51
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Yuan F, Yang Z, Tang T, Xie S, Liu F. A 28.6-kD small heat shock protein (MnHSP28.6) protects Macrobrachium nipponense against heavy metal toxicity and oxidative stress by virtue of its anti-aggregation activity. FISH & SHELLFISH IMMUNOLOGY 2019; 95:635-643. [PMID: 31678183 DOI: 10.1016/j.fsi.2019.10.053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 10/22/2019] [Accepted: 10/27/2019] [Indexed: 06/10/2023]
Abstract
Small heat shock proteins (sHSPs) are ATP-independent chaperones and involved into various physiological and stress processes. In the present study, a 28.6-kD sHSP coding gene, MnHSP28.6, was cloned and characterized from the oriental river prawn Macrobrachium nipponense. Tissue distribution analysis via qPCR and western blot revealed that MnHSP28.6 predominantly expressed in muscle. The temporal transcription of MnHSP28.6 in muscle after bacterial challenge, heavy metal exposure and doxorubicin (DOX) injection was investigated by qPCR. The results showed that the expression of MnHSP28.6 were strongly enhanced by both Cd2+ and Cu2+ exposure, as well as DOX injection, but not by bacterial infection. Aggregation assays showed that recombinant MnHSP28.6 could effectively prevent temperature-induced aggregation of citrate synthase, and reduction-induced aggregation of insulin in vitro. MnHSP28.6 also could protect muscle extracts from heat-induced protein denaturation and superoxide dismutase (SOD) inactivation. Expressing MnHSP28.6 in E. coli conferred host cell impressive protection against H2O2 compared to control. These results suggest a protective role of MnHSP28.6 in maintaining protein homeostasis, preventing aggregation, promoting resistance to heavy metal and keeping redox balance.
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Affiliation(s)
- Fengyu Yuan
- The Key Laboratory of Zoological Systematics and Application, College of Life Sciences, Hebei University, Baoding, Hebei, 071002, China
| | - Zilan Yang
- The Key Laboratory of Zoological Systematics and Application, College of Life Sciences, Hebei University, Baoding, Hebei, 071002, China
| | - Ting Tang
- The Key Laboratory of Zoological Systematics and Application, College of Life Sciences, Hebei University, Baoding, Hebei, 071002, China
| | - Song Xie
- The Key Laboratory of Zoological Systematics and Application, College of Life Sciences, Hebei University, Baoding, Hebei, 071002, China.
| | - Fengsong Liu
- The Key Laboratory of Zoological Systematics and Application, College of Life Sciences, Hebei University, Baoding, Hebei, 071002, China.
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52
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Zhang T, Li Y, Chen C, Liu X, Tian Y, Zeng S, He M. Rapid screening and quantification of multi-class antibiotic pollutants in water using a planar waveguide immunosensor. RSC Adv 2019; 9:38422-38429. [PMID: 35540241 PMCID: PMC9075870 DOI: 10.1039/c9ra06796e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/15/2019] [Indexed: 11/21/2022] Open
Abstract
Antibiotics are commonly used in livestock-related agriculture and aquaculture, but they also remain in water and potentially threaten human health. Immunosensors are attractive tools for the rapid detection of antibiotics in water due to their high sensitivity and low costs. However, the simultaneous detection of multi-class antibiotics remains a challenge due to the limited number of detection sites on the immunochip. Also, matrix effects hinder the practical application of these sensors. This paper presents a method for multi-class antibiotic detection in real water using a planar waveguide immunosensor (PWI). We integrate the screening and quantitive detection sites on the same immunochip, and a single screening detection site could detect multi-class antibiotics from the same family, increasing the detection types of analytes. In addition, to eliminate the matrix effects, we develop a testing buffer for real water detection, so that complex pretreatments of the samples can be omitted. Using our sensor and testing buffer, we detect 14 different antibiotics in real water. Lincomycin can be detected with a detection limit of 0.01 μg L−1, and 13 quinolones can be screened in a single assay. These results demonstrate that this planar waveguide immunosensor is capable of simultaneous screening and quantification of multi-class antibiotic pollutants and is expected to be applied for practical environmental monitoring. We present a method for simultaneous screening and quantitative detection of multi-class antibiotics in real water using planar waveguide immunosensors.![]()
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Affiliation(s)
- Tianmu Zhang
- Center for Sensor Technology of Environment and Health, Tsinghua University Beijing 100084 China .,State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University Beijing 100084 China
| | - Yijun Li
- Center for Sensor Technology of Environment and Health, Tsinghua University Beijing 100084 China .,State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University Beijing 100084 China
| | - Chunfei Chen
- Guangxi Environmental Monitoring Centre Nanning 530028 China
| | - Xiaoping Liu
- Guangxi Environmental Monitoring Centre Nanning 530028 China
| | - Yan Tian
- Guangxi Environmental Monitoring Centre Nanning 530028 China
| | - Siyu Zeng
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University Beijing 100084 China
| | - Miao He
- Center for Sensor Technology of Environment and Health, Tsinghua University Beijing 100084 China .,State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University Beijing 100084 China
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53
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Raghushaker CR, Chandra S, Chakrabarty S, Kabekkodu SP, Satyamoorthy K, Mahato KK. Detection of mitochondrial dysfunction in vitro by laser-induced autofluorescence. JOURNAL OF BIOPHOTONICS 2019; 12:e201900056. [PMID: 31251452 DOI: 10.1002/jbio.201900056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 06/26/2019] [Accepted: 06/27/2019] [Indexed: 06/09/2023]
Abstract
Mitochondrion plays a significant role in a variety of biological functions. Because of their diverse character and location in the cellular systems, mitochondria commonly get exposed to various extrinsic and intrinsic cellular stresses. The present study reports a novel approach to detection of mitochondrial dysfunction based on tryptophan autofluorescence of its proteins in mouse liver, using laser-induced fluorescence (LIF) as a tool. Mitochondria, isolated from the mouse liver, were initially tested for purity and integrity using lactate dehydrogenase and succinate dehydrogenase (SDH) assays. Mitochondrial stress was induced by treating the isolated mitochondria with heavy metals at 10 and 0.01 mM for sodium arsenite and mercuric chloride, respectively. Upon treatment with the heavy metal, tryptophan autofluorescence quenching was recorded at 281 nm excitation. The functional integrity of the mitochondria treated with heavy metals was evaluated by measuring SDH and cytochrome c oxidase activities at various concentrations of mitochondria, which showed impaired activity as compared to control upto a concentration of 6.25 μg. A significant shift was also observed in the autofluorescence of proteins upto the level below 1 μg, suggesting their conformational change and hence altered structural integrity of mitochondria. Circular dichroism spectroscopy data of the mitochondrial proteins treated with heavy metals further validates their conformational change as compared to untreated control. The present study clearly shows that the LIF can be a novel detection tool to detect altered structural integrity of cellular mitochondria upon stress, and it also possesses the potentiality to combine with other interdisciplinary modalities.
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Affiliation(s)
- Chandavalli R Raghushaker
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Subhash Chandra
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Sanjiban Chakrabarty
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Shama P Kabekkodu
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Kapaettu Satyamoorthy
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Krishna K Mahato
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
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54
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Kolbert Z, Molnï R Ï, Olï H D, Feigl G, Horvï Th E, Erdei L, Ï Rdï G A, Rudolf E, Barth T, Lindermayr C. S-Nitrosothiol Signaling Is involved in Regulating Hydrogen Peroxide Metabolism of Zinc-Stressed Arabidopsis. PLANT & CELL PHYSIOLOGY 2019; 60:2449-2463. [PMID: 31340034 DOI: 10.1093/pcp/pcz138] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 07/05/2019] [Indexed: 05/08/2023]
Abstract
Accumulation of heavy metals such as zinc (Zn) disturbs the metabolism of reactive oxygen (e.g. hydrogen peroxide, H2O2) and nitrogen species (e.g. nitric oxide, NO; S-nitrosoglutathione, GSNO) in plant cells; however, their signal interactions are not well understood. Therefore, this study examines the interplay between H2O2 metabolism and GSNO signaling in Arabidopsis. Comparing the Zn tolerance of the wild type (WT), GSNO reductase (GSNOR) overexpressor 35S::FLAG-GSNOR1 and GSNOR-deficient gsnor1-3, we observed relative Zn tolerance of gsnor1-3, which was not accompanied by altered Zn accumulation capacity. Moreover, in gsnor1-3 plants Zn did not induce NO/S-nitrosothiol (SNO) signaling, possibly due to the enhanced activity of NADPH-dependent thioredoxin reductase. In WT and 35S::FLAG-GSNOR1, GSNOR was inactivated by Zn, and Zn-induced H2O2 is directly involved in the GSNOR activity loss. In WT seedlings, Zn resulted in a slight intensification of protein nitration detected by Western blot and protein S-nitrosation observed by resin-assisted capture of SNO proteins (RSNO-RAC). LC-MS/MS analyses indicate that Zn induces the S-nitrosation of ascorbate peroxidase 1. Our data collectively show that Zn-induced H2O2 may influence its own level, which involves GSNOR inactivation-triggered SNO signaling. These data provide new evidence for the interplay between H2O2 and SNO signaling in Arabidopsis plants affected by metal stress.
