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Tóth A, Sajdik K, Gyurcsik B, Nafaee ZH, Wéber E, Kele Z, Christensen NJ, Schell J, Correia JG, Sigfridsson Clauss KGV, Pittkowski RK, Thulstrup PW, Hemmingsen L, Jancsó A. As III Selectively Induces a Disorder-to-Order Transition in the Metalloid Binding Region of the AfArsR Protein. J Am Chem Soc 2024; 146:17009-17022. [PMID: 38820242 PMCID: PMC11212059 DOI: 10.1021/jacs.3c11665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 05/22/2024] [Accepted: 05/23/2024] [Indexed: 06/02/2024]
Abstract
Arsenic is highly toxic and a significant threat to human health, but certain bacteria have developed defense mechanisms initiated by AsIII binding to AsIII-sensing proteins of the ArsR family. The transcriptional regulator AfArsR responds to AsIII and SbIII by coordinating the metalloids with three cysteines, located in a short sequence of the same monomer chain. Here, we characterize the binding of AsIII and HgII to a model peptide encompassing this fragment of the protein via solution equilibrium and spectroscopic/spectrometric techniques (pH potentiometry, UV, CD, NMR, PAC, EXAFS, and ESI-MS) combined with DFT calculations and MD simulations. Coordination of AsIII changes the peptide structure from a random-coil to a well-defined structure of the complex. A trigonal pyramidal AsS3 binding site is formed with almost exactly the same structure as observed in the crystal structure of the native protein, implying that the peptide possesses all of the features required to mimic the AsIII recognition and response selectivity of AfArsR. Contrary to this, binding of HgII to the peptide does not lead to a well-defined structure of the peptide, and the atoms near the metal binding site are displaced and reoriented in the HgII model. Our model study suggests that structural organization of the metal site by the inducer ion is a key element in the mechanism of the metalloid-selective recognition of this protein.
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Affiliation(s)
- Annamária Tóth
- Department
of Molecular and Analytical Chemistry, University
of Szeged, Dóm
tér 7-8, H-6720 Szeged, Hungary
| | - Kadosa Sajdik
- Department
of Molecular and Analytical Chemistry, University
of Szeged, Dóm
tér 7-8, H-6720 Szeged, Hungary
| | - Béla Gyurcsik
- Department
of Molecular and Analytical Chemistry, University
of Szeged, Dóm
tér 7-8, H-6720 Szeged, Hungary
| | - Zeyad H. Nafaee
- Department
of Molecular and Analytical Chemistry, University
of Szeged, Dóm
tér 7-8, H-6720 Szeged, Hungary
| | - Edit Wéber
- Department
of Medical Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary
- HUN-REN-SZTE
Biomimetic Systems Research Group, Dóm tér 8, H-6720 Szeged, Hungary
| | - Zoltan Kele
- Department
of Medical Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary
| | - Niels Johan Christensen
- Department
of Chemistry, Faculty of Science, University
of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Juliana Schell
- Institute
for Materials Science and Center for Nanointegration Duisburg-Essen
(CENIDE), University of Duisburg-Essen, 45141 Essen, Germany
- European
Organization for Nuclear Research (CERN), CH-1211 Geneva, Switzerland
| | - Joao Guilherme Correia
- Centro de
Cięncias e Tecnologias Nucleares, Departamento de Engenharia
e Cięncias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, 2695-066 Bobadela LRS, Portugal
- European
Organization for Nuclear Research (CERN), CH-1211 Geneva, Switzerland
| | | | - Rebecca K. Pittkowski
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Kobenhavn Ø, Denmark
| | - Peter Waaben Thulstrup
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Kobenhavn Ø, Denmark
| | - Lars Hemmingsen
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Kobenhavn Ø, Denmark
| | - Attila Jancsó
- Department
of Molecular and Analytical Chemistry, University
of Szeged, Dóm
tér 7-8, H-6720 Szeged, Hungary
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2
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Carrall JA, Lie W, Lambert JM, Harris HH, Lai B, Dillon CT. Optimizing Arsenic Therapy by Selectively Targeting Leukemia Cells. J Med Chem 2023; 66:12101-12114. [PMID: 37594965 DOI: 10.1021/acs.jmedchem.3c00676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/20/2023]
Abstract
Arsenic, in the simple form of arsenic trioxide, is currently marketed for the treatment of acute promyelocytic leukemia. Due to the multifaceted mechanisms of action of arsenic, it has also shown promise in other types of leukemias but is hindered by its toxic effects toward normal cells. This research has aimed to determine whether tumor-homing peptide complexes of arsenic can be designed and developed to strategically target specific cancers. The end goal is to achieve dose reduction and decreased side effects of the resultant arsenic therapeutic agent. In this article, we present the synthesis, characterization, and stability studies of a new class of As-peptide complexes designed to target leukemia. In vitro biological studies of the most stable complex show 1000 times greater toxicity toward leukemia cells over human blood cells, indicating potential for progression to in vivo studies.
