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Xu Y, Teng Y, Wang X, Wang H, Li Y, Ren W, Zhao L, Wei M, Luo Y. Biohydrogen utilization in legume-rhizobium symbiosis reveals a novel mechanism of accelerated tetrachlorobiphenyl transformation. BIORESOURCE TECHNOLOGY 2024; 404:130918. [PMID: 38823562 DOI: 10.1016/j.biortech.2024.130918] [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: 02/03/2024] [Revised: 05/23/2024] [Accepted: 05/30/2024] [Indexed: 06/03/2024]
Abstract
Symbiosis between Glycine max and Bradyrhizobium diazoefficiens were used as a model system to investigate whether biohydrogen utilization promotes the transformation of the tetrachlorobiphenyl PCB77. Both a H2 uptake-positive (Hup+) strain (wild type) and a Hup- strain (a hupL deletion mutant) were inoculated into soybean nodules. Compared with Hup- nodules, Hup+ nodules increased dechlorination significantly by 61.1 % and reduced the accumulation of PCB77 in nodules by 37.7 % (p < 0.05). After exposure to nickel, an enhancer of uptake hydrogenase, dechlorination increased significantly by 2.2-fold, and the accumulation of PCB77 in nodules decreased by 54.4 % (p < 0.05). Furthermore, the tetrachlorobiphenyl transformation in the soybean root nodules was mainly testified to be mediated by nitrate reductase (encoded by the gene NR) for tetrachlorobiphenyl dechlorination and biphenyl-2,3-diol 1,2-dioxygenase (bphC) for biphenyl degradation. This study demonstrates for the first time that biohydrogen utilization has a beneficial effect on tetrachlorobiphenyl biotransformation in a legume-rhizobium symbiosis.
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Affiliation(s)
- Yongfeng Xu
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ying Teng
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Xiaomi Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hongzhe Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanning Li
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenjie Ren
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ling Zhao
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Min Wei
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Yongming Luo
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Zheng T, Hou J, Wu T, Jin H, Dai Y, Xu J, Yang K, Lin D. Ferric Oxide Nanomaterials and Plant-Rhizobacteria Symbionts Cogenerate Iron Plaque for Removing Highly Chlorinated Contaminants in Dryland Soils. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:11063-11073. [PMID: 38869036 DOI: 10.1021/acs.est.4c03133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
Rhizosphere iron plaques derived from Fe-based nanomaterials (NMs) are a promising tool for sustainable agriculture. However, the requirement for flooded conditions to generate iron plaque limits the scope of the NM application. In this study, we achieved in situ Fenton oxidation of a highly chlorinated persistent organic pollutant (2,2',4,5,5'-pentachlorobiphenyl, PCB101) through iron plaque mediated by the interaction between α-Fe2O3 NMs and plant-rhizobacteria symbionts under dryland conditions. Mechanistically, the coexistence of α-Fe2O3 NMs and Pseudomonas chlororaphis JD37 stimulated alfalfa roots to secrete acidic and reductive agents as well as H2O2, which together mediated the rhizosphere Fenton reaction and converted α-Fe2O3 NMs into iron plaque rich in Fe(II)-silicate. Further verifications reproduced the Fenton reaction in vitro using α-Fe2O3 NMs and rhizosphere compounds, confirming the critical role of •OH in the oxidative degradation of PCB101. Significant reductions in PCB101 content by 18.6%, 42.9%, and 23.2% were respectively found in stem, leaf, and soil after a 120-d treatment, proving the effectiveness of this NMs-plant-rhizobacteria technique for simultaneously safe crop production and soil remediation. These findings can help expand the potential applications of nanobio interaction and its mediated iron plaque generation for both agricultural practice and soil remediation.
