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Li S, Li Z, Wu M, Zhou Y, Tang W, Zhong H. Mercury transformations in algae, plants, and animals: The occurrence, mechanisms, and gaps. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 911:168690. [PMID: 38000748 DOI: 10.1016/j.scitotenv.2023.168690] [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: 10/16/2023] [Revised: 11/16/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023]
Abstract
Mercury (Hg) is a global pollutant showing potent toxicity to living organisms. The transformations of Hg are critical to global Hg cycling and Hg exposure risks, considering Hg mobilities and toxicities vary depending on Hg speciation. Though currently well understood in ambient environments, Hg transformations are inadequately explored in non-microbial organisms. The primary drivers of in vivo Hg transformations are far from clear, and the impacts of these processes on global Hg cycling and Hg associated health risks are not well understood. This hinders a comprehensive understanding of global Hg cycling and the effective mitigation of Hg exposure risks. Here, we focused on Hg transformations in non-microbial organisms, particularly algae, plants, and animals. The process of Hg oxidation/reduction and methylation/demethylation in organisms were reviewed since these processes are the key transformations between the dominant Hg species, i.e., elemental Hg (Hg0), divalent inorganic Hg (IHgII), and methylmercury (MeHg). By summarizing the current knowledge of Hg transformations in organisms, we proposed the potential yet overlooked drivers of these processes, along with potential challenges that hinder a full understanding of in vivo Hg transformations. Knowledge summarized in this review would help achieve a comprehensive understanding of the fate and toxicity of Hg in organisms, providing a basis for predicting Hg cycles and mitigating human exposure.
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Affiliation(s)
- Shouying Li
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing 210023, China
| | - Zhuoran Li
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing 210023, China
| | - Mengjie Wu
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing 210023, China
| | - Yang Zhou
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing 210023, China
| | - Wenli Tang
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing 210023, China.
| | - Huan Zhong
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing 210023, China.
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Ranjbar S, Malcata FX. Is Genetic Engineering a Route to Enhance Microalgae-Mediated Bioremediation of Heavy Metal-Containing Effluents? Molecules 2022; 27:1473. [PMID: 35268582 PMCID: PMC8911655 DOI: 10.3390/molecules27051473] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 12/19/2022] Open
Abstract
Contamination of the biosphere by heavy metals has been rising, due to accelerated anthropogenic activities, and is nowadays, a matter of serious global concern. Removal of such inorganic pollutants from aquatic environments via biological processes has earned great popularity, for its cost-effectiveness and high efficiency, compared to conventional physicochemical methods. Among candidate organisms, microalgae offer several competitive advantages; phycoremediation has even been claimed as the next generation of wastewater treatment technologies. Furthermore, integration of microalgae-mediated wastewater treatment and bioenergy production adds favorably to the economic feasibility of the former process-with energy security coming along with environmental sustainability. However, poor biomass productivity under abiotic stress conditions has hindered the large-scale deployment of microalgae. Recent advances encompassing molecular tools for genome editing, together with the advent of multiomics technologies and computational approaches, have permitted the design of tailor-made microalgal cell factories, which encompass multiple beneficial traits, while circumventing those associated with the bioaccumulation of unfavorable chemicals. Previous studies unfolded several routes through which genetic engineering-mediated improvements appear feasible (encompassing sequestration/uptake capacity and specificity for heavy metals); they can be categorized as metal transportation, chelation, or biotransformation, with regulation of metal- and oxidative stress response, as well as cell surface engineering playing a crucial role therein. This review covers the state-of-the-art metal stress mitigation mechanisms prevalent in microalgae, and discusses putative and tested metabolic engineering approaches, aimed at further improvement of those biological processes. Finally, current research gaps and future prospects arising from use of transgenic microalgae for heavy metal phycoremediation are reviewed.
