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Ge M, Zhou S, Li D, Song D, Yang S, Xu M. Reduction of selenite to selenium nanoparticles by highly selenite-tolerant bacteria isolated from seleniferous soil. JOURNAL OF HAZARDOUS MATERIALS 2024; 472:134491. [PMID: 38703686 DOI: 10.1016/j.jhazmat.2024.134491] [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: 02/07/2024] [Revised: 04/26/2024] [Accepted: 04/29/2024] [Indexed: 05/06/2024]
Abstract
The microbial reduction of selenite to elemental selenium nanoparticles (SeNPs) is thought to be an effective detoxification process of selenite for many bacteria. In this study, Metasolibacillus sp. ES129 and Oceanobacillus sp. ES111 with high selenite reduction efficiency or tolerance were selected for systematic and comparative studies on their performance in selenite removal and valuable SeNPs recovery. The kinetic monitoring of selenite reduction showed that the highest transformation efficiency of selenite to SeNPs was achieved at a concentration of 4.24 mM for ES129 and 4.88 mM for ES111. Ultramicroscopic analysis suggested that the SeNPs produced by ES111 and ES129 had been formed in cytoplasm and subsequently released to extracellular space through cell lysis process. Furthermore, the transcriptome analysis indicated that the expression of genes involved in bacillithiol biosynthesis, selenocompound metabolism and proline metabolism were significantly up-regulated during selenite reduction, suggesting that the transformation of selenite to Se0 may involve multiple pathways. Besides, the up-regulation of genes associated with nucleotide excision repair and antioxidation-related enzymes may enhance the tolerance of bacteria to selenite. Generally, the exploration of selenite reduction and tolerance mechanisms of the highly selenite-tolerant bacteria is of great significance for the effective utilization of microorganisms for environmental remediation.
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Affiliation(s)
- Meng Ge
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China; Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou 510070, China
| | - Shaofeng Zhou
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China; Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou 510070, China
| | - Daobo Li
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China; Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou 510070, China
| | - Da Song
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China; Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou 510070, China
| | - Shan Yang
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China; Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou 510070, China
| | - Meiying Xu
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China; Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou 510070, China.
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2
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Li K, Zhu Y, Zhang S, Xu Q, Guo Y. Nitrate reductase involves in selenite reduction in Rahnella aquatilis HX2 and the characterization and anticancer activity of the biogenic selenium nanoparticles. J Trace Elem Med Biol 2024; 83:127387. [PMID: 38237425 DOI: 10.1016/j.jtemb.2024.127387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/18/2023] [Accepted: 01/08/2024] [Indexed: 03/18/2024]
Abstract
BACKGROUND Biogenic selenium nanoparticles (SeNPs) show numerous advantages including their high stability, low toxicity, and high bioactivity. While metabolism of SeNPs remains not well studied and need more investigation to reveal the process. PURPOSE The objective of the study was to investigate the relationship between nitrate reductase and selenite reduction in Rahnella aquatilis HX2, characterize the properties of HX2 produced SeNPs, and explore their potential applications, particularly their anticancer activity. PROCEDURES Selenium species were measured by high-performance liquid chromatography coupled to inductively coupled plasma - Mass spectrometry (HPLC-ICP-MS). Transcription level of nitrate reductase was determined by Real-time quantitative PCR. Morphology, particle size, crystal structure and surface chemistry of SeNPs were determined by electron microscopy, dynamic light scattering method, Raman scattering, X-ray photoelectron spectroscopy, respectively. Anti cancer cell activity was measured by CCK-8 assay. MAIN FINDINGS SeNP production in R. aquatilis HX2 was correlated with the cell growth. The products of selenite reduction in HX2 detected by HPLC-ICP-MS included SeNPs, selenocysteine (SeCys), Se-Methylselenocysteine (MeSeCys), and 7 unknown compounds. Nitrate addition experiments suggested the involvement of nitrate reductase in selenite reduction in HX2. Both the cellular membrane and cytoplasm of HX2 exhibited selenite-reducing ability, indicating that membrane-associated nitrate reductase was not the sole selenite reductase in HX2. Characterization of the biogenic SeNPs revealed a spherical morphology and amorphous structure of them. Surface chemistry analysis implicated the binding of extracellular polymeric substances to the biogenic SeNPs, and the presence of Se0, Se2-, and electron-rich Se atoms on the surface of SeNPs. Finally, the IC50 values of the biogenic SeNPs were 36.49 μM for HepG2 and 3.70 μM for HeLa cells. CONCLUSIONS The study first revealed that the nitrate reductase is involving in selenite reduction in R. aquatilis HX2. The biogenic SeNPs coordinated with organic substances in the surface. And SeNPs produced by R. aquatilis HX2 showed excellent anticancer activities on HepG2 and HeLa cells.
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Affiliation(s)
- Kui Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Yanyun Zhu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China; Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences; Key Laboratory for Crop and Animal Integrated Farming of Ministry of Agriculture and Rural Affairs, Nanjing 210014, China
| | - Sasa Zhang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Qiaolin Xu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Yanbin Guo
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China.
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3
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Gao H, Ji Y, Chen W. Selenite resistance and biotransformation to SeNPs in Sinorhizobium meliloti 1021 and the synthetic promotion on alfalfa growth. Microbiol Res 2024; 280:127568. [PMID: 38118306 DOI: 10.1016/j.micres.2023.127568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/02/2023] [Accepted: 12/04/2023] [Indexed: 12/22/2023]
Abstract
Toxic selenite, commonly found in soil and water, can be transformed by microorganisms into selenium nanoparticles (SeNPs) as part of a detoxification process. In this study, a comprehensive investigation was conducted on the resistance and biotransformation of selenite in Sinorhizobium meliloti 1021 and the synergistic impact of SeNPs and the strain on alfalfa growth promotion was explored. Strain 1021 reduced 46% of 5 mM selenite into SeNPs within 72 h. The SeNPs, composed of proteins, lipids and polysaccharides, were primarily located outside rhizobial cells and had a tendency to aggregate. Under selenite stress, many genes participated in multidrug efflux, sulfur metabolism and redox processes were significantly upregulated. Of them, four genes, namely gmc, yedE, dsh3 and mfs, were firstly identified in strain 1021 that played crucial roles in selenite biotransformation and resistance. Biotoxic evaluations showed that selenite had toxic effects on roots and seedlings of alfalfa, while SeNPs exhibited antioxidant properties, promoted growth, and enhanced plant's tolerance to salt stress. Overall, our research provides novel insights into selenite biotransformation and resistance mechanisms in rhizobium and highlights the potential of SeNPs-rhizobium complex as biofertilizer to promote legume growth and salt tolerance.
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Affiliation(s)
- Huali Gao
- College of Biological Sciences and Rhizobium Research Center, China Agricultural University, Beijing 100193, China
| | - Yingrui Ji
- College of Biological Sciences and Rhizobium Research Center, China Agricultural University, Beijing 100193, China
| | - Wenfeng Chen
- College of Biological Sciences and Rhizobium Research Center, China Agricultural University, Beijing 100193, China.
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4
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Jing J, Sun L, Chen Z, Guo X, Qu Y. Simultaneous selenite reduction and nitrogen removal using Paracoccus sp.: Reactor performance, microbial community, and mechanism. ENVIRONMENTAL RESEARCH 2024; 240:117564. [PMID: 37918763 DOI: 10.1016/j.envres.2023.117564] [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: 10/03/2023] [Revised: 10/26/2023] [Accepted: 10/30/2023] [Indexed: 11/04/2023]
Abstract
Selenium-containing wastewater has a high concentration of nitrogen compounds (ammonia nitrogen [NH4+-N]), leading to water pollution. Thus, the simultaneous reduction of selenium and removal of nitrogen compounds during wastewater treatment has become the top priority. However, the exogenous bacteria that can simultaneously reduce selenite and remove ammonia nitrogen and colonize in the wastewater treatment systems have not been reported. Additionally, the effects and the underlying mechanism of biofortification on the reduction and removal efficiency of the microorganisms remain unclear. In this study, we investigated the simultaneous selenite reduction and nitrogen removal efficiency of Paracoccus sp. (strain SSJ) isolated from selenium-contaminated soil and explored biofortification effects on the composition and structure of the microbial community. Using sequencing biofilm batch reactors (SBBRs), the structural and functional characteristics of the microbial community were systematically compared between the control (group A) and biofortified (group B) groups. Strain SSJ could simultaneously reduce 63.28% of selenite and remove 93.05% of NH4+-N within 24 h. Moreover, no accumulation of nitrate nitrogen (NO3--N) and nitrite nitrogen (NO2--N) was observed in the reaction process. The performance and stability of the SBBRs enhanced by strain SSJ were greatly improved. Illumina sequencing results showed that strain SSJ was surprisingly colonized, and Paracoccus was the predominant genus in group B (relative abundance: 13.93%). Moreover, PICRUSt2 analysis results suggested that the microbial community in group B demonstrated increased rates of ammonia nitrogen removal through ammonia assimilation and selenite reduction through sulfur metabolism and glutathione-mediated selenite reduction pathway. In summary, our findings shed light on the mechanism for simultaneous selenite reduction and nitrogen removal by biofortification and provide novel microbial resources for the treatment of selenite-containing wastewater.
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Affiliation(s)
- Jiawei Jing
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Lu Sun
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Zhuo Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Xinyu Guo
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Yuanyuan Qu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) and Dalian POCT Laboratory, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
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Yadav P, Pandey S, Dubey SK. Selenite bioreduction with concomitant green synthesis of selenium nanoparticles by a selenite resistant EPS and siderophore producing terrestrial bacterium. Biometals 2023; 36:1027-1045. [PMID: 37119424 DOI: 10.1007/s10534-023-00503-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 04/11/2023] [Indexed: 05/01/2023]
Abstract
Environmental bacterial isolates play a very important role in bioremediation of metals and toxic metalloids. A bacterial strain with high selenite (SeO32-) tolerance and reducing capability was isolated from electronic waste dump site in Banaras Hindu University, Varanasi, India. Based on 16 S rRNA sequencing and BLAST search, this bacterial isolate was identified as Bacillus paramycoides and designated as strain MF-14. It tolerated Sodium selenite up to 110 mM when grown aerobically in LB broth and reduced selenite into elemental selenium (Se0) significantly within 24 h with concomitant biosynthesis of selenium nanoparticles as clearly revealed by brick red precipitate and specific surface plasmon resonance peak at 210 nm using UV-Visible spectrophotometer. Scanning electron microscopy (SEM) analysis of this bacterial strain exposed to 1mM and 5 mM selenite also demonstrated morphological alterations as cell enlargement due to accumulation and bioprecipitation of elemental selenium (Se0). The FTIR analysis clearly demonstrated that functional groups present on the surface of biogenic selenium nanoparticles (SeNPs) play a significant role in the stabilization and capping of SeNPs. Furthermore, these SeNPs were characterized using spectroscopic analysis involving Dynamic light scattering, zeta potential, XPS, FTIR, XRD and Raman spectroscopy which clearly revealed particle size 10-700 nm, amorphous nature, stability as well as it's oxidation state. The biochemical studies have demonstrated that membrane bound reductase enzyme may be responsible for significant reduction of selenite into elemental selenium. Therefore, we may employ Bacillus paramycoides strain MF-14 successfully for bioremediation of selenite contaminated environmental sites with concomitant green synthesis of SeNPs.
