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1. The effect of (NH4)2SO4 on the freezing properties of non-mineral dust ice nucleating substances of atmospheric relevance

Author

Soleil Worthy, Anand Kumar, Yu Xi, Jingwei Yun, Jessie Chen, Cuishan Xu, Victoria Irish, Pierre Amato, Allan Bertram, Institut de Chimie de Clermont-Ferrand (ICCF), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national polytechnique Clermont Auvergne (INP Clermont Auvergne), Université Clermont Auvergne (UCA)-Université Clermont Auvergne (UCA), STMicroelectronics [India] (ST-INDIA), Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), and SIGMA Clermont (SIGMA Clermont)-Institut de Chimie du CNRS (INC)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)

Subjects
Chemistry, Physics, QC1-999, [SDE]Environmental Sciences, [CHIM]Chemical Sciences, QD1-999, complex mixtures
Abstract

A wide range of materials including mineral dust, soil dust, and bioaerosols have been shown to act as ice nuclei in the atmosphere. During atmospheric transport, these materials can become coated with inorganic and organic solutes which may impact their ability to nucleate ice. While a number of studies have investigated the impact of solutes at low concentrations on ice nucleation by mineral dusts, very few studies have examined their impact on non-mineral dust ice nuclei. We studied the effect of dilute (NH4)2SO4 solutions (0.05 M) on immersion freezing of a variety of non-mineral dust ice-nucleating substances (INSs) including bacteria, fungi, sea ice diatom exudates, sea surface microlayer substances, and humic substances using the droplet-freezing technique. We also studied the effect of (NH4)2SO4 solutions (0.05 M) on the immersion freezing of several types of mineral dust particles for comparison purposes. (NH4)2SO4 had no effect on the median freezing temperature (ΔT50) of 9 of the 10 non-mineral dust materials tested. There was a small but statistically significant decrease in ΔT50 (−0.43 ± 0.19 ∘C) for the bacteria Xanthomonas campestris in the presence of (NH4)2SO4 compared to pure water. Conversely, (NH4)2SO4 increased the median freezing temperature of four different mineral dusts (potassium-rich feldspar, Arizona Test Dust, kaolinite, montmorillonite) by 3 to 9 ∘C and increased the ice nucleation active site density per gram of material (nm(T)) by a factor of ∼ 10 to ∼ 30. This significant difference in the response of mineral dust and non-mineral dust ice-nucleating substances when exposed to (NH4)2SO4 suggests that they nucleate ice and/or interact with (NH4)2SO4 via different mechanisms. This difference suggests that the relative importance of mineral dust to non-mineral dust particles for ice nucleation in mixed-phase clouds could potentially increase as these particles become coated with (NH4)2SO4 in the atmosphere. This difference also suggests that the addition of (NH4)2SO4 (0.05 M) to atmospheric samples of unknown composition could potentially be used as an indicator or assay for the presence of mineral dust ice nuclei, although additional studies are still needed as a function of INS concentration to confirm the same trends are observed for different INS concentrations than those used here. A comparison with results in the literature does suggest that our results may be applicable to a range of mineral dust and non-mineral dust INS concentrations.

Published
2022
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2. Overview paper: New insights into aerosol and climate in the Arctic

Author

J. P. D. Abbatt, W. R. Leaitch, A. A. Aliabadi, A. K. Bertram, J.-P. Blanchet, A. Boivin-Rioux, H. Bozem, J. Burkart, R. Y. W. Chang, J. Charette, J. P. Chaubey, R. J. Christensen, A. Cirisan, D. B. Collins, B. Croft, J. Dionne, G. J. Evans, C. G. Fletcher, M. Galí, R. Ghahremaninezhad, E. Girard, W. Gong, M. Gosselin, M. Gourdal, S. J. Hanna, H. Hayashida, A. B. Herber, S. Hesaraki, P. Hoor, L. Huang, R. Hussherr, V. E. Irish, S. A. Keita, J. K. Kodros, F. Köllner, F. Kolonjari, D. Kunkel, L. A. Ladino, K. Law, M. Levasseur, Q. Libois, J. Liggio, M. Lizotte, K. M. Macdonald, R. Mahmood, R. V. Martin, R. H. Mason, L. A. Miller, A. Moravek, E. Mortenson, E. L. Mungall, J. G. Murphy, M. Namazi, A.-L. Norman, N. T. O'Neill, J. R. Pierce, L. M. Russell, J. Schneider, H. Schulz, S. Sharma, M. Si, R. M. Staebler, N. S. Steiner, J. L. Thomas, K. von Salzen, J. J. B. Wentzell, M. D. Willis, G. R. Wentworth, J.-W. Xu, J. D. Yakobi-Hancock, Department of Chemistry [University of Toronto], University of Toronto, Environment and Climate Change Canada, School of Engineering [Guelph], University of Guelph, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Département des sciences de la terre et de l'atmosphère [Montréal] (SCTA), Université du Québec à Montréal = University of Québec in Montréal (UQAM), Institut des Sciences de la MER de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Institute for Atmospheric Physics [Mainz] (IPA), Johannes Gutenberg - Universität Mainz (JGU), Aerosol Physics and Environmental Physics [Vienna], University of Vienna [Vienna], Department of Physics and Atmospheric Science [Halifax], Dalhousie University [Halifax], Department of Chemistry [Lewisburg], Bucknell University, Department of Chemical Engineering and Applied Chemistry (CHEM ENG), Department of Geography and Environmental Management [Waterloo], University of Waterloo [Waterloo], Department of Biology [Québec], Université Laval [Québec] (ULaval), Departement de Biologie [Québec], School of Earth and Ocean Sciences [Victoria] (SEOS), University of Victoria [Canada] (UVIC), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Centre d'Applications et de Recherches en TELédétection [Sherbrooke] (CARTEL), Département de géomatique appliquée [Sherbrooke] (UdeS), Université de Sherbrooke (UdeS)-Université de Sherbrooke (UdeS), Department of Atmospheric Science [Fort Collins], Colorado State University [Fort Collins] (CSU), Particle Chemistry Department [Mainz], Max Planck Institute for Chemistry (MPIC), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Centro de Ciencias de la Atmosfera [Mexico], Universidad Nacional Autónoma de México (UNAM), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Air Quality Processes Research Section, Canadian Centre for Climate Modelling and Analysis (CCCma), Institute of Ocean Sciences [Sidney] (IOS), Fisheries and Oceans Canada (DFO), Department of Mathematics [Isfahan], University of Isfahan, Department of Physics and Astronomy [Calgary], University of Calgary, Scripps Institution of Oceanography (SIO), University of California [San Diego] (UC San Diego), University of California-University of California, Institut des Géosciences de l’Environnement (IGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Recherche pour le Développement (IRD)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Alberta Environment and Parks (AEP), National Research Council of Canada (NRC), Johannes Gutenberg - Universität Mainz = Johannes Gutenberg University (JGU), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Scripps Institution of Oceanography (SIO - UC San Diego), University of California (UC)-University of California (UC), and Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Arctic haze, Atmospheric Science, 010504 meteorology & atmospheric sciences, Global warming, Climate change, 010501 environmental sciences, Mineral dust, Atmospheric sciences, 01 natural sciences, Sea surface microlayer, lcsh:QC1-999, Atmospheric Sciences, Aerosol, lcsh:Chemistry, Climate Action, Deposition (aerosol physics), lcsh:QD1-999, Arctic, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, 13. Climate action, Meteorology & Atmospheric Sciences, lcsh:Physics, Astronomical and Space Sciences, 0105 earth and related environmental sciences
Abstract

Motivated by the need to predict how the Arctic atmosphere will change in a warming world, this article summarizes recent advances made by the research consortium NETCARE (Network on Climate and Aerosols: Addressing Key Uncertainties in Remote Canadian Environments) that contribute to our fundamental understanding of Arctic aerosol particles as they relate to climate forcing. The overall goal of NETCARE research has been to use an interdisciplinary approach encompassing extensive field observations and a range of chemical transport, earth system, and biogeochemical models. Several major findings and advances have emerged from NETCARE since its formation in 2013. (1) Unexpectedly high summertime dimethyl sulfide (DMS) levels were identified in ocean water (up to 75 nM) and the overlying atmosphere (up to 1 ppbv) in the Canadian Arctic Archipelago (CAA). Furthermore, melt ponds, which are widely prevalent, were identified as an important DMS source (with DMS concentrations of up to 6 nM and a potential contribution to atmospheric DMS of 20 % in the study area). (2) Evidence of widespread particle nucleation and growth in the marine boundary layer was found in the CAA in the summertime, with these events observed on 41 % of days in a 2016 cruise. As well, at Alert, Nunavut, particles that are newly formed and grown under conditions of minimal anthropogenic influence during the months of July and August are estimated to contribute 20 % to 80 % of the 30–50 nm particle number density. DMS-oxidation-driven nucleation is facilitated by the presence of atmospheric ammonia arising from seabird-colony emissions, and potentially also from coastal regions, tundra, and biomass burning. Via accumulation of secondary organic aerosol (SOA), a significant fraction of the new particles grow to sizes that are active in cloud droplet formation. Although the gaseous precursors to Arctic marine SOA remain poorly defined, the measured levels of common continental SOA precursors (isoprene and monoterpenes) were low, whereas elevated mixing ratios of oxygenated volatile organic compounds (OVOCs) were inferred to arise via processes involving the sea surface microlayer. (3) The variability in the vertical distribution of black carbon (BC) under both springtime Arctic haze and more pristine summertime aerosol conditions was observed. Measured particle size distributions and mixing states were used to constrain, for the first time, calculations of aerosol–climate interactions under Arctic conditions. Aircraft- and ground-based measurements were used to better establish the BC source regions that supply the Arctic via long-range transport mechanisms, with evidence for a dominant springtime contribution from eastern and southern Asia to the middle troposphere, and a major contribution from northern Asia to the surface. (4) Measurements of ice nucleating particles (INPs) in the Arctic indicate that a major source of these particles is mineral dust, likely derived from local sources in the summer and long-range transport in the spring. In addition, INPs are abundant in the sea surface microlayer in the Arctic, and possibly play a role in ice nucleation in the atmosphere when mineral dust concentrations are low. (5) Amongst multiple aerosol components, BC was observed to have the smallest effective deposition velocities to high Arctic snow (0.03 cm s−1).

