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Zeng X, Luo G, Fan Z, Xiao Z, Lu Y, Xiao Q, Hou Z, Tang Q, Zhou Y. Whole genome identification, molecular docking and expression analysis of enzymes involved in the selenomethionine cycle in Cardamine hupingshanensis. BMC PLANT BIOLOGY 2024; 24:199. [PMID: 38500044 PMCID: PMC10949594 DOI: 10.1186/s12870-024-04898-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 03/10/2024] [Indexed: 03/20/2024]
Abstract
BACKGROUND The selenomethionine cycle (SeMTC) is a crucial pathway for the metabolism of selenium. The basic bioinformatics and functions of four enzymes involved in the cycle including S-adenosyl-methionine synthase (MAT), SAM-dependent methyltransferase (MTase), S-adenosyl-homocysteine hydrolase (SAHH) and methionine synthase (MTR), have been extensively reported in many eukaryotes. The identification and functional analyses of SeMTC genes/proteins in Cardamine hupingshanensis and their response to selenium stress have not yet been reported. RESULTS In this study, 45 genes involved in SeMTC were identified in the C. hupingshanensis genome. Phylogenetic analysis showed that seven genes from ChMAT were clustered into four branches, twenty-seven genes from ChCOMT were clustered into two branches, four genes from ChSAHH were clustered into two branches, and seven genes from ChMTR were clustered into three branches. These genes were resided on 16 chromosomes. Gene structure and homologous protein modeling analysis illustrated that proteins in the same family are relatively conserved and have similar functions. Molecular docking showed that the affinity of SeMTC enzymes for selenium metabolites was higher than that for sulfur metabolites. The key active site residues identified for ChMAT were Ala269 and Lys273, while Leu221/231 and Gly207/249 were determined as the crucial residues for ChCOMT. For ChSAHH, the essential active site residues were found to be Asn87, Asp139 and Thr206/207/208/325. Ile204, Ser111/329/377, Asp70/206/254, and His329/332/380 were identified as the critical active site residues for ChMTR. In addition, the results of the expression levels of four enzymes under selenium stress revealed that ChMAT3-1 genes were upregulated approximately 18-fold, ChCOMT9-1 was upregulated approximately 38.7-fold, ChSAHH1-2 was upregulated approximately 11.6-fold, and ChMTR3-2 genes were upregulated approximately 28-fold. These verified that SeMTC enzymes were involved in response to selenium stress to varying degrees. CONCLUSIONS The results of this research are instrumental for further functional investigation of SeMTC in C. hupingshanensis. This also lays a solid foundation for deeper investigations into the physiological and biochemical mechanisms underlying selenium metabolism in plants.
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Affiliation(s)
- Xixi Zeng
- Hubei Key Laboratory of Biological Resources Protection and Utilization, Enshi, China, Enshi
- Hubei Key Laboratory of Selenium Resource Research and Biological Application, Enshi, China, 44500
- College of Forestry and Horticulture, Hubei Minzu University, Enshi, China, 44500
| | - Guoqiang Luo
- College of Biological and Food Engineering, Hubei Minzu University, Enshi, China, 44500
| | - Zhucheng Fan
- College of Biological and Food Engineering, Hubei Minzu University, Enshi, China, 44500
| | - Zhijing Xiao
- Hubei Key Laboratory of Biological Resources Protection and Utilization, Enshi, China, Enshi
- College of Biological and Food Engineering, Hubei Minzu University, Enshi, China, 44500
| | - Yanke Lu
- Hubei Key Laboratory of Biological Resources Protection and Utilization, Enshi, China, Enshi
| | - Qiang Xiao
- College of Forestry and Horticulture, Hubei Minzu University, Enshi, China, 44500
| | - Zhi Hou
- College of Biological and Food Engineering, Hubei Minzu University, Enshi, China, 44500
| | - Qiaoyu Tang
- Hubei Key Laboratory of Biological Resources Protection and Utilization, Enshi, China, Enshi.
- College of Forestry and Horticulture, Hubei Minzu University, Enshi, China, 44500.
- Hubei Engineering Research Center of Selenium Food Nutrition and Health Intelligent Technology, Enshi, China, 44500.
| | - Yifeng Zhou
- Hubei Key Laboratory of Selenium Resource Research and Biological Application, Enshi, China, 44500.
- College of Biological and Food Engineering, Hubei Minzu University, Enshi, China, 44500.
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van der Ent A, Salinitro M, Brueckner D, Spiers KM, Montanari S, Tassoni A, Schiavon M. Differences and similarities in selenium biopathways in Astragalus, Neptunia (Fabaceae) and Stanleya (Brassicaceae) hyperaccumulators. ANNALS OF BOTANY 2023; 132:349-361. [PMID: 37602676 PMCID: PMC10583200 DOI: 10.1093/aob/mcad110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 08/17/2023] [Indexed: 08/22/2023]
Abstract
BACKGROUND AND AIMS Selenium hyperaccumulator species are of primary interest for studying the evolution of hyperaccumulation and for use in biofortification because selenium is an essential element in human nutrition. In this study, we aimed to determine whether the distributions of selenium in the three most studied hyperaccumulating taxa (Astragalus bisulcatus, Stanleya pinnata and Neptunia amplexicaulis) are similar or contrasting, in order to infer the underlying physiological mechanisms. METHODS This study used synchrotron-based micro-X-ray fluorescence (µXRF) techniques to visualize the distribution of selenium and other elements in fresh hydrated plant tissues of A. racemosus, S. pinnata and N. amplexicaulis. KEY RESULTS Selenium distribution differed widely in the three species: in the leaves of A. racemosus and N. amplexicaulis selenium was mainly concentrated in the pulvini, whereas in S. pinnata it was primarilylocalized in the leaf margins. In the roots and stems of all three species, selenium was absent in xylem cells, whereas it was particularly concentrated in the pith rays of S. pinnata and in the phloem cells of A. racemosus and N. amplexicaulis. CONCLUSIONS This study shows that Astragalus, Stanleya and Neptunia have different selenium-handling physiologies, with different mechanisms for translocation and storage of excess selenium. Important dissimilarities among the three analysed species suggest that selenium hyperaccumulation has probably evolved multiple times over under similar environmental pressures in the US and Australia.
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Affiliation(s)
- Antony van der Ent
- Laboratory of Genetics, Wageningen University and Research, Wageningen, The Netherlands
- Centre for Mined Land Rehabilitation, Sustainable Minerals Institute, The University of Queensland, Brisbane, Queensland, Australia
- Université de Lorraine, INRAE, LSE, F-54000 Nancy, France
| | - Mirko Salinitro
- Department of Biological Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | | | | | - Sofia Montanari
- Department of Biological Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Annalisa Tassoni
- Department of Biological Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Michela Schiavon
- Department of Agricultural, Forest and Food Sciences (DISAFA), University of Turin, Turin, Italy
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Szőllősi R, Molnár Á, Janovszky P, Kéri A, Galbács G, Dernovics M, Kolbert Z. Selenate triggers diverse oxidative responses in Astragalus species with diverse selenium tolerance and hyperaccumulation capacity. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 202:107976. [PMID: 37625253 DOI: 10.1016/j.plaphy.2023.107976] [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: 06/14/2023] [Revised: 08/08/2023] [Accepted: 08/16/2023] [Indexed: 08/27/2023]
Abstract
Selenium (Se) hyperaccumulators are capable of uptake and tolerate high Se dosages. Excess Se-induced oxidative responses were compared in Astragalus bisulcatus and Astragalus cicer. Plants were grown on media supplemented with 0, 25 or 75 μM selenate for 14 days. Both A. bisulcatus and A. cicer accumulated >2000 μg/g dry weight Se to the shoot but the translocation factors of A. cicer were below 1 suggesting its non hyperaccumulator nature. A. cicer showed Se sensitivity indicated by reduced seedling fresh weight, root growth and root apical meristem viability, altered element homeostasis in the presence of Se. In Se-exposed A. bisulcatus, less toxic organic Se forms (mainly MetSeCys, γ-Glu-MetSeCys, and a selenosugar) dominated, while these were absent from A. cicer suggesting that the majority of the accumulated Se may be present as inorganic forms. The glutathione-dependent processes were more affected, while ascorbate levels were not notably influenced by Se in either species. Exogenous Se triggered more intense accumulation of malondialdehyde in the sensitive A. cicer compared with the tolerant A. bisulcatus. The extent of protein carbonylation in the roots of the 75 μM Se-exposed A. cicer exceeded that of A. bisulcatus indicating a correlation between selenate sensitivity and the degree of protein carbonylation. Overall, our results reveal connection between oxidative processes and Se sensitivity/tolerance/hyperaccumulation and contribute to the understanding of the molecular responses to excess Se.
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Affiliation(s)
- Réka Szőllősi
- Department of Plant Biology, University of Szeged, Közép alley 52, 6726, Szeged, Hungary
| | - Árpád Molnár
- Department of Plant Biology, University of Szeged, Közép alley 52, 6726, Szeged, Hungary
| | - Patrick Janovszky
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm square 7, 6720, Szeged, Hungary
| | - Albert Kéri
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm square 7, 6720, Szeged, Hungary
| | - Gábor Galbács
- Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm square 7, 6720, Szeged, Hungary
| | - Mihály Dernovics
- Department of Plant Physiology, Agricultural Institute, Centre for Agricultural Research, Eötvös Loránd Research Network, Brunszvik str. 2., 2462, Martonvásár, Hungary
| | - Zsuzsanna Kolbert
- Department of Plant Biology, University of Szeged, Közép alley 52, 6726, Szeged, Hungary.
