sediment retained a lower desorption efficiency at pH over 6.0. The NO3--reoxidized sediment exhibited higher adsorption capacity at pH 5.5 to 6.0. The pH-dependent adsorption onto Fe(III) oxides and formation of U coated particles and precipitates resulted in U sequestration, and bioreduction followed by reoxidation can enhance the U sequestration in sediment.
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Affiliation(s)
- Peng-Song Li
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA; Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Institute of New Energy Technology, Tsinghua University, Beijing 100084, China
| | - Wei-Min Wu
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA.
| | - Debra H Phillips
- School of Natural and Built Environment, Queen's University Belfast, Belfast BT9 5AG, Northern Ireland, UK
| | - David B Watson
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA
| | | | - Bing Li
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA; Department of Civil Engineering, The University of Hong Kong, Hong Kong, China
| | - Tonia Mehlhorn
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA
| | - Kenneth Lowe
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA
| | - Jennifer Earles
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA
| | - Hu-Chun Tao
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Tong Zhang
- Department of Civil Engineering, The University of Hong Kong, Hong Kong, China
| | - Craig S Criddle
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA.
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14
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Bioelectrochemical Systems for Groundwater Remediation: The Development Trend and Research Front Revealed by Bibliometric Analysis. WATER 2019. [DOI: 10.3390/w11081532] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
: Due to the deficiency of fresh water resources and the deterioration of groundwater quality worldwide, groundwater remedial technologies are especially crucial for preventing groundwater pollution and protecting the precious groundwater resource. Among the remedial alternatives, bioelectrochemical systems have unique advantages on both economic and technological aspects. However, it is rare to see a deep study focused on the information mining and visualization of the publications in this field, and research that can reveal and visualize the development trajectory and trends is scarce. Therefore, this study summarizes the published information in this field from the Web of Science Core Collection of the last two decades (1999–2018) and uses Citespace to quantitatively visualize the relationship of authors, published countries, organizations, funding sources, and journals and detect the research front by analyzing keywords and burst terms. The results indicate that the studies focused on bioelectrochemical systems for groundwater remediation have had a significant increase during the last two decades, especially in China, Germany and Italy. The national research institutes and universities of the USA and the countries mentioned above dominate the research. Environmental Science & Technology, Applied and Environmental Microbiology, and Water Research are the most published journals in this field. The network maps of the keywords and burst terms suggest that reductive microbial diversity, electron transfer, microbial fuel cell, etc., are the research hotspots in recent years, and studies focused on microbial enrichment culture, energy supply/recovery, combined pollution remediation, etc., should be enhanced in future.
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15
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Reimus PW, Dangelmayr MA, Clay JT, Chamberlain KR. Uranium Natural Attenuation Downgradient of an in Situ Recovery Mine Inferred from a Cross-Hole Field Test. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:7483-7493. [PMID: 31132251 DOI: 10.1021/acs.est.9b01572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A field test was conducted at a uranium in situ recovery (solution mining) site to evaluate postmining uranium natural attenuation downgradient of an ore zone. Approximately 1 million liters of water from a previously mined ore zone was injected into an unmined ore zone that served as a proxy for a downgradient aquifer, while a well located approximately 23 m away was pumped. After 1 year of pumping, only about 39% of the injected U(VI) was recovered, whereas essentially 100% of coinjected chloride was recovered. A geochemical/transport model was used to simultaneously match the chloride and uranium concentrations at the pumping well while also qualitatively matching aqueous 238U/235U ratios, which reflect uranium removal from solution by reduction. It was concluded that ∼50% of the injected U(VI) was reduced to U(IV), although the reduction capacity in the flow pathways between the injection and production wells was estimated to be nearly exhausted by the end of the test. Estimating the reduction capacity of the downgradient aquifer can inform restoration strategy and offer a useful metric for regulatory decisions concerning the adequacy of restoration. U(VI) reduction should be effectively irreversible in these anoxic environments, which differ greatly from shallow oxic environments where U(IV) is readily reoxidized.
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Affiliation(s)
- Paul W Reimus
- Los Alamos National Laboratory , P.O. Box 1663, Los Alamos , New Mexico 87545 , United States
| | - Martin A Dangelmayr
- Los Alamos National Laboratory , P.O. Box 1663, Los Alamos , New Mexico 87545 , United States
| | - James T Clay
- Cameco Resources, Inc. , 762 Ross Road , Douglas , Wyoming 82633 , United States
| | - Kevin R Chamberlain
- University of Wyoming , Department of Geology and Geophysics , 1000 East University Avenue , Dept. 3006, Laramie , Wyoming 82071 , United States
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16
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Lakaniemi AM, Douglas GB, Kaksonen AH. Engineering and kinetic aspects of bacterial uranium reduction for the remediation of uranium contaminated environments. JOURNAL OF HAZARDOUS MATERIALS 2019; 371:198-212. [PMID: 30851673 DOI: 10.1016/j.jhazmat.2019.02.074] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 01/29/2019] [Accepted: 02/20/2019] [Indexed: 06/09/2023]
Abstract
Biological reduction of soluble uranium from U(VI) to insoluble U(IV) coupled to the oxidation of an electron donor (hydrogen or organic compounds) is a potentially cost-efficient way to reduce the U concentrations in contaminated waters to below regulatory limits. A variety of microorganisms originating from both U contaminated and non-contaminated environments have demonstrated U(VI) reduction capacity under anaerobic conditions. Bioreduction of U(VI) is considered especially promising for in situ remediation, where the activity of indigenous microorganisms is stimulated by supplying a suitable electron donor to the subsurface to contain U contamination to a specific location in a sparingly soluble form. Less studied microbial biofilm-based bioreactors and bioelectrochemical systems have also shown potential for efficient U(VI) reduction to remove U from contaminated water streams. This review compares the advantages and challenges of U(VI)-reducing in situ remediation processes, bioreactors and bioelectrochemical systems. In addition, the current knowledge of U(VI) bioreduction mechanisms and factors affecting U(VI) reduction kinetics (e.g. pH, temperature, and the chemical composition of the contaminated water) are discussed, as both of these aspects are important in designing efficient remediation processes.
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Affiliation(s)
- Aino-Maija Lakaniemi
- Tampere University, Faculty of Engineering and Natural Sciences, P.O. Box 541, FI- 33104, Tampere University, Finland; CSIRO Land and Water, 147 Underwood Avenue, Floreat, Western Australia, 6014, Australia.
| | - Grant B Douglas
- CSIRO Land and Water, 147 Underwood Avenue, Floreat, Western Australia, 6014, Australia
| | - Anna H Kaksonen
- CSIRO Land and Water, 147 Underwood Avenue, Floreat, Western Australia, 6014, Australia
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17
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Holmes DE, Dang Y, Smith JA. Nitrogen cycling during wastewater treatment. ADVANCES IN APPLIED MICROBIOLOGY 2019; 106:113-192. [PMID: 30798802 DOI: 10.1016/bs.aambs.2018.10.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many wastewater treatment plants in the world do not remove reactive nitrogen from wastewater prior to release into the environment. Excess reactive nitrogen not only has a negative impact on human health, it also contributes to air and water pollution, and can cause complex ecosystems to collapse. In order to avoid the deleterious effects of excess reactive nitrogen in the environment, tertiary wastewater treatment practices that ensure the removal of reactive nitrogen species need to be implemented. Many wastewater treatment facilities rely on chemicals for tertiary treatment, however, biological nitrogen removal practices are much more environmentally friendly and cost effective. Therefore, interest in biological treatment is increasing. Biological approaches take advantage of specific groups of microorganisms involved in nitrogen cycling to remove reactive nitrogen from reactor systems by converting ammonia to nitrogen gas. Organisms known to be involved in this process include autotrophic ammonia-oxidizing bacteria, heterotrophic ammonia-oxidizing bacteria, ammonia-oxidizing archaea, anaerobic ammonia oxidizing bacteria (anammox), nitrite-oxidizing bacteria, complete ammonia oxidizers, and dissimilatory nitrate reducing microorganisms. For example, in nitrifying-denitrifying reactors, ammonia- and nitrite-oxidizing bacteria convert ammonia to nitrate and then denitrifying microorganisms reduce nitrate to nonreactive dinitrogen gas. Other nitrogen removal systems (anammox reactors) take advantage of anammox bacteria to convert ammonia to nitrogen gas using NO as an oxidant. A number of promising new biological treatment technologies are emerging and it is hoped that as the cost of these practices goes down more wastewater treatment plants will start to include a tertiary treatment step.