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Affiliation(s)
- Saeed Ranjbar
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal;
- Department of Chemical Engineering, University of Porto, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal
| | - Francisco Xavier Malcata
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal;
- Department of Chemical Engineering, University of Porto, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal
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Priyadarshanee M, Chatterjee S, Rath S, Dash HR, Das S. Cellular and genetic mechanism of bacterial mercury resistance and their role in biogeochemistry and bioremediation. JOURNAL OF HAZARDOUS MATERIALS 2022; 423:126985. [PMID: 34464861 DOI: 10.1016/j.jhazmat.2021.126985] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
Mercury (Hg) is a highly toxic element that occurs at low concentrations in nature. However, various anthropogenic and natural sources contribute around 5000 to 8000 metric tons of Hg per year, rapidly deteriorating the environmental conditions. Mercury-resistant bacteria that possess the mer operon system have the potential for Hg bioremediation through volatilization from the contaminated milieus. Thus, bacterial mer operon plays a crucial role in Hg biogeochemistry and bioremediation by converting both reactive inorganic and organic forms of Hg to relatively inert, volatile, and monoatomic forms. Both the broad-spectrum and narrow-spectrum bacteria harbor many genes of mer operon with their unique definitive functions. The presence of mer genes or proteins can regulate the fate of Hg in the biogeochemical cycle in the environment. The efficiency of Hg transformation depends upon the nature and diversity of mer genes present in mercury-resistant bacteria. Additionally, the bacterial cellular mechanism of Hg resistance involves reduced Hg uptake, extracellular sequestration, and bioaccumulation. The presence of unique physiological properties in a specific group of mercury-resistant bacteria enhances their bioremediation capabilities. Many advanced biotechnological tools also can improve the bioremediation efficiency of mercury-resistant bacteria to achieve Hg bioremediation.
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Affiliation(s)
- Monika Priyadarshanee
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India
| | - Shreosi Chatterjee
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India
| | - Sonalin Rath
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India
| | - Hirak R Dash
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India
| | - Surajit Das
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India.
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Dormatey R, Sun C, Ali K, Fiaz S, Xu D, Calderón-Urrea A, Bi Z, Zhang J, Bai J. ptxD/Phi as alternative selectable marker system for genetic transformation for bio-safety concerns: a review. PeerJ 2021; 9:e11809. [PMID: 34395075 PMCID: PMC8323600 DOI: 10.7717/peerj.11809] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 06/27/2021] [Indexed: 12/14/2022] Open
Abstract
Antibiotic and herbicide resistance genes are the most common marker genes for plant transformation to improve crop yield and food quality. However, there is public concern about the use of resistance marker genes in food crops due to the risk of potential gene flow from transgenic plants to compatible weedy relatives, leading to the possible development of “superweeds” and antibiotic resistance. Several selectable marker genes such as aph, nptII, aaC3, aadA, pat, bar, epsp and gat, which have been synthesized to generate transgenic plants by genetic transformation, have shown some limitations. These marker genes, which confer antibiotic or herbicide resistance and are introduced into crops along with economically valuable genes, have three main problems: selective agents have negative effects on plant cell proliferation and differentiation, uncertainty about the environmental effects of many selectable marker genes, and difficulty in performing recurrent transformations with the same selectable marker to pyramid desired genes. Recently, a simple, novel, and affordable method was presented for plant cells to convert non-metabolizable phosphite (Phi) to an important phosphate (Pi) for developing cells by gene expression encoding a phosphite oxidoreductase (PTXD) enzyme. The ptxD gene, in combination with a selection medium containing Phi as the sole phosphorus (P) source, can serve as an effective and efficient system for selecting transformed cells. The selection system adds nutrients to transgenic plants without potential risks to the environment. The ptxD/Phi system has been shown to be a promising transgenic selection system with several advantages in cost and safety compared to other antibiotic-based selection systems. In this review, we have summarized the development of selection markers for genetic transformation and the potential use of the ptxD/Phi scheme as an alternative selection marker system to minimize the future use of antibiotic and herbicide marker genes.