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Affiliation(s)
- Judith A Carrall
- School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong 2522, New South Wales, Australia
| | - Wilford Lie
- School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong 2522, New South Wales, Australia
| | - Jacob M Lambert
- School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong 2522, New South Wales, Australia
- Molecular Horizons, University of Wollongong, Wollongong 2522, New South Wales, Australia
| | - Hugh H Harris
- School of Physical Sciences, The University of Adelaide, Adelaide 5005, South Australia, Australia
| | - Barry Lai
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont 60439, Illinois, United States
| | - Carolyn T Dillon
- School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong 2522, New South Wales, Australia
- Molecular Horizons, University of Wollongong, Wollongong 2522, New South Wales, Australia
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3
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Lashani E, Amoozegar MA, Turner RJ, Moghimi H. Use of Microbial Consortia in Bioremediation of Metalloid Polluted Environments. Microorganisms 2023; 11:microorganisms11040891. [PMID: 37110315 PMCID: PMC10143001 DOI: 10.3390/microorganisms11040891] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 03/08/2023] [Accepted: 03/13/2023] [Indexed: 03/31/2023] Open
Abstract
Metalloids are released into the environment due to the erosion of the rocks or anthropogenic activities, causing problems for human health in different world regions. Meanwhile, microorganisms with different mechanisms to tolerate and detoxify metalloid contaminants have an essential role in reducing risks. In this review, we first define metalloids and bioremediation methods and examine the ecology and biodiversity of microorganisms in areas contaminated with these metalloids. Then we studied the genes and proteins involved in the tolerance, transport, uptake, and reduction of these metalloids. Most of these studies focused on a single metalloid and co-contamination of multiple pollutants were poorly discussed in the literature. Furthermore, microbial communication within consortia was rarely explored. Finally, we summarized the microbial relationships between microorganisms in consortia and biofilms to remove one or more contaminants. Therefore, this review article contains valuable information about microbial consortia and their mechanisms in the bioremediation of metalloids.
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Affiliation(s)
- Elham Lashani
- Extremophiles Laboratory, Department of Microbiology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, Tehran 14178-64411, Iran;
| | - Mohammad Ali Amoozegar
- Extremophiles Laboratory, Department of Microbiology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, Tehran 14178-64411, Iran;
- Correspondence: (M.A.A.); (H.M.); Tel.: +98-21-66415495 (H.M.)
| | - Raymond J. Turner
- Microbial Biochemistry Laboratory, Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, AB T2N 1N4, Canada;
| | - Hamid Moghimi
- Department of Microbiology, School of Biology, College of Science, University of Tehran, Tehran 14178-64411, Iran
- Correspondence: (M.A.A.); (H.M.); Tel.: +98-21-66415495 (H.M.)
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Speer RM, Zhou X, Volk LB, Liu KJ, Hudson LG. Arsenic and cancer: Evidence and mechanisms. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2022; 96:151-202. [PMID: 36858772 DOI: 10.1016/bs.apha.2022.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Arsenic is a potent carcinogen and poses a significant health concern worldwide. Exposure occurs through ingestion of drinking water and contaminated foods and through inhalation due to pollution. Epidemiological evidence shows arsenic induces cancers of the skin, lung, liver, and bladder among other tissues. While studies in animal and cell culture models support arsenic as a carcinogen, the mechanisms of arsenic carcinogenesis are not fully understood. Arsenic carcinogenesis is a complex process due its ability to be metabolized and because of the many cellular pathways it targets in the cell. Arsenic metabolism and the multiple forms of arsenic play distinct roles in its toxicity and contribute differently to carcinogenic endpoints, and thus must be considered. Arsenic generates reactive oxygen species increasing oxidative stress and damaging DNA and other macromolecules. Concurrently, arsenic inhibits DNA repair, modifies epigenetic regulation of gene expression, and targets protein function due its ability to replace zinc in select proteins. While these mechanisms contribute to arsenic carcinogenesis, there remain significant gaps in understanding the complex nature of arsenic cancers. In the future improving models available for arsenic cancer research and the use of arsenic induced human tumors will bridge some of these gaps in understanding arsenic driven cancers.
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Affiliation(s)
- Rachel M Speer
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, United States
| | - Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, United States
| | - Lindsay B Volk
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, United States
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, United States; Stony Brook Cancer Center, Renaissance School of Medicine, State University of New York Stony Brook, Stony Brook, NY, United States.
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, United States
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Zhou X, Speer RM, Volk L, Hudson LG, Liu KJ. Arsenic co-carcinogenesis: Inhibition of DNA repair and interaction with zinc finger proteins. Semin Cancer Biol 2021; 76:86-98. [PMID: 33984503 PMCID: PMC8578584 DOI: 10.1016/j.semcancer.2021.05.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/05/2021] [Accepted: 05/06/2021] [Indexed: 12/17/2022]
Abstract
Arsenic is widely present in the environment and is associated with various population health risks including cancers. Arsenic exposure at environmentally relevant levels enhances the mutagenic effect of other carcinogens such as ultraviolet radiation. Investigation on the molecular mechanisms could inform the prevention and intervention strategies of arsenic carcinogenesis and co-carcinogenesis. Arsenic inhibition of DNA repair has been demonstrated to be an important mechanism, and certain DNA repair proteins have been identified to be extremely sensitive to arsenic exposure. This review will summarize the recent advances in understanding the mechanisms of arsenic carcinogenesis and co-carcinogenesis, including DNA damage induction and ROS generation, particularly how arsenic inhibits DNA repair through an integrated molecular mechanism which includes its interactions with sensitive zinc finger DNA repair proteins.
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Affiliation(s)
- Xixi Zhou
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Rachel M Speer
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Lindsay Volk
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA.
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA.
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6
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Hirano S. Biotransformation of arsenic and toxicological implication of arsenic metabolites. Arch Toxicol 2020; 94:2587-2601. [PMID: 32435915 DOI: 10.1007/s00204-020-02772-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 05/04/2020] [Indexed: 12/13/2022]
Abstract
Arsenic is a well-known environmental carcinogen and chronic exposure to arsenic through drinking water has been reported to cause skin, bladder and lung cancers, with arsenic metabolites being implicated in the pathogenesis. In contrast, arsenic trioxide (As2O3) is an effective therapeutic agent for the treatment of acute promyelocytic leukemia, in which the binding of arsenite (iAsIII) to promyelocytic leukemia (PML) protein is the proposed initial step. These findings on the two-edged sword characteristics of arsenic suggest that after entry into cells, arsenic reaches the nucleus and triggers various nuclear events. Arsenic is reduced, conjugated with glutathione, and methylated in the cytosol. These biotransformations, including the production of reactive metabolic intermediates, appear to determine the intracellular dynamics, target organs, and biological functions of arsenic.