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Affiliation(s)
- Zs Kolbert
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - Ï Molnï R
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - D Olï H
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - G Feigl
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - E Horvï Th
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - L Erdei
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - A Ï Rdï G
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - E Rudolf
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum M�nchen-German Research Center for Environmental Health, M�nchen/Neuherberg, Germany
| | - T Barth
- Research Unit Protein Science, Helmholtz Zentrum M�nchen-German Research Center for Environmental Health, M�nchen/Neuherberg, Germany
| | - C Lindermayr
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum M�nchen-German Research Center for Environmental Health, M�nchen/Neuherberg, Germany
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55
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Flores-Montoya MG, Bill CA, Vines CM, Sobin C. Early chronic low-level lead exposure reduced C-C chemokine receptor 7 in hippocampal microglia. Toxicol Lett 2019; 314:106-116. [PMID: 31306743 PMCID: PMC7815484 DOI: 10.1016/j.toxlet.2019.07.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 06/11/2019] [Accepted: 07/06/2019] [Indexed: 01/10/2023]
Abstract
Chronic low-level lead exposure alters cognitive function in young children however the mechanisms mediating these deficits in the brain are not known. Previous studies in our laboratory showed that early lead exposure reduced the number of microglial cells in hippocampus/dentate gyrus of C57BL/6 J mice. In the current study, C-C chemokine receptor 7 (CCR7) and major histocompatibility complex II (MHC II) were examined to investigate whether these neuroimmune factors which are known to trigger cell migration and antigen presentation, were altered by early chronic lead exposure. Thirty-six C57BL/6 J male mice were exposed to 0 ppm (controls, n = 12), 30 ppm (low-dose, n = 12), or 430 ppm (higher-dose, n = 12) of lead acetate via dams' milk from postnatal day (PND) 0 to 28. Flow cytometry was used to quantify cell types and cell surface expression of MHC II and CCR7 in hippocampal and whole brain microglia. Non-parametric independent samples median tests were used to test for statistically significant differences between groups. As compared to controls, CCR7 in hippocampal microglia was decreased in the low-dose group, measured as geometric mean fluorescence intensity (GMFI); in the higher-dose group CCR7+MHC II- hippocampal microglia were decreased. Further analyses revealed that the higher-dose group had decreased percentage of CCR7+MHC II- hippocampal macrophages as compared to controls but increased MHC II levels in CCR7+MHC II+ hippocampal macrophages as compared to controls. It was also noted that lead exposure disrupted the balance of MHC II and/or CCR7 in lead exposed animals. Reduced CCR7 in hippocampal microglia might alter the neuroimmune environment in hippocampi of lead exposed animals. Additional studies are needed to test this possibility.
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Affiliation(s)
- Mayra Gisel Flores-Montoya
- Dept of Psychology, The University of Texas at El Paso, El Paso, TX, USA; Dept of Psychology, Carleton College, Northfield, MN, USA.
| | - Colin A Bill
- Dept of Biological Sciences, The University of Texas at El Paso, El Paso, TX, USA
| | - Charlotte M Vines
- Dept of Biological Sciences, The University of Texas at El Paso, El Paso, TX, USA
| | - Christina Sobin
- Dept of Public Health Sciences, The University of Texas at El Paso, El Paso, TX, USA; Laboratory of Neuroendocrinology, The Rockefeller University, New York, NY, USA
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56
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Easy fabrication of mussel inspired coated foam and its optimization for the facile removal of copper from aqueous solutions. J Colloid Interface Sci 2019; 552:401-411. [DOI: 10.1016/j.jcis.2019.05.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/17/2019] [Accepted: 05/19/2019] [Indexed: 02/07/2023]
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57
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Zaksas NP. Solid Sampling in Analysis of Various Plants Using Two-Jet Plasma Atomic Emission Spectrometry. APPLIED SPECTROSCOPY 2019; 73:870-878. [PMID: 30947521 DOI: 10.1177/0003702819845935] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The possibility of two-jet plasma atomic emission spectrometry for analysis of different plants using solid sample preparation and unified calibration samples was investigated. The certified reference materials of wheat, maize, rice, potato, grass mix, birch leaves, and Elodea canadensis were used for analysis. On the basis of the behavior of these plants in the plasma, they were divided into two groups: starch-containing materials (cereal and root crops) and leaves/grass. It was found that the previous sample carbonization should be used for analysis of starch-containing plants while leaves and grass could be analyzed by the direct technique. Carbonization was only applied for determining low concentrations of trace elements in leaves and grass. The calibration samples based on graphite powder and simple sample preparation, dilution of powdered sample with a spectroscopic buffer, were used for both direct analysis and analysis after carbonization. Such an approach allowed estimation of B, Ba, Be, Cd, Co, Cr, Cu, Ga, Fe, Mn, Ni, Pb, Si, Sr, V, and Zn in different plants. The limits of detection (LODs) provided by the direct technique were at the level of (µg·g-1): n × 0.1 for Cd, Cu, and Mn; n for B, Ba, Co, Cr, Fe, Ga, Ni, Pb, Sr, V, and Zn; n × 10 for Si. Carbonization allowed improving LODs of elements several times depending on the thermal stability and mineral composition of plants. The LODs of elements in plants obtained after carbonization are the following (µg·g-1): n × 0.01 for Be, Cd, Cu, and Mn; n × 0.1 for Co, Cr, Fe, Ga, Ni, Pb, Sr, V, Zn; and n for Si. The techniques suggested are fast, easily workable, and do not require harmful chemical reagents. In some cases, the influence of variable matrices and different element species on analytical signal of elements was not completely suppressed; the deviation of element concentrations from the true values was discussed.
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Affiliation(s)
- Natalia P Zaksas
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
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58
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Matilda C, Mannully S, Viditha R, Shanthi C. Protein profiling of metal‐resistantBacillus cereusVITSH1. J Appl Microbiol 2019; 127:121-133. [DOI: 10.1111/jam.14293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 04/09/2019] [Accepted: 04/23/2019] [Indexed: 02/04/2023]
Affiliation(s)
- C.S. Matilda
- School of Bio Sciences and Technology Vellore Institute of Technology Vellore India
| | - S.T. Mannully
- School of Bio Sciences and Technology Vellore Institute of Technology Vellore India
| | - R.P. Viditha
- School of Bio Sciences and Technology Vellore Institute of Technology Vellore India
| | - C. Shanthi
- School of Bio Sciences and Technology Vellore Institute of Technology Vellore India
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59
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Louati I, Hadrich B, Nasri M, Belbahri L, Woodward S, Mechichi T. Modelling of Reactive Black 5 decolourization in the presence of heavy metals by the newly isolated
Pseudomonas aeruginosa
strain Gb30. J Appl Microbiol 2019; 126:1761-1771. [DOI: 10.1111/jam.14262] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 02/11/2019] [Accepted: 03/18/2019] [Indexed: 11/28/2022]
Affiliation(s)
- I. Louati
- Laboratory of Enzyme Engineering and Microbiology National School of Engineers of Sfax University of Sfax Sfax Tunisia
| | - B. Hadrich
- Unité de Biotechnologie des Algues Biological Engineering Department National School of Engineers of Sfax University of Sfax Sfax Tunisia
| | - M. Nasri
- Laboratory of Enzyme Engineering and Microbiology National School of Engineers of Sfax University of Sfax Sfax Tunisia
| | - L. Belbahri
- Laboratoire de biologie des sols Université de Neuchâtel Neuchâtel Switzerland
| | - S. Woodward
- School of Biological Sciences University of Aberdeen Aberdeen UK
| | - T. Mechichi
- Laboratory of Enzyme Engineering and Microbiology National School of Engineers of Sfax University of Sfax Sfax Tunisia
- Laboratory of Biochemistry and Enzymatic Engineering of Lipases National School of Engineers of Sfax University of Sfax Sfax Tunisia
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60
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Ford AE, Denicourt C, Morano KA. Thiol stress-dependent aggregation of the glycolytic enzyme triose phosphate isomerase in yeast and human cells. Mol Biol Cell 2019; 30:554-565. [PMID: 30601716 PMCID: PMC6589699 DOI: 10.1091/mbc.e18-10-0616] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
The eukaryotic cytosolic proteome is vulnerable to changes in proteostatic and redox balance caused by temperature, pH, oxidants, and xenobiotics. Cysteine-containing proteins are especially at risk, as the thiol side chain is subject to oxidation, adduction, and chelation by thiol-reactive compounds. The thiol-chelating heavy metal cadmium is a highly toxic environmental pollutant demonstrated to induce the heat shock response and recruit protein chaperones to sites of presumed protein aggregation in the budding yeast Saccharomyces cerevisiae. However, endogenous targets of cadmium toxicity responsible for these outcomes are largely unknown. Using fluorescent protein fusion to cytosolic proteins with known redox-active cysteines, we identified the yeast glycolytic enzyme triose phosphate isomerase as being aggregation-prone in response to cadmium and to glucose depletion in chronologically aging cultures. Cadmium-induced aggregation was limited to newly synthesized Tpi1 that was recruited to foci containing the disaggregase Hsp104 and the peroxiredoxin chaperone Tsa1. Misfolding of nascent Tpi1 in response to both cadmium and glucose-depletion stress required both cysteines, implying that thiol status in this protein directly influences folding. We also demonstrate that cadmium proteotoxicity is conserved between yeast and human cells, as HEK293 and HCT116 cell lines exhibit recruitment of the protein chaperone Hsp70 to visible foci. Moreover, human TPI, mutations in which cause a glycolytic deficiency syndrome, also forms aggregates in response to cadmium treatment, suggesting that this conserved enzyme is folding-labile and may be a useful endogenous model for investigating thiol-specific proteotoxicity.
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Affiliation(s)
- Amy E Ford
- Department of Microbiology and Molecular Genetics, University of Texas McGovern Medical School at Houston, Houston, TX 77030.,MD Anderson UT Health Graduate School of Biomedical Sciences, Houston, TX 77030
| | - Catherine Denicourt
- Department of Integrative Biology and Pharmacology, University of Texas McGovern Medical School at Houston, Houston, TX 77030
| | - Kevin A Morano
- Department of Microbiology and Molecular Genetics, University of Texas McGovern Medical School at Houston, Houston, TX 77030
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61
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Oxidative stress in the neurodegenerative brain following lifetime exposure to lead in rats: Changes in lifespan profiles. Toxicology 2019; 411:101-109. [DOI: 10.1016/j.tox.2018.11.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 10/26/2018] [Accepted: 11/12/2018] [Indexed: 12/27/2022]
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62
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Kumar Babele P. Zinc oxide nanoparticles impose metabolic toxicity by de-regulating proteome and metabolome in Saccharomyces cerevisiae. Toxicol Rep 2018; 6:64-73. [PMID: 30581761 PMCID: PMC6297892 DOI: 10.1016/j.toxrep.2018.12.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 11/28/2018] [Accepted: 12/05/2018] [Indexed: 12/31/2022] Open
Abstract
Untargeted proteomic and metabolic approaches provide complete toxicity assessment. ZnO-NPs de-regulate the proteome and metabolome of S. cerevisiae. ZnO-NPs affect the key metabolites of central metabolic pathways. Protein and/or metabolite can be used as biomarker specific to the ZnO-NPs induced toxicity.