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Affiliation(s)
- Tianying Zheng
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Jie Hou
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Ting Wu
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Hui Jin
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Yunbu Dai
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Jiang Xu
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Kun Yang
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Daohui Lin
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
- Zhejiang Ecological Civilization Academy, Anji 313300, China
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Wu G, Hou Q, Zhan M, Zhang H, Lv X, Xu Y. Metabolome regulation and restoration mechanism of different varieties of rice (Oryza sativa L.) after lindane stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 913:169839. [PMID: 38184248 DOI: 10.1016/j.scitotenv.2023.169839] [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: 10/07/2023] [Revised: 12/12/2023] [Accepted: 12/30/2023] [Indexed: 01/08/2024]
Abstract
There is a lack of studies on the ability of plants to metabolize chlorinated organic pollutants (COPs) and the dynamic expression changes of metabolic molecules during degradation. In this study, hybrid rice Chunyou 927 (CY) and Zhongzheyou 8 (ZZY), traditional rice subsp. Indica Baohan 1 (BH) and Xiangzaoxian 45 (XZX), and subsp. Japonica Yangjing 687 (YJ) and Longjing 31 (LJ) were stressed by a typical COPs of lindane and then transferred to a lindane-free culture to incubate for 9 days. The cumulative concentrations in the roots of BH, XZX, CY, ZZY, YJ and LJ were 71.46, 65.42, 82.06, 80.11, 47.59 and 56.10 mg·kg-1, respectively. And the degradation ratios on day 9 were 87.89 %, 86.92 %, 94.63 %, 95.49 %, 72.04 % and 82.79 %, respectively. On the 0 day after the release of lindane stress, the accumulated lindane inhibited the normal physiological activities of rice by affecting lipid metabolism in subsp. Indica BH, amino acid metabolism and synthesis and nucleotide metabolism in hybrid CY. Carbohydrate metabolism of subsp. Japonica YJ also was inhibited, but with low accumulation of lindane, YJ regulated amino acid metabolism to resist stress. With the degradation of lindane in rice, the amino acid metabolism of BH and CY, which had high degradation ratios on day 9, was activated to compound biomolecules required for the organism to recover from the damage. Amino acid metabolism and carbohydrate metabolism were disturbed and inhibited mainly in YJ with low degradation ratios. This study provides the difference of the metabolic capacity of the metabolic capacity of different rice varieties to lindane, and changes at the molecular level and metabolic response mechanism of rice during the metabolism of lindane.
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Affiliation(s)
- Guangqi Wu
- College of Environmental Sciences and Engineering, Qingdao University, Qingdao 266071, China
| | - Qian Hou
- College of Environmental Sciences and Engineering, Qingdao University, Qingdao 266071, China
| | - Mengqi Zhan
- College of Environmental Sciences and Engineering, Qingdao University, Qingdao 266071, China
| | - Haoyu Zhang
- College of Environmental Sciences and Engineering, Qingdao University, Qingdao 266071, China
| | - Xiaofei Lv
- Department of Environmental Engineering, China Jiliang University, Hangzhou 310018, China
| | - Yan Xu
- College of Environmental Sciences and Engineering, Qingdao University, Qingdao 266071, China.
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Xu Y, Teng Y, Wang X, Ren W, Zhao L, Luo Y, Christie P, Greening C. Endogenous biohydrogen from a rhizobium-legume association drives microbial biodegradation of polychlorinated biphenyl in contaminated soil. ENVIRONMENT INTERNATIONAL 2023; 176:107962. [PMID: 37196568 DOI: 10.1016/j.envint.2023.107962] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 04/11/2023] [Accepted: 05/04/2023] [Indexed: 05/19/2023]
Abstract
Endogenous hydrogen (H2) is produced through rhizobium-legume associations in terrestrial ecosystems worldwide through dinitrogen fixation. In turn, this gas may alter rhizosphere microbial community structure and modulate biogeochemical cycles. However, very little is understood about the role that this H2 leaking to the rhizosphere plays in shaping the persistent organic pollutants degrading microbes in contaminated soils. Here, we combined DNA-stable isotope probing (DNA-SIP) with metagenomics to explore how endogenous H2 from the symbiotic rhizobium-alfalfa association drives the microbial biodegradation of tetrachlorobiphenyl PCB 77 in a contaminated soil. The results showed that PCB77 biodegradation efficiency increased significantly in soils treated with endogenous H2. Based on metagenomes of 13C-enriched DNA fractions, endogenous H2 selected bacteria harboring PCB degradation genes. Functional gene annotation allowed the reconstruction of several complete pathways for PCB catabolism, with different taxa conducting successive metabolic steps of PCB metabolism. The enrichment through endogenous H2 of hydrogenotrophic Pseudomonas and Magnetospirillum encoding biphenyl oxidation genes drove PCB biodegradation. This study proves that endogenous H2 is a significant energy source for active PCB-degrading communities and suggests that elevated H2 can influence the microbial ecology and biogeochemistry of the legume rhizosphere.