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Affiliation(s)
- Seishiro Hirano
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
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7
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Banerjee M, Ferragut Cardoso AP, Lykoudi A, Wilkey DW, Pan J, Watson WH, Garbett NC, Rai SN, Merchant ML, States JC. Arsenite Exposure Displaces Zinc from ZRANB2 Leading to Altered Splicing. Chem Res Toxicol 2020; 33:1403-1417. [PMID: 32274925 DOI: 10.1021/acs.chemrestox.9b00515] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Exposure to arsenic, a class I carcinogen, affects 200 million people globally. Skin is the major target organ, but the molecular etiology of arsenic-induced skin carcinogenesis remains unclear. Arsenite (As3+)-induced disruption of alternative splicing could be involved, but the mechanism is unknown. Zinc finger proteins play key roles in alternative splicing. As3+ can displace zinc (Zn2+) from C3H1 and C4 zinc finger motifs (zfm's), affecting protein function. ZRANB2, an alternative splicing regulator with two C4 zfm's integral to its structure and splicing function, was chosen as a candidate for this study. We hypothesized that As3+ could displace Zn2+ from ZRANB2, altering its structure, expression, and splicing function. As3+/Zn2+ binding and mutual displacement experiments were performed with synthetic apo-peptides corresponding to each ZRANB2 zfm, employing a combination of intrinsic fluorescence, ultraviolet spectrophotometry, zinc colorimetric assay, and liquid chromatography-tandem mass spectrometry. ZRANB2 expression in HaCaT cells acutely exposed to As3+ (0 or 5 μM, 0-72 h; or 0-5 μM, 6 h) was examined by RT-qPCR and immunoblotting. ZRANB2-dependent splicing of TRA2B mRNA, a known ZRANB2 target, was monitored by reverse transcription-polymerase chain reaction. As3+ bound to, as well as displaced Zn2+ from, each zfm. Also, Zn2+ displaced As3+ from As3+-bound zfm's acutely, albeit transiently. As3+ exposure induced ZRANB2 protein expression between 3 and 24 h and at all exposures tested but not ZRANB2 mRNA expression. ZRANB2-directed TRA2B splicing was impaired between 3 and 24 h post-exposure. Furthermore, ZRANB2 splicing function was also compromised at all As3+ exposures, starting at 100 nm. We conclude that As3+ exposure displaces Zn2+ from ZRANB2 zfm's, changing its structure and compromising splicing of its targets, and increases ZRANB2 protein expression as a homeostatic response both at environmental/toxicological exposures and therapeutically relevant doses.
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Affiliation(s)
- Mayukh Banerjee
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States
| | - Ana P Ferragut Cardoso
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States
| | - Angeliki Lykoudi
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States
| | - Daniel W Wilkey
- Division of Nephrology & Hypertension, Department of Medicine, University of Louisville, Louisville, Kentucky 40202, United States
| | - Jianmin Pan
- Biostatistics and Bioinformatics Facility, James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky 40202, United States
| | - Walter H Watson
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States.,Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Louisville, Louisville, Kentucky 40202, United States
| | - Nichola C Garbett
- Division of Medical Oncology and Hematology, Department of Medicine, University of Louisville, Louisville, Kentucky 40202, United States.,James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky 40202, United States
| | - Shesh N Rai
- Biostatistics and Bioinformatics Facility, James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky 40202, United States.,Department of Bioinformatics and Biostatistics, University of Louisville, Louisville, Kentucky 40202, United States
| | - Michael L Merchant
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States.,Division of Nephrology & Hypertension, Department of Medicine, University of Louisville, Louisville, Kentucky 40202, United States
| | - J Christopher States
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States
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8
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Kluska K, Adamczyk J, Krężel A. Metal binding properties, stability and reactivity of zinc fingers. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.04.009] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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9
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Szekeres LI, Gyurcsik B, Kiss T, Kele Z, Jancsó A. Interaction of Arsenous Acid with the Dithiol-Type Chelator British Anti-Lewisite (BAL): Structure and Stability of Species Formed in an Unexpectedly Complex System. Inorg Chem 2018; 57:7191-7200. [PMID: 29856616 DOI: 10.1021/acs.inorgchem.8b00894] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
British anti-Lewisite (2,3-dimerkaptopropan-1-ol, dimercaprol, BAL) is one of the best-known chelator-type therapeutic agents against toxic metal ions and metalloids, especially arsenicals. Surprisingly, the mechanisms of action at the molecular level, as well as the coordination features of this traditional drug toward various arsenicals, are still poorly revealed. The present study on the interaction of arsenous acid (H3AsO3) with BAL, involving UV and NMR titrations, electrospray ionization mass spectrometry, and 2D NMR experiments combined with MP2 calculations, demonstrates that the reaction of H3AsO3 with BAL at pH = 7.0 results in a more complex speciation than was assumed before. The three reactive hydroxyl groups of H3AsO3 allow for interaction with three thiol moieties via condensation reaction, leading to the observed AsBAL2 and As2BAL3 complexes besides the AsBAL species. This indicates the strong propensity of inorganic As(III) to saturate its coordination sphere with thiolate groups. The alcoholic hydroxyl group of the ligand may also directly bind to As(III) in AsBAL. Compared to dithiothreitol or dithioeritritol, the preference of BAL to form complexes with such a tridentate binding mode is much lower owing to the more strained bridged bicyclic structure with an αAsSC < 90° bond angle and an unfavorable condensed boat-type six-membered ring. On the basis of the NMR data, the predominating, bidentately bound AsBAL species, including a five-membered chelate ring, exists in rapidly interconverting envelope forms of E and Z stereoisomers. The conditional stability constants calculated for the three macrospecies from a series of UV data [log βpH=7.0 = 6.95 (AsBAL), 11.56 (AsBAL2), and 22.73 (As2BAL3)] reflect that BAL is still the most efficient, known, dithiol-type chelator of H3AsO3.