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Affiliation(s)
- Pooja Yadav
- G. E. Fogg Laboratory of Algal Biology, CAS in Botany, Banaras Hindu University, Varanasi, 221005, U.P, India
| | - Shraddha Pandey
- G. E. Fogg Laboratory of Algal Biology, CAS in Botany, Banaras Hindu University, Varanasi, 221005, U.P, India
| | - Santosh Kumar Dubey
- G. E. Fogg Laboratory of Algal Biology, CAS in Botany, Banaras Hindu University, Varanasi, 221005, U.P, India.
- Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India.
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Xu R, Kolton M, Tao W, Sun X, Su P, Huang D, Zhang M, Yang Z, Guo Z, Gao H, Wang Q, Li B, Chen C, Sun W. Anaerobic selenite-reducing bacteria and their metabolic potentials in Se-rich sediment revealed by the combination of DNA-stable isotope probing, metagenomic binning, and metatranscriptomics. JOURNAL OF HAZARDOUS MATERIALS 2023; 457:131834. [PMID: 37327607 DOI: 10.1016/j.jhazmat.2023.131834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 06/04/2023] [Accepted: 06/09/2023] [Indexed: 06/18/2023]
Abstract
Microorganisms play a critical role in the biogeochemical cycling of selenium (Se) in aquatic environments, particularly in reducing the toxicity and bioavailability of selenite (Se(IV)). This study aimed to identify putative Se(IV)-reducing bacteria (SeIVRB) and investigate the genetic mechanisms underlying Se(IV) reduction in anoxic Se-rich sediment. Initial microcosm incubation confirmed that Se(IV) reduction was driven by heterotrophic microorganisms. DNA stable-isotope probing (DNA-SIP) analysis identified Pseudomonas, Geobacter, Comamonas, and Anaeromyxobacter as putative SeIVRB. High-quality metagenome-assembled genomes (MAGs) affiliated with these four putative SeIVRB were retrieved. Annotation of functional gene indicated that these MAGs contained putative Se(IV)-reducing genes such as DMSO reductase family, fumarate and sulfite reductases. Metatranscriptomic analysis of active Se(IV)-reducing cultures revealed significantly higher transcriptional levels of genes associated with DMSO reductase (serA/PHGDH), fumarate reductase (sdhCD/frdCD), and sulfite reductase (cysDIH) compared to those in cultures not amended with Se(IV), suggesting that these genes played important roles in Se(IV) reduction. The current study expands our knowledge of the genetic mechanisms involved in less-understood anaerobic Se(IV) bio-reduction. Additinally, the complementary abilities of DNA-SIP, metagenomics, and metatranscriptomics analyses are demonstrated in elucidating the microbial mechanisms of biogeochemical processes in anoxic sediment.
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Affiliation(s)
- Rui Xu
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, PR China; National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, PR China
| | - Max Kolton
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, PR China
| | - Wan Tao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, PR China
| | - Xiaoxu Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, PR China
| | - Pingzhou Su
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, PR China
| | - Duanyi Huang
- College of Environmental Science and Engineering, Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), Hunan University, Changsha 410082, PR China
| | - Miaomiao Zhang
- Key Laboratory of Water Quality and Conservation in the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China
| | - Zhaohui Yang
- College of Environmental Science and Engineering, Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), Hunan University, Changsha 410082, PR China
| | - Zhaohui Guo
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, PR China
| | - Hanbing Gao
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, PR China
| | - Qi Wang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, PR China
| | - Baoqin Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, PR China
| | - Chengyu Chen
- College of Natural Resources and Environment, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, South China Agricultural University, Guangzhou 510642, China
| | - Weimin Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, PR China; School of Environment, Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control (Ministry of Education), Henan Normal University, Xinxiang 453007, PR China.
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7
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Ullah H, Lun L, Rashid A, Zada N, Chen B, Shahab A, Li P, Ali MU, Lin S, Wong MH. A critical analysis of sources, pollution, and remediation of selenium, an emerging contaminant. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:1359-1389. [PMID: 35972610 PMCID: PMC9379879 DOI: 10.1007/s10653-022-01354-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 07/09/2022] [Indexed: 06/10/2023]
Abstract
Selenium (Se) is an essential metalloid and is categorized as emerging anthropogenic contaminant released to the environment. The rise of Se release into the environment has raised concern about its bioaccumulation, toxicity, and potential to cause serious damages to aquatic and terrestrial ecosystem. Therefore, it is extremely important to monitor Se level in environment on a regular basis. Understanding Se release, anthropogenic sources, and environmental behavior is critical for developing an effective Se containment strategy. The ongoing efforts of Se remediation have mostly emphasized monitoring and remediation as an independent topics of research. However, our paper has integrated both by explaining the attributes of monitoring on effective scale followed by a candid review of widespread technological options available with specific focus on Se removal from environmental media. Another novel approach demonstrated in the article is the presentation of an overwhelming evidence of limitations that various researchers are confronted with to overcome achieving effective remediation. Furthermore, we followed a holistic approach to discuss ways to remediate Se for cleaner environment especially related to introducing weak magnetic field for ZVI reactivity enhancement. We linked this phenomenal process to electrokinetics and presented convincing facts in support of Se remediation, which has led to emerge 'membrane technology', as another viable option for remediation. Hence, an interesting, innovative and future oriented review is presented, which will undoubtedly seek attention from global researchers.
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Affiliation(s)
- Habib Ullah
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058 Zhejiang China
- Zhejiang Provincial Key Laboratory of Organic Pollutant Process and Control, Zhejiang University, Hangzhou, 310058 Zhejiang China
| | - Lu Lun
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510655 China
| | - Audil Rashid
- Faculty of Sciences, Department of Botany, University of Gujrat, Gujrat, 50700 Pakistan
| | - Noor Zada
- Department of Chemistry, Government Post Graduate College, Lower Dir, Timergara, 18300 Pakistan
| | - Baoliang Chen
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058 Zhejiang China
- Zhejiang Provincial Key Laboratory of Organic Pollutant Process and Control, Zhejiang University, Hangzhou, 310058 Zhejiang China
| | - Asfandyar Shahab
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China
| | - Ping Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Science, Guiyang, 550081 China
- CAS Center for Excellence in Quaternary Science and Global Change in XI’an, Xi’an, 710061 China
| | - Muhammad Ubaid Ali
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Science, Guiyang, 550081 China
- CAS Center for Excellence in Quaternary Science and Global Change in XI’an, Xi’an, 710061 China
| | - Siyi Lin
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, 999077 China
| | - Ming Hung Wong
- Consortium On Health, Environment, Education, and Research (CHEER), Department of Science and Environmental Studies, The Education University of Hong Kong, Hong Kong, China
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Jia H, Huang S, Cheng S, Zhang X, Chen X, Zhang Y, Wang J, Wu L. Novel mechanisms of selenite reduction in Bacillus subtilis 168:Confirmation of multiple-pathway mediated remediation based on transcriptome analysis. JOURNAL OF HAZARDOUS MATERIALS 2022; 433:128834. [PMID: 35398797 DOI: 10.1016/j.jhazmat.2022.128834] [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: 01/18/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 06/14/2023]
Abstract
Selenite biotransformation by microorganisms is an effective detoxification and assimilation process. Bacillus subtilis is a probiotic bacterium that can reduce Se(IV) to SeNPs under aerobic conditions. However, current knowledge on the molecular mechanisms of selenite reduction by B. subtilis remains limited. Here, the reduction of Se(IV) by probiotic bacterium Bacillus subtilis 168 was systematically analysed, and the molecular mechanisms of selenium nanoparticle (SeNPs) formation were characterised in detail. B. subtilis 168 reduced 5.0 mM selenite by nearly 40% in 24 h, and the produced SeNPs were spherical and localised intracellularly or extracellularly. FTIR (Fourier transform infrared) spectroscopy suggested the presence of proteins, lipids, and carbohydrates on the surface of the isolated SeNPs. Transcriptome data analysis revealed that the expression of genes associated with the proline metabolism, glutamate metabolism, and sulfite metabolism pathways was significantly up-regulated. Gene mutation and complementation revealed the ability of PutC, GabD, and CysJI to reduce selenite in vivo. In vitro experiments demonstrated that PutC, GabD, and CysJI could catalyse the reduction of Se(IV) under optimal conditions using NADPH as a cofactor. To the best of our knowledge, our study is the first to demonstrate the involvement of PutC and GabD in selenite reduction. Particularly, our findings demonstrated that the reduction of Se(IV) was mediated by multiple pathways both in vivo and in vitro. Our findings thus provide novel insights into the molecular mechanisms of Se(VI) reduction in aerobic bacteria.
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Affiliation(s)
- Huiling Jia
- The Center for Ion Beam Bioengineering & Green Agriculture, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China; School of Life Science, University of Science and Technology of China, Hefei 230027 Anhui, China
| | - Shengwei Huang
- Institute of Biomedical and Health Science, School of Life and Health Science, Anhui Science and Technology University, Fengyang, Anhui, 233100, PR China.
| | - Shuo Cheng
- The Center for Ion Beam Bioengineering & Green Agriculture, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China; School of Life Science, University of Science and Technology of China, Hefei 230027 Anhui, China
| | - Xiwen Zhang
- The Center for Ion Beam Bioengineering & Green Agriculture, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China; School of Life Science, University of Science and Technology of China, Hefei 230027 Anhui, China
| | - Xue Chen
- The Center for Ion Beam Bioengineering & Green Agriculture, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China; School of Life Science, University of Science and Technology of China, Hefei 230027 Anhui, China
| | - Yisen Zhang
- The Center for Ion Beam Bioengineering & Green Agriculture, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China
| | - Jun Wang
- The Center for Ion Beam Bioengineering & Green Agriculture, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China
| | - Lifang Wu
- The Center for Ion Beam Bioengineering & Green Agriculture, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, Anhui, China; School of Life Science, University of Science and Technology of China, Hefei 230027 Anhui, China; Zhongke Taihe Experimental Station, Taihe 236626, Anhui, China.