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Affiliation(s)
- Richard Dormatey
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Chao Sun
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Kazim Ali
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China.,National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Park Road, Islamabad Pakistan
| | - Sajid Fiaz
- Department of Plant Breeding and Genetics, The University of Haripur, Haripur, Pakistan
| | - Derong Xu
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Alejandro Calderón-Urrea
- Department of Biology, College of Science and Mathematics, California State University, Fresno, CA, USA
| | - Zhenzhen Bi
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Junlian Zhang
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Jiangping Bai
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
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Phytoremediation and Microorganisms-Assisted Phytoremediation of Mercury-Contaminated Soils: Challenges and Perspectives. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18052435. [PMID: 33801363 PMCID: PMC7967564 DOI: 10.3390/ijerph18052435] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/18/2021] [Accepted: 02/24/2021] [Indexed: 01/01/2023]
Abstract
Mercury (Hg) pollution is a global threat to human and environmental health because of its toxicity, mobility and long-term persistence. Although costly engineering-based technologies can be used to treat heavily Hg-contaminated areas, they are not suitable for decontaminating agricultural or extensively-polluted soils. Emerging phyto- and bioremediation strategies for decontaminating Hg-polluted soils generally involve low investment, simple operation, and in situ application, and they are less destructive for the ecosystem. Current understanding of the uptake, translocation and sequestration of Hg in plants is reviewed to highlight new avenues for exploration in phytoremediation research, and different phytoremediation strategies (phytostabilization, phytoextraction and phytovolatilization) are discussed. Research aimed at identifying suitable plant species and associated-microorganisms for use in phytoremediation of Hg-contaminated soils is also surveyed. Investigation into the potential use of transgenic plants in Hg-phytoremediation is described. Recent research on exploiting the beneficial interactions between plants and microorganisms (bacteria and fungi) that are Hg-resistant and secrete plant growth promoting compounds is reviewed. We highlight areas where more research is required into the effective use of phytoremediation on Hg-contaminated sites, and conclude that the approaches it offers provide considerable potential for the future.
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Gantait S, Mondal S. Transgenic approaches for genetic improvement in groundnut ( Arachis hypogaea L.) against major biotic and abiotic stress factors. J Genet Eng Biotechnol 2018; 16:537-544. [PMID: 30733771 PMCID: PMC6354002 DOI: 10.1016/j.jgeb.2018.08.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 07/17/2018] [Accepted: 08/29/2018] [Indexed: 01/11/2023]
Abstract
Cultivated groundnut (Arachis hypogaea L.) is considered as one of the primary oilseed crops and a major fodder for cattle industry in most of the developing countries, owing to its rich source of protein. It is due to its geocarpic nature of growth that the overall yield performance of groundnut is hindered by several biotic and abiotic stress factors. Multidimensional attempts were undertaken to combat these factors by developing superior groundnut varieties, modified with integral mechanism of tolerance/resistance; however this approach proved to be futile, owing to inferior pod and kernel quality. As a superior alternative, biotechnological intervention like transformation of foreign genes, either directly (biolistic) or via Agrobacterium, significantly aided in the development of advanced groundnut genotypes equipped with integral resistance against stresses and enhanced yield attributing traits. Several genes triggered by biotic and abiotic stresses, were detected and some of them were cloned and transformed as major parts of transgenic programmes. Application of modern molecular biological techniques, in designing biotic and abiotic stress tolerant/resistant groundnut varieties that exhibited mechanisms of resistance, relied on the expression of specific genes associated to particular stress. The genetically transformed stress tolerant groundnut varieties possess the potential to be employed as donor parents in traditional breeding programmes for developing varieties that are resilient to fungal, bacterial, and viral diseases, as well as to draught and salinity. The present review emphasizes on the retrospect and prospect of genetic transformation tools, implemented for the enhancement of groundnut varieties against key biotic and abiotic stress factors.
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Affiliation(s)
- Saikat Gantait
- All India Coordinated Research Project on Groundnut, Directorate of Research, Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal 741235, India
- Department of Genetics and Plant Breeding, Faculty of Agriculture, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal 741252, India
| | - Suvendu Mondal
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra, India
- Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, Maharashtra, India
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Naguib MM, El-Gendy AO, Khairalla AS. Microbial Diversity of Mer Operon Genes and Their Potential Rules in Mercury Bioremediation and Resistance. ACTA ACUST UNITED AC 2018. [DOI: 10.2174/1874070701812010056] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:Mercury is a toxic metal that is present in small amounts in the environment, but its level is rising steadily, due to different human activities, such as industrialization. It can reach humans through the food chain, amalgam fillings, and other sources, causing different neurological disorders, memory loss, vision impairment, and may even lead to death; making its detoxification an urgent task.Methods:Various physical and chemical mercury remediation techniques are available, which generally aim at: (i) reducing its mobility or solubility; (ii) causing its vaporization or condensation; (iii) its separation from contaminated soils. Biological remediation techniques, commonly known as bioremediation, are also another possible alternative, which is considered as cheaper than the conventional means and can be accomplished using either (i) organisms harboring themeroperon genes (merB,merA,merR,merP,merT,merD,merF,merC,merE,merHandmerG), or (ii) plants expressing metal-binding proteins. Recently, differentmerdeterminants have been genetically engineered into several organisms, including bacteria and plants, to aid in detoxification of both ionic and organic forms of mercury.Results:Bacteria that are resistant to mercury compounds have at least a mercuric reductase enzyme (MerA) that reduces Hg+2to volatile Hg0, a membrane-bound protein (MerT) for Hg+2uptake and an additional enzyme, MerB, that degrades organomercurials by protonolysis. Presence of bothmerA andmerB genes confer broad-spectrum mercury resistance. However,merA alone confers narrow spectrum inorganic mercury resistance.Conclusion:To conclude, this review discusses the importance of mercury-resistance genes in mercury bioremediation. Functional analysis ofmeroperon genes and the recent advances in genetic engineering techniques could provide the most environmental friendly, safe, effective and fantastic solution to overcome mercuric toxicity.