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Affiliation(s)
- Levente I Szekeres
- Department of Inorganic and Analytical Chemistry , University of Szeged , Dóm tér 7 , Szeged H-6720 , Hungary
| | - Béla Gyurcsik
- Department of Inorganic and Analytical Chemistry , University of Szeged , Dóm tér 7 , Szeged H-6720 , Hungary
| | - Tamás Kiss
- Department of Inorganic and Analytical Chemistry , University of Szeged , Dóm tér 7 , Szeged H-6720 , Hungary
| | - Zoltán Kele
- Department of Medical Chemistry , University of Szeged , Dóm tér 8 , Szeged H-6720 , Hungary
| | - Attila Jancsó
- Department of Inorganic and Analytical Chemistry , University of Szeged , Dóm tér 7 , Szeged H-6720 , Hungary
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10
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Drzewiecka K, Gąsecka M, Rutkowski P, Magdziak Z, Goliński P, Mleczek M. Arsenic forms and their combinations induce differences in phenolic accumulation in Ulmus laevis Pall. JOURNAL OF PLANT PHYSIOLOGY 2018; 220:34-42. [PMID: 29145070 DOI: 10.1016/j.jplph.2017.09.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 09/26/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
Total phenolics and the profile of phenolic acids and flavonoids were investigated in the roots and leaves of Ulmus laevis cultured on the medium with inorganic and organic arsenic - As(III), As(V) and DMA(V) at 0.06mM and their equimolar combinations. Further, the accumulation of salicylic acid (free and glucoside-bound) and lipid oxidation were assayed following a three-month long experiment. As treatment caused elevated production of phenolics, which was higher in photosynthetic tissue than in roots for all As forms and their combinations, and their overall content was correlated with the accumulation of organic As in roots and As(III) in leaves. The accumulation of organic As strongly induced shikimate-derived protocatechiuc acid in roots. Contrary to this, shikimate-derived phenolics (protocatechuic, gallic acids and 4-HBA) were suppressed in leaves, while the accumulation of C6C3 acids (caffeic, p-coumaric and chlorogenic) was stimulated by As(V) application. Surprisingly, these acids were not detected in the leaves of As(III)-treated plants, and mutually applied As(III) and DMA(V) reduced their content. DMA(V) negatively influenced the level of salicylic acid and its storage mechanism and this effect correlated with elevated MDA content in leaves. Quercetin accumulation was observed in both organs (mainly leaves) of DMA(V)-treated plants thereby proving its function in defensive response of Ulmus laevis to organic forms of As.
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Affiliation(s)
- Kinga Drzewiecka
- Poznań University of Life Sciences, Department of Chemistry, Wojska Polskiego 75, 60-625 Poznań, Poland
| | - Monika Gąsecka
- Poznań University of Life Sciences, Department of Chemistry, Wojska Polskiego 75, 60-625 Poznań, Poland
| | - Paweł Rutkowski
- Poznań University of Life Sciences, Department of Forest Sites and Ecology, Wojska Polskiego 71F, 60-625 Poznań, Poland
| | - Zuzanna Magdziak
- Poznań University of Life Sciences, Department of Chemistry, Wojska Polskiego 75, 60-625 Poznań, Poland
| | - Piotr Goliński
- Poznań University of Life Sciences, Department of Chemistry, Wojska Polskiego 75, 60-625 Poznań, Poland
| | - Mirosław Mleczek
- Poznań University of Life Sciences, Department of Chemistry, Wojska Polskiego 75, 60-625 Poznań, Poland.
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11
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Sun HJ, Xiang P, Luo J, Hong H, Lin H, Li HB, Ma LQ. Mechanisms of arsenic disruption on gonadal, adrenal and thyroid endocrine systems in humans: A review. ENVIRONMENT INTERNATIONAL 2016; 95:61-68. [PMID: 27502899 DOI: 10.1016/j.envint.2016.07.020] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 07/28/2016] [Accepted: 07/29/2016] [Indexed: 06/06/2023]
Abstract
Due to its toxicity as a carcinogen and wide distribution in the environment, arsenic (As) exposure in humans is of public concern globally. Many studies have manifested that As exposure induces cancers besides pathological effects in humans. Animal studies showed that chronic As exposure induces serious neurological effects. Based on recent studies, researchers proposed that As, including arsenate (AsV) and arsenite (AsIII), is also an endocrine disruptor. This review discusses the mechanisms of As toxicity on three endocrine systems including gonadal, adrenal and thyroid endocrine systems. Arsenic methylation and oxidative stress are responsible for As-induced disorders of endocrine systems, however, strong binding of AsIII to thiols also play an important role. Some studies showed AsV toxicity on endocrine systems, but mechanistic investigation is lacking. Research is needed to look into their toxicity mechanisms to help cure the illnesses caused by As-induced endocrine system disorders.
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Affiliation(s)
- Hong-Jie Sun
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China; College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Ping Xiang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China
| | - Jun Luo
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China
| | - Huachang Hong
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Hongjun Lin
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Hong-Bo Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China.
| | - Lena Q Ma
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China; Soil and Water Science Department, University of Florida, Gainesville, FL 32611, USA.