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Montanari S, Salinitro M, Simoni A, Ciavatta C, Tassoni A. Foraging for selenium: a comparison between hyperaccumulator and non-accumulator plant species. Sci Rep 2023; 13:10661. [PMID: 37391494 PMCID: PMC10313833 DOI: 10.1038/s41598-023-37249-z] [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: 04/26/2023] [Accepted: 06/19/2023] [Indexed: 07/02/2023] Open
Abstract
Selenium (Se) hyperaccumulators are a unique group of plants that can accumulate this element in their aerial parts at concentrations exceeding 100 mg kgDW-1. These plants actively search for Se in the soil, a phenomenon known as root foraging, reported to date only by few studies. In this study, the effect of localized Se enrichment, in the form of selenite and selenate, was investigated on the root architecture of two Se-hyperaccumulators (Stanleya pinnata and Astragalus bisulcatus) and two non-accumulators (Brassica juncea and Medicago sativa). Rhizoboxes were divided into two halves: one half was filled with control soil while the other with selenate or selenite (30 mg kgDW-1) spiked soil. Seedling were transferred into the interface of the two soils and allowed to grow for three weeks under controlled light and temperature conditions. Staneya pinnata exhibited equal root density in both halves of the rhizobox when grown in control/control and selenite/control soil treatments. However, in the presence of selenate, S. pinnata developed 76% of the roots towards the selenate-enriched half, indicating an active root foraging. In contrast, A. bisulcatus and the non-accumulators B. juncea and M. sativa did not show any preferential distribution of roots. This study revealed that only S. pinnata showed the ability to detect and forage for Se when provided as selenate. Non-accumulators did not show any morphological or Se-accumulation difference associated with the presence of Se in soil in either form.
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Affiliation(s)
- Sofia Montanari
- Department of Biological Geological and Environmental Sciences, University of Bologna, Via Irnerio 42, 40126, Bologna, Italy
| | - Mirko Salinitro
- Department of Biological Geological and Environmental Sciences, University of Bologna, Via Irnerio 42, 40126, Bologna, Italy.
| | - Andrea Simoni
- Department of Agricultural and Food Sciences, University of Bologna, Viale Giuseppe Fanin 40, 40127, Bologna, Italy
| | - Claudio Ciavatta
- Department of Agricultural and Food Sciences, University of Bologna, Viale Giuseppe Fanin 40, 40127, Bologna, Italy
- Centro Interdipartimentale di Ricerca Industriale sull'Agroalimentare, University of Bologna, Via Quinto Bucci 336, 47521, Cesena, Italy
| | - Annalisa Tassoni
- Department of Biological Geological and Environmental Sciences, University of Bologna, Via Irnerio 42, 40126, Bologna, Italy
- Centro Interdipartimentale di Ricerca Industriale sull'Agroalimentare, University of Bologna, Via Quinto Bucci 336, 47521, Cesena, Italy
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Subirana MA, Boada R, Xiao T, Llugany M, Valiente M. Direct and indirect selenium speciation in biofortified wheat: A tale of two techniques. PHYSIOLOGIA PLANTARUM 2023; 175:e13843. [PMID: 36538026 PMCID: PMC10107779 DOI: 10.1111/ppl.13843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 11/26/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Wheat can be biofortified with different inorganic selenium (Se) forms, selenite or selenate. The choice of Se source influences the physiological response of the plant and the Se metabolites produced. We looked at selenium uptake, distribution and metabolization in wheat exposed to selenite, selenate and a 1:1 molar mixture of both to determine the impact of each treatment on the Se speciation in roots, shoots, and grains. To achieve a comprehensive quantification of the Se species, the complementarity of high-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry and X-ray absorption spectroscopy was exploited. This approach allowed the identification of the six main selenium species: selenomethionine, selenocysteine, selenocystine, selenite, selenate, and elemental selenium. The three treatments resulted in similar total selenium concentration in grains, 90-150 mg Se kg-1 , but produced different effects in the plant. Selenite enhanced root accumulation (66% of selenium) and induced the maximum toxicity, whereas selenate favored shoot translocation (46%). With the 1:1 mixture, selenium was distributed along the plant generating lower toxicity. Although all conditions resulted in >92% of organic selenium in the grain, selenate produced mainly C-Se-C forms, such as selenomethionine, while selenite (alone or in the mixture) enhanced the production of C-Se-Se-C forms, such as selenocystine, modifying the selenoamino acid composition. These results provide a better understanding of the metabolization of selenium species which is key to minimize plant toxicity and any concomitant effect that may arise due to Se-biofortification.
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Affiliation(s)
- Maria Angels Subirana
- GTS‐UAB Research Group, Department of Chemistry, Faculty of ScienceUniversitat Autònoma de BarcelonaBellaterraSpain
| | - Roberto Boada
- GTS‐UAB Research Group, Department of Chemistry, Faculty of ScienceUniversitat Autònoma de BarcelonaBellaterraSpain
| | - Tingting Xiao
- GTS‐UAB Research Group, Department of Chemistry, Faculty of ScienceUniversitat Autònoma de BarcelonaBellaterraSpain
| | - Mercè Llugany
- Plant Physiology Group (BABVE), Facultat de BiociènciesUniversitat Autònoma de BarcelonaBellaterraSpain
| | - Manuel Valiente
- GTS‐UAB Research Group, Department of Chemistry, Faculty of ScienceUniversitat Autònoma de BarcelonaBellaterraSpain
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Pinto Irish K, Harvey MA, Harris HH, Aarts MGM, Chan CX, Erskine PD, van der Ent A. Micro-analytical and molecular approaches for understanding the distribution, biochemistry, and molecular biology of selenium in (hyperaccumulator) plants. PLANTA 2022; 257:2. [PMID: 36416988 PMCID: PMC9684236 DOI: 10.1007/s00425-022-04017-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 10/22/2022] [Indexed: 06/16/2023]
Abstract
Micro-analytical techniques to untangle Se distribution and chemical speciation in plants coupled with molecular biology analysis enable the deciphering of metabolic pathways responsible for Se tolerance and accumulation. Selenium (Se) is not essential for plants and is toxic at high concentrations. However, Se hyperaccumulator plants have evolved strategies to both tolerate and accumulate > 1000 µg Se g-1 DW in their living above-ground tissues. Given the complexity of the biochemistry of Se, various approaches have been adopted to study Se metabolism in plants. These include X-ray-based techniques for assessing distribution and chemical speciation of Se, and molecular biology techniques to identify genes implicated in Se uptake, transport, and assimilation. This review presents these techniques, synthesises the current state of knowledge on Se metabolism in plants, and highlights future directions for research into Se (hyper)accumulation and tolerance. We conclude that powerful insights may be gained from coupling information on the distribution and chemical speciation of Se to genome-scale studies to identify gene functions and molecular mechanisms that underpin Se tolerance and accumulation in these ecologically and biotechnologically important plants species. The study of Se metabolism is challenging and is a useful testbed for developing novel analytical approaches that are potentially more widely applicable to the study of the regulation of a wide range of metal(loid)s in hyperaccumulator plants.
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Affiliation(s)
- Katherine Pinto Irish
- The University of Queensland, Sustainable Minerals Institute, Centre for Mined Land Rehabilitation, Brisbane, QLD, 4072, Australia
| | - Maggie-Anne Harvey
- The University of Queensland, Sustainable Minerals Institute, Centre for Mined Land Rehabilitation, Brisbane, QLD, 4072, Australia
| | - Hugh H Harris
- Department of Chemistry, The University of Adelaide, Adelaide, SA, Australia
| | - Mark G M Aarts
- Laboratory of Genetics, Wageningen University and Research, Wageningen, The Netherlands
| | - Cheong Xin Chan
- The University of Queensland, School of Chemistry and Molecular Biosciences, Australian Centre for Ecogenomics, Brisbane, QLD, 4072, Australia
| | - Peter D Erskine
- The University of Queensland, Sustainable Minerals Institute, Centre for Mined Land Rehabilitation, Brisbane, QLD, 4072, Australia
| | - Antony van der Ent
- The University of Queensland, Sustainable Minerals Institute, Centre for Mined Land Rehabilitation, Brisbane, QLD, 4072, Australia.
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Cunha MLO, Oliveira LCAD, Silva VM, Montanha GS, Reis ARD. Selenium increases photosynthetic capacity, daidzein biosynthesis, nodulation and yield of peanuts plants (Arachis hypogaea L.). PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 190:231-239. [PMID: 36137309 DOI: 10.1016/j.plaphy.2022.08.006] [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: 06/13/2022] [Revised: 08/04/2022] [Accepted: 08/11/2022] [Indexed: 06/16/2023]
Abstract
This study aimed to investigate the roles of selenium (Se) application on the profile of photosynthetic pigments, oxidant metabolism, flavonoids biosynthesis, nodulation, and its relation to agronomic traits of peanut plants. Two independent experiments were carried out: one conducted in soil and the other in a nutrient solution. When the plants reached the V2 growth stage, five Se doses (0, 7.5, 15, 30, and 45 μg kg-1) and four Se concentrations (0, 5, 10, and 15 μmol L-1) were supplied as sodium selenate. The concentration of photosynthetic pigments, activity of antioxidant enzymes and the concentration of total sugars in peanut leaves increased in response to Se fertilization. In addition, Se improves nitrogen assimilation efficiency by increasing nitrate reductase activity which results in a higher concentration of ureides, amino acids and proteins. Se increases the synthesis of daidzein and genistein in the root, resulting in a greater number of nodules and concentration and transport of ureides to the leaves. Se-treated plants showed greater growth, biomass accumulation in shoots and roots, yield and Se concentration in leaves and grains. Our results contribute to food security and also to increase knowledge about the effects of Se on physiology, biochemistry and biological nitrogen fixation in legume plants.
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Affiliation(s)
- Matheus Luís Oliveira Cunha
- São Paulo State University, Faculty of Agricultural and Veterinary Sciences, Via de Acesso Prof. Paulo Donato Castellane, 14884-900, Jaboticabal, São Paulo, Brazil
| | - Lara Caroline Alves de Oliveira
- São Paulo State University, Faculty of Agricultural and Veterinary Sciences, Via de Acesso Prof. Paulo Donato Castellane, 14884-900, Jaboticabal, São Paulo, Brazil
| | - Vinicius Martins Silva
- São Paulo State University, Faculty of Agricultural and Veterinary Sciences, Via de Acesso Prof. Paulo Donato Castellane, 14884-900, Jaboticabal, São Paulo, Brazil
| | - Gabriel Sgarbiero Montanha
- University of São Paulo, Centre for Nuclear Energy in Agriculture, Laboratory of Nuclear Instrumentation, Avenida Centenário, 303, 13400-970, Piracicaba, Brazil
| | - André Rodrigues Dos Reis
- São Paulo State University (UNESP), School of Science and Engineering, Rua Domingos da Costa Lopes 780, 17602-496, Tupã, Brazil.