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Krishna G, Singh BK, Kim EK, Morya VK, Ramteke PW. Progress in genetic engineering of peanut (Arachis hypogaea L.)--a review. PLANT BIOTECHNOLOGY JOURNAL 2015; 13:147-62. [PMID: 25626474 DOI: 10.1111/pbi.12339] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 11/27/2014] [Accepted: 12/17/2014] [Indexed: 05/20/2023]
Abstract
Peanut (Arachis hypogaea L.) is a major species of the family, Leguminosae, and economically important not only for vegetable oil but as a source of proteins, minerals and vitamins. It is widely grown in the semi-arid tropics and plays a role in the world agricultural economy. Peanut production and productivity is constrained by several biotic (insect pests and diseases) and abiotic (drought, salinity, water logging and temperature aberrations) stresses, as a result of which crop experiences serious economic losses. Genetic engineering techniques such as Agrobacterium tumefaciens and DNA-bombardment-mediated transformation are used as powerful tools to complement conventional breeding and expedite peanut improvement by the introduction of agronomically useful traits in high-yield background. Resistance to several fungal, virus and insect pest have been achieved through variety of approaches ranging from gene coding for cell wall component, pathogenesis-related proteins, oxalate oxidase, bacterial chloroperoxidase, coat proteins, RNA interference, crystal proteins etc. To develop transgenic plants withstanding major abiotic stresses, genes coding transcription factors for drought and salinity, cytokinin biosynthesis, nucleic acid processing, ion antiporter and human antiapoptotic have been used. Moreover, peanut has also been used in vaccine production for the control of several animal diseases. In addition to above, this study also presents a comprehensive account on the influence of some important factors on peanut genetic engineering. Future research thrusts not only suggest the use of different approaches for higher expression of transgene(s) but also provide a way forward for the improvement of crops.
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Affiliation(s)
- Gaurav Krishna
- Jacob School of Biotechnology & Bioengineering, Sam Higginbottom Institute of Agriculture, Technology & Sciences (Formerly Allahabad Agricultural Institute), Deemed University, Allahabad, Uttar Pradesh, India
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Chu Y, Guimarães LA, Wu CL, Timper P, Holbrook CC, Ozias-Akins P. A Technique to Study Meloidogyne arenaria Resistance in Agrobacterium rhizogenes-Transformed Peanut. PLANT DISEASE 2014; 98:1292-1299. [PMID: 30703931 DOI: 10.1094/pdis-12-13-1241-re] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A reliable peanut root transformation system would be useful to study the functions of genes involved in root biology and disease resistance. The objective of this study was to establish an effective protocol to produce composite plants mediated by Agrobacterium rhizogenes transformation. In total, 75% of transformed peanut seedlings produced an average of 2.83 transgenic roots per plant. Peanut seed had the highest germination rate after treatment in a chlorine gas chamber for 8 h compared with 16 h in chlorine gas or Clorox and mercuric chloride immersion treatments. High transformation efficiency was achieved when the wound site for A. rhizogenes inoculation was covered with vermiculite instead of enclosing the whole plant in a high humidity chamber. On average, 2.5 galls from Meloidogyne arenaria infection were formed per transgenic root from susceptible genotype TifGP-2. These data indicate that A. rhizogenes-transformed roots can be used to phenotype the host response to nematode challenge. Transformation of RLP-2, a candidate resistance gene for M. arenaria integrated into a silencing construct, did not alter the resistance response of Tifguard, even though downregulation of endogenous RLP-2 expression was detected in transformed roots. It is likely that RLP-2 is not the gene conditioning M. arenaria resistance in peanut.