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12
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Park JH, Han YS, Seong HJ, Ahn JS, Nam IH. Arsenic uptake and speciation in Arabidopsis thaliana under hydroponic conditions. CHEMOSPHERE 2016; 154:283-288. [PMID: 27058920 DOI: 10.1016/j.chemosphere.2016.03.126] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 03/17/2016] [Accepted: 03/25/2016] [Indexed: 06/05/2023]
Abstract
Arsenic (As) uptake and species in Arabidopsis thaliana were evaluated under hydroponic conditions. Plant nutrient solutions were treated with arsenite [As(III)] or arsenate [As(V)], and aqueous As speciation was conducted using a solid phase extraction (SPE) cartridge. Arabidopsis reduced As(V) to As(III) in the nutrient solution, possibly due to root exudates such as organic acids or the efflux of As(III) from plant roots after in vivo reduction of As(V) to As(III). Arsenic uptake by Arabidopsis was associated with increased levels of Ca and Fe, and decreased levels of K in plant tissues. Arsenic in Arabidopsis mainly occurred as As(III), which was coordinated with oxygen and sulfur based on XANES and EXAFS results. The existence of As(III)O and As(III)S in EXAFS indicates partial biotransformation of As(III)O to a sulfur-coordinated form because of limited amount of glutathione in plants. Further understanding the mechanism of As biotransformation in Arabidopsis may help to develop measures that can mitigate As toxicity via genetic engineering.
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Affiliation(s)
- Jin Hee Park
- Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources, 124 Gwahang-no, Yuseong-gu, Daejeon, 34132, Republic of Korea
| | - Young-Soo Han
- Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources, 124 Gwahang-no, Yuseong-gu, Daejeon, 34132, Republic of Korea
| | - Hye Jin Seong
- Department of Energy & Resources Engineering, Korea Maritime and Ocean University, 727 Taejong-ro, Yeongdo-Gu, Busan, 49112, Republic of Korea
| | - Joo Sung Ahn
- Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources, 124 Gwahang-no, Yuseong-gu, Daejeon, 34132, Republic of Korea
| | - In-Hyun Nam
- Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources, 124 Gwahang-no, Yuseong-gu, Daejeon, 34132, Republic of Korea.
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13
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Hajeb P, Sloth JJ, Shakibazadeh S, Mahyudin NA, Afsah-Hejri L. Toxic Elements in Food: Occurrence, Binding, and Reduction Approaches. Compr Rev Food Sci Food Saf 2014; 13:457-472. [DOI: 10.1111/1541-4337.12068] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 02/14/2014] [Indexed: 02/03/2023]
Affiliation(s)
- P. Hajeb
- Food Safety Research Centre (FOSREC); Faculty of Food Science and Technology; Universiti Putra Malaysia, 43400, UPM, Serdang; Selangor Malaysia
| | - J. J. Sloth
- National Food Inst; Technical Univ. of Denmark, Mørkhøj Bygade 19; DK-2860 Søborg Denmark
| | - Sh. Shakibazadeh
- Dept. of Aquaculture; Faculty of Agriculture; Universiti Putra Malaysia, 43400, UPM Serdang; Selangor Malaysia
| | - N. A. Mahyudin
- Food Safety Research Centre (FOSREC); Faculty of Food Science and Technology; Universiti Putra Malaysia, 43400, UPM, Serdang; Selangor Malaysia
| | - L. Afsah-Hejri
- Food Safety Research Centre (FOSREC); Faculty of Food Science and Technology; Universiti Putra Malaysia, 43400, UPM, Serdang; Selangor Malaysia
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14
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Zhao L, Wang Z, Xi Z, Xu D, Chen S, Liu Y. The Reaction of Arsenite with Proteins Relies on Solution Conditions. Inorg Chem 2014; 53:3054-61. [DOI: 10.1021/ic402891t] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Linhong Zhao
- CAS Key
Laboratory of Soft Matter Chemistry, CAS High Magnetic Field Laboratory,
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026 China
| | - Zhen Wang
- CAS Key
Laboratory of Soft Matter Chemistry, CAS High Magnetic Field Laboratory,
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026 China
| | - Zhaoyong Xi
- CAS Key
Laboratory of Soft Matter Chemistry, CAS High Magnetic Field Laboratory,
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026 China
| | - Dechen Xu
- CAS Key
Laboratory of Soft Matter Chemistry, CAS High Magnetic Field Laboratory,
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026 China
| | - Siming Chen
- CAS Key
Laboratory of Soft Matter Chemistry, CAS High Magnetic Field Laboratory,
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026 China
| | - Yangzhong Liu
- CAS Key
Laboratory of Soft Matter Chemistry, CAS High Magnetic Field Laboratory,
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026 China
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15
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Liang X, Drueckhammer DG. Arsinous acid as a thiol binding group: potential cysteine peptide tagging functionality that binds a single thiol. NEW J CHEM 2014. [DOI: 10.1039/c3nj01462b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A simple aryl arsinous acid (ArAs(CH3)OH) was prepared byorthomercuration ofp-cresol followed by Pd-catalyzed reaction with methylarsenic dibromide, purification as the mercaptoethanol adduct, and deprotection using a silver salt.
