314 results on '"ABERGEL, A."'
Search Results
2. Infrared Photon Pair-Production in Ligand-Sensitized Lanthanide Nanocrystals
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Peter Agbo, Jacob S. Kanady, and Rebecca J. Abergel
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sensitization ,lanthanide ,two-photon ,downconversion ,energy transfer ,Chemistry ,QD1-999 - Abstract
This report details spectroscopic characterizations of rare-earth, core-shell nanoparticles decorated with the f-element chelator 3,4,3-LI(1,2-HOPO). Evidence of photon downconversion is corroborated through detailed power dependence measurements, which suggest two-photon decay paths are active in these materials, albeit only representing a minority contribution of the sum luminescence, with emission being dominated by normal, Stokes' shifted fluorescence. Specifically, ultraviolet ligand photosensitization of Nd3+ ions in a NaGdF4 host shell results in energy transfer to a Nd3+/Yb3+-doped NaGdF4 nanoparticle core. The population and subsequent decay of core, Yb3+2F5/2 states result in a spectral shift of 620 nm, manifested in a NIR emission displaying luminescence profiles diagnostic of Yb3+ and Nd3+ excited state decays. Emphasis is placed on the generality of this material architecture for realizing ligand-pumped, multi-photon downconversion, with the Nd3+/Yb3+ system presented here functioning as a working prototype for a design principle that may be readily extended to other lanthanide pairs.
- Published
- 2020
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3. Structural and spectroscopic characterization of an einsteinium complex
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Katherine M. Shield, Stosh A. Kozimor, Jennifer N. Wacker, Rebecca J. Abergel, Kurt F. Smith, Leticia Arnedo-Sanchez, Liane M. Moreau, Tracy M. Mattox, Corwin H. Booth, Karah E. Knope, Zachary R. Jones, and Korey P. Carter
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Lanthanide ,chemistry.chemical_classification ,Multidisciplinary ,010405 organic chemistry ,chemistry.chemical_element ,Actinide ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Coordination complex ,chemistry ,Group (periodic table) ,Chemical physics ,Total angular momentum quantum number ,Einsteinium ,Atomic number ,Spin (physics) - Abstract
The transplutonium elements (atomic numbers 95-103) are a group of metals that lie at the edge of the periodic table. As a result, the patterns and trends used to predict and control the physics and chemistry for transition metals, main-group elements and lanthanides are less applicable to transplutonium elements. Furthermore, understanding the properties of these heavy elements has been restricted by their scarcity and radioactivity. This is especially true for einsteinium (Es), the heaviest element on the periodic table that can currently be generated in quantities sufficient to enable classical macroscale studies1. Here we characterize a coordination complex of einsteinium, using less than 200 nanograms of 254Es (with half-life of 275.7(5) days), with an organic hydroxypyridinone-based chelating ligand. X-ray absorption spectroscopic and structural studies are used to determine the energy of the L3-edge and a bond distance of einsteinium. Photophysical measurements show antenna sensitization of EsIII luminescence; they also reveal a hypsochromic shift on metal complexation, which had not previously been observed in lower-atomic-number actinide elements. These findings are indicative of an intermediate spin-orbit coupling scheme in which j-j coupling (whereby single-electron orbital angular momentum and spin are first coupled to form a total angular momentum, j) prevails over Russell-Saunders coupling. Together with previous actinide complexation studies2, our results highlight the need to continue studying the unusual behaviour of the actinide elements, especially those that are scarce and short-lived.
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- 2021
4. Efficient discrimination of transplutonium actinides by in vivo models
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Stacey Gauny, Gauthier J.-P. Deblonde, Roger M. Pallares, Erin Jarvis, Rebecca J. Abergel, Birgitta Kullgren, and Dahlia D. An
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Biodistribution ,In vivo ,Chemistry ,Small animal ,Radiochemistry ,Homogeneous group ,Chelation ,General Chemistry ,Actinide - Abstract
Transplutonium actinides are among the heaviest elements whose macroscale chemical properties can be experimentally tested. Being scarce and hazardous, their chemistry is rather unexplored, and they have traditionally been considered a rather homogeneous group, with most of their characteristics extrapolated from lanthanide surrogates. Newly emerged applications for these elements, combined with their persistent presence in nuclear waste, however, call for a better understanding of their behavior in complex living systems. In this work, we explored the biodistribution and excretion profiles of four transplutonium actinides (248Cm, 249Bk, 249Cf and 253Es) in a small animal model, and evaluated their in vivo sequestration and decorporation by two therapeutic chelators, diethylenetriamine pentaacetic acid and 3,4,3-LI(1,2-HOPO). Notably, the organ deposition patterns of those transplutonium actinides were element-dependent, particularly in the liver and skeleton, where lower atomic number radionuclides showed up to 7-fold larger liver/skeleton accumulation ratios. Nevertheless, the metal content in multiple organs was significantly decreased for all tested actinides, particularly in the liver, after administering the therapeutic agent 3,4,3-LI(1,2-HOPO) post-contamination. Lastly, the systematic comparison of the radionuclide biodistributions showed discernibly element-dependent organ depositions, which may provide insights into design rules for new bio-inspired chelating systems with high sequestration and separation performance.
- Published
- 2021
5. Chelator-assisted high performance liquid chromatographic separation of trivalent lanthanides and actinides
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Roger M. Pallares, Rebecca J. Abergel, Solène Hébert, and Manuel Sturzbecher-Hoehne
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Lanthanide ,Chromatographic separation ,Chelating ligands ,Adsorption ,Chemistry ,Inorganic chemistry ,Materials Chemistry ,Chelation ,Recovery techniques ,Economic shortage ,General Chemistry ,Actinide ,Catalysis - Abstract
While lanthanides and actinides are essential to many clean energy technologies, they are at high risk for supply chain disruption. As such, the development of recycling and recovery techniques for lanthanides and actinides is essential to avoid future shortages. Conventional reversed-phase chromatography cannot readily discriminate between the metals, making column modifications, such as adsorption of ion-pair agents, necessary to achieve element separation. In this work, we demonstrate that a siderophore-inspired synthetic derivative, 3,4,3-LI(1,2-HOPO), can be used as an in situ chelating agent, promoting lanthanide and trivalent actinide separation in less than 15 min without column modification. By employing alternative chelating ligands, f-element separations are therefore achievable in chromatographic systems used in analytical laboratories around the world, creating new opportunities for the separation and recovery of these critical materials.
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- 2021
6. ThIV–Desferrioxamine: characterization of a fluorescent bacterial probe
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Mila Nhu Lam, Maksim Y. Livshits, Kelly E. Aldrich, Stosh A. Kozimor, Laura M. Lilley, Loreen R. Stromberg, Benjamin W. Stein, Rebecca J. Abergel, Gregory L. Wagner, Harshini Mukundan, and Michael T. Janicke
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Inorganic Chemistry ,Siderophore ,chemistry.chemical_compound ,Fluorophore ,chemistry ,Fluorescence microscope ,Biophysics ,Chelation ,Nuclear magnetic resonance spectroscopy ,Fluorescence ,Conjugate - Abstract
Diversifying our ability to guard against emerging pathogenic threats is essential for keeping pace with global health challenges, including those presented by drug-resistant bacteria. Some modern diagnostic and therapeutic innovations to address this challenge focus on targeting methods that exploit bacterial nutrient sequestration pathways, such as the desferrioxamine (DFO) siderophore used by Staphylococcus aureus (S. aureus) to sequester FeIII. Building on recent studies that have shown DFO to be a versatile vehicle for chemical delivery, we show proof-of-principle that the FeIII sequestration pathway can be used to deliver a potential radiotherapeutic. Our approach replaces the FeIII nutrient sequestered by H4DFO+ with ThIV and made use of a common fluorophore, FITC, which we covalently bonded to DFO to provide a combinatorial probe for simultaneous chelation paired with imaging and spectroscopy, H3DFO_FITC. Combining insight provided from FITC-based imaging with characterization by NMR spectroscopy, we demonstrated that the fluorescent DFO_FITC conjugate retained the ThIV chelation properties of native H4DFO+. Fluorescence microscopy with both [Th(DFO_FITC)] and [Fe(DFO_FITC)] complexes showed similar uptake by S. aureus and increased intercellular accumulation as compared to the FITC and unchelated H3DFO_FITC controls. Collectively, these results demonstrate the potential for the newly developed H3DFO_FITC conjugate to be used as a targeting vector and bacterial imaging probe for S. aureus. The results presented within provide a framework to expand H4DFO+ and H3DFO_FITC to relevant radiotherapeutics (like 227Th).
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- 2021
7. Rational Design of a Uranyl Metal–Organic Framework for the Capture and Colorimetric Detection of Organic Dyes
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Trevor D. Lohrey, Dallas D. Reilly, Mark Kalaj, Robert G. Surbella, Bruce K. McNamara, Korey P. Carter, Jon M. Schwantes, and Rebecca J. Abergel
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Thermogravimetric analysis ,Photoluminescence ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,General Chemistry ,010402 general chemistry ,Uranyl ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Absorbance ,chemistry.chemical_compound ,Physical chemistry ,Thermal stability ,Metal-organic framework ,Luminescence ,Single crystal - Abstract
A new uranyl containing metal-organic framework, RPL-1: [(UO2)2(C28H18O8)] . H2O (RPL for Radiochemical Processing Laboratory), was prepared, structurally characterized, and the solid-state photoluminescence properties explored. Single crystal X-ray diffraction data reveals the structure of RPL-1 consists of two crystallographically unique three dimensional, interpenetrating nets with a 4,3-connected tbo topology. Each net contains large pores with an average width of 22.8 A and is formed from monomeric, hexagonal bipyramidal uranyl nodes that are linked via 1,2,4,5-tetrakis(4-carboxyphenyl)benzene (TCPB) ligands. The thermal and photophysical properties of RPL-1 were investigated using thermogravimetric analysis and absorbance, fluorescence, and lifetime spectroscopies. The material displays excellent thermal stability and temperature dependent uranyl and TCPB luminescence. The framework is stable in aqueous media and due to the large void space (constituting 76 % of the unit cell by volume) can sequester organic dyes, the uptake of which induces a visible change to the color of the material.
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- 2020
8. Characterizing the general chelating affinity of serum protein fetuin for lanthanides
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Roger M. Pallares, Manuel Sturzbecher-Hoehne, Rebecca J. Abergel, Marie-Claire Illy, and Nagender Reddy Panyala
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010405 organic chemistry ,Chemistry ,Metal ions in aqueous solution ,Inorganic chemistry ,chemistry.chemical_element ,Terbium ,010402 general chemistry ,Uranyl ,01 natural sciences ,Biochemistry ,Fetuin ,0104 chemical sciences ,Inorganic Chemistry ,Samarium ,chemistry.chemical_compound ,Chelation ,Titration ,Europium - Abstract
Fetuin is an abundant blood protein that participates in multiple biological processes, including the transport and regulation of calcium. Fetuin is also known to have a high affinity for uranium (as the uranyl dioxo cation) and plutonium, thus it has been suggested as one of the main endogenous chelating biomolecules involved in the transport of actinides following an internal uptake event. Nevertheless, no direct measurements of its affinity for f-elements beside these two actinides have been reported. Here, we investigate the interaction between fetuin and trivalent lanthanides, such as samarium, europium, terbium, and dysprosium, by mass spectrometry and fluorescence spectroscopy. Mass spectrometry results indicated that fetuin has four metal binding sites for the metal ions studied. Upon formation, the metal-protein complexes showed luminescence emission as a result of antenna sensitization of the metal ions, whose photophysics were characterized and exploited to perform direct spectrofluorimetric titrations. Furthermore, the thermodynamic constants were calculated for all complexes, confirming the formation of stable complexes with log [Formula: see text] values between 26 and 27. In characterizing the affinity of the serum protein fetuin for several f-elements, this study expands upon the initial findings focused on uranyl and plutonium, and contributes to a better understanding of the internal distribution and deposition of lanthanides, potentially representative of trivalent actinides.
