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Sample records for blue copper protein

  1. Functionally specified protein signatures distinctive for each of the different blue copper proteins

    Directory of Open Access Journals (Sweden)

    Anishetty Sharmila

    2004-09-01

    Full Text Available Abstract Background Proteins having similar functions from different sources can be identified by the occurrence in their sequences, a conserved cluster of amino acids referred to as pattern, motif, signature or fingerprint. The wide usage of protein sequence analysis in par with the growth of databases signifies the importance of using patterns or signatures to retrieve out related sequences. Blue copper proteins are found in the electron transport chain of prokaryotes and eukaryotes. The signatures already existing in the databases like the type 1 copper blue, multiple copper oxidase, cyt b/b6, photosystem 1 psaA&B, psaG&K, and reiske iron sulphur protein are not specified signatures for blue copper proteins as the name itself suggests. Most profile and motif databases strive to classify protein sequences into a broad spectrum of protein families. This work describes the signatures designed based on the copper metal binding motifs in blue copper proteins. The common feature in all blue copper proteins is a trigonal planar arrangement of two nitrogen ligands [each from histidine] and one sulphur containing thiolate ligand [from cysteine], with strong interactions between the copper center and these ligands. Results Sequences that share such conserved motifs are crucial to the structure or function of the protein and this could provide a signature of family membership. The blue copper proteins chosen for the study were plantacyanin, plastocyanin, cucumber basic protein, stellacyanin, dicyanin, umecyanin, uclacyanin, cusacyanin, rusticyanin, sulfocyanin, halocyanin, azurin, pseudoazurin, amicyanin and nitrite reductase which were identified in both eukaryotes and prokaryotes. ClustalW analysis of the protein sequences of each of the blue copper proteins was the basis for designing protein signatures or peptides. The protein signatures and peptides identified in this study were designed involving the active site region involving the amino acids

  2. Determination of the Electron Self-Exchange Rates of Blue Copper Proteins by Super-WEFT NMR Spectroscopy

    DEFF Research Database (Denmark)

    Ma, Lixin; Philipp, Else Astrid; Led, Jens J.

    2001-01-01

    Anabaena variabilis plastocyanin, blue copper proteins, electron self-exchange rates, electron transfer, super-WEFT NMR......Anabaena variabilis plastocyanin, blue copper proteins, electron self-exchange rates, electron transfer, super-WEFT NMR...

  3. Preferred sites and pathways for electron transfer in blue copper proteins

    DEFF Research Database (Denmark)

    Farver, O; Pecht, I

    1988-01-01

    Long-range electron transfer reactions proceed within and between metalloproteins at relatively fast rates and with marked specificities. The blue single copper proteins are well known electron carriers with their redox center being of limited accessibility to solvent and solutes. The question......, E.T. proceeds via an extended imidazole ring system, and in plastocyanin and stellacyanin via a weakly coupled pi-system. Therefore, a case emerges for suggesting that this is the common feature of the long-distance intramolecular E.T. in this class of metalloproteins. These pathways are most...

  4. Direct electrochemistry of blue copper proteins at boron-doped diamond electrodes

    Energy Technology Data Exchange (ETDEWEB)

    McEvoy, James P. [Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA (United Kingdom); Foord, John S. [Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA (United Kingdom)]. E-mail: john.foord@chem.ox.ac.uk

    2005-05-05

    Boron-doped diamond (BDD) is a promising electrode material for use in the spectro-electrochemical study of redox proteins and, in this investigation, cyclic voltammetry was used to obtain quasi-reversible electrochemical responses from two blue copper proteins, parsley plastocyanin and azurin from Pseudomonas aeruginosa. No voltammetry was observed at the virgin electrodes, but signals were observed if the electrodes were anodised, or abraded with alumina, prior to use. Plastocyanin, which has a considerable overall negative charge and a surface acidic patch which is important in forming a productive electron transfer complex with its redox partners, gave a faradaic signal at pre-treated BDD only in the presence of neomycin, a positively charged polyamine. The voltammetry of azurin, which has a small overall charge and no surface acidic patch, was obtained identically in the presence and absence of neomycin. Investigations were also carried out into the voltammetry of two site-directed mutants of azurin, M64E azurin and M44K azurin, each of which introduce a charge into the protein's surface hydrophobic patch. The oxidizing and cleaning effects of the BDD electrode pre-treatments were studied electrochemically using two inorganic probe ions, Fe(China){sub 6} {sup 3-} and Ru(NH{sub 3}){sub 6} {sup 3+}, and by X-ray photoelectron spectroscopy (XPS). All of the electrochemical results are discussed in relation to the electrostatic and hydrophobic contributions to the protein/diamond electrochemical interaction.

  5. Metalloproteins diversified: the auracyanins are a family of cupredoxins that stretch the spectral and redox limits of blue copper proteins.

    Science.gov (United States)

    King, Jeremy D; McIntosh, Chelsea L; Halsey, Christopher M; Lada, Bryan M; Niedzwiedzki, Dariusz M; Cooley, Jason W; Blankenship, Robert E

    2013-11-19

    The metal sites of electron transfer proteins are tuned for function. The type 1 copper site is one of the most utilized metal sites in electron transfer reactions. This site can be tuned by the protein environment from +80 mV to +680 mV in typical type 1 sites. Accompanying this huge variation in midpoint potentials are large changes in electronic structure, resulting in proteins that are blue, green, or even red. Here, we report a family of blue copper proteins, the auracyanins, from the filamentous anoxygenic phototroph Chloroflexus aurantiacus that display the entire known spectral and redox variations known in the type 1 copper site. C. aurantiacus encodes four auracyanins, labeled A-D. The midpoint potentials vary from +83 mV (auracyanin D) to +423 mV (auracyanin C). The electronic structures vary from classical blue copper UV-vis absorption spectra (auracyanin B) to highly perturbed spectra (auracyanins C and D). The spectrum of auracyanin C is temperature-dependent. The expansion and divergent nature of the auracyanins is a previously unseen phenomenon.

  6. Blue copper proteins as a model for investigating electron transfer processes within polypeptide matrices

    DEFF Research Database (Denmark)

    Farver, O; Pecht, I

    1994-01-01

    resolution. (3) These proteins have no other cofactors except for the copper ions, thus the role of the polypeptide matrix can be addressed in a more straightforward manner. In azurins, the ET from the cystine (3-26) radical-ion produced by pulse-radiolytic reduction of this single disulfide bridge...

  7. Marked changes in electron transport through the blue copper protein azurin in the solid state upon deuteration

    CERN Document Server

    Amdursky, Nadav; Sheves, Mordechai; Cahen, David

    2012-01-01

    Measuring electron transport (ETp) across proteins in the solid-state offers a way to study electron transfer (ET) mechanism(s) that minimizes solvation effects on the process. Solid state ETp is sensitive to any static (conformational) or dynamic (vibrational) changes in the protein. Our macroscopic measurement technique extends the use of ETp meas-urements down to low temperatures and the concomitant lower current densities, because the larger area still yields measurable currents. Thus, we reported previously a surprising lack of temperature-dependence for ETp via the blue copper protein azurin (Az), from 80K till denaturation, while ETp via apo-(Cu-free) Az was found to be temperature de-pendent \\geq 200K. H/D substitution (deuteration) can provide a potentially powerful means to unravel factors that affect the ETp mechanism at a molecular level. Therefore, we measured and report here the kinetic deuterium isotope effect (KIE) on ETp through holo-Az as a function of temperature (30-340K). We find that deu...

  8. Blue copper protein analogue: synthesis and characterization of copper complexes of the N2S2 macrocycle 1,8-dithia-4,11-diazacyclotetradecane.

    Science.gov (United States)

    Walker, Tia L; Mula, Sam; Malasi, Wilhelm; Engle, James T; Ziegler, Christopher J; van der Est, Art; Modarelli, Jody; Taschner, Michael J

    2015-12-14

    To improve understanding of copper at the active site of Type 1 copper proteins, Cu(I) and Cu(II) complexes of 1,8-dithia-4,11-diazacyclotetradecane, shown in , have been successfully isolated and structurally characterized by X-ray crystallography. In these compounds, both Cu(I) and Cu(II) are centered in the plane of the macrocycle containing two sulphur and two nitrogen heteroatoms comprising the distorted tetrahedral/square planar coordination geometry. The UV/VIS spectra, electrochemistry and EPR properties have been obtained for the Cu(II) complex 2. Three absorption bands at 295 nm, 354 nm, and 545 nm are observed in aqueous solution at a pH of 5. These bands have been assigned to the N → Cu(II) and S → Cu(II) charge transfer bands and the d-d transitions respectively. The Cu(I/II) redox midpoint potential of complex 2 in CH3CN is +403 mV versus NHE.

  9. Ordered Assembly and Controlled Electron Transfer of the Blue Copper Protein Azurin at Gold (111) Single-Crystal Substrates

    DEFF Research Database (Denmark)

    Chi, Qijin; Zhang, Jingdong; Andersen, Jens Enevold Thaulov;

    2001-01-01

    We have shown that Pseudomonas aeruginosa azurin can be immobilized on alkanethiol monolayers self-assembled on Au(111). Immobilization is achieved through hydrophobic interactions between the hydrophobic area around the copper atom in azurin and methyl heads of alkanethiol to form submonolayers...... or monolayers. In this orientation mode azurin molecules on Au(111) are oriented with the redox center (copper atom) facing the electrode surface. This is opposite to the orientation of azurin on bare gold which is via a surface disulfide group such as recently reported. Scanning tunneling microscopy (STM...... (beta) of 1.03 +/- 0.02 per CH2 unit at longer chain lengths. Overvoltage-dependent ET was also examined. The results provide a strategy to ordered molecular assemblies, and controlled orientation and ET of azurin at atomically planar metallic surfaces. This approach can in principle be extended...

  10. Copper and copper proteins in Parkinson's disease.

    Science.gov (United States)

    Montes, Sergio; Rivera-Mancia, Susana; Diaz-Ruiz, Araceli; Tristan-Lopez, Luis; Rios, Camilo

    2014-01-01

    Copper is a transition metal that has been linked to pathological and beneficial effects in neurodegenerative diseases. In Parkinson's disease, free copper is related to increased oxidative stress, alpha-synuclein oligomerization, and Lewy body formation. Decreased copper along with increased iron has been found in substantia nigra and caudate nucleus of Parkinson's disease patients. Copper influences iron content in the brain through ferroxidase ceruloplasmin activity; therefore decreased protein-bound copper in brain may enhance iron accumulation and the associated oxidative stress. The function of other copper-binding proteins such as Cu/Zn-SOD and metallothioneins is also beneficial to prevent neurodegeneration. Copper may regulate neurotransmission since it is released after neuronal stimulus and the metal is able to modulate the function of NMDA and GABA A receptors. Some of the proteins involved in copper transport are the transporters CTR1, ATP7A, and ATP7B and the chaperone ATOX1. There is limited information about the role of those biomolecules in the pathophysiology of Parkinson's disease; for instance, it is known that CTR1 is decreased in substantia nigra pars compacta in Parkinson's disease and that a mutation in ATP7B could be associated with Parkinson's disease. Regarding copper-related therapies, copper supplementation can represent a plausible alternative, while copper chelation may even aggravate the pathology.

  11. Why Do Proteins Glow Blue?

    CERN Document Server

    Sarkar, Sohini; Hazra, Partha; Mandal, Pankaj

    2014-01-01

    Recent literatures reported blue-green emission from amyloid fibril as exclusive signature of fibril formation. This unusual visible luminescence is regularly used to monitor fibril growth. Blue-green emission has also been observed in crystalline protein and in solution. However, the origin of this emission is not known exactly. Our spectroscopic study of serum proteins reveals that the blue-green emission is a property of protein monomer. Evidences suggest that semiconductor-like band structure of proteins with the optical band-gap in the visible region is possibly the origin of this phenomenon. We show here that the band structure of proteins is primarily the result of electron delocalization through the peptide chain, rather than through the hydrogen bond network in secondary structure.

  12. Copper resistance in Pseudomonas syringae mediated by periplasmic and outer membrane proteins.

    OpenAIRE

    Cha, J S; Cooksey, D A

    1991-01-01

    Copper-resistant strains of Pseudomonas syringae pathovar tomato accumulate copper and develop blue colonies on copper-containing media. Three of the protein products of the copper-resistance operon (cop) were characterized to provide an understanding of the copper-resistance mechanism and its relationship to copper accumulation. The Cop proteins, CopA (72 kDa), CopB (39 kDa), and CopC (12 kDa), were produced only under copper induction. CopA and CopC were periplasmic proteins and CopB was an...

  13. Copper and Copper Proteins in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Sergio Montes

    2014-01-01

    Full Text Available Copper is a transition metal that has been linked to pathological and beneficial effects in neurodegenerative diseases. In Parkinson’s disease, free copper is related to increased oxidative stress, alpha-synuclein oligomerization, and Lewy body formation. Decreased copper along with increased iron has been found in substantia nigra and caudate nucleus of Parkinson’s disease patients. Copper influences iron content in the brain through ferroxidase ceruloplasmin activity; therefore decreased protein-bound copper in brain may enhance iron accumulation and the associated oxidative stress. The function of other copper-binding proteins such as Cu/Zn-SOD and metallothioneins is also beneficial to prevent neurodegeneration. Copper may regulate neurotransmission since it is released after neuronal stimulus and the metal is able to modulate the function of NMDA and GABA A receptors. Some of the proteins involved in copper transport are the transporters CTR1, ATP7A, and ATP7B and the chaperone ATOX1. There is limited information about the role of those biomolecules in the pathophysiology of Parkinson’s disease; for instance, it is known that CTR1 is decreased in substantia nigra pars compacta in Parkinson’s disease and that a mutation in ATP7B could be associated with Parkinson’s disease. Regarding copper-related therapies, copper supplementation can represent a plausible alternative, while copper chelation may even aggravate the pathology.

  14. A Plasmodium falciparum copper-binding membrane protein with copper transport motifs

    OpenAIRE

    Choveaux David L; Przyborski Jude M; Goldring JP

    2012-01-01

    Abstract Background Copper is an essential catalytic co-factor for metabolically important cellular enzymes, such as cytochrome-c oxidase. Eukaryotic cells acquire copper through a copper transport protein and distribute intracellular copper using molecular chaperones. The copper chelator, neocuproine, inhibits Plasmodium falciparum ring-to-trophozoite transition in vitro, indicating a copper requirement for malaria parasite development. How the malaria parasite acquires or secretes copper st...

  15. A Plasmodium falciparum copper-binding membrane protein with copper transport motifs

    Directory of Open Access Journals (Sweden)

    Choveaux David L

    2012-11-01

    Full Text Available Abstract Background Copper is an essential catalytic co-factor for metabolically important cellular enzymes, such as cytochrome-c oxidase. Eukaryotic cells acquire copper through a copper transport protein and distribute intracellular copper using molecular chaperones. The copper chelator, neocuproine, inhibits Plasmodium falciparum ring-to-trophozoite transition in vitro, indicating a copper requirement for malaria parasite development. How the malaria parasite acquires or secretes copper still remains to be fully elucidated. Methods PlasmoDB was searched for sequences corresponding to candidate P. falciparum copper-requiring proteins. The amino terminal domain of a putative P. falciparum copper transport protein was cloned and expressed as a maltose binding fusion protein. The copper binding ability of this protein was examined. Copper transport protein-specific anti-peptide antibodies were generated in chickens and used to establish native protein localization in P. falciparum parasites by immunofluorescence microscopy. Results Six P. falciparum copper-requiring protein orthologs and a candidate P. falciparum copper transport protein (PF14_0369, containing characteristic copper transport protein features, were identified in PlasmoDB. The recombinant amino terminal domain of the transport protein bound reduced copper in vitro and within Escherichia coli cells during recombinant expression. Immunolocalization studies tracked the copper binding protein translocating from the erythrocyte plasma membrane in early ring stage to a parasite membrane as the parasites developed to schizonts. The protein appears to be a PEXEL-negative membrane protein. Conclusion Plasmodium falciparum parasites express a native protein with copper transporter characteristics that binds copper in vitro. Localization of the protein to the erythrocyte and parasite plasma membranes could provide a mechanism for the delivery of novel anti-malarial compounds.

  16. Exfoliation of Egyptian Blue and Han Blue, two alkali earth copper silicate-based pigments.

    Science.gov (United States)

    Johnson-McDaniel, Darrah; Salguero, Tina T

    2014-04-24

    In a visualized example of the ancient past connecting with modern times, we describe the preparation and exfoliation of CaCuSi4O10 and BaCuSi4O10, the colored components of the historic Egyptian blue and Han blue pigments. The bulk forms of these materials are synthesized by both melt flux and solid-state routes, which provide some control over the crystallite size of the product. The melt flux process is time intensive, but it produces relatively large crystals at lower reaction temperatures. In comparison, the solid-state method is quicker yet requires higher reaction temperatures and yields smaller crystallites. Upon stirring in hot water, CaCuSi4O10 spontaneously exfoliates into monolayer nanosheets, which are characterized by TEM and PXRD. BaCuSi4O10 on the other hand requires ultrasonication in organic solvents to achieve exfoliation. Near infrared imaging illustrates that both the bulk and nanosheet forms of CaCuSi4O10 and BaCuSi4O10 are strong near infrared emitters. Aqueous CaCuSi4O10 and BaCuSi4O10 nanosheet dispersions are useful because they provide a new way to handle, characterize, and process these materials in colloidal form.

  17. Copper and Copper Proteins in Parkinson’s Disease

    OpenAIRE

    Sergio Montes; Susana Rivera-Mancia; Araceli Diaz-Ruiz; Luis Tristan-Lopez; Camilo Rios

    2014-01-01

    Copper is a transition metal that has been linked to pathological and beneficial effects in neurodegenerative diseases. In Parkinson's disease, free copper is related to increased oxidative stress, alpha-synuclein oligomerization, and Lewy body formation. Decreased copper along with increased iron has been found in substantia nigra and caudate nucleus of Parkinson's disease patients. Copper influences iron content in the brain through ferroxidase ceruloplasmin activity; therefore decreased pr...

  18. Adsorption of blue copper on a natural and electrochemically treated bentonite

    Science.gov (United States)

    Hajjaji, M.; Mountassir, Y.; Benyaich, A.

    2016-03-01

    Kinetics and equilibrium studies of the adsorption of blue copper on a natural (NC) and electrochemically treated (EMC) bentonite, taken in different experimental conditions, were carried out. Changes of the dye uptake versus operating factors were evaluated using response surface methodology (RSM). The kinetics at 5-50 °C and pH EMC kinetics. The NC isotherms were well described by the Langmuir model and the maximum uptake was around 21 mg/g. In the case of EMC, the Freundlich equation was rather fitting. Dye adsorption on both sorbents was a non-spontaneous process (2 EMC. For NC, the clay dose was rather the most important parameter.

  19. Cooperative binding of copper(I) to the metal binding domains in Menkes disease protein

    DEFF Research Database (Denmark)

    Jensen, P Y; Bonander, N; Møller, L B;

    1999-01-01

    We have optimised the overexpression and purification of the N-terminal end of the Menkes disease protein expressed in Escherichia coli, containing one, two and six metal binding domains (MBD), respectively. The domain(s) have been characterised using circular dichroism (CD) and fluorescence...... spectroscopy, and their copper(I) binding properties have been determined. Structure prediction derived from far-UV CD indicates that the secondary structure is similar in the three proteins and dominated by beta-sheet. The tryptophan fluorescence maximum is blue-shifted in the constructs containing two...... and six MBDs relative to the monomer, suggesting more structurally buried tryptophan(s), compared to the single MBD construct. Copper(I) binding has been studied by equilibrium dialysis under anaerobic conditions. We show that the copper(I) binding to constructs containing two and six domains...

  20. Catalytic degradation of methylene blue by biosynthesised copper nanoflowers using F. benghalensis leaf extract.

    Science.gov (United States)

    Agarwal, Meenakshi; Singh Bhadwal, Akhshay; Kumar, Nishant; Shrivastav, Archana; Raj Shrivastav, Braj; Pratap Singh, Manoj; Zafar, Fahmina; Mani Tripathi, Ravi

    2016-10-01

    This study reports the unprecedented, novel and eco-friendly method for the synthesis of three-dimensional (3D) copper nanostructure having flower like morphology using leaf extract of Ficus benghalensis. The catalytic activity of copper nanoflowers (CuNFs) was investigated against methylene blue (MB) used as a modal dye pollutant. Scanning electron micrograph evidently designated 3D appearance of nanoflowers within a size range from 250 nm to 2.5 μm. Energy-dispersive X-ray spectra showed the presence of copper elements in the nanoflowers. Fourier-transform infrared spectra clearly demonstrated the presence of biomolecules which is responsible for the synthesis of CuNFs. The catalytic activity of the synthesised CuNFs was monitored by ultraviolet-visible spectroscopy. The MB was degraded by 72% in 85 min on addition of CuNFs and the rate constant (k) was found to be 0.77 × 10(-3) s(-1). This method adapted for synthesis of CuNFs offers a valuable contribution in the area of nanomaterial synthesis and in water research by suggesting a sustainable and an alternative route for removal of toxic solvents and waste materials.

  1. Catalytic wet peroxide oxidation of azo dye (Direct Blue 15) using solvothermally synthesized copper hydroxide nitrate as catalyst.

    Science.gov (United States)

    Zhan, Yuzhong; Zhou, Xiang; Fu, Bei; Chen, Yiliang

    2011-03-15

    Copper hydroxide nitrate (Cu(2)(OH)(3)NO(3)) was synthesized solvothermally in anhydrous ethanol and characterized by XRD, FTIR, TG-DTA and SEM. The peroxide degradation of an azo dye (Direct Blue 15) on this material was evaluated by examining catalyst loading, initial pH, hydrogen peroxide dosage, initial dye concentration and temperature. The leaching of Cu from the copper hydroxide nitrate during the reaction was also measured. The copper hydroxide nitrate synthesized solvothermally, which was of a novel spherical morphology with complex secondary structures and contained high-dispersed Cu(2)O impurity, showed good performance for oxidation degradation of the azo dye, especially high catalytic activity, high utilization of hydrogen peroxide and a wide pH range, whereas the copper hydroxide nitrate synthesized by the direct reaction of copper nitrate and sodium hydroxide showed low catalytic activity.

  2. Transition-metal prion protein attachment: Competition with copper

    Science.gov (United States)

    Hodak, Miroslav; Bernholc, Jerry

    2012-02-01

    Prion protein, PrP, is a protein capable of binding copper ions in multiple modes depending on their concentration. Misfolded PrP is implicated in a group of neurodegenerative diseases, which include ``mad cow disease'' and its human form, variant Creutzfeld-Jacob disease. An increasing amount of evidence suggests that attachment of non-copper metal ions to PrP triggers transformations to abnormal forms similar to those observed in prion diseases. In this work, we use hybrid Kohn-Sham/orbital-free density functional theory simulations to investigate copper replacement by other transition metals that bind to PrP, including zinc, iron and manganese. We consider all known copper binding modes in the N-terminal domain of PrP. Our calculations identify modes most susceptible to copper replacement and reveal metals that can successfully compete with copper for attachment to PrP.

  3. EXAFS analysis of the pH dependence of the blue-copper site in amicyanin from Thiobacillus versutus.

    Science.gov (United States)

    Lommen, A; Pandya, K I; Koningsberger, D C; Canters, G W

    1991-02-15

    The room temperature Cu K-edge EXAFS (extended X-ray absorption fine structure) spectrum of reduced and oxidized amicyanin, the blue copper protein from Thiobacillus versutus, was measured at low and high pH. The data interpretation was partly based on independent NMR evidence for the occurrence of a ligand histidine protonation at low pH (pKa = 6.9) in the reduced protein. In the oxidized protein two nitrogen-donors (from two histidines; Cu-N distances 1.95-2.01 A and 1.86-1.89 A) and a sulfur-donor (from a cysteine; Cu-S distance 2.11-2.13 A) were identified and the coordination appears independent of pH. Upon reduction at high pH the Cu-S bond and one of the Cu-N bonds lengthen slightly (from 2.11 to 2.19 A and from 2.01 to 2.18 A, respectively). Upon lowering of the pH one of the N-donors of the Cu in reduced amicyanin disappears from the Cu EXAFS and a second S-donor (from a methionine) becomes visible at 2.41 A from the Cu. The Debye-Waller factors are compatible with a Cu-N vibrational stretch frequency in the range of 150-250 cm-1 and one greater than 285 cm-1, and a Cu-S vibrational stretch frequency of about 150 cm-1 (Cu-Smet; reduced amicyanin at low pH) and one in the range of 230-800 cm-1 (Cu-Scys).

  4. Copper Promotes the Trafficking of the Amyloid Precursor Protein*

    OpenAIRE

    Acevedo, Karla M.; Hung, Ya Hui; Dalziel, Andrew H.; Li, Qiao-Xin; Laughton, Katrina; Wikhe, Krutika; Rembach, Alan; Roberts, Blaine; Masters, Colin L.; Ashley I. Bush; Camakaris, James

    2010-01-01

    Accumulation of the amyloid β peptide in the cortical and hippocampal regions of the brain is a major pathological feature of Alzheimer disease. Amyloid β peptide is generated from the sequential protease cleavage of the amyloid precursor protein (APP). We reported previously that copper increases the level of APP at the cell surface. Here we report that copper, but not iron or zinc, promotes APP trafficking in cultured polarized epithelial cells and neuronal cells. In SH-SY5Y neuronal cells ...

  5. Simultaneous Platinum and Copper Ion Attachment to a Human Copper Chaperone Protein

    Science.gov (United States)

    Hodak, Miroslav; Cvitkovic, John; Yu, Corey; Dmitriev, Oleg; Kaminski, George; Bernholc, Jerry

    2015-03-01

    Cisplatin is a potent anti-cancer drug based on a platinum ion. However, its effectiveness is decreased by cellular resistance, which involves cisplatin attaching to copper transport proteins. One of such proteins is Atox1, where cisplatin attaches to the copper binding site. Surprisingly, it was shown that both cisplatin and copper can attach to Atox1 at the same time. To study this double metal ion attachment, we use the KS/FD DFT method, which combines Kohn-Sham DFT with frozen-density DFT to achieve efficient quantum-mechanical description of explicit solvent. Calculations have so far investigated copper ion attachment to CXXC motifs present in Atox1. The addition of the platinum ion and the competition between the two metals is currently being studied. These calculations start from a molecular mechanics (MM) structural model, in which glutathione groups provide additional ligands to the Pt ion. Our goals are to identify possible Cu-Pt structures and to determine whether copper/platinum attachment is competitive, independent, or cooperative. Results will be compared to the 1H, N1 5 -HSQC NMR experiments, in which binding of copper and cisplatin to Atox1 produces distinct secondary chemical shift signatures, allowing for kinetic studies of simultaneous metal binding.

  6. Affinity purification of copper chelating peptides from chickpea protein hydrolysates.

    Science.gov (United States)

    Megías, Cristina; Pedroche, Justo; Yust, Maria M; Girón-Calle, Julio; Alaiz, Manuel; Millan, Francisco; Vioque, Javier

    2007-05-16

    Chickpea protein hydrolysates obtained with alcalase and flavourzyme were used for purification of copper chelating peptides by affinity chromatography using copper immobilized on solid supports. The chelating activity of purified peptides was indirectly measured by the inhibition of beta-carotene oxidation in the presence of copper. Two protein hydrolysates, obtained after 10 and 100 min of hydrolysis, were the most inhibitory of beta-carotene oxidation. Purified copper chelating peptides from these protein hydrolysates contained 19.7 and 35.1% histidine, respectively, in comparison to 2.7 and 2.6% in the protein hydrolysates. Chelating peptides from hydrolysate obtained after 10 min of hydrolysis were the most antioxidative being 8.3 times more antioxidative than the hydrolysate, while chelating peptides purified from protein hydrolysate obtained after 100 min were 3.1 times more antioxidative than its hydrolysate. However, the histidine content was higher in peptides derived from the 100 min hydrolysate (19.7 against 35.1% in 10 min hydrolysate), indicating that this amino acid is not the only factor involved in the antioxidative activity, and other factors such as peptide size or amino acid sequence are also determinant. This manuscript shows that affinity chromatography is a useful procedure for purification of copper chelating peptides. This method can be extended to other metals of interest in nutrition, such as calcium, iron, or zinc. Purified chelating peptides, in addition to their antioxidative properties, may also be useful in food mineral fortification for increasing the bioavailability of these metals.

  7. Placenta Copper Transport Proteins in Preeclampsia

    Science.gov (United States)

    Placental insufficiency underlying preeclampsia (PE) is associated with impaired placental angiogenesis. As copper (Cu) is essential to angiogenesis, we investigated differences in the expression of placental Cu transporters Menkes (ATP7A), Wilsons (ATP7B) and the Cu chaperone (CCS) for superoxide d...

  8. A docking approach to the study of copper trafficking proteins: interaction between metallochaperones and soluble domains of copper ATPases

    NARCIS (Netherlands)

    Arnesano, F.; Banci, L.; Bertini, I.; Bonvin, A.M.J.J.

    2004-01-01

    A structural model of the transient complex between the yeast copper chaperone Atx1 and the first soluble domain of the copper transporting ATPase Ccc2 was obtained with HADDOCK, combining NMR chemical shift mapping information with in silico docking. These two proteins are involved in copper traffi

  9. The Amyloid Precursor Protein of Alzheimer's Disease in the Reduction of Copper(II) to Copper(I)

    Science.gov (United States)

    Multhaup, Gerd; Schlicksupp, Andrea; Hesse, Lars; Beher, Dirk; Ruppert, Thomas; Masters, Colin L.; Beyreuther, Konrad

    1996-03-01

    The transition metal ion copper(II) has a critical role in chronic neurologic diseases. The amyloid precursor protein (APP) of Alzheimer's disease or a synthetic peptide representing its copper-binding site reduced bound copper(II) to copper(I). This copper ion-mediated redox reaction led to disulfide bond formation in APP, which indicated that free sulfhydryl groups of APP were involved. Neither superoxide nor hydrogen peroxide had an effect on the kinetics of copper(II) reduction. The reduction of copper(II) to copper(I) by APP involves an electron-transfer reaction and could enhance the production of hydroxyl radicals, which could then attack nearby sites. Thus, copper-mediated toxicity may contribute to neurodegeneration in Alzheimer's disease.

  10. Low copper and high manganese levels in prion protein plaques

    Science.gov (United States)

    Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

    2013-01-01

    Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

  11. Photoinduced protein modifications by methylene blue and naproxen.

    Science.gov (United States)

    Bracchitta, Giuseppina; Catalfo, Alfio; De Guidi, Guido

    2012-12-01

    HPLC and emission spectroscopy were used to investigate UVA photosensitization of methylene blue (MB) or naproxen (NAP) towards bovine serum albumin (BSA). In addition, time resolved singlet oxygen measurements were carried out. The most stable drug : protein adducts stoichiometry of MB-BSA (1 : 1) and NAP-BSA (9 : 1) were verified by means of binding constant determination. UVA photosensitization of MB or NAP on BSA was studied by monitoring tryptophan (Trp) residue integrity. The sensitized photodegradation of the BSA resulted in different degrees of Trp damage. Thus, protein damage was determined by quantitative measurements of the different Trp (photo)-products. Indeed, many of these Trp derivatives are diagnostic for the photosensitization mechanism and some of them, for the first time in this work, were obtained by UVA photosensitization in proteins. The analysis of quantum yields of the photoproduct distribution allowed to weigh up the type I/II contribution to the UVA photosensitization mechanism. As expected, additional experiments in deuterated solvent resulted in an increase of the photodegradation quantum yields for those species where a singlet oxygen mechanism was involved. The UVA mediated generation of these Trp derivatives is consistent with the occurrence of singlet oxygen formation (almost dominant in MB), and photoionization (significant in NAP) within the protein matrix. Additional experiments at lower NAP concentration, as well as with human serum albumin (which differs for Trp content and, partially, localization), support further the molecular mechanism of photosensitization proposed. The results obtained in the case of this more complex system are in agreement with the free Trp model, even if, in almost all cases, the Trp photoproduct formation quantum yields are lower, due to the higher number of sensitization targets in the proteins.

  12. Combined copper/zinc attachment to prion protein

    Science.gov (United States)

    Hodak, Miroslav; Bernholc, Jerry

    2013-03-01

    Misfolding of prion protein (PrP) is responsible for diseases such as ``mad-cow disease'' in cattle and Creutzfeldt-Jacob in humans. Extensive experimental investigation has established that this protein strongly interacts with copper ions, and this ability has been linked to its still unknown function. Attachment of other metal ions (zinc, iron, manganese) have been demonstrated as well, but none of them could outcompete copper. Recent finding, however, indicates that at intermediate concentrations both copper and zinc ions can attach to the PrP at the octarepeat region, which contains high affinity metal binding sites. Based on this evidence, we have performed density functional theory simulations to investigate the combined Cu/Zn attachment. We consider all previously reported binding modes of copper at the octarepeat region and examine a possibility simultaneous Cu/Zn attachment. We find that this can indeed occur for only one of the known binding sites, when copper changes its coordination mode to allow for attachment of zinc ion. The implications of the simultaneous attachment on neural function remain to be explored.

  13. Effects of Dietary Copper and Zinc Supplementation on Growth Performance, Tissue Mineral Retention, Antioxidant Status, and Fur Quality in Growing-Furring Blue Foxes (Alopex lagopus).

    Science.gov (United States)

    Liu, Zhi; Wu, Xuezhuang; Zhang, Tietao; Guo, Jungang; Gao, Xiuhua; Yang, Fuhe; Xing, Xiumei

    2015-12-01

    A 4×2 factorial experiment with four supplemental levels of copper (0, 20, 40, or 60 mg copper per kg dry matter) from copper sulfate and two supplemental levels of zinc (40 or 200 mg zinc per kg dry matter) from zinc sulfate was conducted to investigate the effects of dietary copper and zinc supplementation on growth performance, tissue mineral retention, antioxidant status, and fur quality in growing-furring blue foxes. One hundred and twenty healthy 15-week-old male blue foxes were randomly allocated to eight dietary treatments with 15 replicates per treatment for a 70-day trial from mid-September to pelting in December. The average daily gain and feed conversion ratio were increased with copper supplementation in the first 35 days as well as the overall period (Pzinc did not affect body gain (P>0.10) and feed intake (P>0.10) but improved feed conversion (Pzinc throughout the experiment. No copper×zinc interaction was observed for growth performance except that a tendency (P=0.09) was found for feed intake in the first 35 days. Supplementation of copper or zinc improved crude fat digestibility (Pzinc addition (Pzinc was affected only by dietary zinc addition (P0.05). However, the level of copper in the liver was increased with copper supplementation (Pzinc supplementation (P=0.08). Dietary zinc addition tended to increase the activity of alkaline phosphatase (P=0.07). The activities of copper-zinc superoxide dismutase and catalase tended to increase by copper (P=0.08) and zinc addition (P=0.05). Moreover, a copper×zinc interaction was observed for catalase in the experiment (Pzinc levels (Pzinc supplementation can improve growth by increasing feed intake and improving fat digestibility. Additionally, copper and zinc can enhance the antioxidant capacity of blue foxes. This study also indicates that additional zinc up to 200 mg/kg did not exert significant adverse effects on the copper metabolism of growing-furring blue foxes.

  14. Crystallization of Ranasmurfin, a blue-coloured protein from Polypedates leucomystax

    Energy Technology Data Exchange (ETDEWEB)

    McMahon, Stephen A. [Centre for Biomolecular Science and The Scottish Structural Proteomics Facility, The University of St Andrews Fife KY16 9RH,Scotland (United Kingdom); Walsh, Martin A. [Medical Research Council France, European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble CEDEX (France); Ching, Rosalind Tan Yan [WestCHEM, Department of Chemistry, University of Glasgow, Glasgow G12 8QQ,Scotland (United Kingdom); Division of Environmental and Evolutionary Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ,Scotland (United Kingdom); Carter, Lester G.; Dorward, Mark; Johnson, Kenneth A.; Liu, Huanting; Oke, Muse [Centre for Biomolecular Science and The Scottish Structural Proteomics Facility, The University of St Andrews Fife KY16 9RH,Scotland (United Kingdom); Bloch, Carlos Jr [Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, Asa Norte, Brasilia 70910-900 (Brazil); Kennedy, Malcolm W. [Division of Environmental and Evolutionary Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ,Scotland (United Kingdom); Latiff, Aishah A. [Doping Control Centre Penang, Universiti Sains Malaysia, 11800 Minden, Penang (Malaysia); Cooper, Alan [WestCHEM, Department of Chemistry, University of Glasgow, Glasgow G12 8QQ,Scotland (United Kingdom); Taylor, Garry L.; White, Malcolm F.; Naismith, James H., E-mail: naismith@st-and.ac.uk [Centre for Biomolecular Science and The Scottish Structural Proteomics Facility, The University of St Andrews Fife KY16 9RH,Scotland (United Kingdom)

    2006-11-01

    A novel blue protein from frog nests has been crystallized. Ranasmurfin, a previously uncharacterized ∼13 kDa blue protein found in the nests of the frog Polypedates leucomystax, has been purified and crystallized. The crystals are an intense blue colour and diffract to 1.51 Å with P2{sub 1} symmetry and unit-cell parameters a = 40.9, b = 59.9, c = 45.0 Å, β = 93.3°. Self-rotation function analysis indicates the presence of a dimer in the asymmetric unit. Biochemical data suggest that the blue colour of the protein is related to dimer formation. Sequence data for the protein are incomplete, but thus far have identified no model for molecular replacement. A fluorescence scan shows a peak at 9.676 keV, indicating that the protein binds zinc and suggesting a route for structure solution.

  15. Origin of the exotic blue color of copper-containing historical pigments.

    Science.gov (United States)

    García-Fernández, Pablo; Moreno, Miguel; Aramburu, José Antonio

    2015-01-05

    The study of chemical factors that influence pigment coloring is a field of fundamental interest that is still dominated by many uncertainties. In this Article, we investigate, by means of ab initio calculations, the origin of the unusual bright blue color displayed by historical Egyptian Blue (CaCuSi4O10) and Han Blue (BaCuSi4O10) pigments that is surprisingly not found in other compounds like BaCuSi2O6 or CaCuO2 containing the same CuO4(6-) chromophore. We show that the differences in hue between these systems are controlled by a large red-shift (up to 7100 cm(-1)) produced by an electrostatic field created by a lattice over the CuO4(6-) chromophore from the energy of the 3z(2)-r(2) → x(2)-y(2) transition, a nonlocal phenomenon widely ignored in the realm of transition metal chemistry and strongly dependent upon the crystal structure. Along this line, we demonstrate that, although SiO4(4-) units are not involved in the chromophore itself, the introduction of sand to create CaCuSi4O10 plays a key role in obtaining the characteristic hue of the Egyptian Blue pigment. The results presented here demonstrate the opportunity for tuning the properties of a given chromophore by modifying the structure of the insulating lattice where it is located.

  16. Serum Copper and Plasma Protein Status in Normal Pregnancy

    Directory of Open Access Journals (Sweden)

    Nushrat Noor, Nasim Jahan, Nayma Sultana

    2012-12-01

    Full Text Available AbstractBackground: Gradual alteration of serum copper and some plasma protein levels may occur with advancement of pregnancy, which is associated with increased maternal and infant morbidity and mortality.Objective: To observe serum copper and plasma protein levels in normal pregnant women of different trimesters in order to find out their nutritional status.Methods: This cross sectional study was carried out in the Department of Physiology, Sir Salimullah Medical College (SSMC, Dhaka, between 1st January 2010 and December 2010. Ninety normal pregnant women of different trimesters with age 20-30 years were included in the study group. They were selected from Out Patient Department of Obstetrics and Gynaecology, SSMC. Age matched 30 non-pregnant women were taken as control. Serum copper level was measured by Spectrophotometric method, serum total protein and albumin levels were estimated by standard method. Statistical analysis was done by one way ANOVA, Bonferroni and Pearson’s correlation coefficient test as applicable.Results: Serum Cu levels were significantly higher in all trimesters of pregnant women compared to control. Again, this value was significantly higher in 3rd trimester than that of in 1st and 2nd trimester and also in 2nd trimester than that of in 1st trimester. In addition, mean serum total protein level was significantly lower in 3rd trimester than control but no statistically significant difference was observed among different trimesters. Again, mean serum albumin level was significantly lower in 2nd and 3rd trimester than 1st trimester and control. In addition, serum Cu concentration showed significant positive correlation with different trimesters of gestation.Conclusion: This study reveals that hypercupremia along with hypoproteinemia occur in pregnant women from 1st to 3rd trimester of gestation. This gradual alteration of micro and macronutrients become more profound with advancement of pregnancy.

  17. Enhanced methylene blue oxidative removal by copper electrode-based plasma irradiation with the addition of hydrogen peroxide.

    Science.gov (United States)

    Son, Guntae; Kim, Do-Hyung; Lee, Jung Seok; Lee, Hongshin

    2016-08-01

    Submerged plasma irradiation (SPI)-based advanced oxidation processes have been studied for the oxidation of recalcitrant organic compounds because of their various physical and chemical properties. However, SPI technologies still have a few drawbacks such as relatively low efficiency for wastewater treatment and high energy consumption. In order to overcome these drawbacks, in this study, we proposed the combination of SPI and the Cu(II)-catalyzed Fenton-like system. The removal of methylene blue (MB) by the SPI system was significantly enhanced upon the addition of H2O2. The pseudo-first-order rate constants of MB removal increased with the increase of applied voltage. In addition, the optimum H2O2 dose and initial solution pH were 100 mM and 9, respectively. The reactive oxidants responsible for MB removal in copper electrode-based SPI/H2O2 systems are likely to be hydroxyl radicals (OH) or cupryl ion (Cu(III)), wherein Cu(III) is especially important. Furthermore, the copper electrode-based SPI/H2O2 system is a novel advanced oxidation process capable of oxidizing water recalcitrant and toxic organic pollutants at neutral pH.

  18. Affi-gel blue treatment simplifies the protein composition of sarcoplasmic reticulum vesicles.

    Science.gov (United States)

    Papp, S; Dux, L; Martonosi, A

    1986-04-01

    Sarcoplasmic reticulum vesicles isolated by conventional techniques usually contain, in addition to the recognized sarcoplasmic reticulum components, several other proteins (phosphorylase, myosin, glyceraldehyde-3-phosphate dehydrogenase, etc.) in variable amounts; these proteins complicate the interpretation of chemical modification data. Incubation of sarcoplasmic reticulum vesicles with Affi-Gel blue particles for 1-4 h at 2 degrees C, followed by sedimentation of the Affi-Gel in a clinical centrifuge, simplifies the protein composition by selective adsorption of the accessory proteins, and improves the consistency of the preparations. The Affi-Gel blue treatment is recommended as part of the standard procedure for the isolation of sarcoplasmic reticulum vesicles.

  19. Highly efficient visual detection of trace copper(II) and protein by the quantum photoelectric effect.

    Science.gov (United States)

    Wang, Peng; Lei, Jianping; Su, Mengqi; Liu, Yueting; Hao, Qing; Ju, Huangxian

    2013-09-17

    This work presented a photocurrent response mechanism of quantum dots (QDs) under illumination with the concept of a quantum photoelectric effect. Upon irradiation, the photoelectron could directly escape from QDs. By using nitro blue tetrazolium (NBT) to capture the photoelectron, a new visual system was proposed due to the formation of an insoluble reduction product, purple formazan, which could be used to visualize the quantum photoelectric effect. The interaction of copper(II) with QDs could form trapping sites to interfere with the quantum confinement and thus blocked the escape of photoelectron, leading to a "signal off" visual method for sensitive copper(II) detection. Meanwhile, by using QDs as a signal tag to label antibody, a "signal on" visual method was also proposed for immunoassay of corresponding protein. With meso-2,3-dimercaptosuccinic-capped CdTe QDs and carcino-embryonic antigen as models, the proposed visual detection methods showed high sensitivity, low detection limit, and wide detectable concentration ranges. The visualization of quantum photoelectric effect could be simply extended for the detection of other targets. This work opens a new visual detection way and provides a highly efficient tool for bioanalysis.

  20. In Absence of the Cellular Prion Protein, Alterations in Copper Metabolism and Copper-Dependent Oxidase Activity Affect Iron Distribution.

    Science.gov (United States)

    Gasperini, Lisa; Meneghetti, Elisa; Legname, Giuseppe; Benetti, Federico

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defined mechanisms. Prion protein, for instance, interacts with divalent cations via multiple metal-binding sites and it modulates several metal-dependent physiological functions, such as S-nitrosylation of NMDA receptors. In this work we focused on the effect of prion protein absence on copper and iron metabolism during development and adulthood. In particular, we investigated copper and iron functional values in serum and several organs such as liver, spleen, total brain and isolated hippocampus. Our results show that iron content is diminished in prion protein-null mouse serum, while it accumulates in liver and spleen. Our data suggest that these alterations can be due to impairments in copper-dependent cerulopalsmin activity which is known to affect iron mobilization. In prion protein-null mouse total brain and hippocampus, metal ion content shows a fluctuating trend, suggesting the presence of homeostatic compensatory mechanisms. However, copper and iron functional values are likely altered also in these two organs, as indicated by the modulation of metal-binding protein expression levels. Altogether, these results reveal that the absence of the cellular prion protein impairs copper metabolism and copper-dependent oxidase activity, with ensuing alteration of iron mobilization from cellular storage compartments.

  1. In Absence of the Cellular Prion Protein, Alterations in Copper Metabolism and Copper-Dependent Oxidase Activity Affect Iron Distribution

    Science.gov (United States)

    Gasperini, Lisa; Meneghetti, Elisa; Legname, Giuseppe; Benetti, Federico

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defined mechanisms. Prion protein, for instance, interacts with divalent cations via multiple metal-binding sites and it modulates several metal-dependent physiological functions, such as S-nitrosylation of NMDA receptors. In this work we focused on the effect of prion protein absence on copper and iron metabolism during development and adulthood. In particular, we investigated copper and iron functional values in serum and several organs such as liver, spleen, total brain and isolated hippocampus. Our results show that iron content is diminished in prion protein-null mouse serum, while it accumulates in liver and spleen. Our data suggest that these alterations can be due to impairments in copper-dependent cerulopalsmin activity which is known to affect iron mobilization. In prion protein-null mouse total brain and hippocampus, metal ion content shows a fluctuating trend, suggesting the presence of homeostatic compensatory mechanisms. However, copper and iron functional values are likely altered also in these two organs, as indicated by the modulation of metal-binding protein expression levels. Altogether, these results reveal that the absence of the cellular prion protein impairs copper metabolism and copper-dependent oxidase activity, with ensuing alteration of iron mobilization from cellular storage compartments. PMID:27729845

  2. Copper binding to the Alzheimer’s disease amyloid precursor protein

    OpenAIRE

    Kong, Geoffrey K.-W.; Miles, Luke A.; Crespi, Gabriela A. N.; Morton, Craig J.; Ng, Hooi Ling; Barnham, Kevin J.; McKinstry, William J.; Cappai, Roberto; Michael W. Parker

    2007-01-01

    Alzheimer’s disease is the fourth biggest killer in developed countries. Amyloid precursor protein (APP) plays a central role in the development of the disease, through the generation of a peptide called Aβ by proteolysis of the precursor protein. APP can function as a metalloprotein and modulate copper transport via its extracellular copper binding domain (CuBD). Copper binding to this domain has been shown to reduce Aβ levels and hence a molecular understanding of the interaction between me...

  3. Construction and characterization of an azurin analog for the purple copper site in cytochrome c oxidase.

    OpenAIRE

    Hay, M; Richards, J. H.; Lu, Y.

    1996-01-01

    A protein analog of a purple copper center has been constructed from a recombinant blue copper protein (Pseudomonas aeruginosa azurin) by replacing the loop containing the three ligands to the blue copper center with the corresponding loop of the CuA center in cytochrome c oxidase (COX) from Paracoccus denitrificans. The electronic absorption in the UV and visible region (UV-vis) and electron paramagnetic resonance (EPR) spectra of this analog are remarkably similar to those of the native CuA...

  4. Copper transportion of WD protein in hepatocytes from Wilson disease patients in vitro

    Institute of Scientific and Technical Information of China (English)

    Guo-Qing Hou; Xiu-Ling Liang; Rong Chen; Li-Wen Tang; Ying Wang; Ping-Yi Xu; Ying-Ru Zhang; Cui-Hua Ou

    2001-01-01

    AIM: To study the effect of copper transporting P-type ATPase in copper metabolism of hepatocyte and pathogenesis of Wilson disease (WD). METHODS: WD copper transporting properties in some organelles of the cultured hepatocytes were studied from WD patients and normal controls. These cultured hepatocytes were incubated in the media of copper 15mg.L-1 only, copper 15 mg. L-1 with vincristine (agonist of P-type ArPase) 0.5mg. L-1, or copper 15 mg. L-1 withvanadate (antagonist of P-type ATPase) 18.39 mg. L-1separately. Microsome (endoplasmic reticulum and Golgi apparatus), lysosome, mitochondria, and cytosol were isolated by differential centrifugation. Copper contents in these organelles were measured with atomic absorption spectrophotometer, and the influence in copper transportion of these organelles by vanadate and vincristine were comparatively analyzed between WD patients and controls.WD copper transporting P-type ATPase was detected by SDS-PAGE in conjunction with Western blot in liver samples of WD patients and controls. RESULTS: The specific WD proteins (Mr155 000 lanes) were expressed in human hepatocytes, including the control and WD patients. After incubation with medium containing copper for 2 h or 24 h, the microsome copper concentration in WD patients was obviously lower than that of controls,and the addtion of vanadate or vincristine would change the copper transporting of microsomes obviously. When incubated with vincristine, levels of copper in microsome were significantly increased, while incubated with vanadate,the copper concentrations in microsome were obviously decreased. The results indicated that there were Wdproteins, the copper transportion P-type ATPase in the microsome of hepatocytes. WD patients possessed abnormal copper transporting function of WD protein in the microsome, and the agonist might correct the defect of copper transportion by promoting the activity of copper transportion P-type ATPase. CONCLUSION: Copper transportion P

  5. Dynamic multibody protein interactions suggest versatile pathways for copper trafficking.

    Science.gov (United States)

    Keller, Aaron M; Benítez, Jaime J; Klarin, Derek; Zhong, Linghao; Goldfogel, Matthew; Yang, Feng; Chen, Tai-Yen; Chen, Peng

    2012-05-30

    As part of intracellular copper trafficking pathways, the human copper chaperone Hah1 delivers Cu(+) to the Wilson's Disease Protein (WDP) via weak and dynamic protein-protein interactions. WDP contains six homologous metal binding domains (MBDs) connected by flexible linkers, and these MBDs all can receive Cu(+) from Hah1. The functional roles of the MBD multiplicity in Cu(+) trafficking are not well understood. Building on our previous study of the dynamic interactions between Hah1 and the isolated fourth MBD of WDP, here we study how Hah1 interacts with MBD34, a double-domain WDP construct, using single-molecule fluorescence resonance energy transfer (smFRET) combined with vesicle trapping. By alternating the positions of the smFRET donor and acceptor, we systematically probed Hah1-MBD3, Hah1-MBD4, and MBD3-MBD4 interaction dynamics within the multidomain system. We found that the two interconverting interaction geometries were conserved in both intermolecular Hah1-MBD and intramolecular MBD-MBD interactions. The Hah1-MBD interactions within MBD34 are stabilized by an order of magnitude relative to the isolated single-MBDs, and thermodynamic and kinetic evidence suggest that Hah1 can interact with both MBDs simultaneously. The enhanced interaction stability of Hah1 with the multi-MBD system, the dynamic intramolecular MBD-MBD interactions, and the ability of Hah1 to interact with multiple MBDs simultaneously suggest an efficient and versatile mechanism for the Hah1-to-WDP pathway to transport Cu(+).

  6. Inhibition of Hsp70 by Methylene Blue Affects Signaling Protein Function and Ubiquitination and Modulates Polyglutamine Protein Degradation*

    OpenAIRE

    Wang, Adrienne M; Morishima, Yoshihiro; Clapp, Kelly M.; Peng, Hwei-Ming; Pratt, William B.; Gestwicki, Jason E.; Osawa, Yoichi; Lieberman, Andrew P.

    2010-01-01

    The Hsp90/Hsp70-based chaperone machinery regulates the activity and degradation of many signaling proteins. Cycling with Hsp90 stabilizes client proteins, whereas Hsp70 interacts with chaperone-dependent E3 ubiquitin ligases to promote protein degradation. To probe these actions, small molecule inhibitors of Hsp70 would be extremely useful; however, few have been identified. Here we test the effects of methylene blue, a recently described inhibitor of Hsp70 ATPase activity, in three well est...

  7. Affi-Gel Blue for nucleic acid removal and early enrichment of nucleotide binding proteins.

    Science.gov (United States)

    Deutscher, Murray P

    2009-01-01

    Passage of an extract or supernatant fraction through a column of Affi-Gel Blue and batchwise elution can be a rapid and effective early procedure for removal of nucleic acid, concentration of the sample and purification of nucleotide binding proteins.

  8. Separation of metalloproteins using a novel metal ion contaminant sweeping technique and detection of protein-bound copper by a metal ion probe in polyacrylamide gel electrophoresis: distribution of copper in human serum.

    Science.gov (United States)

    Saito, Shingo; Kawashima, Mitsuyoshi; Ohshima, Hiroki; Enomoto, Kazuki; Sato, Makoto; Yoshimura, Hajime; Yoshimoto, Keitaro; Maeda, Mizuo; Shibukawa, Masami

    2013-10-21

    A polyacrylamide gel electrophoresis (PAGE)-based method has been developed, consisting of two types of gel electrophoresis, to obtain an accurate distribution of protein-bound metal ions in biological samples. First, proteins are separated by PAGE without the uptake of contaminant metal ions in the separation field and dissociation of metal ions from the proteins. This is followed by another PAGE for the separation and detection of protein-bound metal ions in small volume samples with high sensitivity in the ppt range using a fluorescent metal probe. The former is a new technique using blue-native (BN) PAGE to electrophoretically sweep all metal contaminants by employing two kinds of chelating agents. These agents form complexes with contaminants in the gel and the separation buffer solution, which migrate towards opposite pole directions, thus lowering the contaminants to below the ppt level during separation. This is termed "Metal Ion Contaminant Sweeping BN-PAGE (MICS-BN-PAGE)". After the separation of proteins under these first metal-free conditions, the metal ions in the gel fractions are eluted, followed by derivatization of copper ions into the metal probe complexes to be separated and determined by fluorescence detection in the second PAGE. In this PAGE-based method, the copper ions bound to ceruloplasmin and superoxide dismutase were quantitatively determined, in addition to the exchangeable albumin-bound copper ions. This system successfully provided distribution maps of protein-copper in human serum. The precise distribution of copper in human serum was investigated, and found to be different from that which is widely accepted.

  9. Food choice by Blue-gray Tanagers in relation to protein content.

    Science.gov (United States)

    Bosque, Carlos; Calchi, Rosanna

    2003-06-01

    We tested discriminatory ability and food choice in relation to protein content of the diet in wild-caught Blue-gray Tanagers (Thraupis episcopus), a generalist tropical frugivorous bird. In two sets of experiments we offered to five individual birds in pair-wise choice trials two nearly iso-caloric experimental diets differing in their protein content only. Protein contents of the experimental diets were 4.6 vs. 1.4% in the first experiment and 3.2 and 1.5% (dry matter basis) in the second experiment. Response varied among individual tanagers, but 6 of the 10 birds showed a clear preference for the food highest in protein. Two individuals displayed a strong positional preference. When testing each treatment group, birds ate daily significantly more of the food that had higher protein content. We conclude that Blue-gray Tanagers prefer richer nitrogen foods. Our results also demonstrate that Blue-gray Tanagers have remarkable discriminatory abilities, they reacted to differences in protein content as small as 0.09% fresh matter. We show for the first time discriminatory ability and preference of wild frugivorous birds for foods richer in protein under controlled conditions. Our findings support the hypothesis that frugivorous birds can act as selective agents for fruit pulp composition.

  10. Studies on the proteins of mass-cultivated, blue-green alga (Spirulina platensis)

    Energy Technology Data Exchange (ETDEWEB)

    Annusuyadevi, M.; Subbulakshmi, G.; Madhair' devi, K.; Venkalaramein, L.V.

    1981-05-01

    The characteristics of the protein of fresh-water, mass-cultured Spirulina platensis have been studied. The solubility of this algal protein in water and various aqueous solvents has been estimated. The total protein content of the blue-green algae was approximately 50-55% of which nearly 9.9% was nonprotein nitrogen. About 80% of the total protein nitrogen can be extracted by three successive extractions with water. Ths isoelectric point of this algal protein is found to be 3.0. The total proteins were characterized physicochemically by standard techniques. In the ultracentrifuge total proteins resolve into two major components with S20w values of 2.6 and 4.7 S. The polyacrylamide gel electrophoretic pattern of the total protein showed seven bands including three prominent ones. The in vitro digestibility of the total protein of fresh algae was found to be 85% when assayed with a pepsin-pancreatin system.

  11. Inhibition of hsp70 by methylene blue affects signaling protein function and ubiquitination and modulates polyglutamine protein degradation.

    Science.gov (United States)

    Wang, Adrienne M; Morishima, Yoshihiro; Clapp, Kelly M; Peng, Hwei-Ming; Pratt, William B; Gestwicki, Jason E; Osawa, Yoichi; Lieberman, Andrew P

    2010-05-21

    The Hsp90/Hsp70-based chaperone machinery regulates the activity and degradation of many signaling proteins. Cycling with Hsp90 stabilizes client proteins, whereas Hsp70 interacts with chaperone-dependent E3 ubiquitin ligases to promote protein degradation. To probe these actions, small molecule inhibitors of Hsp70 would be extremely useful; however, few have been identified. Here we test the effects of methylene blue, a recently described inhibitor of Hsp70 ATPase activity, in three well established systems of increasing complexity. First, we demonstrate that methylene blue inhibits the ability of the purified Hsp90/Hsp70-based chaperone machinery to enable ligand binding by the glucocorticoid receptor and show that this effect is due to specific inhibition of Hsp70. Next, we establish that ubiquitination of neuronal nitric-oxide synthase by the native ubiquitinating system of reticulocyte lysate is dependent upon both Hsp70 and the E3 ubiquitin ligase CHIP and is blocked by methylene blue. Finally, we demonstrate that methylene blue impairs degradation of the polyglutamine expanded androgen receptor, an Hsp90 client mutated in spinal and bulbar muscular atrophy. In contrast, degradation of an amino-terminal fragment of the receptor, which lacks the ligand binding domain and, therefore, is not a client of the Hsp90/Hsp70-based chaperone machinery, is enhanced through homeostatic induction of autophagy that occurs when Hsp70-dependent proteasomal degradation is inhibited by methylene blue. Our data demonstrate the utility of methylene blue in defining Hsp70-dependent functions and reveal divergent effects on polyglutamine protein degradation depending on whether the substrate is an Hsp90 client.

  12. The Copper Metabolism MURR1 Domain protein 1 (COMMD1) modulates the aggregation of misfolded protein species in a client-specific manner

    NARCIS (Netherlands)

    W.I.M. Vonk (Willianne I.); V. Kakkar (Vaishali); P. Bartuzi (Paulina); D. Jaarsma (Dick); R. Berger (Ruud); M.A. Hofker (Marten); L.W.J. Klomp (Leo W.); C. Wijmenga (Cisca); H. Kampinga (Harm); B. van de Sluis (Bart)

    2014-01-01

    textabstractThe Copper Metabolism MURR1 domain protein 1 (COMMD1) is a protein involved in multiple cellular pathways, including copper homeostasis, NF-κB and hypoxia signalling. Acting as a scaffold protein, COMMD1 mediates the levels, stability and proteolysis of its substrates (e.g. the copper-tr

  13. The Copper Metabolism MURR1 Domain Protein 1 (COMMD1) Modulates the Aggregation of Misfolded Protein Species in a Client-Specific Manner

    NARCIS (Netherlands)

    Vonk, Willianne I. M.; Kakkar, Vaishali; Bartuzi, Paulina; Jaarsma, Dick; Berger, Ruud; Hofker, Marten H.; Klomp, Leo W. J.; Wijmenga, Cisca; Kampinga, Harm H.; van de Sluis, Bart

    2014-01-01

    The Copper Metabolism MURR1 domain protein 1 (COMMD1) is a protein involved in multiple cellular pathways, including copper homeostasis, NF-kappa B and hypoxia signalling. Acting as a scaffold protein, COMMD1 mediates the levels, stability and proteolysis of its substrates (e.g. the copper-transport

  14. The Arabidopsis COPT6 transport protein functions in copper distribution under copper-deficient conditions.

    Science.gov (United States)

    Garcia-Molina, Antoni; Andrés-Colás, Nuria; Perea-García, Ana; Neumann, Ulla; Dodani, Sheel C; Huijser, Peter; Peñarrubia, Lola; Puig, Sergi

    2013-08-01

    Copper (Cu), an essential redox active cofactor, participates in fundamental biological processes, but it becomes highly cytotoxic when present in excess. Therefore, living organisms have established suitable mechanisms to balance cellular and systemic Cu levels. An important strategy to maintain Cu homeostasis consists of regulating uptake and mobilization via the conserved family of CTR/COPT Cu transport proteins. In the model plant Arabidopsis thaliana, COPT1 protein mediates root Cu acquisition, whereas COPT5 protein functions in Cu mobilization from intracellular storage organelles. The function of these transporters becomes critical when environmental Cu bioavailability diminishes. However, little is know about the mechanisms that mediate plant Cu distribution. In this report, we present evidence supporting an important role for COPT6 in Arabidopsis Cu distribution. Similarly to COPT1 and COPT2, COPT6 fully complements yeast mutants defective in high-affinity Cu uptake and localizes to the plasma membrane of Arabidopsis cells. Whereas COPT2 mRNA is only up-regulated upon severe Cu deficiency, COPT6 transcript is expressed under Cu excess conditions and displays a more gradual increase in response to decreases in environmental Cu levels. Consistent with COPT6 expression in aerial vascular tissues and reproductive organs, copt6 mutant plants exhibit altered Cu distribution under Cu-deficient conditions, including increased Cu in rosette leaves but reduced Cu levels in seeds. This altered Cu distribution is fully rescued when the wild-type COPT6 gene is reintroduced into the copt6 mutant line. Taken together, these findings highlight the relevance of COPT6 in shoot Cu redistribution when environmental Cu is limited.

  15. Mild copper deficiency alters gene expression of proteins involved in iron metabolism.

    Science.gov (United States)

    Auclair, Sylvain; Feillet-Coudray, Christine; Coudray, Charles; Schneider, Susanne; Muckenthaler, Martina U; Mazur, Andrzej

    2006-01-01

    Iron and copper homeostasis share common proteins and are therefore closely linked to each other. For example, copper-containing proteins like ceruloplasmin and hephaestin oxidize Fe(2+) during cellular export processes for transport in the circulation bound to transferrin. Indeed, copper deficiency provokes iron metabolism disorders leading to anemia and liver iron accumulation. The aim of the present work was to understand the cross-talk between copper status and iron metabolism. For this purpose we have established dietary copper deficiency in C57BL6 male mice during twelve weeks. Hematological parameters, copper and iron status were evaluated. cDNA microarray studies were performed to investigate gene expression profiles of proteins involved in iron metabolism in the liver, duodenum and spleen. Our results showed that copper deficiency induces microcytic and hypochromic anemia as well as liver iron overload. Gene expression profiles, however, indicate that hepatic and intestinal mRNA expression neither compensates for hepatic iron overload nor the anemia observed in this mouse model. Instead, major modifications of gene expression occurred in the spleen. We observed increased mRNA levels of the transferrin receptors 1 and 2 and of several proteins involved in the heme biosynthesis pathway (ferrochelatase, UroD, UroS,...). These results suggest that copper-deficient mice respond to the deficiency induced anemia by an adaptation leading to an increase in erythrocyte synthesis.

  16. Predictive association of copper metabolism proteins with Alzheimer's disease and Parkinson's disease: a preliminary perspective.

    Science.gov (United States)

    Pal, Amit; Kumar, Ashok; Prasad, Rajendra

    2014-02-01

    Neurodegenerative diseases, Alzheimer's disease (AD) and Parkinson's disease (PD), constitute a major worldwide health problem. Several hypothesis have been put forth to elucidate the basis of onset and pathogenesis of AD and PD; however, till date, none of these seems to clearly elucidate the complex pathoetiology of these disorders. Notably, copper dyshomeostasis has been shown to underlie the pathophysiology of several neurodegenerative diseases including AD and PD. Numerous studies have concluded beyond doubt that imbalance in copper homeostatic mechanisms in conjunction with aging causes an acceleration in the copper toxicity elicited oxidative stress, which is detrimental to the central nervous system. Amyloid precursor protein and α-synuclein protein involved in AD and PD are copper binding proteins, respectively. In this review, we have discussed the possible association of copper metabolism proteins with AD and PD along with briefly outlining the expanding proportion of "copper interactome" in human biology. Using network biology, we found that copper metabolism proteins, superoxide dismutase 1 and ceruloplasmin may represent direct and indirect link with AD and PD, respectively.

  17. Acute toxicity, accumulation and tissue distribution of copper in the blue crab Callinectes sapidus acclimated to different salinities: In vivo and in vitro studies

    Energy Technology Data Exchange (ETDEWEB)

    De Martinez Gaspar Martins, Camila [Programa de Pos-Graduacao em Ciencias Fisiologicas - Fisiologia Animal Comparada, Instituto de Ciencias Biologicas, Universidade Federal do Rio Grande (FURG), Campus Carreiros, Av. Italia km 8, 96201-900, Rio Grande, RS (Brazil); Barcarolli, Indianara Fernanda; Menezes, Eliana Jaime de; Mussoi Giacomin, Marina [Instituto de Ciencias Biologicas, Universidade Federal do Rio Grande (FURG), Campus Carreiros, Av. Italia km 8, 96201-900, Rio Grande, RS (Brazil); Wood, Chris M. [McMaster University, Department of Biology, 1280 Main Street West, Hamilton, ON, L8S 4K1 (Canada); Bianchini, Adalto, E-mail: adaltobianchini@furg.br [Programa de Pos-Graduacao em Ciencias Fisiologicas - Fisiologia Animal Comparada, Instituto de Ciencias Biologicas, Universidade Federal do Rio Grande (FURG), Campus Carreiros, Av. Italia km 8, 96201-900, Rio Grande, RS (Brazil); Instituto de Ciencias Biologicas, Universidade Federal do Rio Grande (FURG), Campus Carreiros, Av. Italia km 8, 96201-900, Rio Grande, RS (Brazil)

    2011-01-17

    In vivo and in vitro studies were performed to evaluate acute toxicity, organ-specific distribution, and tissue accumulation of copper in Callinectes sapidus acclimated to two different experimental salinities (2 and 30 ppt). Blue crabs were quite tolerant to copper. Acute dissolved copper toxicity (96-h LC{sub 50} and its corresponding 95% confident interval) was higher at salinity 2 ppt (5.3 (3.50-8.05) {mu}M Cu) than at 30 ppt (53.0 (27.39-102.52) {mu}M Cu). The difference between salinities can be completely explained based on the water chemistry because it disappeared when 96-h LC{sub 50} values were expressed as the free Cu{sup 2+} ion (3.1 (1.93-4.95) {mu}M free Cu at 2 ppt versus 5.6 (2.33-13.37) {mu}M free Cu at 30 ppt) or the Cu{sup 2+} activity (1.4 (0.88-2.26) {mu}M Cu activity at 2 ppt versus 1.7 (0.71-4.07) {mu}M Cu activity at 30 ppt). The relationships between gill Cu burden and % mortality were very similar at 2 and 30 ppt, in accord with the Biotic Ligand Model. In vivo experiments showed that copper concentration in the hemolymph is not dependent on metal concentration in the surrounding medium at either experimental salinity. They also showed that copper flux into the gills is higher than into other tissues analyzed, and that anterior and posterior gills are similarly important sites of copper accumulation at both experimental salinities. In vitro experiments with isolated-perfused gills showed that there is a positive relationship between copper accumulation in this tissue and the metal concentration in the incubation media for both anterior and posterior gills. A similar result was observed at both low and high salinities. Furthermore, in vitro experiments showed that copper accumulation in posterior gills is also positively and strongly dependent on the incubation time with copper. Gill copper accumulation occurred at a lower rate in the first 2 h of metal exposure, increasing markedly after this 'steady-state' period. This finding

  18. A Blue Native-PAGE analysis of membrane protein complexes in Clostridium thermocellum

    Directory of Open Access Journals (Sweden)

    Fan Keqiang

    2011-01-01

    Full Text Available Abstract Background Clostridium thermocellum is a Gram-positive thermophilic anaerobic bacterium with the unusual capacity to convert cellulosic biomass into ethanol and hydrogen. Identification and characterization of protein complexes in C. thermocellum are important toward understanding its metabolism and physiology. Results A two dimensional blue native/SDS-PAGE procedure was developed to separate membrane protein complexes of C. thermocellum. Proteins spots were identified by MALDI-TOF/TOF Mass spectrometry. 24 proteins were identified representing 13 distinct protein complexes, including several putative intact complexes. Interestingly, subunits of both the F1-F0-ATP synthase and the V1-V0-ATP synthase were detected in the membrane sample, indicating C. thermocellum may use alternative mechanisms for ATP generation. Conclusion Two dimensional blue native/SDS-PAGE was used to detect membrane protein complexes in C. thermocellum. More than a dozen putative protein complexes were identified, revealing the simultaneous expression of two sets of ATP synthase. The protocol developed in this work paves the way for further functional characterization of these protein complexes.

  19. Non-decoloured In-gel Digestion of Coomassie Blue-stained Proteins

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guo-an; BAO Hui-min; FAN Hui-zhi; YANG Peng-yuan

    2003-01-01

    A simplified method is presented for tryptic digestion of Coomassie brilliant blue(CBB)-stained proteins in polyacrylamide gels. Compared with conventional methods, the proposed method does not require a removal of the dye before digestion, and is thus faster and saves a lot of labor. The resulted digest can be analyzed by either RPLC/ESIMS or MALDI MS for identification of the protein in a conventional way. Model studies with bovine serum albumin(BSA) showed that 50 ng of the protein could be routinely identified. The simplified procedure displays a tendency to produce more incompletely cleaved peptides, which is favorable for improving the sequence coverage.

  20. Association of bilirubin and protein thiols in relation to copper and ceruloplasmin in hyperbilirubinemic patients

    Institute of Scientific and Technical Information of China (English)

    Mungli Prakash; Jeevan K Shetty; Roshan D'Souza; Suhasa Upadhya; Vijay Kumar

    2009-01-01

    Objective:Bilirubin is a double edged sword in biological system,acting as a toxic molecule and cytoprotecrant.Unconjugated bilirubin is proved to show antioxidant activity in vitro and in vivo.In the current work we tried to know the relationship between both conjugated and unconjugated bilirubin with copper and protein thiols in patients with hyperbilirnbinemia.Methods:Study was conducted on 56 hyperbilirubinemic cases and 56 healthy controls.Serum copper,ceruloplasmin,protein thiols,total bilirubin,conjugated and unconjugated bilirubin,unconjugated bilimbin/albumin ratio,total protein,albumin,AST,ALT and ALP were estimated.Results:There was significant increase in serum copper,total bilirubin,conjugated and unconjugated bilimbin.uriconjugated bilirubin/albumin ratio,AST,ALT,and ALP,and decrease in serum ceruloplasmin,protein thiols,total protein,and albumin in hyperbilimbinemic cases when compared to healthy controls.Conjugated bilimbin correlated positively with liver enzymes AST and ALP,and negatively with protein thials,total protein and albumin.Unconjugated bilirubin correlated positively with ALT.Protein thiols correlated negatively with copper and positively with ceruloplasmin,and also correlated negativelv with liver enzymes like AST,ALT and ALP,and positively with total protein and albumin.Conclusion:Combination of elevated levels of trace elements like copper and availability of reducing agent like bilimbin may prove deleterious by generating free radicals.

  1. The E1 copper binding domain of full-length amyloid precursor protein mitigates copper-induced growth inhibition in brain metastatic prostate cancer DU145 cells

    Energy Technology Data Exchange (ETDEWEB)

    Gough, Mallory, E-mail: m.gough1@lancaster.ac.uk; Blanthorn-Hazell, Sophee, E-mail: s.blanthorn-hazell@lancaster.ac.uk; Delury, Craig, E-mail: c.delury@lancaster.ac.uk; Parkin, Edward, E-mail: e.parkin@lancaster.ac.uk

    2014-10-31

    Highlights: • Copper levels are elevated in the tumour microenvironment. • APP mitigates copper-induced growth inhibition of DU145 prostate cancer (PCa) cells. • The APP intracellular domain is a prerequisite; soluble forms have no effect. • The E1 CuBD of APP is also a prerequisite. • APP copper binding potentially mitigates copper-induced PCa cell growth inhibition. - Abstract: Copper plays an important role in the aetiology and growth of tumours and levels of the metal are increased in the serum and tumour tissue of patients affected by a range of cancers including prostate cancer (PCa). The molecular mechanisms that enable cancer cells to proliferate in the presence of elevated copper levels are, therefore, of key importance in our understanding of tumour growth progression. In the current study, we have examined the role played by the amyloid precursor protein (APP) in mitigating copper-induced growth inhibition of the PCa cell line, DU145. A range of APP molecular constructs were stably over-expressed in DU145 cells and their effects on cell proliferation in the presence of copper were monitored. Our results show that endogenous APP expression was induced by sub-toxic copper concentrations in DU145 cells and over-expression of the wild-type protein was able to mitigate copper-induced growth inhibition via a mechanism involving the cytosolic and E1 copper binding domains of the full-length protein. APP likely represents one of a range of copper binding proteins that PCa cells employ in order to ensure efficient proliferation despite elevated concentrations of the metal within the tumour microenvironment. Targeting the expression of such proteins may contribute to therapeutic strategies for the treatment of cancers.