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Affiliation(s)
- Y Chu
- Department of Horticulture, The University of Georgia Tifton Campus, Tifton 31793-5766
| | - L A Guimarães
- Department of Horticulture, The University of Georgia Tifton Campus, Tifton 31793-5766
| | - C L Wu
- Department of Horticulture, The University of Georgia Tifton Campus, Tifton 31793-5766
| | - P Timper
- United States Department of Agriculture-Agricultural Research Service, Tifton, GA 31793; and
| | - C C Holbrook
- United States Department of Agriculture-Agricultural Research Service, Tifton, GA 31793; and
| | - P Ozias-Akins
- Department of Horticulture, The University of Georgia Tifton Campus
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Pant D, Singh P. Pollution due to hazardous glass waste. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:2414-36. [PMID: 24281678 DOI: 10.1007/s11356-013-2337-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Accepted: 11/04/2013] [Indexed: 05/16/2023]
Abstract
Pollution resulting from hazardous glass (HG) is widespread across the globe, both in terms of quantity and associated health risks. In waste cathode ray tube (CRT) and fluorescent lamp glass, mercury and lead are present as the major pollutants. The current review discusses the issues related to quantity and associated risk from the pollutant present in HG and proposes the chemical, biological, thermal, hybrid, and nanotechniques for its management. The hybrid is one of the upcoming research models involving the compatible combination of two or more techniques for better and efficient remediation. Thermal mercury desorption starts at 100 °C but for efficient removal, the temperature should be >460 °C. Involvement of solar energy for this purpose makes the research more viable and ecofriendly. Nanoparticles such as Fe, Se, Cu, Ni, Zn, Ag, and WS2 alone or with its formulation can immobilize heavy metals present in HG by involving a redox mechanism. Straight-line equation from year-wise sale can provide future sale data in comparison with lifespan which gives future pollutant approximation. Waste compact fluorescent lamps units projected for the year 2015 is 9,300,000,000 units and can emit nearly 9,300 kg of mercury. On the other hand, CRT monitors have been continuously replaced by more improved versions like liquid crystal display and plasma display panel resulting in the production of more waste. Worldwide CRT production was 83,300,000 units in 2002 and can approximately release 83,000 metric tons of lead.
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Affiliation(s)
- Deepak Pant
- Department of Environmental Sciences, Central University of Himachal Pradesh, Dharamshala, Himachal Pradesh, 176215, India,
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Chatterjee S, Mitra A, Datta S, Veer V. Phytoremediation Protocols: An Overview. SOIL BIOLOGY 2013. [DOI: 10.1007/978-3-642-35564-6_1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Atif RM, Patat-Ochatt EM, Svabova L, Ondrej V, Klenoticova H, Jacas L, Griga M, Ochatt SJ. Gene Transfer in Legumes. PROGRESS IN BOTANY 2013. [DOI: 10.1007/978-3-642-30967-0_2] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Transgenic Approaches to Enhance Phytoremediation of Heavy Metal-Polluted Soils. SOIL BIOLOGY 2013. [DOI: 10.1007/978-3-642-35564-6_12] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Wang J, Feng X, Anderson CWN, Xing Y, Shang L. Remediation of mercury contaminated sites - A review. JOURNAL OF HAZARDOUS MATERIALS 2012; 221-222:1-18. [PMID: 22579459 DOI: 10.1016/j.jhazmat.2012.04.035] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 04/08/2012] [Accepted: 04/14/2012] [Indexed: 05/08/2023]
Abstract
Environmental contamination caused by mercury is a serious problem worldwide. Coal combustion, mercury and gold mining activities and industrial activities have led to an increase in the mercury concentration in soil. The objective of this paper is to present an up-to-date understanding of the available techniques for the remediation of soil contaminated with mercury through considering: mercury contamination in soil, mercury speciation in soil; mercury toxicity to humans, plants and microorganisms, and remediation options. This paper describes the commonly employed and emerging techniques for mercury remediation, namely: stabilization/solidification (S/S), immobilization, vitrification, thermal desorption, nanotechnology, soil washing, electro-remediation, phytostabilization, phytoextraction and phytovolatilization.
