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Spiridon A, Oburger E, Valadbeigi Y, Kloimböck T, Stanetty C, Kratena N, Draskovits M, Causon T, Hann S. Surveying the mugineic acid family: Ion mobility - quadrupole time-of-flight mass spectrometry (IM-QTOFMS) characterization and tandem mass spectrometry (LC-ESI-MS/MS) quantification of all eight naturally occurring phytosiderophores. Anal Chim Acta 2023; 1278:341718. [PMID: 37709429 DOI: 10.1016/j.aca.2023.341718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/21/2023] [Accepted: 08/13/2023] [Indexed: 09/16/2023]
Abstract
Phytosiderophores (PS) are root exudates released by grass species (Poaceae) that play a pivotal role in iron (Fe) plant nutrition. A direct determination of PS in biological samples is of paramount importance in understanding micronutrient acquisition mediated by PS. To date, eight plant-born PS have been identified; however, no analytical procedure is currently available to quantify all eight PS simultaneously with high analytical confidence. With access to the full set of PS standards for the first time, we report comprehensive methods to both fully characterize (IM-QTOFMS) and quantify (LC-ESI-MS/MS) all eight naturally occurring PS belonging to the mugineic acid family. The quantitative method was fully validated, yielding linear results for all eight analytes, and no unwanted interferences with soil and plant matrices were observed. LOD and LOQ values determined for each PS were below 11 and 35 nmol L-1, respectively. The method's precision under reproducibility conditions (intra- and inter-day) of measurement was less than 2.5% RSD for all analytes. Additionally, all PS were annotated with high-resolution mass spectrometric fragment spectra and further characterized via drift tube ion mobility-mass spectrometry. The collision cross-sections obtained for primary ion species yielded a valuable database for future research focused on in-depth PS studies. The new quantitative method was applied to analyse root exudates from Fe-controlled and deficient barley, oat, rye, and sorghum plants. All eight PS, including mugineic acid (MA), 3"-hydroxymugineic acid (HMA), 3"-epi-hydroxymugineic acid (epi-HMA), hydroxyavenic acid (HAVA), deoxymugineic acid (DMA), 3"-hydroxydeoxymugineic acid (HDMA), 3"-epi-hydroxydeoxymugineic acid (epi-HDMA) and avenic acid (AVA) were for the first time successfully identified and quantified in root exudates of various graminaceous plants using a single analytical procedure. These newly developed methods can be applied to studies aimed at improving crop yield and micronutrient grain content for food consumption via plant-based biofortification.
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Affiliation(s)
- Andreea Spiridon
- University of Natural Resources and Life Sciences, Department of Forest and Soil Science, Institute of Soil Research, Konrad Lorenz-Strasse 24/I, 3430, Tulln an der Donau, Austria
| | - Eva Oburger
- University of Natural Resources and Life Sciences, Department of Forest and Soil Science, Institute of Soil Research, Konrad Lorenz-Strasse 24/I, 3430, Tulln an der Donau, Austria
| | - Younes Valadbeigi
- University of Natural Resources and Life Sciences, Department of Chemistry, Institute of Analytical Chemistry, Muthgasse 18, 1190, Vienna, Austria
| | - Tobias Kloimböck
- University of Natural Resources and Life Sciences, Department of Forest and Soil Science, Institute of Soil Research, Konrad Lorenz-Strasse 24/I, 3430, Tulln an der Donau, Austria
| | - Christian Stanetty
- Vienna University of Technology (TU Wien), Institute of Applied Synthetic Chemistry, Getreidemarkt 9, 1060, Vienna, Austria
| | - Nicolas Kratena
- Vienna University of Technology (TU Wien), Institute of Applied Synthetic Chemistry, Getreidemarkt 9, 1060, Vienna, Austria
| | - Markus Draskovits
- Vienna University of Technology (TU Wien), Institute of Applied Synthetic Chemistry, Getreidemarkt 9, 1060, Vienna, Austria
| | - Tim Causon
- University of Natural Resources and Life Sciences, Department of Chemistry, Institute of Analytical Chemistry, Muthgasse 18, 1190, Vienna, Austria
| | - Stephan Hann
- University of Natural Resources and Life Sciences, Department of Chemistry, Institute of Analytical Chemistry, Muthgasse 18, 1190, Vienna, Austria.
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(±)-Catechin—A Mass-Spectrometry-Based Exploration Coordination Complex Formation with FeII and FeIII. Cells 2022; 11:cells11060958. [PMID: 35326409 PMCID: PMC8946835 DOI: 10.3390/cells11060958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 03/03/2022] [Accepted: 03/07/2022] [Indexed: 02/06/2023] Open
Abstract
Catechin is an extensively investigated plant flavan-3-ol with a beneficial impact on human health that is often associated with antioxidant activities and iron coordination complex formation. The aim of this study was to explore these properties with FeII and FeIII using a combination of nanoelectrospray-mass spectrometry, differential pulse voltammetry, site-specific deoxyribose degradation assay, FeII autoxidation assay, and brine shrimp mortality assay. Catechin primarily favored coordination complex formation with Fe ions of the stoichiometry catechin:Fe in the ratio of 1:1 or 2:1. In the detected Fe–catechin coordination complexes, FeII prevailed. Differential pulse voltammetry, the site-specific deoxyribose degradation, and FeII autoxidation assays proved that coordination complex formation affected catechin’s antioxidant effects. In situ formed Fe–catechin coordination complexes showed no toxic activities in the brine shrimp mortality assay. In summary, catechin has properties for the possible treatment of pathological processes associated with ageing and degeneration, such as Alzheimer’s and Parkinson’s diseases.