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18
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Pan D, Williams KH, Robbins MJ, Weber KA. Uranium Retention in a Bioreduced Region of an Alluvial Aquifer Induced by the Influx of Dissolved Oxygen. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:8133-8145. [PMID: 29996052 DOI: 10.1021/acs.est.8b00903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Reduced zones in the subsurface represent biogeochemically active hotspots enriched in buried organic matter and reduced metals. Within a shallow alluvial aquifer located near Rifle, CO, reduced zones control the fate and transport of uranium (U). Though an influx of dissolved oxygen (DO) would be expected to mobilize U, we report U immobilization. Groundwater U concentrations decreased following delivery of DO (21.6 mg O2/well/h). After 23 days of DO delivery, injection of oxygenated groundwater was paused and resulted in the rebound of groundwater U concentrations to preinjection levels. When DO delivery resumed (day 51), groundwater U concentrations again decreased. The injection was halted on day 82 again and resulted in a rebound of groundwater U concentrations. DO delivery rate was increased to 54 mg O2/well/h (day 95) whereby groundwater U concentrations increased. Planktonic cell abundance remained stable throughout the experiment, but virus-to-microbial cell ratio increased 1.8-3.4-fold with initial DO delivery, indicative of microbial activity in response to DO injection. Together, these results indicate that the redox-buffering capacity of reduced sediments can prevent U mobilization, but could be overcome as delivery rate or oxidant concentration increases, mobilizing U.
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Affiliation(s)
- Donald Pan
- School of Biological Sciences , University of Nebraska-Lincoln , Lincoln , Nebraska 68588 , United States
| | - Kenneth H Williams
- Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Mark J Robbins
- Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Karrie A Weber
- School of Biological Sciences , University of Nebraska-Lincoln , Lincoln , Nebraska 68588 , United States
- Department of Earth and Atmospheric Sciences , University of Nebraska-Lincoln , Lincoln , Nebraska 68588 , United States
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19
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Song W, Wang X, Chen Z, Sheng G, Hayat T, Wang X, Sun Y. Enhanced immobilization of U(VI) on Mucor circinelloides in presence of As(V): Batch and XAFS investigation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 237:228-236. [PMID: 29486456 DOI: 10.1016/j.envpol.2018.02.060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 01/16/2018] [Accepted: 02/19/2018] [Indexed: 06/08/2023]
Abstract
The combined pollution of radionuclides and heavy metals has been given rise to widespread concern during uranium mining. The influence of As(V) on U(VI) immobilization by Mucor circinelloides (M. circinelloides) was investigated using batch experiments. The activity of antioxidative enzymes and concentrations of thiol compounds and organic acid in M. circinelloides increased to respond to different U(VI) and As(V) stress. The morphological structure of M. circinelloides changed obviously under U(VI) and As(V) stress by SEM and TEM analysis. The results of XANES and EXAFS analysis showed that U(VI) was mainly reduced to nano-uraninite (nano-UO2, 30.1%) in U400, while only 9.7% of nano-UO2 was observed in the presence of As(V) in U400-As400 due to the formation of uranyl arsenate precipitate (Trögerite, 48.6%). These observations will provide the fundamental data for fungal remediation of uranium and heavy metals in uranium-contaminated soils.
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Affiliation(s)
- Wencheng Song
- Anhui Province Key Laboratory of Medical Physics Technology and Center of Medical Physics and Technology, Hefei Institutes of Physical Sciences and Hefei Cancer Hospital, Chinese Academy of Sciences, Hefei 230031, PR China; College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, PR China
| | - Xiangxue Wang
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, PR China
| | - Zhongshan Chen
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, PR China
| | - Guodong Sheng
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, PR China; College of Chemistry and Chemical Engineering, Shaoxing University, Zhejiang 312000, PR China
| | - Tasawar Hayat
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions and School for Radiological and Interdisciplinary Sciences, Soochow University, 215123, Suzhou, PR China
| | - Xiangke Wang
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, PR China; Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions and School for Radiological and Interdisciplinary Sciences, Soochow University, 215123, Suzhou, PR China; NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Yubing Sun
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, PR China.
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20
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Shen Y, Zheng X, Wang X, Wang T. The biomineralization process of uranium(VI) by Saccharomyces cerevisiae - transformation from amorphous U(VI) to crystalline chernikovite. Appl Microbiol Biotechnol 2018; 102:4217-4229. [PMID: 29564524 DOI: 10.1007/s00253-018-8918-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 03/05/2018] [Accepted: 03/06/2018] [Indexed: 11/30/2022]
Abstract
Microorganisms play a significant role in uranium(VI) biogeochemistry and influence U(VI) transformation through biomineralization. In the present work, the process of uranium mineralization was investigated by Saccharomyces cerevisiae. The toxicity experiments showed that the viability of cell was not significantly affected by 100 mg L-1 U(VI) under 4 days of exposure time. The batch experiments showed that the phosphate concentration and pH value increased over time during U(VI) adsorption. Meanwhile, thermodynamic calculations demonstrated that the adsorption system was supersaturated with respect to UO2HPO4. The X-ray powder diffraction spectroscopy (XRD), field emission scanning electron microscopy (FE-SEM) equipped with energy dispersive spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) analyses indicated that the U(VI) was first attached onto the cell surface and reacted with hydroxyl, carboxyl, and phosphate groups through electrostatic interactions and complexation. As the immobilization of U(VI) transformed it from the ionic to the amorphous state, lamellar uranium precipitate was formed on the cell surface. With the prolongation of time, the amorphous uranium compound disappeared, and there were some crystalline substances observed extracellularly, which were well-characterized as tetragonal-chernikovite. Furthermore, the size of chernikovite was regulated at nano-level by cells, and the perfect crystal was formed finally. These findings provided an understanding of the non-reductive transformation process of U(VI) from the amorphous to crystalline state within microbe systems, which would be beneficial for the U(VI) treatment and reuse of nuclides and heavy metals.
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Affiliation(s)
- Yanghao Shen
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou, 730000, China
| | - Xinyan Zheng
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou, 730000, China
| | - Xiaoyu Wang
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou, 730000, China
| | - Tieshan Wang
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou, 730000, China.
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21
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Masters-Waage NK, Morris K, Lloyd JR, Shaw S, Mosselmans JFW, Boothman C, Bots P, Rizoulis A, Livens FR, Law GTW. Impacts of Repeated Redox Cycling on Technetium Mobility in the Environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:14301-14310. [PMID: 29144125 DOI: 10.1021/acs.est.7b02426] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Technetium is a problematic contaminant at nuclear sites and little is known about how repeated microbiologically mediated redox cycling impacts its fate in the environment. We explore this question in sediments representative of the Sellafield Ltd. site, UK, over multiple reduction and oxidation cycles spanning ∼1.5 years. We found the amount of Tc remobilised from the sediment into solution significantly decreased after repeated redox cycles. X-ray Absorption Spectroscopy (XAS) confirmed that sediment bound Tc was present as hydrous TcO2-like chains throughout experimentation and that Tc's increased resistance to remobilization (via reoxidation to soluble TcO4-) resulted from both shortening of TcO2 chains during redox cycling and association of Tc(IV) with Fe phases in the sediment. We also observed that Tc(IV) remaining in solution during bioreduction was likely associated with colloidal magnetite nanoparticles. These findings highlight crucial links between Tc and Fe biogeochemical cycles that have significant implications for Tc's long-term environmental mobility, especially under ephemeral redox conditions.
