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deciphering the role of monosaccharides during phage infection of Staphylococcus aureus

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Nano Research 2022年第10期15卷 9234-9242页

作者： Baptiste Arbez Marion Gardette Christophe Gantzer Neus Vilà Isabelle Bertrand Sofiane El-Kirat-Chatel laboratoire de chimie physique et Microbiologie pour les Matériaux et l'environnement(lCPME) CNRSUniversité de Lorraine405 rue de Vandoeuvre54602 Villers-lès-NancyFrance

As phages are extensively investigated as novel therapy tools but also as transfer agents for antibiotic resistance genes,thorough understanding of phage–host interactions becomes *** for phage infection is its adhesion to the host ***,we used atomic force microscopy-based single-particle force spectroscopy with phage-decorated tips to decipher the adhesion of phage 187 on living Staphylococcus aureus *** found that addition of free N-acetyl-Dglucosamine was able to decrease phage adhesion,suggesting that this monosaccharide plays major role in phage 187 infection of ***,phage 187 adhesion on monosaccharide-coated model surfaces combined with plaque forming unit counts suggested that a direct link can be established between the propensity to bind to a saccharide and the capability of the latter to inhibit phage *** a nanoscale level,single-particle force spectroscopy was successfully used to identify a major receptor required for phage 187 infection of *** but also evidenced that this receptor was responsible for phage adhesion on *** work demonstrates that single-particle force spectroscopy is a powerful platform to screen and predict the molecular target of phages on their host surfaces.

关键词： atomic force microscopy single-particle force spectroscopy phage 187 Staphylococcus aureus phage-bacteria interactions

A quantum cascade laser infrared spectrometer for CO_2 stable isotope analysis：Field implementation at a hydrocarbon contaminated site under bio-remediation

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Journal of Environmental Sciences 2016年第2期28卷 60-74页

作者： Christophe Guimbaud Cécile Noel Michel Chartier Valéry Catoire Michaela Blessing Jean Christophe Gourry Claude Robert laboratoire de physique et de chimie de l'environnement et de l'Espace (lPC2E) CNRS et Universite d'Orleans (UMR 7328)45071 Orleans cedex 2 France Bureau de Recherches Geologiques et Minieres (BRGM) 45060 Orleans cedex 2 France

Real-time methods to monitor stable isotope ratios of CO_2 are needed to identify biogeochemical origins of CO_2 emissions from the soil–air interface. An isotope ratio infra-red spectrometer（IRIS） has been developed to measure CO_2 mixing ratio with δ~13C isotopic signature, in addition to mixing ratios of other greenhouse gases（CH_4, N2_O）. The original aspects of the instrument as well as its precision and accuracy for the determination of the isotopic signature δ~13C of CO_2 are discussed. A first application to biodegradation of hydrocarbons is presented, tested on a hydrocarbon contaminated site under aerobic bio-treatment. CO_2 flux measurements using closed chamber method is combined with the determination of the isotopic signature δ~13C of the CO_2 emission to propose a non-intrusive method to monitor in situ biodegradation of hydrocarbons. In the contaminated area, high CO_2 emissions have been measured with an isotopic signature δ~13C suggesting that CO_2 comes from petroleum hydrocarbon *** first field implementation shows that rapid and accurate measurement of isotopic signature of CO_2 emissions is particularly useful in assessing the contribution of contaminant degradation to the measured CO_2 efflux and is promising as a monitoring tool for aerobic bio-treatment.

关键词： Isotope ratio infrared spectrometry Isotopic signature δ^(13)C of CO_2 Biodegradation monitoring Hydrocarbons BTEX

Ab initio simulation of the sum-frequency generation response of optically active liquids in the presence of a dc electric field —determination of the absolute molecular configuration

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Science China Chemistry 2014年第10期57卷 1405-1408页

作者： CHAMPAGNE Benot QUINet Olivier laboratoire de chimie Théorique Unité de Chimie Physique Théorique et Structurale Université de Namur

Quantum chemical computations have been performed to evaluate the first and second hyperpolarizability quantities of the interference term, linear in the external static electric field, that appear in the electric field-induced sum-frequency generation signal of chiral liquids. These are performed at the time-dependent Hartree-Fock level on the prototypical 1,1′-bi-2-naphtol chiral species.

关键词： second and third hyperpolarizabilities chirality nonlinear optics time-dependent Hartree-Fock

SYNTHESIS OF SOlUBlE POlY(3,4-DIHYDROXY-o-TOlYlENE):REDOX POlYMER

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Chinese Journal of Polymer Science 2006年第1期24卷 41-46页

作者： Sad Moulay Fatima M'zyène laboratoire de chimie-physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de chimie Industrielle Université de BlidaRoute de SoumèaB.P.270Blida 09000Algeria. laboratoire de chimie-physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de chimie Industrielle Université de BlidaRoute de SoumaB.P.270Blida 09000Algeria.

Conventional chloromethylation, paraformaldehyde/hydrogen chloride in acetic acid medium, was applied to 1,2- dimethoxybenzene. Chloroform-soluble poly（3,4-dimethoxy-o-tolylene） was obtained with an intrinsic viscosity of 0.034 dl g^-1. The polymer was evaluated as a condensation redox polymer precursor formed by a Friedel-Crafts reaction. Cleavage of the methoxy groups present in this polymer resulted in poly（3,4-dihydroxy-o-tolylene） which manifested a great air-oxidation resistance. The redox property of the latter polymer was found to be 1017 mV by potentiometric titration with 0.05 N ceric ammonium nitrate at 25℃. This midpotential was compared to that of catechol, a monomeric analogue, under the same titration conditions.

关键词： Poly(3,4-dimethoxy-o-tolylene) Poly(3,4-dihydroxy-o-tolylene) Redox polymer.

