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Sevak P, Pushkar B. Arsenic pollution cycle, toxicity and sustainable remediation technologies: A comprehensive review and bibliometric analysis. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 349:119504. [PMID: 37956515 DOI: 10.1016/j.jenvman.2023.119504] [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: 03/11/2023] [Revised: 10/11/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023]
Abstract
Arsenic pollution and its allied impacts on health are widely reported and have gained global attention in the last few decades. Although the natural distribution of arsenic is limited, anthropogenic activities have increased its mobility to distant locations, thereby increasing the number of people affected by arsenic pollution. Arsenic has a complex biogeochemical cycle which has a significant role in pollution. Therefore, this review paper has comprehensively analysed the biogeochemical cycle of arsenic which can dictate the occurrence of arsenic pollution. Considering the toxicity and nature of arsenic, the present work has also analysed the current status of arsenic pollution around the world. It is noted that the south of Asia, West-central Africa, west of Europe and Latin America are major hot spots of arsenic pollution. Bibliometric analysis was performed by using scopus database with specific search for keywords such as arsenic pollution, health hazards to obtain the relevant data. Scopus database was searched for the period of 20 years from year 2003-2023 and total of 1839 articles were finally selected for further analysis using VOS viewer. Bibliometric analysis of arsenic pollution and its health hazards has revealed that arsenic pollution is primarily caused by anthropogenic sources and the key sources of arsenic exposure are drinking water, sea food and agricultural produces. Arsenic pollution was found to be associated with severe health hazards such as cancer and other health issues. Thus considering the severity of the issue, few sustainable remediation technologies such as adsorption using microbes, biological waste material, nanomaterial, constructed wetland, phytoremediation and microorganism bioremediation are proposed for treating arsenic pollution. These approaches are environmentally friendly and highly sustainable, thus making them suitable for the current scenario of environmental crisis.
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Affiliation(s)
- Pooja Sevak
- Department of Biotechnology, University of Mumbai, Kalina, Santacruz (E), Mumbai, 400098, Maharashtra, India
| | - Bhupendra Pushkar
- Department of Biotechnology, University of Mumbai, Kalina, Santacruz (E), Mumbai, 400098, Maharashtra, India.
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Chung AP, Francisco R, Morais PV, Branco R. Genome mining to unravel potential metabolic pathways linked to gallium bioleaching ability of bacterial mine isolates. Front Microbiol 2022; 13:970147. [PMID: 36188007 PMCID: PMC9518604 DOI: 10.3389/fmicb.2022.970147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 08/15/2022] [Indexed: 11/13/2022] Open
Abstract
Gallium (Ga) is considered a high-tech Critical Metal, used in the manufacture of several microelectronic components containing either gallium arsenide (GaAs) or gallium nitride (GaN). The current high demand for this critical metal urges the development of effective recovery processes from secondary resources such as mine tailings or electronic recycling material. The importance of bioleaching as a biotechnological process to recover metals prompted this study, where an integrative approach combining experimental and genomic analysis was undertaken to identify potential mechanisms involved in bioleaching ability and strategies to cope with high metal(loid)s concentrations in five mine isolates. The Clusters of Orthologous Group (COG) annotation showed that the “amino acid transport and metabolism” [E] was the most predominant functional category in all genomes. In addition, the KEEG pathways analysis also showed predicted genes for the biosynthetic pathways of most amino acids, indicating that amino acids could have an important role in the Ga leaching mechanism. The presence of effective resistance mechanisms to Ga and arsenic (As) was particularly important in GaAs bioleaching batch assays, and might explain the divergence in bioleaching efficiency among the bacterial strains. Rhodanobacter sp. B2A1Ga4 and Sphingomonas sp. A2-49 with higher resistance, mainly to As, were the most efficient bioleaching strains under these conditions. In bioleaching assays using cell-free spent medium Arthrobacter silviterrae A2-55 with lower As resistance outperformed all the other stains. Overall, higher efficiency in Ga leaching was obtained in bioleaching assays using GaAs when compared to GaN.