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Affiliation(s)
- Nicholas K Masters-Waage
- Centre for Radiochemistry Research, School of Chemistry, The University of Manchester , M13 9PL, Manchester, United Kingdom
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences, The University of Manchester , M13 9PL, Manchester, United Kingdom
| | - Katherine Morris
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences, The University of Manchester , M13 9PL, Manchester, United Kingdom
| | - Jonathan R Lloyd
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences, The University of Manchester , M13 9PL, Manchester, United Kingdom
| | - Samuel Shaw
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences, The University of Manchester , M13 9PL, Manchester, United Kingdom
| | - J Frederick W Mosselmans
- Diamond Light Source Ltd ., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom
| | - Christopher Boothman
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences, The University of Manchester , M13 9PL, Manchester, United Kingdom
| | - Pieter Bots
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences, The University of Manchester , M13 9PL, Manchester, United Kingdom
| | - Athanasios Rizoulis
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences, The University of Manchester , M13 9PL, Manchester, United Kingdom
| | - Francis R Livens
- Centre for Radiochemistry Research, School of Chemistry, The University of Manchester , M13 9PL, Manchester, United Kingdom
| | - Gareth T W Law
- Centre for Radiochemistry Research, School of Chemistry, The University of Manchester , M13 9PL, Manchester, United Kingdom
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22
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Li D, Egodawatte S, Kaplan DI, Larsen SC, Serkiz SM, Seaman JC, Scheckel KG, Lin J, Pan Y. Sequestration of U(VI) from Acidic, Alkaline, and High Ionic-Strength Aqueous Media by Functionalized Magnetic Mesoporous Silica Nanoparticles: Capacity and Binding Mechanisms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:14330-14341. [PMID: 29151341 PMCID: PMC5894121 DOI: 10.1021/acs.est.7b03778] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Uranium(VI) exhibits little adsorption onto sediment minerals in acidic, alkaline or high ionic-strength aqueous media that often occur in U mining or contaminated sites, which makes U(VI) very mobile and difficult to sequester. In this work, magnetic mesoporous silica nanoparticles (MMSNs) were functionalized with several organic ligands. The functionalized MMSNs were highly effective and had large binding capacity for U sequestration from high salt water (HSW) simulant (54 mg U/g sorbent). The functionalized MMSNs, after U exposure in HSW simulant, pH 3.5 and 9.6 artificial groundwater (AGW), were characterized by a host of spectroscopic methods. Among the key novel findings in this work was that in the HSW simulant or high pH AGW, the dominant U species bound to the functionalized MMSNs were uranyl or uranyl hydroxide, rather than uranyl carbonates as expected. The surface functional groups appear to be out-competing the carbonate ligands associated with the aqueous U species. The uranyl-like species were bound with N ligand as η2 bound motifs or phosphonate ligand as a monodentate, as well as on tetrahedral Si sites as an edge-sharing bidentate. The N and phosphonate ligand-functionalized MMSNs hold promise as effective sorbents for sequestering U from acidic, alkaline or high ionic-strength contaminated aqueous media.
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Affiliation(s)
- Dien Li
- Savannah River National Laboratory, Aiken, SC 29808, USA
- Corresponding Author: Phone: 803 725 7520. Fax: 803 725 7673.
| | - Shani Egodawatte
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA
| | | | - Sarah C. Larsen
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA
| | - Steven M. Serkiz
- Savannah River National Laboratory, Aiken, SC 29808, USA
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA
| | - John C. Seaman
- Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA
| | - Kirk G. Scheckel
- U.S. Environmental Protection Agency, National Risk Management Research Laboratory, Cincinnati, Ohio 45224, USA
| | - Jinru Lin
- Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK S7N 5A5, Canada
| | - Yuanming Pan
- Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK S7N 5A5, Canada
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23
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Decontamination of U(VI) from nZVI/CNF composites investigated by batch, spectroscopic and modeling techniques. J Mol Liq 2017. [DOI: 10.1016/j.molliq.2017.04.084] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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24
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Zhang P, He Z, Van Nostrand JD, Qin Y, Deng Y, Wu L, Tu Q, Wang J, Schadt CW, W Fields M, Hazen TC, Arkin AP, Stahl DA, Zhou J. Dynamic Succession of Groundwater Sulfate-Reducing Communities during Prolonged Reduction of Uranium in a Contaminated Aquifer. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:3609-3620. [PMID: 28300407 DOI: 10.1021/acs.est.6b02980] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
To further understand the diversity and dynamics of SRB in response to substrate amendment, we sequenced genes coding for the dissimilatory sulfite reductase (dsrA) in groundwater samples collected after an emulsified vegetable oil (EVO) amendment, which sustained U(VI)-reducing conditions for one year in a fast-flowing aquifer. EVO amendment significantly altered the composition of groundwater SRB communities. Sequences having no closely related-described species dominated (80%) the indigenous SRB communities in nonamended wells. After EVO amendment, Desulfococcus, Desulfobacterium, and Desulfovibrio, known for long-chain-fatty-acid, short-chain-fatty-acid and H2 oxidation and U(VI) reduction, became dominant accounting for 7 ± 2%, 21 ± 8%, and 55 ± 8% of the SRB communities, respectively. Succession of these SRB at different bioactivity stages based on redox substrates/products (acetate, SO4-2, U(VI), NO3-, Fe(II), and Mn(II)) was observed. Desulfovibrio and Desulfococcus dominated SRB communities at 4-31 days, whereas Desulfobacterium became dominant at 80-140 days. By the end of the experiment (day 269), the abundance of these SRB decreased but the overall diversity of groundwater SRB was still higher than non-EVO controls. Up to 62% of the SRB community changes could be explained by groundwater geochemical variables, including those redox substrates/products. A significant (P < 0.001) correlation was observed between groundwater U(VI) concentrations and Desulfovibrio abundance. Our results showed that the members of SRB and their dynamics were correlated significantly with slow EVO biodegradation, electron donor production and maintenance of U(VI)-reducing conditions in the aquifer.
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Affiliation(s)
- Ping Zhang
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
| | - Zhili He
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
| | - Joy D Van Nostrand
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
| | - Yujia Qin
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
| | - Ye Deng
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
- Research Center for Eco-Environmental Science, Chinese Academy of Sciences , Beijing 100085, China
| | - Liyou Wu
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
| | - Qichao Tu
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
- Department of Marine Sciences, Ocean College, Zhejiang University , Zhejiang, China
| | - Jianjun Wang
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences , Nanjing 210008, China
| | - Christopher W Schadt
- Biosciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Matthew W Fields
- Center for Biofilm Engineering, Montana State University , Bozeman, Montana 59717, United States
| | - Terry C Hazen
- Biosciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
- Department of Civil and Environmental Engineering, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Adam P Arkin
- Physical Biosciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - David A Stahl
- Department of Civil and Environmental Engineering, University of Washington , Seattle, Washington 98105, United States
| | - Jizhong Zhou
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, and School of Civil Engineering and Environmental Sciences, University of Oklahoma , Norman, Oklahoma 73019, United States
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University , Beijing 100084, China
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25
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Alexandratos VG, Behrends T, Van Cappellen P. Fate of Adsorbed U(VI) during Sulfidization of Lepidocrocite and Hematite. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:2140-2150. [PMID: 28121137 PMCID: PMC5343554 DOI: 10.1021/acs.est.6b05453] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 01/24/2017] [Accepted: 01/25/2017] [Indexed: 05/23/2023]
Abstract
The impact on U(VI) adsorbed to lepidocrocite (γ-FeOOH) and hematite (α-Fe2O3) was assessed when exposed to aqueous sulfide (S(-II)aq) at pH 8.0. With both minerals, competition between S(-II) and U(VI) for surface sites caused instantaneous release of adsorbed U(VI). Compared to lepidocrocite, consumption of S(-II)aq proceeded slower with hematite, but yielded maximum dissolved U concentrations that were more than 10 times higher, representing about one-third of the initially adsorbed U. Prolonged presence of S(-II)aq in experiments with hematite in combination with a larger release of adsorbed U(VI), enhanced the reduction of U(VI): after 24 h of reaction about 60-70% of U was in the form of U(IV), much higher than the 25% detected in the lepidocrocite suspensions. X-ray absorption spectra indicated that U(IV) in both hematite and lepidocrocite suspensions was not in the form of uraninite (UO2). Upon exposure to oxygen only part of U(IV) reoxidized, suggesting that monomeric U(IV) might have become incorporated in newly formed iron precipitates. Hence, sulfidization of Fe oxides can have diverse consequences for U mobility: in short-term, desorption of U(VI) increases U mobility, while reduction to U(IV) and its possible incorporation in Fe transformation products may lead to long-term U immobilization.