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Dey S, Regon P, Kar S, Panda SK. Chelators of iron and their role in plant's iron management. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2020; 26:1541-1549. [PMID: 32801485 PMCID: PMC7415063 DOI: 10.1007/s12298-020-00841-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 05/27/2020] [Accepted: 06/20/2020] [Indexed: 06/11/2023]
Abstract
Proper transport of metal and their homeostasis is very crucial for the growth and development of plants. Plants root are the primary organs which comes in contact with the stress and thus few modifications occurs, often determining the nutrient efficiency or sometimes as a stress tolerance mechanism. Plant utilizes two strategies for the uptake of iron viz, strategy I-reduction based and strategy II-chelation based. In this review we attempted for a better understanding of how the chelators acts in the mechanism of iron uptake from soils to plants and how iron is distributed in the plants.
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Affiliation(s)
- Sangita Dey
- Department of Life Science and Bioinformatics, Assam University, Silchar, 788011 India
| | - Preetom Regon
- Department of Life Science and Bioinformatics, Assam University, Silchar, 788011 India
| | - Saradia Kar
- Department of Life Science and Bioinformatics, Assam University, Silchar, 788011 India
| | - Sanjib Kumar Panda
- Department of Life Science and Bioinformatics, Assam University, Silchar, 788011 India
- Department of Biochemistry, Central University of Rajasthan, Ajmer, Rajasthan 305817 India
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4
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Flis P, Ouerdane L, Grillet L, Curie C, Mari S, Lobinski R. Inventory of metal complexes circulating in plant fluids: a reliable method based on HPLC coupled with dual elemental and high-resolution molecular mass spectrometric detection. THE NEW PHYTOLOGIST 2016; 211:1129-41. [PMID: 27111838 DOI: 10.1111/nph.13964] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 03/10/2016] [Indexed: 05/16/2023]
Abstract
Description of metal species in plant fluids such as xylem, phloem or related saps remains a complex challenge usually addressed either by liquid chromatography-mass spectrometry, X-ray analysis or computational prediction. To date, none of these techniques has achieved a complete and true picture of metal-containing species in plant fluids, especially for the least concentrated complexes. Here, we present a generic analytical methodology for a large-scale (> 10 metals, > 50 metal complexes) detection, identification and semiquantitative determination of metal complexes in the xylem and embryo sac liquid of the green pea, Pisum sativum. The procedure is based on direct injection using hydrophilic interaction chromatography with dual detection by elemental (inductively coupled plasma mass spectrometry) and molecular (high-resolution electrospray mass spectrometry) mass spectrometric detection. Numerous and novel complexes of iron(II), iron(III), copper(II), zinc, manganese, cobalt(II), cobalt(III), magnesium, calcium, nickel and molybdenum(IV) with several ligands including nicotianamine, citrate, malate, histidine, glutamine, aspartic acid, asparagine, phenylalanine and others are observed in pea fluids and discussed. This methodology provides a large inventory of various types of metal complexes, which is a significant asset for future biochemical and genetic studies into metal transport/homeostasis.
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Affiliation(s)
- Paulina Flis
- Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les Matériaux (UMR5254), Centre National de la Recherche Scientifique, Université de Pau et des Pays de l'Adour, Pau Cedex 9, F-64063, France
| | - Laurent Ouerdane
- Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les Matériaux (UMR5254), Centre National de la Recherche Scientifique, Université de Pau et des Pays de l'Adour, Pau Cedex 9, F-64063, France
| | - Louis Grillet
- Laboratoire de Biochimie et Physiologie Moléculaire des Plantes (BPMP), Institut de Biologie Intégrative des Plantes, Centre National de la Recherche Scientifique (UMR5004), Institut National de la Recherche Agronomique, Université Montpellier II, Ecole Nationale Supérieure d'Agronomie, Montpellier Cedex 2, F-34060, France
| | - Catherine Curie
- Laboratoire de Biochimie et Physiologie Moléculaire des Plantes (BPMP), Institut de Biologie Intégrative des Plantes, Centre National de la Recherche Scientifique (UMR5004), Institut National de la Recherche Agronomique, Université Montpellier II, Ecole Nationale Supérieure d'Agronomie, Montpellier Cedex 2, F-34060, France
| | - Stéphane Mari
- Laboratoire de Biochimie et Physiologie Moléculaire des Plantes (BPMP), Institut de Biologie Intégrative des Plantes, Centre National de la Recherche Scientifique (UMR5004), Institut National de la Recherche Agronomique, Université Montpellier II, Ecole Nationale Supérieure d'Agronomie, Montpellier Cedex 2, F-34060, France
| | - Ryszard Lobinski
- Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les Matériaux (UMR5254), Centre National de la Recherche Scientifique, Université de Pau et des Pays de l'Adour, Pau Cedex 9, F-64063, France
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5
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Pluháček T, Lemr K, Ghosh D, Milde D, Novák J, Havlíček V. Characterization of microbial siderophores by mass spectrometry. MASS SPECTROMETRY REVIEWS 2016; 35:35-47. [PMID: 25980644 DOI: 10.1002/mas.21461] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 12/19/2014] [Indexed: 05/28/2023]
Abstract
Siderophores play important roles in microbial iron piracy, and are applied as infectious disease biomarkers and novel pharmaceutical drugs. Inductively coupled plasma and molecular mass spectrometry (ICP-MS) combined with high resolution separations allow characterization of siderophores in complex samples taking advantages of mass defect data filtering, tandem mass spectrometry, and iron-containing compound quantitation. The enrichment approaches used in siderophore analysis and current ICP-MS technologies are reviewed. The recent tools for fast dereplication of secondary metabolites and their databases are reported. This review on siderophores is concluded with their recent medical, biochemical, geochemical, and agricultural applications in mass spectrometry context.