Published
2019
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3. The effect of (NH4)2SO4 on the freezing properties of non-mineral dust ice-nucleating substances of atmospheric relevance

Author

Yu Xi, Soleil E. Worthy, Victoria E. Irish, Jessie Chen, Pierre Amato, Allan K. Bertram, Anand Kumar, Cuishan Xu, Jingwei Yun, STMicroelectronics [India] (ST-INDIA), Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Institut de Chimie de Clermont-Ferrand (ICCF), and SIGMA Clermont (SIGMA Clermont)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Chemistry, Indoor bioaerosol, Nucleation, Mineral dust, 010402 general chemistry, 01 natural sciences, Sea surface microlayer, complex mixtures, 0104 chemical sciences, Atmosphere, 13. Climate action, Environmental chemistry, [SDE]Environmental Sciences, Sea ice, Ice nucleus, Kaolinite, 0105 earth and related environmental sciences
Abstract

A wide range of materials including mineral dust, soil dust, and bioaerosols have been shown to act as ice nuclei in the atmosphere. During atmospheric transport, these materials can become coated with inorganic and organic solutes which may impact their ability to nucleate ice. While a number of studies have investigated the impact of solutes at low concentrations on ice nucleation by mineral dusts, very few studies have examined their impact on non-mineral dust ice nuclei. We studied the effect of dilute (NH4)2SO4 solutions (0.05 M) on immersion freezing of a variety of non-mineral dust ice-nucleating substances (INSs) including bacteria, fungi, sea ice diatom exudates, sea surface microlayer substances, and humic substances using the droplet-freezing technique. We also studied the effect of (NH4)2SO4 solutions (0.05 M) on the immersion freezing of several types of mineral dust particles for comparison purposes. (NH4)2SO4 had no effect on the median freezing temperature (ΔT50) of 9 of the 10 non-mineral dust materials tested. There was a small but statistically significant decrease in ΔT50 (−0.43 ± 0.19 ∘C) for the bacteria Xanthomonas campestris in the presence of (NH4)2SO4 compared to pure water. Conversely, (NH4)2SO4 increased the median freezing temperature of four different mineral dusts (potassium-rich feldspar, Arizona Test Dust, kaolinite, montmorillonite) by 3 to 9 ∘C and increased the ice nucleation active site density per gram of material (nm(T)) by a factor of ∼ 10 to ∼ 30. This significant difference in the response of mineral dust and non-mineral dust ice-nucleating substances when exposed to (NH4)2SO4 suggests that they nucleate ice and/or interact with (NH4)2SO4 via different mechanisms. This difference suggests that the relative importance of mineral dust to non-mineral dust particles for ice nucleation in mixed-phase clouds could potentially increase as these particles become coated with (NH4)2SO4 in the atmosphere. This difference also suggests that the addition of (NH4)2SO4 (0.05 M) to atmospheric samples of unknown composition could potentially be used as an indicator or assay for the presence of mineral dust ice nuclei, although additional studies are still needed as a function of INS concentration to confirm the same trends are observed for different INS concentrations than those used here. A comparison with results in the literature does suggest that our results may be applicable to a range of mineral dust and non-mineral dust INS concentrations.

Published
2021
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4. 31 P Chemical Shifts in Ru(II) Phosphine Complexes. A Computational Study of the Influence of the Coordination Sphere

Author

Christophe Raynaud, Odile Eisenstein, Eliott Norbert-Agaisse, Brian R. James, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Hylleraas Centre for Quantum Molecular Sciences (Hylleraas), Department of Chemistry [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences [Oslo], and University of Oslo (UiO)-University of Oslo (UiO)

Subjects
Denticity, Coordination sphere, 010405 organic chemistry, Chemistry, Ligand, Chemical shift, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Inorganic Chemistry, Bond length, Chemical species, Crystallography, Density functional theory, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Natural bond orbital
Abstract

International audience; NMR chemical shift has been the most versatile marker of chemical structures, by reflecting global and local electronic structures, and is very sensitive to any change within the chemical species. In this work, a set of Ru(II) complexes with the same five ligands and a variable 6 th ligand L (none, H2O, H2S, CH3SH, H2, N2, N2O, NO + , C=CHPh, and CO) is studied, using as the NMR reporter, the phosphorus PA of a coordinated bidentate PAN ligand (PAN = o-diphenylphosphino-N,N'dimethylaniline). The chemical shift of PA in RuCl2(PAN)(PR3)(L) (R = phenyl, p-tolyl or p-FC6H4) was shown to increase as the RuPA bond distance decreases, an observation that was not rationalized. This work, using density functional theory (DFT) calculations, reproduces reasonably well the observed 31 P chemical shifts for these complexes, and the correlation between the shifts and the RuPA bond distance as L varies. An interpretation of this correlation is proposed using a Natural Chemical Shift (NCS) analysis based on the Natural Bonding Orbital (NBO) method. This analysis of the principal components of the chemical shift tensors shows how the s-donating properties of L have a particularly high influence on the phosphine chemical shifts.

Published
2020
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5. Sawfly Genomes Reveal Evolutionary Acquisitions That Fostered the Mega-Radiation of Parasitoid and Eusocial Hymenoptera

Author

Sebastian Martin, Huyen Dinh, Kim C. Worley, Björn M. von Reumont, Tanja Ziesmann, Elena N. Elpidina, Cameron Gudobba, Alexander G. Martynov, Patrice Baa-Puyoulet, Cornelis J. P. Grimmelikhuijzen, Elizabeth Cash, Olivia R.A. Tidswell, Federica Calevro, Aaron Stahl, Markus Friedrich, Jiaxin Qu, Andrew J. Rosendale, Joshua B. Benoit, Leo W. Beukeboom, Shwetha C. Murali, Mackenzie Lovegrove, Panagiotis Ioannidis, Brenda Oppert, Daniel Dowling, Mei-Ju May Chen, Peter Lesný, Elzemiek Geuverink, Jan Philip Oeyen, Bernhard Misof, Maarten J.M.F. Reijnders, Masatsugu Hatakeyama, Emily C. Jennings, Christoph Mayer, Lucia Vedder, Daisuke S. Yamamoto, Anja Buttstedt, Hsu Chao, Elizabeth J. Duncan, Louis van de Zande, Daniel S.T. Hughes, Monica Munoz-Torres, Erich Bornberg-Bauer, Richard A. Gibbs, Lars Podsiadlowski, Peter K. Dearden, Alexandros G Sotiropoulos, Ralph S. Peters, Nicolas Montagné, Jeanne Wilbrandt, Andrew G. Cridge, Stephen Richards, John H. Werren, Yi Han, Sandra L. Lee, Megumi Sumitani, Victoria C. Moris, Oliver Niehuis, Ewald Große-Wilde, Amanda Dolan, Elise M. Szuter, Nicolas Parisot, Christopher P. Childers, Emmanuelle Jacquin-Joly, Sonja Grath, Panagiotis Provataris, Donna M. Muzny, Thomas Pauli, Joshua D. Gibson, Steffen Klasberg, Frank Hauser, John Skelly, Robert M. Waterhouse, Alexander Donath, Monica F. Poelchau, Shannon Dugan, Bill S. Hansson, Hubert Charles, Harshavardhan Doddapaneni, Malte Petersen, Evgeny M. Zdobnov, Evangelos Tsitlakidis, Christian Pick, Felipe A. Simão, Emma Persyn, Jeffery W. Jones, Lavrov, Dennis, Beukeboom lab, Evolutionary Genetics, Development & Behaviour, Van de Zande lab, Biologie Fonctionnelle, Insectes et Interactions (BF2I), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Groningen Institute for Evolutionary Life Sciences [Groningen] (GELIFES), University of Groningen [Groningen], Westfälische Wilhelms-Universität Münster (WWU), Biochemistry Department, University of Otago [Dunedin, Nouvelle-Zélande], Max-Planck-Institut für Kernphysik (MPIK), Max-Planck-Gesellschaft, Max Planck Institute for Chemical Ecology, Physiologie de l'Insecte : Signalisation et Communication (PISC), Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech, Institute for Evolution and Biodiversity (IEB), Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Human Genome Sequencing Center, Baylor College of Medicine, Baylor College of Medicine (BCM), Baylor University-Baylor University, Center for Molecular Biodiversity Research (ZMB), Zoological Research Museum Alexander Koenig (ZFMK), Department of Biology, Georgetown University, Université de Lausanne (UNIL), Human Genome Sequencing Center [Houston] (HGSC), Grad Sch Life Sci, Div Neurogenet, Tohoku University [Sendai], Department of Genetic Medicine and Development [Geneva], Université de Genève (UNIGE), Zoologisches Forschungsmuseum Alexander Koenig, Center for Molecular Biodiversity Research, Lavrov, Dennis (ed.), Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris ), Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and Zdobnov, Evgeny