As zinc oxide nanoparticles are being increasingly used in various applications, it is important to assess their potential toxic implications. Stress responses and adaptations are primarily controlled by modulation in cellular proteins (enzyme) and concentration of metabolites. To date proteomics or metabolomics applications in nanotoxicity assessment have been applied to a restricted extent. Here we utilized 2DE and 1H NMR based proteomics and metabolomics respectively to delineate the toxicity mechanism of zinc oxide nanoparticles (ZnO-NPs) in budding yeast S. cerevisiae. We found that the physiological and metabolic processes were altered in the S. cerevisiae upon ZnO-NPs exposure. Almost 40% proteins were down-regulated in ZnO-NPs (10 mg L−1) exposed cell as compared to control. Metabolomics and system biology based pathway analysis, revealed that ZnO-NPs repressed a wide range of key metabolites involved in central carbon metabolism, cofactors synthesis, amino acid and fatty acid biosynthesis, purines and pyrimidines, nucleoside and nucleotide biosynthetic pathways. These metabolic changes may be associated with the energy metabolism, antioxidation, DNA and protein damage and membrane stability. We concluded that untargeted proteomic and metabolic approaches provide more complete measurements and suggest probable molecular mechanisms of nanomaterials toxicity.
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Affiliation(s)
- Piyoosh Kumar Babele
- Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal, 462066, Madhya Pradesh, India
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63
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Zhao M, Zacharia NS. Protein encapsulation via polyelectrolyte complex coacervation: Protection against protein denaturation. J Chem Phys 2018; 149:163326. [DOI: 10.1063/1.5040346] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Mengmeng Zhao
- Department of Polymer Engineering, University of Akron, Akron, Ohio 44325, USA
| | - Nicole S. Zacharia
- Department of Polymer Engineering, University of Akron, Akron, Ohio 44325, USA
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64
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Abstract
Cadmium is a nonessential heavy metal and an industrial and environmental pollutant. It has been known that cadmium must enter cells to cause damage. To understand the transport systems responsible for cadmium entry into cells, it is important to determine the precise mechanisms underlying cadmium toxicity. Numerous studies have sought to unravel the exact pathways by which cadmium enters various cells and the mechanisms by which it causes toxicity in the organs of human and animals. The purpose of this review is to present the progress made regarding the mechanisms of cadmium transport in various cells and the mechanisms underlying cadmium toxicity in organs.
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Affiliation(s)
- Ken-Ichi Ohba
- Kitasato University School of Allied Health Sciences
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65
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Hardneck F, Israel G, Pool E, Maree L. Quantitative assessment of heavy metal effects on sperm function using computer-aided sperm analysis and cytotoxicity assays. Andrologia 2018; 50:e13141. [PMID: 30225848 DOI: 10.1111/and.13141] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 07/31/2018] [Accepted: 08/03/2018] [Indexed: 02/04/2023] Open
Abstract
One known environmental risk factor impacting on human reproduction is heavy metal pollution. Although some metals (e.g., Cu, Se and Zn) have protective effects on the male reproductive system in low doses, heavy metals can accumulate to toxic levels and result in poor semen quality and decreased sperm function. We investigated the effect of CuSO4 and CdCl2 (10, 50, 100 and 250 µg/ml or 500 µg/ml) on human sperm motility and vitality by using computer-aided sperm analysis (CASA) and two cytotoxicity assays (WST-1 and XTT). Several sperm motility parameters were significantly reduced after 5 hr of exposure to the highest concentrations of CuSO4 (250 µg/ml) and CdCl2 (500 µg/ml). The WST-1 assay also revealed significantly lower absorbance values for 50, 100 and 250 µg/ml CuSO4 and for 500 µg/ml CdCl2 ; however, no significant effect was seen with XTT. The calculated average IC50 value was 50.31± 4.34 µg/ml for CuSO4 and 392.32 ±76.79 µg/ml for CdCl2 . The effects of these metals were confirmed with MgCl2 , a positive control. This study provides threshold concentrations for the harmful effect of CuSO4 and CdCl2 on human spermatozoa and recommends the use of WST-1 as vitality assay in future in vitro studies.
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Affiliation(s)
- Farren Hardneck
- Department of Medical Bioscience, University of the Western Cape, Bellville, South Africa
| | - Gadieja Israel
- Department of Medical Bioscience, University of the Western Cape, Bellville, South Africa
| | - Edmund Pool
- Department of Medical Bioscience, University of the Western Cape, Bellville, South Africa
| | - Liana Maree
- Department of Medical Bioscience, University of the Western Cape, Bellville, South Africa
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66
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Yu T, Laird JR, Prescher JA, Thorpe C. Gaussia princeps luciferase: a bioluminescent substrate for oxidative protein folding. Protein Sci 2018; 27:1509-1517. [PMID: 29696739 DOI: 10.1002/pro.3433] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/20/2018] [Accepted: 04/23/2018] [Indexed: 11/07/2022]
Abstract
Gaussia princeps luciferase (GLuc) generates an intense burst of blue light when exposed to coelenterazine in the absence of ATP. Here we show that this 5-disulfide containing enzyme can be used as a facile and convenient substrate for studies of oxidative protein folding. Reduced GLuc (rGLuc), with 10 free cysteine residues, is completely inactive as a luciferase but >60% bioluminescence activity, compared to controls, can be recovered using a range of oxidizing regimens in the absence of the exogenous shuffling activity of protein disulfide isomerase (PDI). The sulfhydryl oxidase QSOX1 can be assayed using rGLuc in a simple bioluminescence plate reader format. Similarly, low concentrations of rGLuc can be oxidized by millimolar levels of dehydroascorbate, hydrogen peroxide or much lower concentrations of sodium tetrathionate. The oxidative refolding of rGLuc in the presence of a range of glutathione redox buffers is only marginally accelerated by micromolar levels of PDI. This modest rate enhancement probably results from a relatively simple disulfide connectivity in native GLuc; reflecting two homologous domains each carrying two disulfide bonds with a single interdomain disulfide. When GLuc is reoxidized under denaturing conditions the resulting scrambled protein (sGLuc) can be used in a sensitive bioluminescence assay for reduced PDI in the absence of added exogenous thiols. Finally, the general facility by which rGLuc can recover bioluminescent activity in vitro provides a sensitive method for the assessment of inhibitors of oxidative protein folding.
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Affiliation(s)
- Tiantian Yu
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, 19716
| | - Joanna R Laird
- Department of Chemistry, University of California at Irvine, Irvine, California, 92697
| | - Jennifer A Prescher
- Department of Chemistry, University of California at Irvine, Irvine, California, 92697
| | - Colin Thorpe
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, 19716
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67
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Rahman A, Khan KM, Rao MS. Exposure to low level of lead during preweaning period increases metallothionein-3 expression and dysregulates divalent cation levels in the brain of young rats. Neurotoxicology 2018; 65:135-143. [PMID: 29452138 DOI: 10.1016/j.neuro.2018.02.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 02/11/2018] [Accepted: 02/12/2018] [Indexed: 12/11/2022]
Abstract
Lead (Pb) is a neurotoxic heavy metal, but the mechanism of its neurotoxicity is not clearly understood. Expression of metallothioneins (MTs) is induced in response to heavy metal exposure as a protective mechanism against heavy metal toxicity. There are several isoforms of MTs (MT-1 to 4), of which MT-3 is the neuron specific isoform, which also has neurite growth inhibitory effects. Whereas, the induction of MT-1 and 2 in response to Pb has been reported, the effect of Pb on the expression of MT-3 in the brain has not been documented. This study aimed at investigating the effect of Pb exposure on the expression of MT-3 in the cerebrum and hippocampus. Wistar rat pups were exposed to Pb via their dams' drinking water (0.2% lead acetate in deionized water) from postnatal day (PND) 0 to 21 and directly via drinking water until PND30. Expression of MT-3 was measured by Western blot and quantitative RT-PCR. MT-3 localization was done by immunohistochemistry. Divalent metal ions were analysed by atomic absorption spectrophotometry. Levels of Pb in blood and cerebrum were significantly increased, while that of copper (Cu), zinc (Zn) and manganese (Mn) were significantly decreased in the Pb-exposed rats at both PND21 and PND30. MT-3 protein was significantly increased in the cerebrum (by 2.5-fold) and in hippocampus (1.4 to 3.2-fold) in both PND21 and PND30 Pb-exposed rats over controls. MT-3 gene expression also increased in the cerebrum (by 42%), and in the hippocampus (by 65% and 43% in the PND21 and PND30 rats, respectively), in the Pb-exposed rats over controls, but the increase was statistically significant (p < 0.05) only in the PND30 rats. Pb exposure significantly increased (p < 0.05) percentage of MT-3 immunoreactive cells in Cornu Ammonis and dentate gyrus regions in the PND21 rats, and in the Cornu Ammonis 1, dentate gyrus and cortex regions in the PND30 rats. Our data thus provide convincing evidence that exposure to low levels of Pb during preweaning period increases the expression of MT-3 in the brain of rats.