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Affiliation(s)
- Tomáš Pluháček
- Department of Analytical Chemistry, Faculty of Science, Regional Centre of Advanced Technologies and Materials, Palacky University, 17. listopadu 12, 771 46, Olomouc, Czech Republic
- Institute of Microbiology, AS CR v.v.i., Videnska 1083, CZ 142 20, Prague 4, Czech Republic
| | - Karel Lemr
- Department of Analytical Chemistry, Faculty of Science, Regional Centre of Advanced Technologies and Materials, Palacky University, 17. listopadu 12, 771 46, Olomouc, Czech Republic
- Institute of Microbiology, AS CR v.v.i., Videnska 1083, CZ 142 20, Prague 4, Czech Republic
| | - Dipankar Ghosh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, 110067, India
| | - David Milde
- Department of Analytical Chemistry, Faculty of Science, Regional Centre of Advanced Technologies and Materials, Palacky University, 17. listopadu 12, 771 46, Olomouc, Czech Republic
| | - Jiří Novák
- Institute of Microbiology, AS CR v.v.i., Videnska 1083, CZ 142 20, Prague 4, Czech Republic
| | - Vladimír Havlíček
- Department of Analytical Chemistry, Faculty of Science, Regional Centre of Advanced Technologies and Materials, Palacky University, 17. listopadu 12, 771 46, Olomouc, Czech Republic
- Institute of Microbiology, AS CR v.v.i., Videnska 1083, CZ 142 20, Prague 4, Czech Republic
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Chobot V, Hadacek F, Weckwerth W, Kubicova L. Iron chelation and redox chemistry of anthranilic acid and 3-hydroxyanthranilic acid: A comparison of two structurally related kynurenine pathway metabolites to obtain improved insights into their potential role in neurological disease development. J Organomet Chem 2015; 782:103-110. [PMID: 25892823 PMCID: PMC4396858 DOI: 10.1016/j.jorganchem.2015.01.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 01/07/2015] [Accepted: 01/08/2015] [Indexed: 01/04/2023]
Abstract
Anthranilic acid (ANA) and 3-hydroxyanthranilic acid (3-HANA) are kynurenine pathway intermediates of the tryptophan metabolism. A hitherto unemployed method combination, differential pulse voltammetry, mass spectrometry (nano-ESI-MS), deoxyribose degradation and iron(II) autoxidation assays has been employed for studying of their redox chemistry and their interactions with iron(II) and iron(III) ions. Both acids inhibited the Fenton reaction by iron chelation and ROS scavenging in the deoxyribose degradation assay. In the iron(II) autoxidation assay, anthranilic acid showed antioxidant effects, whereas 3-hydroxyanthranilic acid exhibited apparent pro-oxidant activity. The differential pulse voltammograms of free metabolites and their iron(II) coordination complexes reflected these properties. Nano-ESI-MS confirmed ANA and 3-HANA as efficient iron(II) chelators, both of which form coordination complexes of ligand:iron(II) ratio 1:1, 2:1, and 3:1. In addition, nano-ESI-MS analyses of the oxidation effects by hydroxyl radical attack identified 3-HANA as strikingly more susceptible than ANA. 3-HANA susceptibility to oxidation may explain its decreased concentrations in the reaction mixture. The presented observations can add to explaining why 3-HANA levels decrease in patients with some neurological and other diseases which can often associated with elevated concentrations of ROS.