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Affiliation(s)
- Vasso G. Alexandratos
- Faculty
of Geosciences, Utrecht University, P.O. Box 80.021, 3508 TA Utrecht, The Netherlands
| | - Thilo Behrends
- Faculty
of Geosciences, Utrecht University, P.O. Box 80.021, 3508 TA Utrecht, The Netherlands
| | - Philippe Van Cappellen
- Ecohydrology
Research Group, Water Institute and Department of Earth and Environmental
Sciences University of Waterloo, 200 University Avenue West, Waterloo Ontario Canada
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A Highly Expressed High-Molecular-Weight S-Layer Complex of Pelosinus sp. Strain UFO1 Binds Uranium. Appl Environ Microbiol 2017; 83:AEM.03044-16. [PMID: 27913415 DOI: 10.1128/aem.03044-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 11/20/2016] [Indexed: 12/13/2022] Open
Abstract
Cell suspensions of Pelosinus sp. strain UFO1 were previously shown, using spectroscopic analysis, to sequester uranium as U(IV) complexed with carboxyl and phosphoryl group ligands on proteins. The goal of our present study was to characterize the proteins involved in uranium binding. Virtually all of the uranium in UFO1 cells was associated with a heterodimeric protein, which was termed the uranium-binding complex (UBC). The UBC was composed of two S-layer domain proteins encoded by UFO1_4202 and UFO1_4203. Samples of UBC purified from the membrane fraction contained 3.3 U atoms/heterodimer, but significant amounts of phosphate were not detected. The UBC had an estimated molecular mass by gel filtration chromatography of 15 MDa, and it was proposed to contain 150 heterodimers (UFO1_4203 and UFO1_4202) and about 500 uranium atoms. The UBC was also the dominant extracellular protein, but when purified from the growth medium, it contained only 0.3 U atoms/heterodimer. The two genes encoding the UBC were among the most highly expressed genes within the UFO1 genome, and their expressions were unchanged by the presence or absence of uranium. Therefore, the UBC appears to be constitutively expressed and is the first line of defense against uranium, including by secretion into the extracellular medium. Although S-layer proteins were previously shown to bind U(VI), here we showed that U(IV) binds to S-layer proteins, we identified the proteins involved, and we quantitated the amount of uranium bound. IMPORTANCE Widespread uranium contamination from industrial sources poses hazards to human health and to the environment. Herein, we identified a highly abundant uranium-binding complex (UBC) from Pelosinus sp. strain UFO1. The complex makes up the primary protein component of the S-layer of strain UFO1 and binds 3.3 atoms of U(IV) per heterodimer. While other bacteria have been shown to bind U(VI) on their S-layer, we demonstrate here an example of U(IV) bound by an S-layer complex. The UBC provides a potential tool for the microbiological sequestration of uranium for the cleaning of contaminated environments.
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27
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Majumder ELW, Wall JD. Uranium Bio-Transformations: Chemical or Biological Processes? ACTA ACUST UNITED AC 2017. [DOI: 10.4236/ojic.2017.72003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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28
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Chen A, Shang C, Shao J, Zhang J, Huang H. The application of iron-based technologies in uranium remediation: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 575:1291-1306. [PMID: 27720254 DOI: 10.1016/j.scitotenv.2016.09.211] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 09/25/2016] [Accepted: 09/26/2016] [Indexed: 06/06/2023]
Abstract
Remediating uranium contamination is of worldwide interest because of the increasing release of uranium from mining and processing, nuclear power leaks, depleted uranium components in weapons production and disposal, and phosphate fertilizer in agriculture activities. Iron-based technologies are attractive because they are highly efficient, inexpensive, and readily available. This paper provides an overview of the current literature that addresses the application of iron-based technologies in the remediation of sites with elevated uranium levels. The application of iron-based materials, the current remediation technologies and mechanisms, and the effectiveness and environmental safety considerations of these approaches were discussed. Because uranium can be reduced and reoxidized in the environment, the review also proposes strategies for long-term in situ remediation of uranium. Unfortunately, iron-based materials (nanoscale zerovalent iron and iron oxides) can be toxic to microorganisms. As such, further studies exploring the links among the fates, ecological impacts, and other environmentally relevant factors are needed to better understand the constraints on using iron-based technologies for remediation.
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Affiliation(s)
- Anwei Chen
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Cui Shang
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Jihai Shao
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China.
| | - Jiachao Zhang
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Hongli Huang
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
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29
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Li D, Egodawatte S, Kaplan DI, Larsen SC, Serkiz SM, Seaman JC. Functionalized magnetic mesoporous silica nanoparticles for U removal from low and high pH groundwater. JOURNAL OF HAZARDOUS MATERIALS 2016; 317:494-502. [PMID: 27341378 DOI: 10.1016/j.jhazmat.2016.05.093] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/26/2016] [Accepted: 05/31/2016] [Indexed: 06/06/2023]
Abstract
U(VI) species display limited adsorption onto sediment minerals and synthetic sorbents in pH <4 or pH >8 groundwater. In this work, magnetic mesoporous silica nanoparticles (MMSNs) with magnetite nanoparticle cores were functionalized with various organic molecules using post-synthetic methods. The functionalized MMSNs were characterized using N2 adsorption-desorption isotherms, thermogravimetric analysis (TGA), transmission electron microscopy (TEM), (13)C cross polarization and magic angle spinning (CPMAS) nuclear magnetic resonance (NMR) spectroscopy, and powder X-ray diffraction (XRD), which indicated that mesoporous silica (MCM-41) particles of 100-200nm formed around a core of magnetic iron oxide, and the functional groups were primarily grafted into the mesopores of ∼3.0nm in size. The functionalized MMSNs were effective for U removal from pH 3.5 and 9.6 artificial groundwater (AGW). Functionalized MMSNs removed U from the pH 3.5 AGW by as much as 6 orders of magnitude more than unfunctionalized nanoparticles or silica and had adsorption capacities as high as 38mg/g. They removed U from the pH 9.6 AGW as much as 4 orders of magnitude greater than silica and 2 orders of magnitude greater than the unfunctionalized nanoparticles with adsorption capacities as high as 133mg/g. These results provide an applied solution for treating U contamination that occurs at extreme pH environments and a scientific foundation for solving critical industrial issues related to environmental stewardship and nuclear power production.
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Affiliation(s)
- Dien Li
- Savannah River National Laboratory, Aiken, SC 29808, USA.
| | - Shani Egodawatte
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA
| | | | - Sarah C Larsen
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA
| | - Steven M Serkiz
- Savannah River National Laboratory, Aiken, SC 29808, USA; Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA
| | - John C Seaman
- Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA
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30
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Koster van Groos PG, Kaplan DI, Chang HS, Seaman JC, Li D, Peacock AD, Scheckel KG, Jaffé PR. Uranium fate in wetland mesocosms: Effects of plants at two iron loadings with different pH values. CHEMOSPHERE 2016; 163:116-124. [PMID: 27522183 PMCID: PMC7307573 DOI: 10.1016/j.chemosphere.2016.08.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 07/31/2016] [Accepted: 08/01/2016] [Indexed: 06/06/2023]
Abstract
Small-scale continuous flow wetland mesocosms (∼0.8 L) were used to evaluate how plant roots under different iron loadings affect uranium (U) mobility. When significant concentrations of ferrous iron (Fe) were present at circumneutral pH values, U concentrations in root exposed sediments were an order of magnitude greater than concentrations in root excluded sediments. Micro X-ray absorption near-edge structure (μ-XANES) spectroscopy indicated that U was associated with the plant roots primarily as U(VI) or U(V), with limited evidence of U(IV). Micro X-ray fluorescence (μ-XRF) of plant roots suggested that for high iron loading at circumneutral pH, U was co-located with Fe, perhaps co-precipitated with root Fe plaques, while for low iron loading at a pH of ∼4 the correlation between U and Fe was not significant, consistent with previous observations of U associated with organic matter. Quantitative PCR analyses indicated that the root exposed sediments also contained elevated numbers of Geobacter spp., which are likely associated with enhanced iron cycling, but may also reduce mobile U(VI) to less mobile U(IV) species.