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Caldeira JB, Chung AP, Piedade AP, Morais PV, Branco R. A DedA Family Membrane Protein in Indium Extrusion in Rhodanobacter sp. B2A1Ga4. Front Microbiol 2021; 12:772127. [PMID: 34925279 PMCID: PMC8679861 DOI: 10.3389/fmicb.2021.772127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/20/2021] [Indexed: 01/27/2023] Open
Abstract
Indium (In) is a critical metal widely used in electronic equipment, and the supply of this precious metal is a major challenge for sustainable development. The use of microorganisms for the recovery of this critical high-tech element has been considered an excellent eco-friendly strategy. The Rhodanobacter sp. B2A1Ga4 strain, highly resistant to In, was studied in order to disclose the bacterial mechanisms closely linked to the ability to cope with this metal. The mutation of the gene encoding for a DedA protein homolog, YqaA, affected drastically the In resistance and the cellular metabolic activity of strain Rhodanobacter sp. B2A1Ga4 in presence of this metal. This indicates that this protein plays an important role in its In resistance phenotype. The negative impact of In might be related to the high accumulation of the metal into the mutant cells showing In concentration up to approximately 4-fold higher than the native strain. In addition, the expression of the yqaA gene in this mutant reverted the bacterial phenotype with a significant decrease of In accumulation levels into the cells and an increase of In resistance. Membrane potential measurements showed similar values for native and mutant cells, suggesting that there was no loss of proton-motive force in the mutant cells. The results from this study suggest a potential role of this DedA family protein as a membrane transporter involved in the In efflux process. The mutant strain also has the potential to be used as a biotool in bioaccumulation strategies, for the recovery of In in biomining activities.
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Affiliation(s)
- Joana B Caldeira
- University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, Coimbra, Portugal
| | - Ana Paula Chung
- University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, Coimbra, Portugal
| | - Ana Paula Piedade
- University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Mechanical Engineering, Coimbra, Portugal
| | - Paula V Morais
- University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, Coimbra, Portugal
| | - Rita Branco
- University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, Coimbra, Portugal
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Pal S, Sengupta K. In silico analysis of phylogeny, structure, and function of arsenite oxidase from unculturable microbiome of arsenic contaminated soil. J Genet Eng Biotechnol 2021; 19:47. [PMID: 33779860 PMCID: PMC8006529 DOI: 10.1186/s43141-021-00146-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 03/12/2021] [Indexed: 11/10/2022]
Abstract
Background Arsenite oxidase (EC 1.20.2.1) is a metalloenzyme that catalyzes the oxidation of arsenite into lesser toxic arsenate. In this study, 78 amino acid sequences of arsenite oxidase from unculturable bacteria available in metagenomic data of arsenic-contaminated soil have been characterized by using standard bioinformatics tools to investigate its phylogenetic relationships, three-dimensional structure and functional parameters. Results The phylogenetic relationship of all arsenite oxidase from unculturable microorganisms was revealed their closeness to bacterial order Rhizobiales. The higher aliphatic content showed that these enzymes are thermostable and could be used for in situ bioremediation. A representative protein from each phylogenetic cluster was analysed for secondary structure arrangements which indicated the presence of α-helices (~63%), β-sheets (57–60%) and turns (13–15%). The validated 3D models suggested that these proteins are hetero-dimeric with two chains whereas alpha chain is the main catalytic subunit which binds with arsenic oxides. Three representative protein models were deposited in Protein Model Database. The query enzymes were predicted with two conserved motifs, one is Rieske 3Fe-4S and the other is molybdopterin protein. Conclusions Computational analysis of protein interactome revealed the protein partners might be involved in the whole process of arsenic detoxification by Rhizobiales. The overall report is unique to the best of our knowledge, and the importance of this study is to understand the theoretical aspects of the structure and functions of arsenite oxidase in unculturable bacteria residing in arsenic-contaminated sites. Supplementary Information The online version contains supplementary material available at 10.1186/s43141-021-00146-x.
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Affiliation(s)
- Siddhartha Pal
- National Centre for Cell Science, Ganeshkhind, Pune, 411007, India
| | - Kriti Sengupta
- Bioenergy Group, Agharkar Research Institute, Gopal Ganesh Agarkar Road, Pune, 411004, India.