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Affiliation(s)
- Jianxu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002, China
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Over expression of rice chitinase gene in transgenic peanut (Arachis hypogaea L.) improves resistance against leaf spot. Mol Biotechnol 2012; 50:129-36. [PMID: 21688039 DOI: 10.1007/s12033-011-9426-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A Rice chitinase-3 under enhance version of CaMV 35S was introduced into peanut (Arachis hypogaea L.) through Agrobacterium mediation. Agrobacterium tumefaciens strain LB4404 was used harboring the binary vector (pB1333-EN4-RCG3) containing the chitinase (chit) and hygromycin resistance (hpt) gene as selectable marker. Putative transgenic shoots were regenerated and grown on MS medium supplemented with 5 mg/l BAP, 1 mg/l kinetin, and 30 mg/l hygromycin. Elongated shoots were examined for the presence of the integrated rice chitinase gene along with hygromycin gene as selectable. The integration pattern of transgene in the nuclear genome of the putative transformed plants (T(0)) was confirmed through Southern hybridization analysis of the genomic DNA. Survival rate of the in vitro regenerated plantlets was over 60% while healthy putatively transgenic (T(0)) plants with over 42% transformation frequency were produced through Agrobacterium mediated gene transfer of the rice chitinase gene and all the plants flowered and set seed normally. T1 plants were tested for resistance against Cercospora arachidicola by infection with the microspores. Transgenic strains exhibited a higher resistance than the control (non-transgenic plants). chitinase gene expression in highly resistant transgenic strains was compared to that of a susceptible control. A good correlation was observed between chitinase activity and fungal pathogen resistance.
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Genetically modified plants in phytoremediation of heavy metal and metalloid soil and sediment pollution. Biotechnol Adv 2009; 27:799-810. [DOI: 10.1016/j.biotechadv.2009.06.003] [Citation(s) in RCA: 194] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Revised: 06/16/2009] [Accepted: 06/20/2009] [Indexed: 11/22/2022]
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Genetic engineering to enhance mercury phytoremediation. Curr Opin Biotechnol 2009; 20:213-9. [PMID: 19328673 DOI: 10.1016/j.copbio.2009.02.010] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2008] [Revised: 02/17/2009] [Accepted: 02/20/2009] [Indexed: 11/21/2022]
Abstract
Most phytoremediation studies utilize merA or merB genes to modify plants via the nuclear or chloroplast genome, expressing organomercurial lyase and/or mercuric ion reductase in the cytoplasm, endoplasmic reticulum or within plastids. Several plant species including Arabidopsis, tobacco, poplar, rice, Eastern cottonwood, peanut, salt marsh grass and Chlorella have been transformed with these genes. Transgenic plants grew exceedingly well in soil contaminated with organic (approximately 400 microM PMA) or inorganic mercury (approximately 500 microM HgCl(2)), accumulating Hg in roots surpassing the concentration in soil (approximately 2000 microg/g). However, none of these plants were tested in the field to demonstrate real potential of this approach. Availability of metal transporters, translocators, chelators and the ability to express membrane proteins could further enhance mercury phytoremediation capabilities.
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Chu Y, Deng XY, Faustinelli P, Ozias-Akins P. Bcl-xL transformed peanut (Arachis hypogaea L.) exhibits paraquat tolerance. PLANT CELL REPORTS 2008; 27:85-92. [PMID: 17891400 DOI: 10.1007/s00299-007-0444-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2007] [Revised: 08/07/2007] [Accepted: 09/03/2007] [Indexed: 05/17/2023]
Abstract
The human Bcl-xL gene was transformed into peanut cultivar Georgia Green via microprojectile bombardment. Following selection on hygromycin-containing medium and regeneration, eighty hygromycin-resistant callus clusters were recovered. Southern blot analysis of ten fertile lines revealed multiple insertions of the Bcl-xL transgene in most lines. Western blot analysis of primary plants and T1 progenies demonstrated detectable levels of Bcl-xL expression in four transgenic lines. We could not detect Bcl-xL protein in other tested lines even though transcripts were identified by RT-PCR and northern blot. Three of the western-positive transgenic lines either were sterile or the progenies lost the expressive copy of Bcl-xL. Only T1 progenies from line BX25-4-2a-19 continued to express an intermediate level of Bcl-xL. This line demonstrated paraquat tolerance at the 5 microM level. Tolerance to salt of T1 and T2 seeds from seven other transgenic lines also was tested, but no tolerance was found in these lines. A high level of Bcl-xL transgene expression may be deleterious to plant growth and development even though the gene may confer tolerance to other abiotic and biotic stresses such as drought and pathogens.