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- 2020
9. Engineering Mesoporous Silica Nanoparticles for Targeted Alpha Therapy against Breast Cancer
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Steven E. Zeltmann, Dahlia D. An, Andrew M. Minor, Roger M. Pallares, Rebecca J. Abergel, Xin Liu, Stacey Gauny, and Peter Agbo
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Actinium ,Materials science ,Cell Survival ,Pyridones ,Surface Properties ,Alpha (ethology) ,Antineoplastic Agents ,Breast Neoplasms ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Heterocyclic Compounds, 1-Ring ,Breast cancer ,In vivo ,Cell Line, Tumor ,medicine ,Humans ,Cytotoxic T cell ,General Materials Science ,Particle Size ,chemistry.chemical_classification ,Molecular Structure ,Optical Imaging ,Transferrin ,Cancer ,Mesoporous silica ,Silicon Dioxide ,021001 nanoscience & nanotechnology ,medicine.disease ,0104 chemical sciences ,chemistry ,Drug delivery ,Cancer research ,Nanoparticles ,Female ,Drug Screening Assays, Antitumor ,0210 nano-technology ,Porosity - Abstract
Targeted alpha therapy, where highly cytotoxic doses are delivered to tumor cells while sparing surrounding healthy tissue, has emerged as a promising treatment against cancer. Radionuclide conjugation with targeting vectors and dose confinement, however, are still limiting factors for the widespread application of this therapy. In the current study, we developed multifunctional silica nanoconstructs for targeted alpha therapy that show targeting capabilities against breast cancer cells, cytotoxic responses at therapeutic dosages, and enhanced clearance. The silica nanoparticles were conjugated to transferrin, which promoted particle accumulation in cancerous cells, and 3,4,3-LI(1,2-HOPO), a chelator with high selectivity and binding affinity for f-block elements. High cytotoxic effects were observed when the nanoparticles were loaded with 225Ac, a clinically relevant radioisotope. Lastly, in vivo studies in mice showed that the administration of radionuclides with nanoparticles enhanced their excretion and minimized their deposition in bones. These results highlight the potential of multifunctional silica nanoparticles as delivery systems for targeted alpha therapy and offer insight into design rules for the development of new nanotherapeutic agents.
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- 2020
10. Two-Photon Antenna Sensitization of Curium: Evidencing Metal-Driven Effects on Absorption Cross Section in f-Element Complexes
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Anthony D'Aléo, James P. Cryan, Niranjan Shivaram, Roger M. Pallares, Rebecca J. Abergel, and Manuel Sturzbecher-Hoehne
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Lanthanide ,Materials science ,Curium ,Pyridones ,chemistry.chemical_element ,Ligands ,Two-photon absorption ,Fluorescence spectroscopy ,Enterobactin ,Electron Transport ,Catecholamines ,Europium ,Coordination Complexes ,Molecule ,General Materials Science ,Physical and Theoretical Chemistry ,Terbium ,Absorption (electromagnetic radiation) ,Fluorescent Dyes ,Photons ,Molecular Structure ,Absorption cross section ,Fluorescence ,Spectrometry, Fluorescence ,chemistry ,Physical chemistry ,Fluorescein - Abstract
Two-photon-excited fluorescence spectroscopy is a powerful tool to study the structural and electronic properties of optically active complexes and molecules. Although numerous lanthanide complexes have been characterized by two-photon-excited fluorescence in solution, this report is the first to apply such a technique to actinide compounds. Contrasting with previous observations in lanthanides, we demonstrate that the two-photon absorption properties of the complexes significantly depend on the metal (4f vs 5f), with Cm(III) complexes showing significantly higher two-photon absorption cross sections than lanthanide analogues and up to 200-fold stronger emission intensities. These results are consistent with electronic and structural differences between the lanthanide and actinide systems studied. Hence, the described methodology can provide valuable insights into the interactions between f-elements and ligands, along with promising prospects on the characterization of scarce compounds.
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- 2020
11. Innovative f-Element Chelating Strategies
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Rebecca J. Abergel and Stosh A. Kozimor
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Inorganic Chemistry ,Chemistry ,Chelation ,Physical and Theoretical Chemistry ,Combinatorial chemistry - Published
- 2020
12. Transforming lanthanide and actinide chemistry with nanoparticles
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Roger M. Pallares and Rebecca J. Abergel
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Lanthanide ,Actinoid Series Elements ,Actinide chemistry ,Chemistry ,Metal Nanoparticles ,Nanoparticle ,Nanotechnology ,Clinical settings ,Actinide ,Lanthanoid Series Elements ,Animals ,Humans ,General Materials Science ,Inorganic nanoparticles - Abstract
Lanthanides and actinides are used in a wide variety of applications, from energy production to life sciences. To address toxicity issues due to the chemical, and often radiological, properties of these elements, methods to quantify and recover them from industrial waste are necessary. When used in biomedicine, lanthanides and actinides are incorporated in compounds that show promising therapeutic and/or bioimaging properties, but lack robust strategies to target cancer and other pathologies. Furthermore, current decorporation protocols to respond to accidental actinide exposure rely on intravenous injections of soluble chelating agents, which are inefficient for treatment of inhaled radionuclides trapped in lungs. In recent years, nanoparticles have emerged as powerful tools in both industry and clinical settings. Because some inorganic nanoparticles are sensitive to external stimuli, such as light and magnetic fields, they can be used as building blocks for sensitive bioassays and separation techniques. In addition, nanoparticles can be functionalized with multiple ligands and act as carriers for selective delivery of therapeutic and contrast agents. This review summarizes and discusses recent progress on the use of nanoparticles in lanthanide and actinide chemistry. We examine different types of nanoparticles based on composition, functionalization, and properties, and we critically analyze their performance in a comparative mode. Our focus is two-pronged, including the nanoparticles free of lanthanides and actinides that are used for the detection, separation, or decorporation of f-block elements, as well as the nanoparticles that enhance the inherent properties of lanthanides and actinides for therapeutics, imaging and catalysis.
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- 2020
13. Expanding the Occurrence of Polysaccharides to the Viral World: The Case of Mimivirus
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Lucid Belmudes, Annalisa Salis, Chantal Abergel, Michela Tonetti, Antonio Molinaro, Anna Notaro, Gianluca Damonte, Yohann Couté, Cristina De Castro, Maria Elena Laugieri, Notaro, Anna, Couté, Yohann, Belmudes, Lucid, Laugeri, Maria Elena, Salis, Annalisa, Damonte, Gianluca, Molinaro, Antonio, Tonetti, Michela G, Abergel, Chantal, De Castro, Cristina, Information génomique et structurale (IGS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), BioSanté (UMR BioSanté), Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Université de Genève = University of Geneva (UNIGE), Université de Naples, ANR-17-EURE-0003,CBH-EUR-GS,CBH-EUR-GS(2017), European Project: 832601,Cells and giant viruses: a win-win co-evolution, Université de Genève (UNIGE), Poirot, Olivier, and VIREVOL - Cells and giant viruses: a win-win co-evolution - 832601 - INCOMING
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Glycosylation ,viruses ,Computational biology ,Biology ,Polysaccharide ,Genome ,Catalysis ,Mimiviru ,03 medical and health sciences ,chemistry.chemical_compound ,NMR spectroscopy ,Polysaccharides ,Giant Virus ,giant viruses ,Research Articles ,030304 developmental biology ,[SDV.MP.VIR] Life Sciences [q-bio]/Microbiology and Parasitology/Virology ,chemistry.chemical_classification ,0303 health sciences ,Mimivirus ,glycan ,Glycobiology ,030302 biochemistry & molecular biology ,General Medicine ,General Chemistry ,biology.organism_classification ,glycans ,glycocalyx ,Mimiviridae ,NMR ,3. Good health ,giant viruse ,chemistry ,Capsid ,Viruses ,[SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology ,Research Article - Abstract
The general perception of viruses is that they are small in terms of size and genome, and that they hijack the host machinery to glycosylate their capsid. Giant viruses subvert all these concepts: their particles are not small, and their genome is more complex than that of some bacteria. Regarding glycosylation, this concept has been already challenged by the finding that Chloroviruses have an autonomous glycosylation machinery that produces oligosaccharides similar in size to those of small viruses (6–12 units), albeit different in structure compared to the viral counterparts. We report herein that Mimivirus possesses a glycocalyx made of two different polysaccharides, now challenging the concept that all viruses coat their capsids with oligosaccharides of discrete size. This discovery contradicts the paradigm that such macromolecules are absent in viruses, blurring the boundaries between giant viruses and the cellular world and opening new avenues in the field of viral glycobiology., The giant virus Mimivirus has an icosahedral capsid embedded in a thick layer of fibrils, resembling the glycocalyx of many bacteria. This study revealed that these fibrils are composed by a limited set of carrier proteins which bear two distinct polysaccharides. The presence of polysaccharides refutes the paradigm that such macromolecules are absent in viruses and opens new avenues in the field of glycosciences and viral biology.
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- 2021
14. Multidimensional genome-wide screening in yeast provides mechanistic insights into europium toxicity
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Roger M. Pallares, David Faulkner, Jonathan A. Villalobos, Alex Loguinov, Rebecca J. Abergel, C. J. Rosen, Michael Proctor, Dahlia D. An, Kathleen A. Bjornstad, Chris D. Vulpe, and Solène Hébert
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biology ,Saccharomyces cerevisiae ,Metals and Alloys ,Biophysics ,chemistry.chemical_element ,Metal toxicity ,Computational biology ,biology.organism_classification ,Biochemistry ,Genome ,Toxicogenetics ,Yeast ,Biomaterials ,chemistry ,Europium ,Chemistry (miscellaneous) ,Genome, Fungal ,Toxicogenomics ,Gene ,Function (biology) - Abstract
Europium is a lanthanide metal that is highly valued in optoelectronics. Even though europium is used in many commercial products, its toxicological profile has only been partially characterized, with most studies focusing on identifying lethal doses in different systems or bioaccumulation in vivo. This paper describes a genome-wide toxicogenomic study of europium in Saccharomyces cerevisiae, which shares many biological functions with humans. By using a multidimensional approach and functional and network analyses, we have identified a group of genes and proteins associated with the yeast responses to ameliorate metal toxicity, which include metal discharge paths through vesicle-mediated transport, paths to regulate biologically relevant cations, and processes to reduce metal-induced stress. Furthermore, the analyses indicated that europium promotes yeast toxicity by disrupting the function of chaperones and cochaperones, which have metal-binding sites. Several of the genes and proteins highlighted in our study have human orthologues, suggesting they may participate in europium-induced toxicity in humans. By identifying the endogenous targets of europium as well as the already existing paths that can decrease its toxicity, we can determine specific genes and proteins that may help to develop future therapeutic strategies.