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Affiliation(s)
| | | | - Hyun-Shik Chang
- Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA
| | - John C Seaman
- Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA
| | - Dien Li
- Savannah River National Laboratory, Aiken, SC 29808, USA
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31
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Şengör SS, Singh G, Dohnalkova A, Spycher N, Ginn TR, Peyton BM, Sani RK. Impact of different environmental conditions on the aggregation of biogenic U(IV) nanoparticles synthesized by Desulfovibrio alaskensis G20. Biometals 2016; 29:965-980. [PMID: 27623995 DOI: 10.1007/s10534-016-9969-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 08/31/2016] [Indexed: 11/25/2022]
Abstract
This study investigates the impact of specific environmental conditions on the formation of colloidal U(IV) nanoparticles by the sulfate reducing bacteria (SRB, Desulfovibrio alaskensis G20). The reduction of soluble U(VI) to less soluble U(IV) was quantitatively investigated under growth and non-growth conditions in bicarbonate or 1,4-piperazinediethanesulfonic acid (PIPES) buffered environments. The results showed that under non-growth conditions, the majority of the reduced U nanoparticles aggregated and precipitated out of solution. High resolution transmission electron microscopy revealed that only a very small fraction of cells had reduced U precipitates in the periplasmic spaces in the presence of PIPES buffer, whereas in the presence of bicarbonate buffer, reduced U was also observed in the cytoplasm with greater aggregation of biogenic U(IV) particles at higher initial U(VI) concentrations. The same experiments were repeated under growth conditions using two different electron donors (lactate and pyruvate) and three electron acceptors (sulfate, fumarate, and thiosulfate). In contrast to the results of the non-growth experiments, even after 0.2 μm filtration, the majority of biogenic U(IV) remained in the aqueous phase resulting in potentially mobile biogenic U(IV) nanoparticles. Size fractionation results showed that U(IV) aggregates were between 18 and 200 nm in diameter, and thus could be very mobile. The findings of this study are helpful to assess the size and potential mobility of reduced U nanoparticles under different environmental conditions, and would provide insights on their potential impact affecting U(VI) bioremediation efforts at subsurface contaminated sites.
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Affiliation(s)
- S Sevinç Şengör
- Department of Civil and Environmental Engineering, Southern Methodist University, Dallas, TX, 75275-0339, USA
| | - Gursharan Singh
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, 501 East St. Joseph Street, Rapid City, SD, 57701-3995, USA
| | - Alice Dohnalkova
- WR Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Nicolas Spycher
- Lawrence Berkeley National Laboratory, Earth Sciences Division, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
| | - Timothy R Ginn
- Department of Civil and Environmental Engineering, Washington State University, 405 Spokane Street, Pullman, WA, 99164, USA
| | - Brent M Peyton
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, 59715, USA
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, 501 East St. Joseph Street, Rapid City, SD, 57701-3995, USA.
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32
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Hu N, Ding DX, Li SM, Tan X, Li GY, Wang YD, Xu F. Bioreduction of U(VI) and stability of immobilized uranium under suboxic conditions. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 154:60-67. [PMID: 26854555 DOI: 10.1016/j.jenvrad.2016.01.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 01/28/2016] [Accepted: 01/28/2016] [Indexed: 06/05/2023]
Abstract
In order to study the bioreduction of U(VI) and stability of immobilized uranium under suboxic conditions, microcosm were amended with ethanol, lactate and glucose, and incubated under suboxic conditions. During the incubation, total dissolved U in amended microcosms decreased from 0.95 mg/L to 0.03 mg/L. Pyrosequencing results showed that, the proportion of anaerobic microorganisms capable of reducing U(VI) under suboxic conditions was small compared with that under anoxic conditions; the proportion of aerobic and facultative anaerobic microorganisms capable of consuming the dissolved oxygen was large; and some of the facultative anaerobic microorganisms could reduce U(VI). These results indicated that different microbial communities were responsible for the bioreduction of U(VI) under suboxic and anoxic conditions. After the electron donors were exhausted, total dissolved U in the amended microcosms remained unchanged, while the U(VI)/U(IV) ratio in the solid phase of sediments increased obviously. This implied that the performance of bioreduction of the U(VI) can be maintained under suboxic condition.
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Affiliation(s)
- Nan Hu
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, PR China
| | - De-xin Ding
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, PR China.
| | - Shi-mi Li
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, PR China
| | - Xiang Tan
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, PR China
| | - Guang-yue Li
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, PR China
| | - Yong-dong Wang
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, PR China
| | - Fei Xu
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, PR China
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Wang L, Burns S, Giammar DE, Fortner JD. Element mobilization from Bakken shales as a function of water chemistry. CHEMOSPHERE 2016; 149:286-293. [PMID: 26866966 DOI: 10.1016/j.chemosphere.2016.01.107] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 01/24/2016] [Accepted: 01/25/2016] [Indexed: 06/05/2023]
Abstract
Waters that return to the surface after injection of a hydraulic fracturing fluid for gas and oil production contain elements, including regulated metals and metalloids, which are mobilized through interactions between the fracturing fluid and the shale formation. The rate and extent of mobilization depends on the geochemistry of the formation and the chemical characteristics of the fracturing fluid. In this work, laboratory scale experiments investigated the influence of water chemistry on element mobilization from core samples taken from the Bakken formation, one of the most productive shale oil plays in the US. Fluid properties were systematically varied and evaluated with regard to pH, oxidant level, solid:water ratio, temperature, and chemical additives. Element mobilization strongly depended on solution pH and redox conditions and to a lesser extent on the temperature and solid:water ratio. The presence of oxygen and addition of hydrogen peroxide or ammonium persulfate led to pyrite oxidation, resulting in elevated sulfate concentrations. Further, depending on the mineral carbonates available to buffer the system pH, pyrite oxidation could lower the system pH and enhance the mobility of several metals and metalloids.
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Affiliation(s)
- Lin Wang
- Washington University in St. Louis, Department of Energy, Environmental, and Chemical Engineering, Campus Box 1180, One Brookings Drive, St. Louis, MO 631C30, United States
| | - Scott Burns
- Washington University in St. Louis, Department of Energy, Environmental, and Chemical Engineering, Campus Box 1180, One Brookings Drive, St. Louis, MO 631C30, United States
| | - Daniel E Giammar
- Washington University in St. Louis, Department of Energy, Environmental, and Chemical Engineering, Campus Box 1180, One Brookings Drive, St. Louis, MO 631C30, United States.
| | - John D Fortner
- Washington University in St. Louis, Department of Energy, Environmental, and Chemical Engineering, Campus Box 1180, One Brookings Drive, St. Louis, MO 631C30, United States.
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Paradis CJ, Jagadamma S, Watson DB, McKay LD, Hazen TC, Park M, Istok JD. In situ mobility of uranium in the presence of nitrate following sulfate-reducing conditions. JOURNAL OF CONTAMINANT HYDROLOGY 2016; 187:55-64. [PMID: 26897652 DOI: 10.1016/j.jconhyd.2016.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 02/03/2016] [Accepted: 02/08/2016] [Indexed: 06/05/2023]
Abstract
Reoxidation and mobilization of previously reduced and immobilized uranium by dissolved-phase oxidants poses a significant challenge for remediating uranium-contaminated groundwater. Preferential oxidation of reduced sulfur-bearing species, as opposed to reduced uranium-bearing species, has been demonstrated to limit the mobility of uranium at the laboratory scale yet field-scale investigations are lacking. In this study, the mobility of uranium in the presence of nitrate oxidant was investigated in a shallow groundwater system after establishing conditions conducive to uranium reduction and the formation of reduced sulfur-bearing species. A series of three injections of groundwater (200 L) containing U(VI) (5 μM) and amended with ethanol (40 mM) and sulfate (20 mM) were conducted in ten test wells in order to stimulate microbial-mediated reduction of uranium and the formation of reduced sulfur-bearing species. Simultaneous push-pull tests were then conducted in triplicate well clusters to investigate the mobility of U(VI) under three conditions: 1) high nitrate (120 mM), 2) high nitrate (120 mM) with ethanol (30 mM), and 3) low nitrate (2 mM) with ethanol (30 mM). Dilution-adjusted breakthrough curves of ethanol, nitrate, nitrite, sulfate, and U(VI) suggested that nitrate reduction was predominantly coupled to the oxidation of reduced-sulfur bearing species, as opposed to the reoxidation of U(IV), under all three conditions for the duration of the 36-day tests. The amount of sulfate, but not U(VI), recovered during the push-pull tests was substantially more than injected, relative to bromide tracer, under all three conditions and further suggested that reduced sulfur-bearing species were preferentially oxidized under nitrate-reducing conditions. However, some reoxidation of U(IV) was observed under nitrate-reducing conditions and in the absence of detectable nitrate and/or nitrite. This suggested that reduced sulfur-bearing species may not be fully effective at limiting the mobility of uranium in the presence of dissolved and/or solid-phase oxidants. The results of this field study confirmed those of previous laboratory studies which suggested that reoxidation of uranium under nitrate-reducing conditions can be substantially limited by preferential oxidation of reduced sulfur-bearing species.