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Affiliation(s)
- Vladimir Chobot
- Division of Molecular Systems Biology, Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna A-1090, Austria
| | - Franz Hadacek
- Plant Biochemistry, Albrecht-von-Haller Institut, Georg-August-Universität Göttingen, Justus-von-Liebig-Weg 11, Göttingen D-37077, Germany
| | - Wolfram Weckwerth
- Division of Molecular Systems Biology, Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna A-1090, Austria
| | - Lenka Kubicova
- Division of Molecular Systems Biology, Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna A-1090, Austria
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7
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Kubicova L, Hadacek F, Weckwerth W, Chobot V. Effects of endogenous neurotoxin quinolinic acid on reactive oxygen species production by Fenton reaction catalyzed by iron or copper. J Organomet Chem 2015; 782:111-115. [PMID: 25892824 PMCID: PMC4396856 DOI: 10.1016/j.jorganchem.2015.01.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/04/2015] [Accepted: 01/14/2015] [Indexed: 11/06/2022]
Abstract
The tryptophan metabolite, quinolinic (2,3-pyridinedicarboxylic) acid, is known as an endogenous neurotoxin. Quinolinic acid can form coordination complexes with iron or copper. The effects of quinolinic acid on reactive oxygen species production in the presence of iron or copper were explored by a combination of chemical assays, classical site-specific and ascorbic acid-free variants of the deoxyribose degradation assay, and mass spectrometry (ESI–MS). Quinolinic acid showed evident antioxidant activity in chemical assays, but the effect was more pronounced in the presence of copper as transition metal catalyst than in presence of iron. Nano-ESI–MS confirmed the ability of quinolinic acid to form coordination complexes with iron(II) or copper(II) and quinolinic acid stability against oxidative attack by hydroxyl radicals. The results illustrate a highly milieu-dependent quinolinic acid chemistry when it enters reactions as competitive ligand. Quinolinic acid is considered as a neurotoxin but it can also act as an antioxidant. MS proves quinolinic acid's ability to form coordination complexes with Fe or Cu. Quinolinic acid showed a relative robustness when under oxidative attack. Quinolinic acid can protect cells suffering from the elevated oxidative stress.
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Affiliation(s)
- Lenka Kubicova
- Division of Molecular Systems Biology, Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna A-1090, Austria
| | - Franz Hadacek
- Plant Biochemistry, Albrecht-von-Haller Institut, Georg-August-Universität Göttingen, Justus-von-Liebig-Weg 11, Göttingen D-37077, Germany
| | - Wolfram Weckwerth
- Division of Molecular Systems Biology, Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna A-1090, Austria
| | - Vladimir Chobot
- Division of Molecular Systems Biology, Department of Ecogenomics and Systems Biology, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna A-1090, Austria
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Murata Y, Itoh Y, Iwashita T, Namba K. Transgenic petunia with the iron(III)-phytosiderophore transporter gene acquires tolerance to iron deficiency in alkaline environments. PLoS One 2015; 10:e0120227. [PMID: 25781941 PMCID: PMC4363515 DOI: 10.1371/journal.pone.0120227] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 01/20/2015] [Indexed: 11/24/2022] Open
Abstract
Iron is an essential nutrient for all plants. However, terrestrial plants often suffer from iron deficiency in alkaline soil due to its extremely low solubility. Alkaline soil accounts for about 30% of all cultivated ground in the world. Plants have evolved two distinct strategies, I and II, for iron uptake from the soil. Dicots and non-graminaceous monocots use Strategy I, which is primarily based on the reduction of iron(III) to iron(II) and the uptake of iron(II) by the iron-regulated transporter, IRT1. In contrast, graminaceous plants use Strategy II to efficiently acquire insoluble iron(III). Strategy II comprises the synthesis and secretion of iron-chelating phytosiderophores, such as mugineic acids and the Yellow Stripe 1 transporter proteins of the iron(III)-phytosiderophore complex. Barley, which exhibits the highest tolerance to iron deficiency in alkaline soil among graminaceous plants, utilizes mugineic acids and the specific iron(III)-mugineic acids transporter, HvYS1. In this study, we established the transgenic plant Petunia hybrida, which originally had only Strategy I, by introducing the HvYS1 transporter gene derived from barley. When the transgenic plants were grown hydroponically in media containing the iron(III)-2′-deoxymugineic acid complex, free 2′-deoxymugineic acid and its iron(III) complex were detected in the root extract of the transgenic plant by electrospray ionization-Fourier transform-ion cyclotron resonance mass spectrometry. The growth of the transgenic petunia was significantly better than that of the control host in alkaline conditions. Consequently, the transgenic plant acquired a significantly enhanced tolerance to alkaline hydroponic media in the presence of the iron(III)-2′-deoxymugineic acid complex. Furthermore, the flower color of the transgenic plant deepened. The results showed that iron-phytosiderophore complexes and their transporters can potentially be utilized to overcome the worldwide iron uptake problems to diverse plant species that are found in areas with alkaline conditions.
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Affiliation(s)
- Yoshiko Murata
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
- * E-mail:
| | - Yoshiyuki Itoh
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| | - Takashi Iwashita
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| | - Kosuke Namba
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
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9
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Oberacher H, Pitterl F, Erb R, Plattner S. Mass spectrometric methods for monitoring redox processes in electrochemical cells. MASS SPECTROMETRY REVIEWS 2015; 34:64-92. [PMID: 24338642 PMCID: PMC4286209 DOI: 10.1002/mas.21409] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 07/24/2013] [Accepted: 08/12/2013] [Indexed: 06/03/2023]
Abstract
Electrochemistry (EC) is a mature scientific discipline aimed to study the movement of electrons in an oxidation-reduction reaction. EC covers techniques that use a measurement of potential, charge, or current to determine the concentration or the chemical reactivity of analytes. The electrical signal is directly converted into chemical information. For in-depth characterization of complex electrochemical reactions involving the formation of diverse intermediates, products and byproducts, EC is usually combined with other analytical techniques, and particularly the hyphenation of EC with mass spectrometry (MS) has found broad applicability. The analysis of gases and volatile intermediates and products formed at electrode surfaces is enabled by differential electrochemical mass spectrometry (DEMS). In DEMS an electrochemical cell is sampled with a membrane interface for electron ionization (EI)-MS. The chemical space amenable to EC/MS (i.e., bioorganic molecules including proteins, peptides, nucleic acids, and drugs) was significantly increased by employing electrospray ionization (ESI)-MS. In the simplest setup, the EC of the ESI process is used to analytical advantage. A limitation of this approach is, however, its inability to precisely control the electrochemical potential at the emitter electrode. Thus, particularly for studying mechanistic aspects of electrochemical processes, the hyphenation of discrete electrochemical cells with ESI-MS was found to be more appropriate. The analytical power of EC/ESI-MS can further be increased by integrating liquid chromatography (LC) as an additional dimension of separation. Chromatographic separation was found to be particularly useful to reduce the complexity of the sample submitted either to the EC cell or to ESI-MS. Thus, both EC/LC/ESI-MS and LC/EC/ESI-MS are common.