Subjects
AcademicSubjects/SCI01140, 0106 biological sciences, Most recent common ancestor, Male, Vision, Genome, Insect, Gene Dosage, Hymenoptera, JEWEL WASP NASONIA, Receptors, Odorant, 01 natural sciences, Genome, Parasitoid, MULTIPLE SEQUENCE ALIGNMENT, opsin, Receptors, phytophagy, ddc:576.5, Apocrita, Conserved Sequence, 0303 health sciences, [SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE], HOST LOCATION, Eusociality, ROYAL JELLY PROTEIN, ATHALIA-ROSAE, Sawfly, Odorant, APIS-MELLIFERA, Multigene Family, Insect Proteins, Female, Research Article, Genetics, Ecology, Evolution, Behavior and Systematics, hexamerin, major royal jelly protein, microsynteny, odorant receptor, CHEMORECEPTOR SUPERFAMILY, Genetic Speciation, Biology, 010603 evolutionary biology, Host-Parasite Interactions, 03 medical and health sciences, Ocular, Animals, Amino Acid Sequence, Herbivory, Social Behavior, DRAFT GENOME, Life Below Water, Vision, Ocular, 030304 developmental biology, MODEL SELECTION, Glycoproteins, Orussidae, Evolutionary Biology, fungi, Human Genome, AcademicSubjects/SCI01130, Immunity, biology.organism_classification, MOLECULAR EVOLUTION, Evolutionary biology, DNA Transposable Elements, Biochemistry and Cell Biology, Insect, [SDV.EE.IEO]Life Sciences [q-bio]/Ecology, environment/Symbiosis, Developmental Biology
Abstract

The tremendous diversity of Hymenoptera is commonly attributed to the evolution of parasitoidism in the last common ancestor of parasitoid sawflies (Orussidae) and wasp-waisted Hymenoptera (Apocrita). However, Apocrita and Orussidae differ dramatically in their species richness, indicating that the diversification of Apocrita was promoted by additional traits. These traits have remained elusive due to a paucity of sawfly genome sequences, in particular those of parasitoid sawflies. Here, we present comparative analyses of draft genomes of the primarily phytophagous sawfly Athalia rosae and the parasitoid sawfly Orussus abietinus. Our analyses revealed that the ancestral hymenopteran genome exhibited traits that were previously considered unique to eusocial Apocrita (e.g., low transposable element content and activity) and a wider gene repertoire than previously thought (e.g., genes for CO2 detection). Moreover, we discovered that Apocrita evolved a significantly larger array of odorant receptors than sawflies, which could be relevant to the remarkable diversification of Apocrita by enabling efficient detection and reliable identification of hosts.

Published
2020
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6. Physical methods for mechanistic understanding: general discussion

Author

Jonathan D. Wilden, Simone Gallarati, Jennifer A. Love, David J. Nelson, Samuel Scott, Thomas Braun, David Schilter, Matthias Bauer, Aaron L. Odom, David L. Davies, Robert H. Morris, Vidar R. Jensen, Tolga Yaman, Jana Roithova, Yutaka Aoki, Kevin R. J. Lovelock, Alexander J Hamilton, Evert Jan Meijer, Jason M. Lynam, James W. Walton, Meghan E. Halse, Alison N. Hulme, Joseph S. Renny, Youichi Ishii, Shigeki Kuwata, Robin N. Perutz, Stuart MacGregor, Aiwen Lei, Laurel L. Schafer, Jamie A. Cadge, Martin Jakoobi, John M. Slattery, Todd B. Marder, Derek J. Durand, Ian J. S. Fairlamb, Guy C. Lloyd-Jones, Pierre Kennepohl, Natalie Fey, M. George, Odile Eisenstein, Ulrich Hintermair, Anthony Haynes, Megan Greaves, Markus Reiher, Jeremy N. Harvey, Daniel H. Ess, Patrick Morgan, Joseph M. Mwansa, Tom A. Young, Chun-Yuen Wong, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Brigham Young University (BYU), Department of Chemistry [York, UK], University of York [York, UK], University of Bristol [Bristol], Department of Chemistry, University of Bergen (UiB), Medical Informatics Division, Tottori University Hospital, Heriot-Watt University [Edinburgh] (HWU), University of Würzburg, Universiteit van Amsterdam (UvA), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Department of Organic Chemistry [Prague], University of Chemistry and Technology Prague (UCT Prague), Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), and Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS) (CMCM)

Subjects
h-2, spectroscopy, 02 engineering and technology, spin states, ligand, 010402 general chemistry, 01 natural sciences, PI-SYMMETRY, ABSORPTION, Physical and Theoretical Chemistry, CARBON-MONOXIDE, ComputingMilieux_MISCELLANEOUS, SPIN STATES, H-2, Cognitive science, CATALYST, complexes, Science & Technology, SPECTROSCOPY, Chemistry, Physical, carbon-monoxide, [CHIM.CATA]Chemical Sciences/Catalysis, HYDROGEN, 021001 nanoscience & nanotechnology, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Chemistry, pi-symmetry, hydrogen, Physical Sciences, COMPLEXES, LIGAND, 0210 nano-technology, Psychology, absorption, catalyst
Abstract

ispartof: FARADAY DISCUSSIONS vol:220 issue:0 pages:144-178 ispartof: location:England status: published

Published
2019
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7. Ta-Catalyzed Hydroaminoalkylation of Alkenes: Insights into Ligand-Modified Reactivity Using DFT

Author

Damon J. Gilmour, Eric Clot, Jean Michel P. Lauzon, Laurel L. Schafer, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Laboratoire de structure et de dynamique des systèmes moléculaires et solides (LSDSMS), and Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Steric effects, 010405 organic chemistry, Ligand, Alkene, Organic Chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, Metallacycle, 010402 general chemistry, Photochemistry, 01 natural sciences, 0104 chemical sciences, Catalysis, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Inorganic Chemistry, chemistry, Electronic effect, Reactivity (chemistry), [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Protonolysis, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

Density functional theory (DFT) calculations were performed to probe the mechanism of tantalum-catalyzed hydroaminoalkylation, a reaction that affords Csp3–Csp3 bond formation via α-alkylation of a secondary amine with an alkene. Electronic effects in catalyst design were probed to reveal key features in the energy profile of the proposed mechanism, corroborating experimental trends in which electrophilic metal centers demonstrate enhanced reactivity. Modeling of the energy profile with an N,O-chelating amidate Ta catalyst (I) revealed profound differences in relative energetics, rationalizing improvements that have been observed using sterically and electronically varied ligands. N,O-Chelating ligands electronically promote preferential reactivity in the equatorial plane. The turnover-limiting step can be completely changed depending upon the ligand; for sterically bulky monoamidate complexes, the protonolysis of an intermediate metallacycle is the turnover-limiting step rather than C–H activation, as ha...

Published
2018
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8. Modeling the hydrolysis of iron–sulfur clusters

Author

Peng Zheng, Sofia R. G. Camilo, Martin J. Field, Hongbin Li, Guilherme Menegon Arantes, Felipe Curtolo, Murilo Hoias Teixeira, Department of Biochemistry, Instituto de Química, Groupe modélisation et chimie théorique (MCT ), Laboratoire de Chimie et Biologie des Métaux (LCBM - UMR 5249), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-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)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Institut Laue-Langevin (ILL), ILL, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Department of Chemistry [Vancouver] (UBC Chemistry), and University of British Columbia (UBC)

Subjects
Models, Molecular, General Chemical Engineering, Iron, Molecular Conformation, ENXOFRE, Protonation, Library and Information Sciences, 01 natural sciences, Dissociation (chemistry), Molecular dynamics, Computational chemistry, 0103 physical sciences, Nucleophilic substitution, Aqueous solution, 010304 chemical physics, Chemistry, Hydrolysis, Leaving group, Solvation, Water, General Chemistry, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, 0104 chemical sciences, Computer Science Applications, 010404 medicinal & biomolecular chemistry, Solvents, Quantum Theory, Thermodynamics, Density functional theory, Sulfur, [CHIM.CHEM]Chemical Sciences/Cheminformatics
Abstract

International audience; Iron-sulfur (FeS) clusters are essential metal cofactors involved in a wide variety of biological functions. Their catalytic efficiency, biosynthesis, and regulation depend on FeS stability in aqueous solution. Here, molecular modeling is used to investigate the hydrolysis of an oxidized (ferric) mononuclear FeS cluster by bare dissociation and water substitution mechanisms in neutral and acidic solution. First, approximate electronic structure descriptions of FeS reactions by density functional theory are validated against high-level wave function CCSD(T) calculations. Solvation contributions are included by an all-atom model with hybrid quantum chemical/molecular mechanical (QM/MM) potentials and enhanced sampling molecular dynamics simulations. The free energy profile obtained for FeS cluster hydrolysis indicates that the hybrid functional M06 together with an implicit solvent correction capture the most important aspects of FeS cluster reactivity in aqueous solution. Then, 20 reaction channels leading to two consecutive Fe-S bond ruptures were explored with this calibrated model. For all protonation states, nucleophilic substitution with concerted bond breaking and forming to iron is the preferred mechanism, both kinetic and thermodynamically. In neutral solution, proton transfer from water to the sulfur leaving group is also concerted. Dissociative reactions show higher barriers and will not be relevant for FeS reactivity when exposed to solvent. These hydrolysis mechanisms may help to explain the stability and catalytic mechanisms of FeS clusters of multiple sizes and proteins.