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9
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Gong Y, Wu Y, Khan A, Song P, Wang Z, Ni H, Ji J, Salama ES, Liu P, Li X. Improving selenium accumulation in broilers using Escherichia coli Nissle 1917 with surface-displayed selenite reductase SerV01. Food Funct 2022; 13:4537-4550. [PMID: 35348561 DOI: 10.1039/d2fo00206j] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Selenium levels have a critical impact on livestock and poultry, and selenium nanoparticles (SeNPs) have shown significant efficiency in supplementation. This study identified a high-efficiency selenite reductase, SerV01, in Staphylococcus aureus LZ-01, which can convert Se2O32- to SeNPs. Subsequently, SerV01 was introduced into the intestines of the broilers using the surface display-engineered E. coli Nissle 1917 (EcN). The results showed that the engineered bacteria (EcN-IS) significantly increased the selenium content by 0.87 mg kg-1, 0.52 mg kg-1, and 6.10 mg L-1 in the liver, breast muscle, and serum, respectively. With SeNPs + EcN-IS treatment, glutathione peroxidase and thioredoxin reductase levels reached 0.7536 ± 0.03176 U μL-1 protein and 2.463 ± 0.1685 U μL-1 protein, respectively. With the modified probiotics, the proportion of beneficial intestinal flora increased, with Lactobacillus and Propionibacterium accounting for 75.85% and 0.19%. This technology provides a novel idea to facilitate the exploitation of selenium in broiler diets and improve antioxidant capability.
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Affiliation(s)
- Yuxin Gong
- Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Tianshuinanlu #222, Lanzhou 730000, Gansu, China.
| | - Ying Wu
- Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Tianshuinanlu #222, Lanzhou 730000, Gansu, China.
| | - Aman Khan
- Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Tianshuinanlu #222, Lanzhou 730000, Gansu, China.
| | - Peizhi Song
- Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Tianshuinanlu #222, Lanzhou 730000, Gansu, China.
| | - Zhenfei Wang
- Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Tianshuinanlu #222, Lanzhou 730000, Gansu, China.
| | - Hongyuhang Ni
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Jing Ji
- Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Tianshuinanlu #222, Lanzhou 730000, Gansu, China.
| | - El-Sayed Salama
- Department of Occupational and Environmental Health, School of Public Health, Lanzhou University, Lanzhou, 730000, Gansu, PR China
| | - Pu Liu
- Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Tianshuinanlu #222, Lanzhou 730000, Gansu, China.
| | - Xiangkai Li
- Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Tianshuinanlu #222, Lanzhou 730000, Gansu, China.
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10
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Nancharaiah YV, Sarvajith M. Aerobic granular sludge for efficient biotransformation of chalcogen Se IV and Te IV oxyanions: Biological nutrient removal and biogenesis of Se 0 and Te 0 nanostructures. JOURNAL OF HAZARDOUS MATERIALS 2022; 422:126833. [PMID: 34399215 DOI: 10.1016/j.jhazmat.2021.126833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/29/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
Simultaneous removal of selenite (SeIV), tellurite (TeIV) and nutrients by aerobic granular sludge (AGS) was investigated. A sequencing batch reactor (SBR) was operated with increasing SeIV and TeIV (up to 500 µM each) for 205 days to evaluate metalloid oxyanion and nutrient removal. AGS efficiently removed SeIV and TeIV by readily converting them to biomass associated forms. The total Se and Te removal efficiencies were higher at 98% and 99%, respectively. Formation of biomass-associated Se0 and Te0 was confirmed by XRD, Raman spectroscopy and SEM-EDX. Feeding of SeIV and TeIV elicited inhibitory action on ammonium removal initially, nonetheless removal performance was recovered during the subsequent cycles. Ammonium, total nitrogen and phosphorus removals were stabilized at 85%, 80% and 75%, respectively, at 500 µM of SeIV and TeIV. Sequencing of 16S rRNA gene confirmed enrichment of known SeIV and TeIV reducing bacteria in the granules. qPCR and removal kinetics supported ammonia removal via nitritation-denitritation. This work demonstrates functional capabilities of AGS for effectively removing toxic SeIV and TeIV oxyanions apart from performing simultaneous COD, nitrogen and phosphorus removal. Efficient biological nutrient removal in the presence of toxic SeIV and TeIV concentrations, suggests robustness of AGS and its resilience to toxic contaminants.
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Affiliation(s)
- Y V Nancharaiah
- Biofouling and Biofilm Processes, Water & Steam Chemistry Division, Chemistry Group, Bhabha Atomic Research Centre, Kalpakkam 603102, India; Homi Bhabha National Institute, BARC Training School Complex, Anushakti Nagar, Trombay, Mumbai 400 094, India.
| | - M Sarvajith
- Biofouling and Biofilm Processes, Water & Steam Chemistry Division, Chemistry Group, Bhabha Atomic Research Centre, Kalpakkam 603102, India; Homi Bhabha National Institute, BARC Training School Complex, Anushakti Nagar, Trombay, Mumbai 400 094, India
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11
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Shi LD, Lv PL, McIlroy SJ, Wang Z, Dong XL, Kouris A, Lai CY, Tyson GW, Strous M, Zhao HP. Methane-dependent selenate reduction by a bacterial consortium. THE ISME JOURNAL 2021; 15:3683-3692. [PMID: 34183781 PMCID: PMC8630058 DOI: 10.1038/s41396-021-01044-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/08/2021] [Accepted: 06/15/2021] [Indexed: 02/06/2023]
Abstract
Methanotrophic microorganisms play a critical role in controlling the flux of methane from natural sediments into the atmosphere. Methanotrophs have been shown to couple the oxidation of methane to the reduction of diverse electron acceptors (e.g., oxygen, sulfate, nitrate, and metal oxides), either independently or in consortia with other microbial partners. Although several studies have reported the phenomenon of methane oxidation linked to selenate reduction, neither the microorganisms involved nor the underlying trophic interaction has been clearly identified. Here, we provide the first detailed evidence for interspecies electron transfer between bacterial populations in a bioreactor community where the reduction of selenate is linked to methane oxidation. Metagenomic and metaproteomic analyses of the community revealed a novel species of Methylocystis as the most abundant methanotroph, which actively expressed proteins for oxygen-dependent methane oxidation and fermentation pathways, but lacked the genetic potential for selenate reduction. Pseudoxanthomonas, Piscinibacter, and Rhodocyclaceae populations appeared to be responsible for the observed selenate reduction using proteins initially annotated as periplasmic nitrate reductases, with fermentation by-products released by the methanotrophs as electron donors. The ability for the annotated nitrate reductases to reduce selenate was confirmed by gene knockout studies in an isolate of Pseudoxanthomonas. Overall, this study provides novel insights into the metabolic flexibility of the aerobic methanotrophs that likely allows them to thrive across natural oxygen gradients, and highlights the potential role for similar microbial consortia in linking methane and other biogeochemical cycles in environments where oxygen is limited.
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Affiliation(s)
- Ling-Dong Shi
- grid.13402.340000 0004 1759 700XMOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Pan-Long Lv
- grid.13402.340000 0004 1759 700XMOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Simon J. McIlroy
- grid.489335.00000000406180938Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology (QUT), Translational Research Institute, Woolloongabba, QLD Australia ,grid.1003.20000 0000 9320 7537Australian Centre for Ecogenomics, University of Queensland, Brisbane, QLD Australia
| | - Zhen Wang
- grid.13402.340000 0004 1759 700XMOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Xiao-Li Dong
- grid.22072.350000 0004 1936 7697Department of Geoscience, University of Calgary, Calgary, AB Canada
| | - Angela Kouris
- grid.22072.350000 0004 1936 7697Department of Geoscience, University of Calgary, Calgary, AB Canada
| | - Chun-Yu Lai
- grid.13402.340000 0004 1759 700XMOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China ,grid.1003.20000 0000 9320 7537Australian Centre for Ecogenomics, University of Queensland, Brisbane, QLD Australia
| | - Gene W. Tyson
- grid.489335.00000000406180938Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology (QUT), Translational Research Institute, Woolloongabba, QLD Australia
| | - Marc Strous
- grid.22072.350000 0004 1936 7697Department of Geoscience, University of Calgary, Calgary, AB Canada
| | - He-Ping Zhao
- grid.13402.340000 0004 1759 700XMOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
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12
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Pinel-Cabello M, Chapon V, Ruiz-Fresneda MA, Alpha-Bazin B, Berthomieu C, Armengaud J, Merroun ML. Delineation of cellular stages and identification of key proteins for reduction and biotransformation of Se(IV) by Stenotrophomonas bentonitica BII-R7. JOURNAL OF HAZARDOUS MATERIALS 2021; 418:126150. [PMID: 34111750 DOI: 10.1016/j.jhazmat.2021.126150] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 04/30/2021] [Accepted: 05/14/2021] [Indexed: 06/12/2023]
Abstract
The widespread use of selenium (Se) in technological applications (e.g., solar cells and electronic devices) has led to an accumulation of this metalloid in the environment to toxic levels. The newly described bacterial strain Stenotrophomonas bentonitica BII-R7 has been demonstrated to reduce mobile Se(IV) to Se(0)-nanoparticles (Se(0)NPs) and volatile species. Amorphous Se-nanospheres are reported to aggregate to form crystalline nanostructures and trigonal selenium. We investigated the molecular mechanisms underlying the biotransformation of Se(IV) to less toxic forms using differential shotgun proteomics analysis of S. bentonitica BII-R7 grown with or without sodium selenite for three different time-points. Results showed an increase in the abundance of several proteins involved in Se(IV) reduction and stabilization of Se(0)NPs, such as glutathione reductase, in bacteria grown with Se(IV), in addition to many proteins with transport functions, including RND (resistance-nodulation-division) systems, possibly facilitating Se uptake. Notably proteins involved in oxidative stress defense (e.g., catalase/peroxidase HPI) were also induced by Se exposure. Electron microscopy analyses confirmed the biotransformation of amorphous nanospheres to trigonal Se. Overall, our results highlight the potential of S. bentonitica in reducing the bioavailability of Se, which provides a basis both for the development of bioremediation strategies and the eco-friendly synthesis of biotechnological nanomaterials.
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Affiliation(s)
- M Pinel-Cabello
- Department of Microbiology, University of Granada, Campus Fuentenueva s/n, 18071 Granada, Spain.
| | - V Chapon
- CEA, CNRS, Aix-Marseille Université, BIAM, IPM, 13108 Saint-Paul-lez-Durance, France
| | - M A Ruiz-Fresneda
- Department of Microbiology, University of Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
| | - B Alpha-Bazin
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SPI, 30200 Bagnols sur Cèze, France
| | - C Berthomieu
- CEA, CNRS, Aix-Marseille Université, BIAM, IPM, 13108 Saint-Paul-lez-Durance, France
| | - J Armengaud
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SPI, 30200 Bagnols sur Cèze, France
| | - M L Merroun
- Department of Microbiology, University of Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
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13
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Huang C, Wang H, Shi X, Wang Y, Li P, Yin H, Shao Y. Two new selenite reducing bacterial isolates from paddy soil and the potential Se biofortification of paddy rice. ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:1465-1475. [PMID: 32880083 DOI: 10.1007/s10646-020-02273-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
Selenium (Se) is an essential element for human health. Se-enriched agricultural products can promote people's intake of Se. Microorganisms play an important role in Se cycling. In this study, two new bacterial strains were isolated from paddy soil and were identified as Chitinophaga sp. and Comamonas testosteroni, respectively. More than 44% and 39% of 1.0 mM selenite were reduced in 84 h by them using yeast extract as carbon source, respectively. Scanning electron microscope (SEM) and Energy dispersive X-ray spectrometry (EDS) results indicated that the reduction product of selenite was nanometer Se. These strains could promote the available Se in soil and the content of Se in rice plants in pot experiments. Organic combined Se in soils was increased up to 35%, accompanied by the 92% and 130% increase of Se in rice plants. To our best knowledge, this is the first report of Se reduction by Chitinophaga. This work might provide a prospective strategy for microbial fortification of Se in corps.