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Affiliation(s)
- Yongfeng Xu
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Ying Teng
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
| | - Xiaomi Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Wenjie Ren
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Ling Zhao
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Yongming Luo
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Peter Christie
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
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Rolli E, Vergani L, Ghitti E, Patania G, Mapelli F, Borin S. 'Cry-for-help' in contaminated soil: a dialogue among plants and soil microbiome to survive in hostile conditions. Environ Microbiol 2021; 23:5690-5703. [PMID: 34139059 PMCID: PMC8596516 DOI: 10.1111/1462-2920.15647] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/25/2021] [Accepted: 06/16/2021] [Indexed: 12/20/2022]
Abstract
An open question in environmental ecology regards the mechanisms triggered by root chemistry to drive the assembly and functionality of a beneficial microbiome to rapidly adapt to stress conditions. This phenomenon, originally described in plant defence against pathogens and predators, is encompassed in the ‘cry‐for‐help’ hypothesis. Evidence suggests that this mechanism may be part of the adaptation strategy to ensure the holobiont fitness in polluted environments. Polychlorinated biphenyls (PCBs) were considered as model pollutants due to their toxicity, recalcitrance and poor phyto‐extraction potential, which lead to a plethora of phytotoxic effects and rise environmental safety concerns. Plants have inefficient detoxification processes to catabolize PCBs, even leading to by‐products with a higher toxicity. We propose that the ‘cry‐for‐help’ mechanism could drive the exudation‐mediated recruitment and sustainment of the microbial services for PCBs removal, exerted by an array of anaerobic and aerobic microbial degrading populations working in a complex metabolic network. Through this synergistic interaction, the holobiont copes with the soil contamination, releasing the plant from the pollutant stress by the ecological services provided by the boosted metabolism of PCBs microbial degraders. Improving knowledge of root chemistry under PCBs stress is, therefore, advocated to design rhizoremediation strategies based on plant microbiome engineering.
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Affiliation(s)
- Eleonora Rolli
- Department of Food, Environmental and Nutritional Sciences, DeFENS, University of Milan, Via Celoria 2, Milan, 20133, Italy
| | - Lorenzo Vergani
- Department of Food, Environmental and Nutritional Sciences, DeFENS, University of Milan, Via Celoria 2, Milan, 20133, Italy
| | - Elisa Ghitti
- Department of Food, Environmental and Nutritional Sciences, DeFENS, University of Milan, Via Celoria 2, Milan, 20133, Italy
| | - Giovanni Patania
- Department of Food, Environmental and Nutritional Sciences, DeFENS, University of Milan, Via Celoria 2, Milan, 20133, Italy
| | - Francesca Mapelli
- Department of Food, Environmental and Nutritional Sciences, DeFENS, University of Milan, Via Celoria 2, Milan, 20133, Italy
| | - Sara Borin
- Department of Food, Environmental and Nutritional Sciences, DeFENS, University of Milan, Via Celoria 2, Milan, 20133, Italy
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Hao D, Wang H, Niu L. Activation of six lipocalins genes' transcription under PCB18 stress in OsTIL-silenced Oryza sativa L. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 204:111063. [PMID: 32791358 DOI: 10.1016/j.ecoenv.2020.111063] [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: 01/06/2020] [Revised: 07/12/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
The lipocalins genes have been assigned for involving in the responses of organisms to various stress factors. The function of lipocalins under PCB18 stress was addressed by pathway complementation in the Oryza sativa L. OsTIL-silenced mutant. The growth of wild type (WT) and OsTIL-silenced mutant (MT) callus were suppressed by PCB18, and MT varieties were inhibited more seriously than WT varieties. Meanwhile, only WT varieties showed "Hormesis" effect. Compared with WT (3 day > 90.0%, 6 day ≤45.5%), MT varieties kept high removing efficiency by HPLC analysis. Varied gene transcription after OsTIL silencing was demonstrated between two varieties, especially obvious under PCB stress. Silenced OsTIL induced more protective gene transcriptions by qPCR analysis, OsVDE at 3 day, OsCHL, OsZEP1, OsZEP2 and OsUN at 6 day and OsZEP2 at 9 day. PCB18 stress further irritated these genes transcription in MT varieties. The defense stagy in WT varieties was that the transcriptions of lipocalins were inhibited to reduce PCB18 accumulation and toxicity. OsTIL could effectively limit PCB18 accumulation and toxicity. After TIL lacking, OsCHL, OsZEP1, OsZEP2 and OsUN in mutant were strongly evoked to against PCB stress. Remarkably, OsUN and OsZEP2 gene expressions were responded to PCB18 stress in both two varieties.