Published
2020
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9. Straightforward convergent access to 2-arylated polysubstituted benzothiazoles

Author

Emmanuel Gras, David M. Perrin, Omar Sadek, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Institut des Technologies Avancées en sciences du Vivant (ITAV), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université Toulouse III-Paul Sabatier, French Canadian Research Fund, Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010405 organic chemistry, Organic Chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, Combinatorial chemistry, 0104 chemical sciences, chemistry.chemical_compound, Benzothiazole, chemistry, Drug Discovery, Physical organic chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Reactivity (chemistry)
Abstract

International audience; A modular access to 2,4 disubstituted benzothiazoles has been achieved though the intermediacy of 4-bromo-2-iodobenzothiazole. The difference in reactivity of both halogens was advantageously exploited to achieve sequential Suzuki-Miyaura cross-coupling giving access to a range of polyaromatic derivatives featuring a central benzothiazole core.

Published
2019
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10. Mechanistic insight into organic and industrial transformations: general discussion

Author

Joseph S. Renny, Alison N. Hulme, James W. Walton, Markus Reiher, Jeremy N. Harvey, Aaron L. Odom, Jason M. Lynam, Odile Eisenstein, Shigeki Kuwata, Jana Roithova, Martin Jakoobi, George E Clarke, Robin N. Perutz, Anthony Haynes, Laurel L. Schafer, David J. Nelson, Stuart MacGregor, Matthias Bauer, Youichi Ishii, Yutaka Aoki, Toshiro Takao, Peter W. Seavill, Thomas Braun, Simone Gallarati, Megan Greaves, Guy C. Lloyd-Jones, Jennifer A. Love, Tom A. Young, Jamie A. Cadge, John M. Slattery, Jonathan D. Wilden, Chun-Yuen Wong, Pierre Kennepohl, Aiwen Lei, Derek J. Durand, Samuel Scott, Robert H. Morris, Vidar R. Jensen, Ulrich Hintermair, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), University of Bergen (UiB), Medical Informatics Division, Tottori University Hospital, Heriot-Watt University [Edinburgh] (HWU), Department of Chemistry [York, UK], University of York [York, UK], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Department of Organic Chemistry [Prague], University of Chemistry and Technology Prague (UCT Prague), Department of Chemistry [Vancouver] (UBC Chemistry), and University of British Columbia (UBC)

Subjects
ab-initio, mono-oxidation, complexes, ligands, 010405 organic chemistry, Chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, reactivity, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, phosphines, challenge, Spectroscopy and Catalysis, donor properties, activation, Biochemical engineering, solvation, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

Contains fulltext : 215022.pdf (Publisher’s version ) (Open Access)

Published
2019
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11. Computational and theoretical approaches for mechanistic understanding: general discussion

Author

Alison N. Hulme, Matthias Bauer, Aaron L. Odom, Natalie Fey, Robin N. Perutz, Markus Reiher, Robert H. Morris, Vidar R. Jensen, Jeremy N. Harvey, Daniel H. Ess, Odile Eisenstein, Todd B. Marder, Patrick Morgan, Jamie A. Cadge, John M. Slattery, Alexander J Hamilton, Guy C. Lloyd-Jones, Evert Jan Meijer, Youichi Ishii, Ulrich Hintermair, Stuart MacGregor, Simone Gallarati, Jennifer A. Love, Laurel L. Schafer, David L. Davies, Derek J. Durand, Joseph M. Mwansa, Tom A. Young, Jason M. Lynam, M. George, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Brigham Young University (BYU), University of Bristol [Bristol], University of Bergen (UiB), Heriot-Watt University [Edinburgh] (HWU), University of Würzburg, Universiteit van Amsterdam (UvA), Department of Chemistry [York, UK], University of York [York, UK], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Department of Chemistry [Vancouver] (UBC Chemistry), and University of British Columbia (UBC)

Subjects
Science & Technology, 010405 organic chemistry, Computer science, Management science, Chemistry, Physical, boronic acid, C-H ACTIVATION, BORONIC ACID, c-h activation, [CHIM.CATA]Chemical Sciences/Catalysis, BASE, exploration, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, EXPLORATION, Chemistry, MOLECULES, Physical Sciences, [CHIM]Chemical Sciences, molecules, base, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

ispartof: FARADAY DISCUSSIONS vol:220 issue:0 pages:464-488 ispartof: location:England status: published

Published
2019
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12. Preliminary results from the FARCE 2015 campaign: multidisciplinary study of the forest–gas–aerosol–cloud system on the tropical island of La Réunion

Author

Duflot, Valentin, Tulet, Pierre, Flores, Olivier, Barthe, Christelle, Colomb, Aurélie, Deguillaume, Laurent, Vaitilingom, Mickaël, Perring, Anne, Huffman, Alex, Hernandez, Mark, Sellegri, Karine, Robinson, Ellis, O'Connor, David, Gomez, Odessa, Burnet, Frédéric, Bourrianne, Thierry, Strasberg, Dominique, Rocco, Manon, Bertram, Allan, Chazette, Patrick, Totems, Julien, Fournel, Jacques, Stamenoff, Pierre, Metzger, Jean-Marc, Chabasset, Mathilde, Rousseau, Clothilde, Bourrianne, Eric, Sancelme, Martine, Delort, Anne-Marie, Wegener, Rachel, Chou, Cedric, Elizondo, Pablo, Laboratoire de l'Atmosphère et des Cyclones (LACy), Météo France-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Peuplements végétaux et bioagresseurs en milieu tropical (UMR PVBMT), Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de La Réunion (UR)-Institut National de la Recherche Agronomique (INRA), Laboratoire de météorologie physique (LaMP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Synthèse et étude de systèmes à intêret biologique (SEESIB), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Physique - Clermont Auvergne (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), University of Wisconsin-Madison, Centre national de recherches météorologiques (CNRM), Météo France-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Vancouver], University of British Columbia (UBC), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Sigma CLERMONT (Sigma CLERMONT), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université de La Réunion (UR), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Vancouver] (UBC Chemistry), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Chimie Atmosphérique Expérimentale (CAE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), SIGMA Clermont (SIGMA Clermont), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Météo France, Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience; The Forests gAses aeRosols Clouds Exploratory (FARCE) campaign was conducted in March-April 2015 on the tropical island of La Réunion. For the first time, several scientific teams from different disciplines collaborated to provide reference measurements and characterization of La Réunion vegetation, volatile organic compounds (VOCs), biogenic VOCs (BVOCs), (bio)aerosols and composition of clouds, with a strong focus on the Maïdo mountain slope area. The main observations obtained during this 2-month intensive field campaign are summarized. They include characterizations of forest structure, concentrations of VOCs and precursors emitted by forests, aerosol loading and optical properties in the planetary boundary layer (PBL), formation of new particles by nucleation of gas-phase precursors, ice-nucleating particles concentrations, and biological loading in both cloud-free and cloudy conditions. Simulations and measurements confirm that the Maïdo Observatory lies within the PBL from late morning to late evening and that, when in the PBL, the main primary sources impacting the Maïdo Observatory are of marine origin via the Indian Ocean and of bio-genic origin through the dense forest cover. They also show that (i) the marine source prevails less and less while reaching the observatory; (ii) when in the PBL, depending on the lo-calization of a horizontal wind shear, the Maïdo Observatory can be affected by air masses coming directly from the ocean and passing over the Maïdo mountain slope, or coming from inland; (iii) bio-aerosols can be observed in both cloud-free and cloudy conditions at the Maïdo Observatory; (iv) BVOC emissions by the forest covering the Maïdo mountain slope can be transported upslope within clouds and are a potential cause of secondary organic aerosol formation in the aqueous phase at the Maïdo Observatory; and (v) the simulation of dynamics parameters, emitted BVOCs and cloud life cycle in the Meso-NH model are realistic, and more advanced Meso-NH simulations should use an increased horizontal resolution (100 m) to better take into account the orography and improve the simulation of the wind shear front zone within which lies the Maïdo Observatory. Using various observations and simulations, this work draws up an inventory of the in situ studies that could be performed in La Réunion and at the Maïdo Observatory. It also aims to develop scientific collaborations and to support future scientific projects in order to better understand the forest-gas-aerosol-cloud system in an insular tropical environment.

Published
2019
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13. Unsymmetrical diaryliodonium phenyltrifluoroborate salts: Synthesis, structure and fluorination

Author

Omar Sadek, David M. Perrin, Emmanuel Gras, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut des Technologies Avancées en sciences du Vivant (ITAV), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université Paul Sabatier, and French Canadian Research Fund

Subjects
Organotrifluoroborate, 010405 organic chemistry, Aryl, Organic Chemistry, Fluoride products, Crystal structure, 010402 general chemistry, 01 natural sciences, Biochemistry, Combinatorial chemistry, 0104 chemical sciences, Diaryliodonium, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Fluorination, Preliminary report, Environmental Chemistry, Reactivity (chemistry), [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Fluorinated arenes
Abstract

International audience; The unprecedented reaction of organotrifluoroborates salts of unsymmetrical diaryliodoniums to give aryl fluorides is presented. This preliminary report describes the first synthesis of unsymmetrical diaryliodonium phenyltrifluoroborates along with an exemplary x-ray crystal structure, and explores their reactivity regarding the fluorination of the diaryliodonium cation. Fluorination was found to be chemoselective, providing exclusively hindered aryl fluoride products in moderate to good yields (up to 89%).