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Affiliation(s)
- Abdur Rahman
- Department of Food Science and Nutrition, College of Life Sciences, Kuwait University, Kuwait.
| | - Khalid M Khan
- Department of Anatomy, Faculty of Medicine, Kuwait University, Kuwait
| | - Muddanna S Rao
- Department of Anatomy, Faculty of Medicine, Kuwait University, Kuwait
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68
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Kelley AR, Colley ME, Perry G, Bach SBH. Incubation with Cu(II) and Zn(II) salts enhances MALDI-TOF mass spectra of amyloid-beta and α-synuclein toward in vivo analysis. JOURNAL OF MASS SPECTROMETRY : JMS 2018; 53:162-171. [PMID: 29111606 DOI: 10.1002/jms.4044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 10/18/2017] [Accepted: 10/23/2017] [Indexed: 06/07/2023]
Abstract
Insoluble senile plaque aggregates are indicative of Alzheimer's disease pathology. A similar phenomenon occurs in Parkinson's disease with the build-up of Lewy bodies. The analysis of senile plaques, and other brain samples, from Alzheimer's disease and Parkinson's disease patients by matrix-assisted laser desorption/ionization mass spectrometry has advantages but also presents obstacles because of the nature of the processes utilized in isolation procedures and storage. Salts, buffers, and detergents necessary in the isolation of biological species may cause adducts and ion suppression that convolute the spectra obtained. We previously determined that amyloid-beta from isolated senile plaque deposits fragment similarly to the synthetic 40 and 42 amino acid peptide when analyzed by matrix-assisted laser desorption/ionization mass spectrometry. In addition, α-synuclein also fragments predictably by in-source decay. This provides information that may be applied to the identification and localization of amyloid-beta and α-synuclein in senile plaques and intact tissue sections. Ion suppression must still be accounted for when analyzing biological samples, which makes identifying fragments at lower abundance difficult. The addition of certain transition-metal salts (Cu(II), Zn(II)) to the sample prior to analysis serves to "clean" the spectra and allow the peptide fragments produced to be observed with a much higher signal to noise and occasionally, improved resolution. We present a systematic study of incubation with different metal salts and their impact on the quality of the spectra, as well as the role of the binding of the metals to the model biological compounds, obtained for synthetic amyloid-beta, synthetic α-synuclein, and isolated senile plaques. The optimized sample preparation methods presented will provide for simpler and more thorough identification of these biologically relevant species in human-derived samples.
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Affiliation(s)
- Andrea R Kelley
- Department of Chemistry, University of Texas at San Antonio, One UTSA Blvd., San Antonio, TX, USA
| | - Madeline E Colley
- Department of Chemistry, University of Texas at San Antonio, One UTSA Blvd., San Antonio, TX, USA
| | - George Perry
- Department of Chemistry, University of Texas at San Antonio, One UTSA Blvd., San Antonio, TX, USA
| | - Stephan B H Bach
- Department of Chemistry, University of Texas at San Antonio, One UTSA Blvd., San Antonio, TX, USA
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69
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LaVoie SP, Summers AO. Transcriptional responses of Escherichia coli during recovery from inorganic or organic mercury exposure. BMC Genomics 2018; 19:52. [PMID: 29338696 PMCID: PMC5769350 DOI: 10.1186/s12864-017-4413-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/22/2017] [Indexed: 12/22/2022] Open
Abstract
Background The protean chemical properties of mercury have long made it attractive for diverse applications, but its toxicity requires great care in its use, disposal, and recycling. Mercury occurs in multiple chemical forms, and the molecular basis for the distinct toxicity of its various forms is only partly understood. Global transcriptomics applied over time can reveal how a cell recognizes a toxicant and what cellular subsystems it marshals to repair and recover from the damage. The longitudinal effects on the transcriptome of exponential phase E. coli were compared during sub-acute exposure to mercuric chloride (HgCl2) or to phenylmercuric acetate (PMA) using RNA-Seq. Results Differential gene expression revealed common and distinct responses to the mercurials throughout recovery. Cultures exhibited growth stasis immediately after each mercurial exposure but returned to normal growth more quickly after PMA exposure than after HgCl2 exposure. Correspondingly, PMA rapidly elicited up-regulation of a large number of genes which continued for 30 min, whereas fewer genes were up-regulated early after HgCl2 exposure only some of which overlapped with PMA up-regulated genes. By 60 min gene expression in PMA-exposed cells was almost indistinguishable from unexposed cells, but HgCl2 exposed cells still had many differentially expressed genes. Relative expression of energy production and most metabolite uptake pathways declined with both compounds, but nearly all stress response systems were up-regulated by one or the other mercurial during recovery. Conclusions Sub-acute exposure influenced expression of ~45% of all genes with many distinct responses for each compound, reflecting differential biochemical damage by each mercurial and the corresponding resources available for repair. This study is the first global, high-resolution view of the transcriptional responses to any common toxicant in a prokaryotic model system from exposure to recovery of active growth. The responses provoked by these two mercurials in this model bacterium also provide insights about how higher organisms may respond to these ubiquitous metal toxicants. Electronic supplementary material The online version of this article (10.1186/s12864-017-4413-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Stephen P LaVoie
- Department of Microbiology, University of Georgia, Athens, GA, 30602, USA.
| | - Anne O Summers
- Department of Microbiology, University of Georgia, Athens, GA, 30602, USA.
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Khan S, Khan NA, Bano B. In-sights into the effect of heavy metal stress on the endogenous mustard cystatin. Int J Biol Macromol 2017; 105:1138-1147. [PMID: 28754626 DOI: 10.1016/j.ijbiomac.2017.07.146] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Revised: 06/04/2017] [Accepted: 07/24/2017] [Indexed: 01/07/2023]
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71
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Anjos VA, Sandrini JZ, Martinez CBR, Souza MM. Characterization of MXR activity in the sea anemone Bunodosoma cangicum exposed to copper. Comp Biochem Physiol C Toxicol Pharmacol 2017; 202:12-18. [PMID: 28754376 DOI: 10.1016/j.cbpc.2017.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/17/2017] [Accepted: 07/20/2017] [Indexed: 01/28/2023]
Abstract
Transmembrane proteins of the ABC family contribute to a multiple xenobiotic resistance (MXR) phenotype in cells, driving the extrusion of toxic substances. This phenotype promotes a high degree of protection against xenobiotics. The present study provides a better understanding of the MXR activity in the podal disk cells of Bunodosoma cangicum exposed to copper, and further establishes the relationship between protein activity (measured by accumulation of rhodamine-B) and bioaccumulation of copper in these cells. Sea anemone cells were exposed for 24h to copper (0, 7.8 and 15.6μg/L) in presence and absence of MXR blocker (verapamil 50μM). Results indicate that copper exposure increases intracellular metal content when ABC proteins were blocked, causing an increase in cellular death. The present study also verified the relationship between MXR activity, ATP depletion, and general metabolic activity (by MTT). MXR activity decreased in treatment groups exposed to copper concentrations of 15.6μg/L and 10mM energy depleting potassium cyanide. Metabolic activity increased in cells exposed to 7.8μgCu/L, but 15.6μgCu/L was similar to 0 and 7.8μg/L. The presence of copper decreased the ABC proteins expression. The present study improves the knowledge of MXR in anemone cells and shows that this activity is closely associated with copper extrusion. Also, the copper exposure is able to modify the metabolic state and to lead to cytotoxicity when cells cannot defend themselves.
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Affiliation(s)
- Vanessa Abelaira Anjos
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, Rio Grande do Sul, Brazil
| | - Juliana Zomer Sandrini
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, Rio Grande do Sul, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, Rio Grande, do Sul, Brazil
| | | | - Marta Marques Souza
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, Rio Grande do Sul, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, Rio Grande, do Sul, Brazil.
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72
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Tamás MJ, Fauvet B, Christen P, Goloubinoff P. Misfolding and aggregation of nascent proteins: a novel mode of toxic cadmium action in vivo. Curr Genet 2017; 64:177-181. [PMID: 28936749 PMCID: PMC5778182 DOI: 10.1007/s00294-017-0748-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 09/08/2017] [Accepted: 09/11/2017] [Indexed: 01/29/2023]
Abstract
Cadmium is a highly poisonous metal and a human carcinogen, but the molecular mechanisms underlying its cellular toxicity are not fully understood. Recent findings in yeast cells indicate that cadmium exerts its deleterious effects by inducing widespread misfolding and aggregation of nascent proteins. Here, we discuss this novel mode of toxic heavy metal action and propose a mechanism by which molecular chaperones may reduce the damaging effects of heavy metal ions on protein structures.
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Affiliation(s)
- Markus J Tamás
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30, Gothenburg, Sweden.
| | - Bruno Fauvet
- Department of Plant Molecular Biology, Lausanne University, 1015, Lausanne, Switzerland
| | - Philipp Christen
- Department of Biochemistry, University of Zurich, 8057, Zurich, Switzerland
| | - Pierre Goloubinoff
- Department of Plant Molecular Biology, Lausanne University, 1015, Lausanne, Switzerland
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73
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Coelho MPM, Moreira-de-Sousa C, de Souza RB, Ansoar-Rodríguez Y, Silva-Zacarin ECM, Fontanetti CS. Toxicity evaluation of vinasse and biosolid samples in diplopod midgut: heat shock protein in situ localization. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:22007-22017. [PMID: 28785943 DOI: 10.1007/s11356-017-9754-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 07/10/2017] [Indexed: 06/07/2023]
Abstract
Large amounts of residues generated by agricultural, urban and industrial activities are dumped daily on the soil. This practice deserves special attention because it causes serious environmental problems. This study evaluated the toxic potential of the sugarcane vinasse, a by-product of the sugar-alcohol industry, and the biosolid, a residue produced by wastewater treatment plants, both widely used as fertilizers. The evaluation was performed through bioassays using a typical soil bioindicator, the diplopod Rhinocricus padbergi. The specimens were exposed to soils containing these residues in concentrations that are compatible with the Brazilian regulation for agricultural use. Semi-quantitative immunolabelling analyses of the stress protein HSP70 were performed on the midgut of the studied diplopods. There was a significant increase in the immunolabelling of HSP70 proteins as a response to xenobiotics from both residues, particularly in regions where the function of the cells is the detoxification of the organ (e.g. the hepatic cell layer and specific regions of the epithelium). Higher immunolabelling was observed in the specimens exposed to vinasse in comparison with the biosolid exposure. This demonstrates that the substances in the tested residues had proteotoxic action in the exposed animals and induced a cytoprotective response, which led to higher stress protein immunolabelling. Therefore, caution is needed for the use of such residues in agriculture.