  2. Structural Studies of the Alzheimer's Amyloid Precursor Protein Copper-Binding Domain Reveal How It Binds Copper Ions

    Energy Technology Data Exchange (ETDEWEB)

    Kong, G.K.-W.; Adams, J.J.; Harris, H.H.; Boas, J.F.; Curtain, C.C.; Galatis, D.; Master, C.L.; Barnham, K.J.; McKinstry, W.J.; Cappai, R.; Parker, M.W.; /Sydney U.

    2007-07-09

    Alzheimer's disease (AD) is the major cause of dementia. Amyloid {beta} peptide (A {beta}), generated by proteolytic cleavage of the amyloid precursor protein (APP), is central to AD pathogenesis. APP can function as a metalloprotein and modulate copper (Cu) transport, presumably via its extracellular Cu-binding domain (CuBD). Cu binding to the CuBD reduces A{beta} levels, suggesting that a Cu mimetic may have therapeutic potential. We describe here the atomic structures of apo CuBD from three crystal forms and found they have identical Cu-binding sites despite the different crystal lattices. The structure of Cu[2+]-bound CuBD reveals that the metal ligands are His147, His151, Tyrl68 and two water molecules, which are arranged in a square pyramidal geometry. The site resembles a Type 2 non-blue Cu center and is supported by electron paramagnetic resonance and extended X-ray absorption fine structure studies. A previous study suggested that Met170 might be a ligand but we suggest that this residue plays a critical role as an electron donor in CuBDs ability to reduce Cu ions. The structure of Cu[+]-bound CuBD is almost identical to the Cu[2+]-bound structure except for the loss of one of the water ligands. The geometry of the site is unfavorable for Cu[+], thus providing a mechanism by which CuBD could readily transfer Cu ions to other proteins.

  3. IN ABSENCE OF THE CELLULAR PRION PROTEIN, ALTERATIONS IN COPPER METABOLISM AND COPPER-DEPENDENT OXIDASE ACTIVITY AFFECT IRON DISTRIBUTION

    OpenAIRE

    Lisa Gasperini; Elisa Meneghetti; Giuseppe Legname; Federico Benetti

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defin...

  4. In Absence of the Cellular Prion Protein, Alterations in Copper Metabolism and Copper-Dependent Oxidase Activity Affect Iron Distribution

    OpenAIRE

    Gasperini, Lisa; Meneghetti, Elisa; Legname, Giuseppe; Benetti, Federico

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defin...

  5. The E1 copper binding domain of full-length amyloid precursor protein mitigates copper-induced growth inhibition in brain metastatic prostate cancer DU145 cells.

    Science.gov (United States)

    Gough, Mallory; Blanthorn-Hazell, Sophee; Delury, Craig; Parkin, Edward

    2014-10-31

    Copper plays an important role in the aetiology and growth of tumours and levels of the metal are increased in the serum and tumour tissue of patients affected by a range of cancers including prostate cancer (PCa). The molecular mechanisms that enable cancer cells to proliferate in the presence of elevated copper levels are, therefore, of key importance in our understanding of tumour growth progression. In the current study, we have examined the role played by the amyloid precursor protein (APP) in mitigating copper-induced growth inhibition of the PCa cell line, DU145. A range of APP molecular constructs were stably over-expressed in DU145 cells and their effects on cell proliferation in the presence of copper were monitored. Our results show that endogenous APP expression was induced by sub-toxic copper concentrations in DU145 cells and over-expression of the wild-type protein was able to mitigate copper-induced growth inhibition via a mechanism involving the cytosolic and E1 copper binding domains of the full-length protein. APP likely represents one of a range of copper binding proteins that PCa cells employ in order to ensure efficient proliferation despite elevated concentrations of the metal within the tumour microenvironment. Targeting the expression of such proteins may contribute to therapeutic strategies for the treatment of cancers.

  6. Copper reduces striatal protein nitration and tyrosine hydroxylase inactivation induced by MPP+ in rats.

    Science.gov (United States)

    Rubio-Osornio, M; Montes, S; Pérez-Severiano, F; Aguilera, P; Floriano-Sánchez, E; Monroy-Noyola, A; Rubio, C; Ríos, C

    2009-06-01

    Striatal administration of 1-methyl-4-phenylpyridinium (MPP(+)), the active metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), causes nigrostriatal dopaminergic pathway damage similar to that observed in Parkinson's disease. Copper acts as a prosthetic group of several antioxidant enzymes and recent data show that copper attenuated MPP(+)-evoked neurotoxicity. We evaluated the effect of copper (as a supplement) upon proteins nitration (60 kDa) and tyrosine hydroxylase (TH) inactivation induced by MPP(+) (10 microg/8 microL) injection into the rat striatum. Copper pretreatment (10 micromol/kg i.p.) prevented both MPP(+)-induced proteins nitration and TH inactivation. Copper treatment also prevented the dopamine-depleting effect of MPP(+) injection. Those results were accompanied by a significant reduction of enzymatic activity of the constitutive nitric oxide synthase (cNOS), whereas, the protein levels of the three isoforms of NOS remained unchanged. Results indicate that the effect of copper against MPP(+)-induced proteins nitration and TH inactivation in the striatum of rat may be mediated by a reduction of cNOS activity.

  7. DCCP and DICP: Construction and Analyses of Databases for Copper- and Iron-Chelating Proteins

    Institute of Scientific and Technical Information of China (English)

    Hao Wu; Yan Yang; Sheng-Juan Jiang; Ling-Ling Chen; Hai-Xia Gao; Qing-Shan Fu; Feng Li; Bin-Guang Ma; Hong-Yu Zhang

    2005-01-01

    Copper and iron play important roles in a variety of biological processes, especially when being chelated with proteins. The proteins involved in the metal binding,transporting and metabolism have aroused much interest. To facilitate the study on this topic, we constructed two databases (DCCP and DICP) containing the known copper- and iron-chelating proteins, which are freely available from the website http:∥sdbi.sdut.edu.cn/en. Users can conveniently search and browse all of the entries in the databases. Based on the two databases, bioinformatic analyses were performed, which provided some novel insights into metalloproteins.

  8. Functional understanding of the versatile protein copper metabolism MURR1 domain 1 (COMMD1) in copper homeostasis

    NARCIS (Netherlands)

    Fedoseienko, Alina; Bartuzi, Paulina; van de Sluis, Bart

    2014-01-01

    Copper is an important cofactor in numerous biological processes in all living organisms. However, excessive copper can be extremely toxic, so it is vital that the copper level within a cell is tightly regulated. The damaging effect of copper is seen in several hereditary forms of copper toxicity in

  9. Investigation of the effects of dietary protein source on copper and zinc bioavailability in rainbow trout

    Science.gov (United States)

    Limited research has examined the effects that dietary protein sources have on copper (Cu) and Zinc (Zn) absorption, interactions and utilization in rainbow trout. Therefore, the objective of the first trial was to determine what effect protein source (plant vs. animal based), Cu source (complex vs....

  10. Non-hepatic tumors change the activity of genes encoding copper trafficking proteins in the liver.

    Science.gov (United States)

    Babich, Polina S; Skvortsov, Alexey N; Rusconi, Paolo; Tsymbalenko, Nadezhda V; Mutanen, Marja; Puchkova, Ludmila V; Broggini, Massimo

    2013-07-01

    To assess the statistical relationship between tumor growth and copper metabolism, we performed a metaanalysis of studies in which patients with neoplasms were characterized according to any of the copper status indexes (atomic copper serum concentration, serum oxidase activity, ceruloplasmin protein content). Our metaanalysis shows that in the majority of cases (more than 3100 patients), tumor growth positively correlates with the copper status indexes. Nude athymic CD-1 nu/nu mice with subcutaneous tumors of human origin, C57Bl/6J mice with murine melanoma and Apc(Min) mice with spontaneously developing adenomas throughout the intestinal tract were studied to experimentally determine the relationship between tumor progression, liver copper metabolism, and copper status indexes. We showed that the copper status indexes increased significantly during tumor growth. In the liver tissue of tumor-bearing mice, ceruloplasmin gene expression, as well as the expression of genes related to ceruloplasmin metallation (CTR1 and ATP7B), increased significantly. Moreover, the presence of an mRNA splice variant encoding a form of ceruloplasmin anchored to the plasma membrane by glycosylphosphatidyl inositol, which is atypical for hepatocytes, was also detected. The ATP7A copper transporter gene, which is normally expressed in the liver only during embryonic copper metabolism, was also activated. Depletion of holo-ceruloplasmin resulted in retardation of human HCT116 colon carcinoma cell growth in nude mice and induced DNA fragmentation in tumor cells. In addition, the concentration of cytochrome c increased significantly in the cytosol, while decreasing in the mitochondria. We discuss a possible trans-effect of developing tumors on copper metabolism in the liver.

  11. Affinity purification of copper-chelating peptides from sunflower protein hydrolysates.

    Science.gov (United States)

    Megías, Cristina; Pedroche, Justo; Yust, Maria M; Girón-Calle, Julio; Alaiz, Manuel; Millan, Francisco; Vioque, Javier

    2007-08-08

    Copper-chelating peptides were purified from sunflower protein hydrolysates by affinity chromatography using immobilized copper. A variety of protein hydrolysates were obtained by incubation with the proteases Alcalase and Flavourzyme for different periods of time. Chelating activity was indirectly determined by measuring the inhibitory effect of hydrolysates on the oxidation of beta-carotene by copper. Copper-binding peptides purified from the two hydrolysates that inhibited oxidation by copper the most contained 25.4 and 42.0% histidine and inhibited beta-carotene oxidation 8 and 3 times more than the original hydrolysates, which had 2.4 and 2.6% histidine, respectively. Thus, histidine content is not the only factor involved in antioxidant activity, and probably other factors such as peptide size and amino acid sequence are also important. This work shows that affinity chromatography can be used for the purification of copper-chelating peptides and probably other metals of nutritional interest such as calcium, iron, and zinc. In addition to their antioxidant potential, chelating peptides are of nutritional interest because they increase bioavailability of minerals.

  12. Analysis of Copper-binding Proteins in Rice Radicles Exposed to Excess Copper and Hydrogen Peroxide Stress

    Directory of Open Access Journals (Sweden)

    Hongxiao Zhang

    2016-08-01

    Full Text Available Copper (Cu is an essential micronutrient for plants, but excess Cu can inactivate and disturb the protein function due to unavoidable binding to proteins at the cellular level. As a redox-active metal, Cu toxicity is mediated by the formation of reactive oxygen species (ROS. Cu-binding structural motifs may alleviate Cu-induced damage by decreasing free Cu2+ activity in cytoplasm or scavenging ROS. The identification of Cu-binding proteins involved in the response of plants to Cu or ROS toxicity may increase our understanding the mechanisms of metal toxicity and tolerance in plants. This study investigated change of Cu-binding proteins in radicles of germinating rice seeds under excess Cu and oxidative stress using immobilized Cu2+ affinity chromatography, two-dimensional electrophoresis, and mass spectra analysis. Quantitative image analysis revealed that 26 protein spots showed more than a 1.5-fold difference in abundances under Cu or H2O2 treatment compared to the control. The identified Cu-binding proteins were involved in anti-oxidative defense, stress response and detoxification, protein synthesis, protein modification, and metabolism regulation. The present results revealed that 17 out of 24 identified Cu-binding proteins have a similar response to low concentration Cu and H2O2 stress, and 5 out of 24 were increased under low and high concentration Cu but unaffected under H2O2 stress, which hint Cu ions can regulate Cu-binding proteins accumulation by H2O2 or no H2O2 pathway to cope with excess Cu in cell. The change pattern of these Cu-binding proteins and their function analysis warrant to further study the roles of Cu ions in these Cu-binding proteins of plant cells.

  13. Comparing potential copper chelation mechanisms in Parkinson's disease protein

    Science.gov (United States)

    Rose, Frisco; Hodak, Miroslav; Bernholc, Jerry

    2011-03-01

    We have implemented the nudged elastic band (NEB) as a guided dynamics framework for our real-space multigrid method of DFT-based quantum simulations. This highly parallel approach resolves a minimum energy pathway (MEP) on the energy hypersurface by relaxing intermediates in a chain-of-states. As an initial application we present an investigation of chelating agents acting on copper ion bound to α -synuclein, whose misfolding is implicated in Parkinson's disease (PD). Copper ions are known to act as highly effective misfolding agents in a-synuclein and are thus an important target in understanding PD. Furthermore, chelation therapy has shown promise in the treatment of Alzheimer's and other neuro-degenerative diseases with similar metal-correlated pathologies. At present, our candidate chelating agents include nicotine, curcumin and clioquinol. We examine their MEP activation barriers in the context of a PD onset mechanism to assess the viability of various chelators for PD remediation.

  14. Electrochemical Study on the Interaction of Protein with Bromothymol Blue and Its Analytical Application

    Institute of Scientific and Technical Information of China (English)

    WANG Xue-liang; YANG Jie; JIAO Kui

    2008-01-01

    The interaction ofbromothymol blue(BB) with human serum albumin(HSA) was studied by electrochemical techniques and a sensitive method for proteins assay was developed.When BB interacted with HSA,the voltammetric peak current value of BB decreased linearly with the concentration of HSA in a range of 1.0-40.0 mg/L,and the peak potential shifted negatively.Based on the results,a sensitive assay method for proteins,such as HSA,bovine serum albumin(BSA),and egg albumin etc.was established.This method was further applied to determining the HSA in healthy human blood samples,and the results are not significantly different from those obtained by the classic Coomassie Brilliant Blue G-250 spectrophotometic method.The detecting conditions of this method were optimized and the interaction mechanism was discussed.The results show that the electrochemical parameters(formal potential E0,standard rate constant of the electrode reaction ks,parameter of kinetic na) of BB have no obvious changes before and after the interaction,which indicate that BB can interact with HSA,forming an electrochemical non-active complex.The equilibrium constant(βs) and the binding ratio(m) for this complex were calculated.The m is 4 and β,is 1.41 × 1019.This method is fast,simple,highly sensitive,and has good selectivity,which can be used in clinical measurements.

  15. Bacterial cytosolic proteins with a high capacity for Cu(I) that protect against copper toxicity

    Science.gov (United States)

    Vita, Nicolas; Landolfi, Gianpiero; Baslé, Arnaud; Platsaki, Semeli; Lee, Jaeick; Waldron, Kevin J.; Dennison, Christopher

    2016-12-01

    Bacteria are thought to avoid using the essential metal ion copper in their cytosol due to its toxicity. Herein we characterize Csp3, the cytosolic member of a new family of bacterial copper storage proteins from Methylosinus trichosporium OB3b and Bacillus subtilis. These tetrameric proteins possess a large number of Cys residues that point into the cores of their four-helix bundle monomers. The Csp3 tetramers can bind a maximum of approximately 80 Cu(I) ions, mainly via thiolate groups, with average affinities in the (1–2) × 1017 M‑1 range. Cu(I) removal from these Csp3s by higher affinity potential physiological partners and small-molecule ligands is very slow, which is unexpected for a metal-storage protein. In vivo data demonstrate that Csp3s prevent toxicity caused by the presence of excess copper. Furthermore, bacteria expressing Csp3 accumulate copper and are able to safely maintain large quantities of this metal ion in their cytosol. This suggests a requirement for storing copper in this compartment of Csp3-producing bacteria.

  16. Functional understanding of the versatile protein copper metabolism MURR1 domain 1 (COMMD1) in copper homeostasis.

    Science.gov (United States)

    Fedoseienko, Alina; Bartuzi, Paulina; van de Sluis, Bart

    2014-05-01

    Copper is an important cofactor in numerous biological processes in all living organisms. However, excessive copper can be extremely toxic, so it is vital that the copper level within a cell is tightly regulated. The damaging effect of copper is seen in several hereditary forms of copper toxicity in humans and animals. At present, Wilson's disease is the best-described and best-studied copper-storage disorder in humans; it is caused by mutations in the ATP7B gene. In dogs, a mutation in the COMMD1 gene has been found to be associated with copper toxicosis. Using a liver-specific Commd1 knockout mouse, the biological role of Commd1 in copper homeostasis has been confirmed. Yet, the exact mechanism by which COMMD1 regulates copper homeostasis is still unknown. Here, we give an overview of the current knowledge and perspectives on the molecular function of COMMD1 in copper homeostasis.

  17. Methylene blue induces macroautophagy through 5' adenosine monophosphate-activated protein kinase pathway to protect neurons from serum deprivation.

    Science.gov (United States)

    Xie, Luokun; Li, Wenjun; Winters, Ali; Yuan, Fang; Jin, Kunlin; Yang, Shaohua

    2013-01-01

    Methylene blue has been shown to be neuroprotective in multiple experimental neurodegenerative disease models. However, the mechanisms underlying the neuroprotective effects have not been fully elucidated. Previous studies have shown that macroautophagy has multiple beneficial roles for maintaining normal cellular homeostasis and that induction of macroautophagy after myocardial ischemia is protective. In the present study we demonstrated that methylene blue could protect HT22 hippocampal cell death induced by serum deprivation, companied by induction of macroautophagy. We also found that methylene blue-mediated neuroprotection was abolished by macroautophagy inhibition. Interestingly, 5' adenosine monophosphate-activated protein kinase (AMPK) signaling, but not inhibition of mammalian target of rapamycin signaling, was activated at 12 and 24 h after methylene blue treatment in a dose-dependent manner. Methylene blue-induced macroautophagy was blocked by AMPK inhibitor. Consistent with in vitro data, macroautophagy was induced in the cortex and hippocampus of mouse brains treated with methylene blue. Our findings suggest that methylene blue-induced neuroprotection is mediated, at least in part, by macroautophagy though activation of AMPK signaling.

  18. Relative and combined effects of ethanol and protein deficiency on bone manganese and copper.

    Science.gov (United States)

    González-Pérez, José M; González-Reimers, Emilio; DeLaVega-Prieto, María José; Durán-Castellón, María del Carmen; Viña-Rodríguez, José; Galindo-Martín, Luis; Alvisa-Negrín, Julio; Santolaria-Fernández, Francisco

    2012-06-01

    Both manganese and copper may affect bone synthesis. Bone content of both metals can be altered in alcoholics, although controversy exists regarding this matter. To analyse the relative and combined effects of ethanol and a low protein diet on bone copper and manganese, and their relationships with bone structure and metabolism, including trabecular bone mass (TBM), osteoid area (OA), osteocalcin (OCN), insulin-like growth factor-1 (IGF-1), parathyroid hormone (PTH), urinary hydroxyproline (uHP) and vitamin D. Adult male Sprague-Dawley rats were divided into four groups. The control rats received a 18% protein-containing diet; a second group, an isocaloric, 2% protein-containing diet; a third one, an isocaloric, 36% ethanol-containing diet and a fourth, an isocaloric diet containing 2% protein and 36% ethanol. After sacrifice, TBM and OA were histomorphometrically assessed; bone and serum manganese and copper were determined by atomic absorption spectrophotometry, and serum OCN, IGF-1, PTH, uHP and vitamin D by radioimmunoassay. Ethanol-fed rats showed decreased TBM and bone manganese. Significant relationships existed between bone manganese and TBM, serum IGF-1 and OCN. Ethanol leads to a decrease in bone manganese, related to decreased bone mass and bone synthesis. No alterations were found in bone copper.

  19. A plant-specific protein essential for blue-light-induced chloroplast movements.

    Science.gov (United States)

    DeBlasio, Stacy L; Luesse, Darron L; Hangarter, Roger P

    2005-09-01

    In Arabidopsis (Arabidopsis thaliana), light-dependent chloroplast movements are induced by blue light. When exposed to low fluence rates of light, chloroplasts accumulate in periclinal layers perpendicular to the direction of light, presumably to optimize light absorption by exposing more chloroplast area to the light. Under high light conditions, chloroplasts become positioned parallel to the incoming light in a response that can reduce exposure to light intensities that may damage the photosynthetic machinery. To identify components of the pathway downstream of the photoreceptors that mediate chloroplast movements (i.e. phototropins), we conducted a mutant screen that has led to the isolation of several Arabidopsis mutants displaying altered chloroplast movements. The plastid movement impaired1 (pmi1) mutant exhibits severely attenuated chloroplast movements under all tested fluence rates of light, suggesting that it is a necessary component for both the low- and high-light-dependant chloroplast movement responses. Analysis of pmi1 leaf cross sections revealed that regardless of the light condition, chloroplasts are more evenly distributed in leaf mesophyll cells than in the wild type. The pmi1-1 mutant was found to contain a single nonsense mutation within the open reading frame of At1g42550. This gene encodes a plant-specific protein of unknown function that appears to be conserved among angiosperms. Sequence analysis of the protein suggests that it may be involved in calcium-mediated signal transduction, possibly through protein-protein interactions.

  20. Copper(II) binding to alpha-synuclein, the Parkinson's protein.

    Science.gov (United States)

    Lee, Jennifer C; Gray, Harry B; Winkler, Jay R

    2008-06-04

    Variations in tryptophan fluorescence intensities confirm that copper(II) interacts with alpha-synuclein, a protein implicated in Parkinson's disease. Trp4 fluorescence decay kinetics measured for the F4W protein show that Cu(II) binds tightly (Kd 100 nM) near the N-terminus at pH 7. Work on a F4W/H50S mutant indicates that a histidine imidazole is not a ligand in this high-affinity site.

  1. Blue-Light-Independent Activity of Arabidopsis Cryptochromes in the Regulation of Steady-State Levels of Protein and mRNA Expression

    Institute of Scientific and Technical Information of China (English)

    Yue-Jun Yang; Xuan-Ming Liu; Chen-Tao Lin; Ze-Cheng Zuo; Xiao-Ying Zhao; Xu Li; John Klejnot; Yan Li; Ping Chen; Song-Ping Liang; Xu-Hong Yu

    2008-01-01

    Cryptochromes are blue-light receptors that mediate blue-light inhibition of hypocotyl elongation and bluelight stimulation of floral initiation in Arabidopsis. In addition to their blue-light-dependent functions, cryptochromes are also involved in blue-light-independent regulation of the circadian clock, cotyledon unfolding, and hypocotyl inhibition.However, the molecular mechanism associated with the blue-light-independent function of cryptochromes remains unclear. We reported here a comparative proteomics study of the light regulation of protein expression. We showed that, as expected, the protein expression of many metabolic enzymes changed in response to both blue light and red light. Surprisingly, some light-regulated protein expression changes are impaired in the cry1cry2 mutant in both blue light and red light. This result suggests that, in addition to mediating blue-light-dependent regulation of protein expression, cryptochromes are also involved in the blue-light-independent regulation of gene expression. Consistent with this hypothesis,the cry1cry2 mutant exhibited reduced changes of mRNA expression in response to not only blue light, but also red light,although the cryptochrome effects on the red-light-dependent gene expression changes are generally less pronounced.These results support a hypothesis that, in addition to their blue-light-specific functions, cryptochromes also play roles in the control of gene expression mediated by the red/far-red-light receptor phytochromes.

  2. Comparative time-courses of copper-ion-mediated protein and lipid oxidation in low-density lipoprotein

    DEFF Research Database (Denmark)

    Knott, Heather M; Baoutina, Anna; Davies, Michael Jonathan;

    2002-01-01

    Free radicals damage both lipids and proteins and evidence has accumulated for the presence of both oxidised lipids and proteins in aged tissue samples as well as those from a variety of pathologies including atherosclerosis, diabetes, and Parkinson's disease. Oxidation of the protein and lipid......-courses of lipid and protein oxidation during copper-ion-mediated oxidation of low-density lipoprotein. We show that there is an early, lipid-mediated loss of 40-50% of the Trp residues of the apoB100 protein. There is no comparable loss over an identical period during the copper-ion-mediated oxidation of lipid......-free BSA. Concomitant with Trp loss, the antioxidant alpha-tocopherol is consumed with subsequent extensive lipid peroxidation. Further changes to the protein, including the copper-ion-dependent 3.5-fold increase in 3,4-dihydroxyphenylalanine and the copper-ion-independent 3-5-fold increase in o...

  3. Overexpression of amyloid precursor protein increases copper content in HEK293 cells

    Energy Technology Data Exchange (ETDEWEB)

    Suazo, Miriam; Hodar, Christian; Morgan, Carlos [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile); Cerpa, Waldo [Centro de Envejecimiento y Regeneracion (CARE), Centro de Regulacion Celular y Patologia ' Joaquin V. Luco' (CRCP), MIFAB, Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago (Chile); Cambiazo, Veronica [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile); Millenium Nucleus CGC, Universidad de Chile (Chile); Inestrosa, Nibaldo C. [Centro de Envejecimiento y Regeneracion (CARE), Centro de Regulacion Celular y Patologia ' Joaquin V. Luco' (CRCP), MIFAB, Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago (Chile); Gonzalez, Mauricio, E-mail: mgonzale@inta.cl [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile)

    2009-05-15

    Amyloid precursor protein (APP) is a transmembrane glycoprotein widely expressed in mammalian tissues and plays a central role in Alzheimer's disease. However, its physiological function remains elusive. Cu{sup 2+} binding and reduction activities have been described in the extracellular APP135-156 region, which might be relevant for cellular copper uptake and homeostasis. Here, we assessed Cu{sup 2+} reduction and {sup 64}Cu uptake in two human HEK293 cell lines overexpressing APP. Our results indicate that Cu{sup 2+} reduction increased and cells accumulated larger levels of copper, maintaining cell viability at supra-physiological levels of Cu{sup 2+} ions. Moreover, wild-type cells exposed to both Cu{sup 2+} ions and APP135-155 synthetic peptides increased copper reduction and uptake. Complementation of function studies in human APP751 transformed Fre1 defective Saccharomyces cerevisiae cells rescued low Cu{sup 2+} reductase activity and increased {sup 64}Cu uptake. We conclude that Cu{sup 2+} reduction activity of APP facilitates copper uptake and may represent an early step in cellular copper homeostasis.

  4. Comparison of antioxidative and chelating effects of daidzein and daidzin on protein oxidative modification by copper in vitro.

    Science.gov (United States)

    Toda, S; Shirataki, Y

    2001-01-01

    Daidzein and its glycoside daidzin are isoflavones. Their antioxidative effects were compared in vitro. Although both compounds inhibited protein oxidative modification by copper, the inhibitory effect of daidzein was stronger than that of daidzin. Because daidzein showed a greater affinity for Cu2+, the antioxidant effect of these isoflavones may be dependent on their respective copper-chelating abilities.

  5. Hepatocyte-specific localization and copper-dependent trafficking of the Wilson's disease protein in the liver.

    Science.gov (United States)

    Schaefer, M; Hopkins, R G; Failla, M L; Gitlin, J D

    1999-03-01

    Wilson's disease is an inherited disorder of copper metabolism characterized by hepatic cirrhosis and neuronal degeneration. In this current study, a polyclonal antiserum specific for the Wilson's disease ATPase was used to examine the hepatic expression of this protein. Immunoblot analysis of lysates from human and rat liver detected a single 165-kDa protein, which by immunofluorescence was present only in hepatocytes and localized predominantly to the trans-Golgi network and exclusively in this compartment under low hepatic copper concentrations. Although hepatic copper concentration had no effect on the steady-state levels of the Wilson's disease protein, copper administration in vivo resulted in redistribution of this protein to a cytoplasmic vesicular compartment localized toward the hepatocyte canalicular membrane. The relative abundance of the Wilson's disease protein in the liver was found to be greatest in the fetus before the onset of biliary copper excretion. Taken together, these studies reveal a novel posttranslational mechanism of copper homeostasis in vivo consistent with the proposed function of the Wilson's disease protein in holoceruloplasmin biosynthesis and biliary copper excretion and of relevance to the broad clinical heterogeneity observed in this disease.

  6. Crystal structure of Korean pine (Pinus koraiensis) 7S seed storage protein with copper ligands.

    Science.gov (United States)

    Jin, Tengchuan; Wang, Yang; Chen, Yu-Wei; Fu, Tong-Jen; Kothary, Mahendra H; McHugh, Tara H; Zhang, Yuzhu

    2014-01-08

    The prevalence of food allergy has increased in recent years, and Korean pine vicilin is a potential food allergen. We have previously reported the crystallization of Korean pine vicilin purified from raw pine nut. Here we report the isolation of vicilin mRNA and the crystal structure of Korean pine vicilin at 2.40 Å resolution. The overall structure of pine nut vicilin is similar to the structures of other 7S seed storage proteins and consists of an N-terminal domain and a C-terminal domain. Each assumes a cupin fold, and they are symmetrically related about a pseudodyad axis. Three vicilin molecules form a doughnut-shaped trimer through head-to-tail association. Structure characterization of Korean pine nut vicilin unexpectedly showed that, in its native trimeric state, the vicilin has three copper ligands. Sequence alignments suggested that the copper-coordinating residues were conserved in winter squash, sesame, tomato, and several tree nuts, while they were not conserved in a number of legumes, including peanut and soybean. Additional studies are needed to assess whether the copper-coordinating property of vicilins has a biological function in the relevant plants. The nutritional value of this copper-coordinating protein in tree nuts and other edible seeds may be worth further investigations.

  7. In vitro thermodynamic dissection of human copper transfer from chaperone to target protein.

    Directory of Open Access Journals (Sweden)

    Moritz S Niemiec

    Full Text Available Transient protein-protein and protein-ligand interactions are fundamental components of biological activity. To understand biological activity, not only the structures of the involved proteins are important but also the energetics of the individual steps of a reaction. Here we use in vitro biophysical methods to deduce thermodynamic parameters of copper (Cu transfer from the human copper chaperone Atox1 to the fourth metal-binding domain of the Wilson disease protein (WD4. Atox1 and WD4 have the same fold (ferredoxin-like fold and Cu-binding site (two surface exposed cysteine residues and thus it is not clear what drives metal transfer from one protein to the other. Cu transfer is a two-step reaction involving a metal-dependent ternary complex in which the metal is coordinated by cysteines from both proteins (i.e., Atox1-Cu-WD4. We employ size exclusion chromatography to estimate individual equilibrium constants for the two steps. This information together with calorimetric titration data are used to reveal enthalpic and entropic contributions of each step in the transfer process. Upon combining the equilibrium constants for both steps, a metal exchange factor (from Atox1 to WD4 of 10 is calculated, governed by a negative net enthalpy change of ∼10 kJ/mol. Thus, small variations in interaction energies, not always obvious upon comparing protein structures alone, may fuel vectorial metal transfer.

  8. Covalent protein-oligonucleotide conjugates by copper-free click reaction.

    Science.gov (United States)

    Khatwani, Santoshkumar L; Kang, Jun Sung; Mullen, Daniel G; Hast, Michael A; Beese, Lorena S; Distefano, Mark D; Taton, T Andrew

    2012-07-15

    Covalent protein-oligodeoxynucleotide (protein-ODN) conjugates are useful in a number of biological applications, but synthesizing discrete conjugates-where the connection between the two components is at a defined location in both the protein and the ODN-under mild conditions with significant yield can be a challenge. In this article, we demonstrate a strategy for synthesizing discrete protein-ODN conjugates using strain-promoted azide-alkyne [3+2] cycloaddition (SPAAC, a copper-free 'click' reaction). Azide-functionalized proteins, prepared by enzymatic prenylation of C-terminal CVIA tags with synthetic azidoprenyl diphosphates, were 'clicked' to ODNs that had been modified with a strained dibenzocyclooctyne (DIBO-ODN). The resulting protein-ODN conjugates were purified and characterized by size-exclusion chromatography and gel electrophoresis. We find that the yields and reaction times of the SPAAC bioconjugation reactions are comparable to those previously reported for copper-catalyzed azide-alkyne [3+2] cycloaddition (CuAAC) bioconjugation, but require no catalyst. The same SPAAC chemistry was used to immobilize azide-modified proteins onto surfaces, using surface-bound DIBO-ODN as a heterobifunctional linker. Cu-free click bioconjugation of proteins to ODNs is a simple and versatile alternative to Cu-catalyzed click methods.

  9. Effects of copper on chlorophyll, proline, protein and abscisic acid level of sunflower (Helianthus annuus L.) seedlings.

    Science.gov (United States)

    Zengin, Fikriye Kirbag; Kirbag, Sevda

    2007-07-01

    The effect of copperchloride (CuCl2) on the level of chlorophyll (a+b), proline, protein and abscisic acid in sunflower (Helianthus annuus L.) seedlings were investigated Control and copper treated (0.4, 0.5 and 0.6 mM) seedlings were grown for ten days in Hoagland solution. Abscisic acid content was determined in root, shoot and leaf tissues of seedlings by HPLC. Copper stress caused significant increase of the abscisic acid contents in roots, shoots and leaves of seedlings. The increase was dependent on the copper salt concentration. Enhanced accumulation of proline in the leaves of seedlings exposed to copper was determined, as well as a decrease of chlorophyll (a+b) and total protein (p Helianthus annuus L.) seedlings. Thus, we assumed that copper levels increase above some critical points seedling growth get negative effects. This assumption is in line with previous findings.

  10. Copper excess impairs mobilization of storage proteins in bean cotyledons.

    Science.gov (United States)

    Karmous, Inès; El Ferjani, Ezzedine; Chaoui, Abdelilah

    2011-12-01

    Germination represents a limiting stage of plant life cycle. One of the underlying metabolic activities following imbibition of seed is the reserve mobilization. Seeds of bean (Phaseolus vulgaris L. var. soisson nain hatif) were germinated by soaking in distilled water or 200 μM CuCl(2). Storage proteins breakdown and amino acids freeing from reserve tissues were investigated. Compared to the control, Cu caused a reduction in germination rate, embryo growth, and in mobilization of cotyledonary biomass. The failure in albumin and globulin hydrolysis after the exposure to the pollutant was argued by (1) higher contents of remaining proteins than control ones, (2) persistence of some polypeptide bands resolved by polyacrylamide gel electrophoresis of albumin and globulin-rich fractions, and (3) decrease in the availability of amino acids. Nitrogen starvation in embryonic axis should be associated with the Cu-imposed delay in growth.

  11. Mass spectrometry data from a quantitative analysis of protein expression in gills of immuno-challenged blue mussels (Mytilus edulis).

    Science.gov (United States)

    Hörnaeus, K; Guillemant, J; Mi, J; Hernroth, B; Bergquist, J; Lind, S Bergström

    2016-09-01

    Here, we provide the dataset associated with our research article on the potential effects of ocean acidification on antimicrobial peptide (AMP) activity in the gills of Mytilus edulis, "Impact of ocean acidification on antimicrobial activity in gills of the blue mussel (Mytilus edulis)" [1]. Blue mussels were stimulated with lipopolysaccharides and samples were collected at different time points post injection. Protein extracts were prepared from the gills, digested using trypsin and a full in-depth proteome investigation was performed using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Protein identification and quantification was performed using the MaxQuant 1.5.1.2 software, "MaxQuant enables high peptide identification rates, individualized p.p.b.-range mass accuracies and proteome-wide protein quantification" [2].

  12. Identification of copper phthalocyanine blue polymorphs in unaged and aged paint systems by means of micro-Raman spectroscopy and Random Forest.

    Science.gov (United States)

    Anghelone, Marta; Jembrih-Simbürger, Dubravka; Schreiner, Manfred

    2015-10-05

    Copper phthalocyanine (CuPc) blues (PB15) are largely used in art and industry as pigments. In these fields mainly three different polymorphic modifications of PB15 are employed: alpha, beta and epsilon. Differentiating among these CuPc forms can give important information for developing conservation strategy and can help in relative dating, since each form was introduced in the market in different time periods. This study focuses on the classification of Raman spectra measured using 532 nm excitation wavelength on: (i) dry pigment powders, (ii) unaged mock-ups of self-made paints, (iii) unaged commercial paints, and (iv) paints subjected to accelerated UV ageing. The ratios among integrated Raman bands are taken in consideration as features to perform Random Forest (RF). Features selection based on Gini Contrast score was carried out on the measured dataset to determine the Raman bands ratios with higher predictive power. These were used as polymorphic markers, in order to establish an easy and accessible method for the identification. Three different ratios and the presence of a characteristic vibrational band allowed the identification of the crystal modification in pigments powder as well as in unaged and aged paint films.

  13. A novel detection approach based on chromophore-decolorizing with free radical and application to photometric determination of copper with acid chrome dark blue.

    Science.gov (United States)

    Gao, Hong-Wen; Chen, Fang-Fang; Chen, Ling; Zeng, Teng; Pan, Lu-Ting; Li, Jian-Hua; Luo, Hua-Fei

    2007-03-21

    A novel detection approach named chromophore-decolorizing with free radicals is developed for determination of trace heavy metal. The hydroxyl radicals (HO) generated from Fe(III) and hydrogen peroxide will oxidize the free chromophore into almost colorless products. The copper-acid chrome dark blue (ACDB) complexation was investigated at pH 5.07. In the presence of Fe(III) and hydrogen peroxide, the excess ACDB was decolorized in the Cu-ACDB reaction solution, and the final solution contained only one color compound, the Cu-ACDB complex. After oxidation of free hydroxyl radicals, the complexation becomes sensitive and selective and it has been used for the quantitation of trace amounts of Cu(II) dissolved in natural water. Beer's law is obeyed in the range from 0 to 0.500 microg mL(-1) Cu(II) and the limit of detection is only 6 microg L(-1) Cu(II). Besides, the Cu-ACDB complex formed was characterized.

  14. Mixed metal copper(II)-nickel(II) and copper(II)-zinc(II) complexes of multihistidine peptide fragments of human prion protein.

    Science.gov (United States)

    Jószai, Viktória; Turi, Ildikó; Kállay, Csilla; Pappalardo, Giuseppe; Di Natale, Giuseppe; Rizzarelli, Enrico; Sóvágó, Imre

    2012-07-01

    Mixed metal copper(II)-nickel(II) and copper(II)-zinc(II) complexes of four peptide fragments of human prion protein have been studied by potentiometric, UV-vis and circular dichroism spectroscopic techniques. One peptide contained three histidyl residues: HuPrP(84-114) with H85 inside and H96, H111 outside the octarepeat domain. The other three peptides contained two histidyl residues; H96 and H111 for HuPrP(91-115) and HuPrP(84-114)H85A while HuPrP(84-114)H96A contained the histidyl residues at positions 85 and 111. It was found that both histidines of the latter peptides can simultaneously bind copper(II) and nickel(II) ions and dinuclear mixed metal complexes can exist in slightly alkaline solution. One molecule of the peptide with three histidyl residues can bind two copper(II) and one nickel(II) ions. H85 and H111 were identified as the major copper(II) and H96 as the preferred nickel(II) binding sites in mixed metal species. The studies on the zinc(II)-PrP peptide binary systems revealed that zinc(II) ions can coordinate to the 31-mer PrP peptide fragments in the form of macrochelates with two or three coordinated imidazol-nitrogens but the low stability of these complexes cannot prevent the hydrolysis of the metal ion in slightly alkaline solution. These data provide further support for the outstanding affinity of copper(II) ions towards the peptide fragments of prion protein but the binding of nickel(II) can significantly modify the distribution of copper(II) among the available metal binding sites.

  15. Comparison of copper and zinc in vitro bioaccessibility from cyanobacteria rich in proteins and a synthetic supplement containing gluconate complexes: LC-MS mapping of bioaccessible copper complexes.

    Science.gov (United States)

    Wojcieszek, Justyna; Witkoś, Katarzyna; Ruzik, Lena; Pawlak, Katarzyna

    2016-01-01

    An analytical procedure was proposed to estimate bioaccessibility of copper and zinc in Spirulina Pacifica tablets with respect to that of copper and zinc in gluconate complexes. Spirulina is the common name for diet supplements produced primarily from two species of cyanobacteria, namely Arthrospira platensis and Arthrospira maxima. Spirulina tablets are an excellent source of proteins, vitamins and minerals. To obtain information about the bioavailability of these elements, an in vitro bioaccessibility test was performed by application of a two-step protocol which simulated the gastric (pepsin) and intestinal (pancreatin) digestion. The species obtained were investigated by size exclusion chromatography on a chromatograph coupled to a mass spectrometer with inductively coupled plasma (SEC-ICP-MS) and an on-capillary liquid chromatograph coupled to an electrospray mass spectrometer (μ-HPLC-ESI-MS). Both copper and zinc were found to be highly bioaccessible in Spirulina tablets (90-111%) and those containing gluconate complexes (103% for Cu and 62% for Zn). In Spirulina tablets, copper was found to form two types of complex: (1) polar ones with glycine and aspartic acid and (2) more hydrophobic ones containing amino acids with cyclic hydrocarbons (phenylalanine, histidine, proline and tyrosine). Zinc and copper were also proved to form complexes during the digestion process with products of pepsin digestion, but the stability of these complexes is lower than that of the complexes formed in Spirulina. The results proving the involvement of proteins in the enhancement of copper and zinc bioaccessibility will be useful for the design of new copper and zinc supplements.

  16. Arabidopsis copper transport protein COPT2 participates in the cross talk between iron deficiency responses and low-phosphate signaling.

    Science.gov (United States)

    Perea-García, Ana; Garcia-Molina, Antoni; Andrés-Colás, Nuria; Vera-Sirera, Francisco; Pérez-Amador, Miguel A; Puig, Sergi; Peñarrubia, Lola

    2013-05-01

    Copper and iron are essential micronutrients for most living organisms because they participate as cofactors in biological processes, including respiration, photosynthesis, and oxidative stress protection. In many eukaryotic organisms, including yeast (Saccharomyces cerevisiae) and mammals, copper and iron homeostases are highly interconnected; yet, such interdependence is not well established in higher plants. Here, we propose that COPT2, a high-affinity copper transport protein, functions under copper and iron deficiencies in Arabidopsis (Arabidopsis thaliana). COPT2 is a plasma membrane protein that functions in copper acquisition and distribution. Characterization of the COPT2 expression pattern indicates a synergic response to copper and iron limitation in roots. We characterized a knockout of COPT2, copt2-1, that leads to increased resistance to simultaneous copper and iron deficiencies, measured as reduced leaf chlorosis and improved maintenance of the photosynthetic apparatus. We propose that COPT2 could play a dual role under iron deficiency. First, COPT2 participates in the attenuation of copper deficiency responses driven by iron limitation, possibly to minimize further iron consumption. Second, global expression analyses of copt2-1 versus wild-type Arabidopsis plants indicate that low-phosphate responses increase in the mutant. These results open up new biotechnological approaches to fight iron deficiency in crops.

  17. Copper(II) Binding to α-Synuclein, the Parkinson’s Protein

    OpenAIRE

    Lee, Jennifer C.; Gray, Harry B.; Winkler, Jay R.

    2008-01-01

    Variations in tryptophan fluorescence intensities confirm that copper(II) interacts with α-synuclein, a protein implicated in Parkinson’s disease. Trp4 fluorescence decay kinetics measured for the F4W protein show that Cu(II) binds tightly (K d ∼ 100 nM) near the N-terminus at pH 7. Work on a F4W/H50S mutant indicates that a histidine imidazole is not a ligand in this high-affinity site.

  18. Copper transport.

    Science.gov (United States)

    Linder, M C; Wooten, L; Cerveza, P; Cotton, S; Shulze, R; Lomeli, N

    1998-05-01

    In adult humans, the net absorption of dietary copper is approximately 1 mg/d. Dietary copper joins some 4-5 mg of endogenous copper flowing into the gastrointestinal tract through various digestive juices. Most of this copper returns to the circulation and to the tissues (including liver) that formed them. Much lower amounts of copper flow into and out of other major parts of the body (including heart, skeletal muscle, and brain). Newly absorbed copper is transported to body tissues in two phases, borne primarily by plasma protein carriers (albumin, transcuprein, and ceruloplasmin). In the first phase, copper goes from the intestine to the liver and kidney; in the second phase, copper usually goes from the liver (and perhaps also the kidney) to other organs. Ceruloplasmin plays a role in this second phase. Alternatively, liver copper can also exit via the bile, and in a form that is less easily reabsorbed. Copper is also present in and transported by other body fluids, including those bathing the brain and central nervous system and surrounding the fetus in the amniotic sac. Ceruloplasmin is present in these fluids and may also be involved in copper transport there. The concentrations of copper and ceruloplasmin in milk vary with lactational stage. Parallel changes occur in ceruloplasmin messenger RNA expression in the mammary gland (as determined in pigs). Copper in milk ceruloplasmin appears to be particularly available for absorption, at least in rats.

  19. Inhibition of blue-light-dependent binding of 14-3-3 proteins to phototropins by hydrogen peroxide

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao; SHIMAZAKI Kenichiro

    2005-01-01

    @@ Phototropins, following the discovery of phytochromes[1,2] and cryptochromes[3,4], are the most recently characterized blue-light (BL) receptors in plants. The N- terminal regions of the proteins contain two light oxygen and voltage (LOV)――LOV1 and LOV2, which belong to PAS domain involved in protein-protein interaction and ligand binding, possessing non-covalent binding sites for the chromophore FMN[5]. The C-terminal regions contain Ser/Thr kinase domains[6].

  20. Copper chaperone Atox1 interacts with the metal-binding domain of Wilson's disease protein in cisplatin detoxification.

    Science.gov (United States)

    Dolgova, Nataliya V; Nokhrin, Sergiy; Yu, Corey H; George, Graham N; Dmitriev, Oleg Y

    2013-08-15

    Human copper transporters ATP7B (Wilson's disease protein) and ATP7A (Menkes' disease protein) have been implicated in tumour resistance to cisplatin, a widely used anticancer drug. Cisplatin binds to the copper-binding sites in the N-terminal domain of ATP7B, and this binding may be an essential step of cisplatin detoxification involving copper ATPases. In the present study, we demonstrate that cisplatin and a related platinum drug carboplatin produce the same adduct following reaction with MBD2 [metal-binding domain (repeat) 2], where platinum is bound to the side chains of the cysteine residues in the CxxC copper-binding motif. This suggests the same mechanism for detoxification of both drugs by ATP7B. Platinum can also be transferred to MBD2 from copper chaperone Atox1, which was shown previously to bind cisplatin. Binding of the free cisplatin and reaction with the cisplatin-loaded Atox1 produce the same protein-bound platinum intermediate. Transfer of platinum along the copper-transport pathways in the cell may serve as a mechanism of drug delivery to its target in the cell nucleus, and explain tumour-cell resistance to cisplatin associated with the overexpression of copper transporters ATP7B and ATP7A.

  1. Protein-folding location can regulate manganese-binding versus copper- or zinc-binding.

    Science.gov (United States)

    Tottey, Steve; Waldron, Kevin J; Firbank, Susan J; Reale, Brian; Bessant, Conrad; Sato, Katsuko; Cheek, Timothy R; Gray, Joe; Banfield, Mark J; Dennison, Christopher; Robinson, Nigel J

    2008-10-23

    Metals are needed by at least one-quarter of all proteins. Although metallochaperones insert the correct metal into some proteins, they have not been found for the vast majority, and the view is that most metalloproteins acquire their metals directly from cellular pools. However, some metals form more stable complexes with proteins than do others. For instance, as described in the Irving-Williams series, Cu(2+) and Zn(2+) typically form more stable complexes than Mn(2+). Thus it is unclear what cellular mechanisms manage metal acquisition by most nascent proteins. To investigate this question, we identified the most abundant Cu(2+)-protein, CucA (Cu(2+)-cupin A), and the most abundant Mn(2+)-protein, MncA (Mn(2+)-cupin A), in the periplasm of the cyanobacterium Synechocystis PCC 6803. Each of these newly identified proteins binds its respective metal via identical ligands within a cupin fold. Consistent with the Irving-Williams series, MncA only binds Mn(2+) after folding in solutions containing at least a 10(4) times molar excess of Mn(2+) over Cu(2+) or Zn(2+). However once MncA has bound Mn(2+), the metal does not exchange with Cu(2+). MncA and CucA have signal peptides for different export pathways into the periplasm, Tat and Sec respectively. Export by the Tat pathway allows MncA to fold in the cytoplasm, which contains only tightly bound copper or Zn(2+) (refs 10-12) but micromolar Mn(2+) (ref. 13). In contrast, CucA folds in the periplasm to acquire Cu(2+). These results reveal a mechanism whereby the compartment in which a protein folds overrides its binding preference to control its metal content. They explain why the cytoplasm must contain only tightly bound and buffered copper and Zn(2+).

  2. Blue-light dependent inhibition of twitching motility in Acinetobacter baylyi ADP1: Additive involvement of three BLUF domain-containing proteins

    NARCIS (Netherlands)

    Bitrian, M.; Gonzalez, R.H.; Paris, G.; Hellingwerf, K.J.; Nudel, C.B.

    2013-01-01

    Twitching motility in Acinetobacter baylyi ADP1 is inhibited by moderate intensities of blue light in a temperature-dependent manner (maximally at 20 degrees C. We analyzed the involvement of four predicted blue-light-sensing-using flavin (BLUF) domain-containing proteins encoded in the genome of th

  3. The lumenal loop M672-P707 of the Menkes protein (ATP7A) transfers copper to peptidylglycine monooxygenase

    Energy Technology Data Exchange (ETDEWEB)

    Otoikhian, Adenike [Oregon Health & Sciences University; Barry, Amanda N. [Los Alamos National Laboratory; Mayfield, Mary [Oregon Health & Science University; Nilges, Mark [Illinois EPR Center; Huang, Yiping [Johns Hopkins University; Lutsenko, Svetlana [Johns Hopkins University; Blackburn, Ninian [Oregon Health & Science University

    2012-05-14

    Copper transfer to cuproproteins located in vesicular compartments of the secretory pathway depends on activity of the copper translocating ATPase (ATP7A or ATP7B) but the mechanism of transfer is largely unexplored. Copper-ATPase ATP7A is unique in having a sequence rich in histidine and methionine residues located on the lumenal side of the membrane. The corresponding fragment binds Cu(I) when expressed as a chimera with a scaffold protein, and mutations or deletions of His and/or Met residues in its sequence inhibit dephosphorylation of the ATPase, a catalytic step associated with copper release. Here we present evidence for a potential role of this lumenal region of ATP7A in copper transfer to cuproenzymes. Both Cu(II) and Cu(I) forms were investigated since the form in which copper is transferred to acceptor proteins is currently unknown. Analysis of Cu(II) using EPR demonstrated that at Cu:P ratios below 1:1, 15N-substituted protein had Cu(II) bound by 4 His residues, but this coordination changed as the Cu(II) to protein ratio increased towards 2:1. XAS confirmed this coordination via analysis of the intensity of outer-shell scattering from imidazole residues. The Cu(II) complexes could be reduced to their Cu(I) counterparts by ascorbate, but here again, as shown by EXAFS and XANES spectroscopy, the coordination was dependent on copper loading. At low copper Cu(I) was bound by a mixed ligand set of His + Met while at higher ratios His coordination predominated. The copper-loaded loop was able to transfer either Cu(II) or Cu(I) to peptidylglycine monooxygenase in the presence of chelating resin, generating catalytically active enzyme in a process that appeared to involve direct interaction between the two partners. The variation of coordination with copper loading suggests copper-dependent conformational change which in turn could act as a signal for regulating copper release by the ATPase pump.

  4. Potent inhibition of protein tyrosine phosphatases by copper complexes with multi-benzimidazole derivatives.

    Science.gov (United States)

    Li, Ying; Lu, Liping; Zhu, Miaoli; Wang, Qingming; Yuan, Caixia; Xing, Shu; Fu, Xueqi; Mei, Yuhua

    2011-12-01

    A series of copper complexes with multi-benzimidazole derivatives, including mono- and di-nuclear, were synthesized and characterized by Fourier transform IR spectroscopy, UV-Vis spectroscopy, elemental analysis, electrospray ionization mass spectrometry. The speciation of Cu/NTB in aqueous solution was investigated by potentiometric pH titrations. Their inhibitory effects against human protein tyrosine phosphatase 1B (PTP1B), T-cell protein tyrosine phosphatase (TCPTP), megakaryocyte protein tyrosine phosphatase 2 (PTP-MEG2), srchomology phosphatase 1 (SHP-1) and srchomology phosphatase 2 (SHP-2) were evaluated in vitro. The five copper complexes exhibit potent inhibition against PTP1B, TCPTP and PTP-MEG2 with almost same inhibitory effects with IC(50) at submicro molar level and about tenfold weaker inhibition versus SHP-1, but almost no inhibition against SHP-2. Kinetic analysis indicates that they are reversible competitive inhibitors of PTP1B. Fluorescence study on the interaction between PTP1B and complex 2 or 4 suggests that the complexes bind to PTP1B with the formation of a 1:1 complex. The binding constant are about 1.14 × 10(6) and 1.87 × 10(6) M(-1) at 310 K for 2 and 4, respectively.

  5. A doppel alpha-helix peptide fragment mimics the copper(II) interactions with the whole protein.

    Science.gov (United States)

    La Mendola, Diego; Magrì, Antonio; Campagna, Tiziana; Campitiello, Maria Anna; Raiola, Luca; Isernia, Carla; Hansson, Orjan; Bonomo, Raffaele P; Rizzarelli, Enrico

    2010-06-01

    The doppel protein (Dpl) is the first homologue of the prion protein (PrP(C)) to be discovered; it is overexpressed in transgenic mice that lack the prion gene, resulting in neurotoxicity. The whole prion protein is able to inhibit Dpl neurotoxicity, and its N-terminal domain is the determinant part of the protein function. This region represents the main copper(II) binding site of PrP(C). Dpl is able to bind at least one copper ion, and the specific metal-binding site has been identified as the histidine residue at the beginning of the third helical region. However, a reliable characterization of copper(II) coordination features has not been reported. In a previous paper, we studied the copper(II) interaction with a peptide that encompasses only the loop region potentially involved in metal binding. Nevertheless, we did not find a complete match between the EPR spectroscopic parameters of the copper(II) complexes formed with the synthesized peptide and those reported for the copper(II) binding sites of the whole protein. Herein, the synthesis of the human Dpl peptide fragment hDpl(122-139) (Ac-KPDNKLHQQVLWRLVQEL-NH(2)) and its copper(II) complex species are reported. This peptide encompasses the third alpha helix and part of the loop linking the second and the third helix of human doppel protein. The single-point-mutated peptide, hDpl(122-139)D124N, in which aspartate 124 replaces an asparagine residue, was also synthesized. This peptide was used to highlight the role of the carboxylate group on both the conformation preference of the Dpl fragment and its copper(II) coordination features. NMR spectroscopic measurements show that the hDpl(122-139) peptide fragment is in the prevailing alpha-helix conformation. It is localized within the 127-137 amino acid residue region that represents a reliable conformational mimic of the related protein domain. A comparison with the single-point-mutated hDpl(122-139)D124N reveals the significant role played by the aspartic

  6. The non-octarepeat copper binding site of the prion protein is a key regulator of prion conversion

    Science.gov (United States)

    Giachin, Gabriele; Mai, Phuong Thao; Tran, Thanh Hoa; Salzano, Giulia; Benetti, Federico; Migliorati, Valentina; Arcovito, Alessandro; Longa, Stefano Della; Mancini, Giordano; D'Angelo, Paola; Legname, Giuseppe

    2015-10-01

    The conversion of the prion protein (PrPC) into prions plays a key role in transmissible spongiform encephalopathies. Despite the importance for pathogenesis, the mechanism of prion formation has escaped detailed characterization due to the insoluble nature of prions. PrPC interacts with copper through octarepeat and non-octarepeat binding sites. Copper coordination to the non-octarepeat region has garnered interest due to the possibility that this interaction may impact prion conversion. We used X-ray absorption spectroscopy to study copper coordination at pH 5.5 and 7.0 in human PrPC constructs, either wild-type (WT) or carrying pathological mutations. We show that mutations and pH cause modifications of copper coordination in the non-octarepeat region. In the WT at pH 5.5, copper is anchored to His96 and His111, while at pH 7 it is coordinated by His111. Pathological point mutations alter the copper coordination at acidic conditions where the metal is anchored to His111. By using in vitro approaches, cell-based and computational techniques, we propose a model whereby PrPC coordinating copper with one His in the non-octarepeat region converts to prions at acidic condition. Thus, the non-octarepeat region may act as the long-sought-after prion switch, critical for disease onset and propagation.

  7. Elevated copper, hs C-reactive protein and dyslipidemia in drug free schizophrenia: Relation with psychopathology score.

    Science.gov (United States)

    Devanarayanan, Sivasankar; Nandeesha, Hanumanthappa; Kattimani, Shivanand; Sarkar, Siddharth; Jose, Jancy

    2016-12-01

    Inflammation, dyslipidemia and altered copper levels have been reported in several psychiatric disorders, including schizophrenia. However, their association with the severity of psychopathology in schizophrenia is yet to be established. The present study was designed to assess the serum levels of copper, highly sensitive C-reactive protein (hs-CRP) and lipid profile and to explore their association with psychopathology scores in schizophrenia. 40 cases and 40 controls were included in the study. Serum copper, hs-CRP and lipid profile were estimated in all the subjects. Disease severity was assessed using Positive and Negative Syndrome Scale (PANSS). Copper, hs-CRP, total cholesterol and LDL-Cholesterol were significantly increased and HDL-Cholesterol was significantly reduced in schizophrenia cases when compared with controls. Copper was positively correlated with hs-CRP (r=0.338, p=0.003). Total cholesterol was significantly correlated with PANSS total (r=0.452, p=0.003) and negative symptom scores (r=0.337, p=0.033). Triacylglycerol was positively correlated with general psychopathology symptom score (r=0.416, p=0.008). Copper and hs-CRP were increased and correlated well with each other in schizophrenia cases. Though total cholesterol and triacylglycerol showed positive association with severity of the psychopathology, copper and hs-CRP were not associated with the disease severity.

  8. Coordination of platinum therapeutic agents to met-rich motifs of human copper transport protein1.

    Science.gov (United States)

    Crider, Sarah E; Holbrook, Robert J; Franz, Katherine J

    2010-01-01

    Platinum therapeutic agents are widely used in the treatment of several forms of cancer. Various mechanisms for the transport of the drugs have been proposed including passive diffusion across the cellular membrane and active transport via proteins. The copper transport protein Ctr1 is responsible for high affinity copper uptake but has also been implicated in the transport of cisplatin into cells. Human hCtr1 contains two methionine-rich Mets motifs on its extracellular N-terminus that are potential platinum-binding sites: the first one encompasses residues 7-14 with amino acid sequence Met-Gly-Met-Ser-Tyr-Met-Asp-Ser and the second one spans residues 39-46 with sequence Met-Met-Met-Met-Pro-Met-Thr-Phe. In these studies, we use liquid chromatography and mass spectrometry to compare the binding interactions between cisplatin, carboplatin and oxaliplatin with synthetic peptides corresponding to hCtr1 Mets motifs. The interactions of cisplatin and carboplatin with Met-rich motifs that contain three or more methionines result in removal of the carrier ligands of both platinum complexes. In contrast, oxaliplatin retains its cyclohexyldiamine ligand upon platinum coordination to the peptide.

  9. Copper-binding peptides from human prion protein and newly designed peroxidative biocatalysts.

    Science.gov (United States)

    Kagenishi, Tomoko; Yokawa, Ken; Kadono, Takashi; Uezu, Kazuya; Kawano, Tomonori

    2011-01-01

    A previous work suggested that peptides from the histidine-containing copper-binding motifs in human prion protein (PrP) function as peroxidase-like biocatalysts catalyzing the generation of superoxide anion radicals in the presence of neurotransmitters (aromatic monoamines) and phenolics such as tyrosine and tyrosyl residues on proteins. In this study, using various phenolic substrates, the phenol-dependent superoxide-generating activities of PrP-derived peptide sequences were compared. Among the peptides tested, the GGGTH pentapeptide was shown to be the most active catalyst for phenol-dependent reactions. Based on these results, we designed a series of oligoglycyl-histidines as novel peroxidative biocatalysts, and their catalytic performances including kinetics, heat tolerance, and freezing tolerance were analysed.

  10. The influence of cross-linking on protein-protein interactions in a marine adhesive: the case of two byssus plaque proteins from the blue mussel.

    Science.gov (United States)

    Fant, Camilla; Elwing, Hans; Höök, Fredrik

    2002-01-01

    The interaction between two proteins, Mefp-1 and Mefp-2, from the byssal plaque of the blue mussel, Mytilus edulis, was investigated using a quartz crystal microbalance with dissipation monitoring (QCM-D) technique. The challenge in using a surface-sensitive technique to investigate the interaction between two strongly adhesive proteins was met by coupling a biotinylated version of one of the proteins (b-Mefp-1) to an inert two-dimensional arrangement of streptavidin (SA) formed on top of a biotin-doped supported phospholipid bilayer. The interaction between Mefp-1 and Mefp-2 was further investigated by addition of Mefp-2 to SA-coupled b-Mefp-1, where the latter was either in the native state or cross-linked using sodium periodate (NaIO(4)), Cu(2+), or mushroom tyrosinase. With this coupling strategy it is shown that a requirement for attraction between the two proteins is that tyrosinase is used as the cross-linking agent of b-Mefp-1. By inhibiting the enzymatic activity of tyrosinase it is also shown that enzymatic activity is required for both efficient binding of tyrosinase to SA-coupled b-Mefp-1 as well as for the subsequent binding of Mefp-2. In contrast, spontaneous adsorption of Mefp-1 to a methyl-terminated (thiolated) gold surface followed by addition of Mefp-2 results in binding of Mefp-2 for all cross-linking agents. This suggests that cross-linking of Mefp-1 adsorbed on a solid surface induces structural changes in the adsorbed protein layer, resulting in exposure of free surface patches on which Mefp-2 binds.

  11. Investigation on Molecular Non-covalent Interaction in the Sodium Dodecyl Benzene Sulfonatepolychrome Blue B-protein Replacement Reaction

    Institute of Scientific and Technical Information of China (English)

    GAO,Hong-Wen(郜洪文); WU,Ji-Rong(邬继荣); SHEN,Rong(沈荣)

    2004-01-01

    The molecular non-covalent interaction often originates from the electrostatic attraction and accords with the Langmuir isothermal adsorption. The sodium dodecyl benzene sulfonate (SDBS)-polychrome blue B (PCB)-protein [bovine serum albumin (BSA), ovalbumin (OVA) and myoglobin (MB)] ternary reaction has been investigated at Ph 3.88. Protein to replace PCB from the PCB-SDBS binding product was used to characterize the assembly of an invisible-spectral compound, SDBS, on proteins by measuring the variation of PCB light-absorption by the microsurface adsorption-spectral correction (MSASC) technique. The effect of ionic strength and temperature on the aggregation was studied. Results showed that the aggregates SDBS92·BSA, SDBS58·OVA and SDBS15·MB at 30 ℃ and SDBS83·BSA, SDBS39·OVA and SDBS10·MB at 50 ℃ are formed.

  12. Predicting copper-, iron- and zinc-binding proteins in pathogenic species of the Paracoccidioides genus

    Directory of Open Access Journals (Sweden)

    Gabriel B Tristao

    2015-01-01

    Full Text Available Approximately one-third of all proteins have been estimated to contain at least one metal cofactor, and these proteins are referred to as metalloproteins. These represent one of the most diverse classes of proteins, containing metal ions that bind to specific sites to perform catalytic, regulatory and structural functions. Bioinformatic tools have been developed to predict metalloproteins encoded by an organism based only on its genome sequence. Its function and the type of metal binder can also be predicted via a bioinformatics approach. Paracoccidioides complex includes termodimorphic pathogenic fungi that are found as saprobic mycelia in the environment and as yeast, the parasitic form, in host tissues. They are the etiologic agents of Paracoccidioidomycosis, a prevalent systemic mycosis in Latin America. Many metalloproteins are important for the virulence of several pathogenic microorganisms. Accordingly, the present work aimed to predict the cooper, iron and zinc proteins encoded by the genomes of three phylogenetic species of Paracoccidioides (Pb01, Pb03 and Pb18. The metalloproteins were identified using bioinformatics approaches based on structure, annotation and domains. Cu-, Fe- and Zn-binding proteins represent 7% of the total proteins encoded by Paracoccidioides spp. genomes. Zinc proteins were the most abundant metalloproteins, representing 5.7% of the fungus proteome, whereas copper and iron proteins represent 0.3% and 1.2%, respectively. Functional classification revealed that metalloproteins are related to many cellular processes. Furthermore, it was observed that many of these metalloproteins serve as virulence factors in the biology of the fungus. Thus, it is concluded that the Cu, Fe and Zn metalloproteomes of the Paracoccidioides spp. are of the utmost importance for the biology and virulence of these particular human pathogens.

  13. The CopC Family: Structural and Bioinformatic Insights into a Diverse Group of Periplasmic Copper Binding Proteins.

    Science.gov (United States)

    Lawton, Thomas J; Kenney, Grace E; Hurley, Joseph D; Rosenzweig, Amy C

    2016-04-19

    The CopC proteins are periplasmic copper binding proteins believed to play a role in bacterial copper homeostasis. Previous studies have focused on CopCs that are part of seven-protein Cop or Pco systems involved in copper resistance. These canonical CopCs contain distinct Cu(I) and Cu(II) binding sites. Mounting evidence suggests that CopCs are more widely distributed, often present only with the CopD inner membrane protein, frequently as a fusion protein, and that the CopC and CopD proteins together function in the uptake of copper to the cytoplasm. In the methanotroph Methylosinus trichosporium OB3b, genes encoding a CopCD pair are located adjacent to the particulate methane monooxygenase (pMMO) operon. The CopC from this organism (Mst-CopC) was expressed, purified, and structurally characterized. The 1.46 Å resolution crystal structure of Mst-CopC reveals a single Cu(II) binding site with coordination somewhat different from that in canonical CopCs, and the absence of a Cu(I) binding site. Extensive bioinformatic analyses indicate that the majority of CopCs in fact contain only a Cu(II) site, with just 10% of sequences corresponding to the canonical two-site CopC. Accordingly, a new classification scheme for CopCs was developed, and detailed analyses of the sequences and their genomic neighborhoods reveal new proteins potentially involved in copper homeostasis, providing a framework for expanded models of CopCD function.

  14. Blue-light mediated accumulation of nuclear-encoded transcripts coding for proteins of the thylakoid membrane is absent in the phytochrome-deficient aurea mutant of tomato.

    Science.gov (United States)

    Oelmüller, R; Kendrick, R E; Briggs, W R

    1989-08-01

    Polyclonal antibodies against pea phytochrome detect 2 protein bands (about 116 and 120 kDa) on blots of crude protein extracts and protein of microsomal preparations of dark-grown tomato seedlings. Both protein bands are undetectable in Western blots of the aurea mutant extracts. Neither protein band is detectable after isogenic wild-type seedlings are illuminated with 3 h of red light, either in the crude extract or in the membrane fraction of the irradiated seedlings; this result is consistent with the hypothesis that both bands are phytochrome. When dark-grown wild-type seedlings are illuminated with 3 h of red light or blue light against a red light background, the transcript levels for chlorophyll a/b-binding proteins of photosystem I and II, plastocyanin, and the subunit II of photosystem I increase. In all cases, the same fluence rate of blue light is much more effective than red light alone, a result that indicates the involvement of a blue/UV-A light photoreceptor in addition to the involvement of the far-red-absorbing form of phytochrome, Pfr. The aurea mutant responds neither to red light nor to blue light. Thus, no Pfr-independent induction of the four transcripts by a blue/UV-A light photoreceptor can be measured in the aurea mutant.

  15. Mechanism of copper(II)-induced misfolding of Parkinson's disease protein.

    Science.gov (United States)

    Rose, Frisco; Hodak, Miroslav; Bernholc, Jerzy

    2011-01-01

    α-synuclein (aS) is a natively unfolded pre-synaptic protein found in all Parkinson's disease patients as the major component of fibrillar plaques. Metal ions, and especially Cu(II), have been demonstrated to accelerate aggregation of aS into fibrillar plaques, the precursors to Lewy bodies. In this work, copper binding to aS is investigated by a combination of quantum and molecular mechanics simulations. Starting from the experimentally observed attachment site, several optimized structures of Cu-binding geometries are examined. The most energetically favorable attachment results in significant allosteric changes, making aS more susceptible to misfolding. Indeed, an inverse kinematics investigation of the configuration space uncovers a dynamically stable β-sheet conformation of Cu-aS that serves as a nucleation point for a second β-strand. Based on these findings, we propose an atomistic mechanism of copper-induced misfolding of aS as an initial event in the formation of Lewy bodies and thus in PD pathogenesis.

  16. Copper attachment to prion protein at a non-octarepeat site

    Science.gov (United States)

    Hodak, Miroslav; Bernholc, Jerry

    2011-03-01

    Prion protein (PrP) plays a causative role in a group of neurodegenerative diseases, which include ``mad cow disease'' or its human form variant Creutzfeld-Jacob disease. Normal function of PrP remains unknown, but it is now well established that PrP can efficiently bind copper ions and this ability has been linked to its function. The primary binding sites are located in the so-called octarepeat region located between residues 60-91. While these are by now well characterized, the sites located outside these region remain mostly undetermined. In this work, we investigate the properties of Cu binding site located at His 111 using recently developed hybrid Kohn-Sham/orbital-free density functional simulations. Experimental data indicate that copper is coordinated by either four nitrogens or three nitrogens and one oxygen. We investigate both possibilities, comparing their energetics and attachment geometries. Similarities and differences with other binding sites and implications for PrP function will also be discussed.

  17. Blue light is required for survival of the tomato phytochrome-deficient aurea mutant and the expression of four nuclear genes coding for plastidic proteins.

    Science.gov (United States)

    Oelmüller, R; Kendrick, R E

    1991-02-01

    When dark-grown aurea mutant tomato seedlings which lack more than 95% of the phytochrome present in isogenic wild-type seedlings are kept in white or blue light, four nuclear-encoded transcripts coding for plastidic proteins (the light-harvesting chlorophyll a/b-binding protein of photosystem I and II [cab-PSII], plastocyanin and subunit 2 of photosystem I) are present in comparable amounts. These transcript levels in red light are strongly reduced in aurea seedlings when compared with those of wild type. Thus, blue light is required for normal expression of these genes in the mutant, while red light alone is not sufficient. Red light-grown aurea seedlings are very sensitive to blue light, even 10 minutes of blue light every day suffices to cause a measurable increase in cab-PSII transcript level. The action of blue light on the expression of cab-PSII in the mutant is under phytochrome control. After 8 days of blue light, phytochrome is almost as effective in inducing cab-PSII mRNA as in the isogenic wild type, whereas after 8 days of red light, only a small phytochrome response was observed in the mutant. It is concluded that blue light sensitizes the mutant to the residual phytochrome which allows normal gene expression and survival of the mutant under daylight conditions.

  18. Wilson Disease Protein ATP7B Utilizes Lysosomal Exocytosis to Maintain Copper Homeostasis

    NARCIS (Netherlands)

    Polishchuk, Elena V.; Concilli, Mafalda; Iacobacci, Simona; Chesi, Giancarlo; Pastore, Nunzia; Piccolo, Pasquale; Paladino, Simona; Baldantoni, Daniela; van IJzendoorn, Sven C. D.; Chan, Jefferson; Chang, Christopher J.; Amoresano, Angela; Pane, Francesca; Pucci, Piero; Tarallo, Antonietta; Parenti, Giancarlo; Brunetti-Pierri, Nicola; Settembre, Carmine; Ballabio, Andrea; Polishchuk, Roman S.

    2014-01-01

    Copper is an essential yet toxic metal and its overload causes Wilson disease, a disorder due to mutations in copper transporter ATP7B. To remove excess copper into the bile, ATP7B traffics toward canalicular area of hepatocytes. However, the trafficking mechanisms of ATP7B remain elusive. Here, we

  19. Copper increases the damage to DNA and proteins caused by reactive oxygen species.

    Science.gov (United States)

    Cervantes-Cervantes, Martha Patricia; Calderón-Salinas, J Víctor; Albores, Arnulfo; Muñoz-Sánchez, José Luis

    2005-03-01

    Copper [Cu(II)] is an ubiquitous transition and trace element in living organisms. It increases reactive oxygen species (ROS) and free-radical generation that might damage biomolecules like DNA, proteins, and lipids. Furthermore, ability of Cu(II) greatly increases in the presence of oxidants. ROS, like hydroxyl (.OH) and superoxide (.O(2)) radicals, alter both the structure of the DNA double helix and the nitrogen bases, resulting in mutations like the AT-->GC and GC-->AT transitions. Proteins, on the other hand, suffer irreversible oxidations and loss in their biological role. Thus, the aim of this investigation is to characterize, in vitro, the structural effects caused by ROS and Cu(II) on bacteriophage lambda DNA or proteins using either hydrogen peroxide (H(2)O(2)) or ascorbic acid with or without Cu(II). Exposure of DNA to ROS-generating mixtures results in electrophoretic (DNA breaks), spectrophotometric (band broadening, hypochromic, hyperchromic, and bathochromic effects), and calorimetric (denaturation temperature [T(d)], denaturation enthalpy [DeltaH], and heat capacity [C(p)] values) changes. As for proteins, ROS increased their thermal stability. However, the extent of the observed changes in DNA and proteins were distinct, depending on the efficiency of the systems assayed to generate ROS. The resulting effects were most evident when Cu(II) was present. In summary, these results show that the ROS, .O2 and .OH radicals, generated by the Cu(II) systems assayed deeply altered the chemical structure of both DNA and proteins. The physiological relevance of these structural effects should be further investigated.