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Affiliation(s)
- Dehou Hao
- University of Science and Technology Beijing School of Chemistry and Biological Engineering, Department of Biological Science and Engineering, 30 Xueyuan Road, Haidian District, Beijing, 100083 China
| | - Haiou Wang
- University of Science and Technology Beijing School of Chemistry and Biological Engineering, Department of Biological Science and Engineering, 30 Xueyuan Road, Haidian District, Beijing, 100083 China.
| | - Lin Niu
- University of Science and Technology Beijing School of Chemistry and Biological Engineering, 30 Xueyuan Road, Haidian District, Beijing, 100083 China
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Meglouli H, Fontaine J, Verdin A, Magnin-Robert M, Tisserant B, Hijri M, Sahraoui ALH. Aided Phytoremediation to Clean Up Dioxins/Furans-Aged Contaminated Soil: correlation between microbial communities and pollutant dissipation. Microorganisms 2019; 7:E523. [PMID: 31684182 PMCID: PMC6920798 DOI: 10.3390/microorganisms7110523] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/24/2019] [Accepted: 10/31/2019] [Indexed: 11/16/2022] Open
Abstract
To restore and clean up polluted soils, aided phytoremediation was found to be an effective, eco-friendly, and feasible approach in the case of many organic pollutants. However, little is known about its potential efficiency regarding polychlorinated dibenzo-p-dioxins and furans-contaminated soils. Thus, phytoremediation of aged dioxins/furans-contaminated soil was carried out through microcosm experiments vegetated with alfalfa combined with different amendments: an arbuscular mycorrhizal fungal inoculum (Funneliformis mosseae), a biosurfactant (rhamnolipids), a dioxins/furans degrading-bacterium (Sphingomonas wittichii RW1), and native microbiota. The total dioxins/furans dissipation was estimated to 23%, which corresponds to 48 ng.kg-1 of soil, after six months of culture in the vegetated soil combined with the four amendments compared to the non-vegetated soil. Our findings showed that the dioxins/furans dissipation resulted from the stimulation of soil microbial enzyme activities (fluorescein diacetate hydrolase and dehydrogenase) and the increase of bacterial abundance, richness, and diversity, as well as fungal diversity. Amplicon sequencing using Illumina MiSeq analysis led to identification of several bacterial (Bacillaceae, Sphingomonadaceae) and fungal (Chaetomium) groups known to be involved in dioxins/furans degradation. Furthermore, concomitant cytotoxicity and dioxins/furans concentration decreases were pointed out in the phytoremediated soil. The current study demonstrated the usefulness of combining different types of amendments to improve phytoremediation efficacy of aged dioxins/furans-contaminated soils.