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Affiliation(s)
- Maria Paula Mancini Coelho
- Department of Biology, Biosciences Institute, UNESP (São Paulo State University), Av. 24-A, 1515, Rio Claro, São Paulo, 13506-900, Brazil
| | - Cristina Moreira-de-Sousa
- Department of Biology, Biosciences Institute, UNESP (São Paulo State University), Av. 24-A, 1515, Rio Claro, São Paulo, 13506-900, Brazil
| | - Raphael Bastão de Souza
- Department of Biology, Biosciences Institute, UNESP (São Paulo State University), Av. 24-A, 1515, Rio Claro, São Paulo, 13506-900, Brazil
| | - Yadira Ansoar-Rodríguez
- Department of Biology, Biosciences Institute, UNESP (São Paulo State University), Av. 24-A, 1515, Rio Claro, São Paulo, 13506-900, Brazil
| | | | - Carmem Silvia Fontanetti
- Department of Biology, Biosciences Institute, UNESP (São Paulo State University), Av. 24-A, 1515, Rio Claro, São Paulo, 13506-900, Brazil.
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74
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Jacobson T, Priya S, Sharma SK, Andersson S, Jakobsson S, Tanghe R, Ashouri A, Rauch S, Goloubinoff P, Christen P, Tamás MJ. Cadmium Causes Misfolding and Aggregation of Cytosolic Proteins in Yeast. Mol Cell Biol 2017; 37:e00490-16. [PMID: 28606932 PMCID: PMC5559669 DOI: 10.1128/mcb.00490-16] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 10/05/2016] [Accepted: 05/31/2017] [Indexed: 12/22/2022] Open
Abstract
Cadmium is a highly poisonous metal and is classified as a human carcinogen. While its toxicity is undisputed, the underlying in vivo molecular mechanisms are not fully understood. Here, we demonstrate that cadmium induces aggregation of cytosolic proteins in living Saccharomyces cerevisiae cells. Cadmium primarily targets proteins in the process of synthesis or folding, probably by interacting with exposed thiol groups in not-yet-folded proteins. On the basis of in vitro and in vivo data, we show that cadmium-aggregated proteins form seeds that increase the misfolding of other proteins. Cells that cannot efficiently protect the proteome from cadmium-induced aggregation or clear the cytosol of protein aggregates are sensitized to cadmium. Thus, protein aggregation may contribute to cadmium toxicity. This is the first report on how cadmium causes misfolding and aggregation of cytosolic proteins in vivo The proposed mechanism might explain not only the molecular basis of the toxic effects of cadmium but also the suggested role of this poisonous metal in the pathogenesis of certain protein-folding disorders.
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Affiliation(s)
- Therese Jacobson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Smriti Priya
- Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
| | - Sandeep K Sharma
- Nanotherapeutics and Nanomaterial Toxicology Group, CSIR-Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
| | - Stefanie Andersson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Sofia Jakobsson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Robbe Tanghe
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Arghavan Ashouri
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Sebastien Rauch
- Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Pierre Goloubinoff
- Department of Plant Molecular Biology, Lausanne University, Lausanne, Switzerland
| | - Philipp Christen
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Markus J Tamás
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
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75
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Harrison E, Hall JPJ, Paterson S, Spiers AJ, Brockhurst MA. Conflicting selection alters the trajectory of molecular evolution in a tripartite bacteria-plasmid-phage interaction. Mol Ecol 2017; 26:2757-2764. [PMID: 28247474 PMCID: PMC5655702 DOI: 10.1111/mec.14080] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 02/08/2017] [Accepted: 02/08/2017] [Indexed: 01/21/2023]
Abstract
Bacteria engage in a complex network of ecological interactions, which includes mobile genetic elements (MGEs) such as phages and plasmids. These elements play a key role in microbial communities as vectors of horizontal gene transfer but can also be important sources of selection for their bacterial hosts. In natural communities, bacteria are likely to encounter multiple MGEs simultaneously and conflicting selection among MGEs could alter the bacterial evolutionary response to each MGE. Here, we test the effect of interactions with multiple MGEs on bacterial molecular evolution in the tripartite interaction between the bacterium, Pseudomonas fluorescens, the lytic bacteriophage, SBW25φ2, and conjugative plasmid, pQBR103, using genome sequencing of experimentally evolved bacteria. We show that individually, both plasmids and phages impose selection leading to bacterial evolutionary responses that are distinct from bacterial populations evolving without MGEs, but that together, plasmids and phages impose conflicting selection on bacteria, constraining the evolutionary responses observed in pairwise interactions. Our findings highlight the likely difficulties of predicting evolutionary responses to multiple selective pressures from the observed evolutionary responses to each selective pressure alone. Understanding evolution in complex microbial communities comprising many species and MGEs will require that we go beyond studies of pairwise interactions.
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Affiliation(s)
- Ellie Harrison
- Department of Animal and Plant SciencesUniversity of SheffieldSheffieldS10 2TNUK
| | - James P. J. Hall
- Department of Animal and Plant SciencesUniversity of SheffieldSheffieldS10 2TNUK
| | - Steve Paterson
- Institute of Integrative BiologyUniversity of LiverpoolLiverpoolL69 7ZBUK
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76
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C-phycocyanin from Spirulina maxima as a Green Fluorescent Probe for the Highly Selective Detection of Mercury(II) in Seafood. FOOD ANAL METHOD 2016. [DOI: 10.1007/s12161-016-0759-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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77
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Park HR, Oh R, Wagner P, Panganiban R, Lu Q. New Insights Into Cellular Stress Responses to Environmental Metal Toxicants. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 331:55-82. [PMID: 28325215 DOI: 10.1016/bs.ircmb.2016.10.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Exposures to metal toxicants in the environment disrupt normal physiological functions and have been linked to the development of a myriad of human diseases. While the molecular and cellular mechanisms underlying metal toxicities remain to be fully understood, it is well appreciated that metal toxicants induce cellular stresses and that how cells respond to the stresses plays an important role in metal toxicity. In this review, we focus on how metal exposures induce stresses in the endoplasmic reticulum (ER) to elicit the unfolded protein response (UPR). We document the emerging evidence that induction of ER stress and UPR in the development of human diseases is associated with metal exposures. We also discuss the role of the interplay between ER stress and oxidative stress in metal toxicity. Finally, we review recent advances in functional genomics approaches and discuss how applications of these new tools could help elucidate the molecular mechanisms underlying cellular stresses induced by environmental metal toxicants.
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Affiliation(s)
- H-R Park
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - R Oh
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - P Wagner
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - R Panganiban
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - Q Lu
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States.
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78
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Ropo M, Blum V, Baldauf C. Trends for isolated amino acids and dipeptides: Conformation, divalent ion binding, and remarkable similarity of binding to calcium and lead. Sci Rep 2016; 6:35772. [PMID: 27808109 PMCID: PMC5093913 DOI: 10.1038/srep35772] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 10/03/2016] [Indexed: 12/16/2022] Open
Abstract
We derive structural and binding energy trends for twenty amino acids, their dipeptides, and their interactions with the divalent cations Ca2+, Ba2+, Sr2+, Cd2+, Pb2+, and Hg2+. The underlying data set consists of more than 45,000 first-principles predicted conformers with relative energies up to ~4 eV (~400 kJ/mol). We show that only very few distinct backbone structures of isolated amino acids and their dipeptides emerge as lowest-energy conformers. The isolated amino acids predominantly adopt structures that involve an acidic proton shared between the carboxy and amino function. Dipeptides adopt one of two intramolecular-hydrogen bonded conformations C5 or . Upon complexation with a divalent cation, the accessible conformational space shrinks and intramolecular hydrogen bonding is prevented due to strong electrostatic interaction of backbone and side chain functional groups with cations. Clear correlations emerge from the binding energies of the six divalent ions with amino acids and dipeptides. Cd2+ and Hg2+ show the largest binding energies-a potential correlation with their known high acute toxicities. Ca2+ and Pb2+ reveal almost identical binding energies across the entire series of amino acids and dipeptides. This observation validates past indications that ion-mimicry of calcium and lead should play an important role in a toxicological context.
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Affiliation(s)
- M. Ropo
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
- Department of Physics, Tampere University of Technology, Finland
- COMP, Department of Applied Physics, Aalto University, Finland
| | - V. Blum
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
| | - C. Baldauf
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
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79
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Global Fitness Profiling Identifies Arsenic and Cadmium Tolerance Mechanisms in Fission Yeast. G3-GENES GENOMES GENETICS 2016; 6:3317-3333. [PMID: 27558664 PMCID: PMC5068951 DOI: 10.1534/g3.116.033829] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Heavy metals and metalloids such as cadmium [Cd(II)] and arsenic [As(III)] are widespread environmental toxicants responsible for multiple adverse health effects in humans. However, the molecular mechanisms underlying metal-induced cytotoxicity and carcinogenesis, as well as the detoxification and tolerance pathways, are incompletely understood. Here, we use global fitness profiling by barcode sequencing to quantitatively survey the Schizosaccharomyces pombe haploid deletome for genes that confer tolerance of cadmium or arsenic. We identified 106 genes required for cadmium resistance and 110 genes required for arsenic resistance, with a highly significant overlap of 36 genes. A subset of these 36 genes account for almost all proteins required for incorporating sulfur into the cysteine-rich glutathione and phytochelatin peptides that chelate cadmium and arsenic. A requirement for Mms19 is explained by its role in directing iron–sulfur cluster assembly into sulfite reductase as opposed to promoting DNA repair, as DNA damage response genes were not enriched among those required for cadmium or arsenic tolerance. Ubiquinone, siroheme, and pyridoxal 5′-phosphate biosynthesis were also identified as critical for Cd/As tolerance. Arsenic-specific pathways included prefoldin-mediated assembly of unfolded proteins and protein targeting to the peroxisome, whereas cadmium-specific pathways included plasma membrane and vacuolar transporters, as well as Spt–Ada–Gcn5-acetyltransferase (SAGA) transcriptional coactivator that controls expression of key genes required for cadmium tolerance. Notable differences are apparent with corresponding screens in the budding yeast Saccharomyces cerevisiae, underscoring the utility of analyzing toxic metal defense mechanisms in both organisms.
