Uptake, translocation and transformation of arsenate and arsenite in sunflower (Helianthus annuus): formation of arsenic-phytochelatin complexes during exposure to high arsenic concentrations

Andrea Raab, H. Schat, Andrew Alexander Meharg, Jorg Feldmann

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216 Citations (Scopus)

Abstract

The aim of the study was to determine the time-dependent formation of arsenic-phytochelatin (As-PC) complexes in the roots, stems and leaves of an arsenic-nontolerant plant (Helianthus annuus) during exposure to 66 mol l(-1) arsenite (As-(III)) or arsenate (As-(V)).

We used our previously developed method of simultaneous element-specific (inductively coupled plasma mass spectrometry, ICP-MS) and molecular-specific (electrospray-ionization mass spectrometry, ES-MS) detection systems interfaced with a suitable chromatographic column and eluent conditions, which enabled us to identify and quantify As-PC complexes directly.

Roots of As-exposed H. annuus contained up to 14 different arsenic species, including the complex of arsenite with two (gamma-Glu-Cys)(2)-Gly molecules [As-(III)-(PC2)(2)], the newly identified monomethylarsonic phytochelatin-2 or (gamma-Glu-Cys)(2)-Gly CH3As (MA((III))-PC2) and at least eight not yet identified species. The complex of arsenite with (gamma-Glu-Cys)(3)-Gly (As-(III)-PC3) and the complex of arsenite with glutathione (GSH) and (gamma-Glu-Cys)(2)-Gly (GS-As-(III)-PC2) were present in all samples (roots, stems and leaves) taken from plants exposed to As. The GS-As-(III)-PC2 complex was the dominant complex after 1 h of exposure. As-(III)-PC3 became the predominant As-PC complex after 3 h, binding up to 40% of the As present in the exposed plants.

No As-PC complexes were found in sap (mainly xylem sap from the root system), in contrast to roots, stems and leaves, which is unequivocal evidence that As-PC complexes are not involved in the translocation of As from root to leaves of H. annuus.

Original languageEnglish
Pages (from-to)551-558
Number of pages7
JournalNew Phytologist
Volume168
DOIs
Publication statusPublished - Jun 2005

Keywords

  • arsenic
  • arsenic-phytochelatin (As-PC) complex
  • arsenic speciation
  • Helianthus annuus (sunflower)
  • phytochelatin
  • HEAVY-METAL DETOXIFICATION
  • HOLCUS-LANATUS
  • GLUTATHIONE
  • CADMIUM
  • PLANTS
  • ACCUMULATION
  • ARABIDOPSIS
  • EXCRETION
  • TOXICITY
  • ROLES

Cite this

@article{105a88192fc146bf9722f2bdc7169da9,
title = "Uptake, translocation and transformation of arsenate and arsenite in sunflower (Helianthus annuus): formation of arsenic-phytochelatin complexes during exposure to high arsenic concentrations",
abstract = "The aim of the study was to determine the time-dependent formation of arsenic-phytochelatin (As-PC) complexes in the roots, stems and leaves of an arsenic-nontolerant plant (Helianthus annuus) during exposure to 66 mol l(-1) arsenite (As-(III)) or arsenate (As-(V)).We used our previously developed method of simultaneous element-specific (inductively coupled plasma mass spectrometry, ICP-MS) and molecular-specific (electrospray-ionization mass spectrometry, ES-MS) detection systems interfaced with a suitable chromatographic column and eluent conditions, which enabled us to identify and quantify As-PC complexes directly.Roots of As-exposed H. annuus contained up to 14 different arsenic species, including the complex of arsenite with two (gamma-Glu-Cys)(2)-Gly molecules [As-(III)-(PC2)(2)], the newly identified monomethylarsonic phytochelatin-2 or (gamma-Glu-Cys)(2)-Gly CH3As (MA((III))-PC2) and at least eight not yet identified species. The complex of arsenite with (gamma-Glu-Cys)(3)-Gly (As-(III)-PC3) and the complex of arsenite with glutathione (GSH) and (gamma-Glu-Cys)(2)-Gly (GS-As-(III)-PC2) were present in all samples (roots, stems and leaves) taken from plants exposed to As. The GS-As-(III)-PC2 complex was the dominant complex after 1 h of exposure. As-(III)-PC3 became the predominant As-PC complex after 3 h, binding up to 40{\%} of the As present in the exposed plants.No As-PC complexes were found in sap (mainly xylem sap from the root system), in contrast to roots, stems and leaves, which is unequivocal evidence that As-PC complexes are not involved in the translocation of As from root to leaves of H. annuus.",
keywords = "arsenic, arsenic-phytochelatin (As-PC) complex, arsenic speciation, Helianthus annuus (sunflower), phytochelatin, HEAVY-METAL DETOXIFICATION, HOLCUS-LANATUS, GLUTATHIONE, CADMIUM, PLANTS, ACCUMULATION, ARABIDOPSIS, EXCRETION, TOXICITY, ROLES",
author = "Andrea Raab and H. Schat and Meharg, {Andrew Alexander} and Jorg Feldmann",
year = "2005",
month = "6",
doi = "10.1111/j.1469-8137.2005.01519.x",
language = "English",
volume = "168",
pages = "551--558",
journal = "New Phytologist",
issn = "0028-646X",
publisher = "Wiley/Blackwell (10.1111)",

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TY - JOUR

T1 - Uptake, translocation and transformation of arsenate and arsenite in sunflower (Helianthus annuus): formation of arsenic-phytochelatin complexes during exposure to high arsenic concentrations

AU - Raab, Andrea

AU - Schat, H.