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Chao W, Rao S, Chen Q, Zhang W, Liao Y, Ye J, Cheng S, Yang X, Xu F. Advances in Research on the Involvement of Selenium in Regulating Plant Ecosystems. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11202712. [PMID: 36297736 PMCID: PMC9607533 DOI: 10.3390/plants11202712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/26/2022] [Accepted: 10/11/2022] [Indexed: 05/15/2023]
Abstract
Selenium is an essential trace element which plays an important role in human immune regulation and disease prevention. Plants absorb inorganic selenium (selenite or selenate) from the soil and convert it into various organic selenides (such as seleno amino acids, selenoproteins, and volatile selenides) via the sulfur metabolic pathway. These organic selenides are important sources of dietary selenium supplementation for humans. Organoselenides can promote plant growth, improve nutritional quality, and play an important regulatory function in plant ecosystems. The release of selenium-containing compounds into the soil by Se hyperaccumulators can promote the growth of Se accumulators but inhibit the growth and distribution of non-Se accumulators. Volatile selenides with specific odors have a deterrent effect on herbivores, reducing their feeding on plants. Soil microorganisms can effectively promote the uptake and transformation of selenium in plants, and organic selenides in plants can improve the tolerance of plants to pathogenic bacteria. Although selenium is not an essential trace element for plants, the right amount of selenium has important physiological and ecological benefits for them. This review summarizes recent research related to the functions of selenium in plant ecosystems to provide a deeper understanding of the significance of this element in plant physiology and ecosystems and to serve as a theoretical basis and technical support for the full exploitation and rational application of the ecological functions of selenium-accumulating plants.
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Affiliation(s)
- Wei Chao
- College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, China
- Engineering Research Center of Ecology and Agricultural Use of Wetland of Ministry of Education, Yangtze University, Jingzhou 434025, China
- Hubei Key Laboratory of Waterlogging Disaster and Agricultural Use of Wetland, Yangtze University, Jingzhou 434025, China
| | - Shen Rao
- National R&D Center for Se-Rich Agricultural Products Processing, School of Modern Industry for Selenium Science and Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Qiangwen Chen
- College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, China
| | - Weiwei Zhang
- College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, China
| | - Yongling Liao
- College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, China
| | - Jiabao Ye
- College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, China
| | - Shuiyuan Cheng
- National R&D Center for Se-Rich Agricultural Products Processing, School of Modern Industry for Selenium Science and Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Xiaoyan Yang
- Henry Fok School of Biology and Agricultural, Shaoguan University, Shaoguan 512005, China
- Correspondence: (X.Y.); or (F.X.)
| | - Feng Xu
- College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, China
- Correspondence: (X.Y.); or (F.X.)
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9
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Kang L, Wu Y, Zhang J, An Q, Zhou C, Li D, Pan C. Nano-selenium enhances the antioxidant capacity, organic acids and cucurbitacin B in melon (Cucumis melo L.) plants. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 241:113777. [PMID: 35738099 DOI: 10.1016/j.ecoenv.2022.113777] [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: 02/02/2022] [Revised: 06/12/2022] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
Pesticides are widely used in melon production causing safety issues around the consumption of melon and increasing pathogen and insect tolerance to pesticides. This study investigated whether a nano-selenium (Nano-Se) spray treatment can improve resistance to biological stress in melon plants, reducing the need for pesticides, and how this mechanism is activated. To achieve this, we examine the ultrastructure and physio-biochemical responses of two melon cultivars after foliar spraying with Nano-Se. Nano-Se treatment reduced plastoglobulins in leaf mesophyll cells, thylakoid films were left intact, and compound starch granules increased. Nano-Se treatment also increased root mitochondria and left nucleoli intact. Nano-Se treatment enhanced ascorbate peroxidase, peroxidase, phenylalanine ammonia lyase, β-1,3-glucanase, chitinase activities and their mRNA levels in treated melon plants compared to control plants (without Nano-Se treatments). Exogenous application of Nano-Se improved fructose, glucose, galactitol, stachyose, lactic acid, tartaric acid, fumaric acid, malic acid and succinic acid in treated plants compared to control plants. In addition, Nano-Se treatment enhanced cucurbitacin B and up-regulated eight cucurbitacin B synthesis-related genes. We conclude that Nano-Se treatment of melon plants triggered antioxidant capacity, photosynthesis, organic acids, and up-regulated cucurbitacin B synthesis-related genes, which plays a comprehensive role in stress resistance in melon plants.
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Affiliation(s)
- Lu Kang
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China; Institute of Agricultural Quality Standards and Testing Technology, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China
| | - Yangliu Wu
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China
| | - Jingbang Zhang
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China
| | - Quanshun An
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China
| | - Chunran Zhou
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China
| | - Dong Li
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China
| | - Canping Pan
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China.
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Zhang P, Li W, Qiu H, Liu M, Li Y, He E. Metal resistant gut microbiota facilitates snails feeding on metal hyperaccumulator plant Sedum alfredii in the phytoremediation field. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 236:113514. [PMID: 35427879 DOI: 10.1016/j.ecoenv.2022.113514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 04/09/2022] [Accepted: 04/09/2022] [Indexed: 06/14/2023]
Abstract
The interactions between hyperaccumulators and their associated herbivores have been mostly investigated in their natural habitats and largely ignored in the phytoremediation practice. Herein, we investigated the herbivory status of Zn/Cd-hyperaccumulating plant Sedum alfredii from both their natural habitats and their applied remediation field, and inspected the adaptive strategies of the herbivores from the perspective of their facilitative gut microbiota. Field investigations showed that snail species Bradybaena ravida was the dominant herbivore feeding on S. alfredii and they can be only found in sites with lower levels of heavy metals compared with the plant natural habitat. Gut microbial community was analyzed using two sequencing methods (16S rRNA and czcA-Zn/Cd resistant gene) to comparatively understand the effect of gut microbes in facilitating snail feeding on the hyperaccumulators. The results revealed significant differences in the diversity and richness between the gut microbiota of the two snail populations, which was more pronounced by the czcA sequencing method. Despite of the compositional differences, their functions seemed to converge into three categories as metal-tolerant and contaminant degraders, gut symbionts, and pathogens. Further function potentials predicted by Tax4Fun based on 16 S sequencing data were in accordance with this categorization as the most abundant metabolic pathways were two-component system and ABC transporter, which was closely related to metal stress adaptation. The prevalence of positive interactions (~80%) indicated by the co-occurrence network analysis based on czcA sequencing data in both groups of gut microbiota further suggested the facilitative effect of these metal-tolerant gut microbes in coping with the high metal diet, which ultimately assist the snails to successfully feed on S. alfredii plants and thrive. This work for the first time provides evidence that the herbivore adaptation to hyperaccumulators were also associated with their gut microbial adaptation to metals.
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Affiliation(s)
- Peihua Zhang
- School of Geographic Sciences, East China Normal University, Shanghai 200241, China; School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Wenxing Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hao Qiu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Min Liu
- School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Ye Li
- School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Erkai He
- School of Geographic Sciences, East China Normal University, Shanghai 200241, China.
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11
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El-Badri AM, Hashem AM, Batool M, Sherif A, Nishawy E, Ayaad M, Hassan HM, Elrewainy IM, Wang J, Kuai J, Wang B, Zheng S, Zhou G. Comparative efficacy of bio-selenium nanoparticles and sodium selenite on morpho-physiochemical attributes under normal and salt stress conditions, besides selenium detoxification pathways in Brassica napus L. J Nanobiotechnology 2022; 20:163. [PMID: 35351148 PMCID: PMC8962572 DOI: 10.1186/s12951-022-01370-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/11/2022] [Indexed: 01/13/2023] Open
Abstract
Selenium nanoparticles (SeNPs) have attracted considerable attention globally due to their significant potential for alleviating abiotic stresses in plants. Accordingly, further research has been conducted to develop nanoparticles using chemical ways. However, our knowledge about the potential benefit or phytotoxicity of bioSeNPs in rapeseed is still unclear. Herein, we investigated the effect of bioSeNPs on growth and physiochemical attributes, and selenium detoxification pathways compared to sodium selenite (Se (IV)) during the early seedling stage under normal and salt stress conditions. Our findings showed that the range between optimal and toxic levels of bioSeNPs was wider than Se (IV), which increased the plant’s ability to reduce salinity-induced oxidative stress. BioSeNPs improved the phenotypic characteristics of rapeseed seedlings without the sign of toxicity, markedly elevated germination, growth, photosynthetic efficiency and osmolyte accumulation versus Se (IV) under normal and salt stress conditions. In addition to modulation of Na+ and K+ uptake, bioSeNPs minimized the ROS level and MDA content by activating the antioxidant enzymes engaged in ROS detoxification by regulating these enzyme-related genes expression patterns. Importantly, the main effect of bioSeNPs and Se (IV) on plant growth appeared to be correlated with the change in the expression levels of Se-related genes. Our qRT-PCR results revealed that the genes involved in Se detoxification in root tissue were upregulated upon Se (IV) treated seedlings compared to NPs, indicating that bioSeNPs have a slightly toxic effect under higher concentrations. Furthermore, bioSeNPs might improve lateral root production by increasing the expression level of LBD16. Taken together, transamination and selenation were more functional methods of Se detoxification and proposed different degradation pathways that synthesized malformed or deformed selenoproteins, which provided essential mechanisms to increase Se tolerance at higher concentrations in rapeseed seedlings. Current findings could add more knowledge regarding the mechanisms underlying bioSeNPs induced plant growth.