HAlOMetHYlATION OF POlYSTYRENE AND SUBSEQUENT PYRIDINATION VIA A HOMOlYTIC PATHWAY

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Chinese Journal of Polymer Science 2006年第6期24卷 627-635页

作者： Sad Moulay Nadia Mehdi laboratoire de chimie-physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Departement de Chimie IndustrielleUniversité de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

Chloromethylation of polystyrene （PS） with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree of substitution of 89% was obtained. The Conant-Finkelstein reaction on the chloromethylated PS afforded soluble iodomethylated polystyrene with a degree of substitution as high as 96%. The reaction conditions of Minisci were employed to radically pyridinate PS via its iodomethylated derivative. Polyelectrolytes were formed which could be converted to normal polymers by treatment with a 20% aqueous solution of NaOH.

关键词： Chloromethylated polystyrene Conditions of Minisci Iodomethylated polystyrene Pyridinated polystyrene.

Synthesis, Structural Study and Phase Transitions Characterization by Thermal Analysis and Vibrational Spectroscopy of an Ammonium Rubidium Arsenate Tellurate

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Chemical Research in Chinese Universities 2016年第6期32卷 902-911页

作者： GHORBEl Khouloud lITAIEM Hajer KTARI lilia GARCIA-GRANDA Santiago DAMMAK Mohamed laboratoire de chimie Inorganique(lCI) Universitd de Sfax Facultd des Sciences de Sfax BP 1171 Sfax 3000 Tunisia laboratoire de chimie physique et Analytique Faeulte de Chimie Universitte d 'Oviedo Oviedo 33006 Espagne

The Rb2.42（NH4）0.58（HAsO4）（H2AsO4）. Te（OH）6 crystals（denoted by RbNAsTe） crystallize in the monoc-linic system, space group P21/n with the following parameters： a=1.3059（5） nm, b=0.6755（3） nm, c=1.6675（6） rim,β=94.126（4）°, Z=4 and V=1.46733（10） nm^3. Thermal analyses（DSC, DTA and TG） confirm the presence of the phasetransition and the temperatttre of the decomposition. The vibrational spectroscopy study at room temperature showthe presence and the independence of anionic groups, cationic groups, and give more importance to the hydrogenbonds. Raman spectra were recorded in the temperature range of 298--503 K. The temperature dependence of theRaman line shift, intensity reduction and the half width detects the phase transitions and confirms their nature. So, thephase transition at 453 K corresponds to the superprotonic-ionic conduction phase transition, and those at 483 and491 K correspond to the decomposition of our material.

关键词： RbNAsTe X-Ray diffraction Differential scanning calorimetry Phase transition Raman spectrometry

design of Watertight Barriers for Retention Ponds of Cyanide Using Sludge from Water Purification Station （Ziga）

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材料科学与工程（中英文B版） 2014年第6期4卷 186-193页

作者： David Y.K. Toguyeni Fabien Yonli laboratoire de physique et chimie de l 'environnement (lpce) UniversitO de Ouagadougou Burkina Faso

PYRIDINATION OF POlY(VINYl CHlORIde) via A HOMOlYTIC PATHWAY

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Chinese Journal of Polymer Science 2007年第3期25卷 297-302页

作者： Sad Moulay Zakia Zeffouni laboratoire de chimie-physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de Chimie IndustrielleUniversité Sad Dahlab de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

PVC was subjected to a chemical modification aiming at replacing the chlorine atoms by pyridine groups via a homolytic route. Pyridine groups were peculiarly affixed to the PVC matrix via a carbon-carbon bond rather than a carbonnitrogen one. PVC was first iodinated using the Conant-Finkelstein reaction, followed by the application of the homolytic conditions of Minisci to generate pyridinated PVC with a varying degree of substitution. The extent of substitution was not high; the reaction on 30% iodinated PVC afforded a degree of modification no greater than 3%.

关键词： Conditions of Minisci Iodinated PVC Pyridinated PVC

Investigation of structural parameters and self-aggregation of Algerian asphaltenes in organic solvents

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Petroleum Science 2015年第3期12卷 509-517页

作者： Asma larbi Mortada Daaou Abassia Faraoun laboratoire de Synthèse organique Physico-chimieBiomolcules et Environnement (LSPBE)Department of Industrial Organic ChemistryFaculty of ChemistryUniversity of Sciences and Technology of Oran laboratoire de chimie physique Macromoléculaire (lCPM) Department of ChemistryFaculty of SciencesUniversity of Oran

Elemental analysis, Fourier transform infrared （FTIR）, 1H-NMR, fluorescence spectroscopy, and surface tension methods have been used to characterize the molecular structure and the aggregation behaviors of two asphaltenic fractions derived, respectively, from an Alge- rian petroleum well and a corresponding storage tank deposit. Elemental analysis, FTIR, ~H-NMR, and fluores- cence spectroscopy were used to investigate the chemical composition and structural parameters of asphaltenes, while the surface tension method was used to measure the critical micelle concentration （CMC） in organic solvents with different solubility parameters and polarities in order to characterize the asphaltenes＇ aggregation behaviors. Results show that the unstable asphaltenes fraction extracted from the storage tank deposit possesses a higher polarity （higher heteroatoms content） and a lower aro- maticity than stable asphaltenes from the petroleum well. The CMC results indicate that asphaltenes with high polarity and low aromaticity have a high solubility in polar solvents such as nitrobenzene, whereas asphaltenes with low polarity and high aromaticity are more soluble in solvents with weak polarity, like toluene. It is concludedthat the difference of structure of asphaltene samples and polarity of solvents can lead to difference of aggregation behaviors.

关键词： Asphaltenes Algerian petroleum Structural parameters - CMC