Published
2019
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14. Ice nucleating particles in the marine boundary layer in the Canadian Arctic during summer 2014

Author

V. E. Irish, S. J. Hanna, M. D. Willis, S. China, J. L. Thomas, J. J. B. Wentzell, A. Cirisan, M. Si, W. R. Leaitch, J. G. Murphy, J. P. D. Abbatt, A. Laskin, E. Girard, A. K. Bertram, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Department of Chemistry [University of Toronto], University of Toronto, William R. Wiley Environmental Molecular Sciences Laboratory (EMSL), Pacific Northwest National Laboratory (PNNL), Institut des Géosciences de l’Environnement (IGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Recherche pour le Développement (IRD)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Air Quality Research Division [Toronto], Environment and Climate Change Canada, Département des sciences de la terre et de l'atmosphère [Montréal] (SCTA), Université du Québec à Montréal = University of Québec in Montréal (UQAM), Climate Research Division [Toronto], Department of Chemistry [West Lafayette], Purdue University [West Lafayette], Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Atmospheric Science, education.field_of_study, 010504 meteorology & atmospheric sciences, Population, 010501 environmental sciences, Mineral dust, Atmospheric dispersion modeling, Sea spray, Atmospheric sciences, 01 natural sciences, lcsh:QC1-999, Aerosol, lcsh:Chemistry, Arctic, lcsh:QD1-999, 13. Climate action, Environmental science, Precipitation, education, Air mass, lcsh:Physics, 0105 earth and related environmental sciences
Abstract

Ice nucleating particles (INPs) in the Arctic can influence climate and precipitation in the region; yet our understanding of the concentrations and sources of INPs in this region remain uncertain. In the following, we (1) measured concentrations of INPs in the immersion mode in the Canadian Arctic marine boundary layer during summer 2014 on board the CCGS Amundsen, (2) determined ratios of surface areas of mineral dust aerosol to sea spray aerosol, and (3) investigated the source region of the INPs using particle dispersion modelling. Average concentrations of INPs at −15, −20, and −25 ∘C were 0.005, 0.044, and 0.154 L−1, respectively. These concentrations fall within the range of INP concentrations measured in other marine environments. For the samples investigated the ratio of mineral dust surface area to sea spray surface area ranged from 0.03 to 0.09. Based on these ratios and the ice active surface site densities of mineral dust and sea spray aerosol determined in previous laboratory studies, our results suggest that mineral dust is a more important contributor to the INP population than sea spray aerosol for the samples analysed. Based on particle dispersion modelling, the highest concentrations of INPs were often associated with lower-latitude source regions such as the Hudson Bay area, eastern Greenland, or north-western continental Canada. On the other hand, the lowest concentrations were often associated with regions further north of the sampling sites and over Baffin Bay. A weak correlation was observed between INP concentrations and the time the air mass spent over bare land, and a weak negative correlation was observed between INP concentrations and the time the air mass spent over ice and open water. These combined results suggest that mineral dust from local sources is an important contributor to the INP population in the Canadian Arctic marine boundary layer during summer 2014.

Published
2019
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15. Expanding the Balz-Schiemann Reaction: Organotrifluoroborates Serve as Competent Sources of Fluoride Ion for Fluoro-Dediazoniation

Author

Omar Sadek, Tharwat Mohy El Dine, David M. Perrin, Emmanuel Gras, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
chemistry.chemical_classification, Steric effects, 010405 organic chemistry, Aryl, Organic Chemistry, Salt (chemistry), chemistry.chemical_element, General Chemistry, 010402 general chemistry, 01 natural sciences, Combinatorial chemistry, Catalysis, 0104 chemical sciences, Ion, chemistry.chemical_compound, chemistry, Organotrifluoroborate, Fluorine, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Balz–Schiemann reaction, Fluoride
Abstract

International audience; Abstract The Balz–Schiemann reaction endures as a method for the preparation of (hetero)aryl fluorides yet is eschewed due to the need for harsh conditions or high temperatures along with the need to isolate potentially explosive diazonium salts. In a departure from these conditions, we show that various organotrifluoroborates (RBF3−s) may serve as fluoride ion sources for solution-phase fluoro-dediazoniation in organic solvents under mild conditions. This methodology was successfully extended to a one-pot process obviating aryl diazonium salt isolation. Sterically hindered (hetero)anilines are fluorinated under unprecedentedly mild conditions in good-to-excellent yields. Taken together, this work expands the repertoire of RBF3−s to act as fluorine ion sources in an update to the classic Balz–Schiemann reaction.

Published
2018
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16. New insights into aerosol and climate in the Arctic

Author

Abbatt, Jonathan P. D., Leaitch, W. Richard, Aliabadi, Amir A., Bertram, Alan K., Blanchet, Jean-Pierre, Boivin-Rioux, Aude, Bozem, Heiko, Burkart, Julia, Chang, Rachel Y. W., Charette, Joannie, Chaubey, Jai P., Christensen, Robert J., Cirisan, Ana, Collins, Douglas B., Croft, Betty, Dionne, Joelle, Evans, Greg J., Fletcher, Christopher G., Ghahremaninezhad, Roghayeh, Girard, Eric, Gong, Wanmin, Gosselin, Michel, Gourdal, Margaux, Hanna, Sarah J., Hayashida, Hakase, Herber, Andreas B., Hesaraki, Sareh, Hoor, Peter, Huang, Lin, Hussherr, Rachel, Irish, Victoria E., Keita, Setigui A., Kodros, John K., Köllner, Franziska, Kolonjari, Felicia, Kunkel, Daniel, Ladino, Luis A., Law, Kathy S., Levasseur, Maurice, Libois, Quentin, Liggio, John, Lizotte, Martine, Macdonald, Katrina M., Mahmood, Rashed, Martin, Randall V., Mason, Ryan H., Miller, Lisa A., Moravek, Alexander, Mortenson, Eric, Mungall, Emma L., Murphy, Jennifer G., Namazi, Maryam, Norman, Ann-Lise, O'Neill, Norman T., Pierce, Jeffrey R., Russell, Lynn M., Schneider, Johannes, Schulz, Hannes, Sharma, Sangeeta, Si, Meng, Staebler, Ralf M., Steiner, Nadja S., Gali, Marti, Thomas, Jennie L., von Salzen, Knut, Wentzell, Jeremy J. B., Willis, Megan D., Wentworth, Gregory R., Xu, Jun-Wei, Yakobi-Hancock, Jacqueline D., Department of Chemistry [University of Toronto], University of Toronto, Environment and Climate Change Canada, School of Engineering [Guelph], University of Guelph, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Département des sciences de la terre et de l'atmosphère [Montréal] (SCTA), Université du Québec à Montréal = University of Québec in Montréal (UQAM), Institut des Sciences de la MER de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Institute for Atmospheric Physics [Mainz] (IPA), Johannes Gutenberg - Universität Mainz (JGU), Aerosol Physics and Environmental Physics [Vienna], University of Vienna [Vienna], Department of Physics and Atmospheric Science [Halifax], Dalhousie University [Halifax], Department of Chemistry [Lewisburg], Bucknell University, Department of Chemical Engineering and Applied Chemistry (CHEM ENG), Department of Geography and Environmental Management [Waterloo], University of Waterloo [Waterloo], Departement de Biologie [Québec], Université Laval [Québec] (ULaval), School of Earth and Ocean Sciences [Victoria] (SEOS), University of Victoria [Canada] (UVIC), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Centre d'Applications et de Recherches en TELédétection (CARTEL), Université de Sherbrooke [Sherbrooke], Department of Atmospheric Science [Fort Collins], Colorado State University [Fort Collins] (CSU), Particle Chemistry Department [Mainz], Max Planck Institute for Chemistry (MPIC), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Centro de Ciencias de la Atmosfera [Mexico], Universidad Nacional Autónoma de México (UNAM), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Biology [Québec], Air Quality Processes Research Section, Canadian Centre for Climate Modelling and Analysis (CCCma), Institute of Ocean Sciences [Sidney] (IOS), Fisheries and Oceans Canada (DFO), Department of Mathematics [Isfahan], University of Isfahan, Department of Physics and Astronomy [Calgary], University of Calgary, Scripps Institution of Oceanography (SIO), University of California [San Diego] (UC San Diego), University of California-University of California, Lawrence Berkeley National Laboratory [Berkeley] (LBNL), and National Research Council of Canada (NRC)

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology
Abstract

International audience; Motivated by the need to predict how the Arctic atmosphere will change in a warming world, this article summarizes recent advances made by the research consortium NETCARE (Network on Climate and Aerosols: Addressing Key Uncertainties in Remote Canadian Environments) that contribute to our fundamental understanding of Arctic aerosol particles as they relate to climate forcing. The overall goal of NETCARE research has been to use an interdisciplinary approach encompassing extensive field observations and a range of chemical transport, earth system, and biogeochemical models. Several major findings and advances have emerged from NETCARE since its formation in 2013 . (1) Unexpectedly high summertime dimethyl sulfide (DMS) levels were identified in ocean water and the overlying atmosphere in the Canadian Arctic Archipelago (CAA). Furthermore, melt ponds, which are widely prevalent, were identified as an important DMS source. (2) Evidence was found of widespread particle nucleation and growth in the marine boundary layer in the CAA in the summertime. DMS-oxidation-driven nucleation is facilitated by the presence of atmospheric ammonia arising from sea bird colony emissions, and potentially also from coastal regions, tundra, and biomass burning. Via accumulation of secondary organic material (SOA), a significant fraction of the new particles grow to sizes that are active in cloud droplet formation. Although the gaseous precursors to Arctic marine SOA remain poorly defined, the measured levels of common continental SOA precursors (isoprene and monoterpenes) were low, whereas elevated mixing ratios of oxygenated volatile organic compounds were inferred to arise via processes involving the sea surface microlayer. (3) The variability in the vertical distribution of black carbon (BC) under both springtime Arctic haze and more pristine summertime aerosol conditions was observed. Measured particle size distributions and mixing states were used to constrain, for the first time, calculations of aerosol–climate interactions under Arctic conditions. Aircraft- and ground-based measurements were used to better establish the BC source regions that supply the Arctic via long-range transport mechanisms. (4) Measurements of ice nucleating particles (INPs) in the Arctic indicate that a major source of these particles is mineral dust, likely derived from local sources in the summer and long-range transport in the spring. In addition, INPs are abundant in the sea surface microlayer in the Arctic, and possibly play a role in ice nucleation in the atmosphere when mineral dust concentrations are low. (5) Amongst multiple aerosol components, BC was observed to have the smallest effective deposition velocities to high Arctic snow.

