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Jonathan A R Worrall - One of the best experts on this subject based on the ideXlab platform.
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Copper Storage Protein From Streptomyces Lividans
'Wiley', 2021Co-Authors: Jonathan A R WorrallAbstract:The ability of copper to cycle between two redox states (CuI/CuII), each having a preference for either soft or hard ligands, gives rise to a diverse spectrum of coordinatIon spheres within protein scaffolds that results in a broad range of functIonalities. Maintaining cellular copper bioavailability and preventing the detrimental effects associated with excess CuI is critical for cell viability. In the bacterial cytosol, regulatory systems exist that are chemically tuned to constrain and regulate Cuprous Ion bioavailability through high-affinity-binding sites that use predominately Cuprous-thiolate coordinatIon chemistry. Recently, a family of four-helix bundle proteins with a cysteine-rich core has been discovered to reside in the bacterial cytosol. These proteins have been named copper storage proteins (Csps), reflecting their ability to coordinate up to 20 Cuprous Ions in the cysteine-rich core. In the Gram-positive, filamentous bacterium, Streptomyces lividans, a Csp is present. The copper regulatory systems in S. lividans have been well studied and the extracytoplasmic copper-trafficking pathways, essential to initiate the copper-dependent morphological differentiatIon, identified. The role the Csp plays in the copper biochemistry of S. lividans has been investigated from both a biological and bioinorganic chemistry perspective, and the current understanding is summarized
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a histidine residue and a tetranuclear Cuprous thiolate cluster dominate the copper loading landscape of a copper storage protein from streptomyces lividans
Chemistry: A European Journal, 2019Co-Authors: M L Straw, Michael T Wilson, Jonathan A R WorrallAbstract:The chemical basis for protecting organisms against the toxic effect imposed by excess Cuprous Ions is to constrain this through high-affinity binding sites that use Cuprous-thiolate coordinatIon chemistry. In bacteria, a family of cysteine rich four-helix bundle proteins utilise thiolate chemistry to bind up to 80 Cuprous Ions. These proteins have been termed copper storage proteins (Csp). The present study investigates Cuprous Ion loading to the Csp from Streptomyces lividans (SlCsp) using a combinatIon of X-ray crystallography, site-directed mutagenesis and stopped-flow reactIon kinetics with either aquatic Cuprous Ions or a chelating donor. We illustrate that at low Cuprous Ion concentratIons, copper is loaded exclusively into an outer core regIon of SlCsp via one end of the four-helix bundle, facilitated by a set of three histidine residues. X-ray crystallography reveals the existence of polynuclear Cuprous-thiolate clusters culminating in the assembly of a tetranuclear [Cu4 (μ2 -S-Cys)4 (Νδ1 -His)] cluster in the outer core. As more Cuprous Ions are loaded, the cysteine lined inner core of SlCsp fills with Cuprous Ions but in a fluxIonal and dynamic manner with no evidence for the assembly of further intermediate polynuclear Cuprous-thiolate clusters as observed in the outer core. Using site-directed mutagenesis a key role for His107 in the efficient loading of Cuprous Ions from a donor is established. A model of copper loading to SlCsp is proposed and discussed.