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Affiliation(s)
- Herbert Oberacher
- Institute of Legal Medicine and Core Facility Metabolomics, Innsbruck Medical UniversityInnsbruck, Austria
| | - Florian Pitterl
- Institute of Legal Medicine and Core Facility Metabolomics, Innsbruck Medical UniversityInnsbruck, Austria
| | - Robert Erb
- Institute of Legal Medicine and Core Facility Metabolomics, Innsbruck Medical UniversityInnsbruck, Austria
| | - Sabine Plattner
- Institute of Legal Medicine and Core Facility Metabolomics, Innsbruck Medical UniversityInnsbruck, Austria
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Ostrowski W. Curcuminoids and acetylacetone: iron complexes as studied by electrospray ionization mass spectrometry. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2015; 21:45-50. [PMID: 25906034 DOI: 10.1255/ejms.1331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Curcumin complexes with iron ions were investigated by electrospray ionization mass spectrometry. It was shown that in methanol solutions of curcumin and iron(III) ions, complexes are formed with a stoichiometry of 1 : 1, 2 : or 3 : 1. Curcumi-iron(II) complexes were created only with the 1 : 1 stoichiometry. Abundances of the 1 : 1 ions depend on the source of iron [(II) or (III)] and the reduction process of iron(III) by higher cone- voltage values. A counter-ion for the iron cation does not affect the types of formed complexes. For comparison, methanol solutions of acetylacetone (acac) and mixtures of acac and curcumin with iron salts were also investigated.
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Affiliation(s)
- Wojciech Ostrowski
- Adam Mickiewicz University in Poznań, Faculty of Chemistry, Umultowska 89B, 61-614 Poznań, Poland.
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11
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Álvarez-Fernández A, Díaz-Benito P, Abadía A, López-Millán AF, Abadía J. Metal species involved in long distance metal transport in plants. FRONTIERS IN PLANT SCIENCE 2014; 5:105. [PMID: 24723928 PMCID: PMC3971170 DOI: 10.3389/fpls.2014.00105] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 03/04/2014] [Indexed: 05/19/2023]
Abstract
The mechanisms plants use to transport metals from roots to shoots are not completely understood. It has long been proposed that organic molecules participate in metal translocation within the plant. However, until recently the identity of the complexes involved in the long-distance transport of metals could only be inferred by using indirect methods, such as analyzing separately the concentrations of metals and putative ligands and then using in silico chemical speciation software to predict metal species. Molecular biology approaches also have provided a breadth of information about putative metal ligands and metal complexes occurring in plant fluids. The new advances in analytical techniques based on mass spectrometry and the increased use of synchrotron X-ray spectroscopy have allowed for the identification of some metal-ligand species in plant fluids such as the xylem and phloem saps. Also, some proteins present in plant fluids can bind metals and a few studies have explored this possibility. This study reviews the analytical challenges researchers have to face to understand long-distance metal transport in plants as well as the recent advances in the identification of the ligand and metal-ligand complexes in plant fluids.
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Affiliation(s)
| | | | | | | | - Javier Abadía
- Plant Nutrition Department, Aula Dei Experimental Station (CSIC)Zaragoza, Spain
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12
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Tsednee M, Mak YW, Chen YR, Yeh KC. A sensitive LC-ESI-Q-TOF-MS method reveals novel phytosiderophores and phytosiderophore-iron complexes in barley. THE NEW PHYTOLOGIST 2012; 195:951-961. [PMID: 22709335 DOI: 10.1111/j.1469-8137.2012.04206.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The direct analysis of phytosiderophores (PSs) and their metal complexes in plants is critical to understanding the biological functions of different PSs. Here we report on a rapid and highly sensitive liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-Q-TOF-MS) method for the direct and simultaneous determination of free PSs and their ferric complexes in plants. In addition to previously reported PSs--deoxymugineic acid (DMA), mugineic acid (MA) and epihydroxymugineic acid (epi-HMA)--two more PSs, avenic acid (AVA) and hydroxyavenic acid (HAVA), were identified by this method in roots of Hordeum vulgare cv Himalaya and in root exudates under iron (Fe) deficiency. The two identified PSs could be responsible for Fe acquisition under Fe deficiency because of their relative abundance and ability to form ferric complexes in secreted root exudates. This LC-ESI-Q-TOF-MS method greatly facilitates the identification of free PSs and PS-Fe complexes in one plant sample.