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Affiliation(s)
- Chunlei Huang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, PR China
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, PR China
- Zhejiang Institute of Geological Survey, Hangzhou, 311203, PR China
| | - Helin Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, PR China
| | - Xinyan Shi
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, PR China
| | - Yanhong Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, PR China
| | - Ping Li
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, PR China.
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, PR China.
| | - Hanqin Yin
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, PR China
- Zhejiang Institute of Geological Survey, Hangzhou, 311203, PR China
| | - Yixian Shao
- Zhejiang Institute of Geological Survey, Hangzhou, 311203, PR China
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14
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Dal Ferro N, De Mattia C, Gandini MA, Maucieri C, Stevanato P, Squartini A, Borin M. Green walls to treat kitchen greywater in urban areas: Performance from a pilot-scale experiment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 757:144189. [PMID: 33316535 DOI: 10.1016/j.scitotenv.2020.144189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 11/28/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
An increase in water use in urban areas is forcing scientists and policy makers to find alternative solutions for freshwater management, aimed at attaining integrated water resources management. Here, we tested in a 2-year experiment (June 2017-April 2019) the treatment performance of an innovative wall cascade constructed wetland (WCCW) system. The aim was to combine the multifunctional benefits of green walls (e.g. aesthetic, surface area requirements) with those of constructed wetland systems (e.g. high pollutants removal efficiencies, water recycling) to treat kitchen greywaters. The WCCW was a terraced system of six phytoremediation lines, each of which was composed of three plastic tanks (3 × 0.04 m3), filled with lightweight porous media, and vegetated with different ornamental species, namely Mentha aquatica L., Oenanthe javanica (Blume) DC., and Lysimachia nummularia L. Physicochemical (temperature, pH, electrical conductivity, dissolved oxygen, turbidity) and chemical parameters (chemical oxygen demand, biochemical oxygen demand, anionic surfactants, Kjeldahl, ammonium and nitric nitrogen, total orthophosphate) were monitored at a frequency of at least 15 days, depending on the season and WCCW management. Results showed that the WCCW significantly reduced the main water pollutants (e.g. organic compounds, nutrients), suggesting its potential application in urban environments for water recycling in the context of green infrastructures and ecological sanitation. A culture-independent taxonomic assessment of suspended bacterial communities before and after the treatment showed clear treatment-related shifts, being the functional ecology attributes changed according to changes in greywater chemical parameters. Future research should attempt to optimize the WCCW system management by regulating the nutrients balance to avoid macronutrients deficiency, and setting the most suitable water flow dynamics (hydraulic retention time, saturation-desaturation cycles) to improve the greywater treatment.
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Affiliation(s)
- Nicola Dal Ferro
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova, Viale dell'Universita' 16, 35020 Legnaro, Padova, Italy.
| | - Chiara De Mattia
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova, Viale dell'Universita' 16, 35020 Legnaro, Padova, Italy
| | - Mario Andres Gandini
- Department of Energy and Mechanics, Universidad Autónoma de Occidente, Calle 25 No. 115-85, Cali, Colombia
| | - Carmelo Maucieri
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova, Viale dell'Universita' 16, 35020 Legnaro, Padova, Italy
| | - Piergiorgio Stevanato
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova, Viale dell'Universita' 16, 35020 Legnaro, Padova, Italy
| | - Andrea Squartini
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova, Viale dell'Universita' 16, 35020 Legnaro, Padova, Italy
| | - Maurizio Borin
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova, Viale dell'Universita' 16, 35020 Legnaro, Padova, Italy
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15
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Zambonino MC, Quizhpe EM, Jaramillo FE, Rahman A, Santiago Vispo N, Jeffryes C, Dahoumane SA. Green Synthesis of Selenium and Tellurium Nanoparticles: Current Trends, Biological Properties and Biomedical Applications. Int J Mol Sci 2021; 22:989. [PMID: 33498184 PMCID: PMC7863925 DOI: 10.3390/ijms22030989] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/15/2021] [Accepted: 01/18/2021] [Indexed: 12/17/2022] Open
Abstract
The synthesis and assembly of nanoparticles using green technology has been an excellent option in nanotechnology because they are easy to implement, cost-efficient, eco-friendly, risk-free, and amenable to scaling up. They also do not require sophisticated equipment nor well-trained professionals. Bionanotechnology involves various biological systems as suitable nanofactories, including biomolecules, bacteria, fungi, yeasts, and plants. Biologically inspired nanomaterial fabrication approaches have shown great potential to interconnect microbial or plant extract biotechnology and nanotechnology. The present article extensively reviews the eco-friendly production of metalloid nanoparticles, namely made of selenium (SeNPs) and tellurium (TeNPs), using various microorganisms, such as bacteria and fungi, and plants' extracts. It also discusses the methodologies followed by materials scientists and highlights the impact of the experimental sets on the outcomes and shed light on the underlying mechanisms. Moreover, it features the unique properties displayed by these biogenic nanoparticles for a large range of emerging applications in medicine, agriculture, bioengineering, and bioremediation.
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Affiliation(s)
- Marjorie C. Zambonino
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí 100119, Ecuador; (M.C.Z.); (E.M.Q.); (F.E.J.); (N.S.V.)
| | - Ernesto Mateo Quizhpe
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí 100119, Ecuador; (M.C.Z.); (E.M.Q.); (F.E.J.); (N.S.V.)
| | - Francisco E. Jaramillo
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí 100119, Ecuador; (M.C.Z.); (E.M.Q.); (F.E.J.); (N.S.V.)
| | - Ashiqur Rahman
- Center for Midstream Management and Science, Lamar University, Beaumont, TX 77710, USA;
- Center for Advances in Water and Air Quality & The Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, TX 77710, USA;
| | - Nelson Santiago Vispo
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí 100119, Ecuador; (M.C.Z.); (E.M.Q.); (F.E.J.); (N.S.V.)
| | - Clayton Jeffryes
- Center for Advances in Water and Air Quality & The Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, TX 77710, USA;
| | - Si Amar Dahoumane
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí 100119, Ecuador; (M.C.Z.); (E.M.Q.); (F.E.J.); (N.S.V.)
- Department of Chemical Engineering, Polytechnique Montréal, C.P. 6079, Succ. Centre-ville, Montréal, QC H3C 3A7, Canada
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16
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Ojeda JJ, Merroun ML, Tugarova AV, Lampis S, Kamnev AA, Gardiner PHE. Developments in the study and applications of bacterial transformations of selenium species. Crit Rev Biotechnol 2020; 40:1250-1264. [PMID: 32854560 DOI: 10.1080/07388551.2020.1811199] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Microbial bio-transformations of the essential trace element selenium are now recognized to occur among a wide variety of microorganisms. These transformations are used to convert this element into its assimilated form of selenocysteine, which is at the active center of a number of key enzymes, and to produce selenium nanoparticles, quantum dots, metal selenides, and methylated selenium species that are indispensable for biotechnological and bioremediation applications. The focus of this review is to present the state-of-the-art of all aspects of the investigations into the bacterial transformations of selenium species, and to consider the characterization and biotechnological uses of these transformations and their products.
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Affiliation(s)
- Jesus J Ojeda
- College of Engineering, Swansea University, Systems and Process Engineering Centre, Swansea, UK
| | | | - Anna V Tugarova
- Laboratory of Biochemistry, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, Saratov, Russia
| | - Silvia Lampis
- Department of Biotechnology, University of Verona, Verona, Italy
| | - Alexander A Kamnev
- Laboratory of Biochemistry, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, Saratov, Russia
| | - Philip H E Gardiner
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
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17
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The small RNA chaperone Hfq is a critical regulator for bacterial biosynthesis of selenium nanoparticles and motility in Rahnella aquatilis. Appl Microbiol Biotechnol 2020; 104:1721-1735. [DOI: 10.1007/s00253-019-10231-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/11/2019] [Accepted: 10/31/2019] [Indexed: 02/08/2023]
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18
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Schiavon M, Nardi S, dalla Vecchia F, Ertani A. Selenium biofortification in the 21 st century: status and challenges for healthy human nutrition. PLANT AND SOIL 2020; 453:245-270. [PMID: 32836404 PMCID: PMC7363690 DOI: 10.1007/s11104-020-04635-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/06/2020] [Indexed: 05/04/2023]
Abstract
BACKGROUND Selenium (Se) is an essential element for mammals and its deficiency in the diet is a global problem. Plants accumulate Se and thus represent a major source of Se to consumers. Agronomic biofortification intends to enrich crops with Se in order to secure its adequate supply by people. SCOPE The goal of this review is to report the present knowledge of the distribution and processes of Se in soil and at the plant-soil interface, and of Se behaviour inside the plant in terms of biofortification. It aims to unravel the Se metabolic pathways that affect the nutritional value of edible plant products, various Se biofortification strategies in challenging environments, as well as the impact of Se-enriched food on human health. CONCLUSIONS Agronomic biofortification and breeding are prevalent strategies for battling Se deficiency. Future research addresses nanosized Se biofortification, crop enrichment with multiple micronutrients, microbial-integrated agronomic biofortification, and optimization of Se biofortification in adverse conditions. Biofortified food of superior nutritional quality may be created, enriched with healthy Se-compounds, as well as several other valuable phytochemicals. Whether such a food source might be used as nutritional intervention for recently emerged coronavirus infections is a relevant question that deserves investigation.
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Affiliation(s)
- Michela Schiavon
- Dipartimento di Agronomia, Animali, Alimenti, Risorse naturali e Ambiente (DAFNAE), Università di Padova, Viale dell’Università 16, 35020 Legnaro, PD Italy
| | - Serenella Nardi
- Dipartimento di Agronomia, Animali, Alimenti, Risorse naturali e Ambiente (DAFNAE), Università di Padova, Viale dell’Università 16, 35020 Legnaro, PD Italy
| | | | - Andrea Ertani
- Dipartimento di Scienze Agrarie, Università di Torino, Via Leonardo da Vinci, 44, 10095 Grugliasco, TO Italy
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19
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Fungal formation of selenium and tellurium nanoparticles. Appl Microbiol Biotechnol 2019; 103:7241-7259. [PMID: 31324941 PMCID: PMC6691031 DOI: 10.1007/s00253-019-09995-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 11/24/2022]
Abstract
The fungi Aureobasidium pullulans, Mortierella humilis, Trichoderma harzianum and Phoma glomerata were used to investigate the formation of selenium- and tellurium-containing nanoparticles during growth on selenium- and tellurium-containing media. Most organisms were able to grow on both selenium- and tellurium-containing media at concentrations of 1 mM resulting in extensive precipitation of elemental selenium and tellurium on fungal surfaces as observed by the red and black colour changes. Red or black deposits were confirmed as elemental selenium and tellurium, respectively. Selenium oxide and tellurium oxide were also found after growth of Trichoderma harzianum with 1 mM selenite and tellurite as well as the formation of elemental selenium and tellurium. The hyphal matrix provided nucleation sites for metalloid deposition with extracellular protein and extracellular polymeric substances localizing the resultant Se or Te nanoparticles. These findings are relevant to remedial treatments for selenium and tellurium and to novel approaches for selenium and tellurium biorecovery.