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A histidine residue and a tetranuclear Cuprous‐thiolate cluster dominate the copper loading landscape of a copper storage protein from Streptomyces lividans
'Wiley', 2019Co-Authors: Straw, Megan L, Hough, Michael A, Wilson, Michael T, Jonathan A R WorrallAbstract:The chemical basis for protecting organisms against the toxic effect imposed by excess Cuprous Ions is to constrain this through high‐affinity binding sites that use Cuprous‐thiolate coordinatIon chemistry. In bacteria, a family of cysteine rich four‐helix bundle proteins utilise thiolate chemistry to bind up to 80 Cuprous Ions. These proteins have been termed copper storage proteins (Csp). The present study investigates Cuprous Ion loading to the Csp from Streptomyces lividans (SlCsp) using a combinatIon of X‐ray crystallography, site‐directed mutagenesis and stopped‐flow reactIon kinetics with either aquatic Cuprous Ions or a chelating donor. We illustrate that at low Cuprous Ion concentratIons, copper is loaded exclusively into an outer core regIon of SlCsp via one end of the four‐helix bundle, facilitated by a set of three histidine residues. X‐ray crystallography reveals the existence of polynuclear Cuprous‐thiolate clusters culminating in the assembly of a tetranuclear [Cu4(μ2‐S‐Cys)4(Νδ1‐His)] cluster in the outer core. As more Cuprous Ions are loaded, the cysteine lined inner core of SlCsp fills with Cuprous Ions but in a fluxIonal and dynamic manner with no evidence for the assembly of further intermediate polynuclear Cuprous‐thiolate clusters as observed in the outer core. Using site‐directed mutagenesis a key role for His107 in the efficient loading of Cuprous Ions from a donor is established. A model of copper loading to SlCsp is proposed and discussed
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a cytosolic copper storage protein provides a second level of copper tolerance in streptomyces lividans
Metallomics, 2018Co-Authors: M L Straw, Michael A Hough, Erik Vijgenboom, Michael T Wilson, Amanda K Chaplin, Jordi Paps, Vassiliy N Bavro, Jonathan A R WorrallAbstract:Streptomyces lividans has a distinct dependence on the bioavailability of copper for its morphological development. A cytosolic copper resistance system is operative in S. lividans that serves to preclude deleterious copper levels. This system comprises of several CopZ-like copper chaperones and P1-type ATPases, predominantly under the transcriptIonal control of a metalloregulator from the copper sensitive operon repressor (CsoR) family. In the present study, we discover a new layer of cytosolic copper resistance in S. lividans that involves a protein belonging to the newly discovered family of copper storage proteins, which we have named Ccsp (cytosolic copper storage protein). From an evolutIonary perspective, we find Ccsp homologues to be widespread in Bacteria and extend through into Archaea and Eukaryota. Under copper stress Ccsp is upregulated and consists of a homotetramer assembly capable of binding up to 80 Cuprous Ions (20 per protomer). X-ray crystallography reveals 18 cysteines, 3 histidines and 1 aspartate are involved in Cuprous Ion coordinatIon. Loading of Cuprous Ions to Ccsp is a cooperative process with a Hill coefficient of 1.9 and a CopZ-like copper chaperone can transfer copper to Ccsp. A Δccsp mutant strain indicates that Ccsp is not required under initial copper stress in S. lividans, but as the CsoR/CopZ/ATPase efflux system becomes saturated, Ccsp facilitates a second level of copper tolerance.
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structural and mechanistic insights into an extracytoplasmic copper trafficking pathway in streptomyces lividans
Biochemical Journal, 2014Co-Authors: Katie L I M Blundell, Michael A Hough, Erik Vijgenboom, Jonathan A R WorrallAbstract:In Streptomyces lividans an extracytoplasmic copper-binding Sco protein plays a role in two unlinked processes: (i) initiating a morphological development switch and (ii) facilitating the co-factoring of the CuA domain of CcO (cytochrome c oxidase). How Sco obtains copper once secreted to the extracytoplasmic environment is unknown. In the present paper we report on a protein possessing an HX₆MX₂₁HXM motif that binds a single Cuprous Ion with subfemtomolar affinity. High-resolutIon X-ray structures of this extracytoplasmic copper chaperone-like protein (ECuC) in the apo- and Cu(I)-bound states reveal that the latter possesses a surface-accessible Cuprous-Ion-binding site located in a dish-shaped regIon of β-sheet structure. A Cuprous Ion is transferred under a favourable thermodynamic gradient from ECuC to Sco with no back transfer occurring. The IonizatIon properties of the cysteine residues in the Cys⁸⁶xxxCys⁹⁰ copper-binding motif of Sco, together with their positIonal locatIons identified from an X-ray structure of Sco, suggests a role for Cys⁸⁶ in initiating an inter-complex ligand-exchange reactIon with Cu(I)-ECuC. GeneratIon of the genetic knockouts, Δsco, Δecuc and Δsco/ecuc, and subsequent in vivo assays lend support to the existence of a branched extracytoplasmic copper-trafficking pathway in S. lividans. One branch requires both Sco and to a certain extent ECuC to cofactor the CuA domain, whereas the other uses only Sco to deliver copper to a cuproenzyme to initiate morphological development.
David Dreisinger - One of the best experts on this subject based on the ideXlab platform.