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80
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Schumacher L, Abbott LC. Effects of methyl mercury exposure on pancreatic beta cell development and function. J Appl Toxicol 2016; 37:4-12. [PMID: 27594070 DOI: 10.1002/jat.3381] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 07/29/2016] [Accepted: 07/31/2016] [Indexed: 12/31/2022]
Abstract
Methyl mercury is an environmental contaminant of worldwide concern. Since the discovery of methyl mercury exposure due to eating contaminated fish as the underlying cause of the Minamata disaster, the scientific community has known about the sensitivity of the developing central nervous system to mercury toxicity. Warnings are given to pregnant women and young children to limit consumption of foods containing methyl mercury to protect the embryonic, fetal and postnatally developing central nervous system. However, evidence also suggests that exposure to methyl mercury or various forms of inorganic mercury may also affect development and function of other organs. Numerous reports indicate a worldwide increase in diabetes, particularly type 2 diabetes. Quite recently, methyl mercury has been shown to have adverse effects on pancreatic beta (β) cell development and function, resulting in insulin resistance and hyperglycemia and may even lead to the development of diabetes. This review discusses possible mechanisms by which methyl mercury exposure may adversely affect pancreatic β cell development and function, and the role that methyl mercury exposure may have in the reported worldwide increase in diabetes, particularly type 2 diabetes. While additional information is needed regarding associations between mercury exposure and specific mechanisms of the pathogenesis of diabetes in the human population, methyl mercury's adverse effects on the body's natural sources of antioxidants suggest that one possible therapeutic strategy could involve supplementation with antioxidants. Thus, it is important that additional investigation be undertaken into the role of methyl mercury exposure and reduced pancreatic β cell function. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Lauren Schumacher
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, TX, 77843-4458, USA
| | - Louise C Abbott
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, TX, 77843-4458, USA
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81
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Carra BJ, Till SN, VanGundy RA, Pike RD, Bebout DC. Group 12 complexes of 2,6-bis([(2-pyridinylmethyl)thio]methyl)pyridine: Synthesis and characterization by X-ray crystallography and proton NMR. Polyhedron 2016. [DOI: 10.1016/j.poly.2015.12.038] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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82
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Dkhil MA, Al-Khalifa MS, Al-Quraishy S, Zrieq R, Abdel Moneim AE. Indigofera oblongifolia mitigates lead-acetate-induced kidney damage and apoptosis in a rat model. DRUG DESIGN DEVELOPMENT AND THERAPY 2016; 10:1847-56. [PMID: 27330278 PMCID: PMC4898036 DOI: 10.2147/dddt.s105511] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
This study was conducted to appraise the protective effect of Indigofera oblongifolia leaf extract on lead acetate (PbAc)-induced nephrotoxicity in rats. PbAc was intraperitoneally injected at a dose of 20 mg/kg body weight for 5 days, either alone or together with the methanol extract of I. oblongifolia (100 mg/kg). Kidney lead (Pb) concentration; oxidative stress markers including lipid peroxidation, nitrite/nitrate, and glutathione (GSH); and antioxidant enzyme activities, namely superoxide dismutase, catalase, GSH peroxidase, and GSH reductase were all determined. The PbAc injection elicited a marked elevation in Pb concentration, lipid peroxidation, and nitrite/nitrate, with a concomitant depletion in GSH content compared with the control and a remarkable decrease in antioxidant enzymes. Oxidant/antioxidant imbalance, Pb accumulation, and histological changes in the kidneys were successfully prevented by the pre-administration of I. oblongifolia extract. In addition, the elevated expression of proapoptotic protein, Bax, in the kidneys of the PbAc-injected rats was reduced as a result of I. oblongifolia pre-administration, while the hitherto reduced expression of the anti-apoptotic protein Bcl-2 was elevated. Based on the current findings, it can be concluded that I. oblongifolia successfully minimizes the deleterious effects in kidney function and histological coherence associated with nephrotoxicity by strengthening the antioxidant defense system, suppressing oxidative stress, and mitigating apoptosis.
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Affiliation(s)
- Mohamed A Dkhil
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia; Department of Zoology and Entomology, Faculty of Science, Helwan University, Cairo, Egypt
| | - Mohamed S Al-Khalifa
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Saleh Al-Quraishy
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Rafat Zrieq
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, University of Hail, Hail, Saudi Arabia
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83
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Akimkulova A, Zhou Y, Zhao X, Liu D. Improving the enzymatic hydrolysis of dilute acid pretreated wheat straw by metal ion blocking of non-productive cellulase adsorption on lignin. BIORESOURCE TECHNOLOGY 2016; 208:110-116. [PMID: 26930032 DOI: 10.1016/j.biortech.2016.02.059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Revised: 02/12/2016] [Accepted: 02/16/2016] [Indexed: 05/08/2023]
Abstract
Eleven salts were selected to screen the possible metal ions for blocking the non-productive adsorption of cellulase onto the lignin of dilute acid pretreated wheat straw. Mg(2+) was screened finally as the promising candidate. The optimal concentration of MgCl2 was 1 mM, but the beneficial action was also dependent on pH, hydrolysis time and cellulase loading. Significant improvement of glucan conversion (19.3%) was observed at low cellulase loading (5 FPU/g solid). Addition of isolated lignins, tannic acid and lignin model compounds to pure cellulose hydrolysis demonstrated that phenolic hydroxyl group (Ph-OH) was the main active site blocked by Mg(2+). The interaction between Mg(2+) and Ph-OH of lignin monomeric moieties followed an order of p-hydroxyphenyl (H)>guaiacyl (G)>syringyl (S). Mg(2+) blocking made the lignin surface less negatively charged, which might weaken the hydrogen bonding and electrostatically attractive interaction between lignin and cellulase enzymes.
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Affiliation(s)
- Ardak Akimkulova
- Institute of Applied Chemistry, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Yan Zhou
- Institute of Applied Chemistry, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Xuebing Zhao
- Institute of Applied Chemistry, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China; Tsinghua Innovation Center in Dongguan, Dongguan 523808, China.
| | - Dehua Liu
- Institute of Applied Chemistry, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China; Tsinghua Innovation Center in Dongguan, Dongguan 523808, China
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84
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Gu Y, Sun X, Liu Y. Biosorption and biodegradation of bisphenol A in an activated sludge system. RESEARCH ON CHEMICAL INTERMEDIATES 2016. [DOI: 10.1007/s11164-015-2274-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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85
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Hara M, Monna S, Murata T, Nakano T, Amano S, Nachbar M, Wätzig H. The Arabidopsis KS-type dehydrin recovers lactate dehydrogenase activity inhibited by copper with the contribution of His residues. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2016; 245:135-42. [PMID: 26940498 DOI: 10.1016/j.plantsci.2016.02.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Revised: 02/05/2016] [Accepted: 02/06/2016] [Indexed: 05/02/2023]
Abstract
Dehydrin, which is one of the late embryogenesis abundant (LEA) proteins, is involved in the ability of plants to tolerate the lack of water. Although many reports have indicated that dehydrins bind heavy metals, the physiological role of this metal binding has not been well understood. Here, we report that the Arabidopsis KS-type dehydrin (AtHIRD11) recovered the lactate dehydrogenase (LDH) activity denatured by Cu(2+). The LDH activity was partially inhibited by 0.93 μM Cu(2+) but totally inactivated by 9.3 μM Cu(2+). AtHIRD11 recovered the activity of LDH treated with 9.3 μM Cu(2+) in a dose-dependent manner. The recovery activity of AtHIRD11 was significantly higher than those of serum albumin and lysozyme. The conversion of His residues to Ala in AtHIRD11 resulted in the loss of the Cu(2+) binding of the protein as well as the disappearance of the conformational change induced by Cu(2+) that is observed by circular dichroism spectroscopy. The mutant protein showed lower recovery activity than the original AtHIRD11. These results indicate that AtHIRD11 can reactivate LDH inhibited by Cu(2+) via the His residues. This function may prevent physiological damage to plants due to heavy-metal stress.
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Affiliation(s)
- Masakazu Hara
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
| | - Shuhei Monna
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan
| | - Takae Murata
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan
| | - Taiyo Nakano
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan
| | - Shono Amano
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan
| | - Markus Nachbar
- Institut für Pharmazeutische Chemie, Technische Universität Braunschweig, Beethovenstraße 55, 38106 Braunschweig, Germany
| | - Hermann Wätzig
- Institut für Pharmazeutische Chemie, Technische Universität Braunschweig, Beethovenstraße 55, 38106 Braunschweig, Germany
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86
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Pan SY, Gao SH, Lin RC, Zhou SF, Dong HG, Tang MK, Yu ZL, Ko KM. New perspectives on dietary-derived treatments and food safety-antinomy in a new era. Crit Rev Food Sci Nutr 2016; 55:1836-59. [PMID: 24915382 DOI: 10.1080/10408398.2011.654286] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Despite the advances in science and technology and wide use of chemical drugs, dietary intervention (or food therapy) remains useful in preventing or treating many human diseases. A huge body of evidence shows that the dietary pattern or habit is also an important contributing factor to the development of chronic diseases such as hypertension, type 2 diabetes, hyperlipidemia, and cancers. In recent years, over-the-counter health foods, nutraceuticals, and plant-derived medicinal products have been gaining popularity all over the world, particularly in developed countries. Unfortunately, owing to the contamination with various harmful substances in foods and the presence of toxic food components, food-borne diseases have also become increasingly problematic. Incidents of food poisonings or tainted food have been increasing worldwide, particularly in China and other developing countries. Therefore, the government should put in a greater effort in enforcing food safety by improving the surveillance mechanism and exerting highest standards of quality control for foods.