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Affiliation(s)
- Munkhtsetseg Tsednee
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
- Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, National Chung-Hsing University and Academia Sinica, Taipei, Taiwan
- Graduate Institute of Biotechnology and Department of Life Sciences, National Chung-Hsing University, Taichung, Taiwan
| | - Yit-Wai Mak
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
| | - Yet-Ran Chen
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
| | - Kuo-Chen Yeh
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
- Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, National Chung-Hsing University and Academia Sinica, Taipei, Taiwan
- Graduate Institute of Biotechnology and Department of Life Sciences, National Chung-Hsing University, Taichung, Taiwan
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Shi R, Weber G, Köster J, Reza-Hajirezaei M, Zou C, Zhang F, von Wirén N. Senescence-induced iron mobilization in source leaves of barley (Hordeum vulgare) plants. THE NEW PHYTOLOGIST 2012; 195:372-383. [PMID: 22591276 DOI: 10.1111/j.1469-8137.2012.04165.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
• Retranslocation of iron (Fe) from source leaves to sinks requires soluble Fe binding forms. As much of the Fe is protein-bound and associated with the leaf nitrogen (N) status, we investigated the role of N in Fe mobilization and retranslocation under N deficiency- vs dark-induced leaf senescence. • By excluding Fe retranslocation from the apoplastic root pool, Fe concentrations in source and sink leaves from hydroponically grown barley (Hordeum vulgare) plants were determined in parallel with the concentrations of potential Fe chelators and the expression of genes involved in phytosiderophore biosynthesis. • N supply showed opposing effects on Fe pools in source leaves, inhibiting Fe export out of source leaves under N sufficiency but stimulating Fe export from source leaves under N deficiency, which partially alleviated Fe deficiency-induced chlorosis. Both triggers of leaf senescence, shading and N deficiency, enhanced NICOTIANAMINE SYNTHASE2 gene expression, soluble Fe pools in source leaves, and phytosiderophore and citrate rather than nicotianamine concentrations. • These results indicate that Fe mobilization within senescing leaves is independent of a concomitant N sink in young leaves and that phytosiderophores enhance Fe solubility in senescing source leaves, favoring subsequent Fe retranslocation.
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Affiliation(s)
- Rongli Shi
- Molecular Plant Nutrition, Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466 Gatersleben, Germany
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Günther Weber
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Bunsen-Kirchhoff-Str 11, 44139 Dortmund, Germany
| | - Jessica Köster
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Bunsen-Kirchhoff-Str 11, 44139 Dortmund, Germany
| | - Mohammad Reza-Hajirezaei
- Molecular Plant Nutrition, Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466 Gatersleben, Germany
| | - Chunqin Zou
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Fusuo Zhang
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Nicolaus von Wirén
- Molecular Plant Nutrition, Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466 Gatersleben, Germany
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14
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Nishiyama R, Kato M, Nagata S, Yanagisawa S, Yoneyama T. Identification of Zn–Nicotianamine and Fe–2′-Deoxymugineic Acid in the Phloem Sap from Rice Plants (Oryza sativa L.). ACTA ACUST UNITED AC 2012; 53:381-90. [DOI: 10.1093/pcp/pcr188] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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15
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Schuler M, Bauer P. Heavy Metals Need Assistance: The Contribution of Nicotianamine to Metal Circulation Throughout the Plant and the Arabidopsis NAS Gene Family. FRONTIERS IN PLANT SCIENCE 2011; 2:69. [PMID: 22639605 PMCID: PMC3355620 DOI: 10.3389/fpls.2011.00069] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 10/10/2011] [Indexed: 05/06/2023]
Abstract
Understanding the regulated inter- and intra-cellular metal circulation is one of the challenges in the field of metal homeostasis. Inside organisms metal ions are bound to organic ligands to prevent their uncontrolled reactivity and to increase their solubility. Nicotianamine (NA) is one of the important ligands. This non-proteinogenic amino acid is synthesized by nicotianamine synthase (NAS). NA is involved in mobilization, uptake, transport, storage, and detoxification of metals. Much of the progress in understanding NA function has been achieved by studying mutants with altered nicotianamine levels. Mild and strong Arabidopsis mutants impaired in nicotianamine synthesis have been identified and characterized, namely nas4x-1 and nas4x-2. Arabidopsis thaliana has four NAS genes. In this review, we summarize the structure and evolution of the NAS genes in the Arabidopsis genome. We summarize previous results and present novel evidence that the four NAS genes have partially overlapping functions when plants are exposed to Fe deficiency and nickel supply. We compare the phenotypes of nas4x-1 and nas4x-2 and summarize the functions of NAS genes and NA as deduced from the studies of mutant phenotypes.