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Affiliation(s)
- Xiaofei Liang
- Department of Chemistry
- Stony Brook University
- Stony Brook, USA
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16
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Affiliation(s)
- Shengwen Shen
- Department
of Laboratory Medicine
and Pathology, 10-102 Clinical Sciences Building, University
of Alberta, Edmonton, Alberta, Canada, T6G 2G3
| | - Xing-Fang Li
- Department
of Laboratory Medicine
and Pathology, 10-102 Clinical Sciences Building, University
of Alberta, Edmonton, Alberta, Canada, T6G 2G3
| | - William R. Cullen
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver,
British Columbia, Canada, V6T 1Z1
| | - Michael Weinfeld
- Department of Oncology, Cross
Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada, T6G 1Z2
| | - X. Chris Le
- Department
of Laboratory Medicine
and Pathology, 10-102 Clinical Sciences Building, University
of Alberta, Edmonton, Alberta, Canada, T6G 2G3
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17
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Schmidt AC, Mickein K. Qualitative and quantitative characterization of the arsenic-binding behaviour of sulfur-containing peptides and proteins by the coupling of reversed phase liquid chromatography to electrospray ionization mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2012; 47:949-961. [PMID: 22899503 DOI: 10.1002/jms.3025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Phenylarsenic-substituted cysteine-containing peptides and proteins were completely differentiated from their unbound original forms by the coupling of reversed phase liquid chromatography with electrospray ionization mass spectrometry. The analysis of biomolecules possessing structure-stabilizing disulfide bridges after reduction provides new insights into requirements concerning the accessibility of cysteine residues for reducing agents as well as for arsenic compounds in a spatial protein structure. Complementary binding studies performed using direct ESI-MS without chromatographic coupling in different solvent systems demonstrated that more than one binding site were activated for aprotinin and lysozyme in denaturing solvents because of a stronger defolding. From the intensities of the different charge states occurring in the mass spectra as well as from the LC elution behaviour, it can be deduced that the folding state of the arsenic-bound protein species resembles the native, oxidized conformation. In contrast, although the milk protein α-lactalbumin has several disulfide bridges, only one phenylarsenic moiety was bound under strongly denaturing conditions. Because of the charge state distribution in the ESI mass spectra, a conformational change to a molten globule structure is assumed. For the second considered milk protein ß-lactoglobulin, a noncovalent interaction with phenylarsine oxide was detected. In general, smaller apparent binding constants for the condensation reactions of the biomolecules with phenylarsine oxide leading to covalent arsenic-sulfur bindings were determined from direct injection ESI-MS measurements than from LC-ESI-MS coupling. The following order of binding affinities for one phenylarsenic group can be assumed from both ESI-MS and LC-ESI-MS: nonapeptide vasopressin > nonapeptide vasotocin > lysozyme > aprotinin > α-lactalbumin > thioredoxin. Kinetic investigations by LC-ESI-MS yielded a partial reaction order of 2 for vasopressin, Lys and α-lactalbumin and corresponding half-lives of 0.93, 2.56 and 123.5 min, respectively.
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Affiliation(s)
- Anne-Christine Schmidt
- Institute of Analytical Chemistry, Technical University Bergakademie Freiberg, Leipziger Straße 29, D-09599, Freiberg, Germany.
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18
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Watanabe T, Hirano S. Metabolism of arsenic and its toxicological relevance. Arch Toxicol 2012; 87:969-79. [PMID: 22811022 DOI: 10.1007/s00204-012-0904-5] [Citation(s) in RCA: 196] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 07/02/2012] [Indexed: 10/28/2022]
Abstract
Arsenic is a worldwide environmental pollutant and a human carcinogen. It is well recognized that the toxicity of arsenicals largely depends on the oxidoreduction states (trivalent or pentavalent) and methylation levels (monomethyl, dimethyl, and trimethyl) that are present during the process of metabolism in mammals. However, presently, the specifics of the metabolic pathway of inorganic arsenicals have yet to be confirmed. In mammals, there are two possible mechanisms that have been proposed for the metabolic pathway of inorganic arsenicals, oxidative methylation, and glutathione conjugation. Oxidative methylation, which was originally proposed in fungi, is based on findings that arsenite (iAs(III)) is sequentially converted to monomethylarsonic acid (MMA(V)) and dimethylarsinic acid (DMA(V)) in both humans and in laboratory animals such as mice and rats. However, recent in vitro observations have demonstrated that arsenic is only methylated in the presence of glutathione (GSH) or other thiol compounds, which strongly suggests that arsenic is methylated in trivalent forms. The glutathione conjugation mechanism is supported by findings that have shown that most intracellular arsenicals are trivalent and excreted from cells as GSH conjugates. Since non-conjugated trivalent arsenicals are highly reactive with thiol compounds and are easily converted to less toxic corresponding pentavalent arsenicals, the arsenic-glutathione conjugate stability may be the most important factor for determining the toxicity of arsenicals. In addition, "being a non-anionic form" also appears to be a determinant of the toxicity of oxo-arsenicals or thioarsenicals. The present review discusses both the metabolism of arsenic and the toxicity of arsenic metabolites.
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Affiliation(s)
- Takayuki Watanabe
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo, Chiba 260-0856, Japan
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19
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Finnegan PM, Chen W. Arsenic toxicity: the effects on plant metabolism. Front Physiol 2012; 3:182. [PMID: 22685440 PMCID: PMC3368394 DOI: 10.3389/fphys.2012.00182] [Citation(s) in RCA: 363] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2012] [Accepted: 05/17/2012] [Indexed: 12/17/2022] Open
Abstract
The two forms of inorganic arsenic, arsenate (AsV) and arsenite (AsIII), are easily taken up by the cells of the plant root. Once in the cell, AsV can be readily converted to AsIII, the more toxic of the two forms. AsV and AsIII both disrupt plant metabolism, but through distinct mechanisms. AsV is a chemical analog of phosphate that can disrupt at least some phosphate-dependent aspects of metabolism. AsV can be translocated across cellular membranes by phosphate transport proteins, leading to imbalances in phosphate supply. It can compete with phosphate during phosphorylation reactions, leading to the formation of AsV adducts that are often unstable and short-lived. As an example, the formation and rapid autohydrolysis of AsV-ADP sets in place a futile cycle that uncouples photophosphorylation and oxidative phosphorylation, decreasing the ability of cells to produce ATP and carry out normal metabolism. AsIII is a dithiol reactive compound that binds to and potentially inactivates enzymes containing closely spaced cysteine residues or dithiol co-factors. Arsenic exposure generally induces the production of reactive oxygen species that can lead to the production of antioxidant metabolites and numerous enzymes involved in antioxidant defense. Oxidative carbon metabolism, amino acid and protein relationships, and nitrogen and sulfur assimilation pathways are also impacted by As exposure. Readjustment of several metabolic pathways, such as glutathione production, has been shown to lead to increased arsenic tolerance in plants. Species- and cultivar-dependent variation in arsenic sensitivity and the remodeling of metabolite pools that occurs in response to As exposure gives hope that additional metabolic pathways associated with As tolerance will be identified.