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Caldeira JB, Morais PV, Branco R. Exploiting the biological response of two Serratia fonticola strains to the critical metals, gallium and indium. Sci Rep 2020; 10:20348. [PMID: 33230153 PMCID: PMC7683552 DOI: 10.1038/s41598-020-77447-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 11/10/2020] [Indexed: 12/30/2022] Open
Abstract
The use of microorganisms that allows the recovery of critical high-tech elements such as gallium (Ga) and indium (In) has been considered an excellent eco-strategy. In this perspective, it is relevant to understand the strategies of Ga and In resistant strains to cope with these critical metals. This study aimed to explore the effect of these metals on two Ga/In resistant strains and to scrutinize the biological processes behind the oxidative stress in response to exposure to these critical metals. Two strains of Serratia fonticola, A3242 and B2A1Ga1, with high resistance to Ga and In, were submitted to metal stress and their protein profiles showed an overexpressed Superoxide Dismutase (SOD) in presence of In. Results of inhibitor-protein native gel incubations identified the overexpressed enzyme as a Fe-SOD. Both strains exhibited a huge increase of oxidative stress when exposed to indium, visible by an extreme high amount of reactive oxygen species (ROS) production. The toxicity induced by indium triggered biological mechanisms of stress control namely, the decrease in reduced glutathione/total glutathione levels and an increase in the SOD activity. The effect of gallium in cells was not so boisterous, visible only by the decrease of reduced glutathione levels. Analysis of the cellular metabolic viability revealed that each strain was affected differently by the critical metals, which could be related to the distinct metal uptakes. Strain A3242 accumulated more Ga and In in comparison to strain B2A1Ga1, and showed lower metabolic activity. Understanding the biological response of the two metal resistant strains of S. fonticola to stress induced by Ga and In will tackle the current gap of information related with bacteria-critical metals interactions.
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Affiliation(s)
- Joana B Caldeira
- University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| | - Paula V Morais
- University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| | - Rita Branco
- University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal.
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Arsenic accumulation by a rhizosphere bacterial strain Ochrobactrum tritici reduces rice plant arsenic levels. World J Microbiol Biotechnol 2020; 36:23. [DOI: 10.1007/s11274-020-2800-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 01/08/2020] [Indexed: 01/26/2023]
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Yang P, Ke C, Zhao C, Kuang Q, Liu B, Xue X, Rensing C, Yang S. ArsM-mediated arsenite volatilization is limited by efflux catalyzed by As efflux transporters. CHEMOSPHERE 2020; 239:124822. [PMID: 31726527 DOI: 10.1016/j.chemosphere.2019.124822] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 09/06/2019] [Accepted: 09/09/2019] [Indexed: 06/10/2023]
Abstract
Arsenic (As) methylation is regarded as an efficient strategy for As contamination remediation by As volatilization. However, most microorganisms display low As volatilization efficiency, which is possibly linked to As efflux transporters competing for cytoplasmic As(III) as a substrate. Here, we developed two types of As biosensors in Escherichia coli to compare the As efflux rate of three efflux transporters and to further investigate the correlation between As efflux rates and As volatilization. The engineered As-sensitive E. coli AW3110 expressing arsBRP, acr3RP or arsBEC displayed a higher As resistance compared to the control. The fluorescence intensity was in a linear correlation in the range of 0-2.0 μmol/L of As(III). The intracellular As(III) concentration was negatively related to As efflux activity of As efflux transporter, which was consistent with the As resistance assays. Moreover, arsM derived from R. palustris CGA009 was subsequently introduced to construct an E. coli AW3110 co-expressing arsB/acr3 and arsM, which exhibited higher As(III) resistance, lower fluorescence intensity and intracellular As concentration compared to the engineered E. coli AW3110 expressing only arsB/acr3. The As volatilization efficiency was negatively related to As efflux activity of efflux transporters, the recombinants without arsB/acr3 displayed the highest rate of As volatilization. This study provided new insights into parameters affecting As volatilization with As efflux being the main limiting factor for As methylation and subsequent volatilization in many microorganisms.
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Affiliation(s)
- Pengmin Yang
- Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen, 361021, China
| | - Changdong Ke
- Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen, 361021, China
| | - Chungui Zhao
- Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen, 361021, China.
| | - Qingyue Kuang
- Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen, 361021, China
| | - Bixiu Liu
- Institute of Environmental Microbiology, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Ximei Xue
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 361021, China
| | - Christopher Rensing
- Institute of Environmental Microbiology, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 361021, China.
| | - Suping Yang
- Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen, 361021, China.