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Affiliation(s)
- Y Chu
- Department of Horticulture, The University of Georgia, Tifton, GA, 31973-0748, USA
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Allen GC, Flores-Vergara MA, Krasynanski S, Kumar S, Thompson WF. A modified protocol for rapid DNA isolation from plant tissues using cetyltrimethylammonium bromide. Nat Protoc 2007; 1:2320-5. [PMID: 17406474 DOI: 10.1038/nprot.2006.384] [Citation(s) in RCA: 596] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We describe a modification of the DNA extraction method, in which cetyltrimethylammonium bromide (CTAB) is used to extract nucleic acids from plant tissues. In contrast to the original method, the modified CTAB procedure is faster, omits the selective precipitation and CsCl gradient steps, uses less expensive and toxic reagents, requires only inexpensive laboratory equipment and is more readily adapted to high-throughput DNA extraction. This protocol yields approximately 5-30 microg of total DNA from 200 mg of tissue fresh weight, depending on plant species and tissue source. It can be completed in as little as 5-6 h.
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Affiliation(s)
- G C Allen
- Department of Horticultural Science and Crop Science, 1200 Partners II, Campus Box 7550, 840 Main Campus Drive, North Carolina State University, Raleigh, NC 27606-7550, USA.
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Proite K, Leal-Bertioli SCM, Bertioli DJ, Moretzsohn MC, da Silva FR, Martins NF, Guimarães PM. ESTs from a wild Arachis species for gene discovery and marker development. BMC PLANT BIOLOGY 2007; 7:7. [PMID: 17302987 PMCID: PMC1808460 DOI: 10.1186/1471-2229-7-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Accepted: 02/15/2007] [Indexed: 05/14/2023]
Abstract
BACKGROUND Due to its origin, peanut has a very narrow genetic background. Wild relatives can be a source of genetic variability for cultivated peanut. In this study, the transcriptome of the wild species Arachis stenosperma accession V10309 was analyzed. RESULTS ESTs were produced from four cDNA libraries of RNAs extracted from leaves and roots of A. stenosperma. Randomly selected cDNA clones were sequenced to generate 8,785 ESTs, of which 6,264 (71.3%) had high quality, with 3,500 clusters: 963 contigs and 2537 singlets. Only 55.9% matched homologous sequences of known genes. ESTs were classified into 23 different categories according to putative protein functions. Numerous sequences related to disease resistance, drought tolerance and human health were identified. Two hundred and six microsatellites were found and markers have been developed for 188 of these. The microsatellite profile was analyzed and compared to other transcribed and genomic sequence data. CONCLUSION This is, to date, the first report on the analysis of transcriptome of a wild relative of peanut. The ESTs produced in this study are a valuable resource for gene discovery, the characterization of new wild alleles, and for marker development. The ESTs were released in the [GenBank:EH041934 to EH048197].
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Affiliation(s)
- Karina Proite
- Departamento de Biologia Celular, Universidade de Brasília, Campus I, Brasília, DF. Brazil
- EMBRAPA Recursos Genéticos e Biotecnologia. Parque Estação Biológica, CP 02372. Final W5 Norte, Brasília, DF. Brazil
| | - Soraya CM Leal-Bertioli
- EMBRAPA Recursos Genéticos e Biotecnologia. Parque Estação Biológica, CP 02372. Final W5 Norte, Brasília, DF. Brazil
| | - David J Bertioli
- Universidade Católica de Brasília, Pós Graduação Campus II, SGAN 916, Brasília, DF. Brazil
| | - Márcio C Moretzsohn
- EMBRAPA Recursos Genéticos e Biotecnologia. Parque Estação Biológica, CP 02372. Final W5 Norte, Brasília, DF. Brazil
| | - Felipe R da Silva
- EMBRAPA Recursos Genéticos e Biotecnologia. Parque Estação Biológica, CP 02372. Final W5 Norte, Brasília, DF. Brazil
| | | | - Patrícia M Guimarães
- EMBRAPA Recursos Genéticos e Biotecnologia. Parque Estação Biológica, CP 02372. Final W5 Norte, Brasília, DF. Brazil
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