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- 2021
15. Assessing the onset of calcium phosphate nucleation by hyperpolarized real-time NMR
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Daniel Abergel, Dennis Kurzbach, Emmanuelle M M Weber, Thierry Azaïs, Thomas Kress, Steffi Sewsurn, Laboratoire des biomolécules (LBM UMR 7203), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM), University of Vienna [Vienna], Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Spectroscopie, Modélisation, Interfaces pour L'Environnement et la Santé (LCMCP-SMiLES), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Abergel, Daniel, Chimie Moléculaire de Paris Centre (FR 2769), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département de Chimie - ENS Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
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Calcium Phosphates ,Magnetic Resonance Spectroscopy ,Time Factors ,Chemistry ,Precipitation (chemistry) ,010401 analytical chemistry ,Nucleation ,Ionic bonding ,010402 general chemistry ,01 natural sciences ,Article ,0104 chemical sciences ,Analytical Chemistry ,law.invention ,Crystal ,law ,Chemical physics ,Phase (matter) ,[CHIM] Chemical Sciences ,[CHIM]Chemical Sciences ,Crystallization ,Polarization (electrochemistry) ,Dissolution - Abstract
International audience; We report an experimental approach for highresolution real-time monitoring of transiently formed species occurring during the onset of precipitation of ionic solids from solution. This is made possible by real-time nuclear magnetic resonance (NMR) monitoring using dissolution dynamic nuclear polarization (D-DNP) to amplify signals of functional intermediates and is supported by turbidimetry, cryo-electron microscopy and solid-state NMR measurements. D-DNP can provide drastic signal improvements in NMR signal amplitudes, permitting dramatic reductions in acquisition times and thereby enabling to probe fast interaction kinetics such as those underlying the formation of pre-nucleation species (PNS) that precede solid-liquid phase separation. This experimental strategy allows, at unprecedented detail, for investigation of the formation of calcium phosphate (CaP)-based minerals by 31 P NMR-a process of substantial industrial, geological, and biological interest. So far, many aspects of the mechanisms of CaP nucleation remain unclear due to the absence of experimental methods capable of accessing such processes on sufficiently short time scales. The approach reported here aims to address this by an improved characterization of the initial steps of CaP precipitation, permitting the detection of PNS by NMR and determination of their formation rates, exchange dynamics and sizes. Using D-DNP monitoring, we find that under our conditions i) in the first 2 seconds after preparation of oversaturated calcium phosphate solutions, PNS with a hydrodynamic radius of Rh ≈ 1 nm are formed; and ii) following this rapid initial formation, the entire crystallization processes proceed on considerably longer timescales, requiring > 20 s to form the final crystal phase.
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- 2020
16. The 4.4 Å structure of the giant Melbournevirus virion belonging to the Marseilleviridae family
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Chantal Abergel, Reddy Hkn, Martin Svenda, Kenta Okamoto, Raymond N. Burton-Smith, and Kazuyoshi Murata
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biology ,Zipper ,Capsid ,Chemistry ,Marseilleviridae ,Icosahedral symmetry ,viruses ,Biophysics ,A protein ,Giant Virus ,Trimer ,biology.organism_classification - Abstract
SummaryMembers of Marseilleviridae, one family of icosahedral giant viruses classified in 2012 have been identified worldwide in all types of environments. The virion shows a characteristic internal membrane extrusion at the five-fold vertices of the capsid, but its structural details need to be elucidated. We now report the 4.4 Å cryo-electron microscopy structure of the Melbournevirus capsid. An atomic model of the major capsid protein (MCP) shows a unique cup structure on the trimer that accommodates additional proteins. A polyalanine model of the penton base protein shows internally extended N- and C-terminals, which indirectly connect to the internal membrane extrusion. The Marseilleviruses share the same orientational organisation of the MCPs as PBCV-1 and CroV, but do not appear to possess a protein akin to the “tape measure” of these viruses. Minor capsid proteins named PC-β, zipper, and scaffold are proposed to control the dimensions of the capsid during assembly.
- Published
- 2021
17. Efficient discrimination of transplutonium actinides by
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Roger M, Pallares, Dahlia D, An, Gauthier J-P, Deblonde, Birgitta, Kullgren, Stacey S, Gauny, Erin E, Jarvis, and Rebecca J, Abergel
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Chemistry - Abstract
Transplutonium actinides are among the heaviest elements whose macroscale chemical properties can be experimentally tested. Being scarce and hazardous, their chemistry is rather unexplored, and they have traditionally been considered a rather homogeneous group, with most of their characteristics extrapolated from lanthanide surrogates. Newly emerged applications for these elements, combined with their persistent presence in nuclear waste, however, call for a better understanding of their behavior in complex living systems. In this work, we explored the biodistribution and excretion profiles of four transplutonium actinides (248Cm, 249Bk, 249Cf and 253Es) in a small animal model, and evaluated their in vivo sequestration and decorporation by two therapeutic chelators, diethylenetriamine pentaacetic acid and 3,4,3-LI(1,2-HOPO). Notably, the organ deposition patterns of those transplutonium actinides were element-dependent, particularly in the liver and skeleton, where lower atomic number radionuclides showed up to 7-fold larger liver/skeleton accumulation ratios. Nevertheless, the metal content in multiple organs was significantly decreased for all tested actinides, particularly in the liver, after administering the therapeutic agent 3,4,3-LI(1,2-HOPO) post-contamination. Lastly, the systematic comparison of the radionuclide biodistributions showed discernibly element-dependent organ depositions, which may provide insights into design rules for new bio-inspired chelating systems with high sequestration and separation performance., Transplutonium actinides are among the heaviest elements whose macroscale chemical properties can be experimentally tested.
- Published
- 2021
18. Structural properties of ultra-small thorium and uranium dioxide nanoparticles embedded in a covalent organic framework
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Corwin H. Booth, Yusen Qiao, Julian A. Rees, Daniel Olive, Yangdongling Liu, Mark D. Straub, Simon J. Teat, Dominic R. Russo, Stefan G. Minasian, Augustin Braun, David K. Shuh, Alexandre Hervé, Rebecca J. Abergel, Trevor D. Lohrey, Liane M. Moreau, Selim Alayoglu, John Arnold, and Gauthier J.-P. Deblonde
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Materials science ,Oxide ,Nanoparticle ,General Chemistry ,Grain size ,Characterization (materials science) ,Bond length ,chemistry.chemical_compound ,Chemistry ,Transition metal ,chemistry ,Chemical engineering ,Absorption (chemistry) ,Covalent organic framework - Abstract
We report the structural properties of ultra-small ThO2 and UO2 nanoparticles (NPs), which were synthesized without strong binding surface ligands by employing a covalent organic framework (COF-5) as an inert template. The resultant NPs were used to observe how structural properties are affected by decreasing grain size within bulk actinide oxides, which has implications for understanding the behavior of nuclear fuel materials. Through a comprehensive characterization strategy, we gain insight regarding how structure at the NP surface differs from the interior. Characterization using electron microscopy and small-angle X-ray scattering indicates that growth of the ThO2 and UO2 NPs was confined by the pores of the COF template, resulting in sub-3 nm particles. X-ray absorption fine structure spectroscopy results indicate that the NPs are best described as ThO2 and UO2 materials with unpassivated surfaces. The surface layers of these particles compensate for high surface energy by exhibiting a broader distribution of Th–O and U–O bond distances despite retaining average bond lengths that are characteristic of bulk ThO2 and UO2. The combined synthesis and physical characterization efforts provide a detailed picture of actinide oxide structure at the nanoscale, which remains highly underexplored compared to transition metal counterparts., ThO2 and UO2 nanoparticles synthesized using a COF-5 template exhibit unpassivated surfaces and provide insight into nanoscale properties of actinides.
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- 2021
19. Ironed Out: A Bacterial Siderophore Primer
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Rebecca J. Abergel, Andrew L. Lakes, and Julian A. Rees
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Primer (paint) ,Siderophore ,Chemistry ,engineering ,engineering.material ,Microbiology - Published
- 2019
20. Combinatorial design of multimeric chelating peptoids for selective metal coordination† †Electronic supplementary information (ESI) available: Detailed experimental procedures, LC-MS, high resolution MS, TOF-MS/MS, and NMR spectra for peptoid ligands, UV-vis and luminescence spectra for Eu and Tb peptoid and 343-LI complexes, luminescence lifetime values, example data sets from solution thermodynamic titrations, and quantum yield data are provided. See DOI: 10.1039/c9sc01068h
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Ricano, Abel, Captain, Ilya, Carter, Korey P., Nell, Bryan P., Deblonde, Gauthier J.-P., and Abergel, Rebecca J.
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Chemistry - Abstract
The combinatorial synthesis of a new library of tetrameric peptoid ligands is introduced, enabling coordination and characterization of f-block metals., Current methods for metal chelation are generally based on multidentate organic ligands, which are generated through cumbersome multistep synthetic processes that lack flexibility for systematically varying metal-binding motifs. Octadentate ligands incorporating hydroxypyridinone or catecholamide binding moieties onto a spermine scaffold are known to display some of the highest affinities towards f-elements. Enhancing binding affinity for specific lanthanide or actinide ions however, necessitates ligand architectures that allow for modular and high throughput synthesis. Here we introduce a high-throughput combinatorial library of 16 tetrameric N-substituted glycine oligomers (peptoids) containing hydroxypyridinone or catecholamide chelating units linked via an ethylenediamine bridge and, for comparison, we also synthesized the corresponding mixed ligands derived from the spermine scaffold: 3,4,3-LI(1,2-HOPO)2(CAM)2 and 3,4,3-LI(CAM)2(1,2-HOPO)2. Coordination-based luminescence studies were carried out with Eu3+ and Tb3+ to begin probing the properties of the new ligand architecture and revealed higher sensitization efficiency with the spermine scaffold as well as different spectroscopic features among the structural peptoid isomers. Solution thermodynamic properties of selected ligands revealed different coordination properties between the spermine and peptoid analogues with Eu3+ stability constants log β110 ranging from 28.88 ± 3.45 to 43.97 ± 0.49. The general synthetic strategy presented here paves the way for precision design of new specific and versatile ligands, with a variety of applications tailored towards the use of f-elements, including separations, optical device optimization, and pharmaceutical development.
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- 2019
21. Amplified luminescence in organo-curium nanocrystal hybrids
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Rebecca J. Abergel, Leticia Arnedo-Sanchez, Andrew M. Minor, Alexander Müller, Peter Agbo, and Peter Ercius
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Lanthanide ,Materials science ,Curium ,Pyridones ,chemistry.chemical_element ,Nanoparticle ,02 engineering and technology ,Actinide ,Ligands ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,Metal Chelator ,0104 chemical sciences ,chemistry ,Nanocrystal ,Excited state ,Luminescent Measurements ,Nanoparticles ,General Materials Science ,0210 nano-technology ,Luminescence ,Chelating Agents - Abstract
We present the first report of ligand-sensitized, actinide luminescence in a lanthanide nanoparticle host. Amplified luminescence of 248Cm3+ doped in a NaGdF4 lattice is achieved through optical pumping of a surface-localized metal chelator, 3,4,3-LI(1,2-HOPO), capable of sensitizing Cm3+ excited states. The data suggest the possibility of using such materials in theranostic applications, with a ligand-sensitized actinide or radio-lanthanide serving the dual roles of a nuclear decay source for radiotherapeutics, and as a luminescent center or energy transfer conduit to another emissive metal ion, for biological imaging.