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20
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Bai YN, Wang XN, Lu YZ, Fu L, Zhang F, Lau TC, Zeng RJ. Microbial selenite reduction coupled to anaerobic oxidation of methane. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 669:168-174. [PMID: 30878925 DOI: 10.1016/j.scitotenv.2019.03.119] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/08/2019] [Accepted: 03/08/2019] [Indexed: 06/09/2023]
Abstract
Denitrifying anaerobic methane oxidation (DAMO) is the process of coupling the anaerobic oxidation of methane (AOM) with denitrification, which plays an important part in controlling the flow of methane in anoxic niches. In this study, we explored the feasibility of microbial selenite reduction using methane by DAMO culture. Isotopic 13CH4 and long-term experiments showed that selenite reduction was coupled to methane oxidation, and selenite was ultimately reduced to Se (0) by the analyses of scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The introduction of nitrate, the original electron acceptor in the DAMO culture, inhibited selenite reduction. Meanwhile, the microbial community of DAMO culture was significantly changed when the electron acceptor was changed from nitrate to selenite after long-term selenite reduction. High-throughput 16S rRNA gene sequencing indicated that Methylococcus (26%) became the predominant microbe performing selenite reduction and methane oxidation and the possible pathways of AOM accompanied with selenite reduction were proposed. This study revealed more potential relation during the biogeochemical cycle of carbon, nitrogen, and selenium.
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Affiliation(s)
- Ya-Nan Bai
- Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou, PR China; School of Life Sciences, University of Science and Technology of China, Hefei 230026, PR China
| | - Xiu-Ning Wang
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China
| | - Yong-Ze Lu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China
| | - Ling Fu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China
| | - Fang Zhang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
| | - Tai-Chu Lau
- Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou, PR China; State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Raymond J Zeng
- Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou, PR China; School of Life Sciences, University of Science and Technology of China, Hefei 230026, PR China; Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
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Wang D, Xia X, Wu S, Zheng S, Wang G. The essentialness of glutathione reductase GorA for biosynthesis of Se(0)-nanoparticles and GSH for CdSe quantum dot formation in Pseudomonas stutzeri TS44. JOURNAL OF HAZARDOUS MATERIALS 2019; 366:301-310. [PMID: 30530022 DOI: 10.1016/j.jhazmat.2018.11.092] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 10/21/2018] [Accepted: 11/22/2018] [Indexed: 05/22/2023]
Abstract
Pseudomonas stutzeri TS44 was able to aerobically reduce Se(IV) into SeNPs and transform Se(IV)/Cd(II) mixture into CdSe-QDs. The SeNPs and CdSe-QDs were systematically characterized by surface feature analyses, and the molecular mechanisms of SeNPs and CdSe-QD formation in P. stutzeri TS44 were characterized in detail. In vivo, under 2.5 mmol/L Se(IV) exposure, GorA was essential for catalyzing of Se(IV) reduction rate decreased by 67% when the glutathione reductase gene gorA was disrupted, but it was not decreased in the glutathione synthesis rate-limiting gene gshA mutated strain compared to the wild type. The complemented strains restored the phenotypes. While under low amount of Se(IV) (0.5 mmol/L), GSH played an important role for Se(IV) reduction. In vitro, GorA catalyzed Se(IV) reduction with NADPH as the electron donor (Vmax of 3.947 ± 0.1061 μmol/min/mg protein under pH 7.0 and 28℃). In addition, CdSe-QDs were successfully synthesized by a one-step method in which Se(IV) and Cd(II) were added to bacterial culture simultaneously. GSH rather than GorA is necessary for CdSe-QD formation in vivo and in vitro. In conclusion, the results provide new findings showing that GorA functions as a selenite reductase under high amount Se(IV) and GSH is essential for bacterial CdSe-QD synthesis.
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Affiliation(s)
- Dan Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Xian Xia
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Shijuan Wu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Shixue Zheng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Gejiao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
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Wang Y, Shu X, Hou J, Lu W, Zhao W, Huang S, Wu L. Selenium Nanoparticle Synthesized by Proteus mirabilis YC801: An Efficacious Pathway for Selenite Biotransformation and Detoxification. Int J Mol Sci 2018; 19:ijms19123809. [PMID: 30501097 PMCID: PMC6321198 DOI: 10.3390/ijms19123809] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 01/19/2023] Open
Abstract
Selenite is extremely biotoxic, and as a result of this, exploitation of microorganisms able to reduce selenite to non-toxic elemental selenium (Se0) has attracted great interest. In this study, a bacterial strain exhibiting extreme tolerance to selenite (up to 100 mM) was isolated from the gut of adult Monochamus alternatus and identified as Proteus mirabilis YC801. This strain demonstrated efficient transformation of selenite into red selenium nanoparticles (SeNPs) by reducing nearly 100% of 1.0 and 5.0 mM selenite within 42 and 48 h, respectively. Electron microscopy and energy dispersive X-ray analysis demonstrated that the SeNPs were spherical and primarily localized extracellularly, with an average hydrodynamic diameter of 178.3 ± 11.5 nm. In vitro selenite reduction activity assays and real-time PCR indicated that thioredoxin reductase and similar proteins present in the cytoplasm were likely to be involved in selenite reduction, and that NADPH or NADH served as electron donors. Finally, Fourier-transform infrared spectral analysis confirmed the presence of protein and lipid residues on the surfaces of SeNPs. This is the first report on the capability of P. mirabilis to reduce selenite to SeNPs. P. mirabilis YC801 might provide an eco-friendly approach to bioremediate selenium-contaminated soil/water, as well as a bacterial catalyst for the biogenesis of SeNPs.
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Affiliation(s)
- Yuting Wang
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- The Sericultural Research Institute, Anhui Academy of Agricultural Science, Hefei 230061, China.
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China.
| | - Xian Shu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China.
| | - Jinyan Hou
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Weili Lu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Anhui Key Laboratory of Bioactivity of Natural Products, School of Pharmacy, Anhui Medical University, Hefei 230032, China.
| | - Weiwei Zhao
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Shengwei Huang
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Anhui Key Laboratory of Bioactivity of Natural Products, School of Pharmacy, Anhui Medical University, Hefei 230032, China.
| | - Lifang Wu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China.
- Anhui Key Laboratory of Bioactivity of Natural Products, School of Pharmacy, Anhui Medical University, Hefei 230032, China.
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Tan Y, Wang Y, Wang Y, Xu D, Huang Y, Wang D, Wang G, Rensing C, Zheng S. Novel mechanisms of selenate and selenite reduction in the obligate aerobic bacterium Comamonas testosteroni S44. JOURNAL OF HAZARDOUS MATERIALS 2018; 359:129-138. [PMID: 30014908 DOI: 10.1016/j.jhazmat.2018.07.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 07/02/2018] [Accepted: 07/03/2018] [Indexed: 06/08/2023]
Abstract
Selenium oxyanion reduction is an effective detoxification or/and assimilation processes in organisms, but little is known the mechanisms in aerobic bacteria. Aerobic Comamonas testosteroni S44 reduces Se(VI)/Se(IV) to less-toxic elemental selenium nanoparticles (SeNPs). For Se(VI) reduction, sulfate and Se(VI) reduction displayed a competitive relationship. When essential sulfate reducing genes were respectively disrupted, Se(VI) was not reduced to red-colored SeNPs. Consequently, Se(VI) reduction was catalyzed by enzymes of the sulfate reducing pathway. For Se(IV) reduction, one of the potential periplasm molybdenum oxidoreductase named SerT was screened and further used to analyze Se(IV) reduction. Compared to the wild type and the complemented mutant strain, the ability of Se(IV) reduction was reduced 75% in the deletion mutant ΔserT. Moreover, the Se(IV) reduction rate was significantly enhanced when the gene serT was overexpressed in Escherichia coli W3110. In addition, Se(IV) was reduced to SeNPs by the purified SerT with the presence of NADPH as the electron donor in vitro, showing a Vmax of 61 nmol/min·mg and a Km of 180 μmol/L. A model of Se(VI)/Se(IV) reduction was generated in aerobic C. testosteroni S44. This work provides new insights into the molecular mechanisms of Se(VI)/Se(IV) reduction activities in aerobic bacteria.
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Affiliation(s)
- Yuanqing Tan
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Yuantao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Yu Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Ding Xu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Yeting Huang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Dan Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Gejiao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Christopher Rensing
- Institute of Environmental Microbiology, College of Resources and Environment, Fujian Agriculture & Forestry University, Fuzhou, Fujian 350002, PR China
| | - Shixue Zheng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China.
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Wang Y, Shu X, Zhou Q, Fan T, Wang T, Chen X, Li M, Ma Y, Ni J, Hou J, Zhao W, Li R, Huang S, Wu L. Selenite Reduction and the Biogenesis of Selenium Nanoparticles by Alcaligenesfaecalis Se03 Isolated from the Gut of Monochamus alternatus (Coleoptera: Cerambycidae). Int J Mol Sci 2018; 19:ijms19092799. [PMID: 30227664 PMCID: PMC6164237 DOI: 10.3390/ijms19092799] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 09/14/2018] [Accepted: 09/14/2018] [Indexed: 02/05/2023] Open
Abstract
In this study, a bacterial strain exhibiting high selenite (Na2SeO3) tolerance and reduction capacity was isolated from the gut of Monochamus alternatus larvae and identified as Alcaligenes faecalis Se03. The isolate exhibited extreme tolerance to selenite (up to 120 mM) when grown aerobically. In the liquid culture medium, it was capable of reducing nearly 100% of 1.0 and 5.0 mM Na2SeO3 within 24 and 42 h, respectively, leading to the formation of selenium nanoparticles (SeNPs). Electron microscopy and energy dispersive X-ray analysis demonstrated that A. faecalis Se03 produced spherical electron-dense SeNPs with an average hydrodynamic diameter of 273.8 ± 16.9 nm, localized mainly in the extracellular space. In vitro selenite reduction activity and real-time PCR indicated that proteins such as sulfite reductase and thioredoxin reductase present in the cytoplasm were likely to be involved in selenite reduction and the SeNPs synthesis process in the presence of NADPH or NADH as electron donors. Finally, using Fourier-transform infrared spectrometry, protein and lipid residues were detected on the surface of the biogenic SeNPs. Based on these observations, A. faecalis Se03 has the potential to be an eco-friendly candidate for the bioremediation of selenium-contaminated soil/water and a bacterial catalyst for the biogenesis of SeNPs.