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Affiliation(s)
- Patrick M. Finnegan
- Faculty of Natural and Agricultural Sciences, School of Plant Biology and Institute of Agriculture, The University of Western AustraliaCrawley, WA, Australia
| | - Weihua Chen
- Faculty of Natural and Agricultural Sciences, School of Plant Biology and Institute of Agriculture, The University of Western AustraliaCrawley, WA, Australia
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20
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Characterization of the role of protein-cysteine residues in the binding with sodium arsenite. Arch Toxicol 2012; 86:911-22. [PMID: 22422341 DOI: 10.1007/s00204-012-0828-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Accepted: 02/27/2012] [Indexed: 12/15/2022]
Abstract
To better characterize the interaction of protein-cysteines with sodium arsenite, arsenic-binding proteins were identified from the arsenic-resistant Chinese hamster ovary cell line SA7 using a p-aminophenylarsine oxide (PAO)-agarose matrix in combination with proteomic techniques. Twenty of the isolated arsenic-binding proteins were further peptide-mapped by MALDI-Q-TOF-MS. The binding capacity of PAO-agarose-retained proteins was then verified by re-applying Escherichia coli overexpressed recombinant proteins with various numbers of cysteine residues onto the PAO-agarose matrix. The results showed that recombinant heat shock protein 27 (HSP27, with one cysteine residue), reticulocalbin-3 (RCN3, with no cysteine residue), galectin-1 (GAL1, with six cysteine residues), but not peroxiredoxin 6 (Prdx6, with one cysteine residue but not retained by the PAO-agarose matrix), were bound to the PAO-agarose matrix. The six free cysteine residues in GAL1 were individually or double-mutated to alanine by means of site-directed mutagenesis and subjected to CD and ICP-MS analysis. The binding capacity of GAL1 for sodium arsenite was significantly attenuated in C16A, C88A and all double mutant clones. Taken together, our current data suggest that the cysteine residues in GAL1 may play a critical role in the binding of arsenic, but that in the case of RCN3 and Prdx6, this interaction may be mediated by other factors.
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21
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Zhou X, Sun X, Cooper KL, Wang F, Liu KJ, Hudson LG. Arsenite interacts selectively with zinc finger proteins containing C3H1 or C4 motifs. J Biol Chem 2011; 286:22855-63. [PMID: 21550982 DOI: 10.1074/jbc.m111.232926] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Arsenic inhibits DNA repair and enhances the genotoxicity of DNA-damaging agents such as benzo[a]pyrene and ultraviolet radiation. Arsenic interaction with DNA repair proteins containing functional zinc finger motifs is one proposed mechanism to account for these observations. Here, we report that arsenite binds to both CCHC DNA-binding zinc fingers of the DNA repair protein PARP-1 (poly(ADP-ribose) polymerase-1). Furthermore, trivalent arsenite coordinated with all three cysteine residues as demonstrated by MS/MS. MALDI-TOF-MS analysis of peptides harboring site-directed substitutions of cysteine with histidine residues within the PARP-1 zinc finger revealed that arsenite bound to peptides containing three or four cysteine residues, but not to peptides with two cysteines, demonstrating arsenite binding selectivity. This finding was not unique to PARP-1; arsenite did not bind to a peptide representing the CCHH zinc finger of the DNA repair protein aprataxin, but did bind to an aprataxin peptide mutated to a CCHC zinc finger. To investigate the impact of arsenite on PARP-1 zinc finger function, we measured the zinc content and DNA-binding capacity of PARP-1 immunoprecipitated from arsenite-exposed cells. PARP-1 zinc content and DNA binding were decreased by 76 and 80%, respectively, compared with protein isolated from untreated cells. We observed comparable decreases in zinc content for XPA (xeroderma pigmentosum group A) protein (CCCC zinc finger), but not SP-1 (specificity protein-1) or aprataxin (CCHH zinc finger). These findings demonstrate that PARP-1 is a direct molecular target of arsenite and that arsenite interacts selectively with zinc finger motifs containing three or more cysteine residues.