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- 2019
22. Combinatorial design of multimeric chelating peptoids for selective metal coordination
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Rebecca J. Abergel, Korey P. Carter, Ilya Captain, Abel Ricano, Bryan P. Nell, and Gauthier J.-P. Deblonde
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Lanthanide ,Denticity ,010405 organic chemistry ,Ligand ,Spermine ,Ethylenediamine ,Peptoid ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Combinatorial chemistry ,Affinities ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Chelation - Abstract
Current methods for metal chelation are generally based on multidentate organic ligands, which are generated through cumbersome multistep synthetic processes that lack flexibility for systematically varying metal-binding motifs. Octadentate ligands incorporating hydroxypyridinone or catecholamide binding moieties onto a spermine scaffold are known to display some of the highest affinities towards f-elements. Enhancing binding affinity for specific lanthanide or actinide ions however, necessitates ligand architectures that allow for modular and high throughput synthesis. Here we introduce a high-throughput combinatorial library of 16 tetrameric N-substituted glycine oligomers (peptoids) containing hydroxypyridinone or catecholamide chelating units linked via an ethylenediamine bridge and, for comparison, we also synthesized the corresponding mixed ligands derived from the spermine scaffold: 3,4,3-LI(1,2-HOPO)2(CAM)2 and 3,4,3-LI(CAM)2(1,2-HOPO)2. Coordination-based luminescence studies were carried out with Eu3+ and Tb3+ to begin probing the properties of the new ligand architecture and revealed higher sensitization efficiency with the spermine scaffold as well as different spectroscopic features among the structural peptoid isomers. Solution thermodynamic properties of selected ligands revealed different coordination properties between the spermine and peptoid analogues with Eu3+ stability constants log β110 ranging from 28.88 ± 3.45 to 43.97 ± 0.49. The general synthetic strategy presented here paves the way for precision design of new specific and versatile ligands, with a variety of applications tailored towards the use of f-elements, including separations, optical device optimization, and pharmaceutical development.
- Published
- 2019
23. Melbournevirus-encoded histone doublets are recruited to virus particles and form destabilized nucleosome-like structures
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Nadège Philippe, Sandra Jeudy, Chantal Abergel, Karolin Luger, C.M. Toner, Yang Liu, Garrett B. Edwards, Alison E. White, Samuel Bowerman, and Keda Zhou
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biology ,Marseilleviridae ,viruses ,biology.organism_classification ,Virus ,Cell biology ,genomic DNA ,chemistry.chemical_compound ,Histone ,chemistry ,biology.protein ,Nucleosome ,Giant Virus ,Gene ,DNA - Abstract
SummaryThe organization of genomic DNA into defined nucleosomes has long been viewed as a hallmark of eukaryotes. This paradigm has been challenged by the identification of ‘minimalist’ histones in archaea, and more recently by the discovery of genes that encode fused remote homologs of the four eukaryotic histones inMarseilleviridae, a subfamily of giant viruses that infect amoebae. We demonstrate that viral doublet histones localize to the cytoplasmic viral factories after virus infection, and ultimately to mature virions. CryoEM structures of viral nucleosome-like particles show strong similarities to eukaryotic nucleosomes, despite the limited sequence identify. The unique connectors that link the histone chains contribute to the observed instability of viral nucleosomes, and some histone tails assume structural roles. Our results further expand the range of ‘organisms’ that have nucleosomes and suggest a specialized function of histones in the biology of these unusual viruses.One Sentence SummarySome large DNA viruses encode fused histone doublets that are targeted to viral factories and assemble into open nucleosome-like structures.
- Published
- 2021
24. Genome-wide toxicogenomic study of the lanthanides sheds light on the selective toxicity mechanisms associated with critical materials
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Solène Hébert, Alex Loguinov, C. J. Rosen, Jonathan A. Villalobos, Roger M. Pallares, Kathleen A. Bjornstad, Dahlia D. An, David Faulkner, Rebecca J. Abergel, Chris D. Vulpe, and Michael Proctor
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0301 basic medicine ,Endosome ,Toxicological Phenomena ,Saccharomyces cerevisiae ,Computational biology ,Endocytosis ,Lanthanoid Series Elements ,Toxicogenetics ,01 natural sciences ,Genome ,03 medical and health sciences ,Genetics ,Humans ,lanthanides ,Gene ,Multidisciplinary ,biology ,010405 organic chemistry ,Chemistry ,Biological Sciences ,biology.organism_classification ,Yeast ,Biosynthetic Pathways ,0104 chemical sciences ,Fungal ,030104 developmental biology ,endosomes ,toxicogenomics ,Toxicity ,Generic health relevance ,Genome, Fungal ,Toxicogenomics - Abstract
Lanthanides are a series of critical elements widely used in multiple industries, such as optoelectronics and healthcare. Although initially considered to be of low toxicity, concerns have emerged during the last few decades over their impact on human health. The toxicological profile of these metals, however, has been incompletely characterized, with most studies to date solely focusing on one or two elements within the group. In the current study, we assessed potential toxicity mechanisms in the lanthanide series using a functional toxicogenomics approach in baker’s yeast, which shares many cellular pathways and functions with humans. We screened the homozygous deletion pool of 4,291 Saccharomyces cerevisiae strains with the lanthanides and identified both common and unique functional effects of these metals. Three very different trends were observed within the lanthanide series, where deletions of certain proteins on membranes and organelles had no effect on the cellular response to early lanthanides while inducing yeast sensitivity and resistance to middle and late lanthanides, respectively. Vesicle-mediated transport (primarily endocytosis) was highlighted by both gene ontology and pathway enrichment analyses as one of the main functions disturbed by the majority of the metals. Protein–protein network analysis indicated that yeast response to lanthanides relied on proteins that participate in regulatory paths used for calcium (and other biologically relevant cations), and lanthanide toxicity included disruption of biosynthetic pathways by enzyme inhibition. Last, multiple genes and proteins identified in the network analysis have human orthologs, suggesting that those may also be targeted by lanthanides in humans.
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- 2021
25. Complexation of Lanthanides and Heavy Actinides with Aqueous Sulfur-Donating Ligands
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Peter R. Zalupski, Corwin H. Booth, Liane M. Moreau, Travis S. Grimes, Ivan A. Popov, Colt R. Heathman, Kurt F. Smith, Enrique R. Batista, Rebecca J. Abergel, Ping Yang, Nathan P. Bessen, and Jenifer C. Shafer
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chemistry.chemical_classification ,Lanthanide ,Aqueous solution ,010405 organic chemistry ,Inorganic chemistry ,chemistry.chemical_element ,Americium ,Actinide ,010402 general chemistry ,01 natural sciences ,Micelle ,0104 chemical sciences ,Coordination complex ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Thioether ,Stability constants of complexes ,Physical and Theoretical Chemistry - Abstract
The separation of trivalent lanthanides and actinides is challenging because of their similar sizes and charge densities. S-donating extractants have shown significant selectivity for trivalent actinides over lanthanides, with single-stage americium/lanthanide separation efficiencies for some thiol-based extractants reported at >99.999%. While such separations could transform the nuclear waste management landscape, these systems are often limited by the hydrolytic and radiolytic stability of the extractant. Progress away from thiol-based systems is limited by the poorly understood and complex interactions of these extractants in organic phases, where molecular aggregation and micelle formation obfuscates assessment of the metal-extractant coordination environment. Because S-donating thioethers are generally more resistant to hydrolysis and oxidation and the aqueous phase coordination chemistry is anticipated to lack complications brought on by micelle formation, we have considered three thioethers, 2,2'-thiodiacetic acid (TDA), (2R,5S)-tetrahydrothiophene-2,5-dicarboxylic acid, and 2,5-thiophenedicarboxylic acid (TPA), as possible trivalent actinide selective reagents. Formation constants, extended X-ray absorption fine structure spectroscopy, and computational studies were completed for thioether complexes with a variety of trivalent lanthanides and actinides including Nd, Eu, Tb, Am, Cm, Bk, and Cf. TPA was found to have moderately higher selectivity for the actinides because of its ability to bind actinides in a different manner than lanthanides, but the utility of TPA is limited by poor water solubility and high rigidity. While significant competition with water for the metal center limits the efficacy of aqueous-based thioethers for separations, the characterization of these solution-phase, S-containing lanthanide and actinide complexes is the most comprehensively available in the literature to date. This is due to the breadth of lanthanides and actinides considered as well as the techniques deployed and serves as a platform for the further development of S-containing reagents for actinide separations. Additionally, this paper reports on the first bond lengths for Cf and Bk with a neutral S donor.
- Published
- 2021
26. Combining the Best of Two Chelating Titans: A Hydroxypyridinone-Decorated Macrocyclic Ligand for Efficient and Concomitant Complexation and Sensitized Luminescence of f-Elements
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Gauthier J.-P. Deblonde, Liane M. Moreau, Korey P. Carter, Rebecca J. Abergel, Kurt F. Smith, Leticia Arnedo-Sanchez, Toni Tratnjek, Julian A. Rees, and Corwin H. Booth
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Lanthanide ,Coordination sphere ,Extended X-ray absorption fine structure ,010405 organic chemistry ,Ligand ,General Chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Crystallography ,chemistry.chemical_compound ,Cyclen ,chemistry ,Chemical stability ,Chelation ,Macrocyclic ligand - Abstract
An ideal chelator for f-elements features rapid kinetics of complexation, high thermodynamic stability, and slow kinetics of dissociation. Here we present the facile synthesis of a macrocyclic ligand bearing four 1-hydroxy-2-pyridinone units linked to a cyclen scaffold that rapidly forms thermodynamically stable complexes with lanthanides (Sm3+ , Eu3+ , Tb3+ , Dy3+ ) and a representative late actinide (Cm3+ ) in aqueous media and concurrently sensitizes them. Extended X-ray absorption fine structure (EXAFS) spectroscopy revealed an increase in the Ln/An-O bond lengths following the trend Cm>Eu>Tb and EXAFS data were compatible with time-resolved luminescence studies, which indicated one to two water molecules in the inner metal coordination sphere of Eu(III) and two water molecules for the Cm(III) complex. Spectrofluorimetric ligand competition titrations against DTPA confirmed the high thermodynamic stability of DOTHOPO complexes, with pM values between 19.9(1) and 21.9(2).
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- 2021
27. Probing electronic structure in berkelium and californium via an electron microscopy nanosampling approach
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Steven E. Zeltmann, Rebecca J. Abergel, Andrew M. Minor, Gauthier J.-P. Deblonde, Peter Ercius, and Alexander Müller
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Materials science ,Science ,General Physics and Astronomy ,chemistry.chemical_element ,Imaging techniques ,02 engineering and technology ,010402 general chemistry ,Characterization and analytical techniques ,01 natural sciences ,Article ,General Biochemistry, Genetics and Molecular Biology ,Multidisciplinary ,Electron energy loss spectroscopy ,Radiochemistry ,Californium ,Solid-state chemistry ,General Chemistry ,Actinide ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Characterization (materials science) ,Plutonium ,chemistry ,Berkelium ,Transmission electron microscopy ,Nanoparticles ,Atomic number ,0210 nano-technology - Abstract
Due to their rarity and radioactive nature, comparatively little is known about the actinides, particularly those with atomic numbers higher than that of plutonium, and their compounds. In this work, we describe how transmission electron microscopy can provide comprehensive, safe, and cost-effective characterization using only single nanogram amounts of highly-radioactive, solid compounds. Chlorides of the rare elements berkelium and californium are dropcast and then converted in situ to oxides using the electron beam. The f-band occupancies are probed using electron energy loss spectroscopy and an unexpectedly weak spin-orbit-coupling is identified for berkelium. In contrast, californium follows a jj coupling scheme. These results have important implications for the chemistries of these elements and solidify the status of californium as a transitional element in the actinide series., The obtention and study of actinide elements is challenging due to various factors including their radioactivity and scarcity. Herein, the authors characterize the atomic and electronic structure of Am, Cm, Bk, and Cf compounds using a transmission electron microscopy-based workflow that only requires nanogram amounts of the actinide element.