  20. Peculiar reactivity of a di-imine copper(II) complex regarding its binding to albumin protein.

    Science.gov (United States)

    Silveira, Vivian C; Abbott, Mariana P; Cavicchioli, Maurício; Gonçalves, Marcos B; Petrilli, Helena M; de Rezende, Leandro; Amaral, Antonia T; Fonseca, David E P; Caramori, Giovanni F; Ferreira, Ana M da Costa

    2013-05-14

    A set of four di-imine copper(II) complexes containing pyridine, pyrazine and/or imidazole moieties, [Cu(apyhist)H2O](2+) 1 (apyhist = 2-(1H-imidazol-4-yl)-N-(1-(pyridin-2-yl)ethylidene)ethanamine), [Cu(apzhist)OH](+) 2 (apzhist = 2-(1H-imidazol-4-yl)-N-(1-(pyrazin-2-yl)ethylidene)ethanamine), [Cu(apyepy)OH](+) 3 (apyepy = 2-(pyridin-2-yl)-N-(1-(pyridin-2-yl)ethylidene)ethanamine), and [Cu(apzepy)H2O](2+) 4 (apzepy = N-(1-(pyrazin-2-yl)ethylidene)-2-(pyridin-2-yl)ethanamine), were investigated regarding their capability of interacting with serum albumin (human, HSA and bovine, BSA), by using spectroscopic techniques, CD, UV/Vis and EPR. Like other similar di-imine copper(II) complexes, most of them showed an expected preferential insertion of the metal ion at the primary N-terminal site of the protein, very selective for copper and characterized by a CD band at 560 nm. Further insertion of the copper ion at a secondary site is expected when using an excess of the metal. However, one of these studied complexes, [Cu(apyhist)H2O](2+) 1, exhibited anomalous behaviour interacting only at this secondary metal binding site of albumin, characterized by a CD band at 370 nm, and attributed to the coordination of copper at the Cys34 pocket. Analogous experiments with HSA previously treated with N-ethyl-maleimide (NEM), that oxidizes the protein Cys34 residue and obstructs the metal coordination, verified these results. Additional data obtained by EPR spectroscopy complemented those results. DFT calculations, considering some structural and electronic characteristics of such series of di-imine ligands and of the corresponding copper complexes, suggested molecular recognition of the apyhist ligand at the protein cavity as a feasible explanation for this unexpected and peculiar behaviour of complex 1.

  1. Function and Regulation of the Plant COPT Family of High-Affinity Copper Transport Proteins

    Directory of Open Access Journals (Sweden)

    Sergi Puig

    2014-01-01

    Full Text Available Copper (Cu is an essential micronutrient for all eukaryotes because it participates as a redox active cofactor in multiple biological processes, including mitochondrial respiration, photosynthesis, oxidative stress protection, and iron (Fe transport. In eukaryotic cells, Cu transport toward the cytoplasm is mediated by the conserved CTR/COPT family of high-affinity Cu transport proteins. This outlook paper reviews the contribution of our research group to the characterization of the function played by the Arabidopsis thaliana COPT1–6 family of proteins in plant Cu homeostasis. Our studies indicate that the different tissue specificity, Cu-regulated expression, and subcellular localization dictate COPT-specialized contribution to plant Cu transport and distribution. By characterizing lack-of-function Arabidopsis mutant lines, we conclude that COPT1 mediates root Cu acquisition, COPT6 facilitates shoot Cu distribution, and COPT5 mobilizes Cu from storage organelles. Furthermore, our work with copt2 mutant and COPT-overexpressing plants has also uncovered Cu connections with Fe homeostasis and the circadian clock, respectively. Future studies on the interaction between COPT transporters and other components of the Cu homeostasis network will improve our knowledge of plant Cu acquisition, distribution, regulation, and utilization by Cu-proteins.

  2. Construction and characterization of an azurin analog for the purple copper site in cytochrome c oxidase.

    Science.gov (United States)

    Hay, M; Richards, J H; Lu, Y

    1996-01-09

    A protein analog of a purple copper center has been constructed from a recombinant blue copper protein (Pseudomonas aeruginosa azurin) by replacing the loop containing the three ligands to the blue copper center with the corresponding loop of the CuA center in cytochrome c oxidase (COX) from Paracoccus denitrificans. The electronic absorption in the UV and visible region (UV-vis) and electron paramagnetic resonance (EPR) spectra of this analog are remarkably similar to those of the native CuA center in COX from Paracoccus denitrificans. The above spectra can be obtained upon addition of a mixture of Cu2+ and Cu+. Addition of Cu2+ only results in a UV-vis spectrum consisting of absorptions from both a purple copper center and a blue copper center. This spectrum can be converted to the spectrum of a pure purple copper by a prolonged incubation in the air, or by addition of excess ascorbate. The azurin mutant reported here is an example of an engineered purple copper center with the A480/A530 ratio greater than 1 and with no detectable hyperfines, similar to those of the CuA sites in COX of bovine heart and of Paracoccus denitrificans.

  3. Carotenoid-based plumage colouration is associated with blood parasite richness and stress protein levels in blue tits (Cyanistes caeruleus).

    Science.gov (United States)

    del Cerro, Sara; Merino, Santiago; Martínez-de la Puente, Josué; Lobato, Elisa; Ruiz-de-Castañeda, Rafael; Rivero-de Aguilar, Juan; Martínez, Javier; Morales, Judith; Tomás, Gustavo; Moreno, Juan

    2010-04-01

    Carotenoids are molecules that birds are not able to synthesize and therefore, must be acquired through their diet. These pigments, besides their function of giving birds red and yellow colouration when deposited in feathers, seem to act as immune-stimulators and antioxidants in the organism. Hence, only the healthiest individuals would be able to express carotenoid-based ornaments to a larger extent without compromising the physiological functions of carotenoids. Various studies have reported that birds infected by parasites are paler than those uninfected, but, to our knowledge, none of them has assessed the possible effect of multiple infections by blood parasites on plumage colour. By comparing the yellow colour in the breast plumage of blue tits, Cyanistes caeruleus, between birds infected by different numbers of blood parasite genera, we found that those birds infected by more than one genus were paler than those parasitized just by one. In addition, we examined the potential role of carotenoid-based plumage colour of blue tits as a long-term indicator of other parameters of health status, such as body condition and immunoglobulin and heat shock protein (HSP) levels. Our results indicate that more brightly coloured birds had lower HSP70 levels than paler birds, but we did not find any significant association between colour and body condition or immunoglobulin levels. In addition, we found a positive significant association between Haemoproteus density of infection and HSP60 levels. Overall, these results support the role of carotenoid-based colours as indicators of health status in blue tits and show detrimental effects of parasitism on this character.

  4. Effect of copper on the characterization of proteins in the Spiny lobster, Panulirus homarus homarus (Linnaeus,1758

    Directory of Open Access Journals (Sweden)

    Maharajan Athisuyambulingam

    2014-07-01

    Full Text Available Copper is most toxic metal in marine organisms. Characterization of protein occurring in the metabolically active tissues of muscle (MU, hepatopancreas (HP and gills (GL of the spiny lobster, Panulirus homarus homarus on exposure to two sub-lethal doses (9.55 and 19.1 µg/l of copper were studied for 28 days of exposure (DoE. The electrophoretic pattern of muscle, hepatopancreas and gill proteins revealed 12, 8 and 8 slow moving bands (control. The number of bands decreased to 8 and 7, 6 and 5, 6 and 4 after 7 days of exposure to 9.55 µg/l and 19.1 µg/l concentrations of copper, respectively. After 28 days, the protein bands decreased to 7 and 6, 5 and 4, 4 and 4 at 9.55 µg/l and 19.1 µg/l concentrations of copper, respectively. Present study to indicate that to avoid the Cupro-Nickel coil in lobster holding centers in chiller plants used for cooling of water was found to be responsible for the mortality of lobsters during live transportation.

  5. Proteomic analysis of copper-binding proteins in excess copper-stressed rice roots by immobilized metal affinity chromatography and two-dimensional electrophoresis.

    Science.gov (United States)

    Song, Yufeng; Zhang, Hongxiao; Chen, Chen; Wang, Guiping; Zhuang, Kai; Cui, Jin; Shen, Zhenguo

    2014-04-01

    Copper (Cu) is an essential micronutrient required for plant growth and development. However, excess Cu can inactivate and disturb protein structure as a result of unavoidable binding to proteins. To understand better the mechanisms involved in Cu toxicity and tolerance in plants, we developed a new immobilized metal affinity chromatography (IMAC) method for the separation and isolation of Cu-binding proteins extracted from roots of rice seedling exposed to excess Cu. In our method, IDA-Sepharose or EDDS-Sepharose column (referred as pre-chromatography) and Cu-IDA-Sepharose column (referred as Cu-IMAC) were connected in tandem. Namely, protein samples were pre-chromatographed with IDA-Sepharose column to removal metal ions, then protein solution was flowed into Cu-IMAC column for enriching Cu-binding proteins in vitro. Compared with the control (Cu-IMAC without any pre-chromatography), IDA-Sepharose pre-chromatography method markedly increased yield of the Cu-IMAC-binding proteins, and number of protein spots and the abundance of 40 protein spots on two-dimensional electrophoresis (2-DE) gels. Thirteen protein spots randomly selected from 2-DE gel and 11 proteins were identified using MALDI-TOF-TOF MS. These putative Cu-binding proteins included those involved in antioxidant defense, carbohydrate metabolism, nucleic acid metabolism, protein folding and stabilization, protein transport and cell wall synthesis. Ten proteins contained one or more of nine putative metal-binding motifs reported by Smith et al. (J Proteome Res 3:834-840, 2004) and seven proteins contained one or two of top six motifs reported by Kung et al. (Proteomics 6:2746-2758, 2006). Results demonstrated that more proteins specifically bound with Cu-IMAC could be enriched through removal of metal ions from samples by IDA-Sepharose pre-chromatography. Further studies are needed on metal-binding characteristics of these proteins in vivo and the relationship between Cu ions and protein biological

  6. Ionic self-complementarity induces amyloid-like fibril formation in an isolated domain of a plant copper metallochaperone protein

    Directory of Open Access Journals (Sweden)

    Salom David

    2004-06-01

    Full Text Available Abstract Background Arabidopsis thaliana copper metallochaperone CCH is a functional homologue of yeast antioxidant ATX1, involved in cytosolic copper transport. In higher plants, CCH has to be transported to specialised cells through plasmodesmata, being the only metallochaperone reported to date that leaves the cell where it is synthesised. CCH has two different domains, the N-terminal domain conserved among other copper-metallochaperones and a C-terminal domain absent in all the identified non-plant metallochaperones. The aim of the present study was the biochemical and biophysical characterisation of the C-terminal domain of the copper metallochaperone CCH. Results The conformational behaviour of the isolated C-domain in solution is complex and implies the adoption of mixed conformations in different environments. The ionic self-complementary peptide KTEAETKTEAKVDAKADVE, derived from the C-domain of CCH, adopts and extended conformation in solution with a high content in β-sheet structure that induces a pH-dependent fibril formation. Freeze drying electron microscopy studies revealed the existence of well ordered amyloid-like fibrils in preparations from both the C-domain and its derivative peptide. Conclusion A number of proteins related with copper homeostasis have a high tendency to form fibrils. The determinants for fibril formation, as well as the possible physiological role are not fully understood. Here we show that the plant exclusive C-domain of the copper metallochaperone CCH has conformational plasticity and forms fibrils at defined experimental conditions. The putative influence of these properties with plant copper delivery will be addressed in the future.

  7. Distribution and phylogeny of light-oxygen-voltage-blue-light-signaling proteins in the three kingdoms of life.

    Science.gov (United States)

    Krauss, Ulrich; Minh, Bui Quang; Losi, Aba; Gärtner, Wolfgang; Eggert, Thorsten; von Haeseler, Arndt; Jaeger, Karl-Erich

    2009-12-01

    Plants and fungi respond to environmental light stimuli via the action of different photoreceptor modules. One such class, responding to the blue region of light, is constituted by photoreceptors containing so-called light-oxygen-voltage (LOV) domains as sensor modules. Four major LOV families are currently identified in eukaryotes: (i) the plant phototropins, regulating various physiological effects such as phototropism, chloroplast relocation, and stomatal opening; (ii) the aureochromes, mediating photomorphogenesis in photosynthetic stramenopile algae; (iii) the plant circadian photoreceptors of the zeitlupe (ZTL)/adagio (ADO)/flavin-binding Kelch repeat F-box protein 1 (FKF1) family; and (iv) the fungal circadian photoreceptors white-collar 1 (WC-1). Blue-light-sensitive LOV signaling modules are also widespread throughout the prokaryotic world, and physiological responses mediated by bacterial LOV photoreceptors were recently reported. Thus, the question arises as to the evolutionary relationship between the pro- and eukaryotic LOV photoreceptor systems. We used Bayesian and maximum-likelihood tree reconstruction methods to infer evolutionary scenarios that might have led to the widespread appearance of LOV domains among the pro- and eukaryotes. The phylogenetic study presented here suggests a bacterial origin for the LOV domains of the four major eukaryotic LOV photoreceptor families, whereas the LOV sensor domains were most likely recruited from the bacteria in the course of plastid and mitochondrial endosymbiosis.

  8. An improved Coomassie Brilliant Blue (CBB R-250) staining to proteins in gels

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    An improved CBB staining with higher sensitivity than that of the typical CBB staining was reported. The main improvement was using a fixing step of 25% trichloroacetic acid (TCA) before CBB staining. For most proteins studied, the sensitivity of the improved CBB staining was about twice as high as that of the typical method. For basic and low molecular weight proteins such as ribosomal proteins, the sensitivity of this improved staining method was about 3.5-28 times that of the typical method. It was speculated that the improved procedure would be suitable for exact quantitative analysis of proteins fractionated by SDS-PAGE, especially for basic and low molecular weight proteins. On the other hand, this new modified method might be also applied to multidisciplinary studies, such as biological researches and nuclear sciences.

  9. The Copper Metabolism MURR1 domain protein 1 (COMMD1 modulates the aggregation of misfolded protein species in a client-specific manner.

    Directory of Open Access Journals (Sweden)

    Willianne I M Vonk

    Full Text Available The Copper Metabolism MURR1 domain protein 1 (COMMD1 is a protein involved in multiple cellular pathways, including copper homeostasis, NF-κB and hypoxia signalling. Acting as a scaffold protein, COMMD1 mediates the levels, stability and proteolysis of its substrates (e.g. the copper-transporters ATP7B and ATP7A, RELA and HIF-1α. Recently, we established an interaction between the Cu/Zn superoxide dismutase 1 (SOD1 and COMMD1, resulting in a decreased maturation and activation of SOD1. Mutations in SOD1, associated with the progressive neurodegenerative disorder Amyotrophic Lateral Sclerosis (ALS, cause misfolding and aggregation of the mutant SOD1 (mSOD1 protein. Here, we identify COMMD1 as a novel regulator of misfolded protein aggregation as it enhances the formation of mSOD1 aggregates upon binding. Interestingly, COMMD1 co-localizes to the sites of mSOD1 inclusions and forms high molecular weight complexes in the presence of mSOD1. The effect of COMMD1 on protein aggregation is client-specific as, in contrast to mSOD1, COMMD1 decreases the abundance of mutant Parkin inclusions, associated with Parkinson's disease. Aggregation of a polyglutamine-expanded Huntingtin, causative of Huntington's disease, appears unaltered by COMMD1. Altogether, this study offers new research directions to expand our current knowledge on the mechanisms underlying aggregation disease pathologies.

  10. The Copper Metabolism MURR1 domain protein 1 (COMMD1) modulates the aggregation of misfolded protein species in a client-specific manner.

    Science.gov (United States)

    Vonk, Willianne I M; Kakkar, Vaishali; Bartuzi, Paulina; Jaarsma, Dick; Berger, Ruud; Hofker, Marten H; Klomp, Leo W J; Wijmenga, Cisca; Kampinga, Harm H; van de Sluis, Bart

    2014-01-01

    The Copper Metabolism MURR1 domain protein 1 (COMMD1) is a protein involved in multiple cellular pathways, including copper homeostasis, NF-κB and hypoxia signalling. Acting as a scaffold protein, COMMD1 mediates the levels, stability and proteolysis of its substrates (e.g. the copper-transporters ATP7B and ATP7A, RELA and HIF-1α). Recently, we established an interaction between the Cu/Zn superoxide dismutase 1 (SOD1) and COMMD1, resulting in a decreased maturation and activation of SOD1. Mutations in SOD1, associated with the progressive neurodegenerative disorder Amyotrophic Lateral Sclerosis (ALS), cause misfolding and aggregation of the mutant SOD1 (mSOD1) protein. Here, we identify COMMD1 as a novel regulator of misfolded protein aggregation as it enhances the formation of mSOD1 aggregates upon binding. Interestingly, COMMD1 co-localizes to the sites of mSOD1 inclusions and forms high molecular weight complexes in the presence of mSOD1. The effect of COMMD1 on protein aggregation is client-specific as, in contrast to mSOD1, COMMD1 decreases the abundance of mutant Parkin inclusions, associated with Parkinson's disease. Aggregation of a polyglutamine-expanded Huntingtin, causative of Huntington's disease, appears unaltered by COMMD1. Altogether, this study offers new research directions to expand our current knowledge on the mechanisms underlying aggregation disease pathologies.

  11. Structural diversity of a collagen-binding matrix protein from the byssus of blue mussels upon refolding.

    Science.gov (United States)

    Suhre, Michael H; Scheibel, Thomas

    2014-04-01

    Blue mussels firmly adhere to a variety of different substrates by the byssus, an extracorporal structure consisting of several protein threads. These threads are mainly composed of fibrillar collagens called preCols which are embedded in a proteinaceous matrix. One of the two so far identified matrix proteins is the Proximal Thread Matrix Protein 1 (PTMP1). PTMP1 comprises two von Willebrand factor type A-like domains (A1 and A2) in a special arrangement. Here, we describe the refolding of recombinant PTMP1 from inclusion bodies. PTMP1 refolded into two distinct monomeric isoforms. Both isomers exhibited alternative intramolecular disulfide bonds. One of these isomers is thermodynamically favored and presumably represents the native form of PTMP1, while the other isoform is kinetically favored but is likely non-native. Oligomerization during refolding was influenced by, but not strictly dependent on disulfide formation. The conformational stability of PTMP1 indicates an influence of intramolecular disulfides on the native state, but not on unfolding intermediates. Monomeric PTMP1 exhibited a high thermal stability, dependent on the pH of the surrounding environment. Especially under acidic conditions the disulfide bonds were critically involved in thermal stability.

  12. Integration of XAS and NMR techniques for the structure determination of metalloproteins. Examples from the study of copper transport proteins.

    Science.gov (United States)

    Banci, Lucia; Bertini, Ivano; Mangani, Stefano

    2005-01-01

    Nuclear magnetic resonance (NMR) is a powerful technique for protein structure determination in solution. However, when dealing with metalloproteins, NMR methods are unable to directly determine the structure of the metal site and its coordination geometry. The capability of X-ray absorption spectroscopy (XAS) to provide the structure of a metal ion bound to a protein is then perfectly suited to complement the process of the structure determination. This aspect is particularly relevant in structural genomic projects where high throughput of structural results is the main goal. The synergism of the two techniques has been exploited in the structure determination of bacterial copper transport proteins.

  13. From Green to Blue: Site-Directed Mutagenesis of the Green Fluorescent Protein to Teach Protein Structure-Function Relationships

    Science.gov (United States)

    Giron, Maria D.; Salto, Rafael

    2011-01-01

    Structure-function relationship studies in proteins are essential in modern Cell Biology. Laboratory exercises that allow students to familiarize themselves with basic mutagenesis techniques are essential in all Genetic Engineering courses to teach the relevance of protein structure. We have implemented a laboratory course based on the…

  14. Copper-mediated oxidative degradation of catecholamines and oxidative damage of protein

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, P.R.; Harria, M.I.N.; Felix, J.M.; Hoffmann, M.E. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Biologia

    1997-12-31

    Full text. Degradative oxidation of catecholamines has been a matter of large interest in recent years due to the evidences associating their autoxidation with the etiology of neurotoxic and cardiotoxic processes. In this work we present data on the degradative oxidation of catecholamines of physiological importance: isoproterenol (IP), epinephrine (EP), norepinephrine (NEP), deoxyepinephrine (DEP) and dopamine (DA). The degradative oxidation of the catecholamines was followed by measurement of spectral changes and oxygen consumption by neutral aqueous solutions. The data show that Cu{sup 2+} strongly accelerated the rate of catecholamine oxidation, following the decreasing order; EP>DEP>IP>NEP>DA. The production of superoxide anion radical during catecholamine oxidation was very slow, even in the presence of Cu{sup 2+}. The ability of IP to induce damages on bovine serum albumin (BSA) was determined by measuring the formation of carbonyl-groups in the protein, detected by reduction with tritiated Na BH{sub 4}. The incubation of BSA with IP (50-500{mu}M), in the presence of 100{mu}M Cu{sup 2+} leaded to an increased and dose dependent {sup 3} H-incorporation by the oxidized protein. The production of oxidative damage by IP/Cu{sup 2+} was accompanied by marked BSA fragmentation, detected by SDS-polyacrylamide gel dependent (25-400{mu}M IP) des appearance of the original BSA band and appearance of smaller fragments spread in the gel, when incubation has been done in the presence of 100{mu}M Cu{sup 2+}. These results suggest that copper-catalysed oxidative degradation of proteins induced by catecholamines might be critically involved in the toxic action of these molecules

  15. Novel insights in the molecular pathogenesis of human copper homeostasis disorders through studies of protein-protein interactions

    NARCIS (Netherlands)

    Bie, P. de

    2007-01-01

    Copper is an essential element for living organisms, yet it is very toxic when present in amounts exceeding cellular needs. Delicate mechanisms have evolved to ensure proper copper homeostasis is maintained for the organism, as well as at a cellular level, and perturbations in these mechanisms give

  16. Transcriptomics as a tool to dissect copper homeostasis and COMMD protein function

    NARCIS (Netherlands)

    Müller, P.A.J.

    2008-01-01

    Gene expression profiling offers the possibility to objectively screen the complete genome for variations in gene expression in many different organisms in various defined environments. In the present work we aimed to gain novel insights in copper metabolism and in the function of COMMD (copper meta

  17. A molecular movie at 1.8 A resolution displays the photocycle of photoactive yellow protein, a eubacterial blue-light receptor, from nanoseconds to seconds.

    NARCIS (Netherlands)

    Ren, Z.; Perman, B.; Srajer, V.; Teng, T.Y.; Pradervand, C.; Bourgeois, D.; Schotte, F.; Ursby, T.; Kort, R.

    2001-01-01

    The photocycle of the bacterial blue-light photoreceptor, photoactive yellow protein, was stimulated by illumination of single crystals by a 7 ns laser pulse. The molecular events were recorded at high resolution by time-resolved X-ray Laue diffraction as they evolved in real time, from 1 ns to seco

  18. The Cellular Prion Protein Prevents Copper-Induced Inhibition of P2X4 Receptors

    Science.gov (United States)

    Lorca, Ramón A.; Varela-Nallar, Lorena; Inestrosa, Nibaldo C.; Huidobro-Toro, J. Pablo

    2011-01-01

    Although the physiological function of the cellular prion protein (PrPC) remains unknown, several evidences support the notion of its role in copper homeostasis. PrPC binds Cu2+ through a domain composed by four to five repeats of eight amino acids. Previously, we have shown that the perfusion of this domain prevents and reverses the inhibition by Cu2+ of the adenosine triphosphate (ATP)-evoked currents in the P2X4 receptor subtype, highlighting a modulatory role for PrPC in synaptic transmission through regulation of Cu2+ levels. Here, we study the effect of full-length PrPC in Cu2+ inhibition of P2X4 receptor when both are coexpressed. PrPC expression does not significantly change the ATP concentration-response curve in oocytes expressing P2X4 receptors. However, the presence of PrPC reduces the inhibition by Cu2+ of the ATP-elicited currents in these oocytes, confirming our previous observations with the Cu2+ binding domain. Thus, our observations suggest a role for PrPC in modulating synaptic activity through binding of extracellular Cu2+. PMID:22114745

  19. The Cellular Prion Protein Prevents Copper-Induced Inhibition of P2X4 Receptors

    Directory of Open Access Journals (Sweden)

    Ramón A. Lorca

    2011-01-01

    Full Text Available Although the physiological function of the cellular prion protein (PrPC remains unknown, several evidences support the notion of its role in copper homeostasis. PrPC binds Cu2+ through a domain composed by four to five repeats of eight amino acids. Previously, we have shown that the perfusion of this domain prevents and reverses the inhibition by Cu2+ of the adenosine triphosphate (ATP-evoked currents in the P2X4 receptor subtype, highlighting a modulatory role for PrPC in synaptic transmission through regulation of Cu2+ levels. Here, we study the effect of full-length PrPC in Cu2+ inhibition of P2X4 receptor when both are coexpressed. PrPC expression does not significantly change the ATP concentration-response curve in oocytes expressing P2X4 receptors. However, the presence of PrPC reduces the inhibition by Cu2+ of the ATP-elicited currents in these oocytes, confirming our previous observations with the Cu2+ binding domain. Thus, our observations suggest a role for PrPC in modulating synaptic activity through binding of extracellular Cu2+.

  20. Comparison of LECO FP-228 "nitrogen determinator" with AOAC copper catalyst Kjeldahl method for crude protein.

    Science.gov (United States)

    Sweeney, R A; Rexroad, P R

    1987-01-01

    The LECO FP-228 "Nitrogen Determinator" was compared with the AOAC copper catalyst Kjeldahl method, 7.033-7.037, for the determination of crude protein in feed materials. The completely microprocessor-controlled instrument determines nitrogen by measuring the nitrogen gas following combustion of the sample; it was easy to operate and broadly applicable. A wide variety of feed materials of various nitrogen levels were analyzed in one mixed sequence. Results were precise, accurate, and rapid. Analysis time for one sample was approximately 3 min. Fourteen samples containing 2.5-15.5% N were selected for study and consisted of meals, grains, forages, and standard organic materials. The overall mean for the 14 samples by the LECO combustion method was 8.61% N compared with an overall mean of 8.58% N for the AOAC Kjeldahl method. Within-sample standard deviations for the LECO combustion method ranged from 0.013 to 0.052% N with a pooled standard deviation (SD) of 0.033% N for the 14 samples. Standard deviations for the AOAC Kjeldahl method ranged from 0.006 to 0.035% N with a pooled SD of 0.022% N. Combined average recovery of nitrogen from tryptophan, lysine-HCl, and EDTA determined by the LECO combustion method was 99.94% compared to 99.88% determined by the AOAC Kjeldahl method.

  1. Photodynamics of blue-light-regulated phosphodiesterase BlrP1 protein from Klebsiella pneumoniae and its photoreceptor BLUF domain

    Energy Technology Data Exchange (ETDEWEB)

    Tyagi, A. [Institut II - Experimentelle und Angewandte Physik, Universitaet Regensburg, Universitaetstrasse 31, D-93053 Regensburg (Germany); Penzkofer, A. [Institut II - Experimentelle und Angewandte Physik, Universitaet Regensburg, Universitaetstrasse 31, D-93053 Regensburg (Germany)], E-mail: alfons.penzkofer@physik.uni-regensburg.de; Griese, J.; Schlichting, I. [Max-Planck-Institut fuer medizinische Forschung, Abteilung Biomolekulare Mechanismen, Jahnstrasse 29, D-69120 Heidelberg (Germany); Kirienko, Natalia V.; Gomelsky, Mark [Department of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071 (United States)

    2008-12-10

    The BlrP1 protein from the enteric bacterium Klebsiella pneumoniae consists of a BLUF and an EAL domain and may activate c-di-GMP phosphodiesterase by blue-light. The full-length protein, BlrP1, and its BLUF domain, BlrP1{sub B}LUF, are characterized by optical absorption and emission spectroscopy. The cofactor FAD in its oxidized redox state (FAD{sub ox}) is brought from the dark-adapted receptor state to the 10-nm red-shifted putative signalling state by violet light exposure. The recovery to the receptor state occurs with a time constant of about 1 min. The quantum yield of signalling state formation is about 0.17 for BlrP1{sub B}LUF and about 0.08 for BlrP1. The fluorescence efficiency of the FAD{sub ox} cofactor is small due to photo-induced reductive electron transfer. Prolonged light exposure converts FAD{sub ox} in the signalling state to the fully reduced hydroquinone form FAD{sub red}H{sup -} and causes low-efficient chromophore release with subsequent photo-degradation. The photo-cycle and photo-reduction dynamics in the receptor state and in the signalling state are discussed.

  2. Photodynamics of blue-light-regulated phosphodiesterase BlrP1 protein from Klebsiella pneumoniae and its photoreceptor BLUF domain

    Science.gov (United States)

    Tyagi, A.; Penzkofer, A.; Griese, J.; Schlichting, I.; Kirienko, Natalia V.; Gomelsky, Mark

    2008-12-01

    The BlrP1 protein from the enteric bacterium Klebsiella pneumoniae consists of a BLUF and an EAL domain and may activate c-di-GMP phosphodiesterase by blue-light. The full-length protein, BlrP1, and its BLUF domain, BlrP1_BLUF, are characterized by optical absorption and emission spectroscopy. The cofactor FAD in its oxidized redox state (FAD ox) is brought from the dark-adapted receptor state to the 10-nm red-shifted putative signalling state by violet light exposure. The recovery to the receptor state occurs with a time constant of about 1 min. The quantum yield of signalling state formation is about 0.17 for BlrP1_BLUF and about 0.08 for BlrP1. The fluorescence efficiency of the FAD ox cofactor is small due to photo-induced reductive electron transfer. Prolonged light exposure converts FAD ox in the signalling state to the fully reduced hydroquinone form FAD redH - and causes low-efficient chromophore release with subsequent photo-degradation. The photo-cycle and photo-reduction dynamics in the receptor state and in the signalling state are discussed.

  3. Copper modulates zinc metalloproteinase-dependent ectodomain shedding of key signaling and adhesion proteins and promotes the invasion of prostate cancer epithelial cells.

    Science.gov (United States)

    Parr-Sturgess, Catherine A; Tinker, Claire L; Hart, Claire A; Brown, Michael D; Clarke, Noel W; Parkin, Edward T

    2012-10-01

    A disintegrin and metalloproteinases (ADAMs) and matrix metalloproteinases (MMPs) are zinc metalloproteinases (ZMPs) that catalyze the "ectodomain shedding" of a range of cell surface proteins including signaling and adhesion molecules. These "sheddases" are associated with the invasion and metastasis of a range of cancers. Increased serum and tumor tissue levels of copper are also observed in several cancers, although little is known about how the metal might promote disease progression at the molecular level. In the current study, we investigated whether copper might regulate the ectodomain shedding of two key cell surface proteins implicated in the invasion and metastasis of prostate cancer, the Notch ligand Jagged1 and the adhesion molecule E-cadherin, and whether the metal was able to influence the invasion of the prostate cancer epithelial cell line PC3. Physiological copper concentrations stimulated the ZMP-mediated proteolysis of Jagged1 and E-cadherin in cell culture models, whereas other divalent metals had no effect. Copper-mediated Jagged1 proteolysis was also observed following the pretreatment of cells with cycloheximide and in a cell-free membrane system, indicating a posttranslational mechanism of sheddase activation. Finally, the concentrations of copper that stimulated ZMP-mediated protein shedding also enhanced PC3 invasion; an effect that could be negated using a sheddase inhibitor or copper chelators. Collectively, these data implicate copper as an important factor in promoting prostate cancer cell invasion and indicate that the selective posttranslational activation of ZMP-mediated protein shedding might play a role in this process.

  4. Hidden photoinduced reactivity of the blue fluorescent protein mKalama1

    DEFF Research Database (Denmark)

    Vegh, Russell B.; Bloch, Dmitry A.; Bommarius, Andreas S.

    2015-01-01

    absorption signal has a complex nature and spans the whole microsecond-to-second time scale. The mechanisms underlying the relaxation kinetics are disclosed based on the X-ray structural analysis of mKalama1 and the high-level electronic structure calculations of proposed intermediates in the photocycle. We...... of the chromophore radical cation to bulk solvent through a novel water-mediated proton-wire pathway. Our findings open up new perspectives on the dynamics of fluorescent proteins as tracked by its optical transient absorption in the time domain extending up to seconds....

  5. Different blue-light requirement for the accumulation of transcripts from nuclear genes for thylakoid proteins in Nicotiana tabacum and Lycopersicon esculentum.

    Science.gov (United States)

    Palomares, R; Herrmann, R G; Oelmüller, R

    1991-11-01

    We have isolated recombinant lambda gt11 phages which carry cDNA clones for the major light-harvesting chlorophyll a/b-binding proteins of photosystem I (LHCPI) and II (LHCPII), subunit II of photosystem I, a chlorophyll a/b-binding protein of photosystem II (CP24), the Rieske iron-sulphur protein of the cytochrome b6/f complex, and the 33, 23 and 16 kDa proteins of the water-oxidizing complex of photosystem II from Nicotiana tabacum. The nucleotide sequences of cDNA clones encoding the precursors for LHCPI and the FeS protein are presented. If tobacco or tomato seedlings, or seedlings of a phytochrome-deficient aurea mutant of tomato which lacks more than 95% of the phytochrome of the isogenic wild type, are kept in blue light, the transcript level of each of these genes is higher than in seedlings grown in red light suggesting the involvement of a blue-UVA-light photoreceptor. In the case of LHCPI, a 1 min blue-light pulse applied to red-light-grown seedlings is sufficient to increase the transcript levels to those present in blue-light-grown seedlings, whereas almost no increase is observed for transcripts encoding the FeS and 33 kDa proteins. If dark-grown tomato seedlings receive a single far-red-light pulse, significant stimulation is detected for LHCPI transcripts, whereas transcripts encoding the FeS and 33 kDa proteins are not stimulated. It is concluded that the lower light requirement for the increase in the LHCPI transcript level is not specific for one of the light-dependent signal transduction chains.

  6. Spectrophotometric total protein assay with copper(II)-neocuproine reagent in alkaline medium.

    Science.gov (United States)

    Sözgen, Kevser; Cekic, Sema Demirci; Tütem, Esma; Apak, Resat

    2006-02-28

    Total protein assay was made using copper(II)-neocuproine (Nc) reagent in alkaline medium (with the help of a hydroxide-carbonate-tartarate solution) after 30min incubation at 40 degrees C. The absorbance of the reduction product, Cu(I)-Nc complex, was recorded at 450nm against a reagent blank. The absorptivity of the developed method for bovine serum albumin (BSA) was 0.023lmg(-1)cm(-1), greater than that of Lowry assay (0.0098), and much greater than that of Cu(II)-bicinchoninic acid (BCA) assay (0.00077). The linear range of the developed method (8-100mgl(-1) BSA) was as wide as that of Lowry, and much wider than that of BCA (200-1000mgl(-1) BSA) assay. The sensitivity of the method was greater than those of Cu-based assays (biuret, Lowry, and BCA) with a LOD of 1mgl(-1) BSA. The within-run and between-run precisions as RSD were 0.73 and 1.01%, respectively. The selectivity of the proposed method for protein was much higher than those of dye-binding and Lowry assays: Most common interferents to other protein assays such as tris, ethanolamine, deoxycholate, CsCl, citrate, and triton X-100 were tolerated at 100-fold concentrations in the analysis of 10mgl(-1) BSA, while the tolerance limits for other interferents, e.g., (NH(4))(2)SO(4) and acetylsalicylic acid (50-fold), SDS (25-fold), and glycerol (20-fold) were at acceptable levels. The redox reaction of Cu(II)-Nc as an outer-sphere electron transfer agent with the peptide bond and with four amino acid residues (cystine, cysteine, tryptophan, and tyrosine) was kinetically more favourable than that of Cu(II) alone in the biuret assay. Since the reduction product of Cu(II) with protein, i.e., Cu(I), was coordinatively saturated with Nc in the stable Cu(Nc)(2)(+) chelate, re-oxidation of the formed Cu(I) with Fenton-like reactions was not possible, thereby preventing a loss of chromophore. After conventional protein extraction, precipitation, and redissolution procedures, the protein contents of the minced meat

  7. Probing the copper(II) binding features of angiogenin. Similarities and differences between a N-terminus peptide fragment and the recombinant human protein.

    Science.gov (United States)

    La Mendola, Diego; Farkas, Daniel; Bellia, Francesco; Magrì, Antonio; Travaglia, Alessio; Hansson, Örjan; Rizzarelli, Enrico

    2012-01-02

    The angiogenin protein (hAng) is a potent angiogenic factor and its cellular activities may be affected by copper ions even if it is yet unknown how this metal ion is able to produce this effect. Among the different regions of hAng potentially able to bind copper ions, the N-terminal domain appears to be an ideal candidate. Copper(II) complexes of the peptide fragments encompassing the amino acid residues 4-17 of hAng protein were characterized by potentiometric, UV-vis, CD, and EPR spectroscopic methods. The results show that these fragments have an unusual copper(II) binding ability. At physiological pH, the prevailing complex species formed by the peptide encompassing the protein sequence 4-17 is [CuHL], in which the metal ion is bound to two imidazole and two deprotonated amide nitrogen atoms disposed in a planar equatorial arrangement. Preliminary spectroscopic (UV-vis, CD, and EPR) data obtained on the copper(II) complexes formed by the whole recombinant hAng protein, show a great similarity with those obtained for the N-terminal peptide fragments. These findings indicate that within the N-terminal domain there is one of the preferred copper(II) ions anchoring site of the whole recombinant hAng protein.

  8. EFFECTS OF HIGHER LEVELS OF CHROMIUM AND COPPER ON SOME HAEMATOLOGICAL PARAMETERS AND SERUM PROTEINS IN BROILERS

    Directory of Open Access Journals (Sweden)

    M. Tariq Javed, F, Ahmad. N, Z, Rafique1 and M, Bashir

    2003-01-01

    Full Text Available Effects of higher levels of chromium alone and in combination with copper were investigated in broiler chicks divided into seven equal groups viz. A, B, C, D, E, F and G. Group G served as control receiving no treatment. Groups A, B and F received chromium chloride at the rate of 2 g/kg and nicotinic acid 150 mg/kg feed while C, D and F received chromium chloride 8 g/kg and nicotinic acid 150mg/kg. Broilers of groups A and C received copper sulfate at the rate of 200 mg/kg while groups Band D 400 mg/kg feed. Haematological parameters studied revealed non-significant difference between treatment groups and control in haemoglobin concentration and total erythrocyte counts. However, only at 4th week, lower PCV was observed in birds fed higher levels of chromium chloride alone. Increase in TLC was observed in birds fed low chromium alone or' with low levels of copper. Results of serum proteins including total protein, albumin and globulin during first three weeks showed significantly or relatively lower values in treatment groups than control. Serum globulins generally revealed non-significant difference between treatment groups and control.

  9. Intracellular localization of GBF proteins and blue light-induced import of GBF2 fusion proteins into the nucleus of cultured Arabidopsis and soybean cells.

    Science.gov (United States)

    Terzaghi, W B; Bertekap, R L; Cashmore, A R

    1997-05-01

    The G-box is an important regulatory element found in the promoters of many different genes. Four members of an Arabidopsis gene family encoding basic leucine zipper proteins (GBFs) which bind the G-box have previously been cloned. To study GBFs, a polyclonal antibody was raised against GBF1 expressed in bacteria. This antibody also recognized GBF2 and GBF3. Immunoblot analysis of nuclear and cytoplasmic fractions from Arabidopsis and soybean (SB-M) cell cultures indicated that over 90% of proteins detected with anti-GBF1 were cytoplasmic. Electrophoretic mobility shift assays indicated that over 90% of G-box binding activity was cytoplasmic. DNA affinity chromatography demonstrated that each protein detected with anti-GBF1 specifically bound the G-box. To study individual GBFs, DNA constructs fusing GBF1, GBF2 and GBF4 to GUS were made and assayed by transient expression in SB-M protoplasts. Of GUS:GBF1 proteins, 50-62% were localized in the cytoplasm under all conditions tested, while 97% of GUS:GBF4 was localized in the nucleus. By contrast, whereas about 50% of GUS:GBF2 was found in the cytoplasm of dark-grown cells, over 80% of this protein was found in the nucleus in cells cultured under blue light. Deletion analysis of GBF1 identified a region between amino acids 112 and 164 apparently required for cytoplasmic retention. These results suggest the intriguing possibility that limitation of nuclear access may be an important control on GBF activity. In particular, GBF2 is apparently specifically imported into the nucleus in response to light.

  10. Pressure-sensitive reaction yield of the TePixD blue-light sensor protein.

    Science.gov (United States)

    Kuroi, Kunisato; Okajima, Koji; Ikeuchi, Masahiko; Tokutomi, Satoru; Kamiyama, Tadashi; Terazima, Masahide

    2015-02-19

    The effect of pressure on the dissociation reaction of the TePixD decamer was investigated by high-pressure transient grating (TG). The TG signal intensity representing the dissociation reaction of the TePixD decamer significantly decreased by applying a relatively small pressure. On the other hand, the reaction rate increased with increasing pressure. The equilibrium between the pentamer and the decamer was investigated by high-pressure dynamic light scattering. The results indicated that the fraction of the decamer slightly increased in the high-pressure region. From these measurements, it was concluded that the pressure-dependent signal intensity originated from the decrease of the quantum yield of the dissociation reaction of the decamer, indicating that this reaction efficiency is very sensitive to pressure. Using densimetry at high pressures, the compressibility was found to be pressure dependent even in a relatively low pressure range. We attributed the origin of the pressure-sensitive reaction yield to the decrease of compressibility at high pressure. Because the compressibility is related to the volume fluctuation, this observation suggests that the driving force for this reaction is fluctuation of the protein. The relationship between the cavities at the interfaces of the monomer units and the reactivity is also discussed.

  11. Phosphorylation of amyloid precursor protein at threonine 668 is essential for its copper-responsive trafficking in SH-SY5Y neuroblastoma cells.

    Science.gov (United States)

    Acevedo, Karla M; Opazo, Carlos M; Norrish, David; Challis, Leesa M; Li, Qiao-Xin; White, Anthony R; Bush, Ashley I; Camakaris, James

    2014-04-18

    Amyloid precursor protein (APP) undergoes post-translational modification, including O- and N-glycosylation, ubiquitination, and phosphorylation as it traffics through the secretory pathway. We have previously reported that copper promotes a change in the cellular localization of APP. We now report that copper increases the phosphorylation of endogenous APP at threonine 668 (Thr-668) in SH-SY5Y neuronal cells. The level of APPT668-p (detected using a phospho-site-specific antibody) exhibited a copper-dependent increase. Using confocal microscopy imaging we demonstrate that the phospho-deficient mutant, Thr-668 to alanine (T668A), does not exhibit detectable copper-responsive APP trafficking. In contrast, mutating a serine to an alanine at residue 655 does not affect copper-responsive trafficking. We further investigated the importance of the Thr-668 residue in copper-responsive trafficking by treating SH-SY5Y cells with inhibitors for glycogen synthase kinase 3-β (GSK3β) and cyclin-dependent kinases (Cdk), the main kinases that phosphorylate APP at Thr-668 in neurons. Our results show that the GSK3β kinase inhibitors LiCl, SB 216763, and SB 415286 prevent copper-responsive APP trafficking. In contrast, the Cdk inhibitors Purvalanol A and B had no significant effect on copper-responsive trafficking in SH-SY5Y cells. In cultured primary hippocampal neurons, copper promoted APP re-localization to the axon, and this effect was inhibited by the addition of LiCl, indicating that a lithium-sensitive kinase(s) is involved in copper-responsive trafficking in hippocampal neurons. This is consistent with APP axonal transport to the synapse, where APP is involved in a number of functions. We conclude that copper promotes APP trafficking by promoting a GSK3β-dependent phosphorylation in SH-SY5Y cells.

  12. Simultaneous removal of methylene blue and copper(II) ions by photoelectron catalytic oxidation using stannic oxide modified iron(III) oxide composite electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Jinqiu [College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai' an, Shandong 271018 (China); Li, Xiaochen, E-mail: lixiaochen02@163.com [College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai' an, Shandong 271018 (China); Zheng, Hao [College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai' an, Shandong 271018 (China); Li, Peiqiang; Wang, Huying [College of Chemistry and Material Science, Shandong Agricultural University, Tai' an, Shandong 271018 (China)

    2015-08-15

    Highlights: • Photoelectron catalytic oxidation was used for methylene blue and Cu{sup 2+} removal. • SnO{sub 2}/Fe{sub 2}O{sub 3} was prepared and characterized for use as photoanodes and photocathodes. • Optimal reaction conditions were determined for methylene blue and Cu{sup 2+} removal. • Methylene blue removal followed the Langmuir–Freundlich–Hinshelwood kinetic model. • Cu{sup 2+} removal followed the first-order rate model. - Abstract: Stannic oxide modified Fe(III) oxide composite electrodes (SnO{sub 2}/Fe{sub 2}O{sub 3}) were synthesized for simultaneously removing methylene blue (MB) and Cu(II) from wastewater using photoelectron catalytic oxidation (PEO). The SnO{sub 2}/Fe{sub 2}O{sub 3} electrodes were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and photoelectrochemical techniques. The removal of MB and Cu(II) by PEO using the SnO{sub 2}/Fe{sub 2}O{sub 3} composite electrodes was studied in terms of reaction time, electric current density, and pH of the electrolyte. The kinetics of the reactions were investigated using batch assays. The optimal reaction time, pH, and electric current density of the PEO process were determined to be 30 min, 6.0, and 10 mA/cm{sup 2}, respectively. The removal rates of MB from wastewater treated by PEO and electron catalytic oxidation process were 84.87% and 70.64%, respectively, while the recovery rates of Cu(II) were 91.75% and 96.78%, respectively. The results suggest that PEO is an effective method for the simultaneous removal of MB and Cu(II) from wastewater, and the PEO process exhibits a much higher removal rate for MB and Cu(II) compared to the electron catalytic oxidation process. Furthermore, the removal of MB was found to follow the Langmuir–Freundlich–Hinshelwood kinetic model, whereas the removal of Cu(II) fitted well to the first-order reaction model.

  13. Stabilization of native amyloid β-protein oligomers by Copper and Hydrogen peroxide Induced Cross-linking of Unmodified Proteins (CHICUP).

    Science.gov (United States)

    Williams, Thomas L; Serpell, Louise C; Urbanc, Brigita

    2016-03-01

    Oligomeric assemblies are postulated to be proximate neurotoxic species in human diseases associated with aberrant protein aggregation. Their heterogeneous and transient nature makes their structural characterization difficult. Size distributions of oligomers of several amyloidogenic proteins, including amyloid β-protein (Aβ) relevant to Alzheimer's disease (AD), have been previously characterized in vitro by photo-induced cross-linking of unmodified proteins (PICUP) followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Due to non-physiological conditions associated with the PICUP chemistry, Aβ oligomers cross-linked by PICUP may not be representative of in vivo conditions. Here, we examine an alternative Copper and Hydrogen peroxide Induced Cross-linking of Unmodified Proteins (CHICUP), which utilizes naturally occurring divalent copper ions and hydrogen peroxide and does not require photo activation. Our results demonstrate that CHICUP and PICUP applied to the two predominant Aβ alloforms, Aβ40 and Aβ42, result in similar oligomer size distributions. Thioflavin T fluorescence data and atomic force microscopy images demonstrate that both CHICUP and PICUP stabilize Aβ oligomers and attenuate fibril formation. Relative to noncross-linked peptides, CHICUP-treated Aβ40 and Aβ42 cause prolonged disruption to biomimetic lipid vesicles. CHICUP-stabilized Aβ oligomers link the amyloid cascade, metal, and oxidative stress hypotheses of AD into a more comprehensive understanding of the molecular basis of AD pathology. Because copper and hydrogen peroxide are elevated in the AD brain, CHICUP-stabilized Aβ oligomers are biologically relevant and should be further explored as a new therapeutic target.

  14. Posttranslational regulation of copper transporters

    NARCIS (Netherlands)

    van den Berghe, P.V.E.

    2009-01-01

    The transition metal copper is an essential cofactor for many redox-active enzymes, but excessive copper can generate toxic reactive oxygen species. Copper homeostasis is maintained by highly conserved proteins, to balance copper uptake, distribution and export on the systemic and cellular level. Th

  15. Copper(II) complexes of prion protein PEG11-tetraoctarepeat fragment: spectroscopic and voltammetric studies.

    Science.gov (United States)

    Bonomo, Raffaele P; Di Natale, Giuseppe; Rizzarelli, Enrico; Tabbì, Giovanni; Vagliasindi, Laura I

    2009-04-14

    Spectroscopic (UV-Vis and EPR) and voltammetric studies have been carried out on the copper(II) complexes with the Ac-PEG11-(PHGGGWGQ)4-NH2 (L) polypeptide. In the ratios Cu : L 3 : 1 and 4 : 1, the two [Cu3(L)H(-6)] and [Cu4(L)H(-8)] complex species have been characterized at neutral pH values. All the copper atoms occupy similar coordination sites formed by imidazole, peptidic nitrogen atoms and carbonyl oxygen atoms in a square base pyramidal geometry. Voltammetric measurements on these systems point out the cooperativity in the electron transfer processes among the copper(II) sites during their reduction. NO interaction with these polynuclear copper species is characterized by the reduction of the copper sites through the formation of two different intermediate complex species. When an excess of the Ac-PEG11-(PHGGGWGQ)4-NH2 ligand is considered, frozen solution EPR parameters and UV-Vis spectroscopic data identify the [Cu(N(im))4]2+ chromophore, which does not interact with NO.

  16. Accesses to electronic structures and the excited states of blue luminescent copper(I) complexes containing N-heterocyclic carbene ligands: a DFT/TDDFT exploitation.

    Science.gov (United States)

    Li, Qiang; Zhao, Feng; Xu, Shengxian; Xia, Hongying; Wang, Jinglan; Wang, Yibo

    2014-09-01

    The ground electronic states and photophysical properties of three designed Cu(I) complexes [Cu(ImNHC)(POP)](+) (1), [Cu(methyl-ImNHC)(POP)](+) (2), and [Cu(BenzImNHC)(POP)](+) (3); where [ImNHC = 3-methyl-1-(pyridin-2-yl)-1H-imidazol-2-ylidene; methyl-ImNHC = 3-methyl-1-(pyridin-2-ylmethyl)-1H-imidazol-2-ylidene; BenzImNHC = 3-methyl-1-(pyridin-2-yl)-1H-benzimidazol-2-ylidene], have been investigated using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The results reveal that the presence of the methylene spacer in the NHC ligands has a more direct effect on the distribution of frontier molecular orbitals while the elongation of π conjugation provided by the fused imidazole in the NHC ligands has a negligible effect. The UV-vis absorption spectra of all the complexes are well produced by TD-DFT calculations based on the charge transfer amount calculations and the corresponding band assignments are discussed. Importantly, the triplet energy calculations demonstrated that complex 2 would be a highly efficient blue emitter with the deep-blue of 440 nm.

  17. Insight into Bio-metal Interface Formation in vacuo: Interplay of S-layer Protein with Copper and Iron

    Science.gov (United States)

    Makarova, Anna A.; Grachova, Elena V.; Neudachina, Vera S.; Yashina, Lada V.; Blüher, Anja; Molodtsov, Serguei L.; Mertig, Michael; Ehrlich, Hermann; Adamchuk, Vera K.; Laubschat, Clemens; Vyalikh, Denis V.

    2015-03-01

    The mechanisms of interaction between inorganic matter and biomolecules, as well as properties of resulting hybrids, are receiving growing interest due to the rapidly developing field of bionanotechnology. The majority of potential applications for metal-biohybrid structures require stability of these systems under vacuum conditions, where their chemistry is elusive, and may differ dramatically from the interaction between biomolecules and metal ions in vivo. Here we report for the first time a photoemission and X-ray absorption study of the formation of a hybrid metal-protein system, tracing step-by-step the chemical interactions between the protein and metals (Cu and Fe) in vacuo. Our experiments reveal stabilization of the enol form of peptide bonds as the result of protein-metal interactions for both metals. The resulting complex with copper appears to be rather stable. In contrast, the system with iron decomposes to form inorganic species like oxide, carbide, nitride, and cyanide.

  18. Investigation of iron metabolism in mice expressing a mutant Menke's copper transporting ATPase (Atp7a protein with diminished activity (Brindled; Mo (Br (/y .

    Directory of Open Access Journals (Sweden)

    Sukru Gulec

    Full Text Available During iron deficiency, perturbations in copper homeostasis have frequently been documented. Previous studies in iron-deprived rats demonstrated that enterocyte and hepatic copper levels increase and a copper transporter (the Menkes Copper ATPase; Atp7a is induced in the duodenal epithelium in parallel to iron transport-related genes (e.g. Dmt1, Dcytb, Fpn1. Moreover, two ferroxidase proteins involved in iron homeostasis, hephaestin expressed in enterocytes and ceruloplasmin, produced and secreted into blood by the liver, are copper-dependent enzymes. We thus aimed to test the hypothesis that Atp7a function is important for the copper-related compensatory response of the intestinal epithelium to iron deficiency. Accordingly, iron homeostasis was studied for the first time in mice expressing a mutant Atp7a protein with minimal activity (Brindled [Mo (Br (/y ]. Mutant mice were rescued by perinatal copper injections, and, after a 7-8 week recovery period, were deprived of dietary iron for 3 weeks (along with WT littermates. Adult Mo (Br (/y mice displayed copper-deficiency anemia but had normal iron status; in contrast, iron-deprived Mo (Br (/y mice were iron deficient and more severely anemic with partial amelioration of the copper-deficient phenotype. Intestinal iron absorption in both genotypes (WT and Mo (Br (/y increased ∼3-fold when mice consumed a low-iron diet and ∼6-fold when mice were concurrently bled. WT mice exhibited no alterations in copper homeostasis in response to iron deprivation or phlebotomy. Conversely, upregulation of iron absorption was associated with increased enterocyte and liver copper levels and serum ferroxidase (ceruloplasmin activity in Mo (Br (/y mice, typifying the response to iron deprivation in many mammalian species. We thus speculate that a copper threshold exists that is necessary to allow appropriate regulate of iron absorption. In summary, Mo (Br (/y mice were able to adequately regulate iron absorption

  19. Ultrasensitive electrochemical detection of protein tyrosine kinase-7 by gold nanoparticles and methylene blue assisted signal amplification.

    Science.gov (United States)

    Miao, Xiangmin; Li, Zongbing; Zhu, Aihua; Feng, Zhaozhong; Tian, Jun; Peng, Xue

    2016-09-15

    We present here an ultrasensitive and simple strategy for protein tyrosine kinase-7 (PTK7) detection based on the recognition-induced structure change of sgc8 aptamer, and the signal change of methylene blue (MB) that interacted with sandwiched DNA complex. To construct such a sensor, an homogeneous nano-surface was formed firstly on the glass carbon electrode (GCE) by using negatively charged Nafion (Nf) as the inner layer and positively charged gold nanoparticles ((+)AuNPs) as the outer layer, followed by the immobilization of sgc8 aptamer based on Au-S bond. In the presence of helper probe (HP), sandwiched DNA complex was formed between the sgc8 aptamer and the DNA modified gold nanoparticle probe (DNA-AuNPs). Then, a strong current signal was produced due to the capture of abundant MB molecules by both the sandwiched DNA complex and the multiple DNAs that modified on AuNPs surface. However, the specific binding of sgc8 aptamer with PNK7 would trigger a structure transition of it, and directly prevented the following formation of sandwiched structure and the capture of MB. Thus, PTK7 detection could be realized based on monitoring the signal reduction of MB upon incubation of sgc8 aptamer with PTK7. Under optimal conditions, a low detection limit of 372 fM was obtained for PNK7 detection. Due to the employment of sgc8 aptamer, the proposed biosensor exhibited high selectivity to PNK7. Moreover, satisfactory results were obtained when the proposed method was applied for PNK7 detection in cellular debris.

  20. $^{111m}$Cd- and $^{199m}$Hg-derivatives of blue oxidases

    CERN Multimedia

    2002-01-01

    The rack-induced bonding concept (H.B.Gray & B.G.~Malmstroem, Comments Inorg. Chem, 2, 203, 1983) postulates that the bound metal ion in metalloproteins is forced to adopt a coordination geometry determined by the rigid peptide conformation of the protein. Alternatively, the metal ion could create its own favoured coordination geometry in a soft peptide conformation. In order to decide who is slave or master the changes of coordination and rigidity of metal sites in blue copper proteins due to metal and ligand exchange were studied by $^{111m}$Cd and $^{199m}$Hg $\\gamma$-$\\gamma$-perturbed angular correlation (PAC). To get a better understanding of the so called " Type 1 Copper Site " of the blue oxidases laccase (LAC) and ascorbate oxidase (AO) we concentrated our investigations on the small blue copper proteins azurin and plastocyanin. \\\\ \\\\In azurin~(Az), the metal ligand methionine 121~(M121) was replaced by several amino acids, e.g. asparagine~(N), glutamic acid~(E), via site directed mutagenesis. Di...

  1. Reclamation with blue-green algae: changes in nucleic acids, protein and nitrogen content of algae exposed to solid waste of a chlor-alkali factory

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, B.B.; Nanda, D.R.; Misra, B.N.

    1985-01-01

    During an attempt at the possible reclamation of solid waste from a chlor-alkali factory by blue-green algae, the effects of the solid waste on biochemical variables were studied. DNA, RNA, protein, and algal nitrogen content of the algal material showed a significant decrease with increase in time and also solid waste concentration. An increase in RNA/DNA ratio and a decrease in protein/RNA ratio were also observed. Algae accumulated appreciable amounts of mercury from the waste, showing dependence on both concentration and time. Significant correlations were obtained between mercury uptake and concentrations of the waste and between different combinations of algae and mercury uptake.

  2. Mung bean trypsin inhibitor is effective in suppressing the degradation of myofibrillar proteins in the skeletal muscle of blue scad (Decapterus maruadsi).

    Science.gov (United States)

    Sun, Le-Chang; Yoshida, Asami; Cai, Qiu-Feng; Liu, Guang-Ming; Weng, Ling; Tachibana, Katsuyasu; Su, Wen-Jin; Cao, Min-Jie

    2010-12-22

    Mung bean trypsin inhibitor (MBTI) of the Bowman-Birk family was purified to homogeneity with a molecular mass of approximately 9 kDa on tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and 8887.25 Da as determined by matrix-assisted laser desorption/ionization-quadrupole ion trap-time-of-flight mass spectrometry (MALDI-QIT-TOF MS). Using blue scad myofibrillar proteins as targets, it was found that, in the absence of MBTI, proteolysis of myofibrillar proteins, especially myosin heavy chain (MHC), could be identified after incubation at 55 °C for 2 h, while in the presence of MBTI, with a final concentration of 25 ng/mL, proteolysis of these proteins was greatly suppressed even after incubation for 3 h. Although cysteine proteinase inhibitor E-64 was also effective in preventing protein degradation, inhibitors for metallo- and asparatic proteinases did not reveal obvious inhibitory effects. Our present results strongly suggested that the naturally occurring legume bean seed protein MBTI can be used as an effective additive in preventing marine fish blue scad surimi gel softening, which is quite possibly caused by myofibril-bound serine proteinase (MBSP).

  3. Critical roles for the COOH terminus of the Cu-ATPase ATP7B in protein stability, trans-Golgi network retention, copper sensing, and retrograde trafficking.

    Science.gov (United States)

    Braiterman, L; Nyasae, L; Leves, F; Hubbard, A L

    2011-07-01

    ATP7A and ATP7B are copper-transporting P-type ATPases that are essential to eukaryotic copper homeostasis and must traffic between intracellular compartments to carry out their functions. Previously, we identified a nine-amino acid sequence (F37-E45) in the NH(2) terminus of ATP7B that is required to retain the protein in the Golgi when copper levels are low and target it apically in polarized hepatic cells when copper levels rise. To understand further the mechanisms regulating the intracellular dynamics of ATP7B, using multiple functional assays, we characterized the protein phenotypes of 10 engineered and Wilson disease-associated mutations in the ATP7B COOH terminus in polarized hepatic cells and fibroblasts. We also examined the behavior of a chimera between ATP7B and ATP7A. Our results clearly demonstrate the importance of the COOH terminus of ATP7B in the protein's copper-responsive apical trafficking. L1373 at the end of transmembrane domain 8 is required for protein stability and Golgi retention in low copper, the trileucine motif (L1454-L1456) is required for retrograde trafficking, and the COOH terminus of ATP7B exhibits a higher sensitivity to copper than does ATP7A. Importantly, our results demonstrating that four Wilson disease-associated missense mutations behaved in a wild-type manner in all our assays, together with current information in the literature, raise the possibility that several may not be disease-causing mutations.

  4. Serine-selective aerobic cleavage of peptides and a protein using a water-soluble copper-organoradical conjugate.

    Science.gov (United States)

    Seki, Yohei; Tanabe, Kana; Sasaki, Daisuke; Sohma, Youhei; Oisaki, Kounosuke; Kanai, Motomu

    2014-06-16

    The site-specific cleavage of peptide bonds is an important chemical modification of biologically relevant macromolecules. The reaction is not only used for routine structural determination of peptides, but is also a potential artificial modulator of protein function. Realizing the substrate scope beyond the conventional chemical or enzymatic cleavage of peptide bonds is, however, a formidable challenge. Here we report a serine-selective peptide-cleavage protocol that proceeds at room temperature and near neutral pH value, through mild aerobic oxidation promoted by a water-soluble copper-organoradical conjugate. The method is applicable to the site-selective cleavage of polypeptides that possess various functional groups. Peptides comprising D-amino acids or sensitive disulfide pairs are competent substrates. The system is extendable to the site-selective cleavage of a native protein, ubiquitin, which comprises more than 70 amino acid residues.

  5. Kind of Blue - Europa Blues

    DEFF Research Database (Denmark)

    Mortensen, Tore; Kirkegaard, Peter

    2009-01-01

    Bidraget reflekterer over sammenhænge mellem to værker fra det musikalske og litterære område. Det drejer sig om Miles Davis' Kind of Blue fra 1959 og Arne Dahls krimi, Europa Blues fra 2001. Den grundlæggende indfaldsvinkel er det performative, den frie, men samtidigt disciplinerede musikalske...

  6. Ways and means of coping with uncertainties of the relationship of the genetic blue print to protein structure and function in the cell

    Directory of Open Access Journals (Sweden)

    Helmreich Ernst JM

    2010-09-01

    Full Text Available Abstract As one of the disciplines of systems biology, proteomics is central to enabling the elucidation of protein function within the cell; furthermore, the question of how to deduce protein structure and function from the genetic readout has gained new significance. This problem is of particular relevance for proteins engaged in cell signalling. In dealing with this question, I shall critically comment on the reliability and predictability of transmission and translation of the genetic blue print into the phenotype, the protein. Based on this information, I will then evaluate the intentions and goals of today's proteomics and gene-networking and appraise their chances of success. Some of the themes commented on in this publication are explored in greater detail with particular emphasis on the historical roots of concepts and techniques in my forthcoming book, published in German: Von Molekülen zu Zellen. 100 Jahre experimentelle Biologie. Betrachtungen eines Biochemikers.

  7. [Copper pathology (author's transl)].

    Science.gov (United States)

    Mallet, B; Romette, J; Di Costanzo, J D

    1982-01-30

    Copper is an essential dietary component, being the coenzyme of many enzymes with oxidase activity, e.g. ceruloplasmin, superoxide dismutase, monoamine oxidase, etc. The metabolism of copper is complex and imperfectly known. Active transport of copper through the intestinal epithelial cells involves metallothionein, a protein rich in sulfhydryl groups which also binds the copper in excess and probably prevents absorption in toxic amounts. In hepatocytes a metallothionein facilitates absorption by a similar mechanism and regulates copper distribution in the liver: incorporation in an apoceruloplasmin, storage and synthesis of copper-dependent enzymes. Metallothioneins and ceruloplasmin are essential to adequate copper homeostasis. Apart from genetic disorders, diseases involving copper usually result from hypercupraemia of varied origin. Wilson's disease and Menkes' disease, although clinically and pathogenetically different, are both marked by low ceruloplasmin and copper serum levels. The excessive liver retention of copper in Wilson's disease might be due to increased avidity of hepatic metallothioneins for copper and decreased biliary excretion through lysosomal dysfunction. Menkes' disease might be due to low avidity of intestinal and hepatic metallothioneins for copper. The basic biochemical defect responsible for these two hereditary conditions has not yet been fully elucidated.

  8. Biophysical and morphological studies on the dual interaction of non-octarepeat prion protein peptides with copper and nucleic acids.

    Science.gov (United States)

    Chaves, Juliana A P; Sanchez-López, Carolina; Gomes, Mariana P B; Sisnande, Tháyna; Macedo, Bruno; de Oliveira, Vanessa End; Braga, Carolina A C; Rangel, Luciana P; Silva, Jerson L; Quintanar, Liliana; Cordeiro, Yraima

    2014-08-01

    Conversion of prion protein (PrP) to an altered conformer, the scrapie PrP (PrP(Sc)), is a critical step in the development of transmissible spongiform encephalopathies. Both Cu(II) and nucleic acid molecules have been implicated in this conversion. Full-length PrP can bind up to six copper ions; four Cu(II) binding sites are located in the octarepeat domain (residues 60-91), and His-96 and His-111 coordinate two additional copper ions. Experimental evidence shows that PrP binds different molecules, resulting in diverse cellular signaling events. However, there is little information about the interaction of macromolecular ligands with Cu(II)-bound PrP. Both RNA and DNA sequences can bind PrP, and this interaction results in reciprocal conformational changes. Here, we investigated the interaction of Cu(II) and nucleic acids with amyloidogenic non-octarepeat PrP peptide models (comprising human PrP residues 106-126 and hamster PrP residues 109-149) that retain His-111 as the copper-anchoring residue. The effect of Cu(II) and DNA or RNA sequences in the aggregation, conformation, and toxicity of PrP domains was investigated at low and neutral pH. Circular dichroism and EPR spectroscopy data indicate that interaction of the PrP peptides with Cu(II) and DNA occurs at pH 7. This dual interaction induces conformational changes in the peptides, modulating their aggregation, and affecting the morphology of the aggregated species, resulting in different cytotoxic effects. These results provide new insights into the role of Cu(II) and nucleic acid sequences in the structural conversion and aggregation of PrP, which are both critical events related to prion pathogenesis.

  9. Blue Laser.

    Science.gov (United States)

    1985-12-01

    HOLLOW CATHODE LASER FABRICATION 13 4. EXPERIENCE WITH THE BLUE LASER 18 4.1 Operational and Processing Experience 18 4.2 Performance Testing 20 5...34 -. - . •. SECTION 3 BLUE HOLLOW CATHODE LASER FABRICATION This section presents an overview of the steps taken in creating a HCL. There is...to the laser assembly. These steps can actually be considered as the final steps in laser fabrication because some of them involve adding various

  10. Cobalt-Blue Decoration Painted on Early Islamic White Glazed Wares

    OpenAIRE

    波頭, 桂

    1998-01-01

    White glazed ware with cobalt-blue decoration and white glazed ware with cobalt-blue and copper-green decoration, produced in Mesopotamia during the Abbasid period, are objects of this paper. Sherds of these types

  11. Silencing of the Menkes copper-transporting ATPase (Atp7a) gene increases cyclin D1 protein expression and impairs proliferation of rat intestinal epithelial (IEC-6) cells.

    Science.gov (United States)

    Gulec, Sukru; Collins, James F

    2014-10-01

    The Menkes copper-transporting ATPase (Atp7a) has dual roles in mammalian enterocytes: pumping copper into the trans-Golgi network (to support cuproenzyme synthesis) and across the basolateral membrane (to deliver dietary copper to the blood). Atp7a is strongly induced in the rodent duodenum during iron deprivation, suggesting that copper influences iron homeostasis. To investigate this possibility, Atp7a was silenced in rat intestinal epithelial (IEC-6) cells. Irrespective of its influence on iron homeostasis, an unexpected observation was made in the Atp7a knockdown (KD) cells: the cells grew slower (∼40% fewer cells at 96h) and were larger than negative-control shRNA-transfected cells. Lack of Atp7a activity thus perturbed cell cycle control. To elucidate a possible molecular mechanism, expression of two important cell cycle control proteins was assessed. Cyclin D1 (CD1) protein expression increased in Atp7a KD cells whereas proliferating-cell nuclear antigen (PCNA) expression was unaltered. Increased CD1 expression is consistent with impaired cell cycle progression. Expression of additional cell proliferation marker genes (p21 and Ki67) was also investigated; p21 expression increased, whereas Ki67 decreased, both consistent with diminished cell growth. Further experiments were designed to determine whether increased cellular copper content was the trigger for the altered growth phenotype of the Atp7a KD cells. Copper loading, however, did not influence the expression patterns of CD1, p21 or Ki67. Overall, these findings demonstrate that Atp7a is required for normal proliferation of IEC-6 cells. How Atp7a influences cell growth is unclear, but the underlying mechanism could relate to its roles in intracellular copper distribution or cuproenzyme synthesis.

  12. Copper induction of enhanced green fluorescent protein expression in Pleurotus ostreatus driven by laccase poxa1b promoter.

    Science.gov (United States)

    Amore, Antonella; Honda, Yoichi; Faraco, Vincenza

    2012-12-01

    In silico analyses of several laccase promoter sequences have shown the presence of many different responsive elements differentially distributed along the promoter sequences. Analysis of Pleurotus ostreatus laccase promoter poxa1b extending around 1400-bp upstream of the start codon showed the presence of several putative response elements, such as 10 metal-responsive elements. Development of a system for in vivo analysis of P. ostreatus laccase promoter poxa1b by enhanced green fluorescent protein expression was carried out, based on a polyethylene glycol-mediated procedure for fungal transformation. Quantitative measurement of fluorescence expressed in P. ostreatus transformants grown in the presence and in the absence of copper sulfate was performed, demonstrating an increase in expression level induced by the metal.

  13. The Lys1010-Lys1325 fragment of the Wilson's disease protein binds nucleotides and interacts with the N-terminal domain of this protein in a copper-dependent manner.

    Science.gov (United States)

    Tsivkovskii, R; MacArthur, B C; Lutsenko, S

    2001-01-19

    Wilson's disease, an autosomal disorder associated with vast accumulation of copper in tissues, is caused by mutations in a gene encoding a copper-transporting ATPase (Wilson's disease protein, WNDP). Numerous mutations have been identified throughout the WNDP sequence, particularly in the Lys(1010)-Lys(1325) segment; however, the biochemical properties and molecular mechanism of WNDP remain poorly characterized. Here, the Lys(1010)-Lys(1325) fragment of WNDP was overexpressed, purified, and shown to form an independently folded ATP-binding domain (ATP-BD). ATP-BD binds the fluorescent ATP analogue trinitrophenyl-ATP with high affinity, and ATP competes with trinitrophenyl-ATP for the binding site; ADP and AMP appear to bind to ATP-BD at the site separate from ATP. Purified ATP-BD hydrolyzes ATP and interacts specifically with the N-terminal copper-binding domain of WNDP (N-WNDP). Strikingly, copper binding to N-WNDP diminishes these interactions, suggesting that the copper-dependent change in domain-domain contact may represent the mechanism of WNDP regulation. In agreement with this hypothesis, N-WNDP induces conformational changes in ATP-BD as evidenced by the altered nucleotide binding properties of ATP-BD in the presence of N-WNDP. Significantly, the effects of copper-free and copper-bound N-WNDP on ATP-BD are not identical. The implications of these results for the WNDP function are discussed.

  14. D-penicillamine prevents ram sperm agglutination by reducing the disulphide bonds of a copper-binding sperm protein.

    Science.gov (United States)

    Leahy, T; Rickard, J P; Aitken, R J; de Graaf, S P

    2016-05-01

    Head-to-head agglutination of ram spermatozoa is induced by dilution in the Tyrode's capacitation medium with albumin, lactate and pyruvate (TALP) and ameliorated by the addition of the thiol d-penicillamine (PEN). To better understand the association and disassociation of ram spermatozoa, we investigated the mechanism of action of PEN in perturbing sperm agglutination. PEN acts as a chelator of heavy metals, an antioxidant and a reducing agent. Chelation is not the main mechanism of action, as the broad-spectrum chelator ethylenediaminetetraacetic acid and the copper-specific chelator bathocuproinedisulfonic acid were inferior anti-agglutination agents compared with PEN. Oxidative stress is also an unlikely mechanism of sperm association, as PEN was significantly more effective in ameliorating agglutination than the antioxidants superoxide dismutase, ascorbic acid, α-tocopherol and catalase. Only the reducing agents cysteine and DL-dithiothreitol displayed similar levels of non-agglutinated spermatozoa at 0 h compared with PEN but were less effective after 3 h of incubation (37 °C). The addition of 10 µM Cu(2+) to 250 µM PEN + TALP caused a rapid reversion of the motile sperm population from a non-agglutinated state to an agglutinated state. Other heavy metals (cobalt, iron, manganese and zinc) did not provoke such a strong response. Together, these results indicate that PEN prevents sperm association by the reduction of disulphide bonds on a sperm membrane protein that binds copper. ADAM proteins are possible candidates, as targeted inhibition of the metalloproteinase domain significantly increased the percentage of motile, non-agglutinated spermatozoa (52.0% ± 7.8) compared with TALP alone (10.6% ± 6.1).

  15. Measuring the bioactivity and molecular conformation of typically globular proteins with phenothiazine-derived methylene blue in solid and in solution: A comparative study using photochemistry and computational chemistry.