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Affiliation(s)
- Hacène Meglouli
- Université du Littoral Côte d'Opale, UCEIV-EA 4492, SFR Condorcet FR CNRS 3417, CS 80699, F-62228 Calais cedex, France.
| | - Joël Fontaine
- Université du Littoral Côte d'Opale, UCEIV-EA 4492, SFR Condorcet FR CNRS 3417, CS 80699, F-62228 Calais cedex, France.
| | - Anthony Verdin
- Université du Littoral Côte d'Opale, UCEIV-EA 4492, SFR Condorcet FR CNRS 3417, CS 80699, F-62228 Calais cedex, France.
| | - Maryline Magnin-Robert
- Université du Littoral Côte d'Opale, UCEIV-EA 4492, SFR Condorcet FR CNRS 3417, CS 80699, F-62228 Calais cedex, France.
| | - Benoit Tisserant
- Université du Littoral Côte d'Opale, UCEIV-EA 4492, SFR Condorcet FR CNRS 3417, CS 80699, F-62228 Calais cedex, France.
| | - Mohamed Hijri
- Institut de Recherche en Biologie Végétale, Université de Montréal and Jardin botanique de Montréal, 4101 Rue Sherbrooke Est, Montréal, QC H1X 2B2, Canada.
- AgroBioSciences, Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, Ben Guerir, 43150 Morocco.
| | - Anissa Lounès-Hadj Sahraoui
- Université du Littoral Côte d'Opale, UCEIV-EA 4492, SFR Condorcet FR CNRS 3417, CS 80699, F-62228 Calais cedex, France.
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Wang X, Teng Y, Tu C, Luo Y, Greening C, Zhang N, Dai S, Ren W, Zhao L, Li Z. Coupling between Nitrogen Fixation and Tetrachlorobiphenyl Dechlorination in a Rhizobium-Legume Symbiosis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:2217-2224. [PMID: 29363956 DOI: 10.1021/acs.est.7b05667] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Legume-rhizobium symbioses have the potential to remediate soils contaminated with chlorinated organic compounds. Here, the model symbiosis between Medicago sativa and Sinorhizobium meliloti was used to explore the relationships between symbiotic nitrogen fixation and transformation of tetrachlorobiphenyl PCB 77 within this association. 45-day-old seedlings in vermiculite were pretreated with 5 mg L-1 PCB 77 for 5 days. In PCB-supplemented nodules, addition of the nitrogenase enhancer molybdate significantly stimulated dechlorination by 7.2-fold and reduced tissue accumulation of PCB 77 (roots by 96% and nodules by 93%). Conversely, dechlorination decreased in plants exposed to a nitrogenase inhibitor (nitrate) or harboring nitrogenase-deficient symbionts (nifA mutant) by 29% and 72%, respectively. A range of dechlorinated products (biphenyl, methylbiphenyls, hydroxylbiphenyls, and trichlorobiphenyl derivatives) were detected within nodules and roots under nitrogen-fixing conditions. Levels of nitrogenase-derived hydrogen and leghemoglobin expression correlated positively with nodular dechlorination rates, suggesting a more reducing environment promotes PCB dechlorination. Our findings demonstrate for the first time that symbiotic nitrogen fixation acts as a driving force for tetrachlorobiphenyl dechlorination. In turn, this opens new possibilities for using rhizobia to enhance phytoremediation of halogenated organic compounds.
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Affiliation(s)
- Xiaomi Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences, Nanjing 210008, P.R. China
- University of Chinese Academy of Sciences , Beijing 100049, P.R. China
| | - Ying Teng
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences, Nanjing 210008, P.R. China
| | - Chen Tu
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research , Chinese Academy of Sciences, Yantai 264003, P.R. China
| | - Yongming Luo
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences, Nanjing 210008, P.R. China
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research , Chinese Academy of Sciences, Yantai 264003, P.R. China
| | - Chris Greening
- School of Biological Sciences, Monash University , Clayton, Victoria 3800, Australia
| | - Ning Zhang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences, Nanjing 210008, P.R. China
| | - Shixiang Dai
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences, Nanjing 210008, P.R. China
- University of Chinese Academy of Sciences , Beijing 100049, P.R. China
| | - Wenjie Ren
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences, Nanjing 210008, P.R. China
| | - Ling Zhao
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences, Nanjing 210008, P.R. China
| | - Zhengao Li
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences, Nanjing 210008, P.R. China
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