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- 2021
28. Natural abundance oxygen-17 solid-state NMR of metal organic frameworks enhanced by dynamic nuclear polarization
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Diego Carnevale, Geoffrey Bodenhausen, Sujing Wang, Daniel Abergel, Christian Serre, Georges Mouchaham, Mathieu Baudin, Laboratoire des biomolécules (LBM UMR 7203), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut des Matériaux Poreux de Paris (IMAP ), Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques (LCBPT - UMR 8601), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Chimie Moléculaire de Paris Centre (FR 2769), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), and Mouchaham, Georges
- Subjects
Materials science ,Diego ,General Physics and Astronomy ,Protonation ,010402 general chemistry ,01 natural sciences ,Magic Angle Spinning ,chemistry.chemical_compound ,Carnevale ,Wang ,Baudin ,[CHIM]Chemical Sciences ,Carboxylate ,Physical and Theoretical Chemistry ,Polarization (electrochemistry) ,Bodenhausen ,Metal-Organic Frameworks ,Sujing ,Oxygen-17 ,Dynamic Nuclear Polarization ,[CHIM.MATE] Chemical Sciences/Material chemistry ,Mathieu ,010405 organic chemistry ,Christian ,Chemical shift ,Serre ,Nuclear magnetic resonance spectroscopy ,[CHIM.MATE]Chemical Sciences/Material chemistry ,Zirconium-Oxo Clusters ,0104 chemical sciences ,Geoffrey ,chemistry ,Solid-state nuclear magnetic resonance ,Chemical physics ,Physical chemistry ,Oxygen-17 NMR ,Metal-organic framework ,Density functional theory ,Mouchaham ,Georges ,Solid-State NMR - Abstract
International audience; The 17 O resonances of Zirconium-oxo clusters that can be found in porous Zr carboxylate metal-organic frameworks (MOFs) have been investigated by magic-angle spinning (MAS) NMR spectroscopy enhanced by dynamic nuclear polarization (DNP). High-resolution 17 O spectra at 0.037 % natural abundance could be obtained in 48 hours, thanks to DNP enhancement of the 1 H polarization by factors = S with /S without = 28, followed by 1 H 17 O cross-polarization, allowing a saving in experimental time by a factor of ca. 800. The distinct 17 O sites from the oxo-clusters can be resolved at 18.8 T. Their assignment is supported by density functional theory (DFT) calculations of chemical shifts and quadrupolar parameters. Protonation of 17 O sites seems to be leading to large characteristic shifts. Markedly, natural abundance 17 O NMR spectra of diamagnetic MOFs can thus be used to probe and characterize the local environment of different 17 O sites on an atomic scale.
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- 2021
29. Controlling the Reduction of Chelated Uranyl to Stable Tetravalent Uranium Coordination Complexes in Aqueous Solution
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Gauthier J.-P. Deblonde, Rebecca J. Abergel, Toni Tratnjek, Liane M. Moreau, Korey P. Carter, Kurt F. Smith, Julian A. Rees, and Corwin H. Booth
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X-ray absorption spectroscopy ,Aqueous solution ,medicine.diagnostic_test ,010405 organic chemistry ,Inorganic chemistry ,chemistry.chemical_element ,Uranium ,010402 general chemistry ,Uranyl ,01 natural sciences ,Redox ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Spectrophotometry ,medicine ,Chelation ,Physical and Theoretical Chemistry ,Cyclic voltammetry - Abstract
The solution-state interactions between octadentate hydroxypyridinone (HOPO) and catecholamide (CAM) chelating ligands and uranium were investigated and characterized by UV-visible spectrophotometry and X-ray absorption spectroscopy (XAS), as well as electrochemically via spectroelectrochemistry (SEC) and cyclic voltammetry (CV) measurements. Depending on the selected chelator, we demonstrate the controlled ability to bind and stabilize UIV, generating with 3,4,3-LI(1,2-HOPO), a tetravalent uranium complex that is practically inert toward oxidation or hydrolysis in acidic, aqueous solution. At physiological pH values, we are also able to bind and stabilize UIV to a lesser extent, as evidenced by the mix of UIV and UVI complexes observed via XAS. CV and SEC measurements confirmed that the UIV complex formed with 3,4,3-LI(1,2-HOPO) is redox inert in acidic media, and UVI ions can be reduced, likely proceeding via a two-electron reduction process.
- Published
- 2020
30. Developing scandium and yttrium coordination chemistry to advance theranostic radiopharmaceuticals
- Author
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Wayne W. Lukens, Gauthier J.-P. Deblonde, Katherine M. Shield, Dahlia D. An, Trevor D. Lohrey, Korey P. Carter, Tyler A. Bailey, and Rebecca J. Abergel
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Lanthanide ,chemistry.chemical_classification ,010405 organic chemistry ,Ligand ,chemistry.chemical_element ,General Chemistry ,Nuclear magnetic resonance spectroscopy ,Yttrium ,Actinide ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,0104 chemical sciences ,Coordination complex ,lcsh:Chemistry ,chemistry ,lcsh:QD1-999 ,Materials Chemistry ,Biomedical Imaging ,Environmental Chemistry ,Chelation ,Chemical stability - Abstract
The octadentate siderophore analog 3,4,3-LI(1,2-HOPO), denoted 343-HOPO hereafter, is known to have high affinity for both trivalent and tetravalent lanthanide and actinide cations. Here we extend its coordination chemistry to the rare-earth cations Sc3+ and Y3+ and characterize fundamental metal–chelator binding interactions in solution via UV-Vis spectrophotometry, nuclear magnetic resonance spectroscopy, and spectrofluorimetric metal-competition titrations, as well as in the solid-state via single crystal X-ray diffraction. Sc3+ and Y3+ binding with 343-HOPO is found to be robust, with both high thermodynamic stability and fast room temperature radiolabeling, indicating that 343-HOPO is likely a promising chelator for in vivo applications with both metals. As a proof of concept, we prepared a 86Y-343-HOPO complex for in vivo PET imaging, and the results presented herein highlight the potential of 343-HOPO chelated trivalent metal cations for therapeutic and theranostic applications. Radionuclide pairs 44Sc/47Sc and 86Y/90Y possess great promise in the development of theranostic agents, but realizing the full potential of these isotopes necessitates improving rare-earth chelation chemistry. Here the authors show that a hydroxypyridinone-based ligand is a promising candidate for applications in this arena.
- Published
- 2020
31. Open questions in transplutonium coordination chemistry
- Author
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Korey P. Carter, Roger M. Pallares, and Rebecca J. Abergel
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chemistry.chemical_classification ,Engineering ,business.industry ,Nanotechnology ,General Chemistry ,Biochemistry ,Characterization (materials science) ,Coordination complex ,lcsh:Chemistry ,lcsh:QD1-999 ,chemistry ,Materials Chemistry ,Environmental Chemistry ,business - Abstract
Over the past decade, momentous progress has been made in the characterization of late actinide compounds. Here the authors highlight how advances in spectroscopic and computational tools have developed our understanding of fundamental transplutonium bonding interactions, and discuss whether covalency and heterogeneity changes in 5f-orbital bonding could be harnessed in environmentally and industrially relevant systems. Over the past decade, momentous progress has been made in the characterization of late actinide compounds. Here the authors highlight how advances in spectroscopic and computational tools have developed our understanding of fundamental transplutonium bonding interactions, and discuss whether covalency and heterogeneity changes in 5f-orbital bonding could be harnessed in environmentally and industrially relevant systems.
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- 2020
32. Infrared Photon Pair-Production in Ligand-Sensitized Lanthanide Nanocrystals
- Author
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Jacob S. Kanady, Rebecca J. Abergel, and Peter Agbo
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Lanthanide ,education.field_of_study ,energy transfer ,Materials science ,lanthanide ,Infrared ,Population ,downconversion ,Bioengineering ,General Chemistry ,Molecular physics ,Fluorescence ,sensitization ,Ion ,lcsh:Chemistry ,Chemistry ,Pair production ,lcsh:QD1-999 ,Excited state ,Luminescence ,education ,Original Research ,two-photon - Abstract
This report details spectroscopic characterizations of rare-earth, core-shell nanoparticles decorated with the f-element chelator 3,4,3-LI(1,2-HOPO). Evidence of photon downconversion is corroborated through detailed power dependence measurements, which suggest two-photon decay paths are active in these materials, albeit only representing a minority contribution of the sum luminescence, with emission being dominated by normal, Stokes' shifted fluorescence. Specifically, ultraviolet ligand photosensitization of Nd3+ ions in a NaGdF4 host shell results in energy transfer to a Nd3+/Yb3+-doped NaGdF4 nanoparticle core. The population and subsequent decay of core, Yb3+2F5/2 states result in a spectral shift of 620 nm, manifested in a NIR emission displaying luminescence profiles diagnostic of Yb3+ and Nd3+ excited state decays. Emphasis is placed on the generality of this material architecture for realizing ligand-pumped, multi-photon downconversion, with the Nd3+/Yb3+ system presented here functioning as a working prototype for a design principle that may be readily extended to other lanthanide pairs.
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- 2020
33. The rare sugar N-acetylated viosamine is a major component of Mimivirus fibers
- Author
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Sandra Jeudy, Cristina De Castro, Annalisa Salis, Francesco Piacente, Maria Elena Laugieri, Michela Tonetti, Gianluca Damonte, Chantal Abergel, Matteo Gaglianone, Anna Notaro, Information génomique et structurale (IGS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Anna Notaro is recipient of a UIF Vinci program 2015 PhD fellowship (contract C3_90), ANR-14-CE14-0023,Pandoravirus,Caractérisation fonctionnelle et moléculaire des Pandoravirus(2014), Piacente, Francesco, De Castro, Cristina, Jeudy, Sandra, Gaglianone, Matteo, Laugieri, Maria Elena, Notaro, Anna, Salis, Annalisa, Damonte, Gianluca, Abergel, Chantal, and Tonetti, Michela G.