    Science.gov (United States)

    Ding, Fei; Xie, Yong; Peng, Wei; Peng, Yu-Kui

    2016-05-01

    Methylene blue is a phenothiazine agent, that possesses a diversity of biomedical and biological therapeutic purpose, and it has also become the lead compound for the exploitation of other pharmaceuticals such as chlorpromazine and the tricyclic antidepressants. However, the U.S. Food and Drug Administration has acquired cases of detrimental effects of methylene blue toxicities such as hemolytic anemia, methemoglobinemia and phototoxicity. In this work, the molecular recognition of methylene blue by two globular proteins, hemoglobin and lysozyme was characterized by employing fluorescence, circular dichroism (CD) along with molecular modeling at the molecular scale. The recognition of methylene blue with proteins appears fluorescence quenching via static type, this phenomenon does cohere with time-resolved fluorescence lifetime decay that nonfluorescent protein-drug conjugate formation has a strength of 10(4)M(-1), and the primary noncovalent bonds, that is hydrogen bonds, π-conjugated effects and hydrophobic interactions were operated and remained adduct stable. Meantime, the results of far-UV CD and synchronous fluorescence suggest that the α-helix of hemoglobin/lysozyme decreases from 78.2%/34.7% (free) to 58.7%/23.8% (complex), this elucidation agrees well with the elaborate description of three-dimensional fluorescence showing the polypeptide chain of proteins partially destabilized upon conjugation with methylene blue. Furthermore, both extrinsic fluorescent indicator and molecular modeling clearly exhibit methylene blue is situated within the cavity constituted by α1, β2 and α2 subunits of hemoglobin, while it was located at the deep fissure on the lysozyme surface and Trp-62 and Trp-63 residues are nearby. With the aid of computational analyses and combining the wet experiments, it can evidently be found that the recognition ability of proteins for methylene blue is patterned upon the following sequence: lysozyme

  16. New insights into metal interactions with the prion protein: EXAFS analysis and structure calculations of copper binding to a single octarepeat from the prion protein.

    Science.gov (United States)

    McDonald, Alex; Pushie, M Jake; Millhauser, Glenn L; George, Graham N

    2013-11-07

    Copper coordination to the prion protein (PrP) has garnered considerable interest for almost 20 years, due in part to the possibility that this interaction may be part of the normal function of PrP. The most characterized form of copper binding to PrP has been Cu(2+) interaction with the conserved tandem repeats in the N-terminal domain of PrP, termed the octarepeats, with many studies focusing on single and multiple repeats of PHGGGWGQ. Extended X-ray absorption fine structure (EXAFS) spectroscopy has been used in several previous instances to characterize the solution structure of Cu(2+) binding into the peptide backbone in the HGGG portion of the octarepeats. All previous EXAFS studies, however, have benefitted from crystallographic structure information for [Cu(II) (Ac-HGGGW-NH2)(-2H)] but have not conclusively demonstrated that the complex EXAFS spectrum represents the same coordination environment for Cu(2+) bound to the peptide backbone. Density functional structure calculations as well as full multiple scattering EXAFS curve fitting analysis are brought to bear on the predominant coordination mode for Cu(2+) with the Ac-PHGGGWGQ-NH2 peptide at physiological pH, under high Cu(2+) occupancy conditions. In addition to the structure calculations, which provide a thermodynamic link to structural information, methods are also presented for extensive deconvolution of the EXAFS spectrum. We demonstrate how the EXAFS data can be analyzed to extract the maximum structural information and arrive at a structural model that is significantly improved over previous EXAFS characterizations. The EXAFS spectrum for the chemically reduced form of copper binding to the Ac-PHGGGWGQ-NH2 peptide is presented, which is best modeled as a linear two-coordinate species with a single His imidazole ligand and a water molecule. The extent of in situ photoreduction of the copper center during standard data collection is also presented, and EXAFS curve fitting of the photoreduced species

  17. Metallothionein-like proteins and zinc--copper interaction in the hindgut of Porcellio scaber (Crustacea: Isopoda) exposed to zinc.

    Science.gov (United States)

    Znidarsic, N; Tusek-Znidaric, M; Falnoga, I; Scancar, J; Strus, J

    2005-09-01

    Metallothioneins (MTs) are ubiquitous low-molecular-weight metal-binding proteins, with a variety of functions in metal metabolism ascribed to them. Among terrestrial invertebrates, MTs have been studied in nematodes, insects, snails, and earthworms. The aim of this study was the characterization of MT-like proteins in the terrestrial isopod crustacean Porcellio scaber in order to analyze their probable role in the metabolism of copper (Cu) and zinc (Zn). Dietary Zn supplementation (793 microg Zn/g dry food, 6 d) was applied to stimulate MT synthesis. After separation of the hindgut post-microsomic supernatant (cytosol) of Zn-exposed animals by gel filtration on a Sephadex G-75 column, a Cu- and Zn-containing peak was detected in the position of Ve/Vo approximately 2, where MTs are expected to elute. Rechromatography of these fractions by size-exclusion chromatography-high-performance liquid chromatography revealed that the 215-nm absorbance peak coincided with the absorbance peak of the rabbit MT II standard. These low-molecular-weight Cu- and Zn-binding compounds, detected in the cytosol of the hindgut cells in Zn-exposed P. scaber, are considered to be Cu, Zn-MT-like proteins. To our knowledge, this is the first report on the characterization of MT-like proteins in isopod crustaceans. These results also indicate that both Zn and Cu dynamics in P. scaber hindgut are affected at the given dietary Zn supplementation and that MT-like proteins are involved in this Zn-Cu interaction.

  18. Validation of the flooding dose technique to determine fractional rates of protein synthesis in a model bivalve species, the blue mussel (Mytilus edulis L.).

    Science.gov (United States)

    McCarthy, Ian D; Nicholls, Ruth; Malham, Shelagh K; Whiteley, Nia M

    2016-01-01

    For the first time, use of the flooding dose technique using (3)H-Phenylalanine is validated for measuring whole-animal and tissue-specific rates of protein synthesis in the blue mussel Mytilus edulis (61mm shell length; 4.0g fresh body mass). Following injection, the phenylalanine-specific radioactivities in the gill, mantle and whole-animal free pools were elevated within one hour and remained elevated and stable for up to 6h following injection of (3)H-phenylalanine into the posterior adductor muscle. Incorporation of (3)H-phenylalanine into body protein was linear over time following injection and the non-significant intercepts for the regressions suggested incorporation into body protein occurred rapidly after injection. These results validate the technique for measuring rates of protein synthesis in mussels. There were no differences in the calculated rates following 1-6h incubation in gill, mantle or whole-animal and fractional rates of protein synthesis from the combined time course data were 9.5±0.8%d(-1) for the gill, 2.5±0.3%d(-1) for the mantle and 2.6±0.3%d(-1) for the whole-animal, respectively (mean values±SEM). The whole-animal absolute rate of protein synthesis was calculated as 18.9±0.6mg protein day(-1). The use of this technique in measuring one of the major components of maintenance metabolism and growth will provide a valuable and convenient tool in furthering our understanding of the protein metabolism and energetics of this keystone marine invertebrate and its ability to adjust and respond to fluctuations, such as that expected as a result of climate change.

  19. 3D local structure around copper site of rabbit prion-related protein: Quantitative determination by XANES spectroscopy combined with multiple-scattering calculations

    Science.gov (United States)

    Cui, P. X.; Lian, F. L.; Wang, Y.; Wen, Yi; Chu, W. S.; Zhao, H. F.; Zhang, S.; Li, J.; Lin, D. H.; Wu, Z. Y.

    2014-02-01

    Prion-related protein (PrP), a cell-surface copper-binding glycoprotein, is considered to be responsible for a number of transmissible spongiform encephalopathies (TSEs). The structural conversion of PrP from the normal cellular isoform (PrPC) to the post-translationally modified form (PrPSc) is thought to be relevant to Cu2+ binding to histidine residues. Rabbits are one of the few mammalian species that appear to be resistant to TSEs, because of the structural characteristics of the rabbit prion protein (RaPrPC) itself. Here we determined the three-dimensional local structure around the C-terminal high-affinity copper-binding sites using X-ray absorption near-edge structure combined with ab initio calculations in the framework of the multiple-scattering (MS) theory. Result shows that two amino acid resides, Gln97 and Met108, and two histidine residues, His95 and His110, are involved in binding this copper(II) ion. It might help us understand the roles of copper in prion conformation conversions, and the molecular mechanisms of prion-involved diseases.

  20. Structure determination of a 16.8 kDa copper protein at 2.1 A resolution using anomalous scattering data with direct methods.

    Science.gov (United States)

    Harvey, I; Hao, Q; Duke, E M; Ingledew, W J; Hasnain, S S

    1998-07-01

    The structure of rusticyanin, an acid-stable copper protein, has been determined at 2.1 A resolution by direct methods combined with the single-wavelength anomalous scattering (SAS) of copper (f" = 3.9 e-) and then conventionally refined (Rcryst = 18.7%, Rfree = 21.9%). This is the largest unknown protein structure (Mr approximately /= 16.8 kDa) to be determined using the SAS and direct-methods approach and demonstrates that by exploiting the anomalous signal at a single wavelength, direct methods can be used to determine phases at typical (approximately 2 A) macromolecular crystallographic resolutions. Extrapolating from the size of the anomalous signal for copper (f" approximately 4 e-), this result suggests that the approach could be used for proteins with molecular weights of up to 33 kDa per Se (f"max++ = 8 e- at the 'white line') and 80 kDa for a Pt derivative (f"max = 19 e- at the 'white line', L3 edge). The method provides a powerful alternative in solving a de novo protein structure without either preparing multiple crystals (i.e. isomorphous heavy-atom derivative plus native crystals) or collecting multi-wavelength anomalous diffraction (MAD) data.

  1. Low energy method of manufacturing high-grade protein using blue-green algae of the genus Spirulina

    Energy Technology Data Exchange (ETDEWEB)

    Leesley, M.E.; Newsom, T.M.; Burleson, J.D.

    1981-01-01

    Algae are well suited to replace many conventional sources of protein because of their efficient use of energy, land, and raw materials. The most promising genus, Spirulina, is compared with conventional protein sources on the bases of energy efficiency, land usage, and production costs.

  2. PHH1, a novel gene from Arabidopsis thaliana that encodes a protein similar to plant blue-light photoreceptors and microbial photolyases.

    Science.gov (United States)

    Hoffman, P D; Batschauer, A; Hays, J B

    1996-11-27

    A cDNA from Arabidopsis thaliana similar to microbial photolyase genes, and designated AT-PHH1, was isolated using a photolyase-like cDNA from Sinapsis alba (SA-PHR1) as a probe. Multiple isolations yielded only PHH1 cDNAs, and a few blue-light-receptor CRY1 (HY4) cDNAs (also similar to microbial photolyase genes), suggesting the absence of any other highly similar Arabidopsis genes. The AT-PHH1 and SA-PHR1 cDNA sequences predict 89% identity at the protein level, except for an AT-PHH1 C-terminal extension (111 amino acids), also not seen in microbial photolyases. AT-PHH1 and CRY1 show less similarity (54% p4erein identity), including respective C-terminal extensions that are themselves mostly dissimilar. Analysis of fifteen AT-PHH1 genomic isolates reveals a single gene, with three introns in the coding sequence and one in the 5'-untranslated leader. Full-length AT-PHH1, and both AT-PHH1 and AT-PHH1 delta C-513 (truncated to be approximately the size of microbial photolyase genes) cDNAs, were overexpressed, respectively, in yeast and Escherichia coli mutants hypersensitive to ultraviolet light. The absence of significant effects on resistance suggests either that any putative AT-PHH1 DNA repair activity requires cofactors/chromophores not present in yeast or E. coli, or that AT-PHH1 encodes a blue-light/ultraviolet-A receptor rather than a DNA repair protein.

  3. OsHAL3, a Blue Light-Responsive Protein, Interacts with the Floral Regulator Hd1 to Activate Flowering in Rice.

    Science.gov (United States)

    Su, Lei; Shan, Jun-Xiang; Gao, Ji-Ping; Lin, Hong-Xuan

    2016-02-01

    In flowering plants, photoperiodic flowering is controlled by a complicated network. Light is one of the most important environmental stimuli that control the timing of the transition from vegetative growth to reproductive development. Several photoreceptors, including PHYA, PHYB, CRY2, and FKF1 in Arabidopsis and their homologs (OsPHYA, OsPHYB, OsPHYC, and OsCRY2) in rice, have been identified to be related to flowering. Our previous study suggests that OsHAL3, a flavin mononucleotide-binding protein, may function as a blue-light sensor. Here, we report the identification of OsHAL3 as a positive regulator of flowering in rice. OsHAL3 overexpression lines exhibited an early flowering phenotype, whereas downregulation of OsHAL3 expression by RNA interference delayed flowering under an inductive photoperiod (short-day conditions). The change in flowering time was not accompanied by altered Hd1 expression but rather by reduced accumulation of Hd3a and MADS14 transcripts. OsHAL3 and Hd1 colocalized in the nucleus and physically interacted in vivo under the dark, whereas their interaction was inhibited by white or blue light. Moreover, OsHAL3 directly bound to the promoter of Hd3a, especially before dawn. We conclude that OsHAL3, a novel light-responsive protein, plays an essential role in photoperiodic control of flowering time in rice, which is probably mediated by forming a complex with Hd1. Our findings open up new perspectives on the photoperiodic flowering pathway.

  4. Abnormal Copper Homeostasis: Mechanisms and Roles in Neurodegeneration

    OpenAIRE

    Mario Manto

    2014-01-01

    As a cofactor of proteins and enzymes involved in critical molecular pathways in mammals and low eukaryotes, copper is a transition metal essential for life. The intra-cellular and extra-cellular metabolism of copper is under tight control, in order to maintain free copper concentrations at very low levels. Copper is a critical element for major neuronal functions, and the central nervous system is a major target of disorders of copper metabolism. Both the accumulation of copper and copper d...

  5. Posthuman blues

    CERN Document Server

    Tonnies, Mac

    2013-01-01

    Posthuman Blues, Vol. I is first volume of the edited version of the popular weblog maintained by author Mac Tonnies from 2003 until his tragic death in 2009. Tonnies' blog was a pastiche of his original fiction, reflections on his day-to-day life, trenchant observations of current events, and thoughts on an eclectic range of material he culled from the Internet. What resulted was a remarkably broad portrait of a thoughtful man and the complex times in which he lived, rendered with intellige...

  6. Synthesis and Structure of a Ternary Copper(II) Complex with Mixed Ligands of Diethylenetriamine and Picrate: DNA/Protein-Binding Property and In Vitro Anticancer Activity Studies.

    Science.gov (United States)

    Shi, Ya-Ning; Zheng, Kang; Zhu, Ling; Li, Yan-Tuan; Wu, Zhi-Yong; Yan, Cui-Wei

    2015-05-01

    Based on the importance of the design and synthesis of transition metal complexes with noncovalent DNA/protein-binding abilities in the field of metallo pharmaceuticals, a new mononuclear ternary copper(II) complex with mixed ligands of diethylenetriamine (dien) and picrate anion (pic), identified as [Cu(dien)(pic)](pic), was synthesized and characterized by elemental analysis, molar conductivity measurement, infrared spectrum, electronic spectral studies, and single-crystal X-ray diffractometry. The structure analysis reveals that the copper(II) complex crystallizes in the monoclinic space group P21 /c, and the copper(II) ion has a distorted square pyramidal coordination geometry. A two-dimensional supramolecular structure is formed through hydrogen bonds. The DNA/bovine serum albumin (BSA)-binding properties of the complex are explored, indicating that the complex can interact with herring sperm DNA via intercalation mode and bind to BSA responsible for quenching of tryptophan fluorescence by static quenching mechanism. The in vitro anticancer activity shows that the copper(II) complex is active against the selected tumor cell lines.

  7. Long-range protein electron transfer observed at the single-molecule level

    DEFF Research Database (Denmark)

    Chi, Qijin; Farver, Ole; Ulstrup, Jens

    2005-01-01

    A biomimetic long-range electron transfer (ET) system consisting of the blue copper protein azurin, a tunneling barrier bridge, and a gold single-crystal electrode was designed on the basis of molecular wiring self-assembly principles. This system is sufficiently stable and sensitive in a quasi...

  8. Chemical composition and standardized ileal digestibility of protein and amino acids from blue mussel, starfish, and fish silage in pigs

    DEFF Research Database (Denmark)

    Nørgaard, Jens Vinther; Petersen, Jens Kjerulf; Tørring, Ditte Bruunshøj

    2015-01-01

    fish silage from farmed salmon was also included in theexperiment. The standardized ileal digestibility (SID) of crude protein (CP) and amino acids(AA) was evaluated in a Latin square design with pigs (initial weight 39.3 kg) fitted with asimple T-cannula in the terminal ileum. Diets contained 131...

  9. Cross-talk between the octarepeat domain and the fifth binding site of prion protein driven by the interaction of copper(II) with the N-terminus.

    Science.gov (United States)

    Di Natale, Giuseppe; Turi, Ildikó; Pappalardo, Giuseppe; Sóvágó, Imre; Rizzarelli, Enrico

    2015-03-02

    Prion diseases are a group of neurodegenerative diseases based on the conformational conversion of the normal form of the prion protein (PrP(C)) to the disease-related scrapie isoform (PrP(Sc)). Copper(II) coordination to PrP(C) has attracted considerable interest for almost 20 years, mainly due to the possibility that such an interaction would be an important event for the physiological function of PrP(C). In this work, we report the copper(II) coordination features of the peptide fragment Ac(PEG11)3PrP(60-114) [Ac = acetyl] as a model for the whole N-terminus of the PrP(C) metal-binding domain. We studied the complexation properties of the peptide by means of potentiometric, UV/Vis, circular dichroism and electrospray ionisation mass spectrometry techniques. The results revealed that the preferred histidyl binding sites largely depend on the pH and copper(II)/peptide ratio. Formation of macrochelate species occurs up to a 2:1 metal/peptide ratio in the physiological pH range and simultaneously involves the histidyl residues present both inside and outside the octarepeat domain. However, at increased copper(II)/peptide ratios amide-bound species form, especially within the octarepeat domain. On the contrary, at basic pH the amide-bound species predominate at any copper/peptide ratio and are formed preferably with the binding sites of His96 and His111, which is similar to the metal-binding-affinity order observed in our previous studies.

  10. Disulfiram/copper-disulfiram Damages Multiple Protein Degradation and Turnover Pathways and Cytotoxicity is Enhanced by Metformin in Oesophageal Squamous Cell Carcinoma Cell Lines.

    Science.gov (United States)

    Jivan, Rupal; Damelin, Leonard Howard; Birkhead, Monica; Rousseau, Amanda Louise; Veale, Robin Bruce; Mavri-Damelin, Demetra

    2015-10-01

    Disulfiram (DSF), used since the 1950s in the treatment of alcoholism, is reductively activated to diethyldithiocarbamate and both compounds are thiol-reactive and readily complex copper. More recently DSF and copper-DSF (Cu-DSF) have been found to exhibit potent anticancer activity. We have previously shown that the anti-diabetic drug metformin is anti-proliferative and induces an intracellular reducing environment in oesophageal squamous cell carcinoma (OSCC) cell lines. Based on these observations, we investigated the effects of Cu-DSF and DSF, with and without metformin, in this present study. We found that Cu-DSF and DSF caused considerable cytotoxicity across a panel of OSCC cells, and metformin significantly enhanced the effects of DSF. Elevated copper transport contributes to DSF and metformin-DSF-induced cytotoxicity since the cell-impermeable copper chelator, bathocuproinedisulfonic acid, partially reversed the cytotoxic effects of these drugs, and interestingly, metformin-treated OSCC cells contained higher intracellular copper levels. Furthermore, DSF may target cancer cells preferentially due to their high dependence on protein degradation/turnover pathways, and we found that metformin further enhances the role of DSF as a proteasome inhibitor. We hypothesized that the lysosome could be an additional, novel, target of DSF. Indeed, this acid-labile compound decreased lysosomal acidification, and DSF-metformin co-treatment interfered with the progression of autophagy in these cells. In summary, this is the first such report identifying the lysosome as a target of DSF and based on the considerable cytotoxic effects of DSF either alone or in the presence of metformin, in vitro, and we propose these as novel potential chemotherapeutic approaches for OSCC.

  11. Evaluation of the protein biomarkers and the analgesic response to systemic methylene blue in patients with refractory neuropathic pain: a double-blind, controlled study

    Directory of Open Access Journals (Sweden)

    Miclescu AA

    2015-07-01

    Full Text Available Adriana A Miclescu,1 Martin Svahn,1 Torsten E Gordh1,2 1Multidisciplinary Pain Clinic, Uppsala University Hospital, 2Pain Research, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden Aim: This study was carried out in patients with neuropathic pain in order to assess the analgesic effects and changes in protein biomarkers after the administration of methylene blue (MB, a diaminophenothiazine with antioxidant and anti-inflammatory properties, and with inhibitory effects on nitric oxide.Materials and methods: Ten patients with chronic refractory neuropathic pain were randomized to receive either MB (10 mg/mL Methylthioninium chloride 2 mg/kg (MB group or MB 0.02 mg/kg (control group infused over 60 minutes. Sensory function and pain (Numerical Rating Scale were evaluated at baseline and at 60 minutes after the start of the infusion. The patients kept a pain diary during the next 24 hours and for the following 4 days. Plasma and urinary concentrations of 8-isoprostane-prostaglandin F2α (8-iso-PGF2α and plasma protein biomarkers prior to and after the infusions were measured with radioimmunoassay and with proximity extension assay.Results: A decrease of the Numerical Rating Scale at 60 minutes in comparison with baseline was observed in the MB (P=0.047 group. The decrease was significant between the MB and the control group on the day of and day after MB infusion (P=0.04 and P=0.008, respectively. There was no difference in systemic protein expressions between groups except for prolactin (PRL (P=0.02. Three patients demonstrated diminished dynamic mechanical allodynia.Conclusion: MB decreased the pain levels in patients with chronic therapy-resistant neuropathic pain on the first 2 days after administration. Known as an endocrine modulator on the anterior pituitary gland, MB infusion produced a decrease of PRL. The detailed role of PRL effects in chronic neuropathic pain remains undetermined.Keywords: methylene blue, nitric oxide

  12. Copper hypersensitivity.

    Science.gov (United States)

    Fage, Simon W; Faurschou, Annesofie; Thyssen, Jacob P

    2014-10-01

    The world production of copper is steadily increasing. Although humans are widely exposed to copper-containing items on the skin and mucosa, allergic reactions to copper are only infrequently reported. To review the chemistry, biology and accessible data to clarify the implications of copper hypersensitivity, a database search of PubMed was performed with the following terms: copper, dermatitis, allergic contact dermatitis, contact hypersensitivity, contact sensitization, contact allergy, patch test, dental, IUD, epidemiology, clinical, and experimental. Human exposure to copper is relatively common. As a metal, it possesses many of the same qualities as nickel, which is a known strong sensitizer. Cumulative data on subjects with presumed related symptoms and/or suspected exposure showed that a weighted average of 3.8% had a positive patch test reaction to copper. We conclude that copper is a very weak sensitizer as compared with other metal compounds. However, in a few and selected cases, copper can result in clinically relevant allergic reactions.

  13. Proteomic Analysis of Copper-Binding Proteins in Excess Copper-Stressed Roots of Two Rice (Oryza sativa L. Varieties with Different Cu Tolerances.

    Directory of Open Access Journals (Sweden)

    Chen Chen

    Full Text Available To better understand the mechanisms involved in the heavy metal stress response and tolerance in plants, a proteomic approach was used to investigate the differences in Cu-binding protein expression in Cu-tolerant and Cu-sensitive rice varieties. Cu-binding proteins from Cu-treated rice roots were separated using a new IMAC method in which an IDA-sepharose column was applied prior to the Cu-IMAC column to remove metal ions from protein samples. More than 300 protein spots were reproducibly detected in the 2D gel. Thirty-five protein spots exhibited changes greater than 1.5-fold in intensity compared to the control. Twenty-four proteins contained one or more of nine putative metal-binding motifs reported by Smith et al., and 19 proteins (spots contained one to three of the top six motifs reported by Kung et al. The intensities of seven protein spots were increased in the Cu-tolerant variety B1139 compared to the Cu-sensitive variety B1195 (p<0.05 and six protein spots were markedly up-regulated in B1139, but not detectable in B1195. Four protein spots were significantly up-regulated in B1139, but unchanged in B1195 under Cu stress. In contrast, two protein spots were significantly down-regulated in B1195, but unchanged in B1139. These Cu-responsive proteins included those involved in antioxidant defense and detoxification (spots 5, 16, 21, 22, 28, 29 and 33, pathogenesis (spots 5, 16, 21, 22, 28, 29 and 33, regulation of gene transcription (spots 8 and 34, amino acid synthesis (spots 8 and 34, protein synthesis, modification, transport and degradation (spots 1, 2, 4, 10, 15, 19, 30, 31, 32 and 35, cell wall synthesis (spot 14, molecular signaling (spot 3, and salt stress (spots 7, 9 and 27; together with other proteins, such as a putative glyoxylate induced protein, proteins containing dimeric alpha-beta barrel domains, and adenosine kinase-like proteins. Our results suggest that these proteins, together with related physiological processes, play

  14. Development of a spectroscopic assay for bifunctional ligand-protein conjugates based on copper

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Erik D. E-mail: bradye@mail.nih.gov; Chong, Hyun-Soon; Milenic, Diane E.; Brechbiel, Martin W

    2004-08-01

    A simple, non-radioactive method for the determination of ligand-to-protein ratio (L/P) for novel ligand-antibody conjugates has been developed based on an exchange equilibrium with the purple Cu(II) complex of arsenazo III. The method requires a UV/Vis spectrometer and has been verified for monoclonal antibody Herceptin conjugates of a variety of ligand modalities, including common macrocyclic compounds NOTA and TETA, and with a new bifunctional tachpyridine (1H-Pyrrole-1-butanamide,N-[4-[[(1{alpha},3{alpha},5{alpha})-3,5-bis[(2-pyridi= nylmethyl) amino]cyclohexyl](2-pyridinylmethyl)amino]butyl]-2,5-dihydro-2, 5-dioxo-(9CI)). The spectroscopically derived values for L/P were verified by titration of the ligand-antibody conjugate with {sup 64}Cu. In each case, the value obtained by UV/Vis spectroscopy matches that found by radiolabeling. The method is rapid, taking less than 30 minutes with each ligand in this study.

  15. A novel copper(II) coordination at His186 in full-length murine prion protein

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Yasuko [Laboratory of Radiation Biology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818 (Japan); Hiraoka, Wakako [Laboratory of Biophysics, School of Science and Technology, Meiji University, Kawasaki 214-8571 (Japan); Igarashi, Manabu; Ito, Kimihito [Department of Global Epidemiology, Hokkaido University Research Center for Zoonosis Control, Sapporo 001-0020 (Japan); Shimoyama, Yuhei [Soft-Matter Physics Laboratory, Graduate School of Emergent Science, Muroran Institute of Technology, Muroran 050-8585 (Japan); Horiuchi, Motohiro [Laboratory of Prion Diseases, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818 (Japan); Yamamori, Tohru; Yasui, Hironobu; Kuwabara, Mikinori [Laboratory of Radiation Biology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818 (Japan); Inagaki, Fuyuhiko [Laboratory of Structural Biology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812 (Japan); Inanami, Osamu, E-mail: inanami@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818 (Japan)

    2010-04-09

    To explore Cu(II) ion coordination by His{sup 186} in the C-terminal domain of full-length prion protein (moPrP), we utilized the magnetic dipolar interaction between a paramagnetic metal, Cu(II) ion, and a spin probe introduced in the neighborhood of the postulated binding site by the spin labeling technique (SDSL technique). Six moPrP mutants, moPrP(D143C), moPrP(Y148C), moPrP(E151C), moPrP(Y156C), moPrP(T189C), and moPrP(Y156C,H186A), were reacted with a methane thiosulfonate spin probe and a nitroxide residue (R1) was created in the binding site of each one. Line broadening of the ESR spectra was induced in the presence of Cu(II) ions in moPrP(Y148R1), moPrP(Y151R1), moPrP(Y156R1), and moPrP(T189R1) but not moPrP(D143R1). This line broadening indicated the presence of electron-electron dipolar interaction between Cu(II) and the nitroxide spin probe, suggesting that each interspin distance was within 20 A. The interspin distance ranges between Cu(II) and the spin probes of moPrP(Y148R1), moPrP(Y151R1), moPrP(Y156R1), and moPrP(T189R1) were estimated to be 12.1 A, 18.1 A, 10.7 A, and 8.4 A, respectively. In moPrP(Y156R1,H186A), line broadening between Cu(II) and the spin probe was not observed. These results suggest that a novel Cu(II) binding site is involved in His186 in the Helix2 region of the C-terminal domain of moPrP{sup C}.

  16. [Protein and energy value of spiruline blue algae supplemented by amino acids: digestive and metabolic utilization by the growing rat].

    Science.gov (United States)

    Vermorel, M; Toullec, G; Dumond, D; Pion, R

    1975-01-01

    Protein and energy value of 6 samples of "Spirulina" was studied on growing rats in 1972 and 1973. Sample RL 1(Spirulina platensis, originating from Tchad) was grown in artifical conditions in a laboratory. Others samples (Spirulina maxima) were grown in the solar evaporator near Mexico, washed and dried either on heated rollers (MR8, MR13) or by spraying (MA 7, MA10). Sample MA10 D corresponds to sample MA10, bleached by ethanol plus acetone (Baron, 1975). Each Spirulina sample was the only protein source of balanced, starch diets. The diets were supplemented in essential amino acids (E.A.A.) according to the requirements of growing rats (table 1). The ratios [(digestible nitrogen/metabolisable energy (EM] of the Spirulina diets were similar to that of the control diets containing herring meal. The diets were fed to groups of 15 to 17 growing rats. Energy and nitrogen balances were established by the comparative slaughter technique. Blood and muscle samples were taken at slaughter for the determination of free amino acids levels.

  17. Color vision: retinal blues.

    Science.gov (United States)

    Johnston, Jamie; Esposti, Federico; Lagnado, Leon

    2012-08-21

    Two complementary studies have resolved the circuitry underlying green-blue color discrimination in the retina. A blue-sensitive interneuron provides the inhibitory signal required for computing green-blue color opponency.

  18. Copper hypersensitivity

    DEFF Research Database (Denmark)

    Fage, Simon W; Faurschou, Annesofie; Thyssen, Jacob P

    2014-01-01

    hypersensitivity, a database search of PubMed was performed with the following terms: copper, dermatitis, allergic contact dermatitis, contact hypersensitivity, contact sensitization, contact allergy, patch test, dental, IUD, epidemiology, clinical, and experimental. Human exposure to copper is relatively common...

  19. The effect of driving force on intramolecular electron transfer in proteins. Studies on single-site mutated azurins

    DEFF Research Database (Denmark)

    Farver, O; Skov, L K; van de Kamp, M;

    1992-01-01

    An intramolecular electron-transfer process has previously been shown to take place between the Cys3--Cys26 radical-ion (RSSR-) produced pulse radiolytically and the Cu(II) ion in the blue single-copper protein, azurin [Farver, O. & Pecht, I. (1989) Proc. Natl Acad. Sci. USA 86, 6868-6972]. To fu...

  20. Needles in the blue sea: sub-species specificity in targeted protein biomarker analyses within the vast oceanic microbial metaproteome.

    Science.gov (United States)

    Saito, Mak A; Dorsk, Alexander; Post, Anton F; McIlvin, Matthew R; Rappé, Michael S; DiTullio, Giacomo R; Moran, Dawn M

    2015-10-01

    Proteomics has great potential for studies of marine microbial biogeochemistry, yet high microbial diversity in many locales presents us with unique challenges. We addressed this challenge with a targeted metaproteomics workflow for NtcA and P-II, two nitrogen regulatory proteins, and demonstrated its application for cyanobacterial taxa within microbial samples from the Central Pacific Ocean. Using METATRYP, an open-source Python toolkit, we examined the number of shared (redundant) tryptic peptides in representative marine microbes, with the number of tryptic peptides shared between different species typically being 1% or less. The related cyanobacteria Prochlorococcus and Synechococcus shared an average of 4.8 ± 1.9% of their tryptic peptides, while shared intraspecies peptides were higher, 13 ± 15% shared peptides between 12 Prochlorococcus genomes. An NtcA peptide was found to target multiple cyanobacteria species, whereas a P-II peptide showed specificity to the high-light Prochlorococcus ecotype. Distributions of NtcA and P-II in the Central Pacific Ocean were similar except at the Equator likely due to differential nitrogen stress responses between Prochlorococcus and Synechococcus. The number of unique tryptic peptides coded for within three combined oceanic microbial metagenomes was estimated to be ∼4 × 10(7) , 1000-fold larger than an individual microbial proteome and 27-fold larger than the human proteome, yet still 20 orders of magnitude lower than the peptide diversity possible in all protein space, implying that peptide mapping algorithms should be able to withstand the added level of complexity in metaproteomic samples.

  1. Expression of a vacuole-localized BURP-domain protein from soybean (SALI3-2 enhances tolerance to cadmium and copper stresses.

    Directory of Open Access Journals (Sweden)

    Yulin Tang

    Full Text Available The plant-specific BURP family proteins play diverse roles in plant development and stress responses, but the function mechanism of these proteins is still poorly understood. Proteins in this family are characterized by a highly conserved BURP domain with four conserved Cys-His repeats and two other Cys, indicating that these proteins potentially interacts with metal ions. In this paper, an immobilized metal affinity chromatography (IMAC assay showed that the soybean BURP protein SALI3-2 could bind soft transition metal ions (Cd(2+, Co(2+, Ni(2+, Zn(2+ and Cu(2+ but not hard metal ions (Ca(2+ and Mg(2+ in vitro. A subcellular localization analysis by confocal laser scanning microscopy revealed that the SALI3-2-GFP fusion protein was localized to the vacuoles. Physiological indexes assay showed that Sali3-2-transgenic Arabidopsis thaliana seedlings were more tolerant to Cu(2+ or Cd(2+ stresses than the wild type. An inductively coupled plasma optical emission spectrometry (ICP-OES analysis illustrated that, compared to the wild type seedlings the Sali3-2-transgenic seedlings accumulated more cadmium or copper in the roots but less in the upper ground tissues when the seedlings were exposed to excessive CuCl2 or CdCl2 stress. Therefore, our findings suggest that the SALI3-2 protein may confer cadmium (Cd(2+ and copper (Cu(2+ tolerance to plants by helping plants to sequester Cd(2+ or Cu(2+ in the root and reduce the amount of heavy metals transported to the shoots.

  2. Natural Blue Food Colour

    DEFF Research Database (Denmark)

    Roda-Serrat, Maria Cinta

    2017-01-01

    the presence of the chromophore phycocyanobilin (PCB), a covalently attached linear tetrapyrrole. The applications of phycocyanins as food colorants are however limited, as they show poor stability in certain conditions of pH, light and temperature. Cleavage of PCB from the protein followed by careful product...... decreased. PCB was also found to be more sensitive to pH than phycocyanin. Regarding the stability with time, PCB showed a similar stability at pH 3, and worse at pH 5 and pH 7. The change from blue to green colour in acid conditions was attributed to protonation of the chromophore. However, the effect...

  3. Presenilin promotes dietary copper uptake.

    Directory of Open Access Journals (Sweden)

    Adam Southon

    Full Text Available Dietary copper is essential for multicellular organisms. Copper is redox active and required as a cofactor for enzymes such as the antioxidant Superoxide Dismutase 1 (SOD1. Copper dyshomeostasis has been implicated in Alzheimer's disease. Mutations in the presenilin genes encoding PS1 and PS2 are major causes of early-onset familial Alzheimer's disease. PS1 and PS2 are required for efficient copper uptake in mammalian systems. Here we demonstrate a conserved role for presenilin in dietary copper uptake in the fly Drosophila melanogaster. Ubiquitous RNA interference-mediated knockdown of the single Drosophila presenilin (PSN gene is lethal. However, PSN knockdown in the midgut produces viable flies. These flies have reduced copper levels and are more tolerant to excess dietary copper. Expression of a copper-responsive EYFP construct was also lower in the midgut of these larvae, indicative of reduced dietary copper uptake. SOD activity was reduced by midgut PSN knockdown, and these flies were sensitive to the superoxide-inducing chemical paraquat. These data support presenilin being needed for dietary copper uptake in the gut and so impacting on SOD activity and tolerance to oxidative stress. These results are consistent with previous studies of mammalian presenilins, supporting a conserved role for these proteins in mediating copper uptake.

  4. BIOGENESIS OF THYLAKOID MEMBRANES WITH RECONSTRUCTION OF CHLOROPHYLL-PROTEIN COMPLEXES IN DELETION-MUTANT OF ORF469 IN BLUE-GREEN ALGA

    Institute of Scientific and Technical Information of China (English)

    WuQingyu; WangRuiyong; XuHong; WireVermaas

    1997-01-01

    The transformable blue green alga is used productively for mutation and deletion studies to provide functional information regarding photosynthetic reaction center complexes. We wish to take the application of transformable blue-green algal systems one step further ,and set out the

  5. Studies of copper transport in mammalian cells using copper radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Camakaris, J.; Voskoboinik, I.; Brooks, H.; Greenough, M. [University of Melbourne, Parkville, VIC (Australia). Department of Genetics; Smith, S. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia). Radiopharmaceuticals Division; Mercer, J. [Deakin University, Clayton, VIC (Australia). Centre of Cellular and Molecular Biology

    1998-12-31

    The trace element copper poses a major problem for all organisms. It is essential as a number of vital enzymes require it. Copper deficiency can lead to neurological disorders, osteoporosis and weakening of arteries. However Cu is also highly toxic and homeostatic mechanisms have evolved to maintain Cu at levels which satisfy requirements but do not cause toxicity. Toxicity is mediated by the oxidative capacity of Cu and its ability to generate toxic free radicals. There are several acquired and inherited diseases due to either Cu toxicity or Cu deficiency. The study of these diseases facilitates identification of genes and proteins involved in copper homeostasis, and this in turn will provide rational therapeutic approaches. Using the copper radioisotopes {sup 64}Cu (t1/2 = 12.8 hr) and {sup 67}Cu (t1/2 = 61 hr) we have developed a number of systems for studying copper transport in mammalian cells. These include investigation of copper uptake, copper efflux and ligand blot assays for Cu-binding proteins. Our studies have focused on Menkes disease which is an inherited and usually lethal copper deficiency disorder in humans. We have demonstrated that the Menkes protein is directly involved as a copper efflux pump in mammalian cells. Using cells overexpressing the Menkes protein we have provided the first biochemical evidence that this functions as a Cu translocating (across the membrane) P-type ATPase (Voskoboinik et al., FEBS Letters, in press). These studies were carried out using purified plasma membrane vesicles. We are now carrying out structure- function studies on this protein using targeted mutations and assaying using the radiocopper vesicle assay. Recently we have commenced studies on the role of amyloid precursor protein (APP) in copper transport and relationship of this to Alzheimers disease

  6. Copper-sulfenate complex from oxidation of a cavity mutant of Pseudomonas aeruginosa azurin.

    Science.gov (United States)

    Sieracki, Nathan A; Tian, Shiliang; Hadt, Ryan G; Zhang, Jun-Long; Woertink, Julia S; Nilges, Mark J; Sun, Furong; Solomon, Edward I; Lu, Yi

    2014-01-21

    Metal-sulfenate centers are known to play important roles in biology and yet only limited examples are known due to their instability and high reactivity. Herein we report a copper-sulfenate complex characterized in a protein environment, formed at the active site of a cavity mutant of an electron transfer protein, type 1 blue copper azurin. Reaction of hydrogen peroxide with Cu(I)-M121G azurin resulted in a species with strong visible absorptions at 350 and 452 nm and a relatively low electron paramagnetic resonance gz value of 2.169 in comparison with other normal type 2 copper centers. The presence of a side-on copper-sulfenate species is supported by resonance Raman spectroscopy, electrospray mass spectrometry using isotopically enriched hydrogen peroxide, and density functional theory calculations correlated to the experimental data. In contrast, the reaction with Cu(II)-M121G or Zn(II)-M121G azurin under the same conditions did not result in Cys oxidation or copper-sulfenate formation. Structural and computational studies strongly suggest that the secondary coordination sphere noncovalent interactions are critical in stabilizing this highly reactive species, which can further react with oxygen to form a sulfinate and then a sulfonate species, as demonstrated by mass spectrometry. Engineering the electron transfer protein azurin into an active copper enzyme that forms a copper-sulfenate center and demonstrating the importance of noncovalent secondary sphere interactions in stabilizing it constitute important contributions toward the understanding of metal-sulfenate species in biological systems.

  7. Site-specific copper-catalyzed oxidation of α-synuclein: tightening the link between metal binding and protein oxidative damage in Parkinson's disease.

    Science.gov (United States)

    Miotto, Marco C; Rodriguez, Esaú E; Valiente-Gabioud, Ariel A; Torres-Monserrat, Valentina; Binolfi, Andrés; Quintanar, Liliana; Zweckstetter, Markus; Griesinger, Christian; Fernández, Claudio O

    2014-05-05

    Amyloid aggregation of α-synuclein (AS) has been linked to the pathological effects associated with Parkinson's disease (PD). Cu(II) binds specifically at the N-terminus of AS and triggers its aggregation. Site-specific Cu(I)-catalyzed oxidation of AS has been proposed as a plausible mechanism for metal-enhanced AS amyloid formation. In this study, Cu(I) binding to AS was probed by NMR spectroscopy, in combination with synthetic peptide models, site-directed mutagenesis, and C-terminal-truncated protein variants. Our results demonstrate that both Met residues in the motif (1)MDVFM(5) constitute key structural determinants for the high-affinity binding of Cu(I) to the N-terminal region of AS. The replacement of one Met residue by Ile causes a dramatic decrease in the binding affinity for Cu(I), whereas the removal of both Met residues results in a complete lack of binding. Moreover, these Met residues can be oxidized rapidly after air exposure of the AS-Cu(I) complex, whereas Met-116 and Met-127 in the C-terminal region remain unaffected. Met-1 displays higher susceptibility to oxidative damage compared to Met-5 because it is directly involved in both Cu(II) and Cu(I) coordination, resulting in closer exposure to the reactive oxygen species that may be generated by the redox cycling of copper. Our findings support a mechanism where the interaction of AS with copper ions leads to site-specific metal-catalyzed oxidation in the protein under physiologically relevant conditions. In light of recent biological findings, these results support a role for AS-copper interactions in neurodegeneration in PD.

  8. Exposure copper heavy metal (Cu on freshwater mussel (Anodonta woodiana and its relation to Cu and protein content in the body shell

    Directory of Open Access Journals (Sweden)

    EDWI MAHAJOENO

    2010-01-01

    Full Text Available Kurnia AI, Purwanto E, Mahajoeno E. 2010. Exposure copper heavy metal (Cu on freshwater mussel (Anodonta woodiana and its relation to Cu and protein content in the body shell. Nusantara Bioscience 2: 48-53. To determine the relationship of Cu exposure in water to the freshwater mussel exposure experiment is conducted with water containing Cu. Which measured the influence of Cu and protein content in the body shell. This study used the freshwater mussel species, Anodonta woodiana. Oysters were exposed for four weeks in the water with Cu concentration of 0.02 ppm, 0.04 ppm, 0.06 ppm and 0.00 ppm control. Cu content and protein content in the body shells are checked every week. Cu analysis was done by AAS method and the protein content using Kjeldahl method. Cu analysis showed elevated levels of Cu in mussel body after exposure. The pattern of increase in Cu content was not the same, where the pattern of the largest increases occurred after the fourth week. The statistical test showed no significant effect between the treatment with Cu accumulation in the body shell. Protein analysis showed an increase of protein content after exposure of the second week and decreased after the third and fourth weeks. The pattern of changes in protein content varied among the various treatments. The statistical test showed no significant effect between treatment with the protein changes in the body shell. Correlation test of the relationship between concentration of Cu in mussel body protein level showed a positive correlation between them with a fairly good level of relationship (correlation coefficient r = 0.836.

  9. CuO/γ-Al2O3三维电极体系催化降解染料直接铜盐蓝2R的研究%Research of Catalytic Degradation of Direct Copper Blue 2R by Three-dimensional Electrode System with CuO/γ-Al2O3 Particle Electrodes

    Institute of Scientific and Technical Information of China (English)

    张永刚; 张扬; 张丽娟

    2014-01-01

    直接铜盐蓝2R具有典型的染料分子所具备的偶氮键发色基团及羟基、氨基等助色基团。实验以活性氧化铝为载体硝酸铜溶液为前躯体,通过浸渍焙烧法制得催化性能良好的CuO/γ-Al2O3颗粒,以此作为三维电极体系内填充粒子。通过自制三维电极反应器采用间歇的实验方式处理不同浓度的直接铜盐蓝2R染料废水,对反应后废水进行UV-Vis,FTIR,COD,氨氮和色度测定以反映处理效果。FTIR前后对比结果表明,反应使得苯环和萘环上的C-N断裂,形成了磺酸基和羟基1,4取代的萘环结构,偶氮结构连接的苯环醚的中间产物。 UV-Vis结果显示反应后的溶液紫外特征吸收峰消失,表明体系对该染料脱色效果明显。%Direct copper blue 2R has the typical chromophoric group of dye such as azo linkage and auxochrome group such as hydroxy and amino. Electrocatalytic oxidation of direct copper blue 2R was investigated in the presence of copper oxide supported on γ-Al2O3 as particle electrodes which was made by method of Impregnation Calcination. The particles were filled in the three-dimensional electrode system. Batch-type study was carried on the homemade reactor to degradation kinds of concentration. The FTIR results indicated the C-N bond of benzene ring and naphthalene nucleus was broken, which formed intermediate products structure of Naphthalene ring 1, 4 replaced by sulfonic acid group and hydroxy connected the azo. The UV-Vis results indicated the characteristics of ultraviolet absorption peak of organics disappeared which meant dyes decolorizing effect of this system was obvious.

  10. Comparative genomic analyses of copper transporters and cuproproteomes reveal evolutionary dynamics of copper utilization and its link to oxygen.

    Directory of Open Access Journals (Sweden)

    Perry G Ridge

    Full Text Available Copper is an essential trace element in many organisms and is utilized in all domains of life. It is often used as a cofactor of redox proteins, but is also a toxic metal ion. Intracellular copper must be carefully handled to prevent the formation of reactive oxygen species which pose a threat to DNA, lipids, and proteins. In this work, we examined patterns of copper utilization in prokaryotes by analyzing the occurrence of copper transporters and copper-containing proteins. Many organisms, including those that lack copper-dependent proteins, had copper exporters, likely to protect against copper ions that inadvertently enter the cell. We found that copper use is widespread among prokaryotes, but also identified several phyla that lack cuproproteins. This is in contrast to the use of other trace elements, such as selenium, which shows more scattered and reduced usage, yet larger selenoproteomes. Copper transporters had different patterns of occurrence than cuproproteins, suggesting that the pathways of copper utilization and copper detoxification are independent of each other. We present evidence that organisms living in oxygen-rich environments utilize copper, whereas the majority of anaerobic organisms do not. In addition, among copper users, cuproproteomes of aerobic organisms were larger than those of anaerobic organisms. Prokaryotic cuproproteomes were small and dominated by a single protein, cytochrome c oxidase. The data are consistent with the idea that proteins evolved to utilize copper following the oxygenation of the Earth.

  11. 光照对考马斯亮蓝法测定蛋白质浓度影响的研究%Light Effect on the Determination of Protein Concentration by Coomassie Brilliant Blue Method

    Institute of Scientific and Technical Information of China (English)

    赵卓; 籍浩天; 刘东波; 嵇雅茹; 郝锡联

    2015-01-01

    This study aimed to investigate the effects of light effect on determination of protein concentration with Coomassie Brilliant Blue method,thus proving advice and guidance for accurate determination of protein concentration. With Coomassie Brilliant Blue method,the concentrations of different bovine serum albumin samples were determined under different light and incubation time. The results showed as follow:when the determination range of protein concentration was 0 ~100 μg/ml,the deviation of protein concentration is the lowest under darkness. Under darkness and room light,the higher range of protein concentration( 50 ~75 μg/ml )was lower deviation than the lowerer range of protein concentration(5~25 μg/ml). Meanwhile,Under darkness and room light,Only whitin incubation 30 min between the 50~75μg/ml protein concentration and Coomassie brilliant blue showed the lowest and the moststable deviation. Therefore,light,sample concentration and incubation time were important factors affecting the accuracy of experimental results in determination of protein concentration with Coomassie Brilliant Blue method.%通过考马斯亮蓝法测定在不同光照和孵育时间下对已知不同浓度的牛血清蛋白的影响。结果显示,在0~100μg/ml蛋白质浓度标准曲线测定范围内,黑暗环境测定蛋白质误差率最小。在黑暗和弱光条件下高浓度蛋白质组(50~75μg/ml)误差率最低显著低于低浓度蛋白质组(5~25μg/ml)。在黑暗和弱光条件下浓度在50~75μg/ml范围内的蛋白质与染料孵育30 min以内时误差率较低且较稳定。因此,采用考马斯亮蓝法测定蛋白质浓度时,环境光照、待测样品浓度以及染料与蛋白质孵育时间等是决定实验结果准确性的重要因子。

  12. Human Thyroid Cancer-1 (TC-1 is a vertebrate specific oncogenic protein that protects against copper and pro-apoptotic genes in yeast

    Directory of Open Access Journals (Sweden)

    Natalie K. Jones

    2015-07-01

    Full Text Available The human Thyroid Cancer-1 (hTC-1 protein, also known as C8orf4 was initially identified as a gene that was up-regulated in human thyroid cancer. Here we show that hTC-1 is a peptide that prevents the effects of over-expressing Bax in yeast. Analysis of the 106 residues of hTC-1 in available protein databases revealed direct orthologues in jawed-vertebrates, including mammals, frogs, fish and sharks. No TC-1 orthologue was detected in lower organisms, including yeast. Here we show that TC-1 is a general pro-survival peptide since it prevents the growth- and cell death-inducing effects of copper in yeast. Human TC-1 also prevented the deleterious effects that occur due to the over-expression of a number of key pro-apoptotic peptides, including YCA1, YBH3, NUC1, and AIF1. Even though the protective effects were more pronounced with the over-expression of YBH3 and YCA1, hTC-1 could still protect yeast mutants lacking YBH3 and YCA1 from the effects of copper sulfate. This suggests that the protective effects of TC-1 are not limited to specific pathways or processes. Taken together, our results indicate that hTC-1 is a pro-survival protein that retains its function when heterologously expressed in yeast. Thus yeast is a useful model to characterize the potential roles in cell death and survival of cancer related genes.

  13. Blue cures blue but be cautious

    Directory of Open Access Journals (Sweden)

    Pranav Sikka

    2011-01-01

    Full Text Available Methemoglobinemia is a disorder characterized by the presence of >1% methemoglobin (metHb in the blood. Spontaneous formation of methemoglobin is normally counteracted by protective enzyme systems, for example, nicotinamide adenine dinucleotide phosphate (NADPH methemoglobin reductase. Methemoglobinemia is treated with supplemental oxygen and methylene blue (1-2 mg/kg administered slow intravenously, which acts by providing an artificial electron acceptor for NADPH methemoglobin reductase. But known or suspected glucose-6-phosphate dehydrogenase (G6PD deficiency is a relative contraindication to the use of methylene blue because G6PD is the key enzyme in the formation of NADPH through pentose phosphate pathway and G6PD-deficient individuals generate insufficient NADPH to efficiently reduce methylene blue to leukomethylene blue, which is necessary for the activation of the NADPH-dependent methemoglobin reductase system. So, we should be careful using methylene blue in methemoglobinemia patient before G6PD levels.

  14. Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierrae from California

    Science.gov (United States)

    Purvis, O.W.; Bennett, J.P.; Spratt, J.

    2011-01-01

    An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour. Copyright ?? 2011 British Lichen Society.

  15. Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierra from California

    Science.gov (United States)

    Purvis, O.W.; Bennett, J.P.; Spratt, J.

    2011-01-01

    An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour.

  16. Combining blue native polyacrylamide gel electrophoresis with liquid chromatography tandem mass spectrometry as an effective strategy for analyzing potential membrane protein complexes of Mycobacterium bovis bacillus Calmette-Guérin

    Directory of Open Access Journals (Sweden)

    Li Weijun

    2011-01-01

    Full Text Available Abstract Background Tuberculosis is an infectious bacterial disease in humans caused primarily by Mycobacterium tuberculosis, and infects one-third of the world's total population. Mycobacterium bovis bacillus Calmette-Guérin (BCG vaccine has been widely used to prevent tuberculosis worldwide since 1921. Membrane proteins play important roles in various cellular processes, and the protein-protein interactions involved in these processes may provide further information about molecular organization and cellular pathways. However, membrane proteins are notoriously under-represented by traditional two-dimensional polyacrylamide gel electrophoresis (2-D PAGE and little is known about mycobacterial membrane and membrane-associated protein complexes. Here we investigated M. bovis BCG by an alternative proteomic strategy coupling blue native PAGE to liquid chromatography tandem mass spectrometry (LC-MS/MS to characterize potential protein-protein interactions in membrane fractions. Results Using this approach, we analyzed native molecular composition of protein complexes in BCG membrane fractions. As a result, 40 proteins (including 12 integral membrane proteins, which were organized in 9 different gel bands, were unambiguous identified. The proteins identified have been experimentally confirmed using 2-D SDS PAGE. We identified MmpL8 and four neighboring proteins that were involved in lipid transport complexes, and all subunits of ATP synthase complex in their monomeric states. Two phenolpthiocerol synthases and three arabinosyltransferases belonging to individual operons were obtained in different gel bands. Furthermore, two giant multifunctional enzymes, Pks7 and Pks8, and four mycobacterial Hsp family members were determined. Additionally, seven ribosomal proteins involved in polyribosome complex and two subunits of the succinate dehydrogenase complex were also found. Notablely, some proteins with high hydrophobicity or multiple transmembrane

  17. 考马斯亮蓝法测定奶粉真蛋白的研究%The determination of true protein in milk powder with coomassie brilliant blue method

    Institute of Scientific and Technical Information of China (English)

    董娜; 贾艳菊; 张晓; 齐志广

    2011-01-01

    比较凯氏定氮法、考马斯亮蓝法和福林酚法测定奶粉蛋白含量的差异,研究了不同种类的非蛋白含氮物(尿素、三聚氰胺、甘氨酸和水解蛋白)、不同添加量(0%、0.5%、1%、2%和10%)对考马斯亮蓝法测定奶粉蛋白含量的影响。实验结果为,考马斯亮法所测蛋白含量与凯氏定氮法相近,福林酚法测定的结果显著高于凯氏定氮法;添加不同比例的4种非蛋白含氮物均对考马斯亮蓝法测定蛋白含量的结果没有影响,随着添加比例的增加,奶粉氮含量的理论值逐渐增大,而测定值没有显著变化。实验结果表明,考马斯亮法可排除添加非蛋白含氮物对奶粉真蛋白含量测定的影响,可以快速、准确的测定奶粉真蛋白含量。%The protein content in milk powder with Kjeldahl nitrogen method, Coomassie brilliant blue method and lowry method were compared, and the effects of adding urea, melamine, glycine and hydrolyzed protein with different content (0%, 0.5%, 1%, 2% and 10%) in mill powder on the protein content determined with coomassie brilliant blue method were studied. The protein content determined with coomassie brilliant blue method was similar to that determined with Kjeldahl nitrogen method, protein content determined with lowry method was significantly higher than that determined with Kjeldahl nitrogen method. The addition of non-protein nitrogen compound had no significant effects on the protein content determined with coomassie brilliant blue method. The theoretical data of nitrogen content in milk powder increased with the addition content of non-protein nitrogen compound, but the determined data had no significant changes. Those results indicate that coomassie brilliant blue method can prevent the interference of the addition of non-protein nitrogen compound on true protein determination, and can determine the true protein content in milk powder quickly and

  18. Copper: From neurotransmission to neuroproteostasis

    Directory of Open Access Journals (Sweden)

    Carlos M Opazo

    2014-07-01

    Full Text Available Copper is critical for the Central Nervous System (CNS development and function. In particular, different studies have shown the effect of copper at brain synapses, where it inhibits Long Term Potentation (LTP and receptor pharmacology. Paradoxically, according to recent studies copper is required for a normal LTP response. Copper is released at the synaptic cleft, where it blocks glutamate receptors, which explain its blocking effects on excitatory neurotransmission. Our results indicate that copper also enhances neurotransmission through the accumulation of PSD95 protein, which increase the levels of AMPA receptors located at the plasma membrane of the post-synaptic density. Thus, our findings represent a novel mechanism for the action of copper, which may have implications for the neurophysiology and neuropathology of the CNS. These data indicate that synaptic configuration is sensitive to transient changes in transition metal homeostasis. Our results suggest that copper increases GluA1 subunit levels of the AMPA receptor through the anchorage of AMPA receptors to the plasma membrane as a result of PSD-95 accumulation. Here, we will review the role of copper on neurotransmission of CNS neurons. In addition, we will discuss the potential mechanisms by which copper could modulate neuronal proteostasis (neuroproteostasis in the CNS with focus in the Ubiquitin Proteasome System, which is particularly relevant to neurological disorders such Alzheimer’s disease (AD where copper and protein dyshomeostasis may contribute to neurodegeneration. An understanding of these mechanisms may ultimately lead to the development of novel therapeutic approaches to control metal and synaptic alterations observed in AD patients.

  19. Use of copper radioisotopes in investigating disorders of copper metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Camakaris, J.; Voskoboinik, I.; Brooks, H.; Greenough, M. [University of Melbourne, Parkville, VIC (Australia). Department of Genetics; Smith, S. [Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW (Australia). Radiopharmaceuticals Division; Mercer, J. [Deakin University, Rusden Campus, Clayton, VIC (Australia). Centre of Cellular and Molecular Biology

    1998-12-31

    Full text: Copper is an essential trace element for life as a number of vital enzymes require it. Copper deficiency can lead to neurological disorders, osteoporosis and weakening of arteries. However Cu is also highly toxic and homeostatic mechanisms have evolved to maintain Cu at levels which satisfy requirements but do not cause toxicity. Toxicity is mediated by the oxidative capacity of Cu and its ability to generate toxic free radicals. There are several acquired and inherited diseases due to either Cu toxicity or Cu deficiency. The study of these diseases facilitates identification of genes and proteins involved in copper homeostasis, and this in turn will provide rational therapeutic approaches. Our studies have focused on Menkes disease in humans which is an inherited and usually lethal copper deficiency. Using copper radioisotopes {sup 64}Cu (t 1/2 = 12.8 hr) and {sup 67}Cu (t 1/2 = 61 hr) we have studied the protein which is mutated in Menkes disease. This is a transmembrane copper pump which is responsible for absorption of copper into the body and also functions to pump out excess Cu from cells when Cu is elevated. It is therefore a vital component of normal Cu homeostasis. We have provided the first biochemical evidence that the Menkes protein functions as a P-type ATPase Cu pump (Voskoboinik et al., FEBS Letters, in press) and these data will be discussed. The assay involved pumping of radiocopper into purified membrane vesicles. Furthermore we have transfected normal and mutant Menkes genes into cells and are carrying out structure-function studies. We are also studying the role of amyloid precursor protein (APP) as a Cu transport protein in order to determine how Cu regulates this protein and its cleavage products. These studies will provide vital information on the relationship between Cu and APP and processes which lead to Alzheimers disease

  20. Trace elements in human physiology and pathology. Copper.

    Science.gov (United States)

    Tapiero, H; Townsend, D M; Tew, K D

    2003-11-01

    Copper is a trace element, important for the function of many cellular enzymes. Copper ions can adopt distinct redox states oxidized Cu(II) or reduced (I), allowing the metal to play a pivotal role in cell physiology as a catalytic cofactor in the redox chemistry of enzymes, mitochondrial respiration, iron absorption, free radical scavenging and elastin cross-linking. If present in excess, free copper ions can cause damage to cellular components and a delicate balance between the uptake and efflux of copper ions determines the amount of cellular copper. In biological systems, copper homeostasis has been characterized at the molecular level. It is coordinated by several proteins such as glutathione, metallothionein, Cu-transporting P-type ATPases, Menkes and Wilson proteins and by cytoplasmic transport proteins called copper chaperones to ensure that it is delivered to specific subcellular compartments and thereby to copper-requiring proteins.

  1. A highly sensitive self assembled monolayer modified copper doped zinc oxide nanofiber interface for detection of Plasmodium falciparum histidine-rich protein-2: Targeted towards rapid, early diagnosis of malaria.

    Science.gov (United States)

    Brince Paul, K; Kumar, Sanni; Tripathy, Suryasnata; Vanjari, Siva Rama Krishna; Singh, Vikrant; Singh, Shiv Govind

    2016-06-15

    Rapid, ultrasensitive diagnostic/triaging kits for early detection of malarial parasites are critical for prevention of malarial epidemic, especially in developing and tropical countries. Unlike traditional microscopic diagnosis, these kits rely on the detection of antigens specific to malarial parasites. One such antigen which is routinely used in these diagnostic kits is Histidine-rich protein-2; a protein synthesized and released into the blood stream by the parasite Plasmodium falciparum. In this paper, we demonstrate an ultrasensitive nanobiosensor detection platform for Histidine-rich protein-2 having a limit of detection of attogram/ml. This nanobiosensor platform comprises of Mercaptopropylphosphonic acid functionalized copper doped zinc oxide nanofibers synthesized by electrospinning technique. Ultrasensitivity of attogram/ml can be attributed to the complimentary effects of Mercaptopropylphosphonic acid and copper doping in zinc oxide. Mercaptopropylphosphonic acid enhances the functional groups required for immobilizing antibody. Copper doping in zinc oxide not only increases the conductivity of the nanofibers but also pre-concentrates the target analyte onto the Mercaptopropylphosphonic acid treated nanofiber surface due to inherent electric field generated at the copper/zinc oxide heterojunction interface. The impedimetric detection response of copper-doped zinc oxide nanofiber modified electrode shows excellent sensitivity (28.5 kΩ/(gm/ml)/cm(2)) in the detection ranges of 10 ag/ml-10 µg/ml, and a detection limit of 6 attogram/ml. In addition, the proposed biosensor is highly selective to targeted HRP2 protein with a relative standard deviation of 1.9% in the presence of various interference of nonspecific molecules. To the best of our knowledge, this biosensor shows the lowest detection limit of malarial parasites reported in the literature spanning different nanomaterials and different detection mechanisms. Since the nanobiosensor platform is

  2. Blue and White Pot

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    Many recent archaeological studies have proven that the earliest blue and white porcelain was produced from the kiln in Gongxian County, Henan Province in the Tang Dynasty (618-907). It was an important variety of porcelain available for export then. The early blue and white porcelain in the Yuan Dynasty appeared dark and gray. During the reign of Zhizheng, clear blue and white porcelain was produced, indicating

  3. Cellular blue naevus

    Directory of Open Access Journals (Sweden)

    Mittal R

    2001-01-01

    Full Text Available A 31-year-old man had asymptomatic, stationary, 1.5X2 cm, shiny, smooth, dark blue nodule on dorsum of right hand since 12-14 years. In addition he had developed extensive eruption of yellow to orange papulonodular lesions on extensors of limbs and buttocks since one and half months. Investigations confirmed that yellow papules were xanthomatosis and he had associated diabetes mellitus and hyperlipidaemia. Biopsy of blue nodule confirmed the clinical diagnosis of cellular blue naevus. Cellular blue naevus is rare and its association with xanthomatosis and diabetes mellitus were interesting features of above patients which is being reported for its rarity.

  4. The role of the E2 copper binding domain in the cell biology of the amyloid precursor protein

    OpenAIRE

    Blanthorn-Hazell, Sophee

    2015-01-01

    Alzheimer’s disease is a neurodegenerative disorder characterised by the accumulation, in the brain, of neurotoxic amyloid beta-(Aβ) peptides. These peptides are generated from the amyloid precursor protein (APP) via the amyloidogenic proteolytic pathway which also leads to the formation of soluble APP beta (sAPPβ). Alternatively, APP can be cleaved by the non-amyloidogenic pathway in which an α-secretase activity cleaves the protein within the Aβ region generating soluble APP alpha (sAPPα). ...

  5. Evidence that translation reinitiation leads to a partially functional Menkes protein containing two copper-binding sites

    DEFF Research Database (Denmark)

    Paulsen, Marianne; Lund, Connie; Akram, Zarqa

    2006-01-01

    -dependent trafficking of the major part of endogenous and recombinant ATP7A(Delta ex3+ex4) proteins were similar to the wild-type ATP7A protein. Furthermore, the ATP7A(Delta ex3+ex4) cDNA was able to rescue a yeast strain lacking the homologous gene, CCC2. In summary, we propose that reinitiation of the NMD...

  6. Transcriptional response of the mussel Mytilus galloprovincialis (Lam. following exposure to heat stress and copper.

    Directory of Open Access Journals (Sweden)

    Alessandro Negri

    Full Text Available Global warming is a major factor that may affect biological organization, especially in marine ecosystems and in coastal areas that are particularly subject to anthropogenic pollution. We evaluated the effects of simultaneous changes in temperature and copper concentrations on lysosomal membrane stability (N-acetyl-hexosaminidase activity and malondialdehyde accumulation (MDA in the gill of the blue mussel Mytilus galloprovincialis (Lam.. Temperature and copper exerted additive effects on lysosomal membrane stability, exacerbating the toxic effects of metal cations present in non-physiological concentrations. Mussel lysosomal membrane stability is known to be positively related to scope for growth, indicating possible effects of increasing temperature on mussel populations in metal-polluted areas. To clarify the molecular response to environmental stressors, we used a cDNA microarray with 1,673 sequences to measure the relative transcript abundances in the gills of mussels exposed to copper (40 µg/L and a temperature gradient (16°C, 20°C, and 24°C. In animals exposed only to heat stress, hierarchical clustering of the microarray data revealed three main clusters, which were largely dominated by down-regulation of translation-related differentially expressed genes, drastic up-regulation of protein folding related genes, and genes involved in chitin metabolism. The response of mussels exposed to copper at 24°C was characterized by an opposite pattern of the genes involved in translation, most of which were up-regulated, as well as the down-regulation of genes encoding heat shock proteins and "microtubule-based movement" proteins. Our data provide novel information on the transcriptomic modulations in mussels facing temperature increases and high copper concentrations; these data highlight the risk of marine life exposed to toxic chemicals in the presence of temperature increases due to climate change.

  7. The copper metallome in prokaryotic cells.

    Science.gov (United States)

    Rensing, Christopher; McDevitt, Sylvia Franke

    2013-01-01

    As a trace element copper has an important role in cellular function like many other transition metals. Its ability to undergo redox changes [Cu(I) ↔ Cu(II)] makes copper an ideal cofactor in enzymes catalyzing electron transfers. However, this redox change makes copper dangerous for a cell since it is able to be involved in Fenton-like reactions creating reactive oxygen species (ROS). Cu(I) also is a strong soft metal and can attack and destroy iron-sulfur clusters thereby releasing iron which can in turn cause oxidative stress. Therefore, copper homeostasis has to be highly balanced to ensure proper cellular function while avoiding cell damage.Throughout evolution bacteria and archaea have developed a highly regulated balance in copper metabolism. While for many prokaryotes copper uptake seems to be unspecific, others have developed highly sophisticated uptake mechanisms to ensure the availability of sufficient amounts of copper. Within the cytoplasm copper is sequestered by various proteins and molecules, including specific copper chaperones, to prevent cellular damage. Copper-containing proteins are usually located in the cytoplasmic membrane with the catalytic domain facing the periplasm, in the periplasm of Gram-negative bacteria, or they are secreted, limiting the necessity of copper to accumulate in the cytoplasm. To prevent cellular damage due to excess copper, bacteria and archaea have developed various copper detoxification strategies. In this chapter we attempt to give an overview of the mechanisms employed by bacteria and archaea to handle copper and the importance of the metal for cellular function as well as in the global nutrient cycle.

  8. T versus D in the MTCXXC motif of copper transport proteins plays a role in directional metal transport.

    Science.gov (United States)

    Niemiec, Moritz S; Dingeldein, Artur P G; Wittung-Stafshede, Pernilla

    2014-08-01

    To avoid toxicity and control levels of metal ions, organisms have developed specific metal transport systems. In humans, the cytoplasmic Cu chaperone Atox1 delivers Cu to metal-binding domains of ATP7A/B in the Golgi, for incorporation into Cu-dependent proteins. The Cu-binding motif in Atox1, as well as in target Cu-binding domains of ATP7A/B, consists of a MX1CXXC motif where X1 = T. The same motif, with X1 = D, is found in metal-binding domains of bacterial zinc transporters, such as ZntA. The Asp is proposed to stabilize divalent over monovalent metals in the binding site, although metal selectivity in vivo appears predominantly governed by protein-protein interactions. To probe the role of T versus D at the X1 position for Cu transfer in vitro, we created MDCXXC variants of Atox1 and the fourth metal-binding domain of ATP7B, WD4. We find that the mutants bind Cu like the wild-type proteins, but when mixed, in contrast to the wild-type pair, the mutant pair favors Cu-dependent hetero-dimers over directional Cu transport from Atox1 to WD4. Notably, both wild-type and mutant proteins can bind Zn in the absence of competing reducing agents. In presence of zinc, hetero-complexes are strongly favored for both protein pairs. We propose that T is conserved in this motif of Cu-transport proteins to promote directional metal transfer toward ATP7B, without formation of energetic sinks. The ability of both Atox1 and WD4 to bind zinc ions may not be a problem in vivo due to the presence of specific transport chains for Cu and Zn ions.

  9. Feeling blue? Blue phosphors for OLEDs

    Directory of Open Access Journals (Sweden)

    Hungshin Fu

    2011-10-01

    Full Text Available Research on organic light emitting diodes (OLEDs has been revitalized, partly due to the debut of the OLED TV by SONY in 2008. While there is still plenty of room for improvement in efficiency, cost-effectiveness and longevity, it is timely to report on the advances of light emitting materials, the core of OLEDs, and their future perspectives. The focus of this account is primarily to chronicle the blue phosphors developed in our laboratory. Special attention is paid to the design strategy, synthetic novelty, and their OLED performance. The report also underscores the importance of the interplay between chemistry and photophysics en route to true-blue phosphors.

  10. Mixed ligand copper(II) dicarboxylate complexes: the role of co-ligand hydrophobicity in DNA binding, double-strand DNA cleavage, protein binding and cytotoxicity.

    Science.gov (United States)

    Loganathan, Rangasamy; Ramakrishnan, Sethu; Ganeshpandian, Mani; Bhuvanesh, Nattamai S P; Palaniandavar, Mallayan; Riyasdeen, Anvarbatcha; Akbarsha, Mohamad Abdulkadhar

    2015-06-14

    A few water soluble mixed ligand copper(ii) complexes of the type [Cu(bimda)(diimine)] , where bimda is N-benzyliminodiacetic acid and diimine is 2,2'-bipyridine (bpy, ) or 1,10-phenanthroline (phen, ) or 5,6-dimethyl-1,10-phenanthroline (5,6-dmp, ) or 3,4,7,8-tetramethyl-1,10-phenanthroline (3,4,7,8-tmp, ) and dipyrido[3,2-d: 2',3'-f]quinoxaline (dpq, ), have been successfully isolated and characterized by elemental analysis and other spectral techniques. The coordination geometry around copper(ii) in is described as distorted square based pyramidal while that in is described as square pyramidal. Absorption spectral titrations and competitive DNA binding studies reveal that the intrinsic DNA binding affinity of the complexes depends upon the diimine co-ligand, dpq () > 3,4,7,8-tmp () > 5,6-dmp () > phen () > bpy (). The phen and dpq co-ligands are involved in the π-stacking interaction with DNA base pairs while the 3,4,7,8-tmp/5,6-dmp and bpy co-ligands are involved in respectively hydrophobic and surface mode of binding with DNA. The small enhancement in the relative viscosity of DNA upon binding to supports the DNA binding modes proposed. Interestingly, and are selective in exhibiting a positive induced CD band (ICD) upon binding to DNA suggesting that they induce B to A conformational change. In contrast, and show CD responses which reveal their involvement in strong DNA binding. The complexes are unique in displaying prominent double-strand DNA cleavage while effects only single-strand DNA cleavage, and their ability to cleave DNA in the absence of an activator varies as > > > > . Also, all the complexes exhibit oxidative double-strand DNA cleavage activity in the presence of ascorbic acid, which varies as > > > > . The ability of the complexes to bind and cleave the protein BSA varies in the order > > > > . Interestingly, and cleave the protein non-specifically in the presence of H2O2 as an activator suggesting that they can act also as chemical proteases

  11. Copper at synapse: Release, binding and modulation of neurotransmission.

    Science.gov (United States)

    D'Ambrosi, Nadia; Rossi, Luisa

    2015-11-01

    Over the last decade, a piece of the research studying copper role in biological systems was devoted to unravelling a still elusive, but extremely intriguing, aspect that is the involvement of copper in synaptic function. These studies were prompted to provide a rationale to the finding that copper is released in the synaptic cleft upon depolarization. The copper pump ATP7A, which mutations are responsible for diseases with a prominent neurodegenerative component, seems to play a pivotal role in the release of copper at synapses. Furthermore, it was found that, when in the synaptic cleft, copper can control, directly or indirectly, the activity of the neurotransmitter receptors (NMDA, AMPA, GABA, P2X receptors), thus affecting excitability. In turn, neurotransmission can affect copper trafficking and delivery in neuronal cells. Furthermore, it was reported that copper can also modulate synaptic vesicles trafficking and the interaction between proteins of the secretory pathways. Interestingly, proteins with a still unclear role in neuronal system though associated with the pathogenesis of neurodegenerative diseases (the amyloid precursor protein, APP, the prion protein, PrP, α-synuclein, α-syn) show copper-binding domains. They may act as copper buffer at synapses and participate in the interplay between copper and the neurotransmitters receptors. Given that copper dysmetabolism occurs in several diseases affecting central and peripheral nervous system, the findings on the contribution of copper in synaptic transmission, beside its more consolidate role as a neuronal enzymes cofactor, may open new insights for therapy interventions.