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Affiliation(s)
- Ali Mahmoud El-Badri
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.,Field Crops Research Institute, Agricultural Research Center (ARC), Giza, 12619, Egypt
| | - Ahmed M Hashem
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.,Biotechnology Department, Faculty of Agriculture, Al-Azhar University, Cairo, 11651, Egypt
| | - Maria Batool
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Ahmed Sherif
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.,Field Crops Research Institute, Agricultural Research Center (ARC), Giza, 12619, Egypt
| | - Elsayed Nishawy
- Desert Research Center, Genetics Resource Department, Egyptian Deserts Gene Bank, Cairo, 11735, Egypt
| | - Mohammed Ayaad
- Plant Research Department, Nuclear Research Center, Atomic Energy Authority, Abo Zaabal, Cairo, 13795, Egypt
| | - Hamada M Hassan
- Field Crops Research Institute, Agricultural Research Center (ARC), Giza, 12619, Egypt
| | - Ibrahim M Elrewainy
- Field Crops Research Institute, Agricultural Research Center (ARC), Giza, 12619, Egypt
| | - Jing Wang
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Jie Kuai
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Bo Wang
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science & 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
| | - Guangsheng Zhou
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
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12
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Lima LW, Castleberry M, Wangeline AL, Aguirre B, Dall’Acqua S, Pilon-Smits EAH, Schiavon M. Hyperaccumulator Stanleya pinnata: In Situ Fitness in Relation to Tissue Selenium Concentration. PLANTS (BASEL, SWITZERLAND) 2022; 11:690. [PMID: 35270160 PMCID: PMC8912631 DOI: 10.3390/plants11050690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 02/26/2022] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Earlier studies have shown that Stanleya pinnata benefits from selenium hyperaccumulation through ecological benefits and enhanced growth. However, no investigation has assayed the effects of Se hyperaccumulation on plant fitness in the field. This research aimed to analyze how variation in Se accumulation affects S. pinnata fitness, judged from physiological and biochemical performance parameters and herbivory while growing naturally on two seleniferous sites. Natural variation in Se concentration in vegetative and reproductive tissues was determined, and correlations were explored between Se levels with fitness parameters, herbivory damage, and plant defense compounds. Leaf Se concentration varied between 13- and 55-fold in the two populations, averaging 868 and 2482 mg kg−1 dry weight (DW). Furthermore, 83% and 31% of plants from the two populations showed Se hyperaccumulator levels in leaves (>1000 mg kg−1 DW). In seeds, the Se levels varied 3−4-fold and averaged 3372 and 2267 mg kg−1 DW, well above the hyperaccumulator threshold. Plant size and reproductive parameters were not correlated with Se concentration. There was significant herbivory pressure even on the highest-Se plants, likely from Se-resistant herbivores. We conclude that the variation in Se hyperaccumulation did not appear to enhance or compromise S. pinnata fitness in seleniferous habitats within the observed Se range.
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Affiliation(s)
- Leonardo Warzea Lima
- Biology Department, Colorado State University, Fort Collins, CO 80523, USA; (L.W.L.); (M.C.); (E.A.H.P.-S.)
| | - McKenna Castleberry
- Biology Department, Colorado State University, Fort Collins, CO 80523, USA; (L.W.L.); (M.C.); (E.A.H.P.-S.)
| | - Ami L. Wangeline
- Biology Department, Laramie County Community College, Cheyenne, WY 82007, USA; (A.L.W.); (B.A.)
| | - Bernadette Aguirre
- Biology Department, Laramie County Community College, Cheyenne, WY 82007, USA; (A.L.W.); (B.A.)
| | - Stefano Dall’Acqua
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy;
| | | | - Michela Schiavon
- Biology Department, Colorado State University, Fort Collins, CO 80523, USA; (L.W.L.); (M.C.); (E.A.H.P.-S.)
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco, Italy
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13
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Yang H, Yang X, Ning Z, Kwon SY, Li ML, Tack FMG, Kwon EE, Rinklebe J, Yin R. The beneficial and hazardous effects of selenium on the health of the soil-plant-human system: An overview. JOURNAL OF HAZARDOUS MATERIALS 2022; 422:126876. [PMID: 34416699 DOI: 10.1016/j.jhazmat.2021.126876] [Citation(s) in RCA: 69] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/25/2021] [Accepted: 08/07/2021] [Indexed: 06/13/2023]
Abstract
Selenium (Se), which can be both hazardous and beneficial to plants, animals and humans, plays a pivotal role in regulating soil-plant-human ecosystem functions. The biogeochemical behavior of Se and its environmental impact on the soil-plant-human system has received broad attention in the last decades. This review provides a comprehensive understanding of Se biogeochemistry in the soil-plant-human system. The speciation, transformation, bioavailability as well as the beneficial and hazardous effects of Se in the soil-plant-human system are summarized. Several important aspects in Se in the soil-plant-human system are detailed mentioned, including (1) strategies for biofortification in Se-deficient areas and phytoremediation of soil Se in seleniferous areas; (2) factors affecting Se uptake and transport by plants; (3) metabolic pathways of Se in the human body; (4) the interactions between Se and other trace elements in plant and animals, in particular, the detoxification of heavy metals by Se. Important research hotspots of Se biogeochemistry are outlined, including (1) the coupling of soil microbial activity and the Se biogeochemical cycle; (2) the molecular mechanism of Se metabolic in plants and animals; and (3) the application of Se isotopes as a biogeochemical tracer in research. This review provides up-to-date knowledge and guidelines on Se biogeochemistry research.
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Affiliation(s)
- Hui Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Guizhou Academy of Tobacco Science, 550081 Guiyang, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuefeng Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zengping Ning
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Sae Yun Kwon
- Division of Environmental Science & Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam Gu, Pohang 37673, South Korea
| | - Mi-Ling Li
- School of Marine Science and Policy, University of Delaware, Newark, DE 19716 USA
| | - Filip M G Tack
- Ghent University, Department of Green Chemistry and Technology, Ghent, Belgium
| | - Eilhann E Kwon
- Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Guangjin-Gu, Seoul, Republic of Korea
| | - Jörg Rinklebe
- Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Guangjin-Gu, Seoul, Republic of Korea; University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water and Waste Management, Laboratory of Soil and Groundwater Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany
| | - Runsheng Yin
- State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
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14
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Wang D, Rensing C, Zheng S. Microbial reduction and resistance to selenium: Mechanisms, applications and prospects. JOURNAL OF HAZARDOUS MATERIALS 2022; 421:126684. [PMID: 34339989 DOI: 10.1016/j.jhazmat.2021.126684] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/25/2021] [Accepted: 07/16/2021] [Indexed: 06/13/2023]
Abstract
Selenium is an essential trace element for humans, animals and microorganisms. Microbial transformations, in particular, selenium dissimilatory reduction and bioremediation applications have received increasing attention in recent years. This review focuses on multiple Se-reducing pathways under anaerobic and aerobic conditions, and the phylogenetic clustering of selenium reducing enzymes that are involved in these processes. It is emphasized that a selenium reductase may have more than one metabolic function, meanwhile, there are several Se(VI) and/or Se(IV) reduction pathways in a bacterial strain. It is noted that Se(IV)-reducing efficiency is inconsistent with Se(IV) resistance in bacteria. Moreover, we discussed the links of selenium transformations to biogeochemical cycling of other elements, roles of Se-reducing bacteria in soil, plant and digestion system, and the possibility of using functional genes involved in Se transformation as biomarker in different environments. In addition, we point out the gaps and perspectives both on Se transformation mechanisms and applications in terms of bioremediation, Se fortification or dietary supplementation.
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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; College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, 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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15
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Han D, Xiong S, Jia W, Chen S, Wei Y, Shao H, Huang W. Separation of selenium species in plant tissues by high performance liquid chromatography-ultraviolet treatment-hydride generation atomic fluorescence spectrometry using various mobile phases. BIOTECHNOL BIOTEC EQ 2021. [DOI: 10.1080/13102818.2021.1911682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Dan Han
- College of Tobacco Science, Henan Agricultural University, National Tobacco Cultivation and Physiology and Biochemistry Research Center, Key Laboratory for Tobacco Cultivation of Tobacco Industry, Zhengzhou, Henan, PR China
| | - Shuanglian Xiong
- College of Resources and Environment, Huazhong Agricultural University, Microelement Research Center, Wuhan, Hubei, PR China
| | - Wei Jia
- College of Tobacco Science, Henan Agricultural University, National Tobacco Cultivation and Physiology and Biochemistry Research Center, Key Laboratory for Tobacco Cultivation of Tobacco Industry, Zhengzhou, Henan, PR China
| | - Simeng Chen
- College of Tobacco Science, Henan Agricultural University, National Tobacco Cultivation and Physiology and Biochemistry Research Center, Key Laboratory for Tobacco Cultivation of Tobacco Industry, Zhengzhou, Henan, PR China
| | - Yanqiu Wei
- College of Tobacco Science, Henan Agricultural University, National Tobacco Cultivation and Physiology and Biochemistry Research Center, Key Laboratory for Tobacco Cultivation of Tobacco Industry, Zhengzhou, Henan, PR China
| | - Huifang Shao
- College of Tobacco Science, Henan Agricultural University, National Tobacco Cultivation and Physiology and Biochemistry Research Center, Key Laboratory for Tobacco Cultivation of Tobacco Industry, Zhengzhou, Henan, PR China
| | - Wuxing Huang
- College of Tobacco Science, Henan Agricultural University, National Tobacco Cultivation and Physiology and Biochemistry Research Center, Key Laboratory for Tobacco Cultivation of Tobacco Industry, Zhengzhou, Henan, PR China
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16
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Zhang M, Pang Y, Yi Q, Huang J, Huang X, Huang Q, Xu P, Tang S. Comparative effectiveness of Se translocation between low-Se and high-Se rice cultivars under Se fertilization. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 205:111372. [PMID: 32977281 DOI: 10.1016/j.ecoenv.2020.111372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 09/12/2020] [Accepted: 09/14/2020] [Indexed: 05/28/2023]
Abstract
The production of natural selenium (Se)-rich food by using a high-Se crop cultivar is beneficial to human health and environmental safety; however, the underlying mechanism of different Se-accumulation ability between high- and low-Se rice cultivars remains unclear. A low-grain-Se cultivar and high-grain-Se cultivar of rice were used as test materials, and two levels of Se (0 and 0.5 mg kg-1) were arranged in a randomized design containing twelve replicates. The dynamic changes of shoot Se concentration and accumulation, xylem sap Se concentration, shoot and grain Se distribution, Se transporters genes (OsPT2, Sultr1;2, NRT1.1B) expression of the high- and low-Se rice cultivars were determined. The shoot Se concentration and accumulation of the high-Se rice showed a greater degree of reduction than those of the low-Se rice during grain filling stage, indicating that leaves of high-Se rice served as a Se source and supplied more Se for the growth centre grain. The expression levels of OsPT2, NRT1.1B and Sultr1;2 in the high-Se rice cultivar were significantly higher than those in the low-Se rice cultivar, which indicated that the high-Se rice cultivar possessed better transport carriers. The distribution of Se in grain of the high-Se rice cultivar was more uniform, whereas the low-Se cultivar tended to accumulate Se in embryo end. The stronger reutilization of Se from shoots to grains promoted by increased transporters genes expression and optimized grain storage space may explain how the high-Se rice cultivar is able to accumulate more Se in grain.