- Subjects
acetyl coenzyme A (acetyl-CoA) ,0301 basic medicine ,Glycan ,Glycosylation ,glycosylation ,Protein Domain ,nuclear magnetic resonance (NMR) ,Acyltransferase ,[SDV]Life Sciences [q-bio] ,Protein domain ,Glycobiology and Extracellular Matrices ,virus ,Biology ,Biochemistry ,Mimiviru ,03 medical and health sciences ,chemistry.chemical_compound ,Protein Domains ,mass spectrometry (MS) ,Molecular Biology ,mass spectrometry ,viosamine ,Bacillosamine ,Mimivirus ,030102 biochemistry & molecular biology ,Cell Biology ,biology.organism_classification ,Rare sugar ,Capsid Protein ,3. Good health ,nuclear magnetic resonance ,030104 developmental biology ,chemistry ,Acetyltransferase ,viru ,biology.protein ,Capsid Proteins ,Mimivirus, acetyl coenzyme A, glycosylation, mass spectrometry, nuclear magnetic resonance, viosamine, virus, Acyltransferases, Capsid Proteins, Glycosylation, Mimiviridae, Protein Domains, Biochemistry, Molecular Biology, Cell Biology ,Mimiviridae ,acetyl coenzyme A ,Acyltransferases - Abstract
International audience; The giant virus Mimivirus encodes an autonomous glycosylation system that is thought to be responsible for the formation of complex and unusual glycans composing the fibers surrounding its icosahedral capsid, including the dideoxyhexose viosamine. Previous studies have identified a gene cluster in the virus genome, encoding enzymes involved in nucleotide-sugar production and glycan formation, but the functional characterization of these enzymes and the full identification of the glycans found in viral fibers remain incomplete. Because viosamine is typically found in acylated forms, we suspected that one of the genes might encode an acyltransferase, providing directions to our functional annotations. Bioinformatic analyses indicated that the L142 protein contains an N-terminal acyltransferase domain and a predicted C-terminal glycosyltransferase. Sequence analysis of the structural model of the L142 N-terminal domain indicated significant homology with some characterized sugar acetyltransferases that modify the C-4 amino group in the bacillosamine or perosamine biosynthetic pathways. Using mass spectrometry and NMR analyses, we confirmed that the L142 N-terminal domain is a sugar acetyltransferase, catalyzing the transfer of an acetyl moiety from acetyl-CoA to the C-4 amino group of UDP-d-viosamine. The presence of acetylated viosamine in vivo has also been confirmed on the glycosylated viral fibers, using GC-MS and NMR. This study represents the first report of a virally encoded sugar acetyltransferase.
- Published
- 2017
34. Mechanisms of defense against products of cysteine catabolism in the nematode Caenorhabditis elegans
- Author
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Rachel Abergel, Arijit Kumar Chatterjee, Einav Gross, Netanel Karbian, Zohar Abergel, and Leonid Livshits
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Paraquat ,0301 basic medicine ,Sulfide ,Hydrogen sulfide ,Longevity ,Sulfides ,Biology ,Endoplasmic Reticulum ,Biochemistry ,Antioxidants ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Physiology (medical) ,Animals ,Cysteine ,Hydrogen Sulfide ,Caenorhabditis elegans ,Caenorhabditis elegans Proteins ,Cysteine metabolism ,chemistry.chemical_classification ,Reactive oxygen species ,Catabolism ,Gastrointestinal Microbiome ,Mitochondria ,Metabolism ,030104 developmental biology ,chemistry ,Mutation ,Unfolded protein response ,Thioredoxin ,Reactive Oxygen Species ,030217 neurology & neurosurgery ,Transcription Factors - Abstract
Cysteine catabolism presents cells with a double-edged sword. On the one hand, cysteine degradation provides cells with essential molecules such as taurine and sulfide. The formation of sulfide in cells is thought to regulate important and diverse physiological processes including blood circulation, synaptic activity and inflammation. On the other hand, the catabolism of cysteine by gut microbiota can release high levels of sulfide that may underlie the development or relapse of ulcerative colitis, an inflammatory bowel disease affecting millions of people worldwide. Here, we have used the nematode C. elegans to explore how cells tolerate high levels of sulfide produced by cysteine degradation in bacteria. We have identified mutations in genes coding for thioredoxin family proteins, mitochondrial proteins, and collagens that confer tolerance to sulfide toxicity. Exposure to sulfide induces the unfolded protein response in the endoplasmic reticulum and mitochondria. Moreover, our results suggest that sulfide toxicity is mediated by reactive oxygen species (ROS). Indeed, pre-treatment of worms with antioxidants increases their tolerance to sulfide toxicity. Intriguingly, sub-toxic levels of the superoxide generator paraquat can also increase the tolerance of worms to sulfide. Therefore, it appears that activation of ROS detoxification pathway prior to the exposure to sulfide, can increase the tolerance to sulfide toxicity. Our results suggest that these detoxification pathways are mediated by the hypoxia inducible factor HIF-1. Finally, we show that sulfide resistance varies among wild C. elegans and other nematode species, suggesting that tolerance to sulfide was naturally selected in certain habitats.
- Published
- 2017
35. Ferritin is regulated by a neuro-intestinal axis in the nematode Caenorhabditis elegans
- Author
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Leonor Romero-Afrima, Einav Gross, Maayan Shaked, Veronica Zelmanovich, Binyamin Zuckerman, Zohar Abergel, Leonid Livshits, Yoav Smith, and Rachel Abergel
- Subjects
0301 basic medicine ,Clinical Biochemistry ,Biochemistry ,Nervous System ,chemistry.chemical_compound ,0302 clinical medicine ,ftn-1 ,Intestinal Mucosa ,Neurotransmitter ,Hypoxia ,lcsh:QH301-705.5 ,Caenorhabditis elegans ,VHL-1 ,lcsh:R5-920 ,biology ,Soluble guanylate cyclases ,Cell Hypoxia ,3. Good health ,Cell biology ,medicine.symptom ,lcsh:Medicine (General) ,Research Paper ,Iron ,Neuropeptide ,03 medical and health sciences ,Downregulation and upregulation ,medicine ,Oxygen sensing neurons ,Animals ,Caenorhabditis elegans Proteins ,Ferritin ,Organic Chemistry ,Neuropeptides ,HIF-1 ,Metabolism ,Hypoxia (medical) ,biology.organism_classification ,Hypoxia-Inducible Factor 1, alpha Subunit ,Oxygen ,030104 developmental biology ,chemistry ,lcsh:Biology (General) ,Gene Expression Regulation ,Ferritins ,EGL-9 ,biology.protein ,030217 neurology & neurosurgery ,Bacteria - Abstract
Iron is vital for the life of most organisms. However, when dysregulated, iron can catalyze the formation of oxygen (O2) radicals that can destroy any biological molecule and thus lead to oxidative injury and death. Therefore, iron metabolism must be tightly regulated at all times, as well as coordinated with the metabolism of O2. However, how is this achieved at the whole animal level is not well understood. Here, we explore this question using the nematode Caenorhabditis elegans. Exposure of worms to O2 starvation conditions (i.e. hypoxia) induces a major upregulation in levels of the conserved iron-cage protein ferritin 1 (ftn-1) in the intestine, while exposure to 21% O2 decreases ftn-1 level. This O2-dependent inhibition is mediated by O2-sensing neurons that communicate with the intestine through neurotransmitter and neuropeptide signalling, and requires the activity of hydroxylated HIF-1. By contrast, the induction of ftn-1 in hypoxia appears to be HIF-1-independent. This upregulation provides protection against Pseudomonas aeruginosa bacteria and oxidative injury. Taken together, our studies uncover a neuro-intestine axis that coordinates O2 and iron responses at the whole animal level., Graphical abstract Image 1, Highlights • The expression of ferritin 1 (ftn-1) is tightly regulated by O2 tension. • O2-sensing neurons inhibit the expression of ftn-1 in the intestine at 21% O2. • Hydroxylated–HIF–1 inhibits the expression of ftn-1 at 21% O2. • ftn-1 is important for protecting against Pseudomonas aeruginosa bacteria.
- Published
- 2019
36. A Case of Wernicke’s Encephalopathy in a Pregnant Woman With a History of Sleeve Gastrectomy
- Author
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Abhishek Polavarapu, Jeffrey Abergel, Jobin Philipose, Harika Kandlakunta, and Dhineshreddy Gurala
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Acute confusion ,Sleeve gastrectomy ,Pediatrics ,medicine.medical_specialty ,Ataxia ,Malabsorption ,malabsorption ,bariatric surgery ,medicine.medical_treatment ,Encephalopathy ,wernicke's encephalopathy ,030204 cardiovascular system & hematology ,medicine.disease_cause ,Wernicke's encephalopathy ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,pregnant ,medicine ,Thiamine deficiency ,thiamine deficiency ,business.industry ,Gastric bypass surgery ,Gastroenterology ,General Engineering ,nutritional deficiency ,restrictive surgery ,medicine.disease ,chemistry ,medicine.symptom ,business ,sleeve gastrectomy ,030217 neurology & neurosurgery - Abstract
Wernicke’s encephalopathy (WE) is a neurological complication of thiamine deficiency characterized by a triad of acute confusion, ataxia, and ophthalmoplegia. Even though it is most common in chronic alcoholism, an increase in prevalence has been reported recently due to the increased popularity of bariatric surgeries. WE is a known neurological complication after gastric bypass surgery but rarely reported after sleeve gastrectomy. We present a unique case of WE in pregnant women four months after sleeve gastrectomy.
- Published
- 2020
37. Rapid Detection of Gadolinium-Based Contrast Agents in Urine with a Chelated Europium Luminescent Probe
- Author
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Dahlia D. An, Roger M. Pallares, Rebecca J. Abergel, Pariswi Tewari, and Elizabeth T Wang
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Luminescence ,Gadolinium ,chemistry.chemical_element ,Contrast Media ,Bioengineering ,02 engineering and technology ,Urine ,01 natural sciences ,Excretion ,Mice ,Europium ,medicine ,Animals ,Chelation ,Sample preparation ,Instrumentation ,Fluid Flow and Transfer Processes ,Quenching (fluorescence) ,Chromatography ,medicine.diagnostic_test ,Process Chemistry and Technology ,010401 analytical chemistry ,Magnetic resonance imaging ,021001 nanoscience & nanotechnology ,Magnetic Resonance Imaging ,0104 chemical sciences ,chemistry ,0210 nano-technology - Abstract
Gadolinium-based contrast agents are widely used in magnetic resonance imaging procedures to enhance image contrast. Despite their ubiquitous use in clinical settings, gadolinium is not an innocuous element, as suggested by several disorders associated with its use. Therefore, novel analytical technologies capable of tracking contrast agent excretion through urine are necessary for optimizing patient safety after imaging procedures. Here, we describe an assay to detect and quantify contrast agents in urine based on the luminescence quenching of a metal chelate probe, Eu3+-3,4,3-LI(1,2-HOPO), which only requires 10 min incubation before measurement. Gadolinium-based contrast agents prevent the formation of the Eu3+-3,4,3-LI(1,2-HOPO) complex, subsequently decreasing the luminescence of the assay solution. Three commercial contrast agents, Magnevist, Multihance, and Omniscan, were used to demonstrate the analytical concept in synthetic human urine, and subsequent quantification of mouse urine samples. To the best of our knowledge, this is the first assay capable of detecting and quantifying gadolinium-based contrast agents in urine without sample preparation or digestion.
- Published
- 2020
38. Selective Lanthanide Sensing with Gold Nanoparticles and Hydroxypyridinone Chelators
- Author
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Andrew M. Minor, Steven E. Zeltmann, Roger M. Pallares, Rebecca J. Abergel, Toni Tratnjek, and Korey P. Carter
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Lanthanide ,Chemical substance ,010405 organic chemistry ,Chemistry ,Nanoparticle ,010402 general chemistry ,01 natural sciences ,Combinatorial chemistry ,0104 chemical sciences ,Inorganic Chemistry ,Colloidal gold ,Particle growth ,Chelation ,Physical and Theoretical Chemistry - Abstract
The octadentate hydroxypyridinone chelator 3,4,3-LI(1,2-HOPO) is a promising therapeutic agent because of its high affinity for f-block elements and noncytotoxicity at medical dosages. The interaction between 3,4,3-LI(1,2-HOPO) and other biomedically relevant metals such as gold, however, has not been explored. Gold nanoparticles functionalized with chelators have demonstrated great potential in theranostics, yet thus far, no protocol that combines 3,4,3-LI(1,2-HOPO) and colloidal gold has been developed. Here, we characterize the solution thermodynamic properties of the complexes formed between 3,4,3-LI(1,2-HOPO) and Au3+ ions and demonstrate how under specific pH conditions the chelator promotes the growth of gold nanoparticles, acting as both reducing and stabilizing agent. 3,4,3-LI(1,2-HOPO) ligands on the nanoparticle surface remain active and selective toward f-block elements, as evidenced by gold nanoparticle selective aggregation. Finally, a new colorimetric assay capable of reaching the detection levels necessary for the quantification of lanthanides in waste from industrial processes is developed based on the inhibition of particle growth by lanthanides.