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Affiliation(s)
- Si-Yuan Pan
- a Beijing University of Chinese Medicine , Beijing , China
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87
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First-principles data set of 45,892 isolated and cation-coordinated conformers of 20 proteinogenic amino acids. Sci Data 2016; 3:160009. [PMID: 26881946 PMCID: PMC4755128 DOI: 10.1038/sdata.2016.9] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 01/15/2016] [Indexed: 11/24/2022] Open
Abstract
We present a structural data set of the 20 proteinogenic amino acids and their amino-methylated and acetylated (capped) dipeptides. Different protonation states of the backbone (uncharged and zwitterionic) were considered for the amino acids as well as varied side chain protonation states. Furthermore, we studied amino acids and dipeptides in complex with divalent cations (Ca2+, Ba2+, Sr2+, Cd2+, Pb2+, and Hg2+). The database covers the conformational hierarchies of 280 systems in a wide relative energy range of up to 4 eV (390 kJ/mol), summing up to a total of 45,892 stationary points on the respective potential-energy surfaces. All systems were calculated on equal first-principles footing, applying density-functional theory in the generalized gradient approximation corrected for long-range van der Waals interactions. We show good agreement to available experimental data for gas-phase ion affinities. Our curated data can be utilized, for example, for a wide comparison across chemical space of the building blocks of life, for the parametrization of protein force fields, and for the calculation of reference spectra for biophysical applications.
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88
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Warner T, Jalilehvand F. Formation of Hg(II) Tetrathiolate Complexes with Cysteine at Neutral pH. CAN J CHEM 2016; 94:373-379. [PMID: 27064521 DOI: 10.1139/cjc-2015-0375] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mercury(II) ions precipitate from aqueous cysteine (H2Cys) solutions containing H2Cys/Hg(II) mole ratio ≥ 2.0 as Hg(S-HCys)2. In absence of additional cysteine, the precipitate dissolves at pH ~12 with the [Hg(S,N-Cys)2]2- complex dominating. With excess cysteine (H2Cys/Hg(II) mole ratio ≥ 4.0), higher complexes form and the precipitate dissolves at lower pH values. Previously, we found that tetrathiolate [Hg(S-Cys)4]6- complexes form at pH = 11.0; in this work we extend the investigation to pH values of physiological interest. We examined two series of Hg(II)-cysteine solutions in which CHg(II) varied between 8 - 9 mM and 80 - 100 mM, respectively, with H2Cys/Hg(II) mole ratios from 4 to ~20. The solutions were prepared in the pH range 7.1 - 8.8, at the pH at which the initial Hg(S-HCys)2 precipitate dissolved. The variations in the Hg(II) speciation were followed by 199Hg NMR, X-ray absorption and Raman spectroscopic techniques. Our results show that in the dilute solutions (CHg(II) = 8 - 9 mM), mixtures of di-, tri- (major) and tetrathiolate complexes exist at moderate cysteine excess (CH2Cys ~ 0.16 M) at pH 7.1. In the more concentrated solutions (CHg(II) = 80 - 100 mM) with high cysteine excess (CH2Cys > 0.9 M), tetrathiolate [Hg(S-cysteinate)4] m-6 (m = 0 - 4) complexes dominate in the pH range 7.3 - 7.8, with lower charge than for the [Hg(S-Cys)4]6- complex due to protonation of some (m) of the amino groups of the coordinated cysteine ligands. The results of this investigation could provide a key to the mechanism of biosorption and accumulation of Hg(II) ions in biological / environmental systems.
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Affiliation(s)
- Thomas Warner
- Department of Chemistry, University of Calgary, 2500 University Drive, Calgary, Alberta T2N 1N4
| | - Farideh Jalilehvand
- Department of Chemistry, University of Calgary, 2500 University Drive, Calgary, Alberta T2N 1N4
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89
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Liu Y, Xiang Y, Ding D, Guo R. Structural effects of amphiphilic protein/gold nanoparticle hybrid based nanozyme on peroxidase-like activity and silver-mediated inhibition. RSC Adv 2016. [DOI: 10.1039/c6ra23773h] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Structural effects of amphiphilic protein/gold nanoparticle hybrid based nanozyme on peroxidase-like activity and silver-mediated inhibition.
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Affiliation(s)
- Yan Liu
- College of Chemistry and Chemical Engineering
- Yangzhou University
- Yangzhou
- P. R. China
| | - Yinping Xiang
- College of Chemistry and Chemical Engineering
- Yangzhou University
- Yangzhou
- P. R. China
| | - Ding Ding
- College of Chemistry and Chemical Engineering
- Yangzhou University
- Yangzhou
- P. R. China
| | - Rong Guo
- College of Chemistry and Chemical Engineering
- Yangzhou University
- Yangzhou
- P. R. China
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90
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Ahmed A, Malik A, Jagirdar H, Rabbani N, Khan MS, Al-Senaidy AM, Ismael MA. Copper-Induced Inactivation of Camel Liver Glutathione S-Transferase. Biol Trace Elem Res 2016; 169:69-76. [PMID: 26043917 DOI: 10.1007/s12011-015-0388-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 05/26/2015] [Indexed: 10/23/2022]
Abstract
Glutathione S-transferases (GSTs) are multifunctional enzymes and play an important role in detoxification of xenobiotics and protection against oxidative stress. Camel liver glutathione transferase (cGST) was recently isolated and characterized in our lab. In this study, we have evaluated the effect of monovalent, divalent, and trivalent cations on its activity and stability. Cu(++) was found to be the potent inhibitor of GST activity which loses complete activity at 0.5-mM concentration. Other metal ions did not inhibit GST even at higher concentration of 2 mM. GST incubated with Cu(++) (0.1 mM) resulted decrease in free sulfhydryl groups by 55%, whereas other metal ions did not show any effect on free thiol content. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed formation of GST aggregates instantly in the presence of Cu(++), which further increased in molecular size with increase in time of incubation. DTT treatment resulted in de-aggregation of GST oligomers to its monomeric form. However, the GST activity was not recovered completely after de-aggregation. Cu(++) was found to inhibit GST activity by accelerating the inter- and intra-disulfide bond formation. Far-UV circular dichroism (CD) results showed that Cu(++)-catalyzed air oxidation of sulfhydryl groups leads to minor conformational changes in the GST.
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Affiliation(s)
- Anwar Ahmed
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
- Center of Excellence in Biotechnology Research, Department of Biochemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
| | - Ajamaluddin Malik
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Haseeb Jagirdar
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Nayyar Rabbani
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Mohd Shahnawaz Khan
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Abdulrahman M Al-Senaidy
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Mohamed A Ismael
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
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91
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Heavy Metals and Human Health: Mechanistic Insight into Toxicity and Counter Defense System of Antioxidants. Int J Mol Sci 2015; 16:29592-630. [PMID: 26690422 PMCID: PMC4691126 DOI: 10.3390/ijms161226183] [Citation(s) in RCA: 502] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 12/01/2015] [Accepted: 12/03/2015] [Indexed: 02/07/2023] Open
Abstract
Heavy metals, which have widespread environmental distribution and originate from natural and anthropogenic sources, are common environmental pollutants. In recent decades, their contamination has increased dramatically because of continuous discharge in sewage and untreated industrial effluents. Because they are non-degradable, they persist in the environment; accordingly, they have received a great deal of attention owing to their potential health and environmental risks. Although the toxic effects of metals depend on the forms and routes of exposure, interruptions of intracellular homeostasis include damage to lipids, proteins, enzymes and DNA via the production of free radicals. Following exposure to heavy metals, their metabolism and subsequent excretion from the body depends on the presence of antioxidants (glutathione, α-tocopherol, ascorbate, etc.) associated with the quenching of free radicals by suspending the activity of enzymes (catalase, peroxidase, and superoxide dismutase). Therefore, this review was written to provide a deep understanding of the mechanisms involved in eliciting their toxicity in order to highlight the necessity for development of strategies to decrease exposure to these metals, as well as to identify substances that contribute significantly to overcome their hazardous effects within the body of living organisms.
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92
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Schug TT, Blawas AM, Gray K, Heindel JJ, Lawler CP. Elucidating the links between endocrine disruptors and neurodevelopment. Endocrinology 2015; 156:1941-51. [PMID: 25714811 PMCID: PMC5393340 DOI: 10.1210/en.2014-1734] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Recent data indicate that approximately 12% of children in the United States are affected by neurodevelopmental disorders, including attention deficit hyperactivity disorder, learning disorders, intellectual disabilities, and autism spectrum disorders. Accumulating evidence indicates a multifactorial etiology for these disorders, with social, physical, genetic susceptibility, nutritional factors, and chemical toxicants acting together to influence risk. Exposure to endocrine-disrupting chemicals during the early stages of life can disrupt normal patterns of development and thus alter brain function and disease susceptibility later in life. This article highlights research efforts and pinpoints approaches that could shed light on the possible associations between environmental chemicals that act on the endocrine system and compromised neurodevelopmental outcomes.