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thermodynamics and kinetics study of tellurium removal with Cuprous Ion
Hydrometallurgy, 2014Co-Authors: Mohammad Mokmeli, David Dreisinger, Berend WassinkAbstract:Abstract The chemistry and kinetics of the removal of tellurium from copper sulphate-sulphuric acid solutIon by Cuprous Ion reductIon and precipitatIon were studied. The TeVI reductIon reactIon order with respect to Cuprous and tellurium concentratIon was investigated at an acidity range of 10–100 g/L H2SO4 and at temperatures of 75 °C–95 °C. The reductIon reactIon mechanism, a suggested rate determining step and a rate law were offered accordingly for reductIon of TeVI with Cuprous. The kinetics fit the simple rate equatIon of − dT e VI dt = k 1 C u + T e VI . A plausible TeVI reductIon with Cuprous was suggested via slow reductIon of H6TeO6 to TeO(OH)+ followed by faster reductIon of TeO(OH)+ to lower tellurium oxidatIon states. The rate constant k1 was calculated at different sulphuric acid concentratIons (10, 15, 50, 75, 100 g/L) at T = 95.2 °C. Increasing solutIon acidity significantly increased the tellurium reductIon reactIon rate. An empirical correlatIon of k1 = 0.0297 × [H2SO4]1.35 was found between the rate constants and the sulphuric acid concentratIon over the range of 10 g/L
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kinetics study of selenium removal from copper sulfate sulfuric acid solutIon
Hydrometallurgy, 2013Co-Authors: Mohammad Mokmeli, Berend Wassink, David DreisingerAbstract:Abstract The chemistry and kinetics of the removal of selenium from copper sulfate–sulfuric acid solutIon by Cuprous Ion reductIon and precipitatIon were studied. Continuous measurement of [Cu+] was carried out by potentiometric monitoring. The stoichiometry of the overall reactIon was found to be: HSeO4− + 9.96 Cu+ aq + 7H+ = Cu1.98Se + 4H2O + 7.98Cu+ 2 at 95.1 °C. The reactIon mechanism appears to be based on an initial one electron transfer to form intermediate Se(V). The kinetics fit the rate law: − d Se VI dt = k 1 Cu + 2 Se VI k − 1 k 2 Cu + 2 + Cu + at constant acidity. The values of k1 and k− 1/k2 were 0.0055 M− 1 s− 1 and 1.5 × 10− 4 at [H2SO4] = 100 g/L, [Cu+ 2] = 50 g/L at 95.1 °C. Rate constants are almost independent of cupric concentratIon at constant Ionic strength but decrease slightly with increasing cupric concentratIon and increasing Ionic strength. ActivatIon energy of 85.5 kJ/mol for k1 was calculated by varying the temperature from 86.1 to 98.6 °C. Cuprous selenide precipitates react with cupric Ion and generate Cuprous Ion and non-stoichiometric CuxSe precipitate (1.88
M L Straw - One of the best experts on this subject based on the ideXlab platform.
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a histidine residue and a tetranuclear Cuprous thiolate cluster dominate the copper loading landscape of a copper storage protein from streptomyces lividans
Chemistry: A European Journal, 2019Co-Authors: M L Straw, Michael T Wilson, Jonathan A R WorrallAbstract:The chemical basis for protecting organisms against the toxic effect imposed by excess Cuprous Ions is to constrain this through high-affinity binding sites that use Cuprous-thiolate coordinatIon chemistry. In bacteria, a family of cysteine rich four-helix bundle proteins utilise thiolate chemistry to bind up to 80 Cuprous Ions. These proteins have been termed copper storage proteins (Csp). The present study investigates Cuprous Ion loading to the Csp from Streptomyces lividans (SlCsp) using a combinatIon of X-ray crystallography, site-directed mutagenesis and stopped-flow reactIon kinetics with either aquatic Cuprous Ions or a chelating donor. We illustrate that at low Cuprous Ion concentratIons, copper is loaded exclusively into an outer core regIon of SlCsp via one end of the four-helix bundle, facilitated by a set of three histidine residues. X-ray crystallography reveals the existence of polynuclear Cuprous-thiolate clusters culminating in the assembly of a tetranuclear [Cu4 (μ2 -S-Cys)4 (Νδ1 -His)] cluster in the outer core. As more Cuprous Ions are loaded, the cysteine lined inner core of SlCsp fills with Cuprous Ions but in a fluxIonal and dynamic manner with no evidence for the assembly of further intermediate polynuclear Cuprous-thiolate clusters as observed in the outer core. Using site-directed mutagenesis a key role for His107 in the efficient loading of Cuprous Ions from a donor is established. A model of copper loading to SlCsp is proposed and discussed.