- Published
- 2020
39. The DNA methylation landscape of giant viruses
- Author
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Jean-Michel Claverie, Sandra Jeudy, Jean-Marie Alempic, Matthieu Legendre, Chantal Abergel, Sofia Rigou, Information génomique et structurale (IGS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and Assistance Publique - Hôpitaux de Marseille (APHM)
- Subjects
0301 basic medicine ,Epigenomics ,Methyltransferase ,Genes, Viral ,Marseilleviridae ,viruses ,General Physics and Astronomy ,Genome ,chemistry.chemical_compound ,Epigenome ,lcsh:Science ,ComputingMilieux_MISCELLANEOUS ,Phylogeny ,Genetics ,0303 health sciences ,Multidisciplinary ,DNA methylation ,biology ,Methylation ,DNA Restriction Enzymes ,Biological Evolution ,3. Good health ,[SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology ,Virophages ,Science ,030106 microbiology ,Genome, Viral ,General Biochemistry, Genetics and Molecular Biology ,Article ,Host-Parasite Interactions ,03 medical and health sciences ,Mimiviridae ,Giant Virus ,DNA Restriction-Modification Enzymes ,Epigenetics ,Viral evolution ,Gene ,030304 developmental biology ,030306 microbiology ,General Chemistry ,Methyltransferases ,biology.organism_classification ,Restriction enzyme ,030104 developmental biology ,chemistry ,Giant Viruses ,lcsh:Q ,DNA - Abstract
DNA methylation is an important epigenetic mark that contributes to various regulations in all domains of life. Giant viruses are widespread dsDNA viruses with gene contents overlapping the cellular world that also encode DNA methyltransferases. Yet, virtually nothing is known about the methylation of their DNA. Here, we use single-molecule real-time sequencing to study the complete methylome of a large spectrum of giant viruses. We show that DNA methylation is widespread, affecting 2/3 of the tested families, although unevenly distributed. We also identify the corresponding viral methyltransferases and show that they are subject to intricate gene transfers between bacteria, viruses and their eukaryotic host. Most methyltransferases are conserved, functional and under purifying selection, suggesting that they increase the viruses’ fitness. Some virally encoded methyltransferases are also paired with restriction endonucleases forming Restriction-Modification systems. Our data suggest that giant viruses’ methyltransferases are involved in diverse forms of virus-pathogens interactions during coinfections., DNA methylation is an epigenetic marker in all domains of life. Here, Jeudy et al., using single-molecule realtime sequencing, determine DNA methylation patterns in giant viruses and evolutionary analysis of virus encoded DNA methyltransferases suggests that they affect viral fitness.
- Published
- 2020
40. Hypercoagulability (thrombin generation) in patients with cirrhosis is detected with ST-Genesia
- Author
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Aurélien Lebreton, Sylvie Massoulié, Armand Abergel, Thomas Sinegre, Thomas Lecompte, Laurie Talon, and Bruno Pereira
- Subjects
Liver Cirrhosis ,medicine.medical_specialty ,Cirrhosis ,Plasma samples ,Chemistry ,Thrombin ,Hematology ,030204 cardiovascular system & hematology ,medicine.disease ,Thrombomodulin ,Thrombin generation ,Gastroenterology ,03 medical and health sciences ,Plasma ,0302 clinical medicine ,Endogenous Thrombin Potential ,Internal medicine ,Reagent ,medicine ,Humans ,Thrombophilia ,In patient ,Blood Coagulation Tests ,Blood coagulation test - Abstract
Background Thrombin generation assays (TGAs) performed with calibrated automated thrombography (CAT) in the presence of thrombomodulin (TM) indicate plasma hypercoagulability in cirrhosis. Objective To evaluate, in the presence of TM, the new ST-Genesia automated device developed for improving TGA vs the previously used CAT method, with plasma samples of patients with cirrhosis. Patients/methods Platelet-poor plasma samples were prepared from citrated blood samples of 52 healthy controls and 85 patients with cirrhosis (severity evaluated using the Child-Pugh score [CP]). TGAs were performed using CAT with PPP-Reagent and ST-Genesia with the STG-ThromboScreen reagent, in the presence of TM. Endogenous thrombin potential (ETP) was chosen as the main parameter. Results Whatever the method, ETP values were higher in patients than in healthy controls. All patients identified as hypercoagulable with ST-Genesia and STG-ThromboScreen were found hypercoagulable with CAT and PPP-Reagent. Conversely, eight and ten patients in the CP-A and CP-B classes respectively were identified as hypercoagulable only with CAT. The use of ST-Genesia with the STG-ThromboScreen reagent with TM led to a bias, with higher ETP values for healthy controls and lower for patients compared with CAT. Crossover analysis (CAT with the STG-ThromboScreen reagent) evidenced a substantial effect of the STG-ThromboScreen reagent; the analyzer (including calibration and data analysis) plays a lesser role. Conclusion ST-Genesia evidences hypercoagulability in patients with cirrhosis when TG is studied in the presence of TM, but the results are not interchangeable with those obtained with CAT.
- Published
- 2020
41. Weak calcium-mediated interactions between lewis x-related trisaccharides studied by NMR measurements of residual dipolar couplings
- Author
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Nodet, Gabrielle, Poggi, Luisa, Abergel, Daniel, Gourmala, Chafika, Dengxiang, Dong, Yongmin Zhang, Mallet, Jean-Maurice, and Bodenhausen, Geoffrey
- Subjects
Nuclear magnetic resonance -- Usage ,Carbohydrates -- Chemical properties ,Cell interaction -- Analysis ,Chemistry - Abstract
The lewis X ([Le.sup.X]) determinant, a trisaccharide with the carbohydrate sequence Galbeta(1-4)- [Fucalpha(1-3)]GlcNAcbeta, is believed to be responsible for [Ca.sup.2} -mediated cell-cell interactions. The first direct observation in solution of calcium mediated interaction between [Le.sup.x] molecules is presented.
- Published
- 2007
42. Networks of Coupled Rotators: Relationship between structures and internal dynamics in metal-binding proteins: Applications to apo- and holo-calbindin
- Author
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Dhulesia, Anne, Abergel, Daniel, and Bodenhausen, Geoffrey
- Subjects
Calcium-binding proteins -- Chemical properties ,Calcium-binding proteins -- Structure ,Chemistry - Abstract
The relationship between the structures and internal dynamics of the C[a.sup.2-] binding protein calbindin is analyzed, which is normally based on the newly developed Networks of Coupled Rotators (NCRs). The incorporation into the NCR model proves the presence of weak interactions between the calcium and oxygen atoms and hence shows that it can be used for the study of many other systems.
- Published
- 2007
43. 12 Weeks of a Ribavirin‐Free Sofosbuvir and Nonstructural Protein 5A Inhibitor Regimen Is Enough to Treat Recurrence of Hepatitis C After Liver Transplantation
- Author
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Audrey Coilly, Carole Cagnot, Pascal Lebray, Stéphane Chevaliez, Alpha Diallo, Victor de Lédinghen, Jean-Charles Duclos-Vallée, Danielle Botta-Fridlund, Claire Francoz, Camille Besch, Nassim Kamar, Christine Silvain, P. Perré, Albert Tran, Jérôme Dumortier, François Habersetzer, Claire Fougerou-Leurent, Aurelie Veislinger, Valérie Canva, Vincent Di Martino, Georges-Philippe Pageaux, Filomena Conti, Caroline Jezequel, Christophe Duvoux, Armando Abergel, Christophe Moreno, Sylvie Radenne, Maryline Debette-Gratien, H. Montialoux, Emilie Rossignol, Vincent Leroy, Louis d’Alteroche, and Pauline Houssel-Debry
- Subjects
Liver Cirrhosis ,Male ,Sofosbuvir ,medicine.medical_treatment ,Viral Nonstructural Proteins ,030230 surgery ,Liver transplantation ,medicine.disease_cause ,Gastroenterology ,chemistry.chemical_compound ,0302 clinical medicine ,Belgium ,Recurrence ,Prospective Studies ,10. No inequality ,education.field_of_study ,Graft Survival ,virus diseases ,Hepatitis C ,Middle Aged ,Sciences bio-médicales et agricoles ,Prognosis ,3. Good health ,Treatment Outcome ,Disease Progression ,Drug Therapy, Combination ,Female ,030211 gastroenterology & hepatology ,France ,Viral load ,medicine.drug ,Adult ,medicine.medical_specialty ,Hepatitis C virus ,Population ,Drug Administration Schedule ,03 medical and health sciences ,Internal medicine ,Ribavirin ,medicine ,Humans ,education ,Aged ,Dose-Response Relationship, Drug ,Hepatology ,business.industry ,Hepatitis C, Chronic ,medicine.disease ,digestive system diseases ,Liver Transplantation ,Regimen ,chemistry ,business - Abstract
Sofosbuvir (SOF) combined with nonstructural protein 5A (NS5A) inhibitors has demonstrated its efficacy in treating a recurrence of hepatitis C virus (HCV) after liver transplantation (LT). However, the duration of treatment and need for ribavirin (RBV) remain unclear in this population. Our aim was to determine whether LT recipients could be treated with an SOF + NS5A inhibitor-based regimen without RBV for 12 weeks post-LT. Between October 2013 and December 2015, 699 LT recipients experiencing an HCV recurrence were enrolled in the multicenter ANRS CO23 CUPILT cohort. We selected patients receiving SOF and NS5A inhibitor ± RBV and followed for at least 12 weeks after treatment discontinuation. The primary efficacy endpoint was a sustained virological response 12 weeks after the end of treatment (SVR12). Among these 699 patients, 512 fulfilled the inclusion criteria. Their main characteristics were: 70.1% genotype 1, 18.2% genotype 3, 21.1% cirrhosis, and 34.4% previously treated patients. We identified four groups of patients according to their treatment and duration: SOF + NS5A without RBV for 12 (156 patients) or 24 (239 patients) weeks; SOF + NS5A + RBV for 12 (47 patients) or 24 (70 patients) weeks. SVR12 values reached 94.9%, 97.9%, 95.7%, and 92.9%, respectively (P = 0.14). Only 20 patients experienced a treatment failure. Under multivariate analysis, factors such as fibrosis stage, previous treatment, HCV genotype, and baseline HCV viral load did not influence SVR12 rates in the four groups (P = 0.21). Hematological adverse events (AEs) were more common in the RBV group: anemia (P < 0.0001) and blood transfusion (P = 0.0001). Conclusion: SOF + NS5A inhibitors without RBV for 12 weeks constituted reliable therapy for recurrent HCV post-LT with an excellent SVR12 whatever the fibrosis stage, HCV genotype, and previous HCV treatment. (Hepatology 2018; 00:000-000)., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2018
44. Spontaneous Chelation-Driven Reduction of the Neptunyl Cation in Aqueous Solution
- Author
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Julian A. Rees, Corwin H. Booth, Liane M. Moreau, Katherine M. Shield, Kurt F. Smith, Korey P. Carter, Toni Tratnjek, and Rebecca J. Abergel
- Subjects
Absorption spectroscopy ,Extended X-ray absorption fine structure ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Inorganic chemistry ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Redox ,Catalysis ,XANES ,0104 chemical sciences ,Oxidation state ,Reactivity (chemistry) ,Chelation ,Cyclic voltammetry - Abstract
Octadentate hydroxypyridinone (HOPO) and catecholamide (CAM) siderophore analogues are known to be efficacious chelators of the actinide cations, and these ligands are also capable of facilitating both activation and reduction of actinyl species. Utilizing X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopies, as well as cyclic voltammetry measurements, herein, we elucidate chelation-based mechanisms for driving reactivity and initiating redox processes in a family of neptunyl-HOPO and CAM complexes. Based on the selected chelator, the ability to control the oxidation state of neptunium and the speed of reduction and concurrent oxo group activation was demonstrated. Most notably, reduction kinetics for the NpV O2 +/ /NpIV redox couple upon chelation by the ligands 3,4,3-LI(1,2-HOPO) and 3,4,3-LI(CAM)2 (1,2-HOPO)2 was observed to be faster than ever reported, and in fact quicker than we could measure using either X-ray absorption spectroscopy or electrochemical techniques.