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Affiliation(s)
- Mu Zhang
- Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Key Laboratory of Plant Nutrition and Fertiliser in South Region, Ministry of Agriculture, Guangzhou, 510640, China; Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation, Guangzhou, 510640, China
| | - Yuwan Pang
- Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Key Laboratory of Plant Nutrition and Fertiliser in South Region, Ministry of Agriculture, Guangzhou, 510640, China; Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation, Guangzhou, 510640, China
| | - Qiong Yi
- Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Key Laboratory of Plant Nutrition and Fertiliser in South Region, Ministry of Agriculture, Guangzhou, 510640, China; Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation, Guangzhou, 510640, China
| | - Jianfeng Huang
- Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Key Laboratory of Plant Nutrition and Fertiliser in South Region, Ministry of Agriculture, Guangzhou, 510640, China; Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation, Guangzhou, 510640, China
| | - Xu Huang
- Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Key Laboratory of Plant Nutrition and Fertiliser in South Region, Ministry of Agriculture, Guangzhou, 510640, China; Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation, Guangzhou, 510640, China
| | - Qiaoyi Huang
- Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Key Laboratory of Plant Nutrition and Fertiliser in South Region, Ministry of Agriculture, Guangzhou, 510640, China; Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation, Guangzhou, 510640, China
| | - Peizhi Xu
- Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Key Laboratory of Plant Nutrition and Fertiliser in South Region, Ministry of Agriculture, Guangzhou, 510640, China; Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation, Guangzhou, 510640, China.
| | - Shuanhu Tang
- Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China; Key Laboratory of Plant Nutrition and Fertiliser in South Region, Ministry of Agriculture, Guangzhou, 510640, China; Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation, Guangzhou, 510640, China.
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17
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Pyrzynska K, Sentkowska A. Selenium in plant foods: speciation analysis, bioavailability, and factors affecting composition. Crit Rev Food Sci Nutr 2020; 61:1340-1352. [PMID: 32363893 DOI: 10.1080/10408398.2020.1758027] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Interest in selenium has been increasing over the past few decades with growing knowledge of its importance to overall health. The ability of several plants to accumulate and transform inorganic selenium forms into its bioactive organic compounds has important implications for human nutrition and health. In this review, we present the studies carried out during the last decade to characterize selenium species produced by different plant foods. Attention is also paid to the effect of selenium treatment on chemical composition and antioxidant properties of plants.
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18
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Wide field imaging energy dispersive X-ray absorption spectroscopy. Sci Rep 2019; 9:17734. [PMID: 31776410 PMCID: PMC6881466 DOI: 10.1038/s41598-019-54287-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 11/01/2019] [Indexed: 11/08/2022] Open
Abstract
A new energy dispersive X-ray absorption spectroscopy (EDXAS) method is presented for simultaneous wide-field imaging and transmission X-ray absorption spectroscopy (XAS) to enable rapid imaging and speciation of elements. Based on spectral K-Edge Subtraction imaging (sKES), a bent Laue imaging system diffracting in the vertical plane was developed on a bend magnet beamline for selenium speciation. The high flux and small vertical focus, forming a wide horizontal line beam for projection imaging and computed tomography applications, is achieved by precise matching of lattice plane orientation and crystal surface (asymmetry angle). The condition generating a small vertical focus for imaging also provides good energy dispersion. Details for achieving sufficient energy and spatial resolution are demonstrated for both full field imaging and computed tomography in quantifying selenium chemical species. While this system has lower sensitivity as it uses transmission and may lack the flux and spatial resolution of a dedicated focused beamline system, it has significant potential in rapid screening of heterogeneous biomedical or environmental systems to correlate metal speciation with function.
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Steven JC, Culver A. The defensive benefit and flower number cost of selenium accumulation in Brassica juncea. AOB PLANTS 2019; 11:plz053. [PMID: 31579109 PMCID: PMC6757350 DOI: 10.1093/aobpla/plz053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 08/12/2019] [Indexed: 06/10/2023]
Abstract
Some plant species accumulate selenium in their tissues in quantities far above soil concentrations, and experiments demonstrate that selenium can serve as a defence against herbivores and pathogens. However, selenium may also cause oxidative stress and reduce growth in plants. We measured growth, selenium accumulation and herbivory in four varieties of the selenium accumulator Brassica juncea to investigate the cost of accumulation as well as its benefit in reducing herbivory. We measured selenium levels, plant size and flower number in four varieties of B. juncea watered with sodium selenate or treated as controls. We also conducted no-choice herbivory trials on leaves from both treatments with the specialist herbivore Pieris rapae. The selenate treatment slightly increased leaf number over the control, but tissue concentrations of selenium and flower number were negatively correlated in some varieties. In herbivory trials, leaves from the plants in the selenate treatment lost less leaf tissue, and the majority of larvae given leaves from selenate-treated plants ate very little leaf tissue at all. In the variety with the highest selenium accumulation, leaves from selenate-treated plants that showed reduced flower production also experienced less herbivory in feeding trials. The protective advantage of greater selenium accumulation may be offset by negative effects on reproduction, and the relatively low level of selenium accumulation in this species as compared to more extreme hyperaccumulators could reflect the minimum level necessary to enhance protection from herbivory.
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Affiliation(s)
- Janet C Steven
- Department of Organismal and Environmental Biology, Christopher Newport University, Newport News, VA, USA
| | - Alexander Culver
- New Horizons Governor’s School for Science and Technology Hampton, VA, USA
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20
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Getting to the Root of Selenium Hyperaccumulation—Localization and Speciation of Root Selenium and Its Effects on Nematodes. SOIL SYSTEMS 2019. [DOI: 10.3390/soilsystems3030047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Elemental hyperaccumulation protects plants from many aboveground herbivores. Little is known about effects of hyperaccumulation on belowground herbivores or their ecological interactions. To examine effects of plant selenium (Se) hyperaccumulation on nematode root herbivory, we investigated spatial distribution and speciation of Se in hyperaccumulator roots using X-ray microprobe analysis, and effects of root Se concentration on root-associated nematode communities. Perennial hyperaccumulators Stanleya pinnata and Astragalus bisulcatus, collected from a natural seleniferous grassland contained 100–1500 mg Se kg−1 root dry weight (DW). Selenium was concentrated in the cortex and epidermis of hyperaccumulator roots, with lower levels in the stele. The accumulated Se consisted of organic (C-Se-C) compounds, indistinguishable from methyl-selenocysteine. The field-collected roots yielded 5–400 nematodes g−1 DW in Baermann funnel extraction, with no correlation between root Se concentration and nematode densities. Even roots containing > 1000 mg Se kg−1 DW yielded herbivorous nematodes. However, greenhouse-grown S. pinnata plants treated with Se had fewer total nematodes than those without Se. Thus, while root Se hyperaccumulation may protect plants from non-specialist herbivorous nematodes, Se-resistant nematode taxa appear to associate with hyperaccumulators in seleniferous habitats, and may utilize high-Se hyperaccumulator roots as food source. These findings give new insight into the ecological implications of plant Se (hyper)accumulation.
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Pilon-Smits EAH. On the Ecology of Selenium Accumulation in Plants. PLANTS (BASEL, SWITZERLAND) 2019; 8:E197. [PMID: 31262007 PMCID: PMC6681216 DOI: 10.3390/plants8070197] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/17/2019] [Accepted: 06/27/2019] [Indexed: 11/17/2022]
Abstract
Plants accumulate and tolerate Se to varying degrees, up to 15,000 mg Se/kg dry weight for Se hyperaccumulators. Plant Se accumulation may exert positive or negative effects on other species in the community. The movement of plant Se into ecological partners may benefit them at low concentrations, but cause toxicity at high concentrations. Thus, Se accumulation can protect plants against Se-sensitive herbivores and pathogens (elemental defense) and reduce surrounding vegetation cover via high-Se litter deposition (elemental allelopathy). While hyperaccumulators negatively impact Se-sensitive ecological partners, they offer a niche for Se-tolerant partners, including beneficial microbial and pollinator symbionts as well as detrimental herbivores, pathogens, and competing plant species. These ecological effects of plant Se accumulation may facilitate the evolution of Se resistance in symbionts. Conversely, Se hyperaccumulation may evolve driven by increasing Se resistance in herbivores, pathogens, or plant neighbors; Se resistance also evolves in mutualist symbionts, minimizing the plant's ecological cost. Interesting topics to address in future research are whether the ecological impacts of plant Se accumulation may affect species composition across trophic levels (favoring Se resistant taxa), and to what extent Se hyperaccumulators form a portal for Se into the local food chain and are important for Se cycling in the local ecosystem.
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22
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Zsiros O, Nagy V, Párducz Á, Nagy G, Ünnep R, El-Ramady H, Prokisch J, Lisztes-Szabó Z, Fári M, Csajbók J, Tóth SZ, Garab G, Domokos-Szabolcsy É. Effects of selenate and red Se-nanoparticles on the photosynthetic apparatus of Nicotiana tabacum. PHOTOSYNTHESIS RESEARCH 2019; 139:449-460. [PMID: 30374728 DOI: 10.1007/s11120-018-0599-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 10/17/2018] [Indexed: 05/24/2023]
Abstract
Selenium (Se) is a natural trace element, which shifts its action in a relatively narrow concentration range from nutritional role to toxicity. Although it has been well established that in plants chloroplasts are among the primary targets, the mechanism of toxicity on photosynthesis is not well understood. Here, we compared selenate and red-allotrope elemental selenium nanoparticles (red nanoSe) in in vitro tobacco cultures to investigate their effects on the structure and functions of the photosynthetic machinery. Selenate at 10 mg/L concentration retarded plant growth; it also led to a decreased chlorophyll content, accompanied with an increase in the carotenoid-to-chlorophyll ratio. Structural examinations of the photosynthetic machinery, using electron microscopy, small-angle neutron scattering and circular dichroism spectroscopy, revealed significant perturbation in the macro-organization of the pigment-protein complexes and sizeable shrinkage in the repeat distance of granum thylakoid membranes. As shown by chlorophyll a fluorescence transient measurements, these changes in the ultrastructure were associated with a significantly diminished photosystem II activity and a reduced performance of the photosynthetic electron transport, and an enhanced capability of non-photochemical quenching. These changes in the structure and function of the photosynthetic apparatus explain, at least in part, the retarded growth of plantlets in the presence of 10 mg/L selenate. In contrast, red nanoSe, even at 100 mg/L and selenate at 1 mg/L, exerted no negative effect on the growth of plantlets and affected only marginally the thylakoid membrane ultrastructure and the photosynthetic functions.