Published
2018

17. The Podospora anserina lytic polysaccharide monooxygenase PaLPMO9H catalyzes oxidative cleavage of diverse plant cell wall matrix glycans

Author

Jean-Guy Berrin, Harry Brumer, Mathieu Fanuel, Sona Garajova, Nicholas McGregor, David Ropartz, Hélène Rogniaux, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Biodiversité et Biotechnologie Fongiques (BBF), Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM), Michael Smith Laboratories, University of British Columbia (UBC), Department of Chemistry [Vancouver] (UBC Chemistry), Department of Biochemistry, Department of Botany [Vancouver] (UBC Botany), AMIDEX foundation (Funcopper project) A*M-AAP-EI-13-13-130115-15.37 / MicrobioE project ANR-11-IDEX-0001-02, École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Department of Chemistry [Vancouver], Department of Botany, and Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA)-École Centrale de Marseille (ECM)

Subjects
0106 biological sciences, 0301 basic medicine, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, mass spectrum analysis, matrice extracellulaire, Glucomannan, Biotechnologies, Management, Monitoring, Policy and Law, tyrosinase, Polysaccharide, Cleavage (embryo), 01 natural sciences, Applied Microbiology and Biotechnology, Podospora anserina, Cell wall, 03 medical and health sciences, chemistry.chemical_compound, métabolisme oxydatif, lignocellulose, podospora anserina, Polysaccharides, AA9, spectrométrie de masse, 010608 biotechnology, biomasse, Biomass, LPMO, Cellulose, 2. Zero hunger, chemistry.chemical_classification, biology, Mass spectrometry, Renewable Energy, Sustainability and the Environment, Glycosidic bond, biology.organism_classification, Biorefinery, Xyloglucan, 030104 developmental biology, General Energy, chemistry, Biochemistry, polysaccharide, Lignocellulose, Biotechnology, oxydoréductase
Abstract

The enzymatic conversion of plant biomass has been recently revolutionized by the discovery of lytic polysaccharide monooxygenases (LPMO) that catalyze oxidative cleavage of polysaccharides. These powerful enzymes are secreted by a large number of fungal saprotrophs and are important components of commercial enzyme cocktails used for industrial biomass conversion. Among the 33 AA9 LPMOs encoded by the genome of Podospora anserina, the PaLPMO9H enzyme catalyzes mixed C1/C4 oxidative cleavage of cellulose and cello-oligosaccharides. Activity of PaLPMO9H on several hemicelluloses has been suggested, but the regioselectivity of the cleavage remained to be determined. In this study, we investigated the activity of PaLPMO9H on mixed-linkage glucans, xyloglucan and glucomannan using tandem mass spectrometry and ion mobility–mass spectrometry. Structural analysis of the released products revealed that PaLPMO9H catalyzes C4 oxidative cleavage of mixed-linkage glucans and mixed C1/C4 oxidative cleavage of glucomannan and xyloglucan. Gem-diols and ketones were produced at the non-reducing end, while aldonic acids were produced at the reducing extremity of the products. The ability of PaLPMO9H to target polysaccharides, differing from cellulose by their linkages, glycosidic composition and/or presence of sidechains, could be advantageous for this coprophilous fungus when catabolizing highly variable polysaccharides and for the development of optimized enzyme cocktails in biorefineries.

Published
2017
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18. [18F]-Fluoride Capture and Release : azeotropic drying free nucleophilic aromatic radiofluorination assisted by a Phosphonium Borane

Author

François P. Gabbaï, Béatrice Mestre-Voegtlé, Daniel Pla, Kantapat Chansaenpak, Sébastien Schmitt, Cécile Perrio, Emmanuel Gras, Laboratoire de Développements Méthodologiques en Tomographie par Emission de Positions ( LDM-TEP ), Imagerie et Stratégies Thérapeutiques des pathologies Cérébrales et Tumorales ( ISTCT ), Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de chimie de coordination ( LCC ), Centre National de la Recherche Scientifique ( CNRS ), Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA., University of Texas, Laboratoire de Développements Méthodologiques en Tomographie par Emission de Positons (LDM-TEP), Service Hospitalier Frédéric Joliot (SHFJ), 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 Paris-Saclay-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 Paris-Saclay-Imagerie et Stratégies Thérapeutiques des pathologies Cérébrales et Tumorales (ISTCT), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Service de Génétique, Centre hospitalier universitaire de Nantes (CHU Nantes), Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique (SPCMIB), Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Laboratoire de chimie de coordination (LCC), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Université Paris-Saclay-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)-Imagerie et Stratégies Thérapeutiques des pathologies Cérébrales et Tumorales (ISTCT), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Aqueous solution, 010405 organic chemistry, Elution, Radiosynthesis, Metals and Alloys, General Chemistry, Borane, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry.chemical_compound, chemistry, Nucleophile, Materials Chemistry, Ceramics and Composites, Nucleophilic substitution, Organic chemistry, [CHIM]Chemical Sciences, Phosphonium, Acetonitrile, [CHIM.RADIO]Chemical Sciences/Radiochemistry, [ CHIM.RADIO ] Chemical Sciences/Radiochemistry
Abstract

International audience; [18F]-Fluoride ready for aromatic nucleophilic substitution was prepared according to a simple process including trapping of aqueous [18F]-fluoride on a cartridge pre-loaded with the phosphonium borane [(Ph2MeP)C6H4(BMes2)]+, then releasing by elution of TBACN in dry acetonitrile. Subsequent radiofluorination was successfully applied to a model reaction and to the radiosynthesis of [18F]-setoperone.

Published
2016
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19. A Metabolic Gene Cluster in the Wheat W1 and the Barley Cer-cqu Loci Determines β-Diketone Biosynthesis and Glaucousness

Author

Gil Ben-Zvi, Asaph Aharoni, Hélène Bergès, Matan Levy, Gilgi Friedlander, Reinhard Jetter, Elena Kartvelishvily, Radu C. Racovita, Wing Sham Lee, Noam Alkan, Kostya Kanyuka, Efrat Almekias-Siegl, Cristobal Uauy, Shelly Hen-Avivi, Assaf Distelfeld, Sergey Malitsky, Nikolai M. Adamski, Sonia Vautrin, Orna Savin, Department of Plant and Environmental Sciences, Weizmann Institute of Science [Rehovot, Israël], Tel Aviv University [Tel Aviv], Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Rothamsted Research, John Innes Centre, Centre National de Ressources Génomiques Végétales (CNRGV), Institut National de la Recherche Agronomique (INRA), Agricultural Research Organization, Department of Botany, Israel Science Foundation (ISF) personal grant [646/11], European Research Council (SAMIT-FP7 program), Natural Sciences and Engineering Research Council Discovery Grant (Canada) [2208738], Canada Foundation for Innovation Grant [201681], and UK Biotechnology and Biological Sciences Research Council [BB/J004588/1, BB/H018824/1, BB/J00426X/1]

Subjects
0106 biological sciences, 0301 basic medicine, [SDV]Life Sciences [q-bio], Mutant, Locus (genetics), Plant Science, Biology, 01 natural sciences, 03 medical and health sciences, Gene Expression Regulation, Plant, Gene cluster, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, Gene Silencing, Gene, Research Articles, Triticum, Plant Proteins, 2. Zero hunger, Regulation of gene expression, Genetics, food and beverages, Hordeum, Cell Biology, Ketones, biology.organism_classification, Tetraploidy, 030104 developmental biology, Multigene Family, lipids (amino acids, peptides, and proteins), Hordeum vulgare, Heterologous expression, 010606 plant biology & botany
Abstract

International audience; The glaucous appearance of wheat (Triticum aestivum) and barley (Hordeum vulgare) plants, that is the light bluish-gray look of flag leaf, stem, and spike surfaces, results from deposition of cuticular beta-diketone wax on their surfaces; this phenotype is associated with high yield, especially under drought conditions. Despite extensive genetic and biochemical characterization, the molecular genetic basis underlying the biosynthesis of beta-diketones remains unclear. Here, we discovered that the wheat W1 locus contains a metabolic gene cluster mediating beta-diketone biosynthesis. The cluster comprises genes encoding proteins of several families including type-III polyketide synthases, hydrolases, and cytochrome P450s related to known fatty acid hydroxylases. The cluster region was identified in both genetic and physical maps of glaucous and glossy tetraploid wheat, demonstrating entirely different haplotypes in these accessions. Complementary evidence obtained through gene silencing in planta and heterologous expression in bacteria supports a model for a b-diketone biosynthesis pathway involving members of these three protein families. Mutations in homologous genes were identified in the barley eceriferum mutants defective in b-diketone biosynthesis, demonstrating a gene cluster also in the b-diketone biosynthesis Cer-cqu locus in barley. Hence, our findings open new opportunities to breed major cereal crops for surface features that impact yield and stress response.