- Published
- 2019
45. ENCAPSULATED 3,4,3-LI(1,2-HOPO) IN CHITOSAN NANOPARTICLES FOR DECORPORATION VIA INHALATION
- Author
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Chunsheng Li, Sijing Chen, Rebecca J. Abergel, Edward P. C. Lai, Heather Wyatt, and Raymond Ko
- Subjects
Actinoid Series Elements ,Pyridones ,Nanoparticle ,02 engineering and technology ,Radiation Dosage ,030218 nuclear medicine & medical imaging ,Chitosan ,Heterocyclic Compounds, 1-Ring ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,In vivo ,Oral administration ,Administration, Inhalation ,Humans ,Radiology, Nuclear Medicine and imaging ,Lung ,Decontamination ,Chelating Agents ,Inhalation exposure ,Americium ,Radiation ,Radiological and Ultrasound Technology ,Inhalation ,Chemistry ,Radiochemistry ,Public Health, Environmental and Occupational Health ,General Medicine ,Chitosan nanoparticles ,Pentetic Acid ,021001 nanoscience & nanotechnology ,Plutonium ,Body Fluids ,Nanoparticles ,Nanomedicine ,0210 nano-technology - Abstract
3,4,3-LI(1,2-HOPO) has been identified as an excellent alternative for DTPA for decorporating actinides, such as Pu and Am, after internal contamination. Efforts have been focused on its application through oral administration. When 3,4,3-LI(1,2-HOPO) was encapsulated with biocompatible, biodegradable nanoparticles made of chitosan, its release from the nanoparticles to lung fluid, observed in in vitro experiments, exhibited an extended release profile. These observations were very encouraging, as this nanomedicine could lead to a reduction in the dosing frequency required to achieve the decorporation efficacy of unformulated 3,4,3-LI(1,2-HOPO) itself. In vivo release tests as well as actinide decorporation experiments, using an inhalation exposure animal model, will follow.
- Published
- 2018
46. Rates of Chemical Reactions Embedded in a Metabolic Network by Dissolution Dynamic Nuclear Polarisation NMR
- Author
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Aditya Jhajharia, Aude Sadet, Daniel Abergel, Dennis Kurzbach, Emeric Miclet, Geoffrey Bodenhausen, Emmanuelle M. M. Weber, Laboratoire des biomolécules (LBM UMR 7203), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM), Structure et Dynamique des Biomolécules (LBM-E3), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Département de Chimie - ENS Paris, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Département de Chimie - ENS Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)
- Subjects
0301 basic medicine ,Magnetic Resonance Spectroscopy ,Metabolic network ,010402 general chemistry ,Gluconates ,01 natural sciences ,Chemical reaction ,Catalysis ,Pentose Phosphate Pathway ,Reaction rate ,03 medical and health sciences ,Hydrolysis ,Computational chemistry ,[CHIM]Chemical Sciences ,Dissolution ,Chemistry ,Organic Chemistry ,Dynamic nuclear polarisation ,General Chemistry ,0104 chemical sciences ,Kinetics ,030104 developmental biology ,Solubility ,Scientific method ,Isomerization ,Metabolic Networks and Pathways - Abstract
International audience; The isomerisation of 6-phosphogluconolactones and their hydrolyses into 6-phosphogluconic acid form a non enzymatic side cycle of the pentose-phosphate pathway (PPP) in cells. We show that dissolution dynamic nuclear polarization can be used for determining the kinetic rates of the involved transformations in real time. It is found that the hydrolysis of both lactones is significantly slower than the isomeration process, thereby shedding new light onto this subtle chemical process.
- Published
- 2018
47. Spectroscopic and Computational Characterization of Diethylenetriaminepentaacetic Acid/Transplutonium Chelates: Evidencing Heterogeneity in the Heavy Actinide(III) Series
- Author
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Corwin H. Booth, Rebecca J. Abergel, Morgan P. Kelley, Enrique R. Batista, Jing Su, Gauthier J.-P. Deblonde, and Ping Yang
- Subjects
Lanthanide ,Aqueous solution ,Extended X-ray absorption fine structure ,010405 organic chemistry ,chemistry.chemical_element ,General Chemistry ,Actinide ,010402 general chemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Bond length ,Berkelium ,chemistry ,Molecule ,Physical chemistry ,Density functional theory - Abstract
The chemistry of trivalent transplutonium ions (Am3+ , Cm3+ , Bk3+ , Cf3+ , Es3+ …) is usually perceived as monotonic and paralleling that of the trivalent lanthanide series. Herein, we present the first extended X-ray absorption fine structure (EXAFS) study performed on a series of aqueous heavy actinide chelates, extending past Cm. The results obtained on diethylenetriaminepentaacetic acid (DTPA) complexes of trivalent Am, Cm, Bk, and Cf show a break to much shorter metal-oxygen nearest-neighbor bond lengths in the case of Cf3+ . Corroborating those results, density functional theory calculations, extended to Es3+ , suggest that the shorter Cf-O and Es-O bonds could arise from the departure of the coordinated water molecule and contraction of the ligand around the metal relative to the other [MIII DTPA(H2 O)]2- (M=Am, Cm, Bk) complexes. Taken together, these experimental and theoretical results demonstrate inhomogeneity within the trivalent transplutonium series that has been insinuated and debated in recent years, and that may also be leveraged for future nuclear waste reprocessing technologies.
- Published
- 2018
48. Enterobactin protonation and iron release: Structural characterization of the salicylate coordination shift in ferric enterobactin
- Author
-
Abergel, Rebecca J., Warner, Jeffrey A., Shuh, David K., and Raymond, Kenneth N.
- Subjects
Iron compounds -- Chemical properties ,Salicylates -- Chemical properties ,Enterobacter -- Research ,Enterobacteriaceae -- Research ,Bacterial proteins -- Structure ,Bacterial proteins -- Chemical properties ,Chemistry - Abstract
The siderophore enterobactin (Ent), which is produced by many species of enteric bacteria to mediate iron uptake is described. The ferric salicylate complexes display quasi-reversible reduction potentials from -89 to -551 mV, which supports the feasibility of a low pH iron release mechanism facilitated by biological reductants.
- Published
- 2006
49. Coimmunoprecipitation of reversibly glycosylated polypeptide with sucrose synthase from developing castor oilseeds
- Author
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Eric T. Fedosejevs, Yi-Min She, Leo N.C. Liu, William C. Plaxton, and Megan Abergel
- Subjects
Proteomics ,0106 biological sciences ,0301 basic medicine ,Glycosylation ,Sucrose ,Immunoprecipitation ,Biophysics ,Biology ,Blotting, Far-Western ,01 natural sciences ,Biochemistry ,Interactome ,03 medical and health sciences ,chemistry.chemical_compound ,Tandem Mass Spectrometry ,Structural Biology ,Protein Interaction Mapping ,Genetics ,Molecular Biology ,Phylogeny ,Glycoproteins ,Plant Proteins ,chemistry.chemical_classification ,Ricinus ,Cell Biology ,Castor Bean ,biology.organism_classification ,Blot ,030104 developmental biology ,chemistry ,Glucosyltransferases ,biology.protein ,Sucrose synthase ,Glycoprotein ,010606 plant biology & botany - Abstract
The sucrose synthase (SUS) interactome of developing castor oilseeds (COS; Ricinus communis) was assessed using coimmunoprecipitation (co-IP) with anti-(COS RcSUS1)-IgG followed by proteomic analysis. A 41-kDa polypeptide (p41) that coimmunoprecipitated with RcSUS1 from COS extracts was identified as reversibly glycosylated polypeptide-1 (RcRGP1) by LC-MS/MS and anti-RcRGP1 immunoblotting. Reciprocal Far-western immunodot blotting corroborated the specific interaction between RcSUS1 and RcRGP1. Co-IP using anti-(COS RcSUS1)-IgG and clarified extracts from other developing seeds as well as cluster (proteoid) roots of white lupin and Harsh Hakea consistently recovered 90 kDa SUS polypeptides along with p41/RGP as a SUS interactor. The results suggest that SUS interacts with RGP in diverse sink tissues to channel UDP-glucose derived from imported sucrose into hemicellulose and/or glycoprotein/glycolipid biosynthesis.
- Published
- 2017
50. Characterizing Thermal Mixing Dynamic Nuclear Polarization via Cross-Talk between Spin Reservoirs
- Author
-
Geoffrey Bodenhausen, Dennis Kurzbach, David Guarin, Konstantin L. Ivanov, Alberto Rosso, Daniel Abergel, Sina Marhabaie, Laboratoire des biomolécules (LBM UMR 7203), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Chimie Moléculaire de Paris Centre (FR 2769), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Novosibirsk State University (NSU), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), and Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)
- Subjects
Chemistry ,Radical ,Physics::Medical Physics ,Time evolution ,Analytical chemistry ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Polarization (waves) ,01 natural sciences ,Nitroxide radical ,0104 chemical sciences ,Magnetic field ,[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry ,Chemical physics ,Thermal ,General Materials Science ,Hyperpolarization (physics) ,Physical and Theoretical Chemistry ,0210 nano-technology ,Spectroscopy - Abstract
International audience; Dynamic nuclear polarization (DNP) embraces a family of methods to increase signal intensities in nuclear magnetic resonance (NMR) spectroscopy. Despite extensive theoretical work that allows one to distinguish at least five distinct mechanisms, it remains challenging to determine the relative weights of the processes that are responsible for DNP in state-of-the-art experiments operating with stable organic radicals like nitroxides at high magnetic fields and low temperatures. Specifically, determining experimental conditions where DNP involves thermal mixing, which denotes a spontaneous heat exchange between different spin reservoirs, remains challenging. We propose an experimental approach to ascertain the prevalence of the thermal mixing regime by monitoring characteristic signature properties of the time evolution of the hyperpolarization. We find that thermal mixing is the dominant DNP mechanism at high nitroxide radical concentrations, while a mixture of different mechanisms prevails at lower concentrations.
- Published
- 2017
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