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Affiliation(s)
- Thaddeus T Schug
- Division of Extramural Research and Training (T.T.S., K.G., J.J.H., C.P.L.), National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709; and Duke University (A.M.B.), Durham, North Carolina 27708
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93
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Chiapello M, Martino E, Perotto S. Common and metal-specific proteomic responses to cadmium and zinc in the metal tolerant ericoid mycorrhizal fungus Oidiodendron maius Zn. Metallomics 2015; 7:805-15. [PMID: 25761960 DOI: 10.1039/c5mt00024f] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Although adaptive metal tolerance may arise in fungal populations in polluted soils, the mechanisms underlying metal-specific tolerance are poorly understood. Comparative proteomics is a powerful tool to identify variation in protein profiles caused by changing environmental conditions, and was used to investigate protein accumulation in a metal tolerant isolate of the ericoid mycorrhizal fungus Oidiodendron maius exposed to zinc and cadmium. Two-dimensional gel electrophoresis and shotgun proteomics followed by mass spectrometry lead to the identification of common and metal-specific proteins and pathways. Proteins selectively induced by cadmium exposure were molecular chaperons of the Hsp90 family, cytoskeletal proteins and components of the translation machinery. Zinc significantly up-regulated metabolic pathways related to energy production and carbohydrates metabolism, likely mirroring zinc adaptation of this fungal isolate. Common proteins induced by the two metal ions were the antioxidant enzyme Cu/Zn superoxide dismutase and ubiquitin. In mycelia exposed to zinc and cadmium, both proteomic techniques also identified agmatinase, an enzyme involved in polyamine biosynthesis. This novel finding suggests that, like plants, polyamines may have important functions in response to abiotic environmental stress in fungi. Genetic evidence also suggests that the biosynthesis of polyamines via an alternative metabolic pathway may be widespread in fungi.
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Affiliation(s)
- M Chiapello
- Department of Life Sciences and Systems Biology, University of Torino, Viale Mattioli 25, 10125, Turin, Italy.
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94
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Early gene expression in Pseudomonas fluorescens exposed to a polymetallic solution. Cell Biol Toxicol 2015; 31:39-81. [DOI: 10.1007/s10565-015-9294-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 02/23/2015] [Indexed: 11/27/2022]
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95
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A novel non-blue laccase from Bacillus amyloliquefaciens: secretory expression and characterization. Int J Biol Macromol 2015; 76:39-44. [PMID: 25709013 DOI: 10.1016/j.ijbiomac.2015.02.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 02/10/2015] [Accepted: 02/12/2015] [Indexed: 11/20/2022]
Abstract
Laccases are copper-containing enzymes which possess a promising potential in many industrial and environmental applications. Here we describe the cloning, extracellular expression and characterization of a novel non-blue laccase from Bacillus amyloliquefaciens in Pichia pastoris. The recombinant enzyme was secreted into the culture supernatant with high activity. It lacks the absorption band at 610 nm typical for blue laccases. However, electron paramagnetic resonance (EPR) spectrum proved the existence of type 1 copper center that was not detectable in the UV-visible spectrum. Metal content analysis revealed that the enzyme contains two copper ions, one iron ion and one zinc ion per protein molecular, suggesting that it is a novel non-blue laccase. The pH and temperature optima of the recombinant laccase were 6.6 and 60°C, respectively, and it was stable at pH 9.0 for 10 days. The enzyme activity was slightly activated by NaCl with concentration up to 200 mM. The purified laccase showed high efficiency in decolorizing reactive black 5 and indigo carmine, achieving more than 93% decolorization after 1h. The extreme robustness of the recombinant B. amyloliquefaciens laccase offers several advantages over most fungal laccases in various industrial applications.
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96
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Functional characterization of a type 3 metallolthionein isoform (OsMTI-3a) from rice. Int J Biol Macromol 2015; 73:154-9. [DOI: 10.1016/j.ijbiomac.2014.10.067] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 10/29/2014] [Accepted: 10/30/2014] [Indexed: 11/22/2022]
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97
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Tinkov AA, Ajsuvakova OP, Skalnaya MG, Popova EV, Sinitskii AI, Nemereshina ON, Gatiatulina ER, Nikonorov AA, Skalny AV. Mercury and metabolic syndrome: a review of experimental and clinical observations. Biometals 2015; 28:231-54. [DOI: 10.1007/s10534-015-9823-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 01/15/2015] [Indexed: 12/16/2022]
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98
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Zhou Q, Wu Z, Huang X, Zhong F, Cai Q. A highly selective fluorescent probe for in vitro and in vivo detection of Hg2+. Analyst 2015; 140:6720-6. [DOI: 10.1039/c5an00452g] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper, a simple fluorescent probe, rhodamine B derivatives (RS), was designed and prepared for sensitive detection of Hg2+ in CH3CN/H2O (5/5, v/v).
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Affiliation(s)
- Quan Zhou
- State Key Laboratory of Chemo/Biosensing and Chemometrics
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - Zeming Wu
- State Key Laboratory of Chemo/Biosensing and Chemometrics
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - Xiaohua Huang
- State Key Laboratory of Chemo/Biosensing and Chemometrics
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - Fenfen Zhong
- State Key Laboratory of Chemo/Biosensing and Chemometrics
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
| | - Qingyun Cai
- State Key Laboratory of Chemo/Biosensing and Chemometrics
- College of Chemistry and Chemical Engineering
- Hunan University
- Changsha
- China
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99
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Zhong B, Mao H, Fan Q, Liu Y, Hu Y, Mi Y, Wu F, Hu C. SiRNA-mediated knockdown of CiGRP78 gene expression leads cell susceptibility to heavy metal cytotoxicity. Gene 2014; 552:219-24. [PMID: 25241386 DOI: 10.1016/j.gene.2014.09.036] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 09/15/2014] [Accepted: 09/16/2014] [Indexed: 11/17/2022]
Abstract
Heavy metal ion is one of the critical environmental pollutants accumulated in living organisms and causes toxic or carcinogenic effects once passed threshold levels. As an important member of Hsp70 (heat shock protein 70) family, the 78-kDa glucose-regulated protein (GRP78) can enhance cell survival rates remarkably under thermal stress. Recent studies also demonstrated that the expression of GRP78 enhances the cell survival under heavy metal stress. In this study, three most representative heavy metal ions, Pb(2+), Hg(2+) and Cd(2+), were used to stimulate Ctenopharyngodon idella kidney (CIK) cells. The results showed that cell viability under Pb(2+), Hg(2+) and Cd(2+) stress decreased significantly. The longer and the greater the concentrations of stimulation from heavy metal ions, the higher the rate of cell death was observed. Among them, Hg(2+) is the most hazardous to cells. Under the same stress condition, Hg(2+) resulted in 50% of cell death, Cd(2+) (or Pb(2+)) led to 45% (or 35%) of cell death, respectively. Western immunoblotting indicated that C. idella GRP78 (CiGRP78) protein expression level was enhanced obviously in CIK cells under Pb(2+), Hg(2+) and Cd(2+) stress, meaning CiGRP78 is involved in heavy metal cytotoxicity. To further study the role of CiGRP78 in cytoprotection, we designed the siRNA against CiGRP78 (from nucleotides +788 to +806) and transfected it into CIK cells to silence endogenous CiGRP78. The viability rate of CIK cells transfected with or without siRNA incubated with HgCl2 for 12h showed a significant decrease from 50% to 21%. Our results showed that CiGRP78 protects cells against heavy metal stimuli to some extent.
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Affiliation(s)
- Bin Zhong
- Department of Bioscience, College of life science, Nanchang University, Nanchang 330031, China
| | - Huiling Mao
- Department of Bioscience, College of life science, Nanchang University, Nanchang 330031, China
| | - Qidi Fan
- Department of Bioscience, College of life science, Nanchang University, Nanchang 330031, China
| | - Yong Liu
- Department of Bioscience, College of life science, Nanchang University, Nanchang 330031, China
| | - Yousheng Hu
- Department of Bioscience, College of life science, Nanchang University, Nanchang 330031, China
| | - Yichuan Mi
- Department of Bioscience, College of life science, Nanchang University, Nanchang 330031, China
| | - Fan Wu
- Department of Bioscience, College of life science, Nanchang University, Nanchang 330031, China
| | - Chengyu Hu
- Department of Bioscience, College of life science, Nanchang University, Nanchang 330031, China.
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100
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Ibstedt S, Sideri TC, Grant CM, Tamás MJ. Global analysis of protein aggregation in yeast during physiological conditions and arsenite stress. Biol Open 2014; 3:913-23. [PMID: 25217615 PMCID: PMC4197440 DOI: 10.1242/bio.20148938] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Protein aggregation is a widespread phenomenon in cells and associated with pathological conditions. Yet, little is known about the rules that govern protein aggregation in living cells. In this study, we biochemically isolated aggregation-prone proteins and used computational analyses to identify characteristics that are linked to physiological and arsenite-induced aggregation in living yeast cells. High protein abundance, extensive physical interactions, and certain structural properties are positively correlated with an increased aggregation propensity. The aggregated proteins have high translation rates and are substrates of ribosome-associated Hsp70 chaperones, indicating that they are susceptible for aggregation primarily during translation/folding. The aggregation-prone proteins are enriched for multiple chaperone interactions, thus high protein abundance is probably counterbalanced by molecular chaperones to allow soluble expression in vivo. Our data support the notion that arsenite interferes with chaperone activity and indicate that arsenite-aggregated proteins might engage in extensive aberrant protein–protein interactions. Expression of aggregation-prone proteins is down-regulated during arsenite stress, possibly to prevent their toxic accumulation. Several aggregation-prone yeast proteins have human homologues that are implicated in misfolding diseases, suggesting that similar mechanisms may apply in disease- and non-disease settings.
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Affiliation(s)
- Sebastian Ibstedt
- Department of Chemistry and Molecular Biology, University of Gothenburg, S-405 30 Gothenburg, Sweden
| | - Theodora C Sideri
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK Current address: Department of Genetics, Evolution and Environment and UCL Cancer Institute, University College London, WC1E 6BT, London, UK
| | - Chris M Grant
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
| | - Markus J Tamás
- Department of Chemistry and Molecular Biology, University of Gothenburg, S-405 30 Gothenburg, Sweden
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