Dissertations / Theses on the topic 'Fonctionnalisation des protéines'
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Briand, Elisabeth. "Fonctionnalisation de surfaces d'or et greffage de protéines pour l'élaboration d'un immunocapteur." Paris 6, 2007. http://www.theses.fr/2007PA066013.
Goux, Marine. "Fonctionnalisation de protéines alternatives aux anticorps appliquée à l'imagerie médicale en oncologie." Nantes, 2015. https://archive.bu.univ-nantes.fr/pollux/show/show?id=165df601-3118-437e-a459-a38b3257026e.
Positron-emission tomography (PET) is a medical imaging technique allowing diagnosis and therapy response monitoring in oncology. Biomarker targeting for PET imaging with antibodies, or their fragments, shows a lot of issues due to their slow blood clearance (size >100 kDa). Moreover, radiolabelling, which often occurs on lysines, is non-regioselective and leads to a heterogeneous mixture of products and sometimes protein inactivation. The development of new molecular probes for patient monitoring with small protein scaffolds as alternatives to antibodies, such as Nanofitins (NF), overcomes the limitations related to the size of the targeting agent (NF ≈ 10 kDa). We considered the use of a chemistry-free chelating system consisting of a highly phosphorylatable peptide tag to chelate radiometals, such as gallium-68. The approach is based on the natural ability of phosphate to interact strongly with metal ion. Genetically fused to a NF, the phosphorylatable peptide tag (phosphorylated in vivo or in vitro) allowed chelation of a lanthanide in solution, the Tb(III), with an affinity in the μM range. The second generation of peptide tag, artificially derived from a sequence of calcium-binding proteins, gave an affinity for Tb(III) around 500 nM and 50 nM at pH7 and pH5. 5 respectively ; and affinity for Ga(III) was obtained in the μM range at pH5. 5. Meanwhile, biodistribution studies and specific in vivo targeting of an anti-EGFR NF radiolabelled with 18FFBEM were evaluated in a double tumour-bearing mice model. PET images, obtained with a good tumour-tobackground contrast, provided the preclinical proof-of-concept that NF are efficient molecular imaging probes in oncology
Nesterenko, Alla. "Etude et fonctionnalisation de protéines végétales en vue de leur application en microencapsulation." Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0148/document.
Proteins extracted from vegetables are relatively low-cost, non-toxic, biocompatible and biodegradable raw materials. They represent a good alternative to animal-based proteins and petroleum-extracted polymers. In this study, proteins derived from soybean and sunflower seeds were used as wall materials for microencapsulation of hydrophobic (-tocopherol) or hydrophilic (ascorbic acid) active material by spray-drying technique. Soybean proteins are widely used in food and non-food applications, especially in microencapsulation. They were studied in this work as wall material of reference. Sunflower proteins are not actually used in industrial application, but only in the form of oil-cake for animal feeding. That’s why new ways of valorization of this agricultural by-product should be investigated. Several proteins’ modifications such as enzymatic hydrolysis, acylation, cross-linking and cationization were studied in order to improve encapsulating properties of wall material. In the context of green chemistry, all the modifications and preparations were performed without use of organic solvents and chemical catalysts. The effect of protein chemical and enzymatic modifications, and process parameters (homogenization pressure, wall/core ratio and protein concentration) on different characteristics of liquid preparations and microparticles (viscosity, emulsion droplet size, microparticle size and morphology) and on parameters related to the spray-drying process (yield and efficiency of microencapsulation) was particularly investigated in this study. The obtained results confirmed that sunflower proteins are quite suitable as encapsulating agent and provide the microencapsulation efficiencies significantly higher compared to those obtained with soy proteins
Garnier, Boris. "Développement de vecteurs liposomaux fonctionnalisés par des protéines dérivées de l’Annexine 5 et encapsulant des marqueurs pour l’imagerie." Thesis, Bordeaux 2, 2009. http://www.theses.fr/2009BOR21651/document.
This subject is in the framework of drug or imaging agent delivery system. This object must carry compound in an organism and selectively recognize a target area. The aims of my work were to add a targeting element to liposomes by use of Anx5 derivative and to encapsulate imaging compound inside the aqueous inner space. First we designed Anx5-bearing liposomes with the Anx5 protein covalently linked at the distal end of a PEG-lipid and used as targeting element. Anx5 conjugation was monitored by SDS-PAGE in order to control Anx5 density on the liposome surface. The influence of ligand density on the efficiency of binding to target membranes and on solutions dispersity was assessed by QCM-D and DLS. A density of 60 Anx5 / liposomes ensure the best target recognition efficiency and dispersity. Finally fluorescent dyes encapsulation was used to image the interaction between Anx5 bearing liposomes and apoptotic cells. To prepare magnetoliposomes we have synthesized and characterized the encapsulation of iron oxide nanoparticle inside neutral and anionic liposomes. The passive encapsulation procedure, the influence of the negative charge and the magnetoliposome stability were evaluated. The number of particle / vesicle was assayed and the liposomes aspect was examined using cryoelectron microscopy. An average of 50 particles / liposomes was encapsulated inside 100nm vesicles. Anionic lipids limit the encapsulation efficiency and promote liposomes destabilization. Finally the use of Anx5ZZ to anchor antibodies on the liposomes surface was characterized and optimized to use antibodies as homing device to target two diseases: atherosclerosis and inflammation. Lipid composition was optimized to stably entrap fluorescent dyes while Anx5 are bound on the membrane. To functionalize the vector, DLS and FRET experiment leads us to choose a sequence that consists in associating antibodies to the Anx5ZZ in a first time and then binding this complex on the liposome surface. Two antibodies were used to address the liposome toward biological targets, ex vivo on atherosclerosis models and in vivo on rats bearing inflammation areas
Schmidt, Grégory. "De la réalisation de transistors à effet de champ à nanotubes de carbone par fonctionnalisation chimique spécifique à la mesure optoélectronique d’un bio-hybride nanotubes/protéines photosynthétiques." Paris 11, 2009. http://www.theses.fr/2009PA112178.
The manuscript presents my work concerning the making and the study of a nanotube/photosynthetic protein bio-hybrids for optoelectronic applications. Indeed, photosynthetic proteins are super dyes with optoelectronic properties optimized by nature. So, we decided to check the possibility of protein integration in electronic device using carbon nanotubes as a nano-probe. During our work, the problem of making efficient carbon nanotubes field-effect transistors (CNTFETs) appeared. To solve this problem, we chose