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Affiliation(s)
- Mara Schuler
- Department of Biosciences–Plant Biology, Saarland UniversitySaarbrücken, Germany
| | - Petra Bauer
- Department of Biosciences–Plant Biology, Saarland UniversitySaarbrücken, Germany
- *Correspondence: Petra Bauer, Department of Biosciences–Plant Biology, Saarland University, Campus A2.4, D-66123 Saarbrücken, Germany. e-mail:
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16
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Dell'mour M, Koellensperger G, Quirino JP, Haddad PR, Stanetty C, Oburger E, Puschenreiter M, Hann S. Complexation of metals by phytosiderophores revealed by CE-ESI-MS and CE-ICP-MS. Electrophoresis 2010; 31:1201-1207. [DOI: 10.1002/elps.200900635] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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17
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Cvitanich C, Przybyłowicz WJ, Urbanski DF, Jurkiewicz AM, Mesjasz-Przybyłowicz J, Blair MW, Astudillo C, Jensen EØ, Stougaard J. Iron and ferritin accumulate in separate cellular locations in Phaseolus seeds. BMC PLANT BIOLOGY 2010; 10:26. [PMID: 20149228 PMCID: PMC2831038 DOI: 10.1186/1471-2229-10-26] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 02/11/2010] [Indexed: 05/04/2023]
Abstract
BACKGROUND Iron is an important micronutrient for all living organisms. Almost 25% of the world population is affected by iron deficiency, a leading cause of anemia. In plants, iron deficiency leads to chlorosis and reduced yield. Both animals and plants may suffer from iron deficiency when their diet or environment lacks bioavailable iron. A sustainable way to reduce iron malnutrition in humans is to develop staple crops with increased content of bioavailable iron. Knowledge of where and how iron accumulates in seeds of crop plants will increase the understanding of plant iron metabolism and will assist in the production of staples with increased bioavailable iron. RESULTS Here we reveal the distribution of iron in seeds of three Phaseolus species including thirteen genotypes of P. vulgaris, P. coccineus, and P. lunatus. We showed that high concentrations of iron accumulate in cells surrounding the provascular tissue of P. vulgaris and P. coccineus seeds. Using the Perls' Prussian blue method, we were able to detect iron in the cytoplasm of epidermal cells, cells near the epidermis, and cells surrounding the provascular tissue. In contrast, the protein ferritin that has been suggested as the major iron storage protein in legumes was only detected in the amyloplasts of the seed embryo. Using the non-destructive micro-PIXE (Particle Induced X-ray Emission) technique we show that the tissue in the proximity of the provascular bundles holds up to 500 microg g(-1) of iron, depending on the genotype. In contrast to P. vulgaris and P. coccineus, we did not observe iron accumulation in the cells surrounding the provascular tissues of P. lunatus cotyledons. A novel iron-rich genotype, NUA35, with a high concentration of iron both in the seed coat and cotyledons was bred from a cross between an Andean and a Mesoamerican genotype. CONCLUSIONS The presented results emphasize the importance of complementing research in model organisms with analysis in crop plants and they suggest that iron distribution criteria should be integrated into selection strategies for bean biofortification.
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Affiliation(s)
- Cristina Cvitanich
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
| | - Wojciech J Przybyłowicz
- Materials Research Department, iThemba LABS, Somerset West, South Africa
- on leave from: Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Kraków, Poland
| | - Dorian F Urbanski
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
| | - Anna M Jurkiewicz
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
| | | | - Matthew W Blair
- International Center for Tropical Agriculture, Cali, Colombia
| | | | - Erik Ø Jensen
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
| | - Jens Stougaard
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
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Rellán-Alvarez R, Abadía J, Alvarez-Fernández A. Formation of metal-nicotianamine complexes as affected by pH, ligand exchange with citrate and metal exchange. A study by electrospray ionization time-of-flight mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2008; 22:1553-62. [PMID: 18421700 DOI: 10.1002/rcm.3523] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Nicotianamine (NA) is considered as a key element in plant metal homeostasis. This non-proteinogenic amino acid has an optimal structure for chelation of metal ions, with six functional groups that allow octahedral coordination. The ability to chelate metals by NA is largely dependent on the pK of the resulting complex and the pH of the solution, with most metals being chelated at neutral or basic pH values. In silico calculations using pKa and pK values have predicted the occurrence of metal-NA complexes in plant fluids, but the use of soft ionization techniques (e.g. electrospray), together with high-resolution mass spectrometers (e.g. time-of-flight mass detector), can offer direct and metal-specific information on the speciation of NA in solution. We have used direct infusion electrospray ionization mass spectrometry (time-of-flight) ESI-MS(TOF) to study the complexation of Mn, Fe(II), Fe(III), Ni, Cu by NA. The pH dependence of the metal-NA complexes in ESI-MS was compared to that predicted in silico. Possible exchange reactions that may occur between Fe-NA and other metal micronutrients as Zn and Cu, as well as between Fe-NA and citrate, another possible Fe ligand candidate in plants, were studied at pH 5.5 and 7.5, values typical of the plant xylem and phloem saps. Metal-NA complexes were generally observed in the ESI-MS experiments at a pH value approximately 1-2 units lower than that predicted in silico, and this difference could be only partially explained by the estimated error, approximately 0.3 pH units, associated with measuring pH in organic solvent-containing solutions. Iron-NA complexes are less likely to participate in ligand- and metal-exchange reactions at pH 7.5 than at pH 5.5. Results support that NA may be the ligand chelating Fe at pH values usually found in phloem sap, whereas in the xylem sap NA is not likely to be involved in Fe transport, conversely to what occurs with other metals such as Cu and Ni. Some considerations that need to be addressed when studying metal complexes in plant compartments by ESI-MS are also discussed.