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Affiliation(s)
- Ottó Zsiros
- Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, POB 521, Szeged, 6701, Hungary
| | - Valéria Nagy
- Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, POB 521, Szeged, 6701, Hungary
| | - Árpád Párducz
- Institute of Biophysics, Biological Research Center, Hungarian Academy of Sciences, POB 521, Szeged, 6701, Hungary
| | - Gergely Nagy
- Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, POB 521, Szeged, 6701, Hungary
- Laboratory for Neutron Scattering, Paul Scherrer Institute, 5232, Villigen PSI, Switzerland
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, POB 49, Budapest, 1525, Hungary
| | - Renáta Ünnep
- Laboratory for Neutron Scattering, Paul Scherrer Institute, 5232, Villigen PSI, Switzerland
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, POB 49, Budapest, 1525, Hungary
| | - Hassan El-Ramady
- Department of Soil and Water Sciences, Faculty of Agriculture, Kafrelsheikh Uni, 33516, Kafr El-Sheikh, Egypt
- Department of Agricultural Botany, Plant Physiology and Biotechnology, University of Debrecen, Egyetem ter 1, Debrecen, 4032, Hungary
| | - József Prokisch
- Bio- and Environmental Enegetics Inst., Nano Food Lab, Debrecen University, Boszormenyi 138, Debrecen, 4032, Hungary
| | - Zsuzsa Lisztes-Szabó
- Isotope Climatology and Environmental Research Centre, Institute for Nuclear Research, Hungarian Academy of Sciences, Debrecen, 4026, Hungary
| | - Miklós Fári
- Department of Agricultural Botany, Plant Physiology and Biotechnology, University of Debrecen, Egyetem ter 1, Debrecen, 4032, Hungary
| | - József Csajbók
- Department of Crop Production and Applied Ecology, University of Debrecen, Boszormenyi 138, Debrecen, 4032, Hungary
| | - Szilvia Zita Tóth
- Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, POB 521, Szeged, 6701, Hungary
| | - Győző Garab
- Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, POB 521, Szeged, 6701, Hungary
- Department of Physics, Faculty of Science, Ostrava University, Chittussiho 10, 710 0, Ostrava - Slezská Ostrava, Czech Republic
| | - Éva Domokos-Szabolcsy
- Department of Agricultural Botany, Plant Physiology and Biotechnology, University of Debrecen, Egyetem ter 1, Debrecen, 4032, Hungary.
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Pyrzynska K, Sentkowska A. Liquid chromatographic analysis of selenium species in plant materials. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2018.12.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Li JT, Gurajala HK, Wu LH, van der Ent A, Qiu RL, Baker AJM, Tang YT, Yang XE, Shu WS. Hyperaccumulator Plants from China: A Synthesis of the Current State of Knowledge. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:11980-11994. [PMID: 30272967 DOI: 10.1021/acs.est.8b01060] [Citation(s) in RCA: 130] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Hyperaccumulator plants are the material basis for phytoextraction research and for practical applications in decontaminating polluted soils and industrial wastes. China's high biodiversity and substantial mineral resources make it a global hotspot for hyperaccumulator plant species. Intensive screening efforts over the past 20 years by researchers working in China have led to the discovery of many different hyperaccumulators for a range of elements. In this review, we present the state of knowledge on all currently reported hyperaccumulator species from China, including Cardamine hupingshanensis (selenium, Se), Dicranopteris dichotoma (rare earth elements, REEs), Elsholtzia splendens (copper, Cu), Phytolacca americana (manganese, Mn), Pteris vittata (arsenic, As), Sedum alfredii, and Sedum plumbizincicola (cadmium/zinc, Cd/Zn). This review covers aspects of the ecophysiology and molecular biology of tolerance and hyperaccumulation for each element. The major scientific advances resulting from the study of hyperaccumulator plants in China are summarized and synthesized.
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Affiliation(s)
- Jin-Tian Li
- School of Life Sciences , South China Normal University , Guangzhou 510631 , P.R. China
| | - Hanumanth Kumar Gurajala
- College of Environmental & Resources Science , Zhejiang University , Hangzhou 310058 , P.R. China
| | - Long-Hua Wu
- Institute of Soil Science, Chinese Academy of Sciences , Nanjing 210008 , P.R. China
| | - Antony van der Ent
- Centre for Mined Land Rehabilitation, Sustainable Minerals Institute , The University of Queensland , Brisbane , Australia
- Laboratoire Sols et Environnement, UMR , Université de Lorraine - INRA , Nancy 1120 , France
| | - Rong-Liang Qiu
- School of Environmental Science and Engineering , Sun Yat-sen University , Guangzhou 510275 , P.R. China
| | - Alan J M Baker
- Centre for Mined Land Rehabilitation, Sustainable Minerals Institute , The University of Queensland , Brisbane , Australia
- Laboratoire Sols et Environnement, UMR , Université de Lorraine - INRA , Nancy 1120 , France
- School of BioSciences , The University of Melbourne , Victoria 3010 , Australia
| | - Ye-Tao Tang
- School of Environmental Science and Engineering , Sun Yat-sen University , Guangzhou 510275 , P.R. China
| | - Xiao-E Yang
- College of Environmental & Resources Science , Zhejiang University , Hangzhou 310058 , P.R. China
| | - Wen-Sheng Shu
- School of Life Sciences , South China Normal University , Guangzhou 510631 , P.R. China
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Plant selenium hyperaccumulation- Ecological effects and potential implications for selenium cycling and community structure. Biochim Biophys Acta Gen Subj 2018; 1862:2372-2382. [DOI: 10.1016/j.bbagen.2018.04.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 04/06/2018] [Accepted: 04/23/2018] [Indexed: 11/23/2022]
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Kopittke PM, Punshon T, Paterson DJ, Tappero RV, Wang P, Blamey FPC, van der Ent A, Lombi E. Synchrotron-Based X-Ray Fluorescence Microscopy as a Technique for Imaging of Elements in Plants. PLANT PHYSIOLOGY 2018; 178:507-523. [PMID: 30108140 PMCID: PMC6181034 DOI: 10.1104/pp.18.00759] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 08/07/2018] [Indexed: 05/06/2023]
Abstract
Understanding the distribution of elements within plant tissues is important across a range of fields in plant science. In this review, we examine synchrotron-based x-ray fluorescence microscopy (XFM) as an elemental imaging technique in plant sciences, considering both its historical and current uses as well as discussing emerging approaches. XFM offers several unique capabilities of interest to plant scientists, including in vivo analyses at room temperature and pressure, good detection limits (approximately 1-100 mg kg-1), and excellent resolution (down to 50 nm). This has permitted its use in a range of studies, including for functional characterization in molecular biology, examining the distribution of nutrients in food products, understanding the movement of foliar fertilizers, investigating the behavior of engineered nanoparticles, elucidating the toxic effects of metal(loid)s in agronomic plant species, and studying the unique properties of hyperaccumulating plants. We anticipate that continuing technological advances at XFM beamlines also will provide new opportunities moving into the future, such as for high-throughput screening in molecular biology, the use of exotic metal tags for protein localization, and enabling time-resolved, in vivo analyses of living plants. By examining current and potential future applications, we hope to encourage further XFM studies in plant sciences by highlighting the versatility of this approach.
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Affiliation(s)
- Peter M Kopittke
- University of Queensland, School of Agriculture and Food Sciences, St. Lucia, Queensland 4072, Australia
| | - Tracy Punshon
- Dartmouth College, Department of Biological Sciences, Life Science Center, Hanover, New Hampshire 03755
| | | | - Ryan V Tappero
- Brookhaven National Laboratory, Photon Sciences Division, Upton, New York 11973
| | - Peng Wang
- Nanjing Agricultural University, College of Resources and Environmental Sciences, Nanjing 210095, China
- University of Queensland, Centre for Soil and Environmental Research, School of Agriculture and Food Sciences, St. Lucia, Queensland 4072, Australia
| | - F Pax C Blamey
- University of Queensland, School of Agriculture and Food Sciences, St. Lucia, Queensland 4072, Australia
| | - Antony van der Ent
- University of Queensland, Centre for Mined Land Rehabilitation, Sustainable Minerals Institute, St. Lucia, Queensland 4072, Australia
| | - Enzo Lombi
- University of South Australia, Future Industries Institute, Mawson Lakes, South Australia 5095, Australia
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Lindblom SD, Wangeline AL, Valdez Barillas JR, Devilbiss B, Fakra SC, Pilon-Smits EAH. Fungal Endophyte Alternaria tenuissima Can Affect Growth and Selenium Accumulation in Its Hyperaccumulator Host Astragalus bisulcatus. FRONTIERS IN PLANT SCIENCE 2018; 9:1213. [PMID: 30177943 PMCID: PMC6109757 DOI: 10.3389/fpls.2018.01213] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 07/27/2018] [Indexed: 05/13/2023]
Abstract
Endophytes can enhance plant stress tolerance by promoting growth and affecting elemental accumulation, which may be useful in phytoremediation. In earlier studies, up to 35% elemental selenium (Se0) was found in Se hyperaccumulator Astragalus bisulcatus. Since Se0 can be produced by microbes, the plant Se0 was hypothesized to be microbe-derived. Here we characterize a fungal endophyte of A. bisulcatus named A2. It is common in seeds from natural seleniferous habitat containing 1,000-10,000 mg kg-1 Se. We identified A2 as Alternaria tenuissima via 18S rRNA sequence analysis and morphological characterization. X-ray microprobe analysis of A. bisulcatus seeds that did or did not harbor Alternaria, showed that both contained >90% organic seleno-compounds with C-Se-C configuration, likely methylselenocysteine and glutamyl-methylselenocysteine. The seed Se was concentrated in the embryo, not the seed coat. X-ray microprobe analysis of A2 in pure culture showed the fungus produced Se0 when supplied with selenite, but accumulated mainly organic C-Se-C compounds when supplied with selenate. A2 was completely resistant to selenate up to 300 mg L-1, moderately resistant to selenite (50% inhibition at ∼50 mg Se L-1), but relatively sensitive to methylselenocysteine and to Se extracted from A. bisulcatus (50% inhibition at 25 mg Se L-1). Four-week old A. bisulcatus seedlings derived from surface-sterilized seeds containing endophytic Alternaria were up to threefold larger than seeds obtained from seeds not showing evidence of fungal colonization. When supplied with Se, the Alternaria-colonized seedlings had lower shoot Se and sulfur levels than seedlings from uncolonized seeds. In conclusion, A. tenuissima may contribute to the Se0 observed earlier in A. bisulcatus, and affect host growth and Se accumulation. A2 is sensitive to the Se levels found in its host's tissues, but may avoid Se toxicity by occupying low-Se areas (seed coat, apoplast) and converting plant Se to non-toxic Se0. These findings illustrate the potential for hyperaccumulator endophytes to affect plant properties relevant for phytoremediation. Facultative endophytes may also be applicable in bioremediation and biofortification, owing to their capacity to turn toxic inorganic forms of Se into non-toxic or even beneficial, organic forms with anticarcinogenic properties.