Published
2016
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20. Naphthylaminoborane: from structural switches to frustrated Lewis pair reactivity

Author

Sarah Cadet, Daniel Pla, Emmanuel Gras, Omar Sadek, Béatrice Mestre-Voegtlé, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA), Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Centre National de la Recherche Scientifique (CNRS), Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique (SPCMIB), Department of Chemistry [Vancouver] (UBC Chemistry), and University of British Columbia (UBC)

Subjects
Molecular switch, Steric effects, Stereochemistry, Acenaphthene, chemistry.chemical_element, Electron, Frustrated Lewis pair, Inorganic Chemistry, Crystallography, chemistry.chemical_compound, chemistry, [CHIM]Chemical Sciences, Moiety, Molecular orbital, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Boron, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; A series of naphthyl-bridged amino-borane derivatives, namely 1-(dimethylamino)-8-naphthylboranes (1, 3, 5, 7) and 5-(dimethylamino)-6-acenaphthylboranes (2, 4, 6, 8, 10, 11), differing in the steric and electronic properties of the boryl moiety, have been synthesized and fully characterized by spectroscopic and crystallographic means. Structural X-ray analysis of the peri-atom displacement and ring torsion angles served to experimentally assess the presence and magnitude of the B-N interactions. The reversible quaternarization of nitrogen has been explored and was found to provide an efficient switch corresponding to different molecular organizations. The electronic characteristics of the nature of B-N interactions were further studied by Natural Bonding Orbital analysis derived from the theoretically calculated electron densities. This real-space bonding indicator discriminates the bonding B-N contact in 5 from the nonbonding in 8, which correlates with the flexibility of the naphthyl scaffold to respond to the Lewis acidity of boron allowing shorter peri interactions. Whereas, the steric shielding imposed by the two mesityl groups, and/or the rigidity of the acenaphthene framework disrupt B-N interaction. Thus, this communication reports on the modulation of the B-N bonding continuum by means of structural tuning leading to a molecular switch, as well as its implications towards revealing FLP reactivities through the isolation of intermediates of a stepwise mechanism.

Published
2015
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21. Density Functional Study of Spin State in CpM(NO)X2 (M = Mo, Cr; X = Cl, NH2, CH3): Spectrochemical and Nephelauxetic Effects in Organometallic Compounds1

Author

Peter Legzdins, Kevin M. Smith, and W. Stephen McNeil, Rinaldo Poli, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Laboratoire de Synthèse et Electrosynthèse Organométalliques (LSEO), and Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)

Subjects
Spin states, Electrical energy, Ligands, 010402 general chemistry, Quantum mechanics, 01 natural sciences, Dissociation (chemistry), Inorganic Chemistry, Paramagnetism, chemistry.chemical_compound, Mathematical methods, Computational chemistry, Amide, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Singlet state, Physical and Theoretical Chemistry, 010405 organic chemistry, Chemistry, Organic Chemistry, Amides, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Bond length, Crystallography, Diamagnetism, Electron configuration
Abstract

International audience; The relationship between spin state and metal−ligand bonding interactions in CpM(NO)X2 species was investigated using density functional computational techniques. The geometries of CpM(NO)Cl2 (M = Cr, Mo), CpCr(NO)(NH2)X, and CpCr(NO)(CH3)X (X = Cl, CH3) were optimized at the DFT-B3LYP level for both the diamagnetic (S = 0) and paramagnetic (S = 1) electronic configurations. While the geometric parameters of the singlet compounds matched well with structures determined experimentally, the Cr−NO bond lengths in the triplet species exceeded the experimentally observed range by a significant margin, thereby indicating a propensity for nitrosyl-ligand dissociation from the high-spin complexes. The order of relative singlet vs triplet spin-state stability (expressed as ΔEs-t (kcal/mol)) was determined to be CpCr(NO)Cl2 (8.20) > CpCr(NO)(CH3)Cl (1.52) ≈ CpCr(NO)(NH2)Cl (0.95) > CpCr(NO)(CH3)2 (−2.37) > CpCr(NO)(NH2)CH3 (−9.55) > CpMo(NO)Cl2 (−17.62). The amide π-donation increases the HOMO−LUMO energy splitting, thus favoring the diamagnetic configuration. The alkyl ligand reduces the electron−electron repulsion through orbital expansion, thereby lowering the relative energy of the singlet state. Extended Hückel molecular-orbital calculations were performed on the DFT-optimized structures to help rationalize the metal−ligand bonding interactions, and interelectron repulsions were quantified by evaluation of the Coulomb (J) and exchange (K) integrals based on the B3LYP-optimized triplet spin-state geometries.

Published
1998
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22. Alignment dependent chemisorption of vibrationally excited CH4(ν3) on Ni(100), Ni(110), and Ni(111)

Author

Rainer D. Beck, Régis Bisson, Bruce L. Yoder, P. Morten Hundt, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Physique Moléculaire (LCPM), and Ecole Polytechnique Fédérale de Lausanne (EPFL)

Subjects
Angular momentum, General Physics and Astronomy, chemistry.chemical_element, Infrared spectroscopy, 010402 general chemistry, 01 natural sciences, 7. Clean energy, Dissociation (chemistry), quantum state–resolved, methane chemisorption, gas/surface reactivity, 0103 physical sciences, Physical and Theoretical Chemistry, Physics::Chemical Physics, 010304 chemical physics, surface reaction dynamics, [CHIM.CATA]Chemical Sciences/Catalysis, 0104 chemical sciences, reactant alignment effects, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Nickel, chemistry, Chemisorption, Excited state, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Atomic physics, Single crystal, Excitation
Abstract

We present a stereodynamics study of the dissociative chemisorption of vibrationally excited methane on the (100) (110) and (111) planes of a nickel single crystal surface. Using linearly polarized infrared excitation of the antisymmetric C–H stretch normal mode vibration (? 3 ) we aligned the angular momentum and C–H stretch amplitude of CH4 (? 3 ) in the laboratory frame and measured the alignment dependence of stateresolved reactivity of CH4 for the ?3 = 1 J = 0–3 quantum states over a range of incident translational energies. For all three surfaces studied in plane alignment of the C–H stretch results in the highest dissociation probability and alignment along the surface normal in the lowest reactivity. The largest alignment contrast between the maximum and minimum reactivity is observed for Ni(110) which has its surface atoms arranged in close packed rows separated by one layer deep troughs. For Ni(110) we also probed for alignment effects relative to the direction of the Ni rows. In plane C–H stretch alignment perpendicular to the surface rows results in higher reactivity than parallel to the surface rows. The alignment effects on Ni(110) and Ni(100) are independent of incident translational energy between 10 and 50 kJ/mol. Quantum state resolved reaction probabilities are reported for CH4 (? 3 ) on Ni(110) for translational energies between 10 and 50 kJ/mol. © 2011 American Institute of Physics.

Published
2011
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23. Cyclopentadienyl Chromium β-Diketiminate Complexes: Initiators, Ligand Steric Effects, and Deactivation Processes in the Controlled Radical Polymerization of Vinyl Acetate

Author

K. Cory MacLeod, Rinaldo Poli, Kevin M. Smith, Ulrich Baisch, Brian O. Patrick, Yohan Champouret, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Okanagan] (UBC Chemistry), University of British Columbia (UBC), Department of Chemistry [Vancouver] (UBC Chemistry), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Steric effects, Radical polymerization, chemistry.chemical_element, 010402 general chemistry, Ligands, 01 natural sciences, Polymerization, Inorganic Chemistry, chemistry.chemical_compound, Chromium, Cyclopentadienyl complex, Polymer chemistry, Organic compounds, Vinyl acetate, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, 010405 organic chemistry, Ligand, Organic Chemistry, Bond cleavage, 0104 chemical sciences, β diketiminate, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Vinyl
Abstract

International audience; The new compounds CpCr(nacnacAr,Ar′) with nacnacAr,Ar′ = Ar−N---C(Me)---CHC(Me)---N−Ar′ (Ar = Ar′ = C6H2Me3-2,4,6 or mes, 2; C6H3Et2-2,6 or dep, 3; Ar = C6H3Me2-2,6 or xyl and Ar′ = C6H3iPr2-2,6 or dipp, 4) have been synthesized and used in polymerization experiments in addition to the previously known analogues with Ar = Ar′ = xyl, 1, or dipp, 5. The compounds were used as moderators for the polymerization of vinyl acetate (VAc) initiated by V-70, according to an OMRP mechanism. The alkylchromium(III) thermal initiator CpCr(nacnacxyl,xyl)(CH2CMe3) (8) was synthesized from CpCr(nacnacxyl,xyl)(OTs) (7) and Mg(CH2CMe3)2(dioxane), while 7 was obtained from CpCr(nacnacxyl,xyl)Cl (6) and AgOTs. The polymerizations carried out with (1−5)/V-70/VAc at elevated temperatures yielded rapid deactivation, suggestive of irreversible radical trapping. On the other hand, room-temperature polymerizations carried out with 6/VAc proceeded, albeit slowly, to greater conversions. A labilizing effect of the Ar/Ar′ steric bulk is suggested by QM/MM calculations of CrIII−C BDE for models of the OMRP dormant species with 1, 5, and the parent system where Ar = Ar′ = Ph. Thermal deactivation of the nacnacxyl,xyl system has been evidenced, with formation of the acetate complex CpCr(nacnacxyl,xyl)(OAc), 9, as confirmed by an UV−vis study and by independent synthesis. This product is proposed to form by β-acetate transfer from the growing radical chain, triggered by a head−head monomer insertion. Compounds 2, 3, 6, 7, 8, and 9 have been structurally characterized by X-ray diffraction methods.