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Affiliation(s)
- Yuting Wang
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China.
- The Sericultural Research Institute, Anhui Academy of Agricultural Science, Hefei 230061, China.
| | - Xian Shu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China.
| | - Qing Zhou
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China.
| | - Tao Fan
- The Sericultural Research Institute, Anhui Academy of Agricultural Science, Hefei 230061, China.
| | - Taichu Wang
- The Sericultural Research Institute, Anhui Academy of Agricultural Science, Hefei 230061, China.
| | - Xue Chen
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China.
| | - Minghao Li
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China.
- Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Yuhan Ma
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Jun Ni
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Jinyan Hou
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Weiwei Zhao
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Ruixue Li
- The Sericultural Research Institute, Anhui Academy of Agricultural Science, Hefei 230061, China.
| | - Shengwei Huang
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
| | - Lifang Wu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
- The Sericultural Research Institute, Anhui Academy of Agricultural Science, Hefei 230061, China.
- Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
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He Y, Xiang Y, Zhou Y, Yang Y, Zhang J, Huang H, Shang C, Luo L, Gao J, Tang L. Selenium contamination, consequences and remediation techniques in water and soils: A review. ENVIRONMENTAL RESEARCH 2018; 164:288-301. [PMID: 29554620 DOI: 10.1016/j.envres.2018.02.037] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 02/04/2018] [Accepted: 02/26/2018] [Indexed: 05/21/2023]
Abstract
Selenium (Se) contamination in surface and ground water in numerous river basins has become a critical problem worldwide in recent years. The exposure to Se, either direct consumption of Se or indirectly may be fatal to the human health because of its toxicity. The review begins with an introduction of Se chemistry, distribution and health threats, which are essential to the remediation techniques. Then, the review provides the recent and common removal techniques for Se, including reduction techniques, phytoremediation, bioremediation, coagulation-flocculation, electrocoagulation (EC), electrochemical methods, adsorption, coprecipitation, electrokinetics, membrance technology, and chemical precipitation. Removal techniques concentrate on the advantages, drawbacks and the recent achievements of each technique. The review also takes an overall consideration of experimental conditions, comparison criteria and economic aspects.
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Affiliation(s)
- Yangzhuo He
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Yujia Xiang
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Yaoyu Zhou
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China.
| | - Yuan Yang
- 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
| | - Cui Shang
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Lin Luo
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Jun Gao
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Lin Tang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China
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26
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Formation of Se(0), Te(0), and Se(0)-Te(0) nanostructures during simultaneous bioreduction of selenite and tellurite in a UASB reactor. Appl Microbiol Biotechnol 2018; 102:2899-2911. [PMID: 29399711 DOI: 10.1007/s00253-018-8781-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 01/11/2018] [Accepted: 01/12/2018] [Indexed: 10/18/2022]
Abstract
Simultaneous removal of selenite and tellurite from synthetic wastewater was achieved through microbial reduction in a lab-scale upflow anaerobic sludge blanket reactor operated with 12 h hydraulic retention time at 30 °C and pH 7 for 120 days. Lactate was supplied as electron donor at an organic loading rate of 528 or 880 mg COD L-1 day-1. The reactor was initially fed with a synthetic influent containing 0.05 mM selenite and tellurite each (phase I, day 1-60) and subsequently with 0.1 mM selenite and tellurite each (phase II, day 61-120). At the end of phase I, selenite and tellurite removal efficiencies were 93 and 96%, respectively. The removal percentage dropped to 87 and 81% for selenite and tellurite, respectively, at the beginning of phase II because of the increased influent concentrations. The removal efficiencies of both selenite and tellurite were gradually restored within 20 days and stabilized at ≥ 97% towards the end of the experiment. Powder X-ray diffraction and Raman spectroscopy confirmed the formation of biogenic Se(0), Te(0), and Se(0)-Te(0) nanostructures. Scanning transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy showed aggregates comprising of Se(0), Te(0), and Se-Te nanostructures embedded in a layer of extracellular polymeric substances (EPS). Infrared spectroscopy confirmed the presence of chemical signatures of the EPS which capped the nanoparticle aggregates that had been formed and immobilized in the granular sludge. This study suggests a model for technologies for remediation of effluents containing Se and Te oxyanions coupled with biorecovery of bimetal(loid) nanostructures.
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Xia X, Wu S, Li N, Wang D, Zheng S, Wang G. Novel bacterial selenite reductase CsrF responsible for Se(IV) and Cr(VI) reduction that produces nanoparticles in Alishewanella sp. WH16-1. JOURNAL OF HAZARDOUS MATERIALS 2018; 342:499-509. [PMID: 28881274 DOI: 10.1016/j.jhazmat.2017.08.051] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 07/25/2017] [Accepted: 08/16/2017] [Indexed: 06/07/2023]
Abstract
Alishewanella sp. WH16-1 is a facultative anaerobic bacterium isolated from mining soil. Under aerobic conditions, this bacterium efficiently reduces selenite and chromate. A flavoprotein showing 37% amino acid identity to E. coli chromate reductase ChrR was identified from the genome (named CsrF). Gene mutation and complementation along with heterologous expression revealed the ability of CsrF to reduce selenite and chromate in vivo. The purified CsrF was yellow and showed an absorption spectra similar to that of FMN. The molecular weight of CsrF was 23,906 for the monomer and 47,960 for the dimer. In vitro, CsrF catalyzes the reduction of Se(IV) and Cr(VI) using NAD(P)H as cofactors with optimal condition of pH 7.0 and temperature of 30-37°C. This enzyme also catalyze the reduction of sulfate and ferric iron but not arsenate and nitrate. Using NADPH as its electron donor, the Km for the reduction of Se(IV) and Cr(VI) was 204.1±27.91 and 250.6±23.46μmol/L, respectively. Site-directed mutagenesis showed that Arg13 and Gly113 were essential for the reduction of Se(IV) and Cr(VI). The products of the reduction of Se(IV) and Cr(VI) were Se(0)- and Cr(III)-nanoparticles, respectively. To our knowledge, CsrF is a novel and well-characterized bacterial aerobic selenite reductase.
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Affiliation(s)
- Xian Xia
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Shijuan Wu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Nuohan Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Dan Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Shixue Zheng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China
| | - Gejiao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China.
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28
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Li J, Guo W, Shi M, Cao Y, Wang G. High-quality-draft genomic sequence of Paenibacillus ferrarius CY1 T with the potential to bioremediate Cd, Cr and Se contamination. Stand Genomic Sci 2017; 12:60. [PMID: 29046739 PMCID: PMC5634878 DOI: 10.1186/s40793-017-0273-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 09/21/2017] [Indexed: 11/23/2022] Open
Abstract
Paenibacillus ferrarius CY1T (= KCTC 33419T = CCTCC AB2013369T) is a Gram-positive, aerobic, endospore-forming, motile and rod-shaped bacterium isolated from iron mineral soil. This bacterium reduces sulfate (SO42-) to S2-, which reacts with Cd(II) to generate precipitated CdS. It also reduces the toxic chromate [Cr(VI)] and selenite [Se(VI)] to the less bioavailable chromite [Cr(III)] and selenium (Se0), respectively. Thus, strain CY1T has the potential to bioremediate Cd, Cr and Se contamination, which is the main reason for the interest in sequencing its genome. Here we describe the features of strain CY1T, together with the draft genome sequence and its annotation. The 9,184,169 bp long genome exhibits a G + C content of 45.6%, 7909 protein-coding genes and 81 RNA genes. Nine putative Se(IV)-reducing genes, five putative Cr(VI) reductase and nine putative sulfate-reducing genes were identified in the genome.
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Affiliation(s)
- Jingxin Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 People’s Republic of China
| | - Wei Guo
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 People’s Republic of China
| | - Manman Shi
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 People’s Republic of China
| | - Yajing Cao
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 People’s Republic of China
| | - Gejiao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 People’s Republic of China
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29
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Khoei NS, Lampis S, Zonaro E, Yrjälä K, Bernardi P, Vallini G. Insights into selenite reduction and biogenesis of elemental selenium nanoparticles by two environmental isolates of Burkholderia fungorum. N Biotechnol 2016; 34:1-11. [PMID: 27717878 DOI: 10.1016/j.nbt.2016.10.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 07/11/2016] [Accepted: 10/03/2016] [Indexed: 11/30/2022]
Abstract
Microorganisms capable of transforming toxic selenium oxyanions into non-toxic elemental selenium (Se°) may be considered as biocatalysts for the production of selenium nanoparticles (SeNPs), eventually exploitable in different biotechnological applications. Two Burkholderia fungorum strains (B. fungorum DBT1 and B. fungorum 95) were monitored during their growth for both capacity and efficiency of selenite (SeO32-) reduction and elemental selenium formation. Both strains are environmental isolates in origin: B. fungorum DBT1 was previously isolated from an oil refinery drainage, while B. fungorum 95 has been enriched from inner tissues of hybrid poplars grown in a soil contaminated by polycyclic aromatic hydrocarbons. Our results showed that B. fungorum DBT1 is able to reduce 0.5mM SeO32- to Se° when cultured aerobically in liquid medium at 27°C, while B. fungorum 95 can reduce more than 1mM SeO32- to Se° within 96h under the same growth conditions, with the appearance of SeNPs in cultures of both bacterial strains. Biogenic SeNPs were spherical, with pH-dependent charge and an average hydrodynamic diameter of 170nm and 200nm depending on whether they were produced by B. fungorum 95 or B. fungorum DBT1, respectively. Electron microscopy analyses evidenced that Se nanoparticles occurred intracellularly and extracellularly. The mechanism of SeNPs formation can be tentatively attributed to cytoplasmic enzymatic activation mediated by electron donors. Biogenic nanoparticles were then probably released outside the bacterial cells as a consequence of a secretory process or cell lysis. Nevertheless, formation of elemental selenium nanoparticles under aerobic conditions by B. fungorum DBT1 and B. fungorum 95 is likely due to intracellular reduction mechanisms. Biomedical and other high tech sectors might exploit these biogenic nanoparticles in the near future, once fully characterized and tested for their multiple properties.