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Two plant-hosted whole-cell bacterial biosensors for detection of bioavailable Cr(VI). World J Microbiol Biotechnol 2019; 35:129. [DOI: 10.1007/s11274-019-2703-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 07/26/2019] [Indexed: 10/26/2022]
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Coimbra C, Branco R, Morais PV. Efficient bioaccumulation of tungsten by Escherichia coli cells expressing the Sulfitobacter dubius TupBCA system. Syst Appl Microbiol 2019; 42:126001. [PMID: 31326140 DOI: 10.1016/j.syapm.2019.126001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 07/05/2019] [Accepted: 07/09/2019] [Indexed: 01/30/2023]
Abstract
Tungsten (W) is a valuable element with considerable industrial and economic importance that belongs to the European Union list of critical metals with a high supply risk. Therefore, the development of effective and new methods for W recovery is essential to ensure a sustainable supply. In the present study, the Sulfitobacter dubius W transport system TupABC was explored in order to demonstrate both its functionality in Escherichia coli cells and to construct a bioaccumulator (EcotupW). The complete gene cluster tupBCA or partial gene cluster tupBC were cloned in an expression vector and transformed into E. coli. Metal accumulation was evaluated when each construct strain was grown with three separate metal oxyanions (tungstate, molybdate or chromate). The specificity of the bioaccumulator was determined by competition assays using cells grown with mixed solutions of metal oxyanions (W/Mo and W/Cr). The results showed the relevance of the TupA protein in the TupABC transporter system to W-uptake and also allowed Mo and Cr accumulations, although with amounts 1.7 and 2.9-fold lower than W, respectively. To identify the importance of the valine residue in the accumulation efficiency of the VTTS motif, site-directed mutagenesis of tupA was performed. A mutant with a threonine residue, instead of the respective valine, confirmed that W was internalized by nearly double the amount compared to the native form. The findings indicated that cells carrying the native S. dubius TupABC system were great W-bioaccumulators and could be promising tools for W recovery.
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Affiliation(s)
- C Coimbra
- CEMMPRE - Center of Mechanical Engineering, Materials and Processes, University of Coimbra, Coimbra, 3030-788, Portugal
| | - R Branco
- CEMMPRE - Center of Mechanical Engineering, Materials and Processes, University of Coimbra, Coimbra, 3030-788, Portugal; Department of Life Sciences, University of Coimbra, Coimbra, 3001-401, Portugal.
| | - P V Morais
- CEMMPRE - Center of Mechanical Engineering, Materials and Processes, University of Coimbra, Coimbra, 3030-788, Portugal; Department of Life Sciences, University of Coimbra, Coimbra, 3001-401, Portugal
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An endophytic Kocuria palustris strain harboring multiple arsenate reductase genes. Arch Microbiol 2019; 201:1285-1293. [DOI: 10.1007/s00203-019-01692-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 05/13/2019] [Accepted: 06/13/2019] [Indexed: 11/25/2022]
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Saba, Andreasen R, Li Y, Rehman Y, Ahmed M, Meyer R, Sabri A. Prospective role of indigenousExiguobacterium profundumPT2 in arsenic biotransformation and biosorption by planktonic cultures and biofilms. J Appl Microbiol 2018; 124:431-443. [DOI: 10.1111/jam.13636] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/10/2017] [Accepted: 11/02/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Saba
- Department of Microbiology and Molecular Genetics; University of the Punjab; Lahore Pakistan
- Interdisciplinary Nanoscience Centre; Aarhus University; Aarhus Denmark
- The Women University Multan; Multan Pakistan
| | - R. Andreasen
- Department of Geoscience; Aarhus University; Aarhus Denmark
| | - Y. Li
- Bio-Optics Institute; School of Physics and Electronics; Henan University; Henan China
| | - Y. Rehman
- Department of Microbiology and Molecular Genetics; University of the Punjab; Lahore Pakistan
| | - M. Ahmed
- Department of Microbiology and Molecular Genetics; University of the Punjab; Lahore Pakistan
| | - R.L. Meyer
- Interdisciplinary Nanoscience Centre; Aarhus University; Aarhus Denmark
| | - A.N. Sabri
- Department of Microbiology and Molecular Genetics; University of the Punjab; Lahore Pakistan