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Affiliation(s)
- Stormy D. Lindblom
- Department of Biology, Colorado State University, Fort Collins, CO, United States
| | - Ami L. Wangeline
- Department of Biology, Laramie County Community College, Cheyenne, WY, United States
| | - Jose R. Valdez Barillas
- Department of Biology, Colorado State University, Fort Collins, CO, United States
- Department of Sciences and Mathematics, Texas A&M University-San Antonio, San Antonio, TX, United States
| | - Berthal Devilbiss
- Department of Biology, Laramie County Community College, Cheyenne, WY, United States
| | - Sirine C. Fakra
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
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28
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Mincey KA, Boyd RS. Elemental defense of nickel hyperaccumulator seeds against a generalist insect granivore. Ecol Res 2018. [DOI: 10.1007/s11284-018-1583-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Katherine Anne Mincey
- Department of Biological SciencesAuburn University101 Rouse Life SciencesAuburnAL36849USA
| | - Robert Stephen Boyd
- Department of Biological SciencesAuburn University101 Rouse Life SciencesAuburnAL36849USA
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Kopittke PM, Wang P, Lombi E, Donner E. Synchrotron-based X-Ray Approaches for Examining Toxic Trace Metal(loid)s in Soil-Plant Systems. JOURNAL OF ENVIRONMENTAL QUALITY 2017; 46:1175-1189. [PMID: 29293828 DOI: 10.2134/jeq2016.09.0361] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Elevated levels of trace metal(loid)s reduce plant growth, both in soils contaminated by industrial activities and in acid agricultural soils. Although the adverse effects of trace metal(loid)s have long been recognized, there remains much unknown both about their behavior in soils, their toxicity to plants, and the mechanisms that plants use to tolerate elevated concentrations. Synchrotron-based approaches are being utilized increasingly in soil-plant systems to examine toxic metal(loid)s. In the present review, brief consideration is given to the theory of synchrotron radiation. Thereafter, we review the use of synchrotron-based approaches for the examination of various trace metal(loid)s in soil-plant systems, including aluminum, chromium, manganese, cobalt, nickel, copper, zinc, arsenic, selenium, and cadmium. Within the context of this review, X-ray absorption spectroscopy (XAS) and X-ray fluorescence microscopy (μ-XRF) are of particular interest. These techniques can provide in situ analyses of the distribution and speciation of metal(loid)s in soil-plant systems. The information presented here serves not only to understand the behavior of trace metals in soil-plant systems, but also to provide examples of the potential applications of synchrotron radiation that can be used to advantage in other studies.
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Schiavon M, Pilon-Smits EAH. The fascinating facets of plant selenium accumulation - biochemistry, physiology, evolution and ecology. THE NEW PHYTOLOGIST 2017; 213:1582-1596. [PMID: 27991670 DOI: 10.1111/nph.14378] [Citation(s) in RCA: 156] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 10/31/2016] [Indexed: 05/20/2023]
Abstract
Contents 1582 I. 1582 II. 1583 III. 1588 IV. 1590 V. 1592 1592 References 1592 SUMMARY: The importance of selenium (Se) for medicine, industry and the environment is increasingly apparent. Se is essential for many species, including humans, but toxic at elevated concentrations. Plant Se accumulation and volatilization may be applied in crop biofortification and phytoremediation. Topics covered here include beneficial and toxic effects of Se on plants, mechanisms of Se accumulation and tolerance in plants and algae, Se hyperaccumulation, and ecological and evolutionary aspects of these processes. Plant species differ in the concentration and forms of Se accumulated, Se partitioning at the whole-plant and tissue levels, and the capacity to distinguish Se from sulfur. Mechanisms of Se hyperaccumulation and its adaptive significance appear to involve constitutive up-regulation of sulfate/selenate uptake and assimilation, associated with elevated concentrations of defense-related hormones. Hyperaccumulation has evolved independently in at least three plant families, probably as an elemental defense mechanism and perhaps mediating elemental allelopathy. Elevated plant Se protects plants from generalist herbivores and pathogens, but also gives rise to the evolution of Se-resistant specialists. Plant Se accumulation affects ecological interactions with herbivores, pollinators, neighboring plants, and microbes. Hyperaccumulation tends to negatively affect Se-sensitive ecological partners while facilitating Se-resistant partners, potentially affecting species composition and Se cycling in seleniferous ecosystems.
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Affiliation(s)
- Michela Schiavon
- Biology Department, Colorado State University, Fort Collins, CO, 80523-1878, USA
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Schiavon M, Pilon-Smits EAH. Selenium Biofortification and Phytoremediation Phytotechnologies: A Review. JOURNAL OF ENVIRONMENTAL QUALITY 2017; 46:10-19. [PMID: 28177413 DOI: 10.2134/jeq2016.09.0342] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The element selenium (Se) is both essential and toxic for most life forms, with a narrow margin between deficiency and toxicity. Phytotechnologies using plants and their associated microbes can address both of these problems. To prevent Se toxicity due to excess environmental Se, plants may be used to phytoremediate Se from soil or water. To alleviate Se deficiency in humans or livestock, crops may be biofortified with Se. These two technologies may also be combined: Se-enriched plant material from phytoremediation could be used as green fertilizer or as fortified food. Plants may also be used to "mine" Se from seleniferous soils. The efficiency of Se phytoremediation and biofortification may be further optimized. Research in the past decades has provided a wealth of knowledge regarding the mechanisms by which plants take up, metabolize, accumulate, and volatilize Se and the role plant-associated microbes play in these processes. Furthermore, ecological studies have revealed important effects of plant Se on interactions with herbivores, detrivores, pollinators, neighboring vegetation, and the plant microbiome. All this knowledge can be exploited in phytotechnology programs to optimize plant Se accumulation, transformation, volatilization, and/or tolerance via plant breeding, genetic engineering, and tailored agronomic practices.
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White PJ. Selenium accumulation by plants. ANNALS OF BOTANY 2016; 117:217-35. [PMID: 26718221 PMCID: PMC4724052 DOI: 10.1093/aob/mcv180] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 09/09/2015] [Accepted: 10/19/2015] [Indexed: 05/19/2023]
Abstract
BACKGROUND Selenium (Se) is an essential mineral element for animals and humans, which they acquire largely from plants. The Se concentration in edible plants is determined by the Se phytoavailability in soils. Selenium is not an essential element for plants, but excessive Se can be toxic. Thus, soil Se phytoavailability determines the ecology of plants. Most plants cannot grow on seleniferous soils. Most plants that grow on seleniferous soils accumulate <100 mg Se kg(-1) dry matter and cannot tolerate greater tissue Se concentrations. However, some plant species have evolved tolerance to Se, and commonly accumulate tissue Se concentrations >100 mg Se kg(-1) dry matter. These plants are considered to be Se accumulators. Some species can even accumulate Se concentrations of 1000-15 000 mg Se kg(-1 )dry matter and are called Se hyperaccumulators. SCOPE This article provides an overview of Se uptake, translocation and metabolism in plants and highlights the possible genetic basis of differences in these between and within plant species. The review focuses initially on adaptations allowing plants to tolerate large Se concentrations in their tissues and the evolutionary origin of species that hyperaccumulate Se. It then describes the variation in tissue Se concentrations between and within angiosperm species and identifies genes encoding enzymes limiting the rates of incorporation of Se into organic compounds and chromosomal loci that might enable the development of crops with greater Se concentrations in their edible portions. Finally, it discusses transgenic approaches enabling plants to tolerate greater Se concentrations in the rhizosphere and in their tissues. CONCLUSIONS The trait of Se hyperaccumulation has evolved several times in separate angiosperm clades. The ability to tolerate large tissue Se concentrations is primarily related to the ability to divert Se away from the accumulation of selenocysteine and selenomethionine, which might be incorporated into non-functional proteins, through the synthesis of less toxic Se metabilites. There is potential to breed or select crops with greater Se concentrations in their edible tissues, which might be used to increase dietary Se intakes of animals and humans.