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Affiliation(s)
- Nazanin Seyed Khoei
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy.
| | - Silvia Lampis
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy.
| | - Emanuele Zonaro
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Kim Yrjälä
- MEM-group, Department of Biosciences, University of Helsinki, 00014 Helsinki, Finland
| | - Paolo Bernardi
- Department of Neurological and Movement Sciences, University of Verona, Strada Le Grazie 8, 37134 Verona, Italy
| | - Giovanni Vallini
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy
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Tan Y, Yao R, Wang R, Wang D, Wang G, Zheng S. Reduction of selenite to Se(0) nanoparticles by filamentous bacterium Streptomyces sp. ES2-5 isolated from a selenium mining soil. Microb Cell Fact 2016; 15:157. [PMID: 27630128 PMCID: PMC5024524 DOI: 10.1186/s12934-016-0554-z] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Accepted: 09/07/2016] [Indexed: 11/10/2022] Open
Abstract
Background Selenium (Se) is an essential trace element in living systems. Microorganisms play a pivotal role in the selenium cycle both in life and in environment. Different bacterial strains are able to reduce Se(IV) (selenite) and (or) Se(VI) (selenate) to less toxic Se(0) with the formation of Se nanoparticles (SeNPs). The biogenic SeNPs have exhibited promising application prospects in medicine, biosensors and environmental remediation. These microorganisms might be explored as potential biofactories for synthesis of metal(loid) nanoparticles. Results A strictly aerobic, branched actinomycete strain, ES2-5, was isolated from a selenium mining soil in southwest China, identified as Streptomyces sp. based on 16S rRNA gene sequence, physiologic and morphologic characteristics. Both SEM and TEM-EDX analysis showed that Se(IV) was reduced to Se(0) with the formation of SeNPs as a linear chain in the cytoplasm. The sizes of the SeNPs were in the range of 50–500 nm. The cellular concentration of glutathione per biomass decreased along with Se(IV) reduction, and no SeNPs were observed in different sub-cellular fractions in presence of NADPH or NADH as an electron donor, indicating glutathione is most possibly involved in vivo Se(IV) reduction. Strain ES2-5 was resistant to some heavy metal(loid)s such as Se(IV), Cr(VI) and Zn(II) with minimal inhibitory concentration of 50, 80 and 1.5 mM, respectively. Conclusions The reducing mechanism of Se(IV) to elemental SeNPs under aerobic condition was investigated in a filamentous strain of Streptomyces. Se(IV) reduction is mediated by glutathione and then SeNPs synthesis happens inside of the cells. The SeNPs are released via hypha lysis or fragmentation. It would be very useful in Se bioremediation if Streptomyces sp. ES2-5 is applied to the contaminated site because of its ability of spore reproduction, Se(IV) reduction, and adaptation in soil.
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Affiliation(s)
- Yuanqing Tan
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Rong Yao
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Rui Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Dan Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Gejiao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Shixue Zheng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
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Fisher B, Yarmolinsky D, Abdel-Ghany S, Pilon M, Pilon-Smits EA, Sagi M, Van Hoewyk D. Superoxide generated from the glutathione-mediated reduction of selenite damages the iron-sulfur cluster of chloroplastic ferredoxin. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 106:228-35. [PMID: 27182957 DOI: 10.1016/j.plaphy.2016.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 05/04/2016] [Accepted: 05/05/2016] [Indexed: 05/23/2023]
Abstract
Selenium assimilation in plants is facilitated by several enzymes that participate in the transport and assimilation of sulfate. Manipulation of genes that function in sulfur metabolism dramatically affects selenium toxicity and accumulation. However, it has been proposed that selenite is not reduced by sulfite reductase. Instead, selenite can be non-enzymatically reduced by glutathione, generating selenodiglutathione and superoxide. The damaging effects of superoxide on iron-sulfur clusters in cytosolic and mitochondrial proteins are well known. However, it is unknown if superoxide damages chloroplastic iron-sulfur proteins. The goals of this study were twofold: to determine whether decreased activity of sulfite reductase impacts selenium tolerance in Arabidopsis, and to determine if superoxide generated from the glutathione-mediated reduction of selenite damages the iron-sulfur cluster of ferredoxin. Our data demonstrate that knockdown of sulfite reductase in Arabidopsis does not affect selenite tolerance or selenium accumulation. Additionally, we provide in vitro evidence that the non-enzymatic reduction of selenite damages the iron-sulfur cluster of ferredoxin, a plastidial protein that is an essential component of the photosynthetic light reactions. Damage to ferredoxin's iron-sulfur cluster was associated with formation of apo-ferredoxin and impaired activity. We conclude that if superoxide damages iron-sulfur clusters of ferredoxin in planta, then it might contribute to photosynthetic impairment often associated with abiotic stress, including toxic levels of selenium.
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Affiliation(s)
- Brian Fisher
- Coastal Carolina University, Biology Department, Conway, SC, 29526, USA.
| | - Dmitry Yarmolinsky
- Ben-Gurion University, Blaustein Institutes for Desert Research, Beer Sheva, Israel.
| | - Salah Abdel-Ghany
- Colorado State University, Biology Department, Fort Collins, CO, 80523, USA.
| | - Marinus Pilon
- Colorado State University, Biology Department, Fort Collins, CO, 80523, USA.
| | | | - Moshe Sagi
- Ben-Gurion University, Blaustein Institutes for Desert Research, Beer Sheva, Israel.
| | - Doug Van Hoewyk
- Coastal Carolina University, Biology Department, Conway, SC, 29526, USA.
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Microbial Transformations of Selenium Species of Relevance to Bioremediation. Appl Environ Microbiol 2016; 82:4848-59. [PMID: 27260359 DOI: 10.1128/aem.00877-16] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Selenium species, particularly the oxyanions selenite (SeO3 (2-)) and selenate (SeO4 (2-)), are significant pollutants in the environment that leach from rocks and are released by anthropogenic activities. Selenium is also an essential micronutrient for organisms across the tree of life, including microorganisms and human beings, particularly because of its presence in the 21st genetically encoded amino acid, selenocysteine. Environmental microorganisms are known to be capable of a range of transformations of selenium species, including reduction, methylation, oxidation, and demethylation. Assimilatory reduction of selenium species is necessary for the synthesis of selenoproteins. Dissimilatory reduction of selenate is known to support the anaerobic respiration of a number of microorganisms, and the dissimilatory reduction of soluble selenate and selenite to nanoparticulate elemental selenium greatly reduces the toxicity and bioavailability of selenium and has a major role in bioremediation and potentially in the production of selenium nanospheres for technological applications. Also, microbial methylation after reduction of Se oxyanions is another potentially effective detoxification process if limitations with low reaction rates and capture of the volatile methylated selenium species can be overcome. This review discusses microbial transformations of different forms of Se in an environmental context, with special emphasis on bioremediation of Se pollution.
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Nguyen VK, Park Y, Yu J, Lee T. Microbial selenite reduction with organic carbon and electrode as sole electron donor by a bacterium isolated from domestic wastewater. BIORESOURCE TECHNOLOGY 2016; 212:182-189. [PMID: 27099943 DOI: 10.1016/j.biortech.2016.04.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 04/02/2016] [Accepted: 04/10/2016] [Indexed: 06/05/2023]
Abstract
Selenium is said to be multifaceted element because it is essential at a low concentration but very toxic at an elevated level. For the purpose of screening a potential microorganism for selenite bioremediation, we isolated a bacterium, named strain THL1, which could perform both heterotrophic selenite reduction, using organic carbons such as acetate, lactate, propionate, and butyrate as electron donors under microaerobic condition, and electrotrophic selenite reduction, using an electrode polarized at -0.3V (vs. standard hydrogen electrode) as the sole electron donor under anaerobic condition. This bacterium determined to be a new strain of the genus Cronobacter, could remove selenite with an efficiency of up to 100%. This study is the first demonstration on a pure culture could take up electrons from an electrode to perform selenite reduction. The selenium nanoparticles produced by microbial selenite reduction might be considered for recovery and use in the nanotechnology industry.
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Affiliation(s)
- Van Khanh Nguyen
- Department of Civil and Environmental Engineering, Pusan National University, Pusan 609-735, Republic of Korea
| | - Younghyun Park
- Department of Civil and Environmental Engineering, Pusan National University, Pusan 609-735, Republic of Korea
| | - Jaecheul Yu
- Department of Civil and Environmental Engineering, Pusan National University, Pusan 609-735, Republic of Korea
| | - Taeho Lee
- Department of Civil and Environmental Engineering, Pusan National University, Pusan 609-735, Republic of Korea.
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Gonzalez-Gil G, Lens PNL, Saikaly PE. Selenite Reduction by Anaerobic Microbial Aggregates: Microbial Community Structure, and Proteins Associated to the Produced Selenium Spheres. Front Microbiol 2016; 7:571. [PMID: 27199909 PMCID: PMC4844624 DOI: 10.3389/fmicb.2016.00571] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 04/05/2016] [Indexed: 12/22/2022] Open
Abstract
Certain types of anaerobic granular sludge, which consists of microbial aggregates, can reduce selenium oxyanions. To envisage strategies for removing those oxyanions from wastewater and recovering the produced elemental selenium (Se(0)), insights into the microbial community structure and synthesis of Se(0) within these microbial aggregates are required. High-throughput sequencing showed that Veillonellaceae (c.a. 20%) and Pseudomonadaceae (c.a.10%) were the most abundant microbial phylotypes in selenite reducing microbial aggregates. The majority of the Pseudomonadaceae sequences were affiliated to the genus Pseudomonas. A distinct outer layer (∼200 μm) of selenium deposits indicated that bioreduction occurred in the outer zone of the microbial aggregates. In that outer layer, SEM analysis showed abundant intracellular and extracellular Se(0) (nano)spheres, with some cells having high numbers of intracellular Se(0) spheres. Electron tomography showed that microbial cells can harbor a single large intracellular sphere that stretches the cell body. The Se(0) spheres produced by the microorganisms were capped with organic material. X-ray photoelectron spectroscopy (XPS) analysis of extracted Se(0) spheres, combined with a mathematical approach to analyzing XPS spectra from biological origin, indicated that proteins and lipids were components of the capping material associated to the Se(0) spheres. The most abundant proteins associated to the spheres were identified by proteomic analysis. Most of the proteins or peptide sequences capping the Se(0) spheres were identified as periplasmic outer membrane porins and as the cytoplasmic elongation factor Tu protein, suggesting an intracellular formation of the Se(0) spheres. In view of these and previous findings, a schematic model for the synthesis of Se(0) spheres by the microorganisms inhabiting the granular sludge is proposed.