  12. Overexpression of alpha-synuclein at non-toxic levels increases dopaminergic cell death induced by copper exposure via modulation of protein degradation pathways.

    Science.gov (United States)

    Anandhan, Annadurai; Rodriguez-Rocha, Humberto; Bohovych, Iryna; Griggs, Amy M; Zavala-Flores, Laura; Reyes-Reyes, Elsa M; Seravalli, Javier; Stanciu, Lia A; Lee, Jaekwon; Rochet, Jean-Christophe; Khalimonchuk, Oleh; Franco, Rodrigo

    2015-09-01

    Gene multiplications or point mutations in alpha (α)-synuclein are associated with familial and sporadic Parkinson's disease (PD). An increase in copper (Cu) levels has been reported in the cerebrospinal fluid and blood of PD patients, while occupational exposure to Cu has been suggested to augment the risk to develop PD. We aimed to elucidate the mechanisms by which α-synuclein and Cu regulate dopaminergic cell death. Short-term overexpression of wild type (WT) or mutant A53T α-synuclein had no toxic effect in human dopaminergic cells and primary midbrain cultures, but it exerted a synergistic effect on Cu-induced cell death. Cell death induced by Cu was potentiated by overexpression of the Cu transporter protein 1 (Ctr1) and depletion of intracellular glutathione (GSH) indicating that the toxic effects of Cu are linked to alterations in its intracellular homeostasis. Using the redox sensor roGFP, we demonstrated that Cu-induced oxidative stress was primarily localized in the cytosol and not in the mitochondria. However, α-synuclein overexpression had no effect on Cu-induced oxidative stress. WT or A53T α-synuclein overexpression exacerbated Cu toxicity in dopaminergic and yeast cells in the absence of α-synuclein aggregation. Cu increased autophagic flux and protein ubiquitination. Impairment of autophagy by overexpression of a dominant negative Atg5 form or inhibition of the ubiquitin/proteasome system (UPS) with MG132 enhanced Cu-induced cell death. However, only inhibition of the UPS stimulated the synergistic toxic effects of Cu and α-synuclein overexpression. Our results demonstrate that α-synuclein stimulates Cu toxicity in dopaminergic cells independent from its aggregation via modulation of protein degradation pathways.

  13. Advanced purification strategy for CueR, a cysteine containing copper(I) and DNA binding protein

    DEFF Research Database (Denmark)

    Balogh, Ria K.; Gyurcsik, Béla; Hunyadi-Gulyás, Éva

    2016-01-01

    . A detailed understanding of their function may be exploited in potential health, environmental and analytical applications. Members of the MerR protein family sense a broad range of mostly late transition and heavy metal ions through their cysteine thiolates. The air sensitivity of latter groups makes......Metal ion regulation is essential for living organisms. In prokaryotes metal ion dependent transcriptional factors, the so-called metalloregulatory proteins play a fundamental role in controlling the concentration of metal ions. These proteins recognize metal ions with an outstanding selectivity...... any affinity tag. Structure and functionality tests performed with mass spectrometry, circular dichroism spectroscopy and electrophoretic gel mobility shift assays approved the success of the purification procedure....

  14. Blue Ocean Thinking

    Science.gov (United States)

    Orem, Donna

    2016-01-01

    This article describes a concept called the "blue ocean thinking strategy," developed by W. Chan Kim and Renée Mauborgne, professors at INSEAD, an international graduate school of business in France. The "blue ocean" thinking strategy considers opportunities to create new markets for services, rather than focusing solely on…

  15. Blue Willow Story Plates

    Science.gov (United States)

    Fontes, Kris

    2009-01-01

    In the December 1997 issue of "SchoolArts" is a lesson titled "Blue Willow Story Plates" by Susan Striker. In this article, the author shares how she used this lesson with her middle-school students many times over the years. Here, she describes a Blue Willow plate painting project that her students made.

  16. From blue jeans to blue genes.

    Science.gov (United States)

    Boon, Laurence M; Vikkula, Miikka

    2009-03-01

    Cutaneous venous anomalies are common. They are blue and vary in size, number, and location and account for most consultations at specialized interdisciplinary clinics for vascular anomalies. Venous lesions are clinically important because they cause pain, dysfunction, destruction of adjacent tissues, and esthetic concern. Only resection and sclerotherapy are helpful, although not always curative. Understanding etiopathogenesis could help design animal models and develop novel therapeutic approaches. John B. Mulliken, MD, envisioned a project to uncover the genetic basis of an inherited form of venous malformation in a large New England family. Recruitment of 2 young fellows resulted in a collaborative project that unraveled the searched-for gene and its mutation. This was an opening for a new era in vascular anomalies. Two blue genes' mutations were discovered, which account for most, if not all, of the inherited forms of venous anomalies, but other genes as well, for rheologically diverse lesions. Differential diagnosis and management has improved, and animal models are being made. This was achieved through the help of Dr Mulliken, who inspired 2 young investigators in blue jeans to find 2 blue genes.

  17. Insertion of beta-alanine in model peptides for copper binding to His96 and His111 of the human prion protein.

    Science.gov (United States)

    Rivillas-Acevedo, Lina; Maciel-Barón, Luis; García, Javier E; Juaristi, Eusebio; Quintanar, Liliana

    2013-09-01

    The prion protein coordinates copper with high affinity in the regions encompassing residues 92-99 (GGGTHSQW) and 106-115 (KTNMKHMAGA). Cu(II) binding to these sites involves the coordination of the His96/His111 imidazole ring and backbone deprotonated amides that precede the His residue. Such a coordination arrangement involves the formation of hexa- and penta-membered cycles that provide further stabilization of the metal-peptide complex. The purpose of the present study is to introduce a methylene group in the peptide backbone, to evaluate the impact of increasing the size of these cycles in Cu(II) binding. Thus, a β-alanine residue was inserted at different positions preceding the His residue in these prion fragments, and their Cu(II) coordination properties were assessed by UV-Visible absorption, circular dichroism, and electron paramagnetic resonance. Spectroscopic data show that the insertion of a methylene group leads to a completely different Cu(II) coordination that involves the His96/His111 imidazole ring and nitrogen or oxygen atoms provided by the peptide backbone towards the C-terminal. This study clearly shows that two main factors determine the nature of Cu(II)-peptide complexes involving an anchoring His residue and deprotonated amides from the backbone chain: i) the stabilization of Cu(II)-peptide complexes due to the formation of cyclic structures (i.e. chelate effect) and ii) the nature of the residues associated to the deprotonated amide groups that participate in metal ion coordination.

  18. Copper homeostasis in Drosophila by complex interplay of import, storage and behavioral avoidance

    OpenAIRE

    Balamurugan, Kuppusamy; Egli, Dieter; Hua, Haiqing; Rajaram, Rama; Seisenbacher, Gerhard; Georgiev, Oleg; Schaffner, Walter

    2007-01-01

    Copper is an essential but potentially toxic trace element. In Drosophila, the metal-responsive transcription factor (MTF-1) plays a dual role in copper homeostasis: at limiting copper concentrations, it induces the Ctr1B copper importer gene, whereas at high copper concentrations, it mainly induces the metallothionein genes. Here we find that, despite the downregulation of the Ctr1B gene at high copper concentrations, the protein persists on the plasma membrane of intestinal cells for many h...

  19. Copper proteomes, phylogenetics and evolution.

    Science.gov (United States)

    Decaria, Leonardo; Bertini, Ivano; Williams, Robert J P

    2011-01-01

    This paper is a continuation of our study of the connection between the changing environment and the changing use of particular elements in organisms in the course of their combined evolution (Decaria, Bertini and Williams, Metallomics, 2010, 2, 706). Here we treat the changes in copper proteins in historically the same increasingly oxidising environmental conditions. The study is a bioinformatic analysis of the types and the numbers of copper domains of proteins from 435 DNA sequences of a wide range of organisms available in NCBI, using the method developed by Andreini, Bertini and Rosato in Accounts of Chemical Research 2009, 42, 1471. The copper domains of greatest interest are found predominantly in copper chaperones, homeostatic proteins and redox enzymes mainly used outside the cytoplasm which are in themselves somewhat diverse. The multiplicity of these proteins is strongly marked. The contrasting use of the iron and heme iron proteins in oxidations, mostly in the cytoplasm, is compared with them and with activity of zinc fingers during evolution. It is shown that evolution is a coordinated development of the chemistry of elements with use of novel and multiple copies of their proteins as their availability rises in the environment.

  20. Excretion of laccase by sycamore (Acer pseudoplatanus L.) cells. Effects of a copper deficiency.

    Science.gov (United States)

    Bligny, R; Gaillard, J; Douce, R

    1986-07-15

    Copper-deprived sycamore (Acer pseudoplatanus) cells do not excrete molecules of active laccase in their culture medium. In the range of 2-100 micrograms of copper initially present per litre of nutrient solution, the total laccase activity measured in the cell suspensions at the end of the exponential phase of growth was closely proportional to the amount of added copper. However, copper-deprived cells excreted the laccase apoprotein (laccase without copper) at the same rate as copper-supplied cells excreted the active, copper-containing, laccase. When the culture medium was initially supplied with limiting amounts of copper, the active laccase was excreted until all copper molecules were metabolized. Thereafter, the laccase apoprotein was excreted. Consequently, at the end of the exponential phase of growth, the cell supernatants contained a mixture of apoprotein and copper-containing laccase. After purification and concentration, this mixture of copper-containing laccase (blue) and laccase apoprotein (slightly yellow) showed a yellow-green colour. Under copper-limiting culture conditions an equivalent decrease of Type 1, Type 2 and Type 3 Cu2+ was observed. Addition of copper to copper-deficient enzyme solutions does not result in a recovery of the enzyme activity. However, when added to copper-deficient sycamore-cell suspensions, copper induced a recovery of the excretion of active enzyme, at a normal rate, within about 10 h. The first molecules of active laccase were excreted after 3-4 h.

  1. 以双(2-二苯基磷苯基)醚为配体的蓝色磷光铜(Ⅰ)配合物的合成及光电特性研究%Synthesis and Photoelectrical Properties of Blue Phosphorescent Copper (Ⅰ) Complex with Bis-[2-(diphenylphosphino) phenyl]-ether Ligand

    Institute of Scientific and Technical Information of China (English)

    屈丽桃; 许慧侠; 郝玉英; 李云飞; 任静琨; 王华; 许并社

    2012-01-01

    合成了一种新型的室温天蓝色磷光发射材料双(2-二苯基磷苯基)醚碘合铜(Ⅰ)([(POP)CuⅠ]2)配合物.通过红外光谱、X-射线单晶衍射确定其分子结构,并对其光电特性进行了详细研究.结果表明:[(POP)CuⅠ]2为二聚体结构,主要吸收峰为227,268,291 nm,最大发射峰为475 nm,光学带隙为2.93 eV.以[(POP) CuⅠ]2作为客体掺杂在主体CBP中作为发光层,制备了结构为ITO/NPB (30 nm)/CBP:[(POP) CuⅠ]2(30 nm,8%)/BAlq(10 nm)/Alq3(30 nm)/LiF(1 nm)/Al(200 nm)的器件,其电致发光峰为476 nm,最大亮度为9 539 cd/m2,最大电流效率为1.9 cd/A.%A new copper(I) complex of [ (POP)CuI]2[ POP: bis-[2-(diphenyl phosphino)phenyl] ether] with blue emission was designed and synthesized. The molecular structure and photophysical properties of [ ( POP) Cul]2 were investigated by FT-IR spectra, X-ray single crystal diffraction, UV-Vis absorption, emission spectra and cyclic voltammetry. The results indicate that the UV-Vis absorption peaks of [ (POP)Cul]2 are located at 227, 268 and 291 nm. The blue light can be observed with a peak at 475 nm in the solid state. The HOMO, LUMO energy levels and optical gap are -6.40, -3.47 and 2.93 eV, respectively. The devices of ITO/NPB(30 nm)/CBP:[(POP)CuI]2 (30 nm, 8%)/BAlq(10 nm)/Alq3(30 nm)/LiF(l nm) /Al(200 nm) were fabricated by doping [(POP)CuI]2 into CBP as emitting layer with emission peak at 476 nm and maximum luminance, current efficiency of 9 539 cd/m2, 1.9 cd/A.

  2. 铜离子转运蛋白家族与肺癌顺铂耐药的研究进展%Research progress on copper ion transport protein family and cisplatin drug resistance in lung cancer

    Institute of Scientific and Technical Information of China (English)

    阳甜; 陈天君; 陈明伟

    2012-01-01

    铂类药作为化疗一种关键药之一,被广泛用于治疗各种恶性肿瘤,如卵巢、膀胱、头颈部肿瘤及肺癌.但铂类耐药的发生限制了化疗反应,影响了患者的预后.目前在铂类耐药的机制方面已经有一些重要的发展,其中之一是肿瘤铂类耐药与细胞内浓度的蓄积之间的相关性,摄入的减少和泵出过多均可减少药物在细胞内的聚积,导致耐药.但是具体耐药机制尚不清楚.铜离子动态平衡是由铜离子转运蛋白及其分子伴侣来维持.铜离子转运蛋白家族包括铜离子转运蛋白和铜离子转运磷酸化ATP酶.本文将就铜离子转运蛋白家族与肺癌顺铂耐药作一综述.%Cisplatin is one of the most important chemotherapeutic agents,commonly used for treatment of various cancers including ovary,endometrial,lung and gastric cancer.The secondary drugresistance,however,limits the efficacy of chemotherapy and consequently compromises the prognosis of patients.Recently,there have been some important developments in the understanding of mechanisms of tumor resistance to cisplatin.One of them is concerning the association between the tumor resistance to platinum drugs and the reduced intracellular accumulation owing to impaired drug intake and enhanced outward transport.However,mechanisms for transporting platinum drugs were not known until recently studies have shown that copper transporters may be involved in the transport of platinum-based anticancer drugs.Body copper homeostasis is maintained by a group of proteins including copper transporters and chaperones.Copper transporters include copper transporter 1 and copper-transporting P-type adenosine triphosphatase.This paper will state copper ion transport protein family and cisplatin drug resistance in lung cancer.

  3. Blue ocean strategy.

    Science.gov (United States)

    Kim, W Chan; Mauborgne, Renée

    2004-10-01

    Despite a long-term decline in the circus industry, Cirque du Soleil profitably increased revenue 22-fold over the last ten years by reinventing the circus. Rather than competing within the confines of the existing industry or trying to steal customers from rivals, Cirque developed uncontested market space that made the competition irrelevant. Cirque created what the authors call a blue ocean, a previously unknown market space. In blue oceans, demand is created rather than fought over. There is ample opportunity for growth that is both profitable and rapid. In red oceans--that is, in all the industries already existing--companies compete by grabbing for a greater share of limited demand. As the market space gets more crowded, prospects for profits and growth decline. Products turn into commodities, and increasing competition turns the water bloody. There are two ways to create blue oceans. One is to launch completely new industries, as eBay did with online auctions. But it's much more common for a blue ocean to be created from within a red ocean when a company expands the boundaries of an existing industry. In studying more than 150 blue ocean creations in over 30 industries, the authors observed that the traditional units of strategic analysis--company and industry--are of limited use in explaining how and why blue oceans are created. The most appropriate unit of analysis is the strategic move, the set of managerial actions and decisions involved in making a major market-creating business offering. Creating blue oceans builds brands. So powerful is blue ocean strategy, in fact, that a blue ocean strategic move can create brand equity that lasts for decades.

  4. Le blue-jean

    OpenAIRE

    Miller, Daniel

    2012-01-01

    Le Blue-jean: pourquoi la technologie vient en dernier. La plupart des personnes pensent que la technique (ou la technologie) correspond à ce qui vient en amont du produit. Dans cet article, Daniel Miller s’intéresse plutôt à des cas dans lesquels l’ordre de la séquence est renversé et où le produit précède, ou initie, en quelque sorte, la technique. L’auteur commence par décrire les techniques d’usure artificielle des blue jeans  : une technique qui vise à copier les effets du port des blue ...

  5. FROM BLUE JEANS TO BLUE GENES

    OpenAIRE

    Boon, Laurence M.; Vikkula, Miikka

    2009-01-01

    Cutaneous venous anomalies are common. They are blue in color and vary in size, number and location, and account for the majority of consultations at specialized interdisciplinary clinics for vascular anomalies. Venous lesions are clinically important as they cause pain, dysfunction, destruction of adjacent tissues and esthetic concern. Only resection and sclerotherapy are helpful, although not always curative. Understanding etiopathogenesis could help design animal models and develop novel t...

  6. From red to blue to far-red in Lhca4 : How does the protein modulate the spectral properties of the pigments?

    NARCIS (Netherlands)

    Wientjes, Emilie; Roest, Gemma; Croce, Roberta

    2012-01-01

    The first event of photosynthesis is the harvesting of solar energy by a large array of pigments. These pigments are coordinated to proteins that organize them to assure efficient excitation energy transfer. The protein plays an essential role in tuning the spectroscopic properties of the pigments,

  7. Type 1 copper site synthetic model complexes with increased redox potentials.

    Science.gov (United States)

    Yang, Lei; Tolman, William B

    2012-02-01

    Reactions of NaSCPh(3) with (R(3)tacn)Cu(OTf)(2) (R is Me, iPr; tacn is 1,4,7-triazacyclononane; OTf is CF(3)SO(3)(-)) yield blue complexes identified as ((R(3)tacn)CuSCPh(3))(OTf) on the basis of UV-vis, resonance Raman, and electron paramagnetic resonance (EPR) spectroscopy and electrospray ionization mass spectrometry. These complexes exhibit spectroscopic properties typical of type 1 copper sites in proteins, including diagnostic Sπ → Cu(d(x(2)-y(2))) ligand-to-metal charge transfer transitions at approximately 610-630 nm and small A(||) values in EPR spectra of less than 100 × 10(-4) cm(-1). Cyclic voltammetry experiments revealed redox potentials for the complexes similar to those of several low-potential type 1 copper proteins (e.g., azurin, stellacyanin) and approximately 0.5 V higher than those of previously reported model compounds. Thus, the new complexes mimic key aspects of both the structure and the function of type 1 copper sites.

  8. Formation of Copper-Salivary Component Complexes and Its Effect on Sensory Perception

    OpenAIRE

    Hong, Jae Hee

    2006-01-01

    Copper in drinking water elicits a persisting bitter, metallic, or astringent taste. Characteristics and perception mechanisms of copper sensation have not been fully understood. Saliva is assumed to influence copper sensations via binding of salivary electrolytes or proteins with copper. The interaction between salivary components and copper is thought to influence sensory perception by affecting volatility of aroma compounds, de-lubricating salivary proteins, and by controlling solubil...

  9. Blue Ribbon Panel Report

    Science.gov (United States)

    An NCI Cancer Currents blog by the NCI acting director thanking the cancer community for contributing to the Cancer Moonshot Blue Ribbon Panel report, which was presented to the National Cancer Advisory Board on September 7.

  10. New York Blue

    Data.gov (United States)

    Federal Laboratory Consortium — New York Blue is used cooperatively by the Laboratory and Stony Brook University as part of the New York Center for Computation Sciences. Ranked as the 28th fastest...

  11. Methylene blue test

    Science.gov (United States)

    Methemoglobinemia - methylene blue test ... No special preparation is required for this test. ... which are genetic (problem with your genes). This test is used to tell the difference between methemoglobinemia ...

  12. The Role of Copper Chaperone Atox1 in Coupling Redox Homeostasis to Intracellular Copper Distribution

    Science.gov (United States)

    Hatori, Yuta; Lutsenko, Svetlana

    2016-01-01

    Human antioxidant protein 1 (Atox1) is a small cytosolic protein with an essential role in copper homeostasis. Atox1 functions as a copper carrier facilitating copper transfer to the secretory pathway. This process is required for activation of copper dependent enzymes involved in neurotransmitter biosynthesis, iron efflux, neovascularization, wound healing, and regulation of blood pressure. Recently, new cellular roles for Atox1 have emerged. Changing levels of Atox1 were shown to modulate response to cancer therapies, contribute to inflammatory response, and protect cells against various oxidative stresses. It has also become apparent that the activity of Atox1 is tightly linked to the cellular redox status. In this review, we summarize biochemical information related to a dual role of Atox1 as a copper chaperone and an antioxidant. We discuss how these two activities could be linked and contribute to establishing the intracellular copper balance and functional identity of cells during differentiation. PMID:27472369

  13. Copper binding triggers compaction in N-terminal tail of human copper pump ATP7B.

    Science.gov (United States)

    Mondol, Tanumoy; Åden, Jörgen; Wittung-Stafshede, Pernilla

    2016-02-12

    Protein conformational changes are fundamental to biological reactions. For copper ion transport, the multi-domain protein ATP7B in the Golgi network receives copper from the cytoplasmic copper chaperone Atox1 and, with energy from ATP hydrolysis, moves the metal to the lumen for loading of copper-dependent enzymes. Although anticipated, conformational changes involved in ATP7B's functional cycle remain elusive. Using spectroscopic methods we here demonstrate that the four most N-terminal metal-binding domains in ATP7B, upon stoichiometric copper addition, adopt a more compact arrangement which has a higher thermal stability than in the absence of copper. In contrast to previous reports, no stable complex was found in solution between the metal-binding domains and the nucleotide-binding domain of ATP7B. Metal-dependent movement of the first four metal-binding domains in ATP7B may be a trigger that initiates the overall catalytic cycle.

  14. Natural polyphenols may ameliorate damage induced by copper overload.

    Science.gov (United States)

    Arnal, Nathalie; Tacconi de Alaniz, María J; Marra, Carlos Alberto

    2012-02-01

    The effect of the simultaneous exposure to transition metals and natural antioxidants frequently present in food is a question that needs further investigation. We aimed to explore the possible use of the natural polyphenols caffeic acid (CA), resveratrol (RES) and curcumin (CUR) to prevent damages induced by copper-overload on cellular molecules in HepG2 and A-549 human cells in culture. Exposure to 100μM/24h copper (Cu) caused extensive pro-oxidative damage evidenced by increased TBARS, protein carbonyls and nitrite productions in both cell types. Damage was aggravated by simultaneous incubation with 100μM of CA or RES, and it was also reflected in a decrease on cellular viability explored by trypan blue dye exclusion test and LDH leakage. Co-incubation with CUR produced opposite effects demonstrating a protective action which restored the level of biomarkers and cellular viability almost to control values. Thus, while CA and RES might aggravate the oxidative/nitrative damage of Cu, CUR should be considered as a putative protective agent. These results could stimulate further research on the possible use of natural polyphenols as neutralizing substances against the transition metal over-exposure in specific populations such as professional agrochemical sprayers and women using Cu-intrauterine devices.

  15. Copper and conquer: copper complexes of di-2-pyridylketone thiosemicarbazones as novel anti-cancer therapeutics.

    Science.gov (United States)

    Park, Kyung Chan; Fouani, Leyla; Jansson, Patric J; Wooi, Danson; Sahni, Sumit; Lane, Darius J R; Palanimuthu, Duraippandi; Lok, Hiu Chuen; Kovačević, Zaklina; Huang, Michael L H; Kalinowski, Danuta S; Richardson, Des R

    2016-09-01

    Copper is an essential trace metal required by organisms to perform a number of important biological processes. Copper readily cycles between its reduced Cu(i) and oxidised Cu(ii) states, which makes it redox active in biological systems. This redox-cycling propensity is vital for copper to act as a catalytic co-factor in enzymes. While copper is essential for normal physiology, enhanced copper levels in tumours leads to cancer progression. In particular, the stimulatory effect of copper on angiogenesis has been established in the last several decades. Additionally, it has been demonstrated that copper affects tumour growth and promotes metastasis. Based on the effects of copper on cancer progression, chelators that bind copper have been developed as anti-cancer agents. In fact, a novel class of thiosemicarbazone compounds, namely the di-2-pyridylketone thiosemicarbazones that bind copper, have shown great promise in terms of their anti-cancer activity. These agents have a unique mechanism of action, in which they form redox-active complexes with copper in the lysosomes of cancer cells. Furthermore, these agents are able to overcome P-glycoprotein (P-gp) mediated multi-drug resistance (MDR) and act as potent anti-oncogenic agents through their ability to up-regulate the metastasis suppressor protein, N-myc downstream regulated gene-1 (NDRG1). This review provides an overview of the metabolism and regulation of copper in normal physiology, followed by a discussion of the dysregulation of copper homeostasis in cancer and the effects of copper on cancer progression. Finally, recent advances in our understanding of the mechanisms of action of anti-cancer agents targeting copper are discussed.

  16. Molecular responses of mouse macrophages to copper and copper oxide nanoparticles inferred from proteomic analyses.

    Science.gov (United States)

    Triboulet, Sarah; Aude-Garcia, Catherine; Carrière, Marie; Diemer, Hélène; Proamer, Fabienne; Habert, Aurélie; Chevallet, Mireille; Collin-Faure, Véronique; Strub, Jean-Marc; Hanau, Daniel; Van Dorsselaer, Alain; Herlin-Boime, Nathalie; Rabilloud, Thierry

    2013-11-01

    The molecular responses of macrophages to copper-based nanoparticles have been investigated via a combination of proteomic and biochemical approaches, using the RAW264.7 cell line as a model. Both metallic copper and copper oxide nanoparticles have been tested, with copper ion and zirconium oxide nanoparticles used as controls. Proteomic analysis highlighted changes in proteins implicated in oxidative stress responses (superoxide dismutases and peroxiredoxins), glutathione biosynthesis, the actomyosin cytoskeleton, and mitochondrial proteins (especially oxidative phosphorylation complex subunits). Validation studies employing functional analyses showed that the increases in glutathione biosynthesis and in mitochondrial complexes observed in the proteomic screen were critical to cell survival upon stress with copper-based nanoparticles; pharmacological inhibition of these two pathways enhanced cell vulnerability to copper-based nanoparticles, but not to copper ions. Furthermore, functional analyses using primary macrophages derived from bone marrow showed a decrease in reduced glutathione levels, a decrease in the mitochondrial transmembrane potential, and inhibition of phagocytosis and of lipopolysaccharide-induced nitric oxide production. However, only a fraction of these effects could be obtained with copper ions. In conclusion, this study showed that macrophage functions are significantly altered by copper-based nanoparticles. Also highlighted are the cellular pathways modulated by cells for survival and the exemplified cross-toxicities that can occur between copper-based nanoparticles and pharmacological agents.

  17. Molecular Responses of Mouse Macrophages to Copper and Copper Oxide Nanoparticles Inferred from Proteomic Analyses*

    Science.gov (United States)

    Triboulet, Sarah; Aude-Garcia, Catherine; Carrière, Marie; Diemer, Hélène; Proamer, Fabienne; Habert, Aurélie; Chevallet, Mireille; Collin-Faure, Véronique; Strub, Jean-Marc; Hanau, Daniel; Van Dorsselaer, Alain; Herlin-Boime, Nathalie; Rabilloud, Thierry

    2013-01-01

    The molecular responses of macrophages to copper-based nanoparticles have been investigated via a combination of proteomic and biochemical approaches, using the RAW264.7 cell line as a model. Both metallic copper and copper oxide nanoparticles have been tested, with copper ion and zirconium oxide nanoparticles used as controls. Proteomic analysis highlighted changes in proteins implicated in oxidative stress responses (superoxide dismutases and peroxiredoxins), glutathione biosynthesis, the actomyosin cytoskeleton, and mitochondrial proteins (especially oxidative phosphorylation complex subunits). Validation studies employing functional analyses showed that the increases in glutathione biosynthesis and in mitochondrial complexes observed in the proteomic screen were critical to cell survival upon stress with copper-based nanoparticles; pharmacological inhibition of these two pathways enhanced cell vulnerability to copper-based nanoparticles, but not to copper ions. Furthermore, functional analyses using primary macrophages derived from bone marrow showed a decrease in reduced glutathione levels, a decrease in the mitochondrial transmembrane potential, and inhibition of phagocytosis and of lipopolysaccharide-induced nitric oxide production. However, only a fraction of these effects could be obtained with copper ions. In conclusion, this study showed that macrophage functions are significantly altered by copper-based nanoparticles. Also highlighted are the cellular pathways modulated by cells for survival and the exemplified cross-toxicities that can occur between copper-based nanoparticles and pharmacological agents. PMID:23882024

  18. Hydrogen Bonds Dictate the Coordination Geometry of Copper: Characterization of a Square-Planar Copper(I) Complex.

    Science.gov (United States)

    Dahl, Eric W; Szymczak, Nathaniel K

    2016-02-24

    6,6''-Bis(2,4,6-trimethylanilido)terpyridine (H2Tpy(NMes)) was prepared as a rigid, tridentate pincer ligand containing pendent anilines as hydrogen bond donor groups in the secondary coordination sphere. The coordination geometry of (H2 Tpy(NMes))copper(I)-halide (Cl, Br and I) complexes is dictated by the strength of the NH-halide hydrogen bond. The Cu(I)Cl and Cu(II)Cl complexes are nearly isostructural, the former presenting a highly unusual square-planar geometry about Cu(I) . The geometric constraints provided by secondary interactions are reminiscent of blue copper proteins where a constrained geometry, or entatic state, allows for extremely rapid Cu(I)/Cu(II) electron-transfer self-exchange rates. Cu(H2 Tpy(NMes))Cl shows similar fast electron transfer (≈10(5)  m(-1)  s(-1)) which is the same order of magnitude as biological systems.

  19. The histidine composition of the amyloid-β domain, but not the E1 copper binding domain, modulates β-secretase processing of amyloid-β protein precursor in Alzheimer's disease.

    Science.gov (United States)

    Gough, Mallory; Blanthorn-Hazell, Sophee; Parkin, Edward T

    2015-01-01

    Amyloid-β protein precursor (AβPP) proteolysis by β- and γ-secretases generates neurotoxic amyloid-β (Aβ)-peptides in Alzheimer's disease (AD). We have investigated the role of histidine residues within the extracellular E1 copper binding and Aβ domains of AβPP in its proteolysis. By stably expressing histidine to alanine AβPP mutant constructs in SH-SY5Y cells, we show that mutations in the E1 copper binding domain had no impact on α- or β-secretase processing. Mutation of histidine 14 within the Aβ-domain specifically down-regulated β-secretase processing without impacting on non-amyloidogenic proteolysis. Understanding how histidine 14 participates in AβPP proteolysis may reveal new intervention points for AD treatments.

  20. 朊病毒蛋白prion与二价铜离子相互作用的研究进展%Research Progress in the Interaction of Prion Proteins and Copper (Ⅱ) Ions

    Institute of Scientific and Technical Information of China (English)

    练富林; 文祎; 黄培; 林东海

    2012-01-01

    Prion diseases or transmissible spongiform encephalopathies are a group of rare and fatal neurodegenerative disorders that can be sporadic, inherited, or acquired by infectious means. These include Creutzfeldt-Jacob disease, kuru, familial fatal insomnia in humans, scrapie in sheep and goats, and bovine spongiform encephalopathies in cattle. The diseases are associated with a conforma-tional conversion of the normal cellular, membrane-anchored prion protein ( PrP ) into an oligomeric, (3-sheet rich, proteinase-K resistant, infectious form termed PRP50. An enormous body of literature has been published in the last ten years concerning copper and prion protein. This present review attempts to look at the evidence for co-ordination, affinity and the physiology function of copper binding to PrP. The evidence with possible roles for PrP when bound to copper was connected here. No clear conclusions can be made from the available data,but it is clear from the present review that the aspects of copper association with PrP need to be re-investigated.%传染性海绵状脑病是一类致死性的中枢神经系统退行性疾病,其发病机制与prion蛋白构象的错误折叠相关.Prion蛋白对二价铜离子具有极强的选择性.文章综述了二价铜离子与prpc的结合模式、结合力以及铜离子在prion蛋白错误折叠过程中可能发挥的作用.

  1. Atypical cellular blue nevus or malignant blue nevus?*

    Science.gov (United States)

    Daltro, Luise Ribeiro; Yaegashi, Lygia Bertalha; Freitas, Rodrigo Abdalah; Fantini, Bruno de Carvalho; Souza, Cacilda da Silva

    2017-01-01

    Blue nevus is a benign melanocytic lesion whose most frequent variants are dendritic (common) blue nevus and cellular blue nevus. Atypical cellular blue nevus presents an intermediate histopathology between the typical and a rare variant of malignant blue nevus/melanoma arising in a cellular blue nevus. An 8-year-old child presented a pigmented lesion in the buttock since birth, but with progressive growth in the last two years. After surgical excision, histopathological examination revealed atypical cellular blue nevus. Presence of mitoses, ulceration, infiltration, cytological atypia or necrosis may occur in atypical cellular blue nevus, making it difficult to differentiate it from melanoma. The growth of blue nevus is unusual and considered of high-risk for malignancy, being an indicator for complete resection and periodic follow-up of these patients. PMID:28225968

  2. Spectroscopic analysis of the dark relaxation process of a photocycle in a sensor of blue light using FAD (BLUF) protein Slr1694 of the cyanobacterium Synechocystis sp. PCC6803.

    Science.gov (United States)

    Hasegawa, Koji; Masuda, Shinji; Ono, Taka-Aki

    2005-01-01

    Slr1694 is a BLUF (sensor of blue light using flavin adenine dinucleotide) protein and a putative photoreceptor in the cyanobacterium Synechocystis sp. PCC6803. Illumination of Slr1694 induced a signaling light state concurrent with a red shift in the UV-visible absorption of flavin, and formation of the bands from flavin and apo-protein in the light-minus-dark Fourier transform infrared (FTIR) difference spectrum. Replacement of Tyr8 with phenylalanine abolished these changes. The light state relaxed to the ground dark state, during which the FTIR bands decayed monophasically. These bands were classifiable into three groups according to their decay rates. The C4=O stretching bands of a flavin isoalloxazine ring had the highest decay rate, which corresponded to that of the absorption red shift. The result indicated that the hydrogen bonding at C4=O is responsible for the UV-visible red shift, consistent with the results of density functional calculation. All FTIR bands and the red shift decayed at the same slower rate in deuterated Slr1694. These results indicated that the dark relaxation from the light state is limited by proton transfer. In contrast, a constrained light state formed under dehydrated conditions decayed much more slowly with no deuteration effects. A photocycle mechanism involving the proton transfer was proposed.

  3. The Blue Collar Brain

    Directory of Open Access Journals (Sweden)

    Guy eVan Orden

    2012-06-01

    Full Text Available Much effort has gone into elucidating control of the body by the brain, less so the role of the body in controlling the brain. This essay develops the idea that the brain does a great deal of work in the service of behavior that is controlled by the body, a blue collar role compared to the white collar control exercised by the body. The argument that supports a blue collar role for the brain is also consistent with recent discoveries clarifying the white collar role of synergies across the body's tensegrity structure, and the evidence of critical phenomena in brain and behavior.

  4. A Blue Lagoon Function

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2007-01-01

    We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$.......We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$....

  5. Copper Products Capacity Expansion Stimulate the Copper Consumption

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>The dramatic growth of copper consumption in China can directly be seen from the expansion of copper products capacity.According to sta- tistics,in the past 4 years,the improvement on the balance of trade on copper bar,copper,and copper alloy and copper wire & cable has driven the growth of copper consumption a lot.

  6. Electrochemical and morphological characterisation of polyphenazine films on copper

    Energy Technology Data Exchange (ETDEWEB)

    Gouveia-Caridade, Carla; Romeiro, Andreia; Brett, Christopher M.A., E-mail: cbrett@ci.uc.pt

    2013-11-15

    The morphology of films of the phenazine polymers poly(neutral red) (PNR), poly(brilliant cresyl blue) (PBCB), poly(Nile blue A) (PNB) and poly(safranine T) (PST), formed by potential cycling electropolymerisation on copper electrodes, in order to reduce the corrosion rate of copper, has been examined by scanning electron microscopy (SEM). The copper surface was initially partially passivated in sodium oxalate, hydrogen carbonate or salicylate solution, in order to inhibit copper dissolution at potentials where phenazine monomer oxidation occurs, and to induce better polymer film adhesion. SEM images were also taken of partially passivated copper in order to throw light on the different morphology and anti-corrosive behaviour of the polyphenazine films. Analysis of the morphology of the polymer-coated copper with best anti-corrosive behaviour after 72 h immersion in 0.1 M KCl, Cu/hydrogen carbonate/PNB, showed that the surface is completely covered by closely packed crystals. By contrast, images of PST films on copper partially passivated in oxalate solution, that had the least protective behaviour, showed large amounts of insoluble corrosion products after only 4 h immersion in 0.1 M KCl.

  7. Antwerp Copper Plates

    DEFF Research Database (Denmark)

    Wadum, Jørgen

    1999-01-01

    In addition to presenting a short history of copper paintings, topics detail artists’ materials and techniques, as well as aspects of the copper industry, including mining, preparation and trade routes.......In addition to presenting a short history of copper paintings, topics detail artists’ materials and techniques, as well as aspects of the copper industry, including mining, preparation and trade routes....

  8. After Stroke, 'Blue' Light May Help Beat the Blues

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_163731.html After Stroke, 'Blue' Light May Help Beat the Blues Akin ... a danger for people recovering from a debilitating stroke. But new research suggests that tweaking a rehabilitation ...

  9. Plaque Type Blue Naevus

    Directory of Open Access Journals (Sweden)

    Sentamilselvi G

    1997-01-01

    Full Text Available A case of plaque type blue naevus was encountered in a Dermatology Clinic in Madras. The various clinical differential diagnoses are discussed, the hitopathological features described and the benign nature of the tumour stressed. The case is reported for its rarity and to create an awareness of this entity.

  10. Blue rubber bleb naevus

    Directory of Open Access Journals (Sweden)

    Mittal R

    1995-01-01

    Full Text Available A 35 year old female had multiple progressive painful, tender, soft, bluish compressible nodules with the feel of rubber nipples. There was no evidence of gastrointestinal haemangiomas or other systemic abnormalities. Histopathologically, cavernous haemangioma with prominent smooth muscle outline proved the clinical diagnosis of blue rubber bleb naevus. Only cutaneous lesions were seen in the patient.

  11. The "Blue Banana" Revisited

    NARCIS (Netherlands)

    Faludi, A.K.F.

    2015-01-01

    This essay is about the “Blue Banana”. Banana is the name given subsequently by others to a Dorsale européenne (European backbone) identified empirically by Roger Brunet. In a background study to the Communication of the European Commission ‘Europe 2000’, Klaus Kunzmann and Michael Wegener put forwa

  12. The Blue Denmark

    DEFF Research Database (Denmark)

    Hansen, Carsten Ørts; Sornn-Friese, Henrik

    This paper makes an important contribution to the discussion about knowledge based localised externalities in the context of shipping and the maritime sector in Denmark. In the paper we ask if there is a national, knowledge‐based maritime cluster configured around the shipowners in Denmark. This ...... talk about The Blue Denmark....

  13. Blue spectral inflation

    CERN Document Server

    Schunck, Franz E

    2008-01-01

    We reconsider the nonlinear second order Abel equation of Stewart and Lyth, which follows from a nonlinear second order slow-roll approximation. We find a new eigenvalue spectrum in the blue regime. Some of the discrete values of the spectral index n_s have consistent fits to the cumulative COBE data as well as to recent ground-base CMB experiments.

  14. Dark Blue II

    OpenAIRE

    2013-01-01

    Dark Blue II, high fired porcelain, decorated with cobalt chloride, woodfired with salt. 10,5 x 10,5 x 19 cm. Ferdigstilt: 2012. Innkjøpt til Collection of The American Museum of Ceramic Art, Pomona, California, USA.

  15. Formation of interacting spins on flavosemiquinone and tyrosine radical in photoreaction of a blue light sensor BLUF protein TePixD.

    Science.gov (United States)

    Nagai, Hiroko; Fukushima, Yoshimasa; Okajima, Koji; Ikeuchi, Masahiko; Mino, Hiroyuki

    2008-11-25

    Light-induced radicals were detected by electron paramagnetic resonance (EPR) and pulsed electron-nuclear double resonance (ENDOR) in the BLUF-domain protein TePixD of the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1. The illumination of TePixD at 5-200 K derived an EPR signal with a separation of 85 G between the main peaks around g = 2, showing a typical Pake's pattern of magnetic dipole-dipole interaction between two nearby radicals. Longer illumination induced an EPR signal at g = 2.0045, which was assigned as a neutral flavosemiquinone FADH(*). The FADH(*) formation occurred in parallel with a decrease in Pake's doublet. The Pake's doublet was not detected in a mutant TePixD protein in which a tyrosine residue was replaced with phenylalanine (Y8F protein). A pulsed ENDOR study suggested that the Pake's doublet had arisen from the interaction between a neutral flavosemiquinone radical and a neutral tyrosine radical, i.e., the FADH(*)-Y8(*) state. An EPR simulation of the Pake's doublet showed that the distance between FAD and Y8 is 2.2 A shorter than that calculated from the X-ray crystallography structure in the dark-adapted state, suggesting the modification of the protein conformation in the photoinduced FADH(*)-Y8(*) state. The Pake's doublet signal was detected by 10 K illumination in the sample which was immediately frozen after 273 K illumination, corresponding to the red-shifted state F(490). On the other hand, the signal was not detected in the sample which was incubated for 10 min at 273 K in the dark after 273 K illumination, corresponding to the dark-adapted state D(471). In the sample annealed at 160 K for 10 min after 160 K illumination, corresponding to the partially red-shifted state J(11), the Pake's doublet signal was detected by the 10 K illumination. On the basis of these observations, we concluded that the interaction with the FADH(*)-Y8(*) state occurred after the second photoexcitation of the photoinduced red

  16. Copper(II) enhances membrane-bound α-synuclein helix formation.

    Science.gov (United States)

    Lucas, Heather R; Lee, Jennifer C

    2011-03-01

    Interactions of copper and membranes with α-synuclein have been implicated in pathogenic mechanisms of Parkinson's disease, yet work examining both concurrently is scarce. We have examined the effect of copper(ii) on protein/vesicle binding and found that both the copper(ii) affinity and α-helical content are enhanced for the membrane-bound protein.

  17. Copper(II) enhances membrane-bound α-synuclein helix formation

    OpenAIRE

    Lucas, Heather R.; Lee, Jennifer C.

    2011-01-01

    Interactions of copper and membranes with α-synuclein have been implicated in pathogenic mechanisms of Parkinson’s disease, yet work examining both concurrently is scarce. We have examined the effect of copper(II) on protein/vesicle binding and found that both the copper(II) affinity and α-helical content are enhanced for the membrane-bound protein.

  18. Axial ligand modulation of the electronic structures of binuclear copper sites: analysis of paramagnetic 1H NMR spectra of Met160Gln Cu(A).

    Science.gov (United States)

    Fernández, C O; Cricco, J A; Slutter, C E; Richards, J H; Gray, H B; Vila, A J

    2001-11-28

    Cu(A) is an electron-transfer copper center present in heme-copper oxidases and N2O reductases. The center is a binuclear unit, with two cysteine ligands bridging the metal ions and two terminal histidine residues. A Met residue and a peptide carbonyl group are located on opposite sides of the Cu2S2 plane; these weaker ligands are fully conserved in all known Cu(A) sites. The Met160Gln mutant of the soluble subunit II of Thermus thermophilus ba3 oxidase has been studied by NMR spectroscopy. In its oxidized form, the binuclear copper is a fully delocalized mixed-valence pair, as are all natural Cu(A) centers. The faster nuclear relaxation in this mutant suggests that a low-lying excited state has shifted to higher energies compared to that of the wild-type protein. The introduction of the Gln residue alters the coordination mode of His114 but does not affect His157, thereby confirming the proposal that the axial ligand-to-copper distances influence the copper-His interactions (Robinson, H.; Ang, M. C.; Gao, Y. G.; Hay, M. T.; Lu, Y.; Wang, A. H. Biochemistry 1999, 38, 5677). Changes in the hyperfine coupling constants of the Cys beta-CH2 groups are attributed to minor geometrical changes that affect the Cu-S-C(beta)-H(beta) dihedral angles. These changes, in addition, shift the thermally accessible excited states, thus influencing the spectral position of the Cys beta-CH2 resonances. The Cu-Cys bonds are not substantially altered by the Cu-Gln160 interaction, in contrast to the situation found in the evolutionarily related blue copper proteins. It is possible that regulatory subunits in the mitochondrial oxidases fix the relative positions of thermally accessible Cu(A) excited states by tuning axial ligand interactions.

  19. [The changes of processes of free radical oxidation of lipids and proteins, antioxidant defence in rats with hypofunction of the thyroid gland in conditions of iodine and copper deficiency].

    Science.gov (United States)

    Voronych-Semchenko, N M; Huranych, T V

    2014-01-01

    Thyroid status, copper balance, correlation of processes of peroxide oxidation of lipids (POL), proteins (POP), antioxidant defence (AOD) were examined in experiments on rats with hypofunction of thyroid gland under iodine monodeficit (HTGI) and combined iodine and copper deficit (HTGI+Cu). It was determined that a combined deficit of microelements is accompanied by a distribution of copper content between different tissues (increase in red blood cell mass and cerebrum, decrease in myocardium), essential changes of indexes of hypotalamo-hypophysis-thyroid axis, oxygen-dependent metabolism, antiradical defense, exacerbating the effects of negative influence of each of them on organism. It was established that HTGI+Cu causes a suppression of oxygen-dependent processes. In thyroid gland, it is shown a decrease of content of dyenic conjugates (DC) by 69,70% , of TBA-reacting products (TBA-RP) by 47,72% in diencephalon, the volume of modified proteins (VMP) - by 37,10-98,98% in the tissues of diencephalons. The results obtained let us to suggest a pivotal role ofmicroelement dysbalance and metabolic mechanisms in pathogenesis of cardiological pathology under thyroid dysfunction. The development of HTGI +Cu exhausts the resources of AOD: decreases the activity of catalase (on 47,05%), superoxide dismutase (on 33,13%), ceruloplasmine (on 33,93%) and saturation of transferrin with iron (on 56,76%) against the background of selective rise in the activity of glu-tationreductase (in 2,8 time) in comparison with the control data. The long-term disturbances ofantyoxidative defence can be the reason of manifestation of oxygendependent processes and the development of pathological changes in separate physiological systems of organism.

  20. THE TRANSATLANTIC BLUE DIPLOMACY

    Directory of Open Access Journals (Sweden)

    Ioana GUTU

    2016-12-01

    Full Text Available The international diplomatic environment has reached to an unprecedented development, involving one of the newly specialized diplomatic types, namely the economic diplomacy. At the core of the fast movements in the diplomatic spheres across the Globe are the international agreements like the Transatlantic Trade and Investment Partnership (TTIP that determined diplomacy to dissolve into new subtypes, evolving from ground to the ocean and implementing new ways of achieving economic and climate sustainability. One of the newly created diplomatic spheres, is the blue ocean diplomacy that acts mainly in accordance with the rules and regulations that are being applied to the transatlantic economy. Even though TTIP encourages the increase of trade flows across the Atlantic, it will also ease the foreign investment procedures that, under the approach of keeping a sustainable environment, will represent one of the most important initiatives in implementing the blue economy concept within the framework of the transatlantic diplomacy.

  1. Faint Blue Galaxies

    CERN Document Server

    Ellis, Richard S

    1997-01-01

    The physical properties of the faint blue galaxy population are reviewed in the context of observational progress made via deep spectroscopic surveys and Hubble Space Telescope imaging of field galaxies at various limits, and theoretical models for the integrated star formation history of the Universe. Notwithstanding uncertainties in the properties of the local population of galaxies, convincing evidence has emerged from several independent studies for a rapid decline in the volume-averaged star formation rate of field galaxies since a redshift z~1. Together with the small angular sizes and modest mean redshift of the faintest detectable sources, these results can be understood in hierarchical models where the bulk of the star formation occurred at redshifts between z~1-2. The physical processes responsible for the subsequent demise of the faint blue galaxy population remains unclear. Considerable progress will be possible when the evolutionary trends can be monitored in the context of independent physical p...

  2. Mitochondrial dysfunction in neurodegenerative diseases associated with copper imbalance.

    Science.gov (United States)

    Rossi, Luisa; Lombardo, Marco F; Ciriolo, Maria R; Rotilio, Giuseppe

    2004-03-01

    Copper is an essential transition metal ion for the function of key metabolic enzymes, but its uncontrolled redox reactivity is source of reactive oxygen species. Therefore a network of transporters strictly controls the trafficking of copper in living systems. Deficit, excess, or aberrant coordination of copper are conditions that may be detrimental, especially for neuronal cells, which are particularly sensitive to oxidative stress. Indeed, the genetic disturbances of copper homeostasis, Menkes' and Wilson's diseases, are associated with neurodegeneration. Furthermore, copper interacts with the proteins that are the hallmarks of neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, prion diseases, and familial amyotrophic lateral sclerosis. In all cases, copper-mediated oxidative stress is linked to mitochondrial dysfunction, which is a common feature of neurodegeneration. In particular we recently demonstrated that in copper deficiency, mitochondrial function is impaired due to decreased activity of cytochrome c oxidase, leading to production of reactive oxygen species, which in turn triggers mitochondria-mediated apoptotic neurodegeneration.

  3. Copper-sulfenate complex from oxidation of a cavity mutant of Pseudomonas aeruginosa azurin

    Energy Technology Data Exchange (ETDEWEB)

    Sieracki, Nathan A.; Tian, Shiliang; Hadt, Ryan G.; Zhang, Jun-Long; Woertink, Julia S.; Nilges, Mark J.; Sun, Furong; Solomon, Edward I.; Lu, Yi [Stanford; (UIUC); (Peking)

    2014-08-25

    Metal–sulfenate centers are known to play important roles in biology and yet only limited examples are known due to their instability and high reactivity. Herein we report a copper–sulfenate complex characterized in a protein environment, formed at the active site of a cavity mutant of an electron transfer protein, type 1 blue copper azurin. Reaction of hydrogen peroxide with Cu(I)–M121G azurin resulted in a species with strong visible absorptions at 350 and 452 nm and a relatively low electron paramagnetic resonance gz value of 2.169 in comparison with other normal type 2 copper centers. The presence of a side-on copper–sulfenate species is supported by resonance Raman spectroscopy, electrospray mass spectrometry using isotopically enriched hydrogen peroxide, and density functional theory calculations correlated to the experimental data. In contrast, the reaction with Cu(II)–M121G or Zn(II)–M121G azurin under the same conditions did not result in Cys oxidation or copper–sulfenate formation. Structural and computational studies strongly suggest that the secondary coordination sphere noncovalent interactions are critical in stabilizing this highly reactive species, which can further react with oxygen to form a sulfinate and then a sulfonate species, as demonstrated by mass spectrometry. Engineering the electron transfer protein azurin into an active copper enzyme that forms a copper–sulfenate center and demonstrating the importance of noncovalent secondary sphere interactions in stabilizing it constitute important contributions toward the understanding of metal–sulfenate species in biological systems.

  4. [Copper IUDs (author's transl)].

    Science.gov (United States)

    Thiery, M

    1983-10-01

    Following initial development of the Grafenberg ring in the 1920's, IUDs fell into disuse until the late 1950s, when plastic devices inserted using new technology began to gain worldwide acceptance. Further research indicated that copper had a significant antifertility effect which increased with increasing surface area, and several copper IUDs were developed and adapted, including the Copper T 200, the Copper T 220C, and the Copper T 380 A, probably the most effective yet. The Gravigard and Multiload are 2 other copper devices developed according to somewhat different principles. Copper devices are widely used not so much because of their great effectiveness as because of their suitability for nulliparous patients and their ease of insertion, which minimizes risk of uterine perforation. Records of 2584 women using Copper IUDs for 7190 women-years and 956 women using devices without copper for 6059 women-years suggest that the copper devices were associated with greater effectiveness and fewer removals for complications. Research suggests that the advantages of copper IUDs become more significant with increased duration of use. Contraindications to copper devices include allergy to copper and hepatolenticular degeneration. No carcinogenic or teratogenic effect of copper devices has been found, but further studies are needed to rule out other undesirable effects. Significant modifications of copper devices in recent years have been developed to increase their effectiveness, prolong their duration of usefulness, facilitate insertion and permit insertion during abortion or delivery. The upper limit of the surface area of copper associated with increased effectiveness appears to be between 200-300 sq mm, and at some point increases in copper exposure may provoke expulsion of the IUD. The duration of fertility inhibition of copper IUDs is usually estimated at 2-3 years, but recent research indicates that it may be 6-8 years, and some devices may retain copper surface

  5. The many "faces" of copper in medicine and treatment.

    Science.gov (United States)

    Hordyjewska, Anna; Popiołek, Łukasz; Kocot, Joanna

    2014-08-01

    Copper (Cu) is an essential microelement found in all living organisms with the unique ability to adopt two different redox states-in the oxidized (Cu(2+)) and reduced (Cu(+)). It is required for survival and serves as an important catalytic cofactor in redox chemistry for proteins that carry out fundamental biological functions, important in growth and development. The deficit of copper can result in impaired energy production, abnormal glucose and cholesterol metabolism, increased oxidative damage, increased tissue iron (Fe) accrual, altered structure and function of circulating blood and immune cells, abnormal neuropeptides synthesis and processing, aberrant cardiac electrophysiology, impaired myocardial contractility, and persistent effects on the neurobehavioral and the immune system. Increased copper level has been found in several disorders like e.g.: Wilson's disease or Menke's disease. New findings with the great potential for impact in medicine include the use of copper-lowering therapy for antiangiogenesis, antifibrotic and anti-inflammatory purposes. The role of copper in formation of amyloid plaques in Alzheimer's disease, and successful treatment of this disorder in rodent model by copper chelating are also of interest. In this work we will try to describe essential aspects of copper in chosen diseases. We will represent the evidence available on adverse effect derived from copper deficiency and copper excess. We will try to review also the copper biomarkers (chosen enzymes) that help reflect the level of copper in the body.

  6. [Phycobiliproteins of blue-green, red and cryptophytic algae].

    Science.gov (United States)

    Stadnichuk, I N; Gusev, M V

    1979-04-01

    The present-day concepts on phycobiliproteins, the protein pigments of blue-green, red and cryptophyte algae are reviewed. The functions, distribution, localization, physico-chemical, spectral and immunochemical properties of phycobiliproteins are described. The properties of the polypeptide protein subunits and the composition and chemical structure of chromophores as well as their binding to the apoprotein molecules are discussed.

  7. Blue ocean leadership.

    Science.gov (United States)

    Kim, W Chan; Mauborgne, Renée

    2014-05-01

    Ten years ago, two INSEAD professors broke ground by introducing "blue ocean strategy," a new model for discovering uncontested markets that are ripe for growth. In this article, they apply their concepts and tools to what is perhaps the greatest challenge of leadership: closing the gulf between the potential and the realized talent and energy of employees. Research indicates that this gulf is vast: According to Gallup, 70% of workers are disengaged from their jobs. If companies could find a way to convert them into engaged employees, the results could be transformative. The trouble is, managers lack a clear understanding of what changes they could make to bring out the best in everyone. Here, Kim and Mauborgne offer a solution to that problem: a systematic approach to uncovering, at each level of the organization, which leadership acts and activities will inspire employees to give their all, and a process for getting managers throughout the company to start doing them. Blue ocean leadership works because the managers' "customers"-that is, the people managers oversee and report to-are involved in identifying what's effective and what isn't. Moreover, the approach doesn't require leaders to alter who they are, just to undertake a different set of tasks. And that kind of change is much easier to implement and track than changes to values and mind-sets.

  8. Transfer of Copper from an Amyloid to a Natural Copper-Carrier Peptide with a Specific Mediating Ligand.

    Science.gov (United States)

    Nguyen, Michel; Bijani, Christian; Martins, Nathalie; Meunier, Bernard; Robert, Anne

    2015-11-16

    The oxidative stress that arises from the catalytic reduction of dioxygen by Cu(II/I)-loaded amyloids is the major pathway for neuron death that occurs in Alzheimer's disease. In this work, we show that bis-8(aminoquinoline) ligands, copper(II) specific chelators, are able to catalytically extract Cu(II) from Cu-Aβ1-16 and then completely release Cu(I) in the presence of glutathione to provide a Cu(I)-glutathione complex, a biological intermediate that is able to deliver copper to apo forms of copper-protein complexes. These data demonstrate that bis-8(aminoquinolines) can perform the transfer of copper ions from the pathological Cu-amyloid complexes to regular copper-protein complexes. These copper-specific ligands assist GSH to recycle Cu(I) in an AD brain and consequently slow down oxidative damage that is due to copper dysregulation in Alzheimer's disease. Under the same conditions, we have shown that the copper complex of PBT2, a mono(8-hydroxyquinoline) previously used as a drug candidate, does not efficiently release copper in the presence of GSH. In addition, we report that GSH itself was unable to fully abstract copper ions from Cu-β-amyloid complexes.

  9. Synthesis and crystal structure of binuclear copper(II) complex bridged by N-(2-hydroxyphenyl)-N'-[3-(diethylamino)propyl]oxamide: in vitro anticancer activity and reactivity toward DNA and protein.

    Science.gov (United States)

    Gao, Yang; Li, Yan-Tuan; Wu, Zhi-Yong; Yan, Cui-Wei

    2013-08-01

    A new oxamido-bridged bicopper(II) complex, [Cu2(pdpox)(bpy)(CH3OH)](ClO4), where H3pdpox and bpy stand for N-(2-hydroxyphenyl)-N'-[3-(diethylamino)propyl]oxamide and 2,2'-bipyridine, respectively, has been synthesized and characterized by elemental analyses, molar conductivity measurements, infrared and electronic spectra studies, and X-ray single crystal diffraction. In the crystal structure, the pdpox(3-) ligand bridges two copper(II) ions as cisoid conformation. The inner copper(II) ion has a {N3O} square-planar coordination geometry, while the exo- one is in a {N2O3} square-pyramidal environment. There are two sets of interpenetrating two-dimensional hydrogen bonding networks parallel to the planes (2 1 0) and (21¯0), respectively, to form a three-dimensional supramolecular structure. The bicopper(II) complex exhibits cytotoxic activity against the SMMC7721 and A549 cell lines. The reactivity toward herring sperm DNA and bovine serum albumin revealed that the bicopper(II) complex can interact with the DNA by intercalation mode, and the complex binds to protein BSA responsible for quenching of tryptophan fluorescence by static quenching mechanism.

  10. A novel Schiff base derived from the gabapentin drug and copper (II) complex: Synthesis, characterization, interaction with DNA/protein and cytotoxic activity.

    Science.gov (United States)

    Shokohi-Pour, Zahra; Chiniforoshan, Hossein; Momtazi-Borojeni, Amir Abbas; Notash, Behrouz

    2016-09-01

    A novel Schiff base [C20H23NO3], has been prepared and characterized using FT-IR, UV-vis, (1)H NMR spectroscopy, elemental analysis and X-ray crystallography. A copper (II) complex [Cu(C20H22NO3)2]·H2O has also been synthesized and characterized. The new ligand and complex thus obtained were investigated by their interaction with calf thymus DNA and BSA using electronic absorption spectroscopy, fluorescence spectroscopy, and thermal denaturation. The intrinsic binding constants Kb of the ligand and Cu (II) complex, with CT-DNA obtained from UV-vis absorption studies were 1.53×10(4)M(-1) and 3.71×10(5)M(-1), respectively. Moreover the addition of the two compounds to CT-DNA (1:2) led to an increase of the melting temperature of DNA up to around 2.61°C for the ligand and 3.99°C for the Cu (II) complex. The ligand and Cu (II) complex bind to CT-DNA via a partial intercalative, as shown by the experimental data. In addition, the albumin interactions of the two compounds were studied by fluorescence quenching spectra, the results indicating that the binding mechanism is a static quenching process. The in vitro cytotoxicity of the two compounds on three different cancer cell lines was evaluated by MTT assay. The results showed that the copper complex exerted enhanced cytotoxicity compared with the Schiff base ligand; thereby, this complex clearly implies a positive synergistic effect. Furthermore, the copper complex showed a high, selective, and dose-dependent cytotoxicity against cancer cell lines.

  11. Postpartum Blues and Postpartum Depression

    Directory of Open Access Journals (Sweden)

    Erdem Ö et al.

    2009-09-01

    Full Text Available Postpartum blues which is seen during the postpartum period is a transient psychological state. Most of the mothers experience maternity blues in postpartum period. It remains usually unrecognized by the others. Some sensitive families can misattribute these feelings as depression. In this article, we tried to review the characteristics of maternity blues and its differences from depression. We defined depression and presented the incidence and diagnostic criteria, of major depression as well as the risk factors and clinic findings of postpartum depression. Thus, especially at primary care we aimed to prevent misdiagnosis of both maternity blues and depression

  12. Protein

    Science.gov (United States)

    ... Food Service Resources Additional Resources About FAQ Contact Protein Protein is found throughout the body—in muscle, ... the heart and respiratory system, and death. All Protein Isn’t Alike Protein is built from building ...

  13. Copper does not alter the intracellular distribution of ATP7B, a copper-transporting ATPase.

    Science.gov (United States)

    Harada, M; Sakisaka, S; Kawaguchi, T; Kimura, R; Taniguchi, E; Koga, H; Hanada, S; Baba, S; Furuta, K; Kumashiro, R; Sugiyama, T; Sata, M

    2000-09-01

    Wilson's disease is a genetic disorder characterized by the accumulation of copper in the body due to a defect of biliary copper excretion. However, the mechanism of biliary copper excretion has not been fully clarified. We examined the effect of copper on the intracellular localization of the Wilson disease gene product (ATP7B) and green fluorescent protein (GFP)-tagged ATP7B in a human hepatoma cell line (Huh7). The intracellular organelles were visualized by fluorescence microscopy. GFP-ATP7B colocalized with late endosome markers, but not with endoplasmic reticulum, Golgi, or lysosome markers in both the steady and copper-loaded states. ATP7B mainly localized at the perinuclear regions in both states. These results suggest that the main localization of ATP7B is in the late endosomes in both the steady and copper-loaded states. ATP7B seems to translocate copper from the cytosol to the late endosomal lumen, thus participating in biliary copper excretion via lysosomes.

  14. 铜及铜合金着色%Coloring of copper and copper alloys

    Institute of Scientific and Technical Information of China (English)

    程沪生

    2011-01-01

    简述了铜及铜合金着色的原理.总结了铜及铜合金着黑色、褐色、绿色、蓝色的工艺配方及操作条件,介绍了手工点涂铜绿(铜锈)、双色点蚀(先着黑色再点蚀铜绿)、套色、着土黄铜绿色等多种特殊的着色工艺.%The principle of coloring of copper and copper alloys was described. The process formulations and operation conditions for obtaining black, brown, green, and blue colors on copper and copper alloys were summarized. Some special coloring processes were introduced, such as spot coating to form patina (green corrosion products of copper), black coloring followed by spot corrosion to form two tones, covering with another color on a previously colored workpiece, and successive coloring with khaki and green.

  15. Instant BlueStacks

    CERN Document Server

    Judge, Gary

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A fast-paced, example-based approach guide for learning BlueStacks.This book is for anyone with a Mac or PC who wants to run Android apps on their computer. Whether you want to play games that are freely available for Android but not your computer, or you want to try apps before you install them on a physical device or use it as a development tool, this book will show you how. No previous experience is needed as this is written in plain English

  16. Methylene Blue Inhibits Caspases by Oxidation of the Catalytic Cysteine.

    Science.gov (United States)

    Pakavathkumar, Prateep; Sharma, Gyanesh; Kaushal, Vikas; Foveau, Bénédicte; LeBlanc, Andrea C

    2015-09-24

    Methylene blue, currently in phase 3 clinical trials against Alzheimer Disease, disaggregates the Tau protein of neurofibrillary tangles by oxidizing specific cysteine residues. Here, we investigated if methylene blue can inhibit caspases via the oxidation of their active site cysteine. Methylene blue, and derivatives, azure A and azure B competitively inhibited recombinant Caspase-6 (Casp6), and inhibited Casp6 activity in transfected human colon carcinoma cells and in serum-deprived primary human neuron cultures. Methylene blue also inhibited recombinant Casp1 and Casp3. Furthermore, methylene blue inhibited Casp3 activity in an acute mouse model of liver toxicity. Mass spectrometry confirmed methylene blue and azure B oxidation of the catalytic Cys163 cysteine of Casp6. Together, these results show a novel inhibitory mechanism of caspases via sulfenation of the active site cysteine. These results indicate that methylene blue or its derivatives could (1) have an additional effect against Alzheimer Disease by inhibiting brain caspase activity, (2) be used as a drug to prevent caspase activation in other conditions, and (3) predispose chronically treated individuals to cancer via the inhibition of caspases.

  17. A study of the effects of phosphates on copper corrosion in drinking water: Copper release, electrochemical, and surface analysis approach

    Science.gov (United States)

    Kang, Young C.

    by ToF-SIMS. Dynamic SIMS provided shallow depth profile of corroded copper sample. The third set of the experiments was related to electrochemical noise (EN) measurement through copper coupons to pipes. Calculating corrosion rate of a metal and predicting exactly how long it lasts are problematic since the metal corrosion may be caused by combined corrosion types. Many other metals undergo not only uniform corrosion, but localized corrosion. Uniform corrosion may be conducive for copper pipe to prevent it from further severe corrosion and form passivated film, but localized corrosion causes pinhole leaks and limits the copper pipe applications. The objective of this set of experiment is to discuss the application of electrochemical noise approaches to drinking water copper corrosion problems. Specially, a fundamental description of EN is presented including a discussion of how to interpret the results and technique limitations. Although it was indicated with electrochemical analysis that the corrosion activity was affected by orthophosphate addition in the short-term test, no copper-phosphate complex or compound was found by copper surface characterization. Apparently, orthophosphate can inhibit corrosion by adsorption on the copper surface, but cannot form solid complexes with copper in such a short time, 2 days. When polyphosphate was added into recirculating copper pipe system, copper level increased and polarization resistance decreased. Greenish blue residue on the copper pipe was suspected as copper phosphate complex and corrosion inhibition mechanism was proposed.

  18. Effects of methionine chelate- or yeast proteinate-based supplement of copper, iron, manganese and zinc on broiler growth performance, their distribution in the tibia and excretion into the environment.

    Science.gov (United States)

    Singh, Abhay Kumar; Ghosh, Tapan Kumar; Haldar, Sudipto

    2015-04-01

    A straight-run flock of 1-day-old Cobb 400 chicks (n = 432) was distributed into four treatment groups (9 replicate pens in each group, 12 birds in a pen) for a 38-day feeding trial evaluating the effects of a methionine chelate (Met-TM)- or a yeast proteinate (Yeast-TM)-based supplement of copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) on growth performance, bone criteria and some metabolic indices in commercial broiler chickens. The diets were either not supplemented with any trace elements at all (negative control, NC) or supplemented with an inorganic (sulphate) trace element premix (inorganic TM (ITM), 1 g/kg feed), the Met-TM (1 g/kg feed) and the Yeast-TM (0.5 g/kg feed). Body weight, feed conversion ratio and dressed meat yield at 38 days were better in the Yeast-TM-supplemented group as compared with the NC, ITM and Met-TM groups (p chelates or yeast proteinate forms of Cu, Fe, Mn and Zn improved body weight and feed conversion ratio (FCR) and markedly reduced excretion of the said trace elements. The study revealed that it may be possible to improve broiler performance and reduce excretion of critical trace elements into the environment by complete replacement of inorganic trace minerals from their dietary regime and replacing the same with methionine chelate or yeast proteinate forms.

  19. Handling of Copper and Copper Oxide Nanoparticles by Astrocytes.

    Science.gov (United States)

    Bulcke, Felix; Dringen, Ralf

    2016-02-01

    Copper is an essential trace element for many important cellular functions. However, excess of copper can impair cellular functions by copper-induced oxidative stress. In brain, astrocytes are considered to play a prominent role in the copper homeostasis. In this short review we summarise the current knowledge on the molecular mechanisms which are involved in the handling of copper by astrocytes. Cultured astrocytes efficiently take up copper ions predominantly by the copper transporter Ctr1 and the divalent metal transporter DMT1. In addition, copper oxide nanoparticles are rapidly accumulated by astrocytes via endocytosis. Cultured astrocytes tolerate moderate increases in intracellular copper contents very well. However, if a given threshold of cellular copper content is exceeded after exposure to copper, accelerated production of reactive oxygen species and compromised cell viability are observed. Upon exposure to sub-toxic concentrations of copper ions or copper oxide nanoparticles, astrocytes increase their copper storage capacity by upregulating the cellular contents of glutathione and metallothioneins. In addition, cultured astrocytes have the capacity to export copper ions which is likely to involve the copper ATPase 7A. The ability of astrocytes to efficiently accumulate, store and export copper ions suggests that astrocytes have a key role in the distribution of copper in brain. Impairment of this astrocytic function may be involved in diseases which are connected with disturbances in brain copper metabolism.

  20. Copper as a key regulator of cell signalling pathways.

    Science.gov (United States)

    Grubman, Alexandra; White, Anthony R

    2014-05-22

    Copper is an essential element in many biological processes. The critical functions associated with copper have resulted from evolutionary harnessing of its potent redox activity. This same property also places copper in a unique role as a key modulator of cell signal transduction pathways. These pathways are the complex sequence of molecular interactions that drive all cellular mechanisms and are often associated with the interplay of key enzymes including kinases and phosphatases but also including intracellular changes in pools of smaller molecules. A growing body of evidence is beginning to delineate the how, when and where of copper-mediated control over cell signal transduction. This has been driven by research demonstrating critical changes to copper homeostasis in many disorders including cancer and neurodegeneration and therapeutic potential through control of disease-associated cell signalling changes by modulation of copper-protein interactions. This timely review brings together for the first time the diverse actions of copper as a key regulator of cell signalling pathways and discusses the potential strategies for controlling disease-associated signalling processes using copper modulators. It is hoped that this review will provide a valuable insight into copper as a key signal regulator and stimulate further research to promote our understanding of copper in disease and therapy.

  1. Proteomic analysis of the copper resistance of Streptococcus pneumoniae.

    Science.gov (United States)

    Guo, Zhong; Han, Junlong; Yang, Xiao-Yan; Cao, Kun; He, Ke; Du, Gaofei; Zeng, Guandi; Zhang, Liang; Yu, Guangchuang; Sun, Zhenghua; He, Qing-Yu; Sun, Xuesong

    2015-03-01

    Streptococcus pneumoniae is a Gram-positive bacterial pathogen causing a variety of diseases, including otitis media, bacteraemia and meningitis. Although copper is an essential trace metal for bacterial growth, high intracellular levels of free-copper are toxic. Copper resistance has emerged as an important virulence determinant of microbial pathogens. In this study, we determined the minimum inhibition concentration of copper for the growth inhibition of S. pneumoniae. Two-dimensional-electrophoresis coupled with mass spectrometry was applied to identify proteins involved in copper resistance of S. pneumoniae. In total, forty-four proteins with more than 1.5-fold alteration in expression (p < 0.05) were identified. Quantitative reverse transcription PCR was used to confirm the proteomic results. Bioinformatics analysis showed that the differentially expressed proteins were mainly involved in the cell wall biosynthesis, protein biosynthesis, purine biosynthesis, pyrimidine biosynthesis, primary metabolic process, and the nitrogen compound metabolic process. Many up-regulated proteins in response to the copper treatment directly or indirectly participated in the cell wall biosynthesis, indicating that the cell wall is a critical determinant in copper resistance of S. pneumoniae.

  2. Canine models of copper toxicosis for understanding mammalian copper metabolism

    OpenAIRE

    Fieten, Hille; Leegwater, Peter A. J.; Watson, Adrian L.; Rothuizen, Jan

    2011-01-01

    Hereditary forms of copper toxicosis exist in man and dogs. In man, Wilson’s disease is the best studied disorder of copper overload, resulting from mutations in the gene coding for the copper transporter ATP7B. Forms of copper toxicosis for which no causal gene is known yet are recognized as well, often in young children. Although advances have been made in unraveling the genetic background of disorders of copper metabolism in man, many questions regarding disease mechanisms and copper homeo...

  3. Surface plasmon effect in nanocrystalline copper/DLC composite films by electrodeposition technique

    Indian Academy of Sciences (India)

    S Hussain; A K Pal

    2006-11-01

    Composite films of nanocrystalline copper embedded in DLC matrix prepared by electrodeposition technique were studied for their optical properties. Particle size and metal volume fractions were tailored by varying the amount of copper containing salt in the electrolyte. Blue-shift of the surface plasmon resonance peak in the absorbance spectra of the films was observed with the reduction in size and volume fraction of metal particles. Mie theory was found to describe the experimental spectra quite well.