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Affiliation(s)
- Charles J Paradis
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996, United States.
| | - Sindhu Jagadamma
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, United States
| | - David B Watson
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, United States
| | - Larry D McKay
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996, United States
| | - Terry C Hazen
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996, United States; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, United States; Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States; Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, United States; Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, United States; Institute for a Secure and Sustainable Environment, University of Tennessee, Knoxville, TN 37996, United States
| | - Melora Park
- School of Civil and Construction Engineering, Oregon State University, Corvallis, OR 97331, United States
| | - Jonathan D Istok
- School of Civil and Construction Engineering, Oregon State University, Corvallis, OR 97331, United States
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The Role of Bacterial Spores in Metal Cycling and Their Potential Application in Metal Contaminant Bioremediation. Microbiol Spectr 2016; 4. [DOI: 10.1128/microbiolspec.tbs-0018-2013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
ABSTRACT
Bacteria are one of the premier biological forces that, in combination with chemical and physical forces, drive metal availability in the environment. Bacterial spores, when found in the environment, are often considered to be dormant and metabolically inactive, in a resting state waiting for favorable conditions for them to germinate. However, this is a highly oversimplified view of spores in the environment. The surface of bacterial spores represents a potential site for chemical reactions to occur. Additionally, proteins in the outer layers (spore coats or exosporium) may also have more specific catalytic activity. As a consequence, bacterial spores can play a role in geochemical processes and may indeed find uses in various biotechnological applications. The aim of this review is to introduce the role of bacteria and bacterial spores in biogeochemical cycles and their potential use as toxic metal bioremediation agents.
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Hidouri S. Possible domestication of uranium oxides using biological assistance reduction. Saudi J Biol Sci 2015; 24:1-10. [PMID: 28053564 PMCID: PMC5198920 DOI: 10.1016/j.sjbs.2015.09.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 09/03/2015] [Accepted: 09/06/2015] [Indexed: 11/27/2022] Open
Abstract
Uranium has been defined in material research engineering field as one of the most energetic radioactive elements in the entire Mendeleev periodic table. The manipulation of uranium needs higher theories and sophisticated apparatus even in nuclear energy extraction or in many other chemical applications. Above the nuclear exploitation level, the chemical conventional approaches used, require a higher temperature and pressure to control the destination of ionic form. However, it has been discovered later that at biological scale, the manipulation of this actinide is possible under friendly conditions. The review summarizes the relevant properties of uranium element and a brief characterization of nanoparticles, based on some structural techniques. These techniques reveal the common link between chemical approaches and biological assistance in nanoparticles. Also, those biological entities have been able to get it after reduction. Uranium is known for its ability to destroy ductile materials. So, if biological cell can really reduce uranium, then how does it work?
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Affiliation(s)
- Slah Hidouri
- Department of Research in Sciences of Life and Materials, B6 Section, Faculty of Sciences of Bizerte, Carthage University, Jarzouna 7021, Tunisia
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Stewart BD, Cismasu AC, Williams KH, Peyton BM, Nico PS. Reactivity of Uranium and Ferrous Iron with Natural Iron Oxyhydroxides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:10357-10365. [PMID: 26226398 DOI: 10.1021/acs.est.5b02645] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Determining key reaction pathways involving uranium and iron oxyhydroxides under oxic and anoxic conditions is essential for understanding uranium mobility as well as other iron oxyhydroxide mediated processes, particularly near redox boundaries where redox conditions change rapidly in time and space. Here we examine the reactivity of a ferrihydrite-rich sediment from a surface seep adjacent to a redox boundary at the Rifle, Colorado field site. Iron(II)-sediment incubation experiments indicate that the natural ferrihydrite fraction of the sediment is not susceptible to reductive transformation under conditions that trigger significant mineralogical transformations of synthetic ferrihydrite. No measurable Fe(II)-promoted transformation was observed when the Rifle sediment was exposed to 30 mM Fe(II) for up to 2 weeks. Incubation of the Rifle sediment with 3 mM Fe(II) and 0.2 mM U(VI) for 15 days shows no measurable incorporation of U(VI) into the mineral structure or reduction of U(VI) to U(IV). Results indicate a significantly decreased reactivity of naturally occurring Fe oxyhydroxides as compared to synthetic minerals, likely due to the association of impurities (e.g., Si, organic matter), with implications for the mobility and bioavailability of uranium and other associated species in field environments.
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Affiliation(s)
- Brandy D Stewart
- Chemical and Biological Engineering, Montana State University , Bozeman, Montana 59717, United States
| | - A Cristina Cismasu
- Lawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, California 94720, United States
| | - Kenneth H Williams
- Lawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, California 94720, United States
| | - Brent M Peyton
- Chemical and Biological Engineering, Montana State University , Bozeman, Montana 59717, United States
| | - Peter S Nico
- Lawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, California 94720, United States
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Mouser PJ, N'Guessan LA, Qafoku NP, Sinha M, Williams KH, Dangelmayr M, Resch CT, Peacock A, Wang Z, Figueroa L, Long PE. Influence of Carbon and Microbial Community Priming on the Attenuation of Uranium in a Contaminated Floodplain Aquifer. GROUND WATER 2015; 53:600-613. [PMID: 25047748 DOI: 10.1111/gwat.12238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 06/01/2014] [Indexed: 06/03/2023]
Abstract
The capacity for subsurface sediments to sequester radionuclide contaminants, such as uranium (U), and retain them after bioremediation efforts are completed is critical to the long-term stewardship of re-mediated sites. In U bioremediation strategies, carbon amendment stimulates bioreduction of U(VI) to U(IV), immobilizing it within the sediments. Sediments enriched in natural organic matter are naturally capable of sequestering significant U, but may serve as sources to the aquifer, contributing to plume persistence. Two types of organic-rich sediments were compared to better understand U release mechanisms. Sediments that were artificially primed for U removal were retrieved from an area previously biostimulated while detrital-rich sediments were collected from a location never subject to amendment. Batch incubations demonstrated that primed sediments rapidly removed uranium from the groundwater, whereas naturally reduced sediments released a sizeable portion of U before U(VI)-reduction commenced. Column experiments confirmed that U release persisted for 65 pore volumes in naturally reduced sediments, demonstrating their sink-source behavior. Acetate addition to primed sediments shifted the microbial community from sulfate-reducing bacteria within Desulfobacteraceae to the iron-reducing Geobacteraceae and Firmicutes, associated with efficient U(VI) removal and retention, respectively. In contrast, Geobacteraceae communities in naturally reduced sediments were replaced by sequences with similarity to Pseudomonas spp. during U release, while U(VI) removal only occurred with enrichment of Firmicutes. These investigations stress the importance of characterizing zones with heterogeneous carbon pools at U-contaminated sites prior to the determination of a remedial strategy to identify areas, which may contribute to long-term sourcing of the contaminants.