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a cytosolic copper storage protein provides a second level of copper tolerance in streptomyces lividans
Metallomics, 2018Co-Authors: M L Straw, Michael A Hough, Erik Vijgenboom, Michael T Wilson, Amanda K Chaplin, Jordi Paps, Vassiliy N Bavro, Jonathan A R WorrallAbstract:Streptomyces lividans has a distinct dependence on the bioavailability of copper for its morphological development. A cytosolic copper resistance system is operative in S. lividans that serves to preclude deleterious copper levels. This system comprises of several CopZ-like copper chaperones and P1-type ATPases, predominantly under the transcriptIonal control of a metalloregulator from the copper sensitive operon repressor (CsoR) family. In the present study, we discover a new layer of cytosolic copper resistance in S. lividans that involves a protein belonging to the newly discovered family of copper storage proteins, which we have named Ccsp (cytosolic copper storage protein). From an evolutIonary perspective, we find Ccsp homologues to be widespread in Bacteria and extend through into Archaea and Eukaryota. Under copper stress Ccsp is upregulated and consists of a homotetramer assembly capable of binding up to 80 Cuprous Ions (20 per protomer). X-ray crystallography reveals 18 cysteines, 3 histidines and 1 aspartate are involved in Cuprous Ion coordinatIon. Loading of Cuprous Ions to Ccsp is a cooperative process with a Hill coefficient of 1.9 and a CopZ-like copper chaperone can transfer copper to Ccsp. A Δccsp mutant strain indicates that Ccsp is not required under initial copper stress in S. lividans, but as the CsoR/CopZ/ATPase efflux system becomes saturated, Ccsp facilitates a second level of copper tolerance.
Mohammad Mokmeli - One of the best experts on this subject based on the ideXlab platform.
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thermodynamics and kinetics study of tellurium removal with Cuprous Ion
Hydrometallurgy, 2014Co-Authors: Mohammad Mokmeli, David Dreisinger, Berend WassinkAbstract:Abstract The chemistry and kinetics of the removal of tellurium from copper sulphate-sulphuric acid solutIon by Cuprous Ion reductIon and precipitatIon were studied. The TeVI reductIon reactIon order with respect to Cuprous and tellurium concentratIon was investigated at an acidity range of 10–100 g/L H2SO4 and at temperatures of 75 °C–95 °C. The reductIon reactIon mechanism, a suggested rate determining step and a rate law were offered accordingly for reductIon of TeVI with Cuprous. The kinetics fit the simple rate equatIon of − dT e VI dt = k 1 C u + T e VI . A plausible TeVI reductIon with Cuprous was suggested via slow reductIon of H6TeO6 to TeO(OH)+ followed by faster reductIon of TeO(OH)+ to lower tellurium oxidatIon states. The rate constant k1 was calculated at different sulphuric acid concentratIons (10, 15, 50, 75, 100 g/L) at T = 95.2 °C. Increasing solutIon acidity significantly increased the tellurium reductIon reactIon rate. An empirical correlatIon of k1 = 0.0297 × [H2SO4]1.35 was found between the rate constants and the sulphuric acid concentratIon over the range of 10 g/L
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kinetics study of selenium removal from copper sulfate sulfuric acid solutIon
Hydrometallurgy, 2013Co-Authors: Mohammad Mokmeli, Berend Wassink, David DreisingerAbstract:Abstract The chemistry and kinetics of the removal of selenium from copper sulfate–sulfuric acid solutIon by Cuprous Ion reductIon and precipitatIon were studied. Continuous measurement of [Cu+] was carried out by potentiometric monitoring. The stoichiometry of the overall reactIon was found to be: HSeO4− + 9.96 Cu+ aq + 7H+ = Cu1.98Se + 4H2O + 7.98Cu+ 2 at 95.1 °C. The reactIon mechanism appears to be based on an initial one electron transfer to form intermediate Se(V). The kinetics fit the rate law: − d Se VI dt = k 1 Cu + 2 Se VI k − 1 k 2 Cu + 2 + Cu + at constant acidity. The values of k1 and k− 1/k2 were 0.0055 M− 1 s− 1 and 1.5 × 10− 4 at [H2SO4] = 100 g/L, [Cu+ 2] = 50 g/L at 95.1 °C. Rate constants are almost independent of cupric concentratIon at constant Ionic strength but decrease slightly with increasing cupric concentratIon and increasing Ionic strength. ActivatIon energy of 85.5 kJ/mol for k1 was calculated by varying the temperature from 86.1 to 98.6 °C. Cuprous selenide precipitates react with cupric Ion and generate Cuprous Ion and non-stoichiometric CuxSe precipitate (1.88
Michael T Wilson - One of the best experts on this subject based on the ideXlab platform.