  4. Role of the P-Type ATPases, ATP7A and ATP7B in brain copper homeostasis.

    Science.gov (United States)

    Telianidis, Jonathon; Hung, Ya Hui; Materia, Stephanie; Fontaine, Sharon La

    2013-01-01

    Over the past two decades there have been significant advances in our understanding of copper homeostasis and the pathological consequences of copper dysregulation. Cumulative evidence is revealing a complex regulatory network of proteins and pathways that maintain copper homeostasis. The recognition of copper dysregulation as a key pathological feature in prominent neurodegenerative disorders such as Alzheimer's, Parkinson's, and prion diseases has led to increased research focus on the mechanisms controlling copper homeostasis in the brain. The copper-transporting P-type ATPases (copper-ATPases), ATP7A and ATP7B, are critical components of the copper regulatory network. Our understanding of the biochemistry and cell biology of these complex proteins has grown significantly since their discovery in 1993. They are large polytopic transmembrane proteins with six copper-binding motifs within the cytoplasmic N-terminal domain, eight transmembrane domains, and highly conserved catalytic domains. These proteins catalyze ATP-dependent copper transport across cell membranes for the metallation of many essential cuproenzymes, as well as for the removal of excess cellular copper to prevent copper toxicity. A key functional aspect of these copper transporters is their copper-responsive trafficking between the trans-Golgi network and the cell periphery. ATP7A- and ATP7B-deficiency, due to genetic mutation, underlie the inherited copper transport disorders, Menkes and Wilson diseases, respectively. Their importance in maintaining brain copper homeostasis is underscored by the severe neuropathological deficits in these disorders. Herein we will review and update our current knowledge of these copper transporters in the brain and the central nervous system, their distribution and regulation, their role in normal brain copper homeostasis, and how their absence or dysfunction contributes to disturbances in copper homeostasis and neurodegeneration.

  5. Role of the P-Type ATPases, ATP7A and ATP7B in brain copper homeostasis

    Directory of Open Access Journals (Sweden)

    Jonathon eTelianidis

    2013-08-01

    Full Text Available Over the past two decades there have been significant advances in our understanding of copper homeostasis and the pathological consequences of copper dysregulation. Cumulative evidence is revealing a complex regulatory network of proteins and pathways that maintain copper homeostasis. The recognition of copper dysregulation as a key pathological feature in prominent neurodegenerative disorders such as Alzheimer’s, Parkinson’s and prion diseases has led to increased research focus on the mechanisms controlling copper homeostasis in the brain. The copper-transporting P-Type ATPases (copper-ATPases, ATP7A and ATP7B, are critical components of the copper regulatory network. Our understanding of the biochemistry and cell biology of these complex proteins has grown significantly since their discovery in 1993. They are large polytopic transmembrane proteins with six copper-binding motifs within the cytoplasmic N-terminal domain, eight transmembrane domains and highly conserved catalytic domains. These proteins catalyze ATP-dependent copper transport across cell membranes for the metallation of many essential cuproenzymes, as well as for the removal of excess cellular copper to prevent copper toxicity. A key functional aspect of these copper transporters is their copper-responsive trafficking between the trans-Golgi network and the cell periphery. ATP7A- and ATP7B-deficiency, due to genetic mutation, underlie the inherited copper transport disorders, Menkes and Wilson diseases, respectively. Their importance in maintaining brain copper homeostasis is underscored by the severe neuropathological deficits in these disorders. Herein we will review and update our current knowledge of these copper transporters in the brain and the central nervous system, their distribution and regulation, their role in normal brain copper homeostasis and how their absence or dysfunction contributes to disturbances in copper homeostasis and neurodegeneration.

  6. Hair copper in intrauterine copper device users.

    Science.gov (United States)

    Thiery, M; Heyndrickx, A; Uyttersprot, C

    1984-03-01

    The antifertility effect of copper-bearing IUDs is based on continuous release of copper, which is a result of the reaction between the metal and the uterine secretions. Released cupric ions collect in the endometrium and in the uterine fluid but significant accumulation has not been found in the bloodstream or elsewhere. Following Laker's suggestion that hair be used for monitoring essential trace elements, e.g., copper, we checked the copper content of the hair of women wearing copper-bearing IUDs. Samples of untreated pubic hair removed by clipping before diagnostic curettage were obtained from 10 young (24-34 years old), white caucasian females who until then had been wearing an MLCu250 IUD for more than 1 year. Pubes from 10 comparable (sex, age, race) subjects who had never used a Cu-containing device served as controls. The unwashed material was submitted to the toxicology laboratory, where the copper content was assessed by flameless atomic absorption, a technique whose lower limit of measurement lies at a concentration of 0.05 mcg Cu/ml fluid (50 ppb). Hair samples were washed to remove extraneous traces of metal according to the prescriptions of the International Atomic Energy Agency, weighed, and mineralized, after which a small volume (10 mcl) of the diluted fluid was fed into the graphite furnace. Each sample (75-150 mg) was analyzed 4 times, both before and after washing. Since the cleaning procedure reduces the weight of the sample (mainly by the removal of fat, dust, etc.) this explains why the percentage copper content of washed hair is higher than that of unwashed hair belonging to the same subject. The results indicate that there was no significant difference (Mann-Whitney U test) between the mean copper levels of both unwashed and washed pubes from women who were using or had never used an MLCu250 IUD. We therefore conclude that the use of this copper-containing device is not associated with significant accumulation of copper in (pubic) hair.

  7. Biogenic nanoparticles: copper, copper oxides, copper sulphides, complex copper nanostructures and their applications.

    Science.gov (United States)

    Rubilar, Olga; Rai, Mahendra; Tortella, Gonzalo; Diez, Maria Cristina; Seabra, Amedea B; Durán, Nelson

    2013-09-01

    Copper nanoparticles have been the focus of intensive study due to their potential applications in diverse fields including biomedicine, electronics, and optics. Copper-based nanostructured materials have been used in conductive films, lubrification, nanofluids, catalysis, and also as potent antimicrobial agent. The biogenic synthesis of metallic nanostructured nanoparticles is considered to be a green and eco-friendly technology since neither harmful chemicals nor high temperatures are involved in the process. The present review discusses the synthesis of copper nanostructured nanoparticles by bacteria, fungi, and plant extracts, showing that biogenic synthesis is an economically feasible, simple and non-polluting process. Applications for biogenic copper nanoparticles are also discussed.

  8. Blue moons and Martian sunsets.

    Science.gov (United States)

    Ehlers, Kurt; Chakrabarty, Rajan; Moosmüller, Hans

    2014-03-20

    The familiar yellow or orange disks of the moon and sun, especially when they are low in the sky, and brilliant red sunsets are a result of the selective extinction (scattering plus absorption) of blue light by atmospheric gas molecules and small aerosols, a phenomenon explainable using the Rayleigh scattering approximation. On rare occasions, dust or smoke aerosols can cause the extinction of red light to exceed that for blue, resulting in the disks of the sun and moon to appear as blue. Unlike Earth, the atmosphere of Mars is dominated by micron-size dust aerosols, and the sky during sunset takes on a bluish glow. Here we investigate the role of dust aerosols in the blue Martian sunsets and the occasional blue moons and suns on Earth. We use the Mie theory and the Debye series to calculate the wavelength-dependent optical properties of dust aerosols most commonly found on Mars. Our findings show that while wavelength selective extinction can cause the sun's disk to appear blue, the color of the glow surrounding the sun as observed from Mars is due to the dominance of near-forward scattering of blue light by dust particles and cannot be explained by a simple, Rayleigh-like selective extinction explanation.

  9. China Copper Processing Industry Focus

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>1. Market Consumption The ’China Factor’ and Copper Price Fluctuation We all know China is an enormous consumer of copper,but the exact levels of consumption and where the copper has gone remains a mystery.

  10. Mono-nuclear copper complexes mimicking the intermediates for the binuclear copper center of the subunit II of cytochrome oxidase: a peptide based approach.

    Science.gov (United States)

    Dutta Gupta, Dwaipayan; Usharani, Dandamudi; Mazumdar, Shyamalava

    2016-11-28

    Three stable copper complexes of peptides derived from the copper ion binding loop of the subunit II of cytochrome c oxidase have been prepared and characterized by various spectroscopic techniques. These stable copper complexes of peptides were found to exhibit cysteine, histidine and/or methionine ligation, which has predominant σ-contribution in the Cys-Cu charge transfer. The copper(ii) peptide complexes showed type-2 EPR spectra, which is uncommon in copper-cysteinate complexes. UV-visible spectra, Raman and EPR results support a tetragonal structure of the coordination geometry around the copper ion. The copper complex of the 9-amino acid peptide suggested the formation of a 'red' copper center while the copper complexes of the 12- and 11-amino acid peptides showed the formation of a 'green' copper center. The results provide insights on the first stable models of the copper complexes formed in the peptide scaffold that mimic the mono-nuclear copper bound protein intermediates proposed during the formation of the binuclear Cu2S2 core of the enzyme. These three copper complexes of peptides derived from the metal ion binding loop of the CuA center of the subunit II of cytochrome c oxidase showed novel spectroscopic properties which have not so far been reported in any stable small complex.

  11. Carbonic Anhydrase II: A Model System for Artificial Copper Center Design, Protein-guided Cycloadditions, Tethering Screenings and Fragment-based Lead Discovery

    OpenAIRE

    Schulze Wischeler, Johannes

    2010-01-01

    In this thesis a variety of quite different fragment-based lead discovery approaches have been applied to the target protein carbonic anhydrase II. The different projects were strongly supported and methodologically tailored towards protein crystallography; a method which is currently emerging as a routine analytical tool. This maturation mainly results from improved radiation sources and enhanced computing power. About 200-250 da...

  12. Blue Man袭东京

    Institute of Scientific and Technical Information of China (English)

    Naomi Saeki; 李宝怡

    2008-01-01

    <正>20年前在美国曼克顿风靡一时的Blue Man Group,最近在东京出现,马上成为城中话题。在东京,每年有不少舞台剧演出,但是像Blue Man Group这样备受注目的,近年罕见。Blue Man Group in Tokyo于上年12月开始公演·1个月的门票早在9月中旬

  13. Retention behaviour of proteins on poly(vinylimidazole)-copper(II) complexes supported on silica: application to the fractionation of desialylated human alpha 1-acid glycoprotein variants.

    Science.gov (United States)

    Millot, M C; Hervé, F; Sébille, B

    1995-02-03

    The retention behaviour of various amino acids, peptides and proteins on poly(vinylimidazole)-Cu(II) complexes supported on silica was investigated. Free amino acids and peptides containing one histidine and in some instances one additional tryptophan residue in their primary structure were found to elute from the supports only after addition of a competing complexing agent to the mobile phase. However, the results obtained the proteins containing metal binding groups suggested that, in addition to the presence of donor-acceptor interactions between the macromolecules and the immobilized metal, other additional (essentially ionic and/or hydrophobic) interactions took place between the proteins and the surrounding of the metal. When donor-acceptor interactions were predominant, proteins were strongly adsorbed on the stationary phase and their elution required the addition of a competing complexing agent in the mobile phase. However, when the binding between the proteins and the supports via donor-acceptor interactions was less favourable, proteins were eluted from the columns without the addition of a competing agent in the mobile phase. With respect to the binding of these proteins, ionic and/or hydrophobic interactions were no longer negligible during the chromatographic process and the retention of the macromolecules by the stationary phase depended on the elution conditions (ionic strength, pH, etc.). These supports were used in the fractionation of the three main genetic variants of desialylated alpha 1-acid glycoprotein.

  14. Spectroscopic and DFT studies of second-sphere variants of the type 1 copper site in azurin: covalent and nonlocal electrostatic contributions to reduction potentials.

    Science.gov (United States)

    Hadt, Ryan G; Sun, Ning; Marshall, Nicholas M; Hodgson, Keith O; Hedman, Britt; Lu, Yi; Solomon, Edward I

    2012-10-10

    The reduction potentials (E(0)) of type 1 (T1) or blue copper (BC) sites in proteins and enzymes with identical first coordination spheres around the redox active copper ion can vary by ~400 mV. Here, we use a combination of low-temperature electronic absorption and magnetic circular dichroism, electron paramagnetic resonance, resonance Raman, and S K-edge X-ray absorption spectroscopies to investigate a series of second-sphere variants--F114P, N47S, and F114N in Pseudomonas aeruginosa azurin--which modulate hydrogen bonding to and protein-derived dipoles nearby the Cu-S(Cys) bond. Density functional theory calculations correlated to the experimental data allow for the fractionation of the contributions to tuning E(0) into covalent and nonlocal electrostatic components. These are found to be significant, comparable in magnitude, and additive for active H-bonds, while passive H-bonds are mostly nonlocal electrostatic in nature. For dipoles, these terms can be additive to or oppose one another. This study provides a methodology for uncoupling covalency from nonlocal electrostatics, which, when coupled to X-ray crystallographic data, distinguishes specific local interactions from more long-range protein/active interactions, while affording further insight into the second-sphere mechanisms available to the protein to tune the E(0) of electron-transfer sites in biology.

  15. China Mobile: Expanding "Blue Ocean"

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Driving force is crucial for realizing high-speed growth. The strong driving force from "Blue Ocean Strategy" is an important advantage for China Mobile to realize harmonious and leap-forward development.

  16. Karner Blue Butterfly Recovery Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This recovery plan has been prepared by the Karner Blue Butterfly Recovery Team under the leadership of Dr. David Andow, University of Minnesota-St. Paul. Dr. John...

  17. Ecology of blue straggler stars

    CERN Document Server

    Carraro, Giovanni; Beccari, Giacomo

    2015-01-01

    The existence of blue straggler stars, which appear younger, hotter, and more massive than their siblings, is at odds with a simple picture of stellar evolution. Such stars should have exhausted their nuclear fuel and evolved long ago to become cooling white dwarfs. They are found to exist in globular clusters, open clusters, dwarf spheroidal galaxies of the Local Group, OB associations and as field stars. This book summarises the many advances in observational and theoretical work dedicated to blue straggler stars. Carefully edited extended contributions by well-known experts in the field cover all the relevant aspects of blue straggler stars research: Observations of blue straggler stars in their various environments; Binary stars and formation channels; Dynamics of globular clusters; Interpretation of observational data and comparison with models. The book also offers an introductory chapter on stellar evolution written by the editors of the book.

  18. Copper and silver halates

    CERN Document Server

    Woolley, EM; Salomon, M

    2013-01-01

    Copper and Silver Halates is the third in a series of four volumes on inorganic metal halates. This volume presents critical evaluations and compilations for halate solubilities of the Group II metals. The solubility data included in this volume are those for the five compounds, copper chlorate and iodate, and silver chlorate, bromate and iodate.

  19. Coping with copper

    DEFF Research Database (Denmark)

    Nunes, Ines; Jacquiod, Samuel; Brejnrod, Asker

    2016-01-01

    Copper has been intensively used in industry and agriculture since mid-18(th) century and is currently accumulating in soils. We investigated the diversity of potential active bacteria by 16S rRNA gene transcript amplicon sequencing in a temperate grassland soil subjected to century-long exposure......, suggesting a potential promising role as bioindicators of copper contamination in soils....

  20. Expression Analysis of Copper Transporter-related Protein of Cancer in 75 Cases of Colon Cancer Patients%75例结肠癌患者癌组织铜转运相关蛋白表达分析

    Institute of Scientific and Technical Information of China (English)

    张晓晓; 许建华; 张勇; 孙珏; 陆文秀

    2013-01-01

    Objective To investigate the relationship in the expression of copper transporter-related pro-tein such as ATP7A,ATP7B and CTR1, clinicopathological features and prognosis. Methods Expres-sion area ratio of CTR1, ATP7B and ATP7A of tissue microarray, from 75 cancerous tissues specimens which had not been treated, provided by Shanghai Outdo Biotech Co.,Ltd., were analyzed. The relation-ship of copper transporter-related protein and clinicopathological features, 26 cases of the relationship with the patient survival were also analyzed. Results There was no correlation between expression lev-els of ATP7A, ATP7B, CTR1 and sex and tumor stage(P>0.05),while age-related(P0.05). Conclusion In colon cancer,there were no relation in copper transporter-related protein expression levels, gender and tumor stage. But it was related to age. ATP7A,ATP7B was expressed in the cytoplasm of the nu-cleus,and no expression in the cell membrane;The ATP7A nucleus expression is higher than the cyto-plasm. ATP7B evenly was distributed in the cytoplasm and nucleus; CTR1 was expressed mainly in the cytoplasm,nucleus and cell membrane were almost no expression; The subcellular localization and ex-pression rate of CTR1,ATP7A and ATP7B are irrelevant with the survival time.%目的探讨结肠癌组织中铜转运相关蛋白ATP7A、ATP7B和CTR1的表达与患者临床病理特征及预后的关系。方法对上海芯超生物科技有限公司提供的75例未进行任何治疗的癌组织标本组织芯片的 CTR1、ATP7B 和ATP7A表达面积比率进行统计分析。分析铜转运相关蛋白表达与患者临床病理特征的关系,并分析其中26例与患者生存期的关系。结果 ATP7A、ATP7B和CTR1表达水平与性别及肿瘤分期均无相关性(P>0.05),与年龄有关(P0.05)。结论在结肠癌中铜转运相关蛋白表达水平与性别及肿瘤分期均无关,与年龄大小有关;ATP7A、ATP7B在胞浆、胞核中均有表达,在

  1. Kunpeng Copper:The largest Copper Smelting Company of Sichuan

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>On September 9,Liangshan Mining Company’s 100,000 tons/year cathode copper project kicked off.It is another key project of the company following the successful launch of the 100,000 tons/year anode copper project.Based on ISA copper smelting technology of the largest open-cast copper mine in southwest China,

  2. Copper signaling axis as a target for prostate cancer therapeutics.

    Science.gov (United States)

    Safi, Rachid; Nelson, Erik R; Chitneni, Satish K; Franz, Katherine J; George, Daniel J; Zalutsky, Michael R; McDonnell, Donald P

    2014-10-15

    Previously published reports indicate that serum copper levels are elevated in patients with prostate cancer and that increased copper uptake can be used as a means to image prostate tumors. It is unclear, however, to what extent copper is required for prostate cancer cell function as we observed only modest effects of chelation strategies on the growth of these cells in vitro. With the goal of exploiting prostate cancer cell proclivity for copper uptake, we developed a "conditional lethal" screen to identify compounds whose cytotoxic actions were manifested in a copper-dependent manner. Emerging from this screen was a series of dithiocarbamates, which, when complexed with copper, induced reactive oxygen species-dependent apoptosis of malignant, but not normal, prostate cells. One of the dithiocarbamates identified, disulfiram (DSF), is an FDA-approved drug that has previously yielded disappointing results in clinical trials in patients with recurrent prostate cancer. Similarly, in our studies, DSF alone had a minimal effect on the growth of prostate cancer tumors when propagated as xenografts. However, when DSF was coadministered with copper, a very dramatic inhibition of tumor growth in models of hormone-sensitive and of castrate-resistant disease was observed. Furthermore, we determined that prostate cancer cells express high levels of CTR1, the primary copper transporter, and additional chaperones that are required to maintain intracellular copper homeostasis. The expression levels of most of these proteins are increased further upon treatment of androgen receptor (AR)-positive prostate cancer cell lines with androgens. Not surprisingly, robust CTR1-dependent uptake of copper into prostate cancer cells was observed, an activity that was accentuated by activation of AR. Given these data linking AR to intracellular copper uptake, we believe that dithiocarbamate/copper complexes are likely to be effective for the treatment of patients with prostate cancer whose

  3. Effect of excess iron and copper on physiology of aquatic plant Spirodela polyrrhiza (L.) Schleid.

    Science.gov (United States)

    Xing, Wei; Huang, Wenmin; Liu, Guihua

    2010-04-01

    To elucidate effect of chemical reagents addition on growth of aquatic plants in restoration of aquatic ecosystem, Spirodela polyrrhiza (L.) Schleid was used to evaluate its physiological responses to excess iron (Fe(3+)) and copper (Cu(2+)) in the study. Results showed that accumulation of iron and copper both reached maximum at 100 mg L(-1) iron or copper after 24 h short-term stress, but excess iron and copper caused plants necrosis or death and colonies disintegration as well as roots abscission at excess metal concentrations except for 1 mg L(-1) iron. Significant differences in chlorophyll fluorescence (Fv/Fm) were observed at 1-100 mg L(-1) iron or copper. The synthesis of chlorophyll and protein as well as carbohydrate and the uptake of phosphate and nitrogen were inhibited seriously by excess iron and copper. Proline content decreased with increasing iron or copper concentration, however, MDA content increased with increasing iron or copper concentration.

  4. Gene expression profiling and phenotype analyses of S. cerevisiae in response to changing copper reveals six genes with new roles in copper and iron metabolism.

    Science.gov (United States)

    van Bakel, Harm; Strengman, Eric; Wijmenga, Cisca; Holstege, Frank C P

    2005-08-11

    Exhaustive microarray time course analyses of Saccharomyces cerevisiae during copper starvation and copper excess reveal new aspects of metal-induced gene regulation. Aside from identifying targets of established copper- and iron-responsive transcription factors, we find that genes encoding mitochondrial proteins are downregulated and that copper-independent iron transport genes are preferentially upregulated, both during prolonged copper deprivation. The experiments also suggest the presence of a small regulatory iron pool that links copper and iron responses. One hundred twenty-eight genes with putative roles in metal metabolism were further investigated by several systematic phenotype screens. Of the novel phenotypes uncovered, hsp12-Delta and arn1-Delta display increased sensitivity to copper, cyc1-Delta and crr1-Delta show resistance to high copper, vma13-Delta exhibits increased sensitivity to iron deprivation, and pep12-Delta results in reduced growth in high copper and low iron. Besides revealing new components of eukaryotic metal trafficking pathways, the results underscore the previously determined intimate links between iron and copper metabolism and mitochondrial and vacuolar function in metal trafficking. The analyses further suggest that copper starvation can specifically lead to downregulation of respiratory function to preserve iron and copper for other cellular processes.

  5. Altered microglial copper homeostasis in a mouse model of Alzheimer's disease.

    Science.gov (United States)

    Zheng, Zhiqiang; White, Carine; Lee, Jaekwon; Peterson, Troy S; Bush, Ashley I; Sun, Grace Y; Weisman, Gary A; Petris, Michael J

    2010-09-01

    Alzheimer's disease (AD) is characterized by progressive neurodegeneration associated with the aggregation and deposition of β-amyloid (Aβ(40) and Aβ(42) ) peptide in senile plaques. Recent studies suggest that copper may play an important role in AD pathology. Copper concentrations are elevated in amyloid plaques and copper binds with high affinity to the Aβ peptide and promotes Aβ oligomerization and neurotoxicity. Despite this connection between copper and AD, it is unknown whether the expression of proteins involved in regulating copper homeostasis is altered in this disorder. In this study, we demonstrate that the copper transporting P-type ATPase, ATP7A, is highly expressed in activated microglial cells that are specifically clustered around amyloid plaques in the TgCRND8 mouse model of AD. Using a cultured microglial cell line, ATP7A expression was found to be increased by the pro-inflammatory cytokine interferon-gamma, but not by TNF-α or IL-1β. Interferon-gamma also elicited marked changes in copper homeostasis, including copper-dependent trafficking of ATP7A from the Golgi to cytoplasmic vesicles, increased copper uptake and elevated expression of the CTR1 copper importer. These findings suggest that pro-inflammatory conditions associated with AD cause marked changes in microglial copper trafficking, which may underlie the changes in copper homeostasis in AD. It is concluded that copper sequestration by microglia may provide a neuroprotective mechanism in AD.

  6. "Clothed in triple blues": sorting out the Italian blues.

    Science.gov (United States)

    Bimler, David; Uusküla, Mari

    2014-04-01

    Cross-cultural comparisons of color perception and cognition often feature versions of the "similarity sorting" procedure. By interpreting the assignment of two color samples to different groups as an indication that the dissimilarity between them exceeds some threshold, sorting data can be regarded as low-resolution similarity judgments. Here we analyze sorting data from speakers of Italian, Russian, and English, applying multidimensional scaling to delineate the boundaries between perceptual categories while highlighting differences between the three populations. Stimuli were 55 color swatches, predominantly from the blue region. Results suggest that at least two Italian words for "blue" are basic, a similar situation to Russian, in contrast to English where a single "blue" term is basic.

  7. Fabricating Copper Nanotubes by Electrodeposition

    Science.gov (United States)

    Yang, E. H.; Ramsey, Christopher; Bae, Youngsam; Choi, Daniel

    2009-01-01

    Copper tubes having diameters between about 100 and about 200 nm have been fabricated by electrodeposition of copper into the pores of alumina nanopore membranes. Copper nanotubes are under consideration as alternatives to copper nanorods and nanowires for applications involving thermal and/or electrical contacts, wherein the greater specific areas of nanotubes could afford lower effective thermal and/or electrical resistivities. Heretofore, copper nanorods and nanowires have been fabricated by a combination of electrodeposition and a conventional expensive lithographic process. The present electrodeposition-based process for fabricating copper nanotubes costs less and enables production of copper nanotubes at greater rate.

  8. Molybdate Reduction to Molybdenum Blue by an Antarctic Bacterium

    Directory of Open Access Journals (Sweden)

    S. A. Ahmad

    2013-01-01

    Full Text Available A molybdenum-reducing bacterium from Antarctica has been isolated. The bacterium converts sodium molybdate or Mo6+ to molybdenum blue (Mo-blue. Electron donors such as glucose, sucrose, fructose, and lactose supported molybdate reduction. Ammonium sulphate was the best nitrogen source for molybdate reduction. Optimal conditions for molybdate reduction were between 30 and 50 mM molybdate, between 15 and 20°C, and initial pH between 6.5 and 7.5. The Mo-blue produced had a unique absorption spectrum with a peak maximum at 865 nm and a shoulder at 710 nm. Respiratory inhibitors such as antimycin A, sodium azide, potassium cyanide, and rotenone failed to inhibit the reducing activity. The Mo-reducing enzyme was partially purified using ion exchange and gel filtration chromatography. The partially purified enzyme showed optimal pH and temperature for activity at 6.0 and 20°C, respectively. Metal ions such as cadmium, chromium, copper, silver, lead, and mercury caused more than 95% inhibition of the molybdenum-reducing activity at 0.1 mM. The isolate was tentatively identified as Pseudomonas sp. strain DRY1 based on partial 16s rDNA molecular phylogenetic assessment and the Biolog microbial identification system. The characteristics of this strain would make it very useful in bioremediation works in the polar and temperate countries.

  9. Molybdate reduction to molybdenum blue by an Antarctic bacterium.

    Science.gov (United States)

    Ahmad, S A; Shukor, M Y; Shamaan, N A; Mac Cormack, W P; Syed, M A

    2013-01-01

    A molybdenum-reducing bacterium from Antarctica has been isolated. The bacterium converts sodium molybdate or Mo⁶⁺ to molybdenum blue (Mo-blue). Electron donors such as glucose, sucrose, fructose, and lactose supported molybdate reduction. Ammonium sulphate was the best nitrogen source for molybdate reduction. Optimal conditions for molybdate reduction were between 30 and 50 mM molybdate, between 15 and 20°C, and initial pH between 6.5 and 7.5. The Mo-blue produced had a unique absorption spectrum with a peak maximum at 865 nm and a shoulder at 710 nm. Respiratory inhibitors such as antimycin A, sodium azide, potassium cyanide, and rotenone failed to inhibit the reducing activity. The Mo-reducing enzyme was partially purified using ion exchange and gel filtration chromatography. The partially purified enzyme showed optimal pH and temperature for activity at 6.0 and 20°C, respectively. Metal ions such as cadmium, chromium, copper, silver, lead, and mercury caused more than 95% inhibition of the molybdenum-reducing activity at 0.1 mM. The isolate was tentatively identified as Pseudomonas sp. strain DRY1 based on partial 16s rDNA molecular phylogenetic assessment and the Biolog microbial identification system. The characteristics of this strain would make it very useful in bioremediation works in the polar and temperate countries.

  10. Targeting copper in cancer therapy: 'Copper That Cancer'.

    Science.gov (United States)

    Denoyer, Delphine; Masaldan, Shashank; La Fontaine, Sharon; Cater, Michael A

    2015-11-01

    Copper is an essential micronutrient involved in fundamental life processes that are conserved throughout all forms of life. The ability of copper to catalyze oxidation-reduction (redox) reactions, which can inadvertently lead to the production of reactive oxygen species (ROS), necessitates the tight homeostatic regulation of copper within the body. Many cancer types exhibit increased intratumoral copper and/or altered systemic copper distribution. The realization that copper serves as a limiting factor for multiple aspects of tumor progression, including growth, angiogenesis and metastasis, has prompted the development of copper-specific chelators as therapies to inhibit these processes. Another therapeutic approach utilizes specific ionophores that deliver copper to cells to increase intracellular copper levels. The therapeutic window between normal and cancerous cells when intracellular copper is forcibly increased, is the premise for the development of copper-ionophores endowed with anticancer properties. Also under investigation is the use of copper to replace platinum in coordination complexes currently used as mainstream chemotherapies. In comparison to platinum-based drugs, these promising copper coordination complexes may be more potent anticancer agents, with reduced toxicity toward normal cells and they may potentially circumvent the chemoresistance associated with recurrent platinum treatment. In addition, cancerous cells can adapt their copper homeostatic mechanisms to acquire resistance to conventional platinum-based drugs and certain copper coordination complexes can re-sensitize cancer cells to these drugs. This review will outline the biological importance of copper and copper homeostasis in mammalian cells, followed by a discussion of our current understanding of copper dysregulation in cancer, and the recent therapeutic advances using copper coordination complexes as anticancer agents.

  11. How the ``Blues'' reveals the intimacy of music and physics

    Science.gov (United States)

    Gibson, J. Murray

    2013-03-01

    Little do most people know when they hear blues piano - and you'll hear some live in this talk - that physics permeates the style, as it does all of music. Why should you care? By deconstructing blues piano the intimacy of physics, mathematics and music will be revealed in its glory.[1] The exercise says something about how the brains of the music composer and of the listener must be intimately linked to the physical principles of acoustics. And it provides a great vehicle to explain physical phenomena to non-scientists - everything from quantum mechanics to protein structure.

  12. Azide binding to the trinuclear copper center in laccase and ascorbate oxidase

    DEFF Research Database (Denmark)

    Gromov, I; Marchesini, A; Farver, O

    1999-01-01

    Azide binding to the blue copper oxidases laccase and ascorbate oxidase (AO) was investigated by electron paramagnetic resonance (EPR) and pulsed electron-nuclear double resonance (ENDOR) spectroscopies. As the laccase : azide molar ratio decreases from 1:1 to 1:7, the intensity of the type 2 (T2...

  13. Green synthesis of colloidal copper oxide nanoparticles using Carica papaya and its application in photocatalytic dye degradation

    Science.gov (United States)

    Sankar, Renu; Manikandan, Perumal; Malarvizhi, Viswanathan; Fathima, Tajudeennasrin; Shivashangari, Kanchi Subramanian; Ravikumar, Vilwanathan

    2014-03-01

    Copper oxide (CuO) nanoparticles were synthesized by treating 5 mM cupric sulphate with Carica papaya leaves extract. The kinetics of the reaction was studied using UV-visible spectrophotometry. An intense surface Plasmon resonance between 250-300 nm in the UV-vis spectrum clearly reveals the formation of copper oxide nanoparticles. The results of scanning electron microscopy (SEM) and dynamic light scattering (DLS) exhibited that the green synthesized copper oxide nanoparticles are rod in shape and having a mean particle size of 140 nm, further negative zeta potential disclose its stability at -28.9 mV. The Fourier-transform infrared (FTIR) spectroscopy results examined the occurrence of bioactive functional groups required for the reduction of copper ions. X-ray diffraction (XRD) spectra confirmed the copper oxide nanoparticles crystalline nature. Furthermore, colloidal copper oxide nanoparticles effectively degrade the Coomassie brilliant blue R-250 dye beneath the sunlight.

  14. Green synthesis of colloidal copper oxide nanoparticles using Carica papaya and its application in photocatalytic dye degradation.

    Science.gov (United States)

    Sankar, Renu; Manikandan, Perumal; Malarvizhi, Viswanathan; Fathima, Tajudeennasrin; Shivashangari, Kanchi Subramanian; Ravikumar, Vilwanathan

    2014-01-01

    Copper oxide (CuO) nanoparticles were synthesized by treating 5 mM cupric sulphate with Carica papaya leaves extract. The kinetics of the reaction was studied using UV-visible spectrophotometry. An intense surface Plasmon resonance between 250-300 nm in the UV-vis spectrum clearly reveals the formation of copper oxide nanoparticles. The results of scanning electron microscopy (SEM) and dynamic light scattering (DLS) exhibited that the green synthesized copper oxide nanoparticles are rod in shape and having a mean particle size of 140 nm, further negative zeta potential disclose its stability at -28.9 mV. The Fourier-transform infrared (FTIR) spectroscopy results examined the occurrence of bioactive functional groups required for the reduction of copper ions. X-ray diffraction (XRD) spectra confirmed the copper oxide nanoparticles crystalline nature. Furthermore, colloidal copper oxide nanoparticles effectively degrade the Coomassie brilliant blue R-250 dye beneath the sunlight.

  15. Luteolin Isolated from the Medicinal Plant Elsholtzia rugulosa (Labiatae Prevents Copper-Mediated Toxicity in β-Amyloid Precursor Protein Swedish Mutation Overexpressing SH-SY5Y Cells

    Directory of Open Access Journals (Sweden)

    Guanhua Du

    2011-03-01

    Full Text Available Luteolin, a 3’,4’,5,7-tetrahydroxyflavone, is a plant flavonoid and pharmacologically active agent that has been isolated from several plant species. In the present study, the effects of luteolin obtained from the medicinal plant Elsholtzia rugulosa and the related mechanisms were examined in an Alzheimer's disease (AD cell model. In this model, copper was used to exacerbate the neurotoxicity in β-amyloid precursor protein Swedish mutation stably overexpressed SH-SY5Y cells (named “APPsw cells” for short. Based on this model, we demonstrated that luteolin increased cell viability, reduced intracellular ROS generation, enhanced the activity of SOD and reversed mitochondrial membrane potential dissipation. Inhibition of caspase-related apoptosis was consistently involved in the neuroprotection afforded by luteolin. Furthermore, it down-regulated the expression of AβPP and lowered the secretion of Aβ1-42. These results indicated that luteolin from the Elsholtzia rugulosa exerted neroprotective effects through mechanisms that decrease AβPP expression, lower Aβ secretion, regulate the redox imbalance, preserve mitochondrial function, and depress the caspase family-related apoptosis.

  16. Excitation-Energy Transfer Paths from Tryptophans to Coordinated Copper Ions in Engineered Azurins: a Source of Observables for Monitoring Protein Structural Changes

    Science.gov (United States)

    Di Rocco, Giulia; Bernini, Fabrizio; Borsari, Marco; Martinelli, Ilaria; Bortolotti, Carlo Augusto; Battistuzzi, Gianantonio; Ranieri, Antonio; Caselli, Monica; Sola, Marco; Ponterini, Glauco

    2016-09-01

    The intrinsic fluorescence of recombinant proteins offers a powerful tool to detect and characterize structural changes induced by chemical or biological stimuli. We show that metal-ion binding to a hexahistidine tail can significantly broaden the range of such structurally sensitive fluorescence observables. Bipositive metal-ions as Cu2+, Ni2+ and Zn2+ bind 6xHis-tag azurin and its 6xHis-tagged R129W and W48A-R129W mutants with good efficiency and, thereby, quench their intrinsic fluorescence. Due to a much more favourable spectral overlap, the 6xHis-tag/Cu2+ complex(es) are the most efficient quenchers of both W48 and W129 emissions. Based on simple Förster-type dependence of energy-transfer efficiency on donor/acceptor distance, we can trace several excitation-energy transfer paths across the protein structure. Unexpected lifetime components in the azurin 6xHis-tag/Cu2+ complex emission decays reveal underneath complexity in the conformational landscape of these systems. The new tryptophan emission quenching paths provide additional signals for detecting and identifying protein structural changes.

  17. Protein nanopore-based, single-molecule exploration of copper binding to an antimicrobial-derived, histidine-containing chimera peptide.

    Science.gov (United States)

    Mereuta, Loredana; Schiopu, Irina; Asandei, Alina; Park, Yoonkyung; Hahm, Kyung-Soo; Luchian, Tudor

    2012-12-11

    Metal ions binding exert a crucial influence upon the aggregation properties and stability of peptides, and the propensity of folding in various substates. Herein, we demonstrate the use of the α-HL protein as a powerful nanoscopic tool to probe Cu(2+)-triggered physicochemical changes of a 20 aminoacids long, antimicrobial-derived chimera peptide with a His residue as metal-binding site, and simultaneously dissect the kinetics of the free- and Cu(2+)-bound peptide interaction to the α-HL pore. Combining single-molecule electrophysiology on reconstituted lipid membranes and fluorescence spectroscopy, we show that the association rate constant between the α-HL pore and a Cu(2+)-free peptide is higher than that of a Cu(2+)-complexed peptide. We posit that mainly due to conformational changes induced by the bound Cu(2+) on the peptide, the resulting complex encounters a higher energy barrier toward its association with the protein pore, stemming most likely from an extra entropy cost needed to fit the Cu(2+)-complexed peptide within the α-HL lumen region. The lower dissociation rate constant of the Cu(2+)-complexed peptide from α-HL pore, as compared to that of Cu(2+)-free peptide, supports the existence of a deeper free energy well for the protein interaction with a Cu(2+)-complexed peptide, which may be indicative of specific Cu(2+)-mediated contributions to the binding of the Cu(2+)-complexed peptide within the pore lumen.

  18. Agminated blue nevus - Case report*

    Science.gov (United States)

    Lisboa, Alice Paixão; Silvestre, Keline Jácome; Pedreira, Renata Leite; Alves, Natália Ribeiro de Magalhães; Obadia, Daniel Lago; Azulay-Abulafia, Luna

    2016-01-01

    Blue nevi are benign melanocytic lesions located in the deeper reticular dermis, consequence of failure of melanocytic migration into the dermal-epidermal junction from the neural crest. Lesions are usually asymptomatic and solitary, but may present in a multiple or agminated (grouped) pattern. The agminated subtype is formed when bluish-pigmented lesions cluster together in a well-defined area. Lesions can be flat or raised. We report the case of a patient who presented multiple bluish macules (1-3 mm in diameter) grouped on the left upper back. Dermoscopy and anatomic pathological examination were consistent with blue nevus. PMID:27828645

  19. LEP copper accelerating cavities

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    These copper cavities were used to generate the radio frequency electric field that was used to accelerate electrons and positrons around the 27-km Large Electron-Positron (LEP) collider at CERN, which ran from 1989 to 2000. The copper cavities were gradually replaced from 1996 with new superconducting cavities allowing the collision energy to rise from 90 GeV to 200 GeV by mid-1999.

  20. Copper wire bonding

    CERN Document Server

    Chauhan, Preeti S; Zhong, ZhaoWei; Pecht, Michael G

    2014-01-01

    This critical volume provides an in-depth presentation of copper wire bonding technologies, processes and equipment, along with the economic benefits and risks.  Due to the increasing cost of materials used to make electronic components, the electronics industry has been rapidly moving from high cost gold to significantly lower cost copper as a wire bonding material.  However, copper wire bonding has several process and reliability concerns due to its material properties.  Copper Wire Bonding book lays out the challenges involved in replacing gold with copper as a wire bond material, and includes the bonding process changes—bond force, electric flame off, current and ultrasonic energy optimization, and bonding tools and equipment changes for first and second bond formation.  In addition, the bond–pad metallurgies and the use of bare and palladium-coated copper wires on aluminum are presented, and gold, nickel and palladium surface finishes are discussed.  The book also discusses best practices and re...

  1. Copper Induces Apoptosis of Neuroblastoma Cells Via Post-translational Regulation of the Expression of Bcl-2-family Proteins and the tx Mouse is a Better Model of Hepatic than Brain Cu Toxicity.

    Science.gov (United States)

    Chan, Hsien W; Liu, Tianbing; Verdile, Giuseppe; Bishop, Glenda; Haasl, Ryan J; Smith, Mark A; Perry, George; Martins, Ralph N; Atwood, Craig S

    2008-01-01

    The basic mechanism(s) by which altered Cu homeostasis is toxic to hepatocytes and neurons, the two major cell types affected in copper storage diseases such as Wilson's disease (WD), remain unclear. Using human M17 neuroblastoma cells as a model to examine Cu toxicity, we found that there was a time- and concentration-dependent induction of neuronal death, such that at 24 h there was a approximately 50 % reduction in viability with 25 muM Cu-glycine(2). Cu-glycine(2) (25:50 muM) treatment for 24 h significantly altered the expression of 296 genes, including 8 genes involved with apoptosis (BCL2-associated athanogene 3, BCL2/adenovirus E1B 19kDa interacting protein caspase 5, regulator of Fas-induced apoptosis, V-jun sarcoma virus 17 oncogene homolog, claudin 5, prostaglandin E receptor 3 and protein tyrosine phosphatase, non-receptor type 6). Surprisingly, changes in the expression of more 'traditional' apoptotic genes (Bcl-2, Bax, Bak and Bad) did not vary more than 20 %. To test whether the induction of apoptosis in neuroblastoma cells was via post-translational mechanisms, we measured the protein expression of these apoptotic markers in M17 neuroblastoma cells treated with Cu-glycine(2) (0-100 muM) for 24-48 h. Compared with glycine treated cells, Cu-glycine(2) reduced Bcl-2 expression by 50 %, but increased Bax and Bak expression by 130% and 400 %, respectively. To assess whether Cu also induced apoptotic cell death in a mouse model of WD, we measured the expression of these apoptotic markers in the liver and brain of mice expressing an ATP7b gene mutation (tx(J) mice) at 10 months of age (near the end of their lives when overt liver pathology is displayed). Changes in the liver expression of these apoptotic markers in tx(J) mice compared to background mice mirrored those of Cu treated neuroblastoma cells. In contrast, few changes in apoptotic protein expression were detected in the brain between tx(J) and background mice, indicating the tx(J) mouse is a good

  2. MEDNIK syndrome: a novel defect of copper metabolism treatable by zinc acetate therapy.

    Science.gov (United States)

    Martinelli, Diego; Travaglini, Lorena; Drouin, Christian A; Ceballos-Picot, Irene; Rizza, Teresa; Bertini, Enrico; Carrozzo, Rosalba; Petrini, Stefania; de Lonlay, Pascale; El Hachem, Maya; Hubert, Laurence; Montpetit, Alexandre; Torre, Giuliano; Dionisi-Vici, Carlo

    2013-03-01

    MEDNIK syndrome-acronym for mental retardation, enteropathy, deafness, neuropathy, ichthyosis, keratodermia-is caused by AP1S1 gene mutations, encoding σ1A, the small subunit of the adaptor protein 1 complex, which plays a crucial role in clathrin coat assembly and mediates trafficking between trans-Golgi network, endosomes and the plasma membrane. MEDNIK syndrome was first reported in a few French-Canadian families sharing common ancestors, presenting a complex neurocutaneous phenotype, but its pathogenesis is not completely understood. A Sephardic-Jewish patient, carrying a new AP1S1 homozygous mutation, showed severe perturbations of copper metabolism with hypocupremia, hypoceruloplasminemia and liver copper accumulation, along with intrahepatic cholestasis. Zinc acetate treatment strikingly improved clinical conditions, as well as liver copper and bile-acid overload. We evaluated copper-related metabolites and liver function retrospectively in the original French-Canadian patient series. Intracellular copper metabolism and subcellular localization and function of copper pump ATP7A were investigated in patient fibroblasts. Copper metabolism perturbation and hepatopathy were confirmed in all patients. Studies in mutant fibroblasts showed abnormal copper incorporation and retention, reduced expression of copper-dependent enzymes cytochrome-c-oxidase and Cu/Zn superoxide dismutase, and aberrant intracellular trafficking of Menkes protein ATP7A, which normalized after rescue experiments expressing wild-type AP1S1 gene. We solved the pathogenetic mechanism of MEDNIK syndrome, demonstrating that AP1S1 regulates intracellular copper machinery mediated by copper-pump proteins. This multisystem disease is characterized by a unique picture, combining clinical and biochemical signs of both Menkes and Wilson's diseases, in which liver copper overload is treatable by zinc acetate therapy, and can now be listed as a copper metabolism defect in humans. Our results may also

  3. Carotenoid metabolic profiling and transcriptome-genome mining reveal functional equivalence among blue-pigmented copepods and appendicularia

    KAUST Repository

    Mojib, Nazia

    2014-06-01

    The tropical oligotrophic oceanic areas are characterized by high water transparency and annual solar radiation. Under these conditions, a large number of phylogenetically diverse mesozooplankton species living in the surface waters (neuston) are found to be blue pigmented. In the present study, we focused on understanding the metabolic and genetic basis of the observed blue phenotype functional equivalence between the blue-pigmented organisms from the phylum Arthropoda, subclass Copepoda (Acartia fossae) and the phylum Chordata, class Appendicularia (Oikopleura dioica) in the Red Sea. Previous studies have shown that carotenoid–protein complexes are responsible for blue coloration in crustaceans. Therefore, we performed carotenoid metabolic profiling using both targeted and nontargeted (high-resolution mass spectrometry) approaches in four different blue-pigmented genera of copepods and one blue-pigmented species of appendicularia. Astaxanthin was found to be the principal carotenoid in all the species. The pathway analysis showed that all the species can synthesize astaxanthin from β-carotene, ingested from dietary sources, via 3-hydroxyechinenone, canthaxanthin, zeaxanthin, adonirubin or adonixanthin. Further, using de novo assembled transcriptome of blue A. fossae (subclass Copepoda), we identified highly expressed homologous β-carotene hydroxylase enzymes and putative carotenoid-binding proteins responsible for astaxanthin formation and the blue phenotype. In blue O. dioica (class Appendicularia), corresponding putative genes were identified from the reference genome. Collectively, our data provide molecular evidences for the bioconversion and accumulation of blue astaxanthin–protein complexes underpinning the observed ecological functional equivalence and adaptive convergence among neustonic mesozooplankton.

  4. Proteomics meets blue biotechnology: a wealth of novelties and opportunities.

    Science.gov (United States)

    Hartmann, Erica M; Durighello, Emie; Pible, Olivier; Nogales, Balbina; Beltrametti, Fabrizio; Bosch, Rafael; Christie-Oleza, Joseph A; Armengaud, Jean

    2014-10-01

    Blue biotechnology, in which aquatic environments provide the inspiration for various products such as food additives, aquaculture, biosensors, green chemistry, bioenergy, and pharmaceuticals, holds enormous promise. Large-scale efforts to sequence aquatic genomes and metagenomes, as well as campaigns to isolate new organisms and culture-based screenings, are helping to push the boundaries of known organisms. Mass spectrometry-based proteomics can complement 16S gene sequencing in the effort to discover new organisms of potential relevance to blue biotechnology by facilitating the rapid screening of microbial isolates and by providing in depth profiles of the proteomes and metaproteomes of marine organisms, both model cultivable isolates and, more recently, exotic non-cultivable species and communities. Proteomics has already contributed to blue biotechnology by identifying aquatic proteins with potential applications to food fermentation, the textile industry, and biomedical drug development. In this review, we discuss historical developments in blue biotechnology, the current limitations to the known marine biosphere, and the ways in which mass spectrometry can expand that knowledge. We further speculate about directions that research in blue biotechnology will take given current and near-future technological advancements in mass spectrometry.

  5. Role of the P-Type ATPases, ATP7A and ATP7B in brain copper homeostasis

    OpenAIRE

    Jonathon eTelianidis; Ya Hui eHung; Stephanie eMateria; Sharon eLa Fontaine

    2013-01-01

    Over the past two decades there have been significant advances in our understanding of copper homeostasis and the pathological consequences of copper dysregulation. Cumulative evidence is revealing a complex regulatory network of proteins and pathways that maintain copper homeostasis. The recognition of copper dysregulation as a key pathological feature in prominent neurodegenerative disorders such as Alzheimer’s, Parkinson’s, and prion diseases has led to increased research focus on the mech...

  6. Digestibilidade e retenção de nitrogênio de alimentos para papagaios verdadeiros (Amazona aestiva Digestibility and protein retention of foods for blue-fronted parrot (Amazona aestiva

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo do Prado Saad

    2007-10-01

    nitrogênio para papagaios.Were used 34 blue fronted parrot, distributed in blocks with 17 treatments (T1 - reference diet, T2 - sunflower seed, T3 - oat, T4 - egg yolk, T5 - integral egg, T6 - egg white, T7 - wheat germen, T8 - wheat bran, T9 - triturated corn, T10 - jellied corn, T11 - sunflower bran, T12 - yeast, T13 - citric pulp, T14 - papaya, T15 - banana, T16 - soy bran, T17 - extruded soy during three periods, totaling six repetitions (102 experimental units. For foods evaluation the substitution methodology was used. They were appraised the digestibility coefficients of the dry matter (DM and organic matter (OM and the protein retention of the evaluated foods. Were compared the treatments two to 17. The treatment 1 (reference diet it was just used for the substitution calculations, not being part of the statistical analyses. The averages were compared by the test Scott-Knott. The obtained results allowed to conclude that: 1 - foods as the jellied corn, the egg yolk and the sunflower seed, as well as the oat, integral egg, triturated corn, papaya and banana, they possess high DM and OM digestibility for parrots, could be considered as good choice options for the composition of a complete diet; 2 - foods as the citric pulp and the sunflower bran presented low apparent and true digestibility of the DM and OM and they should be used in low levels and with moderation in the formulation of rations for these birds; 3 - the true nitrogen retention was positive for all the birds, what suggests that the same ones can be depositing still tissues, however, due to the high variation coefficient, this measured it seems not to be adapted to express the real nitrogen retention coefficient for parrots.

  7. Standard Specification for Copper-Aluminum-Silicon-Cobalt Alloy, Copper-Nickel-Silicon-Magnesium Alloy, Copper-Nickel-Silicon Alloy, Copper-Nickel-Aluminum-Magnesium Alloy, and Copper-Nickel-Tin Alloy Sheet and Strip

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    Standard Specification for Copper-Aluminum-Silicon-Cobalt Alloy, Copper-Nickel-Silicon-Magnesium Alloy, Copper-Nickel-Silicon Alloy, Copper-Nickel-Aluminum-Magnesium Alloy, and Copper-Nickel-Tin Alloy Sheet and Strip

  8. Blue Ocean vs. Five Forces

    NARCIS (Netherlands)

    A.E. Burke (Andrew); A.J. van Stel (André); A.R. Thurik (Roy)

    2010-01-01

    textabstractThe article reports on the authors' research in the Netherlands which focused on a profit model in Dutch retail stores and a so-called blue-ocean approach which requires a new market that attracts consumers and increases profits. Topics include the competitive strategy approach to increa

  9. Blue rubber bleb naevus syndrome

    DEFF Research Database (Denmark)

    Lybecker, Martin Bell; Stawowy, Marek; Clausen, Niels

    2016-01-01

    Blue rubber bleb naevus syndrome (BRBNS) is a rare vascular disorder with malformed veins, or blebs, appearing in the skin or internal organs. Gastrointestinal tract involvement is the most common feature and often subject to bleeding, potentially resulting in chronic occult blood loss and iron...

  10. The blue revolution in asia

    DEFF Research Database (Denmark)

    Jespersen, Karen Sau; Ponte, Stefano; Kelling, Ingrid

    2014-01-01

    In this article, we examine the upgrading trajectories of selected aquaculture value chains in four Asian countries and the links between upgrading and three factors of value chain governance: coordination mechanisms; types of drivers; and domestic regulation. We find instances of improving produ...... of upgrading the "blue revolution" in Asia...

  11. Cadmium versus copper toxicity: Insights from an integrated dissection of protein synthesis pathway in the digestive glands of mussel Mytilus galloprovincialis

    Energy Technology Data Exchange (ETDEWEB)

    Pytharopoulou, S.; Kournoutou, G.G. [Laboratory of Biochemistry, School of Medicine, University of Patras, 26504 Patras (Greece); Leotsinidis, M. [Laboratory of Public Health, School of Medicine, University of Patras, 26504 Patras (Greece); Georgiou, C.D. [Department of Biology, Section of Genetics, Cell Biology and Development, University of Patras, 26504 Patras (Greece); Kalpaxis, D.L., E-mail: dimkal@med.upatras.gr [Laboratory of Biochemistry, School of Medicine, University of Patras, 26504 Patras (Greece)

    2013-09-15

    Highlights: • Cu{sup 2+}-exposure of mussels results in genotoxicity, without affecting MTs production. •Cd{sup 2+}-exposure of mussels causes low genotoxicity, but induces MTs production. • Both metals induce oxidative stress in mussels, with Cd being the strongest inducer. • Translation is suppressed by both metals, mainly at the initiation and elongation steps. • MTs abrogate translational defects caused by Cd{sup 2+}, by trapping the toxic metal. -- Abstract: The main purpose of this study was to investigate the impact of metal-mediated stress on the protein-synthesis pathway in mussels. To this end, mussels (Mytilus galloprovincialis) underwent a 15 days exposure to 100 μg/L Cu{sup 2+} or Cd{sup 2+}. Both metals, in particular Cd{sup 2+}, accumulated in mussel digestive glands and generated a specific status of oxidative-stress. Exposure of mussels to each metal resulted in 40% decrease of the tRNA-aminoacylation efficiency, at the end of exposure. Cu{sup 2+} also caused a progressive loss in the capability of 40S-ribosomal subunits to form 48S pre-initiation complex, which reached 34% of the control at the end of exposure. Other steps of translation underwent less pronounced, but measurable damages. Mussels exposed to Cd{sup 2+} for 5 days presented a similar pattern of translational dysfunctions in digestive glands, but during the following days of exposure the ribosomal efficiency was gradually restored. Meanwhile, metallothionein levels significantly increased, suggesting that upon Cd{sup 2+}-mediated stress the protein-synthesizing activity was reorganized both quantitatively and qualitatively. Conclusively, Cd{sup 2+} and Cu{sup 2+} affect translation at several levels. However, the pattern of translational responses differs, largely depending on the capability of each metal to affect cytotoxic pathways in the tissues, such as induction of antioxidant defense and specific repair mechanisms.

  12. Green synthesis of copper nanoparticles for the efficient removal (degradation) of dye from aqueous phase.

    Science.gov (United States)

    Sinha, Tanur; Ahmaruzzaman, M

    2015-12-01

    The present work reports the utilization of a common household waste material (fish scales of Labeo rohita) for the synthesis of copper nanoparticles. The method so developed was found to be green, environment-friendly, and economic. The fish scale extracts were acting as a stabilizing and reducing agents. This method avoids the use of external reducing and stabilizing agents, templates, and solvents. The compositional abundance of gelatin may be envisaged for the effective reductive as well as stabilizing potency. The mechanisms for the formation of nanoparticles have also been presented. The synthesized copper nanoparticles formed were predominantly spherical in nature with an average size of nanoparticles in the range of 25-37 nm. The copper nanoparticles showed characteristic Bragg's reflection planes of fcc which was supported by both selected area electron diffraction and X-ray diffraction pattern and showed surface plasmon resonance at 580 nm. Moreover, the energy dispersive spectroscopy pattern also revealed the presence of only elemental copper in the copper nanoparticles. The prepared nanoparticles were used for the remediation of a carcinogenic and noxious textile dye, Methylene blue, from aqueous solution. Approximately, 96 % degradation of Methylene blue dye was observed within 135 min using copper nanoparticles. The probable mechanism for the degradation of the dye has been presented, and the degraded intermediates have been identified using the liquid chromatography-mass spectroscopy technique. The high efficiency of nanoparticles as photocatalysts has opened a promising application for the removal of hazardous dye from industrial effluents contributing indirectly to environmental cleanup process.

  13. Zinc, copper and selenium in reproduction.

    Science.gov (United States)

    Bedwal, R S; Bahuguna, A

    1994-07-15

    Of the nine biological trace elements, zinc, copper and selenium are important in reproduction in males and females. Zinc content is high in the adult testis, and the prostate has a higher concentration of zinc than any other organ of the body. Zinc deficiency first impairs angiotensin converting enzyme (ACE) activity, and this in turn leads to depletion of testosterone and inhibition of spermatogenesis. Defects in spermatozoa are frequently observed in the zinc-deficient rat. Zinc is thought to help to extend the functional life span of the ejaculated spermatozoa. Zinc deficiency in the female can lead to such problems as impaired synthesis/secretion of (FSH) and (LH), abnormal ovarian development, disruption of the estrous cycle, frequent abortion, a prolonged gestation period, teratogenicity, stillbirths, difficulty in parturition, pre-eclampsia, toxemia and low birth weights of infants. The level of testosterone in the male has been suggested to play a role in the severity of copper deficiency. Copper-deficient female rats are protected against mortality due to copper deficiency, and the protection has been suggested to be provided by estrogens, since estrogens alter the subcellular distribution of copper in the liver and increase plasma copper levels by inducing ceruloplasmin synthesis. The selenium content of male gonads increases during pubertal maturation. Selenium is localized in the mitochondrial capsule protein (MCP) of the midpiece. Maximal incorporation in MCP occurs at steps 7 and 12 of spermatogenesis and uptake decreases by step 15. Selenium deficiency in females results in infertility, abortions and retention of the placenta. The newborns from a selenium-deficient mother suffer from muscular weakness, but the concentration of selenium during pregnancy does not have any effect on the weight of the baby or length of pregnancy. The selenium requirements of a pregnant and lactating mother are increased as a result of selenium transport to the fetus via

  14. Effects of cyclodextrins on the structure of LDL and its susceptibility to copper-induced oxidation.

    Science.gov (United States)

    Ao, Meiying; Gan, Chaoye; Shao, Wenxiang; Zhou, Xing; Chen, Yong

    2016-08-25

    Cyclodextrins (CDs) have long been widely used as drug/food carriers and were recently developed as drugs for the treatment of diseases (e.g. Niemann-Pick C1 and cancers). It is unknown whether cyclodextrins may influence the structure of low-density lipoprotein (LDL), its susceptibility to oxidation, and atherogenesis. In this study, four widely used cyclodextrins including α-CD, γ-CD, and two derivatives of β-CD (HPβCD and MβCD) were recruited. Interestingly, agarose gel electrophoresis (staining lipid and protein components of LDL with Sudan Black B and Coomassie brilliant blue, respectively but simultaneously) shows that cyclodextrins at relatively high concentrations caused disappearance of the LDL band and/or appearance of an additional protein-free lipid band, implying that cyclodextrins at relatively high concentrations can induce significant electrophoresis-detectable lipid depletion of LDL. Atomic force microscopy (AFM) detected that MβCD (as a representative of cyclodextrins) induced size decrease of LDL particles in a dose-dependent manner, further confirming the lipid depletion effects of cyclodextrins. Moreover, the data from agarose gel electrophoresis, conjugated diene formation, MDA production, and amino group blockage of copper-oxidized LDL show that cyclodextrins can impair LDL susceptibility to oxidation. It implies that cyclodextrins probably help to inhibit atherogenesis by lowering LDL oxidation.

  15. Blue light does not impair wound healing in vitro.

    Science.gov (United States)

    Masson-Meyers, Daniela Santos; Bumah, Violet Vakunseh; Enwemeka, Chukuka Samuel

    2016-07-01

    Irradiation with red or near infrared light promotes tissue repair, while treatment with blue light is known to be antimicrobial. Consequently, it is thought that infected wounds could benefit more from combined blue and red/infrared light therapy; but there is a concern that blue light may slow healing. We investigated the effect of blue 470nm light on wound healing, in terms of wound closure, total protein and collagen synthesis, growth factor and cytokines expression, in an in vitro scratch wound model. Human dermal fibroblasts were cultured for 48h until confluent. Then a linear scratch wound was created and irradiated with 3, 5, 10 or 55J/cm(2). Control plates were not irradiated. Following 24h of incubation, cells were fixed and stained for migration and fluorescence analyses and the supernatant collected for quantification of total protein, hydroxyproline, bFGF, IL-6 and IL-10. The results showed that wound closure was similar for groups treated with 3, 5 and 10J/cm(2), with a slight improvement with the 5J/cm(2) dose, and slower closure with 55J/cm(2) plight at low fluence does not impair in vitro wound healing. The significant decrease in IL-6 suggests that 470nm light is anti-inflammatory.

  16. Non-ceruloplasmin bound copper and ATP7B gene variants in Alzheimer's disease.

    Science.gov (United States)

    Squitti, R; Siotto, M; Arciello, M; Rossi, L

    2016-09-01

    ATP7B, a protein mainly expressed in the hepatocytes, is a copper chaperone that loads the metal into the serum copper-protein ceruloplasmin during its synthesis and also escorts superfluous copper into the bile, by a sophisticated trafficking mechanism. Impaired function of this ATPase is associated with a well-known inborn error of copper metabolism, Wilson's disease (WD). Several mutations of ATP7B are known, involving different regions of the protein, thus resulting in a plethora of phenotypes in WD patients. It is a consolidated notion that copper dysmetabolism occurs in Alzheimer's disease (AD) as well. Besides the molecular mechanisms relating copper to the protein hallmarks of this disease and neurodegeneration, more recently the observation that a free-copper in the serum, not bound to ceruloplasmin (non-Cp-Cu), characterizes AD patients, prompted our research to identify possible genetic defects of the ATP7B gene in AD patients. Four specific single nucleotide polymorphisms and a WD rare mutation have a statistical association with AD. They contribute to characterize a copper subtype of AD. Additional facets of this AD phenotype, typified by higher levels of non-Cp-Cu, are presented and discussed in the framework of copper failure as an accelerator risk factor of neurological disorders with different aetiology.

  17. QCD-inspired spectra from Blue`s functions

    Energy Technology Data Exchange (ETDEWEB)

    Nowak, M.A. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik]|[Uniwersytet Jagiellonski, Cracow (Poland). Dept. of Theoretical Physics; Papp, G. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Lorand Eoetvoes Univ., Budapest (Hungary). Inst. for Theoretical Physics; Zahed, I. [State Univ. of New York, Stony Brook, NY (United States). Dept. of Physics

    1996-03-01

    We use the law of addition in random matrix theory to analyze the spectral distributions of a variety of chiral random matrix models as inspired from QCD whether by symmetries or models. In terms of the Blue`s functions recently discussed by Zee, we show that most of the spectral distributions in the macroscopic limit and the quenched approximation, follow algebraically from the discontinuity of a pertinent solution to a cubic (Cardano) or a quartic (Ferrari) equation. We use the end-point equation of the energy spectra in chiral random matrix models to argue for novel phase structures, in which the Dirac density of states plays the role of an order parameter. (orig.)

  18. Jiangxi Copper Plans to Increase its Refined Copper Output

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>According to news published on March 30th, China’s largest copper producer--Jiangxi Copper alleged in its 2010 Financial Report Statement that it plans to improve its output of refined copper by 4.4% in 2011, to increase from 900,000 tonnes last year to 940,000 tons.

  19. 低蛋白质饲粮中添加蛋氨酸对冬毛期蓝狐生产性能、营养物质消化率及氮代谢的影响%Effects of Methionine Supplementation in Low-Protein Diets on Performance, Nutrient Digestibility and Nitrogen Metabolism of Blue Foxes during the Winter Hair Period

    Institute of Scientific and Technical Information of China (English)

    郭俊刚; 张铁涛; 崔虎; 高秀华; 杨福合; 邢秀梅

    2014-01-01

    This experiment was conducted to study the effects of methionine supplementation in low-protein di-ets on performance, nutrient digestibility and nitrogen metabolism of blue foxes during the winter hair period. One hundred and five healthy male blue foxes at the age of 25 weeks with an average body weight of (4. 88±0. 60) kg were randomly assigned into 7 groups with 15 replicates per group and 1 fox per replicate. The blue foxes in positive control group were fed a 28% protein level basal diet, and those in negative control group were fed a 26% protein level basal diet. The blue foxes in experimental groups were fed low-protein diets (26% protein level basal diets) supplemented with 0. 2%, 0. 4%, 0. 6%, 0. 8% and 1. 0% methionine, re-spectively. The pre-test lasted for 7 days and the formal test lasted for 80 days. The results showed as follows:the final body weight, average daily gain and feed conversion rate in 0 . 6% methionine group were extremely significantly higher than those in negative control group and 0 . 2% methionine group ( P0 . 05 ) , but significantly longer than that in 0 . 2%, 0 . 4% and 0 . 8% methionine groups and positive control group ( P0 . 05 ) , but significantly or extremely significantly higher than that in negative control group ( P0 . 05 ) , but extremely significantly higher than that in 0 . 2%, 0 . 4% and 1 . 0% methionine groups and negative control group ( P0 . 05 ) , but significantly higher than those in 1. 0% methionine group and negative control group (P0.05)。0.6%蛋氨酸组干物质消化率、粗蛋白质消化率及粗脂肪消化率与正对照组相比差异不显著(P >0.05),但显著或极显著高于负对照组(P0.05);0.6%蛋氨酸组净蛋白质利用率和蛋白质生物学价值显著高于1.0%蛋氨酸组和负对照组(P0.05)。综合本试验各项测定指标,在蛋白质水平为26%的低蛋白质饲粮中添加0.6%的蛋氨酸,即饲粮中蛋氨酸水平为0.99%时,能够满足冬毛期蓝狐对蛋氨酸

  20. Decreased scattering coefficient of blue sclerae

    NARCIS (Netherlands)

    Lanting, P J; Borsboom, P C; te Meerman, G J; ten Kate, L P

    1985-01-01

    The optical scattering properties of blue and normal sclerae were studied with a fiber optic scattering monitor. The scattering was clearly reduced in two osteogenesis imperfecta patients with blue sclerae, and low normal in one osteogenesis imperfecta patient without blue sclerae.

  1. [Copper metabolism and genetic disorders].

    Science.gov (United States)

    Shimizu, Norikazu

    2016-07-01

    Copper is one of essential trace elements. Copper deficiency lead to growth and developmental failure and/or neurological dysfunction. However, excess copper is also problems for human life. There are two disorders of inborn error of copper metabolism, Menkes disease and Wilson disease. Menkes disease is an X linked recessive disorder with copper deficiency and Wilson disease is an autosomal recessive disorder with copper accumulation. These both disorders result from the defective functioning of copper transport P-type ATPase, ATP7A of Menkes disease and ATP7B of Wilson disease. In this paper, the author describes about copper metabolism of human, and clinical feature, diagnosis and treatment of Menkes disease and Wilson disease.

  2. Synthesis,DNA/protein Interaction of a Copper(II)Complex with Schiff▬base Ligand%席夫碱铜配合物合成及与DNA/蛋白质作用的研究

    Institute of Scientific and Technical Information of China (English)

    李梅; 黄书娟; 叶诚; 黄珊珊

    2014-01-01

    A novel copper( II)complex was prepared by pyridine▬2▬aldehyde and N,N▬dimethylethylenediamine,and characterized by single▬crystal X▬ray diffraction,elemental analysis,and ESI▬MS• Single▬crystal analysis revealed that the complex shows a distorted pseudo▬square▬pyramidal geometry• The binding properties of the complex with calf thymus DNA( CT▬DNA)and HSA were investiga▬ted by UV▬visible( UV▬vis),uorescence and circular dichroism( CD)spectra• The complex binds signicantly to CT▬DNA by intercala▬tion modes,and the complex binding to protein HSA belongs to static quenching mechanism• The interaction between the complex and HSA involve hydrogen bonding and weak van der Waals•%利用2-吡啶甲醛、N,N▬二甲基乙二胺制备了一种新的席夫碱铜配合物,并通过X▬射线单晶衍射、元素分析和ESI▬MS对其结构进行分析•晶体结构分析表明,配合物呈现扭曲的四方锥构型•用紫外▬可见吸收光谱、荧光光谱和圆二色光谱研究了配合物与小牛胸腺DNA( CT▬DNA)和人血清白蛋白( HSA)的结合性质•结果表明:配合物以插入的方式与DNA相互作用,且配合物与HSA的相互作用为静态猝灭机制,分子间作用力为氢键和范德华力•

  3. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation.

    Science.gov (United States)

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

  4. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

    Science.gov (United States)

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

  5. Status of Blue Ridge Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Blue Ridge Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports and data available, as well as interview with water resource professionals in various federal, state, and local agencies. Blue Ridge Reservoir is a single-purpose hydropower generating project. When consistent with this primary objective, the reservoir is also operated to benefit secondary objectives including water quality, recreation, fish and aquatic habitat, development of shoreline, aesthetic quality, and other public and private uses that support overall regional economic growth and development. 8 refs., 1 fig.

  6. Thermoluminescence (TL) of Egyptian Blue

    Energy Technology Data Exchange (ETDEWEB)

    Schvoerer, M.; Delavergne, M.-C.; Chapoulie, R.

    1988-01-01

    Egyptian Blue is a synthesized crystalline pictorial pigment with formula CaCuSi/sub 4/O/sub 10/. It has been used in Egypt and Mesopotamia from the 3rd millenium B.C. A preliminary experiment on a recently synthesized sample showed that this pigment is thermoluminescent after ..beta.. irradiation (/sup 90/Sr). As the signal intensity grows linearly with the administered dose within the temperature range commonly used in TL dating, we have been looking for this phenomenon from archaeological pigments. It was encountered with two samples found in excavation. From its intensity and stability we concluded that Egyptian Blue can be dated using TL. This first and positive result encouraged us to extend the method to other types of mineral pigments synthesized by early man, and to suggest that it may be used for direct dating of ancient murals.

  7. The Physics of the Blues

    Science.gov (United States)

    Gibson, J. Murray

    2009-03-01

    In looking at the commonalities between music and science, one sees that the musician's palette is based on the principles of physics. The pitch of a musical note is determined by the frequency of the sound wave. The scales that musicians use to create and play music can be viewed as a set of rules. What makes music interesting is how musicians develop those rules and create ambiguity with them. I will discuss the evolution of western musical scales in this context. As a particular example, ``Blue'' notes are very harmonic notes that are missing from the equal temperament scale. The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting. Live keyboard demonstrations will be used. Beyond any redeeming entertainment value the talk will emphasize the serious connections between science and art in music. Nevertheless tips will be accepted.

  8. Using XAS and SXRF to Study Copper in Wilson Disease at the Molecular and Tissue Level

    Science.gov (United States)

    Ralle, Martina; Blackburn, Ninian J.; Lutsenko, Svetlana

    2007-02-01

    Wilson disease (WD) is a genetic disorder of copper metabolism associated with severe hepatic, neurological, and psychiatric abnormalities. In WD, the billiary copper excretion is impaired and copper accumulates in tissues, particularly in the liver and the brain. The affected gene, ATP7B, encodes the copper transporting ATPase, Wilson disease protein (WNDP). WNDP has six copper binding sites in the N-terminal portion of the molecule. Each site includes the conserved amino acid sequence MXCXXC, and binds 1 Cu(I) through its 2 cysteine residues. We performed X-ray absorption studies at the Cu Kα-edge on the recombinant N-terminal domain of WNDP (N-WNDP). Copper was bound to N-WNDP either in vivo or in vitro in the presence of different reducing agents. We found that in N-WNDP copper is predominantly coordinated in a linear fashion by two cysteines, with the appearance of a Cu-Cu interaction when all metal binding sites are filled. Increasing amounts of reducing agents containing sulfide or phosphine groups led to binding of the exogenous ligands to copper thereby increasing the coordination number of copper from two to three. To better understand the role of copper in WD, we utilized livers of the 6-weeks-old Atp7b-/- mice (an animal model for WD) in which the copper concentration was 10-20-fold higher compared to that of the control mice. The distribution of copper in hepatocytes was evaluated by synchrotron based X-ray fluorescence microprobe (SXRF). We demonstrate that we can prepare liver slices that retain copper and can detect copper with subcellular resolution. On the same sections μ-XANES (spot size: 5 micron) was used to determine the oxidation state of copper.

  9. Uso do Blue Rayon para extração/concentração de compostos policíclicos em amostras ambientais

    Directory of Open Access Journals (Sweden)

    Kummrow Fábio

    2006-01-01

    Full Text Available This is a review about the use of Blue rayon in the extraction and concentration of environmental contaminants in the aquatic environment. Blue rayon is an adsorbent composed of fibers covalently linked with copper phthalocyanine trisulphonate that has the ability to selectively adsorb polycyclic compounds. Blue rayon can be used in situ, in columns or in flasks. This method showed to be efficient in the extraction of important classes of environmental contaminants like the polycyclic aromatic hydrocarbons (PAHs, aromatic amines and phenylbenzotriazoles (PBTAs and can be an important tool in monitoring studies for the evaluation of water quality.

  10. Free tyrosine and tyrosine-rich peptide-dependent superoxide generation catalyzed by a copper-binding, threonine-rich neurotoxic peptide derived from prion protein

    Directory of Open Access Journals (Sweden)

    Ken Yokawa, Tomoko Kagenishi, Kaishi Goto, Tomonori Kawano

    2009-01-01

    Full Text Available Previously, generation of superoxide anion (O2•- catalyzed by Cu-binding peptides derived from human prion protein (model sequence for helical Cu-binding motif VNITKQHTVTTTT was most active in the presence of catecholamines and related aromatic monoamines such as phenylethylamine and tyramine, has been reported [Kawano, T., Int J Biol Sci 2007; 3: 57-63]. The peptide sequence (corresponding to helix 2 tested here is known as threonine-rich neurotoxic peptide. In the present article, the redox behaviors of aromatic monoamines, 20 amino acids and prion-derived tyrosine-rich peptide sequences were compared as putative targets of the oxidative reactions mediated with the threonine-rich prion-peptide. For detection of O2•-, an O2•--specific chemiluminescence probe, Cypridina luciferin analog was used. We found that an aromatic amino acid, tyrosine (structurally similar to tyramine behaves as one of the best substrates for the O2•- generating reaction (conversion from hydrogen peroxide catalyzed by Cu-bound prion helical peptide. Data suggested that phenolic moiety is required to be an active substrate while the presence of neither carboxyl group nor amino group was necessarily required. In addition to the action of free tyrosine, effect of two tyrosine-rich peptide sequences YYR and DYEDRYYRENMHR found in human prion corresponding to the tyrosine-rich region was tested as putative substrates for the threonine-rich neurotoxic peptide. YYR motif (found twice in the Y-rich region showed 2- to 3-fold higher activity compared to free tyrosine. Comparison of Y-rich sequence consisted of 13 amino acids and its Y-to-F substitution mutant sequence revealed that the tyrosine-residues on Y-rich peptide derived from prion may contribute to the higher production of O2•-. These data suggest that the tyrosine residues on prion molecules could be additional targets of the prion-mediated reactions through intra- or inter-molecular interactions. Lastly

  11. Free tyrosine and tyrosine-rich peptide-dependent superoxide generation catalyzed by a copper-binding, threonine-rich neurotoxic peptide derived from prion protein.