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Affiliation(s)
- Philip J White
- Ecological Sciences Group, The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK and Distinguished Scientist Fellowship Program, King Saud University, Riyadh 11451, Kingdom of Saudi Arabia
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Sura-de Jong M, Reynolds RJB, Richterova K, Musilova L, Staicu LC, Chocholata I, Cappa JJ, Taghavi S, van der Lelie D, Frantik T, Dolinova I, Strejcek M, Cochran AT, Lovecka P, Pilon-Smits EAH. Selenium hyperaccumulators harbor a diverse endophytic bacterial community characterized by high selenium resistance and plant growth promoting properties. FRONTIERS IN PLANT SCIENCE 2015; 6:113. [PMID: 25784919 PMCID: PMC4345804 DOI: 10.3389/fpls.2015.00113] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/11/2015] [Indexed: 05/07/2023]
Abstract
Selenium (Se)-rich plants may be used to provide dietary Se to humans and livestock, and also to clean up Se-polluted soils or waters. This study focused on endophytic bacteria of plants that hyperaccumulate selenium (Se) to 0.5-1% of dry weight. Terminal restriction fragment length polymorphism (T-RFLP) analysis was used to compare the diversity of endophytic bacteria of hyperaccumulators Stanleya pinnata (Brassicaceae) and Astragalus bisulcatus (Fabaceae) with those from related non-accumulators Physaria bellii (Brassicaceae) and Medicago sativa (Fabaceae) collected on the same, seleniferous site. Hyperaccumulators and non-accumulators showed equal T-RF diversity. Parsimony analysis showed that T-RFs from individuals of the same species were more similar to each other than to those from other species, regardless of plant Se content or spatial proximity. Cultivable endophytes from hyperaccumulators S. pinnata and A. bisulcatus were further identified and characterized. The 66 bacterial morphotypes were shown by MS MALDI-TOF Biotyper analysis and 16S rRNA gene sequencing to include strains of Bacillus, Pseudomonas, Pantoea, Staphylococcus, Paenibacillus, Advenella, Arthrobacter, and Variovorax. Most isolates were highly resistant to selenate and selenite (up to 200 mM) and all could reduce selenite to red elemental Se, reduce nitrite and produce siderophores. Seven isolates were selected for plant inoculation and found to have plant growth promoting properties, both in pure culture and when co-cultivated with crop species Brassica juncea (Brassicaceae) or M. sativa. There were no effects on plant Se accumulation. We conclude that Se hyperaccumulators harbor an endophytic bacterial community in their natural seleniferous habitat that is equally diverse to that of comparable non-accumulators. The hyperaccumulator endophytes are characterized by high Se resistance, capacity to produce elemental Se and plant growth promoting properties.
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Affiliation(s)
- Martina Sura-de Jong
- Department of Biochemistry and Microbiology, University of Chemistry and Technology in PraguePrague, Czech Republic
- Life Sciences and Technology, Van Hall Larenstein University of Applied SciencesLeeuwarden, Netherlands
| | | | - Klara Richterova
- Department of Biochemistry and Microbiology, University of Chemistry and Technology in PraguePrague, Czech Republic
| | - Lucie Musilova
- Department of Biochemistry and Microbiology, University of Chemistry and Technology in PraguePrague, Czech Republic
| | - Lucian C. Staicu
- Biology Department, Colorado State UniversityFort Collins, CO, USA
| | - Iva Chocholata
- Department of Biochemistry and Microbiology, University of Chemistry and Technology in PraguePrague, Czech Republic
| | | | - Safiyh Taghavi
- FMC Corporation, Center of Excellence for Agricultural Biosolutions, Research Triangle ParkNC, USA
| | - Daniel van der Lelie
- FMC Corporation, Center of Excellence for Agricultural Biosolutions, Research Triangle ParkNC, USA
| | - Tomas Frantik
- Institute of Botany, Academy of Sciences of the Czech RepublicPruhonice, Czech Republic
| | - Iva Dolinova
- The Institute for Nanomaterials, Advanced Technology and Innovation, Technical University of LiberecLiberec, Czech Republic
| | - Michal Strejcek
- Department of Biochemistry and Microbiology, University of Chemistry and Technology in PraguePrague, Czech Republic
| | | | - Petra Lovecka
- Department of Biochemistry and Microbiology, University of Chemistry and Technology in PraguePrague, Czech Republic
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El Mehdawi AF, Lindblom SD, Cappa JJ, Fakra SC, Pilon-Smits EAH. Do selenium hyperaccumulators affect selenium speciation in neighboring plants and soil? An X-Ray Microprobe Analysis. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2015; 17:753-65. [PMID: 26030363 DOI: 10.1080/15226514.2014.987374] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Neighbors of Se hyperaccumulators Stanleya pinnata and Astragalus bisulcatus were found earlier to have elevated Se levels. Here we investigate whether Se hyperaccumulators affect Se localization and speciation in surrounding soil and neighboring plants. X-ray fluorescence mapping and X-ray absorption near-edge structure spectroscopy were used to analyze Se localization and speciation in leaves of Artemisia ludoviciana, Symphyotrichum ericoides and Chenopodium album growing next to Se hyperaccumulators or non-accumulators at a seleniferous site. Regardless of neighbors, A. ludoviciana, S. ericoides and C. album accumulated predominantly (73-92%) reduced selenocompounds with XANES spectra similar to the C-Se-C compounds selenomethionine and methyl-selenocysteine. Preliminary data indicate that the largest Se fraction (65-75%), both in soil next to hyperaccumulator S. pinnata and next to nonaccumulator species was reduced Se with spectra similar to C-Se-C standards. These same C-Se-C forms are found in hyperaccumulators. Thus, hyperaccumulator litter may be a source of organic soil Se, but soil microorganisms may also contribute. These findings are relevant for phytoremediation and biofortification since organic Se is more readily accumulated by plants, and more effective for dietary Se supplementation.
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Affiliation(s)
- Ali F El Mehdawi
- a Biology Department , Colorado State University , Fort Collins , CO
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Characterization of a selenium-tolerant rhizosphere strain from a novel Se-hyperaccumulating plant Cardamine hupingshanesis. ScientificWorldJournal 2014; 2014:108562. [PMID: 25478582 PMCID: PMC4247970 DOI: 10.1155/2014/108562] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 10/04/2014] [Accepted: 10/05/2014] [Indexed: 11/17/2022] Open
Abstract
A novel selenium- (Se-) hyperaccumulating plant, Cardamine hupingshanesis, accumulating Se as a form of SeCys2, was discovered in Enshi, Hubei, China, which could not be explained by present selenocysteine methyltransferase (SMT) theory. However, it is interesting to investigate if rhizosphere bacteria play some roles during SeCys2 accumulation. Here, one Se-tolerant rhizosphere strain, Microbacterium oxydans, was isolated from C. hupingshanesis. Phylogenetic analysis and 16S rRNA gene sequences determined the strain as a kind of Gram positive bacillus and belonged to the family Brevibacterium frigoritolerans. Furthermore, Se tolerance test indicated the strain could grow in extreme high Se level of 15.0 mg Se L(-1). When exposed to 1.5 mg Se L(-1), SeCys2 was the predominant Se species in the bacteria, consistent with the Se species in C. hupingshanesis. This coincidence might reveal that this strain played some positive effect in SeCys2 accumulation of C. hupingshanesis. Moreover, when exposed to 1.5 mg Se L(-1) or 15.0 mg Se L(-1), As absorption diminished in the logarithmic phase. In contrast, As absorption increased when exposed to 7.5 mg Se L(-1), indicating As metabolism processes could be affected by Se on this strain. The present study provided a sight on the role of rhizosphere bacteria during Se accumulation for Se-hyperaccumulating plant.
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Pushie MJ, Pickering I, Korbas M, Hackett MJ, George GN. Elemental and chemically specific X-ray fluorescence imaging of biological systems. Chem Rev 2014; 114:8499-541. [PMID: 25102317 PMCID: PMC4160287 DOI: 10.1021/cr4007297] [Citation(s) in RCA: 174] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Indexed: 12/13/2022]
Affiliation(s)
- M. Jake Pushie
- Molecular
and Environmental Sciences Research Group, Department of Geological
Sciences, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada
| | - Ingrid
J. Pickering
- Molecular
and Environmental Sciences Research Group, Department of Geological
Sciences, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada
- Toxicology
Centre, University of Saskatchewan, Saskatoon, SK S7N 5B3, Canada
- Department
of Chemistry, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada
| | - Malgorzata Korbas
- Canadian
Light Source Inc., 44
Innovation Boulevard, Saskatoon, SK S7N 2V3, Canada
- Department
of Anatomy and Cell Biology, University
of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Mark J. Hackett
- Molecular
and Environmental Sciences Research Group, Department of Geological
Sciences, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada
| | - Graham N. George
- Molecular
and Environmental Sciences Research Group, Department of Geological
Sciences, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada
- Toxicology
Centre, University of Saskatchewan, Saskatoon, SK S7N 5B3, Canada
- Department
of Chemistry, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada
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Cappa JJ, Pilon-Smits EAH. Evolutionary aspects of elemental hyperaccumulation. PLANTA 2014; 239:267-75. [PMID: 24463931 DOI: 10.1007/s00425-013-1983-0] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 10/14/2013] [Indexed: 05/08/2023]
Abstract
Hyperaccumulation is the uptake of one or more metal/metalloids to concentrations greater than 50-100× those of the surrounding vegetation or 100-10,000 mg/kg dry weight depending on the element. Hyperaccumulation has been documented in at least 515 taxa of angiosperms. By mapping the occurrence of hyperaccumulators onto the angiosperm phylogeny, we show hyperaccumulation has had multiple origins across the angiosperms. Even within a given order, family or genus, there are typically multiple origins of hyperaccumulation, either for the same or different elements. We address which selective pressures may have led to the evolution of hyperaccumulation and whether there is evidence for co-evolution with ecological partners. Considerable evidence supports the elemental-defense hypothesis, which states that hyperaccumulated elements protect the plants from herbivores and pathogens. There is also evidence that hyperaccumulation can result in drought stress protection, allelopathic effects or physiological benefits. In many instances, ecological partners of hyperaccumulators have evolved resistance to the hyperaccumulated element, indicating co-evolution. Studies on the molecular evolution of hyperaccumulation have pinpointed gene duplication as a common cause of increased metal transporter abundance. Hypertolerance to the hyperaccumulated element often relies upon chelating agents, such as organic acids (e.g., malate, citrate) or peptide/protein chelators that can facilitate transport and sequestration. We conclude the review with a summary and suggested future directions for hyperaccumulator research.
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Affiliation(s)
- Jennifer J Cappa
- Department of Biology, Colorado State University, Fort Collins, CO, 80523-1878, USA
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