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a histidine residue and a tetranuclear Cuprous thiolate cluster dominate the copper loading landscape of a copper storage protein from streptomyces lividans
Chemistry: A European Journal, 2019Co-Authors: M L Straw, Michael T Wilson, Jonathan A R WorrallAbstract:The chemical basis for protecting organisms against the toxic effect imposed by excess Cuprous Ions is to constrain this through high-affinity binding sites that use Cuprous-thiolate coordinatIon chemistry. In bacteria, a family of cysteine rich four-helix bundle proteins utilise thiolate chemistry to bind up to 80 Cuprous Ions. These proteins have been termed copper storage proteins (Csp). The present study investigates Cuprous Ion loading to the Csp from Streptomyces lividans (SlCsp) using a combinatIon of X-ray crystallography, site-directed mutagenesis and stopped-flow reactIon kinetics with either aquatic Cuprous Ions or a chelating donor. We illustrate that at low Cuprous Ion concentratIons, copper is loaded exclusively into an outer core regIon of SlCsp via one end of the four-helix bundle, facilitated by a set of three histidine residues. X-ray crystallography reveals the existence of polynuclear Cuprous-thiolate clusters culminating in the assembly of a tetranuclear [Cu4 (μ2 -S-Cys)4 (Νδ1 -His)] cluster in the outer core. As more Cuprous Ions are loaded, the cysteine lined inner core of SlCsp fills with Cuprous Ions but in a fluxIonal and dynamic manner with no evidence for the assembly of further intermediate polynuclear Cuprous-thiolate clusters as observed in the outer core. Using site-directed mutagenesis a key role for His107 in the efficient loading of Cuprous Ions from a donor is established. A model of copper loading to SlCsp is proposed and discussed.
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a cytosolic copper storage protein provides a second level of copper tolerance in streptomyces lividans
Metallomics, 2018Co-Authors: M L Straw, Michael A Hough, Erik Vijgenboom, Michael T Wilson, Amanda K Chaplin, Jordi Paps, Vassiliy N Bavro, Jonathan A R WorrallAbstract:Streptomyces lividans has a distinct dependence on the bioavailability of copper for its morphological development. A cytosolic copper resistance system is operative in S. lividans that serves to preclude deleterious copper levels. This system comprises of several CopZ-like copper chaperones and P1-type ATPases, predominantly under the transcriptIonal control of a metalloregulator from the copper sensitive operon repressor (CsoR) family. In the present study, we discover a new layer of cytosolic copper resistance in S. lividans that involves a protein belonging to the newly discovered family of copper storage proteins, which we have named Ccsp (cytosolic copper storage protein). From an evolutIonary perspective, we find Ccsp homologues to be widespread in Bacteria and extend through into Archaea and Eukaryota. Under copper stress Ccsp is upregulated and consists of a homotetramer assembly capable of binding up to 80 Cuprous Ions (20 per protomer). X-ray crystallography reveals 18 cysteines, 3 histidines and 1 aspartate are involved in Cuprous Ion coordinatIon. Loading of Cuprous Ions to Ccsp is a cooperative process with a Hill coefficient of 1.9 and a CopZ-like copper chaperone can transfer copper to Ccsp. A Δccsp mutant strain indicates that Ccsp is not required under initial copper stress in S. lividans, but as the CsoR/CopZ/ATPase efflux system becomes saturated, Ccsp facilitates a second level of copper tolerance.