    Science.gov (United States)

    Yokawa, Ken; Kagenishi, Tomoko; Goto, Kaishi; Kawano, Tomonori

    2009-01-01

    Previously, generation of superoxide anion (O(2)(*-)) catalyzed by Cu-binding peptides derived from human prion protein (model sequence for helical Cu-binding motif VNITKQHTVTTTT was most active) in the presence of catecholamines and related aromatic monoamines such as phenylethylamine and tyramine, has been reported [Kawano, T., Int J Biol Sci 2007; 3: 57-63]. The peptide sequence (corresponding to helix 2) tested here is known as threonine-rich neurotoxic peptide. In the present article, the redox behaviors of aromatic monoamines, 20 amino acids and prion-derived tyrosine-rich peptide sequences were compared as putative targets of the oxidative reactions mediated with the threonine-rich prion-peptide. For detection of O(2)(*-), an O(2)(*-)-specific chemiluminescence probe, Cypridina luciferin analog was used. We found that an aromatic amino acid, tyrosine (structurally similar to tyramine) behaves as one of the best substrates for the O(2)(*-) generating reaction (conversion from hydrogen peroxide) catalyzed by Cu-bound prion helical peptide. Data suggested that phenolic moiety is required to be an active substrate while the presence of neither carboxyl group nor amino group was necessarily required. In addition to the action of free tyrosine, effect of two tyrosine-rich peptide sequences YYR and DYEDRYYRENMHR found in human prion corresponding to the tyrosine-rich region was tested as putative substrates for the threonine-rich neurotoxic peptide. YYR motif (found twice in the Y-rich region) showed 2- to 3-fold higher activity compared to free tyrosine. Comparison of Y-rich sequence consisted of 13 amino acids and its Y-to-F substitution mutant sequence revealed that the tyrosine-residues on Y-rich peptide derived from prion may contribute to the higher production of O(2)(*-). These data suggest that the tyrosine residues on prion molecules could be additional targets of the prion-mediated reactions through intra- or inter-molecular interactions. Lastly, possible

  12. Chinese Copper Manufacturers Expand Overseas

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>In 2012,China’s apparent copper consumption reached 8.84 million tons,accounting for 43%of the global total demand.Spurred by strong demand,China’s copper smelting capacity roars with annual average growth in domestic copper smelting capacity reaching approx-

  13. Simon Labbé’s work on iron and copper homeostasis

    OpenAIRE

    2010-01-01

    Iron and copper have a wealth of functions in biological systems, which makes them essential micronutrients for all living organisms. Defects in iron and copper homeostasis are directly responsible for diseases, and have been linked to impaired development, metabolic syndromes and fungal virulence. Consequently, it is crucial to gain a comprehensive understanding of the molecular bases of iron- and copper-dependent proteins in living systems. Simon Labbé maintains parallel programs on iron an...

  14. Fabrication and Characterization of Metallic Copper and Copper Oxide Nanoflowers

    Directory of Open Access Journals (Sweden)

    *H. S. Virk

    2011-12-01

    Full Text Available Copper nanoflowers have been fabricated using two different techniques; electro-deposition of copper in polymer and anodic alumina templates, and cytyltrimethal ammonium bromide (CTAB-assisted hydrothermal method. Scanning Electron Microscope (SEM images record some interesting morphologies of metallic copper nanoflowers. Field Emission Scanning Electron Microscope (FESEM has been used to determine morphology and composition of copper oxide nanoflowers. X-ray diffraction (XRD pattern reveals the monoclinic phase of CuO in the crystallographic structure of copper oxide nanoflowers. There is an element of random artistic design of nature, rather than science, in exotic patterns of nanoflowers fabricated in our laboratory.

  15. Metallo-pathways to Alzheimer's disease: lessons from genetic disorders of copper trafficking.

    Science.gov (United States)

    Greenough, M A; Ramírez Munoz, A; Bush, A I; Opazo, C M

    2016-09-01

    Copper is an essential metal ion that provides catalytic function to numerous enzymes and also regulates neurotransmission and intracellular signaling. Conversely, a deficiency or excess of copper can cause chronic disease in humans. Menkes and Wilson disease are two rare heritable disorders of copper transport that are characterized by copper deficiency and copper overload, respectively. Changes to copper status are also a common feature of several neurodegenerative disorders including Alzheimer's disease (AD), Parkinson's disease (PD) and Amyotrophic lateral sclerosis (ALS). In the case of AD, which is characterized by brain copper depletion, changes in the distribution of copper has been linked with various aspects of the disease process; protein aggregation, defective protein degradation, oxidative stress, inflammation and mitochondrial dysfunction. Although AD is a multifactorial disease that is likely caused by a breakdown in multiple cellular pathways, copper and other metal ions such as iron and zinc play a central role in many of these cellular processes. Pioneering work by researchers who have studied relatively rare copper transport diseases has shed light on potential metal ion related disease mechanisms in other forms of neurodegeneration such as AD.

  16. Mechanistic studies of copper(II)-mediated oxidation of vic-dioxime to furoxan

    Indian Academy of Sciences (India)

    Oindrila Das; Tapan Kanti Paine

    2012-11-01

    The oxidation of vic-dioximes to furoxans by copper(II) perchlorate in acetonitrile as the oxidant has been discussed. This method was found to be applicable for a broad range of vic-dioximes. Copper complexes of 1,10-phenanthroline derived furoxans were isolated by oxidation of the corresponding copper(II) complexes of 1,10-phenanthroline based dioximes. In exploring the mechanism of copper(II)-mediated oxidative cyclization of vic-dioxime, a transient blue species was observed in the reaction pathway. Based on the spectroscopic signatures and reactivity patterns, the intermediate was proposed to be a dioximatecopper(II)-dinitrosoalkene complex. These results along with the role of metal ion and solvent in the oxidative transformation reaction are discussed in this review.

  17. Copper induces the expression of cholesterogenic genes in human macrophages.

    Science.gov (United States)

    Svensson, Per Arne; Englund, Mikael C O; Markström, Emilia; Ohlsson, Bertil G; Jernås, Margareta; Billig, Håkan; Torgerson, Jarl S; Wiklund, Olov; Carlsson, Lena M S; Carlsson, Björn

    2003-07-01

    Accumulation of lipids and cholesterol by macrophages and subsequent transformation into foam cells are key features in development of atherosclerosis. Serum copper concentrations have been shown to be associated with cardiovascular disease. However, the mechanism behind the proatherogenic effect of copper is not clear. We used DNA microarrays to define the changes in gene expression profile in response to copper exposure of human macrophages. Expression monitoring by DNA microarray revealed 91 genes that were regulated. Copper increased the expression of seven cholesterogenic genes (3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) synthase, IPP isomerase, squalene synthase, squalene epoxidase, methyl sterol oxidase, H105e3 mRNA and sterol-C5-desaturase) and low-density lipoprotein receptor (LDL-R), and decreased the expression of CD36 and lipid binding proteins. The expression of LDL-R and HMG CoA reductase was also investigated using real time PCR. The expression of both of these genes was increased after copper treatment of macrophages (Pmechanism for the association between copper and atherosclerosis. The effect of copper on cholesterogenic genes may also have implications for liver steatosis in early stages of Wilson's disease.

  18. Industrial experiment of copper electrolyte purification by copper arsenite

    Institute of Scientific and Technical Information of China (English)

    ZHENG Ya-jie; XIAO Fa-xin; WANG Yong; LI Chun-hua; XU Wei; JIAN Hong-sheng; MA Yut-ian

    2008-01-01

    Copper electrolyte was purified by copper arsenite that was prepared with As2O3. And electrolysis experiments of purified electrolyte were carried out at 235 and 305 A/m2, respectively. The results show that the yield of copper arsenite is up to 98.64% when the molar ratio of Cu to As is 1.5 in the preparation of copper arsenite. The removal rates of Sb and Bi reach 74.11% and 65.60% respectively after copper arsenite is added in electrolyte. The concentrations of As, Sb and Bi in electrolyte nearly remain constant during electrolysis of 13 d. The appearances of cathode copper obtained at 235 and 305 A/m2 are slippery and even, and the qualification rate is 100% according to the Chinese standard of high-pure cathode copper(GB/T467-97).

  19. Precursors for formation of copper selenide, indium selenide, copper indium diselenide, and/or copper indium gallium diselenide films

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Calvin J; Miedaner, Alexander; Van Hest, Maikel; Ginley, David S

    2014-11-04

    Liquid-based precursors for formation of Copper Selenide, Indium Selenide, Copper Indium Diselenide, and/or copper Indium Galium Diselenide include copper-organoselenides, particulate copper selenide suspensions, copper selenide ethylene diamine in liquid solvent, nanoparticulate indium selenide suspensions, and indium selenide ethylene diamine coordination compounds in solvent. These liquid-based precursors can be deposited in liquid form onto substrates and treated by rapid thermal processing to form crystalline copper selenide and indium selenide films.

  20. Anti-cytomegalovirus activity of the anthraquinone atanyl blue PRL.

    Science.gov (United States)

    Alam, Zohaib; Al-Mahdi, Zainab; Zhu, Yali; McKee, Zachary; Parris, Deborah S; Parikh, Hardik I; Kellogg, Glen E; Kuchta, Alison; McVoy, Michael A

    2015-02-01

    Human cytomegalovirus (CMV) causes significant disease in immunocompromised patients and serious birth defects if acquired in utero. Available CMV antivirals target the viral DNA polymerase, have significant toxicities, and suffer from resistance. New drugs targeting different pathways would be beneficial. The anthraquinone emodin is proposed to inhibit herpes simplex virus by blocking the viral nuclease. Emodin and related anthraquinones are also reported to inhibit CMV. In the present study, emodin reduced CMV infectious yield with an EC50 of 4.9μM but was cytotoxic at concentrations only twofold higher. Related anthraquinones acid blue 40 and alizarin violet R inhibited CMV at only high concentrations (238-265μM) that were also cytotoxic. However, atanyl blue PRL inhibited infectious yield of CMV with an EC50 of 6.3μM, significantly below its 50% cytotoxic concentration of 216μM. Atanyl blue PRL reduced CMV infectivity and inhibited spread. When added up to 1h after infection, it dramatically reduced CMV immediate early protein expression and blocked viral DNA synthesis. However, it had no antiviral activity when added 24h after infection. Interestingly, atanyl blue PRL inhibited nuclease activities of purified CMV UL98 protein with IC50 of 4.5 and 9.3μM. These results indicate that atanyl blue PRL targets very early post-entry events in CMV replication and suggest it may act through inhibition of UL98, making it a novel CMV inhibitor. This compound may provide valuable insights into molecular events that occur at the earliest times post-infection and serve as a lead structure for antiviral development.

  1. Calculation and optimization of the copper (II sulphate monohydrate from copper (II sulphate pentahydrate production process in a fluidized bed dryer

    Directory of Open Access Journals (Sweden)

    Kaluđerović-Radoičić Tatjana

    2015-01-01

    Full Text Available In this paper the process of the copper (II sulphate monohydrate from copper (II sulphate pentahydrate (also known as a Blue vitriol or Bluestone production was analyzed. Copper (II sulphate pentahydrate is one of the most important copper salts which has been known since the ancient Egyptians. In the nineteenth century its application as a fungicide was discovered which provoked wide industrial production. Molecule of the copper (II sulphate pentahydrate is a crystalohydrate with five water molecules linked by chemical bonds to a molecule of the copper (II sulphate. Copper (II sulphate exists as a series of compounds that differ in their degree of hydratation. The anhydrous form is a pale green or gray-white powder, whereas the pentahydrate (CuSO4•5H2O, the most commonly encountered salt, is bright blue. In order to obtain copper (II sulphate monohydrate from copper (II sulphate pentahydrate four water molecules need to be removed. To determine the optimum temperature and time required for the removal of four water molecules from a molecule of pentahydrate in this work thermogravimetric (TGA analysis was performed. Thermogravimetric (TGA analysis - dehydration of copper (II sulphate pentahydrate is done using simultaneous TG-DSC thermal analyzer DTG-Q600 SDT from TA Instruments. Analyzes was carried out for two type of samples, the sample containing particles of the average diameter equal to 0.17 mm and the particles of the average diameter 0.5 mm. In addition, fluidization and drying curve was determined using a semi-industrial fluidization column. On top, the industrial fluidization column aimed to produce 300 tones per month of copper (II sulphate monohydrate was designed. Material and energy calculations were performed using software packages Simprosys 3.0 and SuperPro Designer 5.1. Simprosys 3.0 is a software package designed for the modeling and simulation of a drying process as well as for 20 different unit operations. Super

  2. Copper induces hepatocyte injury due to the endoplasmic reticulum stress in cultured cells and patients with Wilson disease.

    Science.gov (United States)

    Oe, Shinji; Miyagawa, Koichiro; Honma, Yuichi; Harada, Masaru

    2016-09-10

    Copper is an essential trace element, however, excess copper is harmful to human health. Excess copper-derived oxidants contribute to the progression of Wilson disease, and oxidative stress induces accumulation of abnormal proteins. It is known that the endoplasmic reticulum (ER) plays an important role in proper protein folding, and that accumulation of misfolded proteins disturbs ER homeostasis resulting in ER stress. However, copper-induced ER homeostasis disturbance has not been fully clarified. We treated human hepatoma cell line (Huh7) and immortalized-human hepatocyte cell line (OUMS29) with copper and chemical chaperones, including 4-phenylbutyrate and ursodeoxycholic acid. We examined copper-induced oxidative stress, ER stress and apoptosis by immunofluorescence microscopy and immunoblot analyses. Furthermore, we examined the effects of copper on carcinogenesis. Excess copper induced not only oxidative stress but also ER stress. Furthermore, excess copper induced DNA damage and reduced cell proliferation. Chemical chaperones reduced this copper-induced hepatotoxicity. Excess copper induced hepatotoxicity via ER stress. We also confirmed the abnormality of ultra-structure of the ER of hepatocytes in patients with Wilson disease. These findings show that ER stress plays a pivotal role in Wilson disease, and suggests that chemical chaperones may have beneficial effects in the treatment of Wilson disease.

  3. An Investigation of Low Biofouling Copper-charged Membranes

    Science.gov (United States)

    Asapu, Sunitha

    with increased biofouling resistance. The goal of this project was to develop low-biofouling nanofiltration cellulose acetate (CA) membranes through functionalization with metal chelating ligands charged with biocidal metal ions, i.e. copper ions. To this end, glycidyl methacrylate (GMA), an epoxy, was used to attach a chelating agent, iminodiacetic acid (IDA) to facilitate the charging of copper to the membrane surface. Both CA and CA-GMA membranes were cast using the phase-inversion method. The CA-GMA membranes were then charged with copper ions to make them low biofouling. Pore size distribution analysis of CA and copper charged membranes were conducted using various molecular weights of polyethylene glycol (PEG). CA and copper-charged membranes were characterized using Fourier Transform Infrared (FTIR), contact angle to measure hydrophilicity changes, and using scanning electron microscope (SEM) coupled with X-ray energy dispersive spectroscopy EDS to monitor copper leaching. Permeation experiments were conducted with distilled (DI) water, protein solutions, and synthetic brackish water containing microorganisms. The DI water permeation of the copper-charged membranes was initially lower than the CA membranes. The membranes were then subjected to bovine serum albumin (BSA) and lipase filtration. The copper-charged membranes showed higher pure water flux values for both proteins as compared to CA membranes. The rejection of BSA and lipase was the same for both the copper charged and CA membranes. The filtration with the synthetic brackish water showed that copper-charged membranes had higher flux values as compared to CA membranes, and biofouling analysis showed more bacteria on the CA membranes as compared to copper-charged membranes. Therefore, the copper-charged membranes made here have shown a potential to be used as low-biofouling membranes in the future.

  4. Exogenous Nitric Oxide Involved in Subcellular Distribution and Chemical Forms of Cu2+Under Copper Stress in Tomato Seedlings

    Institute of Scientific and Technical Information of China (English)

    DONG Yu-xiu; WANG Xiu-feng; CUI Xiu-min

    2013-01-01

    Nitric oxide (NO), a bioactive signaling molecule, serves as an antioxidant and anti-stress agent under abiotic stress. A hydroponics experiment was conducted to investigate the effects of sodium nitroprusside (SNP), a NO donor, on tomato seedlings exposed to 50 µmol L-1 CuCl2. The results show that copper is primarily stored in the soluble cell sap fraction in the roots, especially after treatment with Cu+SNP treatment, which accounted for 66.2%of the total copper content. The copper concentration gradually decreased from the roots to the leaves. In the leaves, exogenous NO induces the storage of excess copper in the cell walls. Copper stress decreases the proportion of copper integrated with pectates and proteins, but exogenous NO remarkably reverses this trend. The alleviating effect of NO is blocked by hemoglobin. Thus, exogenous NO is likely involved in the regulation of the subcellular copper concentrations and its chemical forms under copper stress. Although exogenous NO inhibited the absorption and transport of excess copper to some extent, the copper accumulation in tomato seedlings signiifcantly increased under copper stress. The use of exogenous NO to enhance copper tolerance in some plants is a promising method for copper remediation.

  5. Creative Copper Crests

    Science.gov (United States)

    Knab, Thomas

    2011-01-01

    In this article, the author discusses how to create an art activity that would link the computer-created business cards of fourth-grade students with an upcoming school-wide medieval event. Creating family crests from copper foil would be a great connection, since they, like business cards, are an individual's way to identify themselves to others.…

  6. Effects of Dietary Protein and Fat Sources on Nutrient Digestibility and Nitrogen Metabolism of Growing Blue Foxes%饲粮蛋白质和脂肪来源对育成前期蓝狐营养物质消化率和氮代谢的影响

    Institute of Scientific and Technical Information of China (English)

    云春凤; 耿业业; 张铁涛; 崔虎; 高秀华; 杨福合; 邢秀梅

    2012-01-01

    This experiment was conducted to evaluate the effects of dietary protein and fat sources on nutrient digestibility and nitrogen metabolism of growing blue foxes. A double-factor design was adopted in this experiment. Two dietary protein sources were plant protein (P plant) and animal protein (P animal) , and two dietary fat sources were soybean oil (F plant) and lard (F animal) , which were used in four kinds of experimental diets (P plant and F plant, P plant and F animal, P animal and F plant and P animal and F animal). A total of 80 (55 ±5)-day-old healthy blue foxes with the similar body weight were randomly assigned to 4 groups with 10 males and 10 females in each group, and foxes in each group were fed 1 kind of experimental diets. The experiment included a preset period for 14 days and a test period for 60 days. The results showed as follows: digestibility of dry matter, crude protein and gross energy in P plant group were significantly higher than those in P animal group (P <0.05 or P <0. 01) , but biological value of protein in P plant group was significantly lower than that in P animal group ( P <0. 01) ; digestibility of fat in F animal group was lower than that in F plant group (P<0.01) , but nitrogen intake, nitrogen retention, net protein utilization and biological value of protein in F animal group were significantly higher than those in F plant group (P<0.05 or P<0.01). In conclusion, for blue foxes, nutrient digestibility of plant protein feed is higher, but biological value of protein is lower than that of animal protein feed. If feeding blue fox with plant protein mainly in practical production, the balance of amina acids should be considered. Fat digestibility of soybean oil is higher, but lard can improve nitrogen metabolism and nitrogen retention. So the effect of production will be better when using mixed fat. [ Chinese Journal of Animal Nutrition, 2012, 24 (9) : 1721 -1730 ]%本试验旨在研究饲粮蛋白质和脂肪来源对育成前

  7. Adsorption of Methylene Blue, Bromophenol Blue, and Coomassie Brilliant Blue by α-chitin nanoparticles

    Directory of Open Access Journals (Sweden)

    Solairaj Dhananasekaran

    2016-01-01

    Full Text Available Expelling of dyestuff into water resource system causes major thread to the environment. Adsorption is the cost effective and potential method to remove the dyes from the effluents. Therefore, an attempt was made to study the adsorption of dyestuff (Methylene Blue (MB, Bromophenol Blue (BPB and Coomassie Brilliant Blue (CBB by α-chitin nanoparticles (CNP prepared from Penaeus monodon (Fabricius, 1798 shell waste. On contrary to the most recognizable adsorption studies using chitin, this is the first study using unique nanoparticles of ⩽50 nm used for the dye adsorption process. The results showed that the adsorption process increased with increase in the concentration of CNP, contact time and temperature with the dyestuff, whereas the adsorption process decreased with increase in the initial dye concentration and strong acidic pH. The results from Fourier transform infrared (FTIR spectroscopy confirmed that the interaction between dyestuff and CNP involved physical adsorption. The adsorption process obeys Langmuir isotherm (R2 values were 0.992, 0.999 and 0.992 for MB, BPB and CBB, and RL value lies between 0 and 1 for all the three dyes and pseudo second order kinetics (R2 values were 0.996, 0.999 and 0.996 for MB, BPB and CBB more effectively. The isotherm and kinetic models confirmed that CNP can be used as a suitable adsorbent material for the removal of dyestuff from effluents.

  8. Microbial peptide de-coppers mitochondria: implications for Wilson disease.

    Science.gov (United States)

    Kaler, Stephen G

    2016-07-01

    The severe liver pathology of untreated Wilson disease (WD) is associated with massive copper overload caused by mutations in a liver-specific copper-transporting ATPase, ATP7B. While early, presymptomatic detection and chelation with conventional copper-binding molecules enables effective and life-saving treatment, liver transplantation is the sole option currently available for those with advanced disease. In this issue of the JCI, Lichtmannegger, Leitzinger, and colleagues delineate the therapeutic effect of methanobactin (MB), a potent bacterial copper-binding protein, at three late stages of disease in a WD rat model. Their results suggest that a formal clinical trial of MB in human subjects with severe hepatic pathology caused by WD would be rational.

  9. Dye removal using modified copper ferrite nanoparticle and RSM analysis.

    Science.gov (United States)

    Mahmoodi, Niyaz Mohammad; Soltani-Gordefaramarzi, Sajjad; Sadeghi-Kiakhani, Moosa

    2013-12-01

    In this paper, copper ferrite nanoparticle (CFN) was synthesized, modified by cetyl trimethylammonium bromide, and characterized. Dye removal ability of the surface modified copper ferrite nanoparticle (SMCFN) from single system was investigated. The physical characteristics of SMCFN were studied using Fourier transform infrared, scanning electron microscopy, and X-ray diffraction. Acid Blue 92, Direct Green 6, Direct Red 23, and Direct Red 80 were used as model compounds. The effect of operational parameters (surfactant concentration, adsorbent dosage, dye concentration, and pH) on dye removal was evaluated. Response surface methodology (RSM) was used for the analysis of the dye removal data. The experimental checking in these optimal conditions confirms good agreements with RSM results. The results showed that the SMCFN being a magnetic adsorbent might be a suitable alternative to remove dyes from colored aqueous solutions.

  10. Chromophore Deprotonation State Alters the Optical Properties of Blue Chromoprotein.

    Directory of Open Access Journals (Sweden)

    Cheng-Yi Chiang

    Full Text Available Chromoproteins (CPs have unique colors and can be used in biological applications. In this work, a novel blue CP with a maximum absorption peak (λmax at 608 nm was identified from the carpet anemone Stichodactyla gigantea (sgBP. In vivo expression of sgBP in zebrafish would change the appearance of the fishes to have a blue color, indicating the potential biomarker function. To enhance the color properties, the crystal structure of sgBP at 2.25 Å resolution was determined to allow structure-based protein engineering. Among the mutations conducted in the Gln-Tyr-Gly chromophore and chromophore environment, a S157C mutation shifted the λmax to 604 nm with an extinction coefficient (ε of 58,029 M-1·cm-1 and darkened the blue color expression. The S157C mutation in the sgBP chromophore environment could affect the color expression by altering the deprotonation state of the phenolic group in the chromophore. Our results provide a structural basis for the blue color enhancement of the biomarker development.

  11. Comparative characteristics of copper, copper chloride, and copper bromide vapor lasers

    Energy Technology Data Exchange (ETDEWEB)

    Kazarian, M.A.; Petrash, G.G.; Trofimov, A.N.

    1980-03-01

    The paper reports the results of a comparative study of copper and copper halide vapor lasers emitting in a repetitively-pulsed regime. Copper chloride and copper bromide vapor lasers are found to have identical lasing characteristics under any excitation conditions. These characteristics are different from those of a copper vapor laser. An average lasing power of 13 W has been obtained for all lasers studied for an efficiency of 1%. It is shown that the choice of a laser will largely depend on the laser design suitability for a specific application.

  12. Fire Whirls, Vortex Breakdown(?), and Blue Whirls

    Science.gov (United States)

    Oran, Elaine; Xiao, Huahua; Gollner, Michael

    2016-11-01

    As we were investigating the efficiency of fire-whirl burning on water, we observed the usual transformation of a pool fire to a fire whirl, and then suddenly, we saw the fire undergo a third transition. A blue cup appeared around the base of the fire whirl, surrounding the yellow flame, the yellow flame receded into the cup and finally disappeared. What remained was a small, rapidly spinning blue flame that burned until the fuel on the water was consumed. The blue whirl was shaped like a spinning cup, closed at the bottom near the water surface, and spreading in radius moving upwards towards the rim. Above the blue cup lip, there was a purple cone-shaped mist. The fuel was usually n-heptane, but at one point it was crude oil, and still the blue whirl formed naturally. The height of the fire whirl on the laboratory pan was larger than a half meter, and this evolved into a blue whirl about 4-8 cm high. Occasionally the blue whirl would become "unstable" and revert to a transitional state of blue cup holding a yellow flame. When the blue whirl formed, turbulence seemed to disappear, and the flame became quiet. We will show videos of how this happened and discuss the evolution of the fire whirl to the blue whirl in vortex-breakdown concepts. This work was supported by and EAGER award from NSF and Minta Martin Endowment Funds in the Department of Aerospace Engineering at the University of Maryland.

  13. The Type 3 copper site is intact but labile in Type 2-depleted laccase

    DEFF Research Database (Denmark)

    Frank, P; Farver, O; Pecht, I

    1983-01-01

    We report results of experiments designed to characterize the Type 1 and Type 3 copper sites in Rhus laccase depleted of Type 2 copper (T2D). Use of the Lowry method for determining protein concentration yielded the value 5620 +/- 570 M-1 cm-1 for the extinction of the 615-nm absorption band...

  14. Insights into copper effect on Proteus hauseri through proteomic and metabolic analyses.

    Science.gov (United States)

    Ng, I-Son; Ye, Chiming; Li, Yuzhe; Chen, Bor-Yann

    2016-02-01

    This is the first-attempt to use liquid chromatography coupled with tandem mass (LC-MS-MS) in deciphering the effects of copper ion on Proteus hauseri. Total 941 proteins in copper-addition (+Cu) group and 898 proteins in non-copper-addition (-Cu) group were found, which containing 221 and 178 differential proteins in +Cu and -Cu group, respectively. Differential proteins in both groups were defined into 14 groups by their functional classification which transport/membrane function proteins were the major different part between the two groups, which took 19.5% and 7.7%, respectively. The result of BioCyc and KEGG analyses on metabolic pathway indicated that copper could interrupted the pathway of chemotaxis CheY and inhibited the swarming of P. hauseri, which provided a potential in controlling the pathogenicity of this strain.

  15. Various Shades of Blue's Functions

    CERN Document Server

    Janik, R A; Papp, G; Zahed, I; Janik, Romuald A.; Nowak, Maciej A.; Papp, Gabor; Zahed, Ismail

    1997-01-01

    We discuss random matrix models in terms of elementary operations on Blue's functions (functional inverse of Green's functions). We show that such operations embody the essence of a number of physical phenomena whether at/or away from the critical points. We illustrate these assertions by borrowing on a number of recent results in effective QCD in vacuum and matter. We provide simple physical arguments in favor of the universality of the continuum QCD spectral oscillations, whether at zero virtuality, in the bulk of the spectrum or at the chiral critical points. We also discuss effective quantum systems of disorder with strong or weak dissipation (Hatano-Nelson localization).

  16. Application of INEPT 109Ag and 15N NMR spectroscopy for the study of metal-ligand interaction of silver analogues of Copper(I) model compounds

    NARCIS (Netherlands)

    Koten, G. van; Stein, G.C. van; Brevard, C.

    1983-01-01

    Because of the presence of copper (in its reduced state) at active sites in protein it has become very important to study copper(I) model complexes by spectroscopic techniques.We now report that if copper(I) in model complexes can be substituted by silver(I) with retention of the structural features

  17. The Menkes and Wilson disease genes counteract in copper toxicosis in Labrador retrievers: a new canine model for copper-metabolism disorders.

    Science.gov (United States)

    Fieten, Hille; Gill, Yadvinder; Martin, Alan J; Concilli, Mafalda; Dirksen, Karen; van Steenbeek, Frank G; Spee, Bart; van den Ingh, Ted S G A M; Martens, Ellen C C P; Festa, Paola; Chesi, Giancarlo; van de Sluis, Bart; Houwen, Roderick H J H; Watson, Adrian L; Aulchenko, Yurii S; Hodgkinson, Victoria L; Zhu, Sha; Petris, Michael J; Polishchuk, Roman S; Leegwater, Peter A J; Rothuizen, Jan

    2016-01-01

    The deleterious effects of a disrupted copper metabolism are illustrated by hereditary diseases caused by mutations in the genes coding for the copper transporters ATP7A and ATP7B. Menkes disease, involving ATP7A, is a fatal neurodegenerative disorder of copper deficiency. Mutations in ATP7B lead to Wilson disease, which is characterized by a predominantly hepatic copper accumulation. The low incidence and the phenotypic variability of human copper toxicosis hamper identification of causal genes or modifier genes involved in the disease pathogenesis. The Labrador retriever was recently characterized as a new canine model for copper toxicosis. Purebred dogs have reduced genetic variability, which facilitates identification of genes involved in complex heritable traits that might influence phenotype in both humans and dogs. We performed a genome-wide association study in 235 Labrador retrievers and identified two chromosome regions containing ATP7A and ATP7B that were associated with variation in hepatic copper levels. DNA sequence analysis identified missense mutations in each gene. The amino acid substitution ATP7B:p.Arg1453Gln was associated with copper accumulation, whereas the amino acid substitution ATP7A:p.Thr327Ile partly protected against copper accumulation. Confocal microscopy indicated that aberrant copper metabolism upon expression of the ATP7B variant occurred because of mis-localization of the protein in the endoplasmic reticulum. Dermal fibroblasts derived from ATP7A:p.Thr327Ile dogs showed copper accumulation and delayed excretion. We identified the Labrador retriever as the first natural, non-rodent model for ATP7B-associated copper toxicosis. Attenuation of copper accumulation by the ATP7A mutation sheds an interesting light on the interplay of copper transporters in body copper homeostasis and warrants a thorough investigation of ATP7A as a modifier gene in copper-metabolism disorders. The identification of two new functional variants in ATP7A and

  18. Production of ultrahigh purity copper using waste copper nitrate solution.

    Science.gov (United States)

    Choi, J Y; Kim, D S

    2003-04-25

    The production of ultrahigh purity copper (99.9999%) by electrolysis in the presence of a cementation barrier has been attempted employing a waste nitric copper etching solution as the electrolyte. The amount of copper deposited on the cathode increased almost linearly with electrolysis time and the purity of copper was observed to increase as the electrolyte concentration was increased. At some point, however, as the electrolyte concentration increased, the purity of copper decreased slightly. As the total surface area of cementation barrier increased, the purity of product increased. The electrolyte temperature should be maintained below 35 degrees C in the range of investigated electrolysis conditions to obtain the ultrahigh purity copper. Considering that several industrial waste solutions contain valuable metallic components the result of present study may support a claim that electrowinning is a very desirable process for their treatment and recovery.

  19. Tongling:Copper Industry Giant Takes Shape

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>Centering on the strategic goal of building "World Copper Capital", Tongling constantly extends its product lines and improves the copper industry chain. Now, the copper industry with a production value of RMB 100 billion has taken shape.As the largest copper wire rod manufacturer in Asia, Tongling Quanwei Copper Technologies Co., Ltd., upon its moving into the local market,

  20. Copper Ion as a New Leakage Tracer

    Directory of Open Access Journals (Sweden)

    Modaresi J.

    2013-12-01

    Full Text Available Statement of Problem: Most failures of root canal treatments are caused by bacteria. Studies showed that the most common cause of endodontic failures were the incomplete obturation of the root canal and the lack of adequate apical seal. Some in-vitro methods are used to estimate sealing quality, generally by measuring microleakage that allows the tracer agent to penetrate the filled canal.Purpose: Conventional methods of evaluating the seal of endodontically treated teeth are complicated and have some drawbacks. We used copper ion diffusion method to assess the leakage and the results were compared to dye penetration method.Materials and Method: The crowns of 21 extracted teeth were cut off at the CEJ level. After preparing the canals, the teeth were placed in tubes containing saline. They were divided randomly into 15 experimental cases; 3 positive and 3 negative controls. Positive controls were filled by single cone without sealer while the experimental and the negative control groups were filled by lateral technique. The coronal portion of gutta was removed and 9mm was left. The external surface of each tooth was coated with nail polish. Two millimeters of apical portion was immersed into 9ml of distilled water and 0.3ml of CuSO4 solution was injected into the coronal portion. After 2 days, copper sulfate was measured by an atomic absorption spectrophotometer. The teeth were then immersed in 2% methylene blue for 24 hours, sectioned and the extent of dye penetration was measured by a stereomicroscope.Results: The maximum and minimum recorded copper ion concentrations for the experimental group were 18.37 and 2.87ppm respectively. The maximum and minimum recorded dye penetrations for the experimental group were 8.5 and 3.5mm respectively. The statistical analysis, adopting paired samples test, showed poor correlation between average recorded results of two methods.Conclusion: Based on our results, there was no significant correlation between

  1. ATOX1 gene silencing increases susceptibility to anticancer therapy based on copper ionophores or chelating drugs.

    Science.gov (United States)

    Barresi, Vincenza; Spampinato, Giorgia; Musso, Nicolò; Trovato Salinaro, Angela; Rizzarelli, Enrico; Condorelli, Daniele Filippo

    2016-03-01

    Copper is a catalytic cofactor required for the normal function of many enzymes involved in fundamental biological processes but highly cytotoxic when in excess. Therefore its homeostasis and distribution is strictly regulated by a network of transporters and intracellular chaperones. ATOX1 (antioxidant protein 1) is a copper chaperone that plays a role in copper homeostasis by binding and transporting cytosolic copper to ATPase proteins in the trans-Golgi network. In the present study the Caco-2 cell line, a colon carcinoma cell line, was used as an in vitro model to evaluate if ATOX1 deficiency could affect sensitivity to experimentally induced copper dyshomeostasis. Silencing of ATOX1 increased toxicity of a short treatment with a high concentration of Cu(2+). Copper ionophores, such as 5-chloro-8-hydroxyquinoline, induced a copper-dependent cell toxicity which was significantly potentiated after ATOX1 silencing. The copper chelator TPEN (N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine) produced a form of cell toxicity that was reversed by the addition of Cu(2+). ATOX1 silencing increased Caco-2 cell sensitivity to TPEN toxicity. Our results suggest the possibility of a therapy with copper-chelating or ionophore drugs in subtypes of tumors showing specific alterations in ATOX1 expression.

  2. Geothermal Technologies Program Blue Ribbon Panel Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-06-17

    The Geothermal Technologies Program assembled a geothermal Blue Ribbon Panel on March 22-23, 2011 in Albuquerque, New Mexico for a guided discussion on the future of geothermal energy in the United States and the role of the DOE Program. The Geothermal Blue Ribbon Panel Report captures the discussions and recommendations of the experts. An addendum is available here: http://www.eere.energy.gov/geothermal/pdfs/gtp_blue_ribbon_panel_report_addendum10-2011.pdf

  3. Modulation of copper deficiency responses by diurnal and circadian rhythms in Arabidopsis thaliana.

    Science.gov (United States)

    Perea-García, Ana; Andrés-Bordería, Amparo; Mayo de Andrés, Sonia; Sanz, Amparo; Davis, Amanda M; Davis, Seth J; Huijser, Peter; Peñarrubia, Lola

    2016-01-01

    Copper homeostasis under deficiency is regulated by the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE7 (SPL7) transcription factor. The daily oscillating expression of two SPL7-dependent copper deficiency markers, COPPER TRANSPORTER (COPT2) and IRON SUPEROXIDE DISMUTASE (FSD1), has been followed by quantitative PCR and in promoter:LUCIFERASE transgenic plants. Both genes showed circadian and diurnal regulation. Under copper deficiency, their expression decreased drastically in continuous darkness. Accordingly, total copper content was slightly reduced in etiolated seedlings under copper deficiency. The expression of SPL7 and its targets COPT2 and FSD1 was differently regulated in various light signalling mutants. On the other hand, increased copper levels reduced the amplitude of nuclear circadian clock components, such as GIGANTEA (GI). The alteration of copper homeostasis in the COPT1 overexpression line and spl7 mutants also modified the amplitude of a classical clock output, namely the circadian oscillation of cotyledon movements. In the spl7 mutant, the period of the oscillation remained constant. These results suggest a feedback of copper transport on the circadian clock and the integration of rhythmic copper homeostasis into the central oscillator of plants.

  4. Overlap of copper and iron uptake systems in mitochondria in Saccharomyces cerevisiae.

    Science.gov (United States)

    Vest, Katherine E; Wang, Jing; Gammon, Micah G; Maynard, Margaret K; White, Olivia L; Cobine, Jai A; Mahone, Wilkerson K; Cobine, Paul A

    2016-01-01

    In Saccharomyces cerevisiae, the mitochondrial carrier family protein Pic2 imports copper into the matrix. Deletion of PIC2 causes defects in mitochondrial copper uptake and copper-dependent growth phenotypes owing to decreased cytochrome c oxidase activity. However, copper import is not completely eliminated in this mutant, so alternative transport systems must exist. Deletion of MRS3, a component of the iron import machinery, also causes a copper-dependent growth defect on non-fermentable carbon. Deletion of both PIC2 and MRS3 led to a more severe respiratory growth defect than either individual mutant. In addition, MRS3 expressed from a high copy number vector was able to suppress the oxygen consumption and copper uptake defects of a strain lacking PIC2. When expressed in Lactococcus lactis, Mrs3 mediated copper and iron import. Finally, a PIC2 and MRS3 double mutant prevented the copper-dependent activation of a heterologously expressed copper sensor in the mitochondrial intermembrane space. Taken together, these data support a role for the iron transporter Mrs3 in copper import into the mitochondrial matrix.

  5. The fictile coordination chemistry of cuprous-thiolate sites in copper chaperones.

    Science.gov (United States)

    Pushie, M Jake; Zhang, Limei; Pickering, Ingrid J; George, Graham N

    2012-06-01

    Copper plays vital roles in the active sites of cytochrome oxidase and in several other enzymes essential for human health. Copper is also highly toxic when dysregulated; because of this an elaborate array of accessory proteins have evolved which act as intracellular carriers or chaperones for the copper ions. In most cases chaperones transport cuprous copper. This review discusses some of the chemistry of these copper sites, with a view to some of the structural factors in copper coordination which are important in the biological function of these chaperones. The coordination chemistry and accessible geometries of the cuprous oxidation state are remarkably plastic and we discuss how this may relate to biological function. This article is part of a Special Issue entitled: Biogenesis/Assembly of Respiratory Enzyme Complexes.

  6. What has fluorescent sensing told us about copper and brain malfunction?

    Science.gov (United States)

    Shen, Clara; New, Elizabeth J

    2015-01-01

    There is growing evidence that copper and copper-binding proteins are common denominators in the mechanisms of neurodegenerative diseases such as Alzheimer's and Parkinson's. These pathologies have been linked to changes in copper homeostasis, but the question of whether this is a causal or effective relationship remains unanswered. A clearer understanding will require a way to visualise copper at a molecular level in vivo. Fluorescent metal sensing is one such tool, and a number of Cu(i) probes have been reported with excellent sensing properties and complementary studies that validate their biological application. This review critically evaluates the recent progress in fluorescent copper sensing and suggests some new directions for future study of copper neurochemistry.

  7. Copper transporters and chaperones: Their function on angiogenesis and cellular signalling

    Indian Academy of Sciences (India)

    SR BHARATHI DEVI; DHIVYA M ALOYSIUS; KN SULOCHANA

    2016-09-01

    Copper, although known as a micronutrient, has a pivotal role in modulating the cellular metabolism. Many studieshave reported the role of copper in angiogenesis. Copper chaperones are intracellular proteins that mediate coppertrafficking to various cell organelles. However, the role and function of copper chaperones in relation to angiogenesishas to be further explored. The intracellular copper levels when in excess are deleterious and certain mutations ofcopper chaperones have been shown to induce cell death and influence various cellular metabolisms. The study ofthese chaperones will be helpful in understanding the players in the cascade of events in angiogenesis and their role incellular metabolic pathways. In this review we have briefly listed the copper chaperones associated with angiogenicand metabolic signalling and their function.

  8. Copper pathology in vulnerable brain regions in Parkinson's disease. : Copper pathology in PD

    OpenAIRE

    Davies, Katherine,; Bohic, Sylvain; Carmona, Asunción; Ortega, Richard; Cottam, Veronica; Hare, Dominic; Finberg, John,; Reyes, Stefanie; Halliday, Glenda; Mercer, Julian; Double, Kay,

    2014-01-01

    International audience; Synchrotron-based x-ray fluorescence microscopy, immunofluorescence, and Western blotting were used to investigate changes in copper (Cu) and Cu-associated pathways in the vulnerable substantia nigra (SN) and locus coeruleus (LC) and in nondegenerating brain regions in cases of Parkinson's disease (PD) and appropriate healthy and disease controls. In PD and incidental Lewy body disease, levels of Cu and Cu transporter protein 1, were significantly reduced in surviving ...

  9. Systems Biology Approach in Chlamydomonas Reveals Connections between Copper Nutrition and Multiple Metabolic Steps[C][W][OA

    Science.gov (United States)

    Castruita, Madeli; Casero, David; Karpowicz, Steven J.; Kropat, Janette; Vieler, Astrid; Hsieh, Scott I.; Yan, Weihong; Cokus, Shawn; Loo, Joseph A.; Benning, Christoph; Pellegrini, Matteo; Merchant, Sabeeha S.

    2011-01-01

    In this work, we query the Chlamydomonas reinhardtii copper regulon at a whole-genome level. Our RNA-Seq data simulation and analysis pipeline validated a 2-fold cutoff and 10 RPKM (reads per kilobase of mappable length per million mapped reads) (~1 mRNA per cell) to reveal 63 CRR1 targets plus another 86 copper-responsive genes. Proteomic and immunoblot analyses captured 25% of the corresponding proteins, whose abundance was also dependent on copper nutrition, validating transcriptional regulation as a major control mechanism for copper signaling in Chlamydomonas. The impact of copper deficiency on the expression of several O2-dependent enzymes included steps in lipid modification pathways. Quantitative lipid profiles indicated increased polyunsaturation of fatty acids on thylakoid membrane digalactosyldiglycerides, indicating a global impact of copper deficiency on the photosynthetic apparatus. Discovery of a putative plastid copper chaperone and a membrane protease in the thylakoid suggest a mechanism for blocking copper utilization in the chloroplast. We also found an example of copper sparing in the N assimilation pathway: the replacement of copper amine oxidase by a flavin-dependent backup enzyme. Forty percent of the targets are previously uncharacterized proteins, indicating considerable potential for new discovery in the biology of copper. PMID:21498682

  10. Copper stress induces a global stress response in Staphylococcus aureus and represses sae and agr expression and biofilm formation.

    Science.gov (United States)

    Baker, Jonathan; Sitthisak, Sutthirat; Sengupta, Mrittika; Johnson, Miranda; Jayaswal, R K; Morrissey, Julie A

    2010-01-01

    Copper is an important cofactor for many enzymes; however, high levels of copper are toxic. Therefore, bacteria must ensure there is sufficient copper for use as a cofactor but, more importantly, must limit free intracellular levels to prevent toxicity. In this study, we have used DNA microarray to identify Staphylococcus aureus copper-responsive genes. Transcriptional profiling of S. aureus SH1000 grown in excess copper identified a number of genes which fall into four groups, suggesting that S. aureus has four main mechanisms for adapting to high levels of environmental copper, as follows: (i) induction of direct copper homeostasis mechanisms; (ii) increased oxidative stress resistance; (iii) expression of the misfolded protein response; and (iv) repression of a number of transporters and global regulators such as Agr and Sae. Our experimental data confirm that resistance to oxidative stress and particularly to H2O2 scavenging is an important S. aureus copper resistance mechanism. Our previous studies have demonstrated that Eap and Emp proteins, which are positively regulated by Agr and Sae, are required for biofilm formation under low-iron growth conditions. Our transcriptional analysis has confirmed that sae, agr, and eap are repressed under high-copper conditions and that biofilm formation is indeed repressed under high-copper conditions. Therefore, our results may provide an explanation for how copper films can prevent biofilm formation on catheters.

  11. Copper binding regulates intracellular alpha-synuclein localisation, aggregation and toxicity.

    Science.gov (United States)

    Wang, Xiaoyan; Moualla, Dima; Wright, Josephine A; Brown, David R

    2010-05-01

    Alpha-synuclein is a natively unfolded protein that aggregates and forms inclusions that are associated with a range of diseases that include Parkinson's Disease and Dementia with Lewy Bodies. The mechanism behind the formation of these inclusions and their possible role in disease remains unclear. Alpha-synuclein has also been shown to bind metals including copper and iron. We used a cell culture model of alpha-synuclein aggregation to examine the relationship between metals and formation of aggregates of the protein. While the levels of iron appear to have no role in aggregate formation or localisation of the protein in cells, copper appears to be important for both aggregation and cellular localisation of alpha-synuclein. Reduction in cellular copper resulted in a great decrease in aggregate formation both in terms of large aggregates visible in cells and oligomers observed in western blot analysis of cell extracts. Reduction in copper also resulted in a change in localisation of the protein which became more intensely localised to the plasma membrane in medium with low copper. These changes were reversed when copper was restored to the cells. Mutants of the copper binding domains altered the response to copper. Deletion of either the N- or C-termini resulted in a loss of aggregation while deletion of the C-termini also resulted in a loss of membrane association. Increased expression of alpha-synuclein also increased cell sensitivity to the toxicity of copper. These results suggest that the potential pathological role of alpha-synuclein aggregates is dependent upon the copper binding capacity of the protein.

  12. Direct Production of Copper

    Science.gov (United States)

    Victorovich, G. S.; Bell, M. C.; Diaz, C. M.; Bell, J. A. E.

    1987-09-01

    The use of commercially pure oxygen in flash smelting a typical chalcopyrite concentrate or a low grade comminuted matte directly to copper produces a large excess of heat. The heat balance is controlled by adjusting the calorific value of the solid feed. A portion of the sulfide material is roasted to produce a calcine which is blended with unroasted material, and the blend is then autogeneously smelted with oxygen and flux directly to copper. Either iron silicate or iron calcareous slags are produced, both being subject to a slag cleaning treatment. Practically all of the sulfur is contained in a continuous stream of SO2 gas, most of which is strong enough for liquefaction. A particularly attractive feature of these technologies is that no radically new metallurgical equipment needs to be developed. The oxygen smelting can be carried out not only in the Inco type flash furnace but in other suitable smelters such as cyclone furnaces. Another major advantage stems from abolishion of the ever-troublesome converter aisle, which is replaced with continuous roasting of a fraction of the copper sulfide feed.

  13. Engineering of blood vessel patterns by angio-morphogens [angiotropins]: non-mitogenic copper-ribonucleoprotein cytokins [CuRNP ribokines] with their metalloregulated constituents of RAGE-binding S100-EF-hand proteins and extracellular RNA bioaptamers in vascular remodeling of tissue and angiogenesis in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Wissler, J.H. [ARCONS Applied Research, Bad Nauheim (Germany)

    2001-12-01

    Tissue vascularization is requisite to successful cell-based therapies, biomaterial design and implant integration. Thus, known problems in ossointegration of avascular implants in connection with the generation of bone tissue reflect arrays of general problems of socio-economic relevance existing in reparative medicine still waiting for to be solved. For this purpose, morphogenesis and remodeling of endothelial angio-architectures in tissue and in vitro by isolated non-mitogenic angio-morphogens [angiotropins] are considered in terms of their structure, function and action mechanisms. Extracellular angiotropins are secreted by activated leukocytes/monocytes/macrophages. They are a family of cytokines with morphogen bioactivity selectively directed to endothelial cells. Their structure was deciphered as metalloregulated copper-ribonucleoproteins [CuRNP ribokines]. They are built up of angiotropin-related S100-EF-hand protein [ARP] and highly modified and edited 5'end-phosphorylated RNA [ARNA], complexed together by copper ions. Oxidant-sensitive ARNA and their precursors represent novel types in a RNA world: They are the first isolated and sequenced forms of extracellular RNA [eRNA], may act as cytokine and bioaptamer, contain isoguanosine [crotonoside] as modified nucleoside and show up copper as RNA-structuring transition metal ion. By metalloregulated bioaptamer functions, ARNA impart novel biofunctions to RAGE-binding S100-EF-hand proteins. Angiotropin morphogens were shown suitable for neointiation and remodeling of blood vessel patterns in different, adult, embryonal and artificial tissues. These neovascular patterns manifest regulated hemodynamics for preventing tissue necrosis, supporting tissue functions and promoting wound healing. As evaluated in skin and muscle vascularization, the neovascular patterns are integrated into homeostatic control mechanisms of tissue. Thus, the morphogens show up beneficial perspectives and are suggested useful tools

  14. Isolation, Identification and Bioinformatics Analysis of CAT Protein Related with Hepatotoxity by Copper Nanoparticles in Rats%纳米铜对大鼠肝脏毒性相关蛋白过氧化氢酶的分离鉴定及生物信息学分析

    Institute of Scientific and Technical Information of China (English)

    董书伟; 高昭辉; 申小云; 薛慧文; 荔霞

    2012-01-01

    [目的]分离和鉴定纳米铜对大鼠肝脏毒性相关蛋白过氧化氢酶(catalase,CAT),探讨CAT在毒性发挥中的作用,为揭示纳米铜对肝脏毒性机制提供依据.[方法]应用2-DE技术和PDQuest 8.0软件在大鼠肝脏蛋白组中筛选纳米铜对肝脏毒性差异蛋白,经质谱鉴定后进行生物信息学分析.[结果]筛选到下调的差异蛋白点6602和7702与肝毒性相关,鉴定均为CAT蛋白;其性质稳定,有一定亲水性,无信号肽,定位于细胞质,可能属于非分泌性蛋白,含有过氧化氢酶活性位点64FDRERIPERVVHAKGAG80和过氧化氢酶亚铁血红素配合基位点354RLFAYPDTH362等功能位点;无规则卷曲、α螺旋和延伸链是其主要的二级结构元件,并预测了其三级结构图;同源性分析表明,大鼠的CAT与其它8个物种有较高同源性,并构建了CAT蛋白的系统进化树.[结论]纳米铜通过下调大鼠肝脏中CAT蛋白表达,引起肝细胞氧化应激损伤,可能是其发挥毒性作用的途径之一.%[Objective] In order to investigate the hepatotoxic mechanisms of nanoparticles copper, catalase (CAT) was isolated and identified from liver, and analyzed by bioinformatics, which is related with hepatotoxity induced by copper nanoparticles in rats. [Method] The differential expression proteins related with hepatotoxity of copper nanoparticles were screened by 2-DE and PDQuest 8.0 software and then analyzed by bioinformatics after identified by MALDI-TOF-TOF MS through comparative proteomics strategy. [Result] The 6602 and 7702 spots of differentially expressed proteins were found to associate with hepatotoxity. They were identified as CAT protein which was located in the cytoplasm. This hydrophilic protein had no signal peptide, and was non-secreted protein. It also contained catalase active sites 64FDRERIPERWHAKGAG80 and catalase heme ligand sites 354RLFAYPDTH362. The random coils, o-helices and extended chains were its main secondary structural

  15. Understanding the antimicrobial activity behind thin- and thick-rolled copper plates.

    Science.gov (United States)

    Yousuf, Basit; Ahire, Jayesh J; Dicks, Leon M T

    2016-06-01

    The aim of this study was to compare the antibacterial properties of the surfaces of copper plates that were rolled to a thickness of 25 and 100 μm. Differences in topology of 25- and 100-μm-thick copper plates were studied using scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). Antibacterial activity of the copper surfaces was tested against strains of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Listeria monocytogenes, Salmonella typhimurium, Streptococcus sp. BY1, Enterococcus sp. BY2, and Bacillus cereus BY3. Changes in viable cell numbers were determined by plating onto optimal growth media and staining with LIVE/DEAD BacLight™. Changes in metabolic activity were recorded by expression of the luciferase (lux) gene. Cell morphology was studied using SEM. Accumulation and diffusion of copper from cells were recorded using inductively coupled plasma mass spectroscopy (ICP-MS). Lipid and protein oxidation were recorded spectrophotometrically. Surfaces of 25-μm-thick copper plates were rough compared to that of 100-μm-thick copper plates. For most species, a five-log reduction in cell numbers, cell membrane instability, and a decline in metabolic activity were recorded after 15 min of exposure to 25-μm-thick copper plates. Copper accumulated in the cells, and lipids and proteins were oxidized. The rough surface of thinner copper plates (25 μm thick) released more copper and was more antimicrobial compared to thicker (100 μm) copper plates. Cell death was attributed to destabilization of the cell membrane, lipid peroxidation, and protein oxidation.

  16. Oxidation Mechanism of Copper Selenide

    Science.gov (United States)

    Taskinen, Pekka; Patana, Sonja; Kobylin, Petri; Latostenmaa, Petri

    2014-09-01

    The oxidation mechanism of copper selenide was investigated at deselenization temperatures of copper refining anode slimes. The isothermal roasting of synthetic, massive copper selenide in flowing oxygen and oxygen - 20% sulfur dioxide mixtures at 450-550 °C indicate that in both atmospheres the mass of Cu2Se increases as a function of time, due to formation of copper selenite as an intermediate product. Copper selenide oxidises to copper oxides without formation of thick copper selenite scales, and a significant fraction of selenium is vaporized as SeO2(g). The oxidation product scales on Cu2Se are porous which allows transport of atmospheric oxygen to the reaction zone and selenium dioxide vapor to the surrounding gas. Predominance area diagrams of the copper-selenium system, constructed for selenium roasting conditions, indicate that the stable phase of copper in a selenium roaster gas with SO2 is the sulfate CuSO4. The cuprous oxide formed in decomposition of Cu2Se is further sulfated to CuSO4.

  17. Copper and copper-nickel-alloys - An overview

    Energy Technology Data Exchange (ETDEWEB)

    Klassert, Anton; Tikana, Ladji [Deutsches Kupferinstitut e.V. Am Bonneshof 5, 40474 Duesseldorf (Germany)

    2004-07-01

    With the increasing level of industrialization the demand for and the number of copper alloys rose in an uninterrupted way. Today, the copper alloys take an important position amongst metallic materials due to the large variety of their technological properties and applications. Nowadays there exist over 3.000 standardized alloys. Copper takes the third place of all metals with a worldwide consumption of over 15 millions tons per year, following only to steel and aluminum. In a modern industrial society we meet copper in all ranges of the life (electro-technology, building and construction industry, mechanical engineering, automotive, chemistry, offshore, marine engineering, medical applications and others.). Copper is the first metal customized by humanity. Its name is attributed to the island Cyprus, which supplied in the antiquity copper to Greece, Rome and the other Mediterranean countries. The Romans called it 'ore from Cyprus' (aes cyprium), later cuprum. Copper deposited occasionally also dapper and could be processed in the recent stone age simply by hammering. Already in early historical time copper alloys with 20 to 50 percent tin was used for the production of mirrors because of their high reflecting power. Although the elementary nickel is an element discovered only recently from a historical perspective, its application in alloys - without any knowledge of the alloy composition - occurred at least throughout the last 2.000 years. The oldest copper-nickel coin originates from the time around 235 B.C.. Only around 1800 AD nickel was isolated as a metallic element. In particular in the sea and offshore technology copper nickel alloys found a broad field of applications in piping systems and for valves and armatures. The excellent combination of characteristics like corrosion resistance, erosion stability and bio-fouling resistance with excellent mechanical strength are at the basis of this success. An experience of many decades supports the use

  18. Mechanochemical reactions on copper-based compounds

    NARCIS (Netherlands)

    Castricum, H.L.; Bakker, H.; Poels, E.K.

    1999-01-01

    Mechanochemical reactions of copper and copper oxides with oxygen and carbon dioxide are discussed, as well as decomposition and reduction of copper compounds by mechanical milling under high-vacuum conditions.

  19. Carnitine supplementation modulates high dietary copper-induced oxidative toxicity and reduced performance in laying hens.

    Science.gov (United States)

    Güçlü, Berrin Kocaoğlu; Kara, Kanber; Çakır, Latife; Çetin, Ebru; Kanbur, Murat

    2011-12-01

    This experiment was conducted to evaluate the effects of L-carnitine on performance, egg quality and certain biochemical parameters in laying hens fed a diet containing high levels of copper proteinate. Forty-eight 42-week-old laying hens were divided into four groups with four replicates. The laying hens were fed with a basal diet (control) or the basal diet supplemented with either 400 mg carnitine (Car)/kg diet, 800 mg copper proteinate (CuP)/kg diet or 400 mg carnitine + 800 mg copper (Car+CuP)/kg diet, for 6 weeks. Supplemental CuP decreased feed consumption (p supplemental CuP and Car+CuP. Supplemental CuP caused an increase in plasma malondialdehyde (p carnitine and copper combination may prevent the possible adverse effects of high dietary copper on performance and lipid peroxidation in hens.

  20. Anticancer activity of Ficus religiosa engineered copper oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sankar, Renu; Maheswari, Ramasamy; Karthik, Selvaraju [Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620 024, Tamilnadu (India); Shivashangari, Kanchi Subramanian, E-mail: shivashangari@gmail.com [Regional Forensic Science Laboratory, Tiruchirapalli, Tamilnadu (India); Ravikumar, Vilwanathan, E-mail: ravikumarbdu@gmail.com [Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620 024, Tamilnadu (India)

    2014-11-01

    The design, synthesis, characterization and application of biologically synthesized nanomaterials have become a vital branch of nanotechnology. There is a budding need to develop a method for environmentally benign metal nanoparticle synthesis, that do not use toxic chemicals in the synthesis protocols to avoid adverse effects in medical applications. Here, it is a report on an eco-friendly process for rapid synthesis of copper oxide nanoparticles using Ficus religiosa leaf extract as reducing and protecting agent. The synthesized copper oxide nanoparticles were confirmed by UV–vis spectrophotometer, absorbance peaks at 285 nm. The copper oxide nanoparticles were analyzed with field emission-scanning electron microscope (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS) and X-ray diffraction (XRD) spectrum. The FE-SEM and DLS analyses exposed that copper oxide nanoparticles are spherical in shape with an average particle size of 577 nm. FT-IR spectral analysis elucidates the occurrence of biomolecules required for the reduction of copper oxide ions. Zeta potential studies showed that the surface charge of the formed nanoparticles was highly negative. The XRD pattern revealed that synthesized nanoparticles are crystalline in nature. Further, biological activities of the synthesized nanoparticles were confirmed based on its stable anti-cancer effects. The apoptotic effect of copper oxide nanoparticles is mediated by the generation of reactive oxygen species (ROS) involving the disruption of mitochondrial membrane potential (Δψm) in A549 cells. The observed characteristics and results obtained in our in vitro assays suggest that the copper nanoparticles might be a potential anticancer agent. - Highlights: • Biogenic synthesis of copper oxide nanoparticles by leaf extract of Ficus religiosa • Characterized via UV–vis, FT-IR, DLS, FE-SEM with EDAX and XRD • Protein may act as an encapsulating, reducing and stabilizing

  1. Effects of Dietary Protein Level on Growth Performance, Nutrient Digestion and Metabolism, and Serum Biochemical Indices of Blue Foxes during the Winter Hair Period%饲粮蛋白质水平对冬毛期蓝狐生长性能、营养物质消化代谢及血清生化指标的影响

    Institute of Scientific and Technical Information of China (English)

    崔虎; 张铁涛; 张志强; 耿业业; 高秀华; 杨福合; 邢秀梅

    2011-01-01

    本试验旨在研究饲粮蛋白质水平对冬毛期蓝狐生长性能、营养物质消化代谢及血清生化指标的影响.选取16周龄、平均体重为(5.71±0.60) kg的健康雄性蓝狐90只,随机分为6组,每组15个重复,每个重复1只.各组蓝狐分别饲喂蛋白质水平为24%(Ⅰ组)、26%(Ⅱ组)、28%(Ⅲ组)、30%(Ⅳ组)、32%(Ⅴ组)、34%(Ⅵ组)的试验饲粮.预试期7d,正试期80 d.结果表明,Ⅲ组蓝狐的末重、平均日增重和饲料转化率均为最高,其中末重极显著高于Ⅰ、Ⅱ、Ⅴ和Ⅵ组(P<0.01),平均日增重和饲料转化率显著或极显著高于Ⅰ、Ⅴ和Ⅵ组(P<0.05或P<0.01).Ⅱ、Ⅲ和Ⅳ组的干物质消化率极显著高于Ⅰ、Ⅴ和Ⅵ组(P<0.01).蛋白质消化率随着饲粮蛋白质水平的升高有先升高后降低的趋势,但组间差异不显著(P>0.05);而脂肪消化率在饲粮蛋白质水平为28%时最高,且与其他各组存在显著差异(P<0.05).随着饲粮蛋白质水平的升高,粪氮和尿氮排出量都有升高的趋势,且Ⅴ和Ⅵ组的尿氮排出量极显著高于Ⅰ、Ⅱ、Ⅲ和Ⅳ组(P<0.01).饲粮蛋白质水平在28%时,蓝狐的净蛋白质利用率和蛋白质生物学价值均为最高,同时氮沉积也处在较高水平.随着饲粮蛋白质水平的升高,血清尿素氮含量呈升高的趋势,而血清总蛋白和白蛋白含量则先升高后降低,且均以Ⅲ组最高.各组间血清谷丙转氨酶活性没有显著差异(P>0.05),而血清谷草转氨酶活性Ⅰ组显著低于其他各组(P<0.05).结合平均日增重、营养物质消化率、氮代谢以及血清生化指标得出,冬毛期蓝狐饲粮适宜的蛋白质水平为28%.%The experiment was conducted to study the effects of dietary protein level on growth performance, nutrient digestion and metabolism, and serum biochemical indices of blue foxes during the winter hair period. Ninety healthy male blue foxes with an average body weight of

  2. Ecology of Blue Straggler Stars

    CERN Document Server

    Boffin, H M J; Beccari, G

    2014-01-01

    The existence of blue straggler stars (BSS), which appear younger, hotter, and more massive than their siblings, is at odds with a simple picture of stellar evolution, as such stars should have exhausted their nuclear fuel and evolved long ago to become cooling white dwarfs. As such, BSS could just be some quirks but in fact their understanding requires a deep knowledge of many different areas in astronomy, from stellar evolution through cluster dynamics, from chemical abundances to stellar populations. In November 2012, a workshop on this important topic took place at the ESO Chilean headquarters in Santiago. The many topics covered at this workshop were introduced by very comprehensive invited reviews, providing a unique and insightful view on the field. These reviews have now become chapters of the first ever book on BSS.

  3. Liquid biofuels from blue biomass

    DEFF Research Database (Denmark)

    Kádár, Zsófia; Jensen, Annette Eva; Bangsø Nielsen, Henrik

    2011-01-01

    medium, light as energy source and they capture CO2 for the synthesis of new organic material, thus can grow on non-agricultural land, without increasing food prices, or using fresh water. Due to all these advantages in addition to very high biomass yield with high carbohydrate content, macroalgaes can......Marine (blue) biomasses, such as macroalgaes, represent a huge unexploited amount of biomass. With their various chemical compositions, macroalgaes can be a potential substrate for food, feed, biomaterials, pharmaceuticals, health care products and also for bioenergy. Algae use seawater as a growth...... be the well suited candidates as feedstock for biofuel production in the future. The aim of our studies is to examine the possibility producing liquid biofuel (ethanol and butanol) from macroalgaes....

  4. Laccase-mediated Remazol Brilliant Blue R decolorization in a fixed-bed bioreactor.

    Science.gov (United States)

    Palmieri, Gianna; Giardina, Paola; Sannia, Giovanni

    2005-01-01

    A crude laccase mixture preparation from Pleurotus ostreatus cultures supplemented with copper and ferulic acid was used to decolorize the anthraquinonic dye Remazol Brilliant Blue R (RBBR). Performance of this enzymatic system was tested, and a maximum of 70% decolorization was achievable under optimal conditions. The crude preparation was immobilized by entrapment in copper alginate beads attaining 65% yield of laccase activity. Stability of the immobilized laccases was remarkably increased in comparison with that of the free enzyme preparation. Efficiency of the immobilized system was evaluated during stepwise dye additions in batch operations. Under the best conditions, 70% RBBR decolorization was achieved even after 20 cycles, although decolorization time exponentially increased after the 10th cycle. Different fixed-bed bioreactors were prepared and analyzed in continuous decolorization processes. The best performance was obtained by decreasing the amount of enzyme loaded and by improving laccase retention using chitosan-coated alginate beads.

  5. A targetable fluorescent sensor reveals that copper-deficient SCO1 and SCO2 patient cells prioritize mitochondrial copper homeostasis.

    Science.gov (United States)

    Dodani, Sheel C; Leary, Scot C; Cobine, Paul A; Winge, Dennis R; Chang, Christopher J

    2011-06-08

    We present the design, synthesis, spectroscopy, and biological applications of Mitochondrial Coppersensor-1 (Mito-CS1), a new type of targetable fluorescent sensor for imaging exchangeable mitochondrial copper pools in living cells. Mito-CS1 is a bifunctional reporter that combines a Cu(+)-responsive fluorescent platform with a mitochondrial-targeting triphenylphosphonium moiety for localizing the probe to this organelle. Molecular imaging with Mito-CS1 establishes that this new chemical tool can detect changes in labile mitochondrial Cu(+) in a model HEK 293T cell line as well as in human fibroblasts. Moreover, we utilized Mito-CS1 in a combined imaging and biochemical study in fibroblasts derived from patients with mutations in the two synthesis of cytochrome c oxidase 1 and 2 proteins (SCO1 and SCO2), each of which is required for assembly and metalation of functionally active cytochrome c oxidase (COX). Interestingly, we observe that although defects in these mitochondrial metallochaperones lead to a global copper deficiency at the whole cell level, total copper and exchangeable mitochondrial Cu(+) pools in SCO1 and SCO2 patient fibroblasts are largely unaltered relative to wild-type controls. Our findings reveal that the cell maintains copper homeostasis in mitochondria even in situations of copper deficiency and mitochondrial metallochaperone malfunction, illustrating the importance of regulating copper stores in this energy-producing organelle.

  6. Removal of copper from ferrous scrap

    Science.gov (United States)

    Blander, Milton; Sinha, Shome N.

    1990-01-01

    A process for removing copper from ferrous or other metal scrap in which the scrap is contacted with a polyvalent metal sulfide slag in the presence of an excess of copper-sulfide forming additive to convert the copper to copper sulfide which is extracted into the slag to provide a ratio of copper in the slag to copper in the metal scrap of at least about 10.

  7. Apparent Digestibility of Dry Matter and Crude Protein of 11 Kinds of Fresh Ingredients in Blue Foxes%蓝狐对11种鲜饲料原料中干物质和粗蛋白质表观消化率的研究

    Institute of Scientific and Technical Information of China (English)

    孙伟丽; 李光玉; 刘凤华; 鲍坤; 钟伟; 常忠娟; 刘佰阳

    2011-01-01

    To measure the apparent digestibility of dry matter (DM) and crude protein (CP) of different in gredients for blue foxes, one hundred and twenty healthy male blue foxes in replacement period with similar body weight and age, were selected and randomly divided into 12 groups of 10 each. The ingredients with bet ter palatability (trash fish, chicken carcasses, egg, beef, and chicken) were measured the digestibility of DM and CP in blue foxes by the method of feeding directly, while the ingredients with common palatability (bitter ling, silver carp, chicken giblets, chicken liver, cow liver and yellow croaker) were measured by a difference method. The results showed that; 1) The apparent digestibility of DM in ingredients measured by the method of feeding directly had a significant difference (P 0.05), and the apparent digestibility of DM in trash fish, chicken carcasses, egg in the shell, beef and chicken were 84.39% , 87.24% , 61.14% , 94.64% and 88.12% , respectively; the ap parent digestibility of CP in those feedstuffs were 94.60% , 91.19% , 91.24% , 97.25% and 96. 69% , re spectively. 2) The apparent digestibility of DM and CP in ingredients measured by the difference method had a significant difference (P <0. 05), and the apparent digestibility of DM in bitterling, silver carp, chicken gib lets, cow liver, chicken liver and yellow croaker were 70.39% , 59.82% , 71.63% , 70. 56% , 79.17% and 75. 27% , respectively; the apparent digestibility of CP in those feedstuffs were 83. 06% , 77.28% , 89.88% , 68. 26% , 75. 58% , 69.13% and 94.60% , respectively. In conclusion, blue foxes have good digestive abili ty to the experimental ingredients, and the trash fish, chicken carcasses, egg, beef, chicken, bitterling and chicken giblets are of high quality protein ingredients for blue foxes. Moreover, for silver carp, chicken liver, cow liver and yellow croaker, their proper supplemental proportions in diets of blue foxes depend on their palat ability , nutrients

  8. The effect of blue light exposure in an ocular melanoma animal model

    Directory of Open Access Journals (Sweden)

    Odashiro Alexandre N

    2009-04-01

    Full Text Available Abstract Background Uveal melanoma (UM cell lines, when exposed to blue light in vitro, show a significant increase in proliferation. In order to determine if similar effects could be seen in vivo, we investigated the effect of blue light exposure in a xenograft animal model of UM. Methods Twenty New Zealand albino rabbits were injected with 1.0 × 106 human UM cells (92.1 in the suprachoroidal space of the right eye. Animals were equally divided into two groups; the experimental group was exposed to blue light, while the control group was protected from blue light exposure. The eyes were enucleated after sacrifice and the proliferation rates of the re-cultured tumor cells were assessed using a Sulforhodamine-B assay. Cells were re-cultured for 1 passage only in order to maintain any in vivo cellular changes. Furthermore, Proliferating Cell Nuclear Antigen (PCNA protein expression was used to ascertain differences in cellular proliferation between both groups in formalin-fixed, paraffin-embedded eyes (FFPE. Results Blue light exposure led to a statistically significant increase in proliferation for cell lines derived from intraocular tumors (p Conclusion There is an increasing amount of data suggesting that blue light exposure may influence the progression of UM. Our results support this notion and warrant further studies to evaluate the ability of blue light filtering lenses to slow disease progression in UM patients.

  9. Anion channels and the stimulation of anthocyanin accumulation by blue light in Arabidopsis seedlings

    Science.gov (United States)

    Noh, B.; Spalding, E. P.; Evans, M. H. (Principal Investigator)

    1998-01-01

    Activation of anion channels by blue light begins within seconds of irradiation in seedlings and is related to the ensuing growth inhibition. 5-Nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) is a potent, selective, and reversible blocker of these anion channels in Arabidopsis thaliana. Here we show that 20 microM NPPB blocked 72% of the blue-light-induced accumulation of anthocyanin pigments in seedlings. Feeding biosynthetic intermediates to wild-type and tt5 seedlings provided evidence that NPPB prevented blue light from up-regulating one or more steps between and including phenylalanine ammonia lyase and chalcone isomerase. NPPB was found to have no significant effect on the blue-light-induced increase in transcript levels of PAL1, CHS, CHI, or DFR, which are genes that encode anthocyanin-biosynthetic enzymes. Immunoblots revealed that NPPB also did not inhibit the accumulation of the chalcone synthase, chalcone isomerase, or flavanone-3-hydroxylase proteins. This is in contrast to the reduced anthocyanin accumulation displayed by a mutant lacking the HY4 blue-light receptor, as hy4 displayed reduced expression of the above enzymes. Taken together, the data indicate that blue light acting through HY4 leads to an increase in the amount of biosynthetic enzymes but blue light must also act through a separate, anion-channel-dependent system to create a fully functional biosynthetic pathway.

  10. Blue Skies, Coffee Creamer, and Rayleigh Scattering

    Science.gov (United States)

    Liebl, Michael

    2010-01-01

    The first physical explanation of Earths blue sky was fashioned in 1871 by Lord Rayleigh. Many discussions of Rayleigh scattering and approaches to studying it both in and out of the classroom are available. Rayleigh scattering accounts for the blue color of the sky and the orange/red color of the Sun near sunset and sunrise, and a number of…

  11. Adenosine triphosphate-dependent copper transport in human liver

    NARCIS (Netherlands)

    vandenBerg, GJ; Wolters, H; Veld, GI; Slooff, MJH; Heymans, GSA; Kuipers, F; Vonk, RJ

    1996-01-01

    Background/Aim: The recent cloning and sequencing of the Wilson disease gene indicates that hepatic copper (Cu) transport is mediated by a P-type ATPase. The location of this Cu-transporting protein within the hepatocyte is not known; in view of its proposed function and current concepts of hepatic

  12. Nickel, copper and cobalt coalescence in copper cliff converter slag

    Directory of Open Access Journals (Sweden)

    Wolf A.