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Affiliation(s)
- Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131-0001, USA
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22
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Bergquist ER, Fischer RJ, Sugden KD, Martin BD. Inhibition by methylated organo-arsenicals of the respiratory 2-oxo-acid dehydrogenases. J Organomet Chem 2009; 694:973-980. [PMID: 20161290 PMCID: PMC2685281 DOI: 10.1016/j.jorganchem.2008.12.028] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Inorganic arsenic that is ingested through drinking water or inhalation is metabolized by biological methylation pathways into organoarsenical metabolites. It is now becoming understood that this metabolism that was formerly considered to be detoxification may contribute as much or more to increasing the toxicity of arsenic. One proposed mode of the toxic action of arsenic and its organoarsenic metabolites is through its binding to proteins and inactivating their enzymatic activity. The classic case has been considered the affinity of the proximal 1,3 sulfhydryl groups of the lipoic acid cofactor of the pyruvate dehydrogenase complex for arsenic. A 2:1 stoichiometry of sulfhydryl to arsenic groups has been measured in proteins and arsenical complexes can be synthesized using free D,L-lipoic acid. The relative importance of this site for arsenic binding has come in to question through the use of methylating bifunctional arsenic complexes that suggested the methylation of an active site histidine may also be important, and the suggestion that arsenic inhibits the pyruvate dehydrogenase complex indirectly by elevating mitochondrial hydrogen peroxide generation. In order to separate the effects of direct trivalent arsenite toxicity from that of hydrogen peroxide and activated oxygen, we studied the inhibition of the PDH complex under conditions that did not generate hydrogen peroxide but did expose the lipoic acid group in its reduced state to arsenicals. We also studied the effects of arsenicals in the inhibition of the α-ketoglutarate dehydrogenase complex. We found that only trivalent arsenical compounds inhibited the activity of both dehydrogenase complexes and only when the lipoic acid was in its reduced form. Arsenite inhibited both enzyme complexes approximately equivalently while monomethylarsenite inhibited the PDH complex to a greater extent than the KGDH complex - although both complexes were very sensitive to inhibition by this complex. Dimethylarsenite inhibition of both complexes was only observed with longer pre-incubation periods. Cumulative inhibition by the reduced arsenical was observed for all complexes indicating a binding mode of inhibition that is dependent upon lipoic acid being in its reduced state.
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Affiliation(s)
- Erik R. Bergquist
- Department of Chemistry, University of Montana, 32 Campus Drive, Missoula, MT 59812, USA
| | - Robert J. Fischer
- Rocky Mountain Laboratories, Laboratory of Zoonotic Pathogens, Hamilton, Montana, USA
| | - Kent D. Sugden
- Department of Chemistry, University of Montana, 32 Campus Drive, Missoula, MT 59812, USA
| | - Brooke D Martin
- Department of Chemistry, University of Montana, 32 Campus Drive, Missoula, MT 59812, USA
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Kitchin KT, Wallace K. Evidence against the nuclear in situ binding of arsenicals–oxidative stress theory of arsenic carcinogenesis. Toxicol Appl Pharmacol 2008; 232:252-7. [DOI: 10.1016/j.taap.2008.06.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Revised: 06/23/2008] [Accepted: 06/26/2008] [Indexed: 12/14/2022]
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24
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Kitchin KT, Wallace K. The role of protein binding of trivalent arsenicals in arsenic carcinogenesis and toxicity. J Inorg Biochem 2008; 102:532-9. [DOI: 10.1016/j.jinorgbio.2007.10.021] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Revised: 10/19/2007] [Accepted: 10/29/2007] [Indexed: 02/01/2023]
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25
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Pia̧tek K, Schwerdtle T, Hartwig A, Bal W. Monomethylarsonous Acid Destroys a Tetrathiolate Zinc Finger Much More Efficiently than Inorganic Arsenite: Mechanistic Considerations and Consequences for DNA Repair Inhibition. Chem Res Toxicol 2008; 21:600-6. [DOI: 10.1021/tx7003135] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Katarzyna Pia̧tek
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland, Institute of Food Technology and Food Chemistry, Technical University Berlin, Gustav-Meyer-Allee 25, D-13355 Berlin, Germany, and Central Institute for Labour Protection—National Research Institute, Czerniakowska 16, 00-701 Warsaw, Poland
| | - Tanja Schwerdtle
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland, Institute of Food Technology and Food Chemistry, Technical University Berlin, Gustav-Meyer-Allee 25, D-13355 Berlin, Germany, and Central Institute for Labour Protection—National Research Institute, Czerniakowska 16, 00-701 Warsaw, Poland
| | - Andrea Hartwig
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland, Institute of Food Technology and Food Chemistry, Technical University Berlin, Gustav-Meyer-Allee 25, D-13355 Berlin, Germany, and Central Institute for Labour Protection—National Research Institute, Czerniakowska 16, 00-701 Warsaw, Poland
| | - Wojciech Bal
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland, Institute of Food Technology and Food Chemistry, Technical University Berlin, Gustav-Meyer-Allee 25, D-13355 Berlin, Germany, and Central Institute for Labour Protection—National Research Institute, Czerniakowska 16, 00-701 Warsaw, Poland
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Kitchin KT, Wallace K. Dissociation of arsenite-peptide complexes: Triphasic nature, rate constants, half-lives, and biological importance. J Biochem Mol Toxicol 2006; 20:48-56. [PMID: 16498640 DOI: 10.1002/jbt.20108] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We determined the number and the dissociation rate constants of different complexes formed from arsenite and two peptides containing either one (RVCAVGNDYASGYHYGV for peptide 20) or three cysteines (LECAWQGK CVEGTEHLYSMKCK for peptide 10) via radioactive 73As-labeled arsenite and vacuum filtration methodology. Nonlinear regression analysis of the dissociation of both arsenite-peptide complexes showed that triphasic fits gave excellent r2 values (0.9859 for peptide 20 and 0.9890 for peptide 10). The first phase of arsenite-peptide dissociation had the largest span (decrease in binding), and the rate was too fast to be measured using vacuum filtration methods. The dissociation rate constants of arsenite-peptide complexes for the second phase were 0.35 and 0.54 min(-1) and for the third phase were 0.0071 and 0.0045 min(-1) for peptides 20 and 10, respectively. For peptide 20, the three spans of triphasic decay were 85%, 9%, and 7% of the total binding of 16.1 nmol/mg protein. For peptide 10, which can bind in both an intermolecular and intramolecular manner, the three spans of triphasic decay were 59%, 16%, and 25% of the total binding of 43.7 nmol/mg protein. Binding of trivalent arsenicals to peptides and proteins can alter their structure and function and contribute to adverse health outcomes such as toxicity and carcinogenicity.
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Affiliation(s)
- Kirk T Kitchin
- Environmental Carcinogenesis Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
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