Published
2010
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24. Masitinib (AB1010), a potent and selective tyrosine kinase inhibitor targeting KIT

Author

Christian Auclair, Edwige Voisset, Laurent Gros, Anne Lermet, Olivier Hermine, Wolfgang Sippl, Patrice Dubreuil, Alain Moussy, Sébastien Letard, Berengere Hajem, Marco A. Ciufolini, Nathalie Casteran, Phillip S. Leventhal, Colin Mansfield, Laurence Borge, Michel Arock, Martine Humbert, Dubreuil, Patrice, AB Science SA, Centre de Recherche en Cancérologie de Marseille (CRCM / U891 Inserm), Institut Paoli-Calmettes, Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Martin-Luther-Universität Halle Wittenberg (MLU), Laboratoire de Biologie et de Pharmacologie Appliquée (LBPA), École normale supérieure - Cachan (ENS Cachan)-Centre National de la Recherche Scientifique (CNRS), Cytokines, hématopoïèse et réponse immune (CHRI), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), ANR RIB, ANR RIB, ANR MRAR, Ligue nationale contre le cancer, Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut Paoli-Calmettes, Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Fédération nationale des Centres de lutte contre le Cancer (FNCLCC), Centre de Recherche en Cancérologie de Marseille ( CRCM ), Aix Marseille Université ( AMU ) -Institut Paoli-Calmettes, Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Department of Chemistry, University of British Columbia ( UBC ), Institute of Pharmaceutical Chemistry, Martin-Luther-Universität, Laboratoire de Biologie et de Pharmacologie Appliquée ( LBPA ), École normale supérieure - Cachan ( ENS Cachan ) -Centre National de la Recherche Scientifique ( CNRS ), Cytokines, hématopoïèse et réponse immune ( CHRI ), Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), and ANR RIB,ANR RIB

Subjects
[SDV.MHEP.HEM] Life Sciences [q-bio]/Human health and pathology/Hematology, Models, Molecular, Pyridines, Drug Evaluation, Preclinical, Stem cell factor, Biochemistry, Tyrosine-kinase inhibitor, [ SDV.CAN ] Life Sciences [q-bio]/Cancer, chemistry.chemical_compound, Mice, 0302 clinical medicine, Piperidines, [ SDV.MHEP.HEM ] Life Sciences [q-bio]/Human health and pathology/Hematology, hématopoïèse, 0303 health sciences, Multidisciplinary, biology, Masitinib, [SDV.MHEP.HEM]Life Sciences [q-bio]/Human health and pathology/Hematology, [SDV.SP]Life Sciences [q-bio]/Pharmaceutical sciences, Protein-Tyrosine Kinases, Recombinant Proteins, 3. Good health, [SDV.SP] Life Sciences [q-bio]/Pharmaceutical sciences, Proto-Oncogene Proteins c-kit, 030220 oncology & carcinogenesis, Benzamides, Medicine, Female, Biochemistry/Drug Discovery, récepteur, Tyrosine kinase, Platelet-derived growth factor receptor, medicine.drug, Research Article, kinase, medicine.drug_class, Science, Mice, Nude, [SDV.CAN]Life Sciences [q-bio]/Cancer, Bone Marrow Cells, 03 medical and health sciences, Inhibitory Concentration 50, [SDV.CAN] Life Sciences [q-bio]/Cancer, LYN, signalisation, medicine, Animals, Humans, Protein Kinase Inhibitors, 030304 developmental biology, inhibiteur, Pharmacology, Tyrosine phosphorylation, Imatinib, [SDV.MHEP.DERM] Life Sciences [q-bio]/Human health and pathology/Dermatology, Thiazoles, [ SDV.SP ] Life Sciences [q-bio]/Pharmaceutical sciences, chemistry, Mutation, biology.protein, Cancer research, [ SDV.MHEP.DERM ] Life Sciences [q-bio]/Human health and pathology/Dermatology, [SDV.MHEP.DERM]Life Sciences [q-bio]/Human health and pathology/Dermatology, Pharmacology/Drug Development
Abstract

International audience; Background: The stem cell factor receptor, KIT, is a target for the treatment of cancer, mastocytosis, and inflammatory diseases. Here, we characterise the in vitro and in vivo profiles of masitinib (AB1010), a novel phenylaminothiazole-type tyrosine kinase inhibitor that targets KIT. Methodology/Principal Findings: In vitro, masitinib had greater activity and selectivity against KIT than imatinib, inhibiting recombinant human wild-type KIT with an half inhibitory concentration (IC50) of 200 ± 40 nM and blocking stem cell factor-induced proliferation and KIT tyrosine phosphorylation with an IC50 of 150 ± 80 nM in Ba/F3 cells expressing human or mouse wild-type KIT. Masitinib also potently inhibited recombinant PDGFR and the intracellular kinase Lyn, and to a lesser extent, fibroblast growth factor receptor 3. In contrast, masitinib demonstrated weak inhibition of ABL and c-Fms and was inactive against a variety of other tyrosine and serine/threonine kinases. This highly selective nature of masitinib suggests that it will exhibit a better safety profile than other tyrosine kinase inhibitors; indeed, masitinib-induced cardiotoxicity or genotoxicity has not been observed in animal studies. Molecular modelling and kinetic analysis suggest a different mode of binding than imatinib, and masitinib more strongly inhibited degranulation, cytokine production, and bone marrow mast cell migration than imatinib. Furthermore, masitinib potently inhibited human and murine KIT with activating mutations in the juxtamembrane domain. In vivo, masitinib blocked tumour growth in mice with subcutaneous grafts of Ba/F3 cells expressing a juxtamembrane KIT mutant. Conclusions: Masitinib is a potent and selective tyrosine kinase inhibitor targeting KIT that is active, orally bioavailable in vivo, and has low toxicity

Published
2009
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25. Directed evolution of new glycosynthases from Agrobacterium beta-glucosidase: a general screen to detect enzymes for oligosaccharide synthesis

Author

Melanie Mah, Laurent Gal, Christoph Mayer, Stephen G. Withers, R. A. J. Warren, Geoff Karjala, David L. Jakeman, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), and Department of Microbiology and Immunology [Vancouver] (UBC Microbiology)

Subjects
[SDV]Life Sciences [q-bio], Clinical Biochemistry, Oligosaccharides, Protein Engineering, 01 natural sciences, Chemical synthesis, Biochemistry, 03 medical and health sciences, chemistry.chemical_compound, Drug Discovery, Mass Screening, Glycosyl, Molecular Biology, Mass screening, 030304 developmental biology, chemistry.chemical_classification, Pharmacology, 0303 health sciences, 010405 organic chemistry, Chemistry, Beta-glucosidase, beta-Glucosidase, Glycosidic bond, General Medicine, Protein engineering, Glycosynthase, Directed evolution, Enzymatic oligosaccharide synthesis, 0104 chemical sciences, Mutation, Molecular Medicine, Glycosyl transfer, Directed Molecular Evolution, Plasmids, Rhizobium
Abstract

Background: Oligosaccharide synthesis is becoming increasingly important to industry as diverse therapeutic roles for these molecules are discovered. The chemical synthesis of oligosaccharides on an industrial scale is often prohibitively complex and costly. An alternative, that of enzymatic synthesis, is limited by the difficulty of obtaining an appropriate enzyme. A general screen for enzymes that catalyze the synthesis of the glycosidic bond would enable the identification and engineering of new or improved enzymes. Results: Glycosynthases are nucleophile mutants of retaining glycosidases that efficiently catalyze the synthesis of the glycosidic linkage by condensing an activated glycosyl fluoride donor with a suitable acceptor sugar. A novel agar plate-based coupled-enzyme screen was developed (using a two-plasmid system) and used to select an improved glycosynthase from a library of mutants. Conclusions: Plate-based coupled-enzyme screens of this type are extremely valuable for identification of functional synthetic enzymes and can be applied to the evolution of a range of glycosyl transferases.

Published
2001
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27. A Computational Study of Two-State Conformational Changes in 16-Electron [CpW(NO)(L)] Complexes (L=PH3, CO, CH2, HCCH, H2CCH2)

Author

Peter Legzdins, Rinaldo Poli, Kevin M. Smith, Laboratoire de Synthèse et Electrosynthèse Organométalliques (LSEO), Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB), Department of Chemistry [Vancouver] (UBC Chemistry), and University of British Columbia (UBC)

Subjects
Spin states, Chemistry, Ligand, Organic Chemistry, General Chemistry, State (functional analysis), Electron, Spin crossover, Catalysis, Tungsten, Ligand effects, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Crystallography, Density functional calculations, Hypersurface, Computational chemistry, Pi interactions, Pi interaction, Condensed Matter::Strongly Correlated Electrons, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Singlet state
Abstract

International audience; High-spin and low-spin [CpW(NO) (L)] complexes are calculated to be remarkably close in energy. Several critical conformational changes in the singlet compounds are predicted to proceed more readily by spin crossover to the triplet hypersurface. The relationships between spin state, π bonding, ligand orientation, and geometry at W are explored.

Published
1999
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28. Metal-based chirality and spin state change in 16-electron CpML2 systems: a computational study of CpW(NO)(PH3)

Author

Kevin M. Smith, Rinaldo Poli, Peter Legzdins, Laboratoire de Synthèse et Electrosynthèse Organométalliques (LSEO), Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB), Department of Chemistry [Vancouver] (UBC Chemistry), and University of British Columbia (UBC)

Subjects
Spin states, 010405 organic chemistry, Chemistry, Metals and Alloys, General Chemistry, Electron, 010402 general chemistry, 01 natural sciences, Molecular physics, Catalysis, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Metal, Planar, Computational chemistry, visual_art, Materials Chemistry, Ceramics and Composites, visual_art.visual_art_medium, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Density functional theory, Ground state
Abstract

International audience; Density functional theory calculations indicate that CpW(NO)(PH3) possesses a planar triplet ground state, a result with significant implications for the inversion of configuration of 16e, d6 CpML2 species.

Published
1998
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