AU - Meharg, Andrew Alexander

AU - Feldmann, Jorg

PY - 2005/6

Y1 - 2005/6

N2 - The aim of the study was to determine the time-dependent formation of arsenic-phytochelatin (As-PC) complexes in the roots, stems and leaves of an arsenic-nontolerant plant (Helianthus annuus) during exposure to 66 mol l(-1) arsenite (As-(III)) or arsenate (As-(V)).We used our previously developed method of simultaneous element-specific (inductively coupled plasma mass spectrometry, ICP-MS) and molecular-specific (electrospray-ionization mass spectrometry, ES-MS) detection systems interfaced with a suitable chromatographic column and eluent conditions, which enabled us to identify and quantify As-PC complexes directly.Roots of As-exposed H. annuus contained up to 14 different arsenic species, including the complex of arsenite with two (gamma-Glu-Cys)(2)-Gly molecules [As-(III)-(PC2)(2)], the newly identified monomethylarsonic phytochelatin-2 or (gamma-Glu-Cys)(2)-Gly CH3As (MA((III))-PC2) and at least eight not yet identified species. The complex of arsenite with (gamma-Glu-Cys)(3)-Gly (As-(III)-PC3) and the complex of arsenite with glutathione (GSH) and (gamma-Glu-Cys)(2)-Gly (GS-As-(III)-PC2) were present in all samples (roots, stems and leaves) taken from plants exposed to As. The GS-As-(III)-PC2 complex was the dominant complex after 1 h of exposure. As-(III)-PC3 became the predominant As-PC complex after 3 h, binding up to 40% of the As present in the exposed plants.No As-PC complexes were found in sap (mainly xylem sap from the root system), in contrast to roots, stems and leaves, which is unequivocal evidence that As-PC complexes are not involved in the translocation of As from root to leaves of H. annuus.

AB - The aim of the study was to determine the time-dependent formation of arsenic-phytochelatin (As-PC) complexes in the roots, stems and leaves of an arsenic-nontolerant plant (Helianthus annuus) during exposure to 66 mol l(-1) arsenite (As-(III)) or arsenate (As-(V)).We used our previously developed method of simultaneous element-specific (inductively coupled plasma mass spectrometry, ICP-MS) and molecular-specific (electrospray-ionization mass spectrometry, ES-MS) detection systems interfaced with a suitable chromatographic column and eluent conditions, which enabled us to identify and quantify As-PC complexes directly.Roots of As-exposed H. annuus contained up to 14 different arsenic species, including the complex of arsenite with two (gamma-Glu-Cys)(2)-Gly molecules [As-(III)-(PC2)(2)], the newly identified monomethylarsonic phytochelatin-2 or (gamma-Glu-Cys)(2)-Gly CH3As (MA((III))-PC2) and at least eight not yet identified species. The complex of arsenite with (gamma-Glu-Cys)(3)-Gly (As-(III)-PC3) and the complex of arsenite with glutathione (GSH) and (gamma-Glu-Cys)(2)-Gly (GS-As-(III)-PC2) were present in all samples (roots, stems and leaves) taken from plants exposed to As. The GS-As-(III)-PC2 complex was the dominant complex after 1 h of exposure. As-(III)-PC3 became the predominant As-PC complex after 3 h, binding up to 40% of the As present in the exposed plants.No As-PC complexes were found in sap (mainly xylem sap from the root system), in contrast to roots, stems and leaves, which is unequivocal evidence that As-PC complexes are not involved in the translocation of As from root to leaves of H. annuus.

KW - arsenic

KW - arsenic-phytochelatin (As-PC) complex

KW - arsenic speciation

KW - Helianthus annuus (sunflower)

KW - phytochelatin

KW - HEAVY-METAL DETOXIFICATION

KW - HOLCUS-LANATUS

KW - GLUTATHIONE

KW - CADMIUM

KW - PLANTS

KW - ACCUMULATION

KW - ARABIDOPSIS

KW - EXCRETION

KW - TOXICITY

KW - ROLES

U2 - 10.1111/j.1469-8137.2005.01519.x

DO - 10.1111/j.1469-8137.2005.01519.x

M3 - Article

VL - 168

SP - 551

EP - 558

JO - New Phytologist

JF - New Phytologist

SN - 0028-646X

ER -