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Affiliation(s)
- Graciela Gonzalez-Gil
- Division of Biological and Environmental Sciences and Engineering, Water Desalination and Reuse Center, King Abdullah University of Science and TechnologyThuwal, Saudi Arabia; Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water EducationDelft, Netherlands
| | - Piet N L Lens
- Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education Delft, Netherlands
| | - Pascal E Saikaly
- Division of Biological and Environmental Sciences and Engineering, Water Desalination and Reuse Center, King Abdullah University of Science and Technology Thuwal, Saudi Arabia
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Lai CY, Wen LL, Zhang Y, Luo SS, Wang QY, Luo YH, Chen R, Yang X, Rittmann BE, Zhao HP. Autotrophic antimonate bio-reduction using hydrogen as the electron donor. WATER RESEARCH 2016; 88:467-474. [PMID: 26519630 DOI: 10.1016/j.watres.2015.10.042] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 10/09/2015] [Accepted: 10/19/2015] [Indexed: 06/05/2023]
Abstract
Antimony (Sb), a toxic metalloid, is soluble as antimonate (Sb(V)). While bio-reduction of Sb(V) is an effective Sb-removal approach, its bio-reduction has been coupled to oxidation of only organic electron donors. In this study, we demonstrate, for the first time, the feasibility of autotrophic microbial Sb(V) reduction using hydrogen gas (H2) as the electron donor without extra organic carbon source. SEM and EDS analysis confirmed the production of the mineral precipitate Sb2O3. When H2 was utilized as the electron donor, the consortium was able to fully reduce 650 μM of Sb(V) to Sb(III) in 10 days, a rate comparable to the culture using lactate as the electron donor. The H2-fed culture directed a much larger fraction of it donor electrons to Sb(V) reduction than did the lactate-fed culture. While 98% of the electrons from H2 were used to reduce Sb(V) by the H2-fed culture, only 12% of the electrons from lactate was used to reduce Sb(V) by the lactate-fed culture. The rest of the electrons from lactate went to acetate and propionate through fermentation, to methane through methanogenesis, and to biomass synthesis. High-throughput sequencing confirmed that the microbial community for the lactate-fed culture was much more diverse than that for the H2-fed culture, which was dominated by a short rod-shaped phylotype of Rhizobium (α-Protobacteria) that may have been active in Sb(V) reduction.
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Affiliation(s)
- Chun-Yu Lai
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Li-Lian Wen
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Yin Zhang
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Shan-Shan Luo
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Qing-Ying Wang
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Yi-Hao Luo
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Ran Chen
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Xiaoe Yang
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Bruce E Rittmann
- Swette Center for Environmental Biotechnology, Biodesign Institute at Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701 USA
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China.
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Lusa M, Bomberg M, Aromaa H, Knuutinen J, Lehto J. The microbial impact on the sorption behaviour of selenite in an acidic, nutrient-poor boreal bog. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2015; 147:85-96. [PMID: 26048060 DOI: 10.1016/j.jenvrad.2015.05.014] [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: 02/27/2015] [Revised: 05/12/2015] [Accepted: 05/13/2015] [Indexed: 06/04/2023]
Abstract
(79)Se is among the most important long lived radionuclides in spent nuclear fuel and selenite, SeO3(2-), is its typical form in intermediate redox potential. The sorption behaviour of selenite and the bacterial impact on the selenite sorption in a 7-m-deep profile of a nutrient-poor boreal bog was studied using batch sorption experiments. The batch distribution coefficient (Kd) values of selenite decreased as a function of sampling depth and highest Kd values, 6600 L/kg dry weight (DW), were observed in the surface moss and the lowest in the bottom clay at 1700 L/kg DW. The overall maximum sorption was observed at pH between 3 and 4 and the Kd values were significantly higher in unsterilized compared to sterilized samples. The removal of selenite from solution by Pseudomonas sp., Burkholderia sp., Rhodococcus sp. and Paenibacillus sp. strains isolated from the bog was affected by incubation temperature and time. In addition, the incubation of sterilized surface moss, subsurface peat and gyttja samples with added bacteria effectively removed selenite from the solution and on average 65% of selenite was removed when Pseudomonas sp. or Burkholderia sp. strains were used. Our results demonstrate the important role of bacteria for the removal of selenite from the solution phase in the bog environment, having a high organic matter content and a low pH.
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Affiliation(s)
- M Lusa
- Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland.
| | - M Bomberg
- VTT Technical Research Centre of Finland, P.O. Box 1000, 02044 VTT, Finland
| | - H Aromaa
- Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland
| | - J Knuutinen
- Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland
| | - J Lehto
- Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland
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Draft Genome Sequence of Se(IV)-Reducing Bacterium Pseudomonas migulae ES3-33. GENOME ANNOUNCEMENTS 2015; 3:3/3/e00406-15. [PMID: 25953191 PMCID: PMC4424307 DOI: 10.1128/genomea.00406-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Pseudomonas migulae ES3-33 is a Gram-negative strain that strongly reduces Se(IV) and was isolated from a selenium mining area in Enshi, southwest China. Here we present the draft genome of this strain containing potential genes involved in selenite reduction and a large number of genes encoding resistances to copper and antibiotics.
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Zheng S, Su J, Wang L, Yao R, Wang D, Deng Y, Wang R, Wang G, Rensing C. Selenite reduction by the obligate aerobic bacterium Comamonas testosteroni S44 isolated from a metal-contaminated soil. BMC Microbiol 2014; 14:204. [PMID: 25098921 PMCID: PMC4236595 DOI: 10.1186/s12866-014-0204-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 07/18/2014] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Selenium (Se) is an essential trace element in most organisms but has to be carefully handled since there is a thin line between beneficial and toxic concentrations. Many bacteria have the ability to reduce selenite (Se(IV)) and (or) selenate (Se(VI)) to red elemental selenium that is less toxic. RESULTS A strictly aerobic bacterium, Comamonas testosteroni S44, previously isolated from metal(loid)-contaminated soil in southern China, reduced Se(IV) to red selenium nanoparticles (SeNPs) with sizes ranging from 100 to 200 nm. Both energy dispersive X-ray Spectroscopy (EDX or EDS) and EDS Elemental Mapping showed no element Se and SeNPs were produced inside cells whereas Se(IV) was reduced to red-colored selenium in the cytoplasmic fraction in presence of NADPH. Tungstate inhibited Se(VI) but not Se(IV) reduction, indicating the Se(IV)-reducing determinant does not contain molybdenum as co-factor. Strain S44 was resistant to multiple heavy and transition metal(loid)s such as Se(IV), As(III), Cu(II), and Cd(II) with minimal inhibitory concentrations (MIC) of 100 mM, 20 mM, 4 mM, and 0.5 mM, respectively. Disruption of iscR encoding a transcriptional regulator negatively impacted cellular growth and subsequent resistance to multiple heavy metal(loid)s. CONCLUSIONS C. testosteroni S44 could be very useful for bioremediation in heavy metal(loid) polluted soils due to the ability to both reduce toxic Se(VI) and Se(IV) to non-toxic Se (0) under aerobic conditions and to tolerate multiple heavy and transition metals. IscR appears to be an activator to regulate genes involved in resistance to heavy or transition metal(loid)s but not for genes responsible for Se(IV) reduction.
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Affiliation(s)
| | | | | | | | | | | | | | - Gejiao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
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Pseudomonas seleniipraecipitans proteins potentially involved in selenite reduction. Curr Microbiol 2014; 69:69-74. [PMID: 24604150 DOI: 10.1007/s00284-014-0555-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 01/14/2014] [Indexed: 10/25/2022]
Abstract
Pseudomonas seleniipraecipitans grows in the presence of high levels of selenite and selenate and reduces both oxyanions to elemental selenium (Se(0)), a property that may make P. seleniipraecipitans useful as an inoculant for biobarriers designed to remove selenite or selenate from ground or surface waters. An earlier study showed that P. seleniipraecipitans nitrate reductase reduced selenate to Se(0), but failed to identify the protein(s) involved in selenite reduction. This study used ammonium sulfate precipitation, hydrophobic interaction chromatography, and native PAGE to isolate two electrophoretic gel regions, identified as bands A and B that showed selenite-reductase-activity. Proteomics was used to identify the proteins present in those regions. Glutathione reductase (GR) was detected in the A-band; based on this information, Saccharomyces cerevisiae GR, obtained from a commercial source, was evaluated and found to have selenite-reductase-activity, confirming that GR can reduce selenite to Se(0). Proteomics was also used to detect the proteins present in the B-band and thioredoxin reductase (ThxR) was detected as a B-band protein; based on this information, E. coli ThxR, obtained from a commercial source, was evaluated and found to have selenite-reductase-activity, confirming that ThxR can reduce selenite to elemental selenium. Thus, evidence presented in this study shows that S. cerevisiae GR and E. coli ThxR can reduce SeO3 (2-) to Se(0) and strongly suggests that P. seleniipraecipitans GR and ThxR can also reduce SeO3 (2-) to Se(0).
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Lampis S, Zonaro E, Bertolini C, Bernardi P, Butler CS, Vallini G. Delayed formation of zero-valent selenium nanoparticles by Bacillus mycoides SeITE01 as a consequence of selenite reduction under aerobic conditions. Microb Cell Fact 2014; 13:35. [PMID: 24606965 PMCID: PMC3975340 DOI: 10.1186/1475-2859-13-35] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 02/19/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Selenite (SeO32-) oxyanion shows severe toxicity to biota. Different bacterial strains exist that are capable of reducing SeO32- to non-toxic elemental selenium (Se0), with the formation of Se nanoparticles (SeNPs). These SeNPs might be exploited for technological applications due to their physico-chemical and biological characteristics. The present paper discusses the reduction of selenite to SeNPs by a strain of Bacillus sp., SeITE01, isolated from the rhizosphere of the Se-hyperaccumulator legume Astragalus bisulcatus. RESULTS Use of 16S rRNA and GyrB gene sequence analysis positioned SeITE01 phylogenetically close to B. mycoides. On agarized medium, this strain showed rhizoid growth whilst, in liquid cultures, it was capable of reducing 0.5 and 2.0 mM SeO32- within 12 and 24 hours, respectively. The resultant Se0 aggregated to form nanoparticles and the amount of Se0 measured was equivalent to the amount of selenium originally added as selenite to the growth medium. A delay of more than 24 hours was observed between the depletion of SeO32 and the detection of SeNPs. Nearly spherical-shaped SeNPs were mostly found in the extracellular environment whilst rarely in the cytoplasmic compartment. Size of SeNPs ranged from 50 to 400 nm in diameter, with dimensions greatly influenced by the incubation times. Different SeITE01 protein fractions were assayed for SeO32- reductase capability, revealing that enzymatic activity was mainly associated with the membrane fraction. Reduction of SeO32- was also detected in the supernatant of bacterial cultures upon NADH addition. CONCLUSIONS The selenite reducing bacterial strain SeITE01 was attributed to the species Bacillus mycoides on the basis of phenotypic and molecular traits. Under aerobic conditions, the formation of SeNPs were observed both extracellularly or intracellularly. Possible mechanisms of Se0 precipitation and SeNPs assembly are suggested. SeO32- is proposed to be enzymatically reduced to Se0 through redox reactions by proteins released from bacterial cells. Sulfhydryl groups on peptides excreted outside the cells may also react directly with selenite. Furthermore, membrane reductases and the intracellular synthesis of low molecular weight thiols such as bacillithiols may also play a role in SeO32- reduction. Formation of SeNPs seems to be the result of an Ostwald ripening mechanism.
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Affiliation(s)
- Silvia Lampis
- Department of Biotechnology, University of Verona, Strada le Grazie 15, Verona 37134, Italy.
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