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Affiliation(s)
| | - L A N'Guessan
- Pacific Northwest National Laboratory, Richland, WA 99352
- Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - N P Qafoku
- Pacific Northwest National Laboratory, Richland, WA 99352
| | - M Sinha
- Pacific Northwest National Laboratory, Richland, WA 99352
- Environmental Science and Engineering, Colorado School of Mines, Golden, CO 80401
| | | | | | - C T Resch
- Pacific Northwest National Laboratory, Richland, WA 99352
| | - A Peacock
- Washington State University, Richland, WA 99354
| | - Z Wang
- Pacific Northwest National Laboratory, Richland, WA 99352
| | | | - P E Long
- Microbial Insights, Rockford, TN 37853
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Dynamic Succession of Groundwater Functional Microbial Communities in Response to Emulsified Vegetable Oil Amendment during Sustained In Situ U(VI) Reduction. Appl Environ Microbiol 2015; 81:4164-72. [PMID: 25862231 DOI: 10.1128/aem.00043-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 04/05/2015] [Indexed: 11/20/2022] Open
Abstract
A pilot-scale field experiment demonstrated that a one-time amendment of emulsified vegetable oil (EVO) reduced groundwater U(VI) concentrations for 1 year in a fast-flowing aquifer. However, little is known about how EVO amendment stimulates the functional gene composition, structure, and dynamics of groundwater microbial communities toward prolonged U(VI) reduction. In this study, we hypothesized that EVO amendment would shift the functional gene composition and structure of groundwater microbial communities and stimulate key functional genes/groups involved in EVO biodegradation and reduction of electron acceptors in the aquifer. To test these hypotheses, groundwater microbial communities after EVO amendment were analyzed using a comprehensive functional gene microarray. Our results showed that EVO amendment stimulated sequential shifts in the functional composition and structure of groundwater microbial communities. Particularly, the relative abundance of key functional genes/groups involved in EVO biodegradation and the reduction of NO3 (-), Mn(IV), Fe(III), U(VI), and SO4 (2-) significantly increased, especially during the active U(VI) reduction period. The relative abundance for some of these key functional genes/groups remained elevated over 9 months. Montel tests suggested that the dynamics in the abundance, composition, and structure of these key functional genes/groups were significantly correlated with groundwater concentrations of acetate, NO3 (-), Mn(II), Fe(II), U(VI), and SO4 (2-). Our results suggest that EVO amendment stimulated dynamic succession of key functional microbial communities. This study improves our understanding of the composition, structure, and function changes needed for groundwater microbial communities to sustain a long-term U(VI) reduction.
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High-Quality Draft Genome Sequence of Desulfovibrio carbinoliphilus FW-101-2B, an Organic Acid-Oxidizing Sulfate-Reducing Bacterium Isolated from Uranium(VI)-Contaminated Groundwater. GENOME ANNOUNCEMENTS 2015; 3:3/2/e00092-15. [PMID: 25767232 PMCID: PMC4357754 DOI: 10.1128/genomea.00092-15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Desulfovibrio carbinoliphilus subsp. oakridgensis FW-101-2B is an anaerobic, organic acid/alcohol-oxidizing, sulfate-reducing δ-proteobacterium. FW-101-2B was isolated from contaminated groundwater at The Field Research Center at Oak Ridge National Lab after in situ stimulation for heavy metal-reducing conditions. The genome will help elucidate the metabolic potential of sulfate-reducing bacteria during uranium reduction.
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Li D, Kaplan DI, Chang HS, Seaman JC, Jaffé PR, Koster van Groos P, Scheckel KG, Segre CU, Chen N, Jiang DT, Newville M, Lanzirotti A. Spectroscopic evidence of uranium immobilization in acidic wetlands by natural organic matter and plant roots. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2823-2832. [PMID: 25634067 DOI: 10.1021/es505369g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Biogeochemistry of uranium in wetlands plays important roles in U immobilization in storage ponds of U mining and processing facilities but has not been well understood. The objective of this work was to study molecular mechanisms responsible for high U retention by Savannah River Site (SRS) wetland sediments under varying redox and acidic (pH = 2.6-5.8) conditions using U L3-edge X-ray absorption spectroscopy. Uranium in the SRS wetland sediments existed primarily as U(VI) bonded as a bidentate to carboxylic sites (U-C bond distance at ∼2.88 Å), rather than phenolic or other sites of natural organic matter (NOM). In microcosms simulating the SRS wetland processes, U immobilization on roots was 2 orders of magnitude higher than on the adjacent brown or more distant white sands in which U was U(VI). Uranium on the roots were both U(IV) and U(VI), which were bonded as a bidentate to carbon, but the U(VI) may also form a U phosphate mineral. After 140 days of air exposure, all U(IV) was reoxidized to U(VI) but remained as a bidentate bonding to carbon. This study demonstrated NOM and plant roots can highly immobilize U(VI) in the SRS acidic sediments, which has significant implication for the long-term stewardship of U-contaminated wetlands.
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Affiliation(s)
- Dien Li
- Savannah River National Laboratory, Aiken, South Carolina 29808, United States
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Complete Genome Sequence of Anaeromyxobacter sp. Fw109-5, an Anaerobic, Metal-Reducing Bacterium Isolated from a Contaminated Subsurface Environment. GENOME ANNOUNCEMENTS 2015; 3:3/1/e01449-14. [PMID: 25614562 PMCID: PMC4319575 DOI: 10.1128/genomea.01449-14] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We report the genome sequence of Anaeromyxobacter sp. Fw109-5, isolated from nitrate- and uranium-contaminated subsurface sediment of the Oak Ridge Integrated Field-Scale Subsurface Research Challenge (IFC) site, Oak Ridge Reservation, TN. The bacterium’s genome sequence will elucidate its physiological potential in subsurface sediments undergoing in situ uranium bioremediation and natural attenuation.
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43
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Luan F, Zhang G, Senko JM, Burgos WD. Effects of supplemental organic carbon on long-term reduction and reoxidation of uranium. RSC Adv 2015. [DOI: 10.1039/c5ra02550h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Higher concentration of ethanol supported more extensive sulfate reduction to sulfide, which protected biogenic UO2from oxidants reoxidation.
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Affiliation(s)
- Fubo Luan
- Department of Civil and Environmental Engineering
- The Pennsylvania State University
- University Park
- USA
| | - Gengxin Zhang
- Institute of Tibetan Research
- Chinese Academy of Sciences
- Beijing
- China
| | - John M. Senko
- Department of Geosciences and Department of Biology
- The University of Akron
- Akron
- USA
| | - William D. Burgos
- Department of Civil and Environmental Engineering
- The Pennsylvania State University
- University Park
- USA
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Troyer LD, Tang Y, Borch T. Simultaneous reduction of arsenic(V) and uranium(VI) by mackinawite: role of uranyl arsenate precipitate formation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:14326-14334. [PMID: 25383895 DOI: 10.1021/es5037496] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Uranium (U) and arsenic (As) often occur together naturally and, as a result, can be co-contaminants at sites of uranium mining and processing, yet few studies have examined the simultaneous redox dynamics of U and As. This study examines the influence of arsenate (As(V)) on the reduction of uranyl (U(VI)) by the redox-active mineral mackinawite (FeS). As(V) was added to systems containing 47 or 470 μM U(VI) at concentrations ranging from 0 to 640 μM. In the absence of As(V), U was completely removed from solution and fully reduced to nano-uraninite (nano-UO2). While the addition of As(V) did not reduce U uptake, at As(V) concentrations above 320 μM, the reduction of U(VI) was limited due to the formation of a trögerite-like uranyl arsenate precipitate. The presence of U also significantly inhibited As(V) reduction. While less U(VI) reduction to nano-UO2 may take place in systems with high As(V) concentrations, formation of trögerite-like mineral phases may be an acceptable reclamation end point due to their high stability under oxic conditions.
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Affiliation(s)
- Lyndsay D Troyer
- Department of Chemistry, Colorado State University , 1872 Campus Delivery, Fort Collins, Colorado 80523, United States
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Bi Y, Hayes KF. Surface passivation limited UO2 oxidative dissolution in the presence of FeS. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:13402-13411. [PMID: 25322064 DOI: 10.1021/es5041392] [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
Iron sulfide minerals produced during in situ bioremediation of U can serve as an oxygen scavenger to retard uraninite (UO2) oxidation upon oxygen intrusion. Under persistent oxygen supply, however, iron sulfides become oxidized and depleted, giving rise to elevated dissolved oxygen (DO) levels and remobilization of U(IV). The present study investigated the mechanism that regulates UO2 oxidative dissolution rate in a flow-through system when oxygen breakthrough occurred as a function of mackinawite (FeS) and carbonate concentrations. The formation and evolution of surface layers on UO2 were characterized using XAS and XPS. During FeS inhibition period, the continuous supply of carbonate and calcium in the influent effectively complexed and removed oxidized U(VI) to preserve an intermediate U4O9 surface. When the FeS became depleted by oxidization, a transient, rapid dissolution of UO2 was observed along with DO breakthrough in the reactor. This rate was greater than during the preceding FeS inhibition period and control experiments in the absence of FeS. With increasing DO, the rate slowed and the rate-limiting step shifted from surface oxidation to U(VI) detachment as U(VI) passivation layers developed. In contrast, increasing the carbonate concentrations facilitated detachment of surface-associated U(VI) complexes and impeded the formation of U(VI) passivation layer. This study demonstrates the critical role of U(VI) surface layer formation versus U(VI) detachment in controlling UO2 oxidative dissolution rate during periods of variable oxygen presence under simulated groundwater conditions.
