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Cédric Caudan Ahlem Filali Dominique Lefebvre Mathieu Spérandio Elisabeth Girbal-Neuhauser 《Applied biochemistry and biotechnology》2012,166(7):1685-1702
A multi-method protocol previously proposed for the extraction of extracellular polymeric substances (EPS) from flocculated
sludges was investigated on dense aerobic granules. The protocol combines mechanical disruption by sonication and chemical
extraction using the Tween detergent and the cation chelator, EDTA. Polysaccharides were mainly recovered during the first
sonication step while proteins were recovered all along the extractive procedure with a high prevalence in the EDTA step.
These data confirmed the interest of the multi-method protocol for harvesting a diversified pool of EPS from dense granules
and for fractionation of the polymers according to their physicochemical properties. In addition, the high extractability
of proteins with EDTA confers a specific behavior of the aerobic granules towards the multi-method extraction protocol, supporting
the idea that proteins are associated in the granule matrix through ionic interactions involving divalent cations. Analysis
of the extracted EPS by anionic exchange chromatography confirmed the presence of highly anionic proteins that were specifically
detected in the extracts obtained from granules. One important question is now to investigate whether these highly anionic
proteins are involved in the aggregation and densification process and if their presence is related to the cohesive properties
of these particles. 相似文献
994.
Iminosugar‐Cyclopeptoid Conjugates Raise Multivalent Effect in Glycosidase Inhibition at Unprecedented High Levels 下载免费PDF全文
Dr. Mathieu L. Lepage Jérémy P. Schneider Dr. Anne Bodlenner Alessandra Meli Prof. Francesco De Riccardis Dr. Marjorie Schmitt Prof. Céline Tarnus Dr. Nha‐Thi Nguyen‐Huynh Dr. Yannis‐Nicolas Francois Dr. Emmanuelle Leize‐Wagner Dr. Catherine Birck Alexandra Cousido‐Siah Dr. Alberto Podjarny Prof. Irene Izzo Prof. Philippe Compain 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(15):5151-5155
A series of cyclopeptoid‐based iminosugar clusters has been evaluated to finely probe the ligand content‐dependent increase in α‐mannosidase inhibition. This study led to the largest binding enhancement ever reported for an enzyme inhibitor (up to 4700‐fold on a valency‐corrected basis), which represents a substantial advance over the multivalent glycosidase inhibitors previously reported. Electron microscopy imaging and analytical data support, for the best multivalent effects, the formation of a strong chelate complex in which two mannosidase molecules are cross‐linked by one inhibitor. 相似文献
995.
Cover Picture: An Experimental and Theoretical Investigation on Pentacoordinated Cobalt(III) Complexes with an Intermediate S=1 Spin State: How Halide Ligands Affect their Magnetic Anisotropy (Chem. Eur. J. 3/2016) 下载免费PDF全文
996.
Multicomponent Synthesis of Chiral Bidentate Unsymmetrical Unsaturated N‐Heterocyclic Carbenes: Copper‐Catalyzed Asymmetric CC Bond Formation 下载免费PDF全文
Dr. Claire Jahier‐Diallo Dr. Marie S. T. Morin Dr. Pierre Queval Dr. Mathieu Rouen Isabelle Artur Pierre Querard Dr. Loic Toupet Dr. Christophe Crévisy Dr. Olivier Baslé Dr. Marc Mauduit 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):993-997
A multicomponent strategy was applied to the synthesis of chiral bidentate unsaturated hydroxyalkyl‐ and carboxyalkyl‐N‐heterocyclic carbene (NHC) precursors. The newly developed low‐cost chiral ligands derived from amino alcohols and amino acids were evaluated in copper‐catalyzed asymmetric conjugated addition and asymmetric allylic alkylation, which afforded the desired tertiary and quaternary carbon stereocenters with excellent regio‐ and enantioselectivities (up to 99:1 e.r.). 相似文献
997.
In this paper we critically review detection limits of electrochemical DNA biosensors enabling DNA detection without target labelling. The review includes transduction principles and latest breakthroughs. To compare the efficiency of each type of electrochemical DNA biosensor, a simple DNA biosensors classification is established on the basis of the nature of the bio-electrochemical transduction. 相似文献
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Hélène D.S. Guerrand Ludovic D. Marciasini Thomas Gendrineau Oana Pascu Samuel Marre Sandra Pinet Michel Vaultier Cyril Aymonier Mathieu Pucheault 《Tetrahedron》2014
Palladium nanoparticles have been prepared using different techniques, CO2-assisted microfluidics coflow or thermolysis using ionic liquids. Both techniques displayed interesting activities in dehydrogenation of diisopropylamine–borane complex, and allowed performing a dehydrogenation–arylation sequence with the creation of a carbon–boron bond. 相似文献