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Affiliation(s)
- Rubén Rellán-Alvarez
- Department of Plant Nutrition, Aula Dei Experimental Station (CSIC), P.O. Box 202, 50080 Zaragoza, Spain
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Investigation of ascorbate-mediated iron release from ferric phytosiderophores in the presence of nicotianamine. Biometals 2008; 21:503-13. [DOI: 10.1007/s10534-008-9137-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2008] [Accepted: 02/14/2008] [Indexed: 12/22/2022]
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Xuan Y, Scheuermann EB, Meda AR, Jacob P, von Wirén N, Weber G. CE of phytosiderophores and related metal species in plants. Electrophoresis 2008; 28:3507-19. [PMID: 17768721 DOI: 10.1002/elps.200700117] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Phytosiderophores (PS) and the closely related substance nicotianamine (NA) are key substances in metal uptake into graminaceous plants. Here, the CE separation of these substances and related metal species is demonstrated. In particular, the three PS 2'-deoxymugineic acid (DMA), mugineic acid (MA), and 3-epi-hydroxymugineic acid (epi-HMA), and NA, are separated using MES/Tris buffer at pH 7.3. Moreover, three Fe(III) species of the different PS are separated without any stability problems, which are often present in chromatographic analyses. Also divalent metal species of Cu, Ni, and Zn with the ligands DMA and NA are separated with the same method. By using a special, zwitterionic CE capillary, even the separation of two isomeric Fe(III) chelates with the ligand ethylenediamine-N,N'-bis(o-hydroxyphenyl)acetic acid (EDDHA) is possible (i.e., meso-Fe(III)-EDDHA and rac-Fe(III)-EDDHA), and for fast separations of NA and respective divalent and trivalent metal species, a polymer CE microchip with suppressed EOF is described. The proposed CE method is applicable to real plant samples, and enables to detect changes of metal species (Cu-DMA, Ni-NA), which are directly correlated to biological processes.
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Affiliation(s)
- Yue Xuan
- Institute for Analytical Sciences, Bunsen-Kirchoff-Strasse 11, D-44139 Dortmund, Germany
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Pelagatti P, Bacchi A, Balordi M, Caneschi A, Giannetto M, Pelizzi C, Gonsalvi L, Peruzzini M, Ugozzoli F. A Ligand-Driven Geometry Switch in Octahedral and Trigonal-Bipyramidal Iron Complexes Containing (H)PNO and PNN Ligands. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200600731] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2006; 41:1520-1531. [PMID: 17103385 DOI: 10.1002/jms.958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
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23
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Xuan Y, Scheuermann EB, Meda AR, Hayen H, von Wirén N, Weber G. Separation and identification of phytosiderophores and their metal complexes in plants by zwitterionic hydrophilic interaction liquid chromatography coupled to electrospray ionization mass spectrometry. J Chromatogr A 2006; 1136:73-81. [PMID: 17045280 DOI: 10.1016/j.chroma.2006.09.060] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 09/15/2006] [Accepted: 09/20/2006] [Indexed: 11/29/2022]
Abstract
A sensitive method for the separation of different phytosiderophores (PS) of the mugineic acid (MA) family, and the candidate ligand for intracellular metal transport in plants nicotianamine (NA), and respective metal complexes in plants by zwitterionic hydrophilic interaction liquid chromatography (ZIC-HILIC) coupled to electrospray ionization mass spectrometry (ESI-MS) is described. Separation of mugineic acid, 2'-deoxymugineic acid (DMA), 3-epi-hydroxymugineic acid (epi-HMA), nicotianamine, Fe(III)-DMA, Fe(III)-NA, M(II)-DMA, and M(II)-NA complexes (M(II)=Zn(II), Cu(II), Ni(II), and Fe(II)), was achieved within 22 min on the ZIC-HILIC column by using a gradient elution with a mobile phase consisting of ammonium acetate and acetonitrile at pH 7.3, at a flow rate of 0.15 mL/min. The on-line coupling to ESI-MS in the negative ionization mode enables the detection of these compounds in the micromol/L range, which is the relevant concentration range in real plant samples. DMA-complexes of Fe(III), Zn, and Cu in wheat root, and an NA-complex of Ni in Arabidopsis were detected and identified by the proposed method. Even in the case of partial coelution of some divalent metal complexes, the identification is possible by their distinct mass spectra. The stability of metal complexes during separation was checked by injecting ethylenediaminetetraacetic acid (EDTA) after each run of metal-phytosiderophore complexes. Good stability of divalent-phytosiderophores, except for Fe(II)-complexes, was observed. During gradient separation, Fe(III)-complexes are partly dissociated (<20%), but a good sensitivity of Fe(III)-DMA in real plant samples is still achieved. In order to avoid instability problems with the separation of Fe-complexes, an isocratic separation is proposed, which allows the separation of ferrous and ferric complexes in 2 min.
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Affiliation(s)
- Yue Xuan
- ISAS - Institute for Analytical Sciences, Bunsen-Kirchhoff-Strasse 11, D-44139 Dortmund, Germany
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