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Affiliation(s)
- Yuqiang Bi
- Department of Civil and Environmental Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
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Bioreduction of U(VI) in groundwater under anoxic conditions from a decommissioned in situ leaching uranium mine. Bioprocess Biosyst Eng 2014; 38:661-9. [DOI: 10.1007/s00449-014-1305-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Accepted: 10/09/2014] [Indexed: 10/24/2022]
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Massey MS, Lezama-Pacheco JS, Michel FM, Fendorf S. Uranium incorporation into aluminum-substituted ferrihydrite during iron(ii)-induced transformation. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2014; 16:2137-2144. [PMID: 25124142 DOI: 10.1039/c4em00148f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Uranium retention processes (adsorption, precipitation, and incorporation into host minerals) exert strong controls on U mobility in the environment, and understanding U retention is therefore crucial for predicting the migration of U within surface and groundwater. Uranium can be incorporated into Fe (hydr)oxides during Fe(ii)-induced transformation of ferrihydrite to goethite. However, ferrihydrite seldom exists as a pure phase within soils or sediments, and structural impurities such as Al alter its reactivity. The presence of Al in ferrihydrite, for example, decreases the rate of transformation to goethite, and thus may impact the retention pathway, or extent of retention, of U. Here, we investigate the extent and pathways of U(vi) retention on Al-ferrihydrite during Fe(ii)-induced transformation. Ferrihydrite containing 0%, 1%, 5%, 10%, and 20% Al was reacted with 10 μM U and 300 μM Fe(ii) in the presence of 0 mM and 4 mM Ca(2+) and 3.8 mM carbonate at pH 7.0. Solid reaction products were characterized using U L3-edge EXAFS spectroscopy to differentiate between adsorbed U and U incorporated into the goethite lattice. Uranium incorporation into Al-ferrihydrite declined from ∼70% of solid-phase U at 0% and 1% Al to ∼30% of solid phase U at 20% Al content. The decrease in U incorporation with increasing Al concentration was due to two main factors: (1) decreased transformation of ferrihydrite to goethite; and, (2) a decrease of the goethite lattice with increasing Al, making the lattice less compatible with large U atoms. However, uranium incorporation can occur even with an Al-substituted ferrihydrite precursor in the presence or absence of Ca(2+). The process of U incorporation into Al-goethite may therefore be a potential long-term sink of U in subsurface environments where Al-substituted iron oxides are common, albeit at lower levels of incorporation with increasing Al content.
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Affiliation(s)
- Michael S Massey
- Department of Environmental & Earth System Science, Stanford University, Stanford, California 94305, USA
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Abstract
Worldwide industrialization activities create vast amounts of organic and inorganic waste streams that frequently result in significant soil and groundwater contamination. Metals and radionuclides are of particular concern due to their mobility and long-term persistence in aquatic and terrestrial environments. As the global population increases, the demand for safe, contaminant-free soil and groundwater will increase as will the need for effective and inexpensive remediation strategies. Remediation strategies that include physical and chemical methods (i.e., abiotic) or biological activities have been shown to impede the migration of radionuclide and metal contaminants within soil and groundwater. However, abiotic remediation methods are often too costly owing to the quantities and volumes of soils and/or groundwater requiring treatment. The in situ sequestration of metals and radionuclides mediated by biological activities associated with microbial phosphorus metabolism is a promising and less costly addition to our existing remediation methods. This review highlights the current strategies for abiotic and microbial phosphate-mediated techniques for uranium and metal remediation.
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Chang HS, Buettner SW, Seaman JC, Jaffé PR, van Groos PGK, Li D, Peacock AD, Scheckel KG, Kaplan DI. Uranium immobilization in an iron-rich rhizosphere of a native wetland plant from the Savannah River Site under reducing conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:9270-9278. [PMID: 25051143 DOI: 10.1021/es5015136] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The hypothesis of this study was that iron plaques formed on the roots of wetland plants and their rhizospheres create environmental conditions favorable for iron reducing bacteria that promote the in situ immobilization of uranium. Greenhouse microcosm studies were conducted using native plants (Sparganium americanum) from a wetland located on the Savannah River Site, Aiken, SC. After iron plaques were established during a 73-day period by using an anoxic Fe(II)-rich nutrient solution, a U(VI) amended nutrient solution was added to the system for an additional two months. Compared to plant-free control microcosms, microcosms containing iron plaques successfully stimulated the growth of targeted iron reducing bacteria, Geobacter spp. Their population continuously increased after the introduction of the U(VI) nutrient solution. The reduction of some of the U(VI) to U(IV) by iron reducing bacteria was deduced based on the observations that the aqueous Fe(II) concentrations increased while the U(VI) concentrations decreased. The Fe(II) produced by the iron reducing bacteria was assumed to be reoxidized by the oxygen released from the roots. Advanced spectroscopic analyses revealed that a significant fraction of the U(VI) had been reduced to U(IV) and they were commonly deposited in association with phosphorus on the iron plaque.
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Affiliation(s)
- Hyun-shik Chang
- Savannah River Ecology Laboratory, University of Georgia , P.O. Drawer E, Aiken, South Carolina 29802, United States
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50
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Holmes DE, Giloteaux L, Orellana R, Williams KH, Robbins MJ, Lovley DR. Methane production from protozoan endosymbionts following stimulation of microbial metabolism within subsurface sediments. Front Microbiol 2014; 5:366. [PMID: 25147543 PMCID: PMC4123621 DOI: 10.3389/fmicb.2014.00366] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 07/01/2014] [Indexed: 11/13/2022] Open
Abstract
Previous studies have suggested that protozoa prey on Fe(III)- and sulfate-reducing bacteria that are enriched when acetate is added to uranium contaminated subsurface sediments to stimulate U(VI) reduction. In order to determine whether protozoa continue to impact subsurface biogeochemistry after these acetate amendments have stopped, 18S rRNA and ß-tubulin sequences from this phase of an in situ uranium bioremediation field experiment were analyzed. Sequences most similar to Metopus species predominated, with the majority of sequences most closely related to M. palaeformis, a cilitated protozoan known to harbor methanogenic symbionts. Quantification of mcrA mRNA transcripts in the groundwater suggested that methanogens closely related to Metopus endosymbionts were metabolically active at this time. There was a strong correlation between the number of mcrA transcripts from the putative endosymbiotic methanogen and Metopus ß-tubulin mRNA transcripts during the course of the field experiment, suggesting that the activity of the methanogens was dependent upon the activity of the Metopus species. Addition of the eukaryotic inhibitors cyclohexamide and colchicine to laboratory incubations of acetate-amended subsurface sediments significantly inhibited methane production and there was a direct correlation between methane concentration and Metopus ß-tubulin and putative symbiont mcrA gene copies. These results suggest that, following the stimulation of subsurface microbial growth with acetate, protozoa harboring methanogenic endosymbionts become important members of the microbial community, feeding on moribund biomass and producing methane.
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Affiliation(s)
- Dawn E Holmes
- Department of Microbiology, University of Massachusetts Amherst, MA, USA ; Physical and Biological Sciences, Western New England University Springfield, MA, USA
| | - Ludovic Giloteaux
- Department of Microbiology, University of Massachusetts Amherst, MA, USA
| | - Roberto Orellana
- Department of Microbiology, University of Massachusetts Amherst, MA, USA
| | | | | | - Derek R Lovley
- Department of Microbiology, University of Massachusetts Amherst, MA, USA
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