    2016-01-01

    Full Text Available The aim of this investigation is to assess the effect of various additives on coalescence of nickel, copper and cobalt from slags generated during nickel extraction. The analyzed fluxes were silica and lime while examined reductants were pig iron, ferrosilicon and copper-silicon compound. Slag was settled at the different holding temperatures for various times in conditions that simulated the industrial environment. The newly formed matte and slag were characterized by their chemical composition and morphology. Silica flux generated higher partition coefficients for nickel and copper than the addition of lime. Additives used as reducing agents had higher valuable metal recovery rates and corresponding partition coefficients than fluxes. Microstructural studies showed that slag formed after adding reductants consisted of primarily fayalite, with some minute traces of magnetite as the secondary phase. Addition of 5 wt% of pig iron, ferrosilicon and copper-silicon alloys favored the formation of a metallized matte which increased Cu, Ni and Co recoveries. Addition of copper-silicon alloys with low silicon content was efficient in copper recovery but coalescence of the other metals was low. Slag treated with the ferrosilicon facilitated the highest cobalt recovery while copper-silicon alloys with silicon content above 10 wt% resulted in high coalescence of nickel and copper, 87 % and 72 % respectively.

  13. Study of Copper Substitute in High Copper Price Market Environment

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>The high price of copper drives up industry cost,also it is difficult for terminal products to raise price to transfer the cost pressure brought by increase in copper price,as a result downstream consumption markets instead try to seek

  14. Copper on activated carbon for catalytic wet air oxidation

    Directory of Open Access Journals (Sweden)

    Nora Dolores Martínez

    2009-03-01

    Full Text Available Textile industry is an important source of water contamination. Some of the organic contaminants cannot be eliminated by nature in a reasonable period. Heterogeneous catalytic wet air oxidation is one of the most effective methods to purify wastewater with organic contaminants. In this work, catalysts based on copper supported on activated carbon were synthesized. The activated carbons were obtained from industrial wastes (apricot core and grape stalk of San Juan, Argentina. These were impregnated with a copper salt and thermically treated in an inert atmosphere. Analysis of specific surface, pore volume, p zc, acidity, basicity and XRD patterns were made in order to characterize the catalysts. The catalytic activity was tested in the oxidation of methylene blue (MB and polyvinyl alcohol (PVA in aqueous phase with pure oxygen. Reaction tests were carried out in a Parr batch reactor at different temperatures, with a 0.2 MPa partial pressure of oxygen. The amount of unconverted organics was measured by spectrophotometry. Higher temperatures were necessary for the degradation of PVA compared to those for methylene blue.

  15. Fixation Property of Copper Triazole Wood Preservatives

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    According to AWPA E11-2006 standard,copper fixation rates of several copper-based formulations,such as ammoniacal copper,amine copper,and ammoniacal-ethanolamine copper,as well as alkaline copper quaternary(ACQ),were tested and compared in this paper.And the fixation rates of tebuconazole(TEB) and propiconazole(PPZ) in several formulations,such as copper azole,emulsified type and solvent type,were also compared.The determination of copper content in the leachate was analyzed by atomic absorption spectrom...

  16. An air-stable copper reagent for nucleophilic trifluoromethylthiolation of aryl halides

    KAUST Repository

    Weng, Zhiqiang

    2012-12-12

    A series of copper(I) trifluoromethyl thiolate complexes have been synthesized from the reaction of CuF2 with Me3SiCF 3 and S8 (see scheme; Cu red, F green, N blue, S yellow). These air-stable complexes serve as reagents for the efficient conversion of a wide range of aryl halides into the corresponding aryl trifluoromethyl thioethers in excellent yields. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Reduction of molybdate to molybdenum blue by Klebsiella sp. strain hkeem.

    Science.gov (United States)

    Lim, H K; Syed, M A; Shukor, M Y

    2012-06-01

    A novel molybdate-reducing bacterium, tentatively identified as Klebsiella sp. strain hkeem and based on partial 16s rDNA gene sequencing and phylogenetic analysis, has been isolated. Strain hkeem produced 3 times more molybdenum blue than Serratia sp. strain Dr.Y8; the most potent Mo-reducing bacterium isolated to date. Molybdate was optimally reduced to molybdenum blue using 4.5 mM phosphate, 80 mM molybdate and using 1% (w/v) fructose as a carbon source. Molybdate reduction was optimum at 30 °C and at pH 7.3. The molybdenum blue produced from cellular reduction exhibited absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Inhibitors of electron transport system such as antimycin A, rotenone, sodium azide, and potassium cyanide did not inhibit the molybdenum-reducing enzyme. Mercury, silver, and copper at 1 ppm inhibited molybdenum blue formation in whole cells of strain hkeem.

  18. Triboelectric Nanogenerators for Blue Energy Harvesting.

    Science.gov (United States)

    Khan, Usman; Kim, Sang-Woo

    2016-07-26

    Blue energy in the form of ocean waves offers an enormous energy resource. However, it has yet to be fully exploited in order to make it available for the use of mankind. Blue energy harvesting is a challenging task as the kinetic energy from ocean waves is irregular in amplitude and is at low frequencies. Though electromagnetic generators (EMGs) are well-known for harvesting mechanical kinetic energies, they have a crucial limitation for blue energy conversion. Indeed, the output voltage of EMGs can be impractically low at the low frequencies of ocean waves. In contrast, triboelectric nanogenerators (TENGs) are highly suitable for blue energy harvesting as they can effectively harvest mechanical energies from low frequencies (blue energy harvesting. In this Perspective, we describe some of the recent progress and also address concerns related to durable packaging of TENGs in consideration of harsh marine environments and power management for an efficient power transfer and distribution for commercial applications.

  19. Synthesis of copper/copper oxide nanoparticles by solution plasma

    Science.gov (United States)

    Saito, Genki; Hosokai, Sou; Tsubota, Masakatsu; Akiyama, Tomohiro

    2011-07-01

    This paper describes the synthesis of copper/copper oxide nanoparticles via a solution plasma, in which the effect of the electrolyte and electrolysis time on the morphology of the products was mainly examined. In the experiments, a copper wire as a cathode was immersed in an electrolysis solution of a K2CO3 with the concentration from 0.001 to 0.50 M or a citrate buffer (pH = 4.8), and was melted by the local-concentration of current. The results demonstrated that by using the K2CO3 solution, we obtained CuO nanoflowers with many sharp nanorods, the size of which decreased with decreasing the concentration of the solution. Spherical particles of copper with/without pores formed when the citrate buffer was used. The pores in the copper nanoparticles appeared when the applied voltage changed from 105 V to 130 V, due to the dissolution of Cu2O.

  20. Electroleaching of Copper Waste with Recovery of Copper by Electrodialysis

    Directory of Open Access Journals (Sweden)

    Nuñez P.

    2013-04-01

    Full Text Available A new process to leach and recover copper from solid waste using electric fields was designed. The leaching with electro migration is presented as an alternative to traditional leaching. Preliminary data indicate that the copper ion migration is facilitated by using the electrical potential difference; therefore applying a potential difference in the processes of leaching facilitates the removal of copper. This is especially useful when mineral concentrations are very low. Different phenomena associated with transport of copper in solution are studied to generate a model able predict the state of the copper ion concentration in time. A kinetic model for the process was developed and fitted very well the experimental data.

  1. Determination of Trace Copper (Ⅱ) in Water Samples by Kinetic-spectrophotometry

    Institute of Scientific and Technical Information of China (English)

    QI Yanxia; JI Hongwei; XIN Huizhen; LIU Li

    2007-01-01

    A new kinetic-spectrophotometric method is proposed for the determination of copper ( Ⅱ ). The method is based on the catalytic effect of copper ( Ⅱ ) on the oxidation of weak acid brilliant blue dye (RAWL) by hydrogen peroxide. The copper ( Ⅱ ) can be determined spectrophotometrically by measuring the decrease of absorbance of RAWL at λ = 626 nm using the fix-time method. The optimum reaction conditions are as follows: pH 7.20, buffer solution NaOH-KH2PO4, RAWL (200 mgL-1) 5.00 mL, H2O2 (30%) 0.50 mL, reaction temperature 80 ℃ and reaction time 20 min. The linear range of this method is between 0 μg L-1 and 12 μg L-1 and the limit of detection is 0.011 μg L-1, the relative standard deviation (RSD) in five replicate determinations for 2 and 8 μg L-1 copper ( Ⅱ ) are 3.2% and 2.3%, respectively. Twenty ions do not interfere in the determination of copper ( Ⅱ ). The method has been applied satisfactorily to the determination of copper ( Ⅱ ) in freshwater samples (tap water and Yellow River water from Lijin, Shandong, China) and seawater samples (from the South China Sea), the recovery rates are 98.0%, 102.5% and 96.0%, respectively.

  2. Nanocrystalline copper based microcomposites

    OpenAIRE

    J.P. Stobrawa; Z.M. Rdzawski; W. Głuchowski; J. Domagała-Dubiel

    2012-01-01

    Purpose: The aim of this work was to investigate microstructure, mechanical properties and deformation behavior of copper microcomposites: Cu- Y2O3, Cu- ZrO2 and Cu-WC produced by powder metallurgy techniques.Design/methodology/approach: Tests were made with Cu-Y2O3, Cu-ZrO2 and Cu-WC microcomposites containing up to 2% of a strengthening phase. The materials were fabricated by powder metallurgy techniques, including milling of powders, followed by their compacting and sintering. The main mec...

  3. The Bauschinger Effect in Copper

    DEFF Research Database (Denmark)

    Pedersen, Ole Bøcker; Brown, L .M.; Stobbs, W. M.

    1981-01-01

    A study of the Bauschinger effect in pure copper shows that by comparison with dispersion hardened copper the effect is very small and independent of temperature. This suggests that the obstacles to flow are deformable. A simple composite model based on this principle accounts for the data semi...

  4. Copper and Zinc Metallation Status of Copper Zinc Superoxide Dismutase form Amyotrophic Lateral Sclerosis Transgenic Mice

    Energy Technology Data Exchange (ETDEWEB)

    Lelie, H.L.; Miller, L.; Liba, A.; Bourassa, M.W.; Chattopadhyay, M.; Chan, P.K.; Gralla, E.B.; Borchelt, D.R.; et al

    2010-09-24

    Mutations in the metalloenzyme copper-zinc superoxide dismutase (SOD1) cause one form of familial amyotrophic lateral sclerosis (ALS), and metals are suspected to play a pivotal role in ALS pathology. To learn more about metals in ALS, we determined the metallation states of human wild-type or mutant (G37R, G93A, and H46R/H48Q) SOD1 proteins from SOD1-ALS transgenic mice spinal cords. SOD1 was gently extracted from spinal cord and separated into insoluble (aggregated) and soluble (supernatant) fractions, and then metallation states were determined by HPLC inductively coupled plasma MS. Insoluble SOD1-rich fractions were not enriched in copper and zinc. However, the soluble mutant and WT SOD1s were highly metallated except for the metal-binding-region mutant H46R/H48Q, which did not bind any copper. Due to the stability conferred by high metallation of G37R and G93A, it is unlikely that these soluble SOD1s are prone to aggregation in vivo, supporting the hypothesis that immature nascent SOD1 is the substrate for aggregation. We also investigated the effect of SOD1 overexpression and disease on metal homeostasis in spinal cord cross-sections of SOD1-ALS mice using synchrotron-based x-ray fluorescence microscopy. In each mouse genotype, except for the H46R/H48Q mouse, we found a redistribution of copper between gray and white matters correlated to areas of high SOD1. Interestingly, a disease-specific increase of zinc was observed in the white matter for all mutant SOD1 mice. Together these data provide a picture of copper and zinc in the cell as well as highlight the importance of these metals in understanding SOD1-ALS pathology.

  5. Effects of copper(II) and copper oxides on THMs formation in copper pipe.

    Science.gov (United States)

    Li, Bo; Qu, Jiuhui; Liu, Huijuan; Hu, Chengzhi

    2007-08-01

    Little is known about how the growth of trihalomethanes (THMs) in drinking water is affected in copper pipe. The formation of THMs and chlorine consumption in copper pipe under stagnant flow conditions were investigated. Experiments for the same water held in glass bottles were performed for comparison. Results showed that although THMs levels firstly increased in the presence of chlorine in copper pipe, faster decay of chlorine as compared to the glass bottle affected the rate of THMs formation. The analysis of water phase was supplemented by surface analysis of corrosion scales using X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDX). The results showed the scales on the pipe surface mainly consisted of Cu(2)O, CuO and Cu(OH)(2) or CuCO(3). Designed experiments confirmed that the fast depletion of chlorine in copper pipe was mainly due to effect of Cu(2)O, CuO in corrosion scales on copper pipe. Although copper(II) and copper oxides showed effect on THMs formation, the rapid consumption of chlorine due to copper oxide made THM levels lower than that in glass bottles after 4h. The transformations of CF, DCBM and CDBM to BF were accelerated in the presence of copper(II), cupric oxide and cuprous oxide. The effect of pH on THMs formation was influenced by effect of pH on corrosion of copper pipe. When pH was below 7, THMs levels in copper pipe was higher as compared to glass bottle, but lower when pH was above 7.

  6. Detention of copper by sulfur nanoparticles inhibits the proliferation of A375 malignant melanoma and MCF-7 breast cancer cells.

    Science.gov (United States)

    Liu, Hao; Zhang, Yikai; Zheng, Shanyuan; Weng, Zeping; Ma, Jun; Li, Yangqiu; Xie, Xinyuan; Zheng, Wenjie

    2016-09-01

    Selective induction of cell death or growth inhibition of cancer cells is the future of chemotherapy. Clinical trials have found that cancer tissues are enriched with copper. Based on this finding, many copper-containing compounds and complexes have been designed to "copper" cancer cells using copper as bait. However, recent studies have demonstrated that copper boosts tumor development, and copper deprivation from serum was shown to effectively inhibit the promotion of cancer. Mechanistically, copper is an essential cofactor for mitogen-activated protein kinase (MAPK)/extracellular activating kinase (ERK) kinase (MEK), a central molecule in the BRAF/MEK/ERK pathway. Therefore, depleting copper from cancer cells by directly sequestering copper has a wider field for research and potential for combination therapy. Based on the affinity between sulfur and copper, we therefore designed sulfur nanoparticles (Nano-S) that detain copper, achieving tumor growth restriction. We found that spherical Nano-S could effectively bind copper and form a tighter surficial structure. Moreover, this Nano-S detention of copper effectively inhibited the proliferation of A375 melanoma and MCF-7 breast cancer cells with minimum toxicity to normal cells. Mechanistic studies revealed that Nano-S triggered inactivation of the MEK-ERK pathway followed by inhibition of the proliferation of the A375 and MCF-7 cells. In addition, lower Nano-S concentrations and shorter exposure stimulated the expression of a copper transporter as compensation, which further increased the cellular uptake and anticancer activities of cisplatin. Collectively, our results highlight the potential of Nano-S as an anticancer agent or adjuvant through its detention of copper.

  7. Combining -Omics to Unravel the Impact of Copper Nutrition on Alfalfa (Medicago sativa) Stem Metabolism.

    Science.gov (United States)

    Printz, Bruno; Guerriero, Gea; Sergeant, Kjell; Audinot, Jean-Nicolas; Guignard, Cédric; Renaut, Jenny; Lutts, Stanley; Hausman, Jean-Francois

    2016-02-01

    Copper can be found in the environment at concentrations ranging from a shortage up to the threshold of toxicity for plants, with optimal growth conditions situated in between. The plant stem plays a central role in transferring and distributing minerals, water and other solutes throughout the plant. In this study, alfalfa is exposed to different levels of copper availability, from deficiency to slight excess, and the impact on the metabolism of the stem is assessed by a non-targeted proteomics study and by the expression analysis of key genes controlling plant stem development. Under copper deficiency, the plant stem accumulates specific copper chaperones, the expression of genes involved in stem development is decreased and the concentrations of zinc and molybdenum are increased in comparison with the optimum copper level. At the optimal copper level, the expression of cell wall-related genes increases and proteins playing a role in cell wall deposition and in methionine metabolism accumulate, whereas copper excess imposes a reduction in the concentration of iron in the stem and a reduced abundance of ferritins. Secondary ion mass spectrometry (SIMS) analysis suggests a role for the apoplasm as a copper storage site in the case of copper toxicity.

  8. Chemical Structure of TiO2 Nanotube Photocatalysts Promoted by Copper and Iron

    Directory of Open Access Journals (Sweden)

    Chang-Yu Liao

    2013-01-01

    Full Text Available TiO2 nanotubes (TNTs promoted by copper (5% (Cu-TNT and iron (5% (Fe-TNT were prepared for visible-light photocatalysis. By X-ray absorption near edge structure (XANES spectroscopy, it is found that the enhanced photocatalytic degradation of methylene blue (MB on Cu-TNT and Fe-TNT is associated with the predominant surface photoactive sites A2 ((Ti=OO4. By extended X-ray absorption fine structure (EXAFS spectroscopy, the dispersed copper and iron also cause increases in the Ti–O and Ti–(O–Ti bond distances by 0.01-0.02 and 0.04-0.05 Å, respectively. The decreased Ti–O bonding energy may lead to an increase of photoexcited electron transport. The copper- or-iron promoted TNT can thus enhance photocatalytic degradation of MB under the visible-light radiation.

  9. A novel spectrophotometric determination of copper(Ⅱ) with bromosulphonazo Ⅲ

    Institute of Scientific and Technical Information of China (English)

    Li Yuan; Shu Hui Huo; Xiao Na Ren; Hui Chen

    2008-01-01

    A novel ehromogenic reaction involving copper(Ⅱ) and bromosulphonazo Ⅲ (Br-SAZⅢ) in hexamethylenetetramine-hydrochloric buffer solution was investigated. The results showed that a blue complex of copper(Ⅱ) and bromosulphonazo Ⅲwas formed with a molar ratio of 1:1. The apparent molar absorptivity was 3.3 × 105Lmol-1cm-1 and themaximum absorption peak was at 616.8 nm. The proposed procedure was used for quantitative estimation of Cu(Ⅱ) inthe concentration range of 0-1.024 μg/mL with the detection limit (3σ) of 7.03 × 10-4 μg/mL (n = 20). The relativestandard deviations (RSDs) were 0.56-4,68%. Under the optimized conditions, total copper in the vegetables and tea wassuccessfully determined.

  10. Can greening of aquaculture sequester blue carbon?

    Science.gov (United States)

    Ahmed, Nesar; Bunting, Stuart W; Glaser, Marion; Flaherty, Mark S; Diana, James S

    2016-11-15

    Globally, blue carbon (i.e., carbon in coastal and marine ecosystems) emissions have been seriously augmented due to the devastating effects of anthropogenic pressures on coastal ecosystems including mangrove swamps, salt marshes, and seagrass meadows. The greening of aquaculture, however, including an ecosystem approach to Integrated Aquaculture-Agriculture (IAA) and Integrated Multi-Trophic Aquaculture (IMTA) could play a significant role in reversing this trend, enhancing coastal ecosystems, and sequestering blue carbon. Ponds within IAA farming systems sequester more carbon per unit area than conventional fish ponds, natural lakes, and inland seas. The translocation of shrimp culture from mangrove swamps to offshore IMTA could reduce mangrove loss, reverse blue carbon emissions, and in turn increase storage of blue carbon through restoration of mangroves. Moreover, offshore IMTA may create a barrier to trawl fishing which in turn could help restore seagrasses and further enhance blue carbon sequestration. Seaweed and shellfish culture within IMTA could also help to sequester more blue carbon. The greening of aquaculture could face several challenges that need to be addressed in order to realize substantial benefits from enhanced blue carbon sequestration and eventually contribute to global climate change mitigation.

  11. Nitrogen substituent polarity influences dithiocarbamate-mediated lipid oxidation, nerve copper accumulation, and myelin injury.

    Science.gov (United States)

    Valentine, Holly L; Viquez, Olga M; Amarnath, Kalyani; Amarnath, Venkataraman; Zyskowski, Justin; Kassa, Endalkachew N; Valentine, William M

    2009-01-01

    Dithiocarbamates have a wide spectrum of applications in industry, agriculture, and medicine, with new applications being investigated. Past studies have suggested that the neurotoxicity of some dithiocarbamates may result from copper accumulation, protein oxidative damage, and lipid oxidation. The polarity of a dithiocarbamate's nitrogen substituents influences the lipophilicity of the copper complexes that it generates and thus potentially determines its ability to promote copper accumulation within nerve and induce myelin injury. In the current study, a series of dithiocarbamate-copper complexes differing in their lipophilicity were evaluated for their relative abilities to promote lipid peroxidation determined by malondialdehyde levels generated in an ethyl arachidonate oil-in-water emulsion. In a second component of this study, rats were exposed to either N,N-diethyldithiocarbamate or sarcosine dithiocarbamate; both generated dithiocarbamate-copper complexes that were lipid- and water-soluble, respectively. Following the exposures, brain, tibial nerve, spinal cord, and liver tissue copper levels were measured by inductively coupled mass spectroscopy to assess the relative abilities of these two dithiocarbamates to promote copper accumulation. Peripheral nerve injury was evaluated using grip strengths, nerve conduction velocities, and morphologic changes at the light microscope level. Additionally, the protein expression levels of glutathione transferase alpha and heme-oxygenase-1 in nerve were determined, and the quantity of protein carbonyls was measured to assess levels of oxidative stress and injury. The data provided evidence that dithiocarbamate-copper complexes are redox active and that the ability of dithiocarbamate complexes to promote lipid peroxidation is correlated to the lipophilicity of the complex. Consistent with neurotoxicity requiring the formation of a lipid-soluble copper complex, significant increases in copper accumulation, oxidative

  12. Blue outliers among intermediate redshift quasars

    CERN Document Server

    Marziani, P; Stirpe, G M; Dultzin, D; Del Olmo, A; Martínez-Carballo, M A

    2015-01-01

    [Oiii]{\\lambda}{\\lambda}4959,5007 "blue outliers" -- that are suggestive of outflows in the narrow line region of quasars -- appear to be much more common at intermediate z (high luminosity) than at low z. About 40% of quasars in a Hamburg ESO intermediate-z sample of 52 sources qualify as blue outliers (i.e., quasars with [OIII] {\\lambda}{\\lambda}4959,5007 lines showing large systematic blueshifts with respect to rest frame). We discuss major findings on what has become an intriguing field in active galactic nuclei research and stress the relevance of blue outliers to feedback and host galaxy evolution.

  13. Jiangxi Copper Corporation Builds 900,000-Ton Copper Production Capacity

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>The Eastward Refined Copper Expansion Pro- ject of Guixi Smelting Plant under Jiangxi Copper Corporation has output its first lot of Copper cathode,marking the company’s pos- session of a 900,000-ton copper production ca- pacity.Thus the company further strengthens its position as the top 3 of the copper world.

  14. Unravelling the Chemical Nature of Copper Cuprizone

    OpenAIRE

    Messori, L.; Casini, A.; C.Gabbiani; Sorace, L.; Muniz-Miranda, M.; Zatta, P

    2007-01-01

    During the last 50 years, formation of the highly chromogenic copper cuprizone complex has been exploited for spectrophotometric determinations of copper although the precise chemical nature of the resulting species has never been ascertained; we eventually show here, in contrast to current opinion, that copper cuprizone is a copper(III) complex.

  15. Secondary Copper Industry Entered Rapid Growth Period

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    In China’s copper output,secondary copper accounts for about 40%,for power cable industry,the usage percentage of secondary copper is about 50%.Under the favorable policy of the government to vigorously support recycling industry,secondary copper rod enterprises begin to expand,and are confident toward the industry’s potentials.

  16. 49 CFR 192.279 - Copper pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Copper pipe. 192.279 Section 192.279 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... Copper pipe. Copper pipe may not be threaded except that copper pipe used for joining screw fittings...

  17. Paradoxical Condensation of Copper with Elevated β-Amyloid in Lipid Rafts under Cellular Copper Deficiency Conditions: IMPLICATIONS FOR ALZHEIMER DISEASE*

    OpenAIRE

    Hung, Ya Hui; Robb, Elysia L.; Volitakis, Irene; Ho, Michael; Evin, Genevieve; Li, Qiao-Xin; Janetta G Culvenor; Masters, Colin L.; Cherny, Robert A.; Bush, Ashley I.

    2009-01-01

    Redox-active copper is implicated in the pathogenesis of Alzheimer disease (AD), β-amyloid peptide (Aβ) aggregation, and amyloid formation. Aβ·copper complexes have been identified in AD and catalytically oxidize cholesterol and lipid to generate H2O2 and lipid peroxides. The site and mechanism of this abnormality is not known. Growing evidence suggests that amyloidogenic processing of the β-amyloid precursor protein (APP) occurs in lipid rafts, membrane microdomains enriched in cholesterol. ...

  18. MECHANISM OF THE OXIDATION OF HEMOGLOBIN BY COPPER (II COMPLXES

    Directory of Open Access Journals (Sweden)

    M. BAYATI

    1994-07-01

    Full Text Available An outer sphere electron transfer mechanism by which human hemoglobin reduces the complexes of copper(II and, in turn, is oxidized to methemoglobin has been characterized. We have found that the rate of oxidation of hemoglobin is a function of pH, temperature, concentration of copper(II, and the environment of the hemoglobin. Prior to oxidation, copper(II complex binds to specific sites on the surface of the protein by losing one or more of its ligands, forming a ternary complex. This process is followed by electron transfer between the Cu(II and Fe(H with the Cu(II-deoxyhemoglobin being the active intermediate. The dominant factors which govern the rate of oxidation of hemoglobin by coppcr(I I complexes seem to be the stability constant of the Cu(II complexes and the overall redox potential of the ternary complex.

  19. Secondary Copper Consumption and Location in China

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正> China is short of copper resources and is alsothe second largest copper consuming country inthe world.The way to overcome the contradic-tion between the resource shortage and fastgrowth in consumption is to import copper rawmaterial in large quantities.Since the 1990’s,China’s import quantity of copper scrap hasincreased considerably.During the last twoyears,China has imported copper scrap worthof US$2.25 billion,1.32 times of the value ofimported copper concentrates in the same pe-riod.China is one of the biggest copper scrap

  20. Blue Ribbon Panel Report - BRP - Cancer Moonshot

    Science.gov (United States)

    The Blue Ribbon Panel Report outlines 10 recommendations to accelerate progress against cancer. The panel was established to ensure that the Cancer Moonshot's approaches are grounded in the best science.

  1. Blue Ribbon Panel 2016 Video Playlist

    Science.gov (United States)

    Blue Ribbon Panel members discuss recommendations from the panel report that was presented to the National Cancer Advisory Board on September 7, 2016. The playlist includes an overview video and 10 videos on the specific recommendations.

  2. Elementary Theorems Regarding Blue Isocurvature Perturbations

    CERN Document Server

    Chung, Daniel J H

    2015-01-01

    Blue CDM-photon isocurvature perturbations are attractive in terms of observability and may be typical from the perspective of generic mass relations in supergravity. We present and apply three theorems useful for blue isocurvature perturbations arising from linear spectator scalar fields. In the process, we give a more precise formula for the blue spectrum associated with the work of 0904.3800, which can in a parametric corner give a factor of O(10) correction. We explain how a conserved current associated with Peccei-Quinn symmetry plays a crucial role and explicitly plot several example spectra including the breaks in the spectra. We also resolve a little puzzle arising from a naive multiplication of isocurvature expression that sheds light on the gravitational imprint of the adiabatic perturbations on the fields responsible for blue isocurvature fluctuations.

  3. Properties of blue-stained wood

    Directory of Open Access Journals (Sweden)

    Miha Humar

    2008-07-01

    Full Text Available Discoloration of wood is frequently caused by blue-stain fungi. Among them Aureobasidium pullulans and Sclerophoma pithyophila are reported as the most important staining organism. In previous researches, it was generally considered that blue-stain fungi do not influence mechanical properties. However, there were some opposite results published as well. In order to elucidate this issue, specimens made of Scots pine (Pinus sylvestris sapwood were exposed to two blue stain fungi A. pullulans and S. pithyophila for periods between two and eight weeks. FTIR, weight, colour and non-destructive modulus of elasticity measurements were performed before and after exposure. The results showed that blue stain fungi, besides considerable discoloration, do not cause any significant damage to wood. Surprisingly the non-destructive MoE analysis showed that modulus of elasticity even slightly increase after fungal exposure.

  4. Differential sexual survival of Drosophila melanogaster on copper sulfate.

    Science.gov (United States)

    Balinski, Michael A; Woodruff, Ronny C

    2017-04-01

    Based on studies of the influence of X-chromosomes on the viability of Drosophila melanogaster exposed to cadmium, and on the role of X-linked genes on copper homeostasis, we examined the effect of copper sulfate (CuSO4) on offspring viability using three independent, inbred D. melanogaster crosses (ensuring identical autosomes for males and females within each cross). Each cross was performed with attached X-chromosome females and males with a single X-chromosome. As female D. melanogaster have less metallothionein RNA expression than males, we predicted fewer female offspring than male offspring in crosses exposed to CuSO4, even though females have two copies of X-chromosome genes, possibly resulting in overdominant heterozygosity. In two of three crosses, CuSO4 caused significantly higher numbers of male offspring compared to female offspring. We hypothesized that these gender-based viability differences to copper exposure are caused by X-chromosome ploidy and X-linked genetic variation affecting metallothionein expression. Observed differential offspring viability responses among crosses to copper exposure also showed that different genetic backgrounds (autosomal and/or X-chromosome) can result in significant differences in heavy metal and metallothionein regulation. These results suggest that the effect of copper on offspring viability depends on both genetic background and gender, as both factors can affect the regulation of metallothionein proteins as well as homeostasis of biologically necessary heavy metals.

  5. Afghanistan: Green-on-Blue Attacks

    Science.gov (United States)

    2013-05-02

    Afghanistan, December 2012, p 35 15 Yousafzai, Sami and Moreau , Ron, http://www.thedailybeast.com/newsweek/2012/08/26/ afghanistan-green-on-blue-killings...spike-insider-attacks- stress-ramadan-fasting, 24 August 2012 37 Yousafzai, Sami and Moreau , Ron, http://www.thedailybeast.com/newsweek/2012/08/26...afghanistan-green-on-blue-killings- explained.html, Afghanistan: ‘Green on Blue’ Killings Explained, 27 August 2012 38 Yousafzai, Sami and Moreau , Ron

  6. An Introduction to Copper Deposits in China

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    There are 11 genetic types of copper deposit in China, three of which (porphyry,contact metasomatic and VMS types) are the most important. The copper deposits distribute widely both temporally and spatially in China. The features of copper ores in China are mostly poor in copper tenor and complex in metal associated. The copper metallogeny in China predominantly occurs in three metallogenic megadomains, namely the circum-Pacific, the paleo-Asian and the Tethys-Himalayan.

  7. COX19 mediates the transduction of a mitochondrial redox signal from SCO1 that regulates ATP7A-mediated cellular copper efflux

    OpenAIRE

    Leary, Scot C; Cobine, Paul A.; Nishimura, Tamiko; Verdijk, Robert M; de Krijger, Ronald; Coo, René; Tarnopolsky, Mark A.; Winge, Dennis R; Eric A Shoubridge

    2013-01-01

    SCO1 and SCO2 are metallochaperones whose principal function is to add two copper ions to the catalytic core of cytochrome c oxidase (COX). However, affected tissues of SCO1 and SCO2 patients exhibit a combined deficiency in COX activity and total copper content, suggesting additional roles for these proteins in the regulation of cellular copper homeostasis. Here we show that both the redox state of the copper-binding cysteines of SCO1 and the abundance of SCO2 correlate with cellular copper ...

  8. Copper transport systems are involved in multidrug resistance and drug transport.

    Science.gov (United States)

    Furukawa, Tatsuhiko; Komatsu, Masaharu; Ikeda, Ryuji; Tsujikawa, Kazutake; Akiyama, Shin-ichi

    2008-01-01

    Copper is an essential trace element and several copper containing proteins are indispensable for such processes as oxidative respiration, neural development and collagen remodeling. Copper metabolism is precisely regulated by several transporters and chaperone proteins. Copper Transport Protein 1 (CTR1) selectively uptakes copper into cells. Subsequently three chaperone proteins, HAH1 (human atx1 homologue 1), Cox17p and CCS (copper chaperone for superoxide dismutase) transport copper to the Golgi apparatus, mitochondria and copper/zinc superoxide dismutase respectively. Defects in the copper transporters ATP7A and ATP7B are responsible for Menkes disease and Wilson's disease respectively. These proteins transport copper via HAH1 to the Golgi apparatus to deliver copper to cuproenzymes. They also prevent cellular damage from an excess accumulation of copper by mediating the efflux of copper from the cell. There is increasing evidence that copper transport mechanisms may play a role in drug resistance. We, and others, found that ATP7A and ATP7B are involved in drug resistance against the anti-tumor drug cis-diamminedichloroplatinum (II) (CDDP). A relationship between the expression of ATP7A or ATP7B in tumors and CDDP resistance is supported by clinical studies. In addition, the copper uptake transporter CTR1 has also been reported to play a role in CDDP sensitivity. Furthermore, we have recently found that the effect of ATP7A on drug resistance is not limited to CDDP. Using an ex vivo drug sensitivity assay, the histoculture drug response assay (HDRA), the expression of ATP7A in human surgically resected colon cancer cells correlated with sensitivity to 7-ethyl-10-hydroxy-camptothecin (SN-38). ATP7A-overexpressing cells are resistant to many anticancer drugs including SN-38, 7-ethyl-10-[4-(1-piperidino)-1-piperidino] carbonyloxycamptothecin (CPT-11), vincristine, paclitaxel, etoposide, doxorubicin (Dox), and mitoxantron. The mechanism by which ATP7A and copper

  9. Distribution and chemical forms of copper in the root cells of castor seedlings and their tolerance to copper phytotoxicity in hydroponic culture.

    Science.gov (United States)

    Kang, Wei; Bao, Jianguo; Zheng, Jin; Hu, Hongqin; Du, Jiangkun

    2015-05-01

    The subcellular localization and chemical forms of copper in castor (Ricinus communis L.) seedlings grown in hydroponic nutrient solution were identified by chemical extraction, transmission electron microscopy, and Fourier transform infrared spectroscopy. The wild castor seeds were harvested from an abandoned copper mine in Tonglu Mountain, Daye City of Hubei Province, China. The results revealed that (1) the seedlings grew naturally in MS liquid medium with 40.00 mg kg(-1) CuSO4, in which the seedling growth rate and biomass index were 0.14 and 1.23, respectively, which were the highest values among all the treatments. The copper content in castor seedlings increased along with elevated CuSO4 concentration in the medium, reaching a maximum value of 16 570.12 mg kg(-1)(DW) when exposed to 60.00 mg L(-1) CuSO4, where 91.31% of the copper was accumulated in roots. (2) The copper existed in various chemical forms in the roots of the castor seedlings. Copper of 67.66% was extracted from the components of cell walls, such as exchangeable acidic polar compounds, cellulose and lignin, protein and pectin, and less concentrated in cell cytoplasm and nuclei. (3) Furthermore, the root cell walls were thickened when the castor seedlings exposed to CuSO4, with a large amount of high-density electron bodies, attached to the thickened cell walls. In the cell walls, most copper was bound to the carboxyl (-COOH) and hydroxyl (-OH) groups of acidic polar compounds, cellulose, hemicellulose, and polysaccharides. The conclusion showed that castor exhibited a strong tolerance to copper, the copper were accumulated mainly in the root cell, the root cell walls of castor were the major location of patience and detoxification in copper stress.

  10. Influence of estrogens on copper indicators: in vivo and in vitro studies.

    Science.gov (United States)

    Arredondo, Miguel; Núñez, Héctor; López, Guadalupe; Pizarro, Fernando; Ayala, Mariana; Araya, Magdalena

    2010-06-01

    Classic copper indicators are not sensitive and specific for detecting excess copper exposure when this is higher than customary but not markedly elevated. Serum copper and ceruloplasmin (Cp) are the most commonly used indicators to assess nutritional status of copper. The objective of this paper was to study the influence of estrogens on these indicators and others used to assess early effects of excess copper exposure in humans and the expression of a set of copper related proteins in a hepatic cellular model. For the studies in humans, 107 healthy participants (18-50 years) were allocated as follows: group 1 (n = 39), women assessed on day 7 of their hormonal cycle; group 2 (n = 34), women assessed on day 21 of their hormonal cycle, and group 3 (n = 34, comparison group), healthy men. Participants received 8 mg Cu/day (as copper sulfate) during 6 months. Serum Cp and Cu, Cu-Zn-superoxide dismutase activity, liver function indicators [aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma glutamyltransferase (GGT)], and serum Fe and Zn concentrations were measured monthly. In addition, the influence of estradiol on intracellular total copper content, hctr1, dmt1 and shbg mRNA abundance and hCTR1, and DMT1 expression was measured in HepG2 cells. Serum Cu, Fe, and Zn and liver aminotransferases but not Cu-Zn-superoxide dismutase varied depending on sex. Fe nutrition indicators, GGT, and ALT activities showed significant differences between the hormonal phases. Cellular experiments showed that estradiol increased cellular Cu concentration and hCTR1 and DMT1 mRNA expression and changed these proteins expression patterns. Estradiols significantly influence the responses to copper at the whole body and the cellular levels, suggesting that they help maintaining copper availability for metabolic needs.

  11. Coordination of Copper to the Membrane-Bound Form of α-Synuclein

    Energy Technology Data Exchange (ETDEWEB)

    Dudzik, Christopher G.; Walter, Eric D.; Abrams, Benjamin S.; Jurica, Melissa S.; Millhauser, Glenn L.

    2013-01-01

    Aggregation of the 140 amino acid protein α-synuclein (α-syn) is linked to the development of Parkinson's disease (PD). α-Syn is a copper binding protein with potential function as a regulator of metal dependent redox activity. Epidemiological studies suggest that human exposure to excess copper increases the incidence of PD. α-Syn exists in both solution and membrane bound forms. Previous work evaluated the Cu2+ uptake for α-syn in solution and identified Met1-Asp2 and His50 as primary contributors to the coordination shell, with a dissociation constant of approximately 0.1 nM. When bound to the membrane bilayer, α-syn takes on a predominantly helical conformation, which spatially separates His50 from the protein N-terminus and is therefore incompatible with the copper coordination geometry of the solution state. Here we use circular dichroism and electron paramagnetic resonance (continuous wave and pulsed) to evaluate copper coordination to the membrane bound form of α-syn. In this molecular environment, Cu2+ binds exclusively to the protein N-terminus (Met1-Asp2) with no participation from His50. Copper does not alter the membrane bound α-syn conformation, or enhance the protein's release from the bilayer. The Cu2+ affinity is similar to that identified for solution α-syn suggesting that copper coordination is retained in the membrane. Consideration of these results suggests that copper exerts its greatest conformational affect on the solution form of α-syn and this species may therefore be precursor to PD arising from environmental copper exposure.

  12. Majorana Electroformed Copper Mechanical Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Overman, Nicole R.; Overman, Cory T.; Kafentzis, Tyler A.; Edwards, Danny J.; Hoppe, Eric W.

    2012-04-30

    The MAJORANA DEMONSTRATOR is a large array of ultra-low background high-purity germanium detectors, enriched in 76Ge, designed to search for zero-neutrino double-beta decay. The DEMONSTRATOR will utilize ultra high purity electroformed copper for a variety of detector components and shielding. A preliminary mechanical evaluation was performed on the Majorana prototype electroformed copper material. Several samples were removed from a variety of positions on the mandrel. Tensile testing, optical metallography, scanning electron microscopy, and hardness testing were conducted to evaluate mechanical response. Analyses carried out on the Majorana prototype copper to this point show consistent mechanical response from a variety of test locations. Evaluation shows the copper meets or exceeds the design specifications.

  13. In utero copper treatment for Menkes disease associated with a severe ATP7A mutation.

    Science.gov (United States)

    Haddad, Marie Reine; Macri, Charles J; Holmes, Courtney S; Goldstein, David S; Jacobson, Beryl E; Centeno, Jose A; Popek, Edwina J; Gahl, Willam A; Kaler, Stephen G

    2012-09-01

    Menkes disease is a lethal X-linked recessive neurodegenerative disorder of copper transport caused by mutations in ATP7A, which encodes a copper-transporting ATPase. Early postnatal treatment with copper injections often improves clinical outcomes in affected infants. While Menkes disease newborns appear normal neurologically, analyses of fetal tissues including placenta indicate abnormal copper distribution and suggest a prenatal onset of the metal transport defect. In an affected fetus whose parents found termination unacceptable and who understood the associated risks, we began in utero copper histidine treatment at 31.5 weeks gestational age. Copper histidine (900 μg per dose) was administered directly to the fetus by intramuscular injection (fetal quadriceps or gluteus) under ultrasound guidance. Percutaneous umbilical blood sampling enabled serial measurement of fetal copper and ceruloplasmin levels that were used to guide therapy over a four-week period. Fetal copper levels rose from 17 μg/dL prior to treatment to 45 μg/dL, and ceruloplasmin levels from 39 mg/L to 122 mg/L. After pulmonary maturity was confirmed biochemically, the baby was delivered at 35.5 weeks and daily copper histidine therapy (250 μg sc b.i.d.) was begun. Despite this very early intervention with copper, the infant showed hypotonia, developmental delay, and electroencephalographic abnormalities and died of respiratory failure at 5.5 months of age. The patient's ATP7A mutation (Q724H), which severely disrupted mRNA splicing, resulted in complete absence of ATP7A protein on Western blots. These investigations suggest that prenatally initiated copper replacement is inadequate to correct Menkes disease caused by severe loss-of-function mutations, and that postnatal ATP7A gene addition represents a rational approach in such circumstances.

  14. Reduced glutathione biosynthesis in Drosophila melanogaster causes neuronal defects linked to copper deficiency.

    Science.gov (United States)

    Mercer, Stephen W; La Fontaine, Sharon; Warr, Coral G; Burke, Richard

    2016-05-01

    Glutathione (GSH) is a tripeptide often considered to be the master antioxidant in cells. GSH plays an integral role in cellular redox regulation and is also known to have a role in mammalian copper homeostasis. In vitro evidence suggests that GSH is involved in copper uptake, sequestration and efflux. This study was undertaken to further investigate the roles that GSH plays in neuronal copper homeostasis in vivo, using the model organism Drosophila melanogaster. RNA interference-mediated knockdown of the Glutamate-cysteine ligase catalytic subunit gene (Gclc) that encodes the rate-limiting enzyme in GSH biosynthesis was utilised to genetically deplete GSH levels. When Gclc was knocked down in all neurons, this caused lethality, which was partially rescued by copper supplementation and was exacerbated by additional knockdown of the copper uptake transporter Ctr1A, or over-expression of the copper efflux transporter ATP7. Furthermore, when Gclc was knocked down in a subset of neuropeptide-producing cells, this resulted in adult progeny with unexpanded wings, a phenotype previously associated with copper dyshomeostasis. In these cells, Gclc suppression caused a decrease in axon branching, a phenotype further enhanced by ATP7 over-expression. Therefore, we conclude that GSH may play an important role in regulating neuronal copper levels and that reduction in GSH may lead to functional copper deficiency in neurons in vivo. We provide genetic evidence that glutathione (GSH) levels influence Cu content or distribution in vivo, in Drosophila neurons. GSH could be required for binding Cu imported by Ctr1A and distributing it to chaperones, such as Mtn, CCS and Atox1. Alternatively, GSH could modify the copper-binding and transport activities of Atox1 and the ATP7 efflux protein via glutathionylation of copper-binding cysteines.

  15. Biomarkers of waterborne copper exposure in the guppy Poecilia vivipara acclimated to salt water

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Anderson Abel de Souza [Universidade Federal do Rio Grande, Programa de Pós-Graduação em Oceanografia Biológica, Av. Itália km 8, 96201-900 Rio Grande, Rio Grande do Sul (Brazil); Hoff, Mariana Leivas Müller [Universidade Federal do Rio Grande, Instituto de Ciências Biológicas, Av. Itália km 8, 96201-900 Rio Grande, Rio Grande do Sul (Brazil); Klein, Roberta Daniele [Universidade Federal do Rio Grande, Programa de Pós-Graduação em Ciências Fisiológicas – Fisiologia Animal Comparada, Av. Itália km 8, 96201-900 Rio Grande, Rio Grande do Sul (Brazil); Cardozo, Janaina Goulart [Universidade Federal do Rio Grande, Instituto de Ciências Biológicas, Av. Itália km 8, 96201-900 Rio Grande, Rio Grande do Sul (Brazil); Giacomin, Marina Mussoi [Universidade Federal do Rio Grande, Programa de Pós-Graduação em Ciências Fisiológicas – Fisiologia Animal Comparada, Av. Itália km 8, 96201-900 Rio Grande, Rio Grande do Sul (Brazil); Pinho, Grasiela Lopes Leães [Universidade Federal do Rio Grande, Instituto de Oceanografia, Av. Itália km 8, 96201-900 Rio Grande, Rio Grande do Sul (Brazil); and others

    2013-08-15

    Highlights: •Acute effects of waterborne copper were evaluated in the estuarine guppy Poecilia vivipara. •Fishes were acutely exposed to waterborne copper in salt water. •Waterborne copper affects the response of several biochemical and genetic endpoints. •Catalase, reactive oxygen species, antioxidant capacity and lipid peroxidation are responsive to copper exposure. •Copper exposure induces DNA damages in fish erythrocytes. -- Abstract: The responses of a large suite of biochemical and genetic parameters were evaluated in tissues (liver, gills, muscle and erythrocytes) of the estuarine guppy Poecilia vivipara exposed to waterborne copper in salt water (salinity 24 ppt). Activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione reductase, and glutathione S-transferase), metallothionein-like protein concentration, reactive oxygen species (ROS) content, antioxidant capacity against peroxyl radicals (ACAP), and lipid peroxidation (LPO) were evaluated in liver, gills, and muscle. Comet assay score and nuclear abnormalities and micronucleated cell frequency were analyzed in peripheral erythrocytes. The responses of these parameters were evaluated in fish exposed (96 h) to environmentally relevant copper concentrations (5, 9 and 20 μg L{sup −1}). In control and copper-exposed fish, no mortality was observed over the experimental period. Almost all biochemical and genetic parameters proved to be affected by waterborne copper exposure. However, the response of catalase activity in liver, ROS, ACAP and LPO in muscle, gills and liver, and DNA damages in erythrocytes clearly showed to be dependent on copper concentration in salt water. Therefore, the use of these parameters could be of relevance in the scope of biomonitoring programs in salt water environments contaminated with copper.

  16. The Revovery of Copper and Cobalt from Oxidized Copper Ore and Converter Slag

    OpenAIRE

    ZİYADANOĞULLARI, Berrin; ZİYADANOĞULLARI, Recep

    1999-01-01

    The aim of this study was to develop a method for obtaining copper and cobalt from oxidized copper ore and converter slag. In order to convert the copper and cobalt into sulfate compounds the main step was to roast the samples obtained by sulfurization and transfer the samples into solution. First the oxidized copper ore was roasted, followed by the mixture of converter slag and oxidized copper ore. Since the levels of copper and cobalt were low, the sulfurization process was carri...

  17. Genome Sequences of Two Copper-Resistant Escherichia coli Strains Isolated from Copper-Fed Pigs

    DEFF Research Database (Denmark)

    Lüthje, Freja L.; Hasman, Henrik; Aarestrup, Frank Møller;

    2014-01-01

    The draft genome sequences of two copper-resistant Escherichia coli strains were determined. These had been isolated from copper-fed pigs and contained additional putative operons conferring copper and other metal and metalloid resistances.......The draft genome sequences of two copper-resistant Escherichia coli strains were determined. These had been isolated from copper-fed pigs and contained additional putative operons conferring copper and other metal and metalloid resistances....

  18. Formation of copper-indium-selenide and/or copper-indium-gallium-selenide films from indium selenide and copper selenide precursors

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Calvin J [Lakewood, CO; Miedaner, Alexander [Boulder, CO; Van Hest, Maikel [Lakewood, CO; Ginley, David S [Evergreen, CO; Nekuda, Jennifer A [Lakewood, CO

    2011-11-15

    Liquid-based indium selenide and copper selenide precursors, including copper-organoselenides, particulate copper selenide suspensions, copper selenide ethylene diamine in liquid solvent, nanoparticulate indium selenide suspensions, and indium selenide ethylene diamine coordination compounds in solvent, are used to form crystalline copper-indium-selenide, and/or copper indium gallium selenide films (66) on substrates (52).

  19. Hereditary iron and copper deposition

    DEFF Research Database (Denmark)

    Aaseth, Jan; Flaten, Trond Peder; Andersen, Ole

    2007-01-01

    Hereditary deposition of iron (primary haemochromatosis) or copper (Wilson's disease) are autosomal recessive metabolic disease characterized by progressive liver pathology and subsequent involvement of various other organs. The prevalence of primary haemochromatosis is approximately 0.5%, about...... can be successfully treated, emphasizing the importance of early diagnosis. Serum ferritin values, transferrin saturation and genetic analysis are used when diagnosing haemochromatosis. The diagnostics of Wilson's disease depends on the use of urinary copper values, serum ceruloplasmin and liver...

  20. Novel thermochromism relating to supramolecular cuprophilic interaction: design, synthesis, and luminescence of copper(I) pyrazolate trimer and polymer.

    Science.gov (United States)

    Zhang, Jing-Xiang; He, Jun; Yin, Ye-Gao; Hu, Mei-Hong; Li, Dan; Huang, Xiao-Chun

    2008-05-05

    Solvothermal reactions of 4-(pyrid-4'-yl)-3,5-dimethylpyrazole (HPpz) with CuBr in two mixed solvents, NH3.H2O/EtOH and NH3.H2O/MeCN, afforded respectively a copper(I) trimer, [Cu(Ppz)]3(1), and a polymer, {[Cu(Ppz)]3[CuCN] 3} (2), both containing the [Cu(Ppz)]3 entity as a building block. The products were found to be photoluminescent and, more interestingly, when cooled from room temperature to 10 K, they showed a blue shift followed by a red shift (hereafter shortened to a red-after-blue shift) of emission.

  1. Regulation of copper and iron homeostasis by metal chelators: a possible chemotherapy for Alzheimer's disease.

    Science.gov (United States)

    Robert, Anne; Liu, Yan; Nguyen, Michel; Meunier, Bernard

    2015-05-19

    With the increase of life expectancy of humans in more than two-thirds of the countries in the World, aging diseases are becoming the frontline health problems. Alzheimer's disease (AD) is now one of the major challenges in drug discovery, since, with the exception of memantine in 2003, all clinical trials with drug candidates failed over the past decade. If we consider that the loss of neurons is due to a high level of oxidative stress produced by nonregulated redox active metal ions like copper linked to amyloids of different sizes, regulation of metal homeostasis is a key target. The difficulty for large copper-carrier proteins to directly extract copper ions from metalated amyloids might be considered as being at the origin of the rupture of the copper homeostasis regulation in AD brains. So, there is an urgent need for new specific metal chelators that should be able to regulate the homeostasis of metal ions, specially copper and iron, in AD brains. As a consequence of that concept, chelators promoting metal excretion from brain are not desired. One should favor ligands able to extract copper ions from sinks (amyloids being the major one) and to transfer these redox-active metal ions to copper-carrier proteins or copper-containing enzymes. Obviously, the affinity of these chelators for the metal ion should not be a sufficient criterion, but the metal specificity and the ability of the chelators to release the metal under specific biological conditions should be considered. Such an approach is still largely unexplored. The requirements for the chelators are very high (ability to cross the brain-blood barrier, lack of toxicity, etc.), few chemical series were proposed, and, among them, biochemical or biological data are scarce. As a matter of fact, the bioinorganic pharmacology of AD represents less than 1% of all articles dedicated to AD drug research. The major part of these articles deals with an old and rather toxic drug, clioquinol and related analogs, that

  2. New biosensor for detection of copper ions in water based on immobilized genetically modified yeast cells.

    Science.gov (United States)

    Vopálenská, Irena; Váchová, Libuše; Palková, Zdena

    2015-10-15

    Contamination of water by heavy metals represents a potential risk for both aquatic and terrestrial organisms, including humans. Heavy metals in water resources can come from various industrial activities, and drinking water can be ex-post contaminated by heavy metals such as Cu(2+) from house fittings (e.g., water reservoirs) and pipes. Here, we present a new copper biosensor capable of detecting copper ions at concentrations of 1-100 μM. This biosensor is based on cells of a specifically modified Saccharomyces cerevisiae strain immobilized in alginate beads. Depending on the concentration of copper, the biosensor beads change color from white, when copper is present in concentrations below the detection limit, to pink or red based on the increase in copper concentration. The biosensor was successfully tested in the determination of copper concentrations in real samples of water contaminated with copper ions. In contrast to analytical methods or other biosensors based on fluorescent proteins, the newly designed biosensor does not require specific equipment and allows the quick detection of copper in many parallel samples.

  3. Comparison of Alcian Blue, Trypan Blue, and Toluidine Blue for Visualization of the Primo Vascular System Floating in Lymph Ducts

    Directory of Open Access Journals (Sweden)

    Da-Un Kim

    2015-01-01

    Full Text Available The primo vascular system (PVS, floating in lymph ducts, was too transparent to be observed by using a stereomicroscope. It was only detectable with the aid of staining dyes, for instance, Alcian blue, which was injected into the lymph nodes. Some dyes were absorbed preferentially by the PVS than the lymph wall. It remains a standing problem to know what dyes are absorbed better by the PVS than the lymph walls. Such information would be useful to unravel the biochemical properties of the PVS that are badly in need for obtaining large amount of PVS specimens. In the current work we tried two other familiar dyes which were used in PVS research before. We found that Trypan blue and toluidine blue did not visualize the PVS. Trypan blue was cleared by the natural washing. Toluidine blue did not stain the PVS, but it did leave stained spots in the lymph wall and its surrounding tissues, and it leaked out of the lymph wall to stain surrounding connective tissues. These completely different behaviors of the three dyes were found for the first time in the current work and provide valuable information to elucidate the mechanism through which some special dyes stained the PVS preferentially compared to the lymphatic wall.

  4. Analysis of green copper pigments in illuminated manuscripts by micro-Raman spectroscopy.

    Science.gov (United States)

    Gilbert, B; Denoël, S; Weber, G; Allart, D

    2003-10-01

    In the majority of the literature describing green coloured materials used on ancient painting layers (15th or 16th century), two copper greens are mainly cited: malachite [CuCOr3 x Cu(OH)2] and verdigris [Cu(CH3COO)2 x [Cu(OH)2]3 x 2H2O]. It is shown, by micro-Raman spectroscopy, that the artists were actually employing more than these two copper greens, in particular various copper sulfates, among which the most common pigment found is posnjakite [CuSO4 x 3Cu(OH)2 x H2O]. In contrast to the PIXE (particle induced X-ray emission) technique, Raman spectroscopy is a technique of choice, able to distinguish not only a copper sulfate from a carbonate or acetate but also the different sulfates themselves; in this respect, we found that the high wavenumber region (2800-4000 cm(-1)), characteristic of H2O vibrations, is of particular interest. It is also shown that numerous green areas were created with mixtures of a copper sulfate mixed with other pigments, for instance to enhance the colour depth. Finally, in some cases, no green pigment is actually employed but the colour is obtained by intimately mixing yellow and blue pigments. All these results led to a new look at the pigments which were in use on the palettes of the ancient artists.

  5. Characterization of a Highly Thermostable and Organic Solvent-Tolerant Copper-Containing Polyphenol Oxidase with Dye-Decolorizing Ability from Kurthia huakuii LAM0618T

    Science.gov (United States)

    Guo, Xiang; Zhou, Shan; Wang, Yanwei; Song, Jinlong; Wang, Huimin; Kong, Delong; Zhu, Jie; Dong, Weiwei; He, Mingxiong; Hu, Guoquan; Ruan, Zhiyong

    2016-01-01

    Laccases are green biocatalysts that possess attractive advantages for the treatment of resistant environmental pollutants and dye effluents. A putative laccase-like gene, laclK, encoding a protein of 29.3 kDa and belonging to the Cu-oxidase_4 superfamily, was cloned and overexpressed in Escherichia coli. The purified recombinant protein LaclK (LaclK) was able to oxidize typical laccase substrates such as 2,6-dimethoxyphenol and l-dopamine. The characteristic adsorption maximums of typical laccases at 330 nm and 610 nm were not detected for LaclK. Cu2+ was essential for substrate oxidation, but the ratio of copper atoms/molecule of LaclK was determined to only be 1:1. Notably, the optimal temperature of LaclK was 85°C with 2,6-dimethoxyphenol as substrates, and the half-life approximately 3 days at 80°C. Furthermore, 10% (v/v) organic solvents (methanol, ethanol, isopropyl alcohol, butyl alcohol, Triton x-100 or dimethyl sulfoxide) could promote enzymatic activity. LaclK exhibited wide-spectrum decolorization ability towards triphenylmethane dyes, azo dyes and aromatic dyes, decolorizing 92% and 94% of Victoria Blue B (25 μM) and Ethyl Violet (25 μM), respectively, at a concentration of 60 U/L after 1 h of incubation at 60°C. Overall, we characterized a novel thermostable and organic solvent-tolerant copper-containing polyphenol oxidase possessing dye-decolorizing ability. These unusual properties make LaclK an alternative for industrial applications, particularly processes that require high-temperature conditions. PMID:27741324

  6. Variations on the "Blue-Bottle" Demonstration Using Food Items That Contain FD&C Blue #1

    Science.gov (United States)

    Staiger, Felicia A.; Peterson, Joshua P.; Campbell, Dean J.

    2015-01-01

    Erioglaucine dye (FD&C Blue #1) can be used instead of methylene blue in the classic "blue-bottle" demonstration. Food items containing FD&C Blue #1 and reducing species such as sugars can therefore be used at the heart of this demonstration, which simply requires the addition of strong base such as sodium hydroxide lye.

  7. 21 CFR 133.184 - Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk. 133.184 Section 133.184 Food and Drugs FOOD AND DRUG ADMINISTRATION..., sheep's milk blue-mold, and blue-mold cheese from sheep's milk. (a) Description. (1) Roquefort...

  8. COX19 mediates the transduction of a mitochondrial redox signal from SCO1 that regulates ATP7A-mediated cellular copper efflux

    Science.gov (United States)

    Leary, Scot C.; Cobine, Paul A.; Nishimura, Tamiko; Verdijk, Robert M.; de Krijger, Ronald; de Coo, René; Tarnopolsky, Mark A.; Winge, Dennis R.; Shoubridge, Eric A.

    2013-01-01

    SCO1 and SCO2 are metallochaperones whose principal function is to add two copper ions to the catalytic core of cytochrome c oxidase (COX). However, affected tissues of SCO1 and SCO2 patients exhibit a combined deficiency in COX activity and total copper content, suggesting additional roles for these proteins in the regulation of cellular copper homeostasis. Here we show that both the redox state of the copper-binding cysteines of SCO1 and the abundance of SCO2 correlate with cellular copper content and that these relationships are perturbed by mutations in SCO1 or SCO2, producing a state of apparent copper overload. The copper deficiency in SCO patient fibroblasts is rescued by knockdown of ATP7A, a trans-Golgi, copper-transporting ATPase that traffics to the plasma membrane during copper overload to promote efflux. To investigate how a signal from SCO1 could be relayed to ATP7A, we examined the abundance and subcellular distribution of several soluble COX assembly factors. We found that COX19 partitions between mitochondria and the cytosol in a copper-dependent manner and that its knockdown partially rescues the copper deficiency in patient cells. These results demonstrate that COX19 is necessary for the transduction of a SCO1-dependent mitochondrial redox signal that regulates ATP7A-mediated cellular copper efflux. PMID:23345593

  9. Cyclodextrins 3-Functionalized with 8-Hydroxyquinolines: Copper-Binding Ability and Inhibition of Synuclein Aggregation.

    Science.gov (United States)

    Oliveri, Valentina; Sgarlata, Carmelo; Vecchio, Graziella

    2016-09-06

    Neurodegenerative diseases such as Parkinson's and Alzheimer's diseases are multifactorial disorders related to protein aggregation, metal dyshomeostasis, and oxidative stress. To advance understanding in this area and to contribute to therapeutic development, many efforts have been directed at devising suitable agents that can target metal ions associated with relevant biomolecules such as α-synuclein. This paper presents a new cyclodextrin-8-hydroxyquinoline conjugate and discusses the properties of four cyclodextrins 3-functionalized with 8-hydroxyquinoline as copper(II) chelators and inhibitors of copper-induced synuclein aggregation. The encouraging results establish the potential of cyclodextrin-8-hydroxyquinoline conjugates as chelators for the control of copper toxicity.

  10. "Blue-Collar Blues" uurib töösuhteid uutes oludes / Janar Ala

    Index Scriptorium Estoniae

    Ala, Janar, 1979-

    2009-01-01

    Tööproblemaatikat käsitlev näitus "Blue-Collar Blues" Tallinna Kunstihoones ja Tallinna Kunstihoone galeriis 31. jaanuarini 2010, kuraator Anders Härm. Lähemalt belgia-mehhiko kunstniku Francis Alys'e videost, austria kunstniku Oliver Ressleri ning venetsueela-saksa politoloogi Dario Azzelini videost "Viis tehast. Tööliste kontroll Venezuelas"

  11. 75 FR 65525 - Anthem Blue Cross Blue Shield, Claim Management Services, Inc. Operations, a Division of...

    Science.gov (United States)

    2010-10-25

    ... Management Services, Inc. Operations, a Division of Wellpoint, Inc., Green Bay, Wisconsin (the subject firm... Employment and Training Administration Anthem Blue Cross Blue Shield, Claim Management Services, Inc. Operations, a Division of Wellpoint, Inc., Green Bay, WI; Notice of Negative Determination...

  12. The many “faces” of copper in medicine and treatment

    OpenAIRE

    Hordyjewska, Anna; Popiołek, Łukasz; Kocot, Joanna

    2014-01-01

    Copper (Cu) is an essential microelement found in all living organisms with the unique ability to adopt two different redox states—in the oxidized (Cu2+) and reduced (Cu+). It is required for survival and serves as an important catalytic cofactor in redox chemistry for proteins that carry out fundamental biological functions, important in growth and development. The deficit of copper can result in impaired energy production, abnormal glucose and cholesterol metabolism, increased oxidative dam...

  13. Copper in foods, beverages and waters from South East Spain: influencing factors and daily dietary intake by the Andalusian population.

    Science.gov (United States)

    Velasco-Reynold, C; Navarro-Alarcon, M; López-Ga De La Serrana, H; Lopez-Martinez, M C

    2008-08-01

    The copper content of 225 food, 49 beverage and twelve potable water samples were determined using atomic absorption spectrometry (AAS). Analyses of NIST and BCR reference materials demonstrated the accuracy of this technique. The highest copper levels were found in dried fruit and legumes, followed by organ meats, molluscs and crustaceans, cephalopods, cereals and sausages, respectively. In cereals, legumes and fruit, copper levels increased significantly with increasing levels of protein and decreasing carbohydrate content (p < 0.001). In meat and meat by-products, copper concentrations found in organ meats were significantly higher (p < 0.01). In fresh fish products, copper levels in shellfish were significantly higher than those measured in fish (p < 0.001). In vegetables, the copper concentrations found in mushrooms were significantly higher (p < 0.005). Mean copper concentrations analysed in cheese were statistically higher than those determined in other dairy products (p < 0.01). In beverages, copper levels determined in rum and juices were significantly higher (p < 0.001). Beverages for which a vegetable component was directly used in their manufacturing process (juices, wines and beers) had statistically higher copper levels when compared with fresh drinks. The daily dietary intake (DDI) of copper in the Andalusian diet was 1979 mug day(-1) per person. Cereals, meat, meat by-products and vegetables are the food categories that are the main source of copper in the daily diet. Taking into account the dietary reference intakes and upper levels (900 and 10, 000 mug Cu day(-1) for healthy adults, respectively), the mean copper DDI found indicate that for most of healthy adult individuals from the area, no adverse effects occur in relation to copper nutrition (deficiency or toxicity). Potable waters supplied 53 mug day(-1), which constitutes on average 0.025% of the maximum tolerable daily intake of this element set by the Joint FAO/WHO Expert Committee.

  14. The mitochondrial permeability transition, and oxidative and nitrosative stress in the mechanism of copper toxicity in cultured neurons and astrocytes.

    Science.gov (United States)

    Reddy, Pichili V B; Rao, Kakulavarapu V Rama; Norenberg, Michael D

    2008-08-01

    Copper is an essential element and an integral component of various enzymes. However, excess copper is neurotoxic and has been implicated in the pathogenesis of Wilson's disease, Alzheimer's disease, prion conditions, and other disorders. Although mechanisms of copper neurotoxicity are not fully understood, copper is known to cause oxidative stress and mitochondrial dysfunction. As oxidative stress is an important factor in the induction of the mitochondrial permeability transition (mPT), we determined whether mPT plays a role in copper-induced neural cell injury. Cultured astrocytes and neurons were treated with 20 microM copper and mPT was measured by changes in the cyclosporin A (CsA)-sensitive inner mitochondrial membrane potential (Delta Psi m), employing the potentiometric dye TMRE. In astrocytes, copper caused a 36% decrease in the Delta Psi m at 12 h, which decreased further to 48% by 24 h and remained at that level for at least 72 h. Cobalt quenching of calcein fluorescence as a measure of mPT similarly displayed a 45% decrease at 24 h. Pretreatment with antioxidants significantly blocked the copper-induced mPT by 48-75%. Copper (24 h) also caused a 30% reduction in ATP in astrocytes, which was completely blocked by CsA. Copper caused death (42%) in astrocytes by 48 h, which was reduced by antioxidants (35-60%) and CsA (41%). In contrast to astrocytes, copper did not induce mPT in neurons. Instead, it caused early and extensive death with a concomitant reduction (63%) in ATP by 14 h. Neuronal death was prevented by antioxidants and nitric oxide synthase inhibitors but not by CsA. Copper increased protein tyrosine nitration in both astrocytes and neurons. These studies indicate that mPT, and oxidative and nitrosative stress represent major factors in copper-induced toxicity in astrocytes, whereas oxidative and nitrosative stress appears to play a major role in neuronal injury.

  15. Renal cortex copper concentration in acute copper poisoning in calves

    Directory of Open Access Journals (Sweden)

    Luis E. Fazzio

    2012-01-01

    Full Text Available The aim of this study was to estimate the diagnostic value of renal cortex copper (Cu concentration in clinical cases of acute copper poisoning (ACP. A total of 97 calves that died due to subcutaneous copper administration were compiled in eleven farms. At least, one necropsy was conducted on each farm and samples for complementary analysis were taken. The degree of autolysis in each necropsy was evaluated. The cases appeared on extensive grazing calf breeding and intensive feedlot farms, in calves of 60 to 200 kg body weight. Mortality varied from 0.86 to 6.96 %, on the farms studied. The first succumbed calf was found on the farms between 6 and 72 hours after the susbcutaneous Cu administration. As discrepancies regarding the reference value arose, the local value (19.9 parts per million was used, confirming the diagnosis of acute copper poisoning in 93% of the analyzed kidney samples. These results confirm the value of analysis of the cortical kidney Cu concentration for the diagnosis of acute copper poisoning.

  16. Copper metallurgy at the crossroads

    Directory of Open Access Journals (Sweden)

    Habashi F.

    2007-01-01

    Full Text Available Copper technology changed from the vertical to the horizontal furnace and from the roast reaction to converting towards the end of the last century. However, the horizontal furnace proved to be an inefficient and polluting reactor. As a result many attempts were made to replace it. In the past 50 years new successful melting processes were introduced on an industrial scale that were more energy efficient and less polluting. In addition, smelting and converting were conducted in a single reactor in which the concentrate was fed and the raw copper was produced. The standing problem in many countries, however, is marketing 3 tonnes of sulfuric acid per tonne of copper produced as well as emitting large amounts of excess SO2 in the atmosphere. Pressure hydrometallurgy offers the possibility of liberating the copper industry from SO2 problem. Heap leaching technology has become a gigantic operation. Combined with solvent extraction and electrowinning it contributes today to about 20% of copper production and is expected to grow. Pressure leaching offers the possibility of liberating the copper industry from SO2 problem. The technology is over hundred years old. It is applied for leaching a variety of ores and concentrates. Hydrothermal oxidation of sulfide concentrates has the enormous advantage of producing elemental sulfur, hence solving the SO2 and sulfuric acid problems found in smelters. Precipitation of metals such as nickel and cobalt under hydrothermal conditions has been used for over 50 years. It has the advantage of a compact plant but the disadvantage of producing ammonium sulfate as a co-product. In case of copper, however, precipitation takes place without the need of neutralizing the acid, which is a great advantage and could be an excellent substitute for electrowinning which is energy intensive and occupies extensive space. Recent advances in the engineering aspects of pressure equipment design open the door widely for increased

  17. A pyrazolyl-based thiolato single-source precursor for the selective synthesis of isotropic copper-deficient copper(I) sulfide nanocrystals: synthesis, optical and photocatalytic activity

    Science.gov (United States)

    Mondal, Gopinath; Santra, Ananyakumari; Bera, Pradip; Acharjya, Moumita; Jana, Sumanta; Chattopadhyay, Dipankar; Mondal, Anup; Seok, Sang Il; Bera, Pulakesh

    2016-10-01

    Hexagonal copper-deficient copper(I) sulfide (Cu2- x S, x = 0.03, 0.2) nanocrystals (NCs) are synthesized from a newly prepared single-source precursor (SP), [Cu(bdpa)2][CuCl2], where bdpa is benzyl 3,5-dimethyl-pyrazole-1-carbodithioate. The SP is crystallized with space group Pī and possesses a distorted tetrahedron structure with a CuN2S2 chromophore where the central copper is in +1 oxidation state. Distortion in copper(I) structure and the low decomposition temperature of SP make it favorable for the low-temperature solvent-assisted selective growth of high-copper content sulfides. The nucleation and growth of Cu2- x S ( x = 0.03, 0.2) are effectively controlled by the SP and the solvent in the solvothermal decomposition process. During decomposition, fragment benzyl thiol (PhCH2SH) from SP effectively passivates the nucleus leading to spherical nanocrystals. Further, solvent plays an important role in the selective thermochemical transformation of CuI-complex to Cu2- x S ( x = 0.03, 0.2) NCs. The chelating binders (solvent) like ethylene diamine (EN) and ethylene glycol (EG) prefer to form spherical Cu1.97S nanoparticles (djurleite), whereas nonchelating hydrazine hydrate (HH) shows the tendency to furnish hexagonal platelets of copper-deficient Cu1.8S. The optical band gap values (2.25-2.50 eV) show quantum confinement effect in the structure. The synthesized NCs display excellent catalytic activity ( 87 %) toward photodegradation of organic dyes like Congo Red (CR) and Methylene Blue (MB).

  18. Chinese Jingdezhen blue and white imperial porcelain

    Institute of Scientific and Technical Information of China (English)

    WU; Juan; LI; Jiazhi; DENG; Zequn; WANG; Changsui

    2004-01-01

    Jingdezhen blue and white imperial porcelain specimens from the Yuan, Ming and Qing dynasties have been systematically analyzed using a nondestructive test method--?energy dispersive X-ray fluorescence analysis (EDXRF). The derived data of major and trace element compositions have been treated by correspondence analysis. The variation laws of the composition patterns for Jingdezhen blue and white imperial porcelain in different historical periods owing to the change in raw materials, recipe and technology have been discussed, and a time model related to variation of element composition has been preliminarily established, It would be helpful for scientific dating of Jingdezhen blue and white imperial porcelain, and even for the studies on the whole field of identification of ancient ceramics.

  19. Bump in the blue axion isocurvature spectrum

    Science.gov (United States)

    Chung, Daniel J. H.; Upadhye, Amol

    2017-01-01

    Blue axion isocurvature perturbations are both theoretically well motivated and interesting from a detectability perspective. These power spectra generically have a break from the blue region to a flat region. Previous investigations of the power spectra were analytic, which left a gap in the predicted spectrum in the break region due to the nonapplicability of the used analytic techniques. We therefore compute the isocurvature spectrum numerically for an explicit supersymmetric axion model. We find a bump that enhances the isocurvature signal for this class of scenarios. A fitting function of three parameters is constructed that fits the spectrum well for the particular axion model we study. This fitting function should be useful for blue isocurvature signal hunting in data and making experimental sensitivity forecasts.

  20. A Stable Blue Organic Electroluminescent Material

    Institute of Scientific and Technical Information of China (English)

    郑新友; 吴有智; 等

    2002-01-01

    In order to compare two kinds of blue electroluminescent materials,we have investigated two kinds of blue OLEDs with the similar structure ITO/CuPc/NPB/JBEM:perylene/Alq/Mg:Ag[device(J)] and ITO/CuPc/NPB/DPVBi:perylene/Alq/Mg:Ag[device(D)].The difference of luminance and efficiency was not obvious for the two devices,However,there was remarkable difference for their lifetime.The device(J) achieved longer half lifetime of 1035h at initial luminance of 100 cd/m2,and that of device(D) was only255h,According to their energy level diagrams,the differentce of their stability may originate from different host materials in the two devices.It may be attributed to the better thermal stability of JBEM molecues than that of DPVBi.It is shown that JBEM may be a promising blue organic electroluminescent material with great stability.