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The Arsenic Detoxification System in Corynebacteria: Basis and Application for Bioremediation and Redox Control. ADVANCES IN APPLIED MICROBIOLOGY 2017; 99:103-137. [PMID: 28438267 DOI: 10.1016/bs.aambs.2017.01.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Arsenic (As) is widespread in the environment and highly toxic. It has been released by volcanic and anthropogenic activities and causes serious health problems worldwide. To survive arsenic-rich environments, soil and saprophytic microorganisms have developed molecular detoxification mechanisms to survive arsenic-rich environments, mainly by the enzymatic conversion of inorganic arsenate (AsV) to arsenite (AsIII) by arsenate reductases, which is then extruded by arsenite permeases. One of these Gram-positive bacteria, Corynebacterium glutamicum, the workhorse of biotechnological research, is also resistant to arsenic. To sanitize contaminated soils and waters, C. glutamicum strains were modified to work as arsenic "biocontainers." Two chromosomally encoded ars operons (ars1 and ars2) are responsible for As resistance. The genes within these operons encode for metalloregulatory proteins (ArsR1/R2), arsenite permeases (Acr3-1/-2), and arsenate reductases (ArsC1/C2/C1'). ArsC1/C2 arsenate reductases are coupled to the low molecular weight thiol mycothiol (MSH) and to the recently discovered mycoredoxin-1 (Mrx-1) present in most Actinobacteria. This MSH/Mrx-1 redox system protects cells against different forms of stress, including reactive oxygen species (ROS), metals, and antibiotics. ROS can modify functional sulfur cysteines by oxidizing the thiol (-SH) to a sulfenic acid (-SOH). These oxidation-sensitive protein cysteine thiols are redox regulated by the MSH/Mrx-1 couple in Corynebacterium and Mycobacterium. In summary, the molecular mechanisms involved in arsenic resistance system in C. glutamicum have paved the way for understanding the cellular response against oxidative stress in Actinobacteria.
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Li H, Zhang L, Guo W, Xu D. Development of a genetically engineered Escherichia coli strain for plasmid transformation in Corynebacterium glutamicum. J Microbiol Methods 2016; 131:156-160. [DOI: 10.1016/j.mimet.2016.10.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 10/24/2016] [Accepted: 10/24/2016] [Indexed: 10/20/2022]
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Branco R, Sousa T, Piedade AP, Morais PV. Immobilization of Ochrobactrum tritici As5 on PTFE thin films for arsenite biofiltration. CHEMOSPHERE 2016; 146:330-337. [PMID: 26735734 DOI: 10.1016/j.chemosphere.2015.12.025] [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: 08/31/2015] [Revised: 12/01/2015] [Accepted: 12/08/2015] [Indexed: 06/05/2023]
Abstract
Ochrobactrum tritici SCII24T bacteria is an environmental strain with high capacity to resist to arsenic (As) toxicity, which makes it able to grow in the presence of As(III). The inactivation of the two functional arsenite efflux pumps, ArsB and ACR3_1, resulted in the mutant O. tritici As5 exhibiting a high accumulation of arsenite. This work describes a method for the immobilization of the mutant cells O. tritici As5, on a commercial polymeric net after sputtered modified by the deposition of poly(tetrafluoroethylene) (PTFE) thin films, and demonstrates the capacity of immobilized cells to accumulate arsenic from solutions. Six different set of deposition parameters for PTFE thin films were developed and tested in vitro regarding their ability to immobilize the bacterial cells. The surface that exhibited a mild zeta potential value, hydrophobic characteristics, the lowest surface free energy but with a high polar component and the appropriate ratio of chemical reactive groups allowed cells to proliferate and to grow as a biofilm. These immobilized cells maintained their ability to accumulate the surrounding arsenite, making it a great arsenic biofilter to be used in bioremediation processes.
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Affiliation(s)
- Rita Branco
- CEMUC - Department of Mechanical Engineering, University of Coimbra, Rua Luís Reis Santos, 3030-788 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3001-401 Coimbra, Portugal
| | - Tânia Sousa
- Department of Life Sciences, University of Coimbra, 3001-401 Coimbra, Portugal
| | - Ana P Piedade
- CEMUC - Department of Mechanical Engineering, University of Coimbra, Rua Luís Reis Santos, 3030-788 Coimbra, Portugal
| | - Paula V Morais
- CEMUC - Department of Mechanical Engineering, University of Coimbra, Rua Luís Reis Santos, 3030-788 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3001-401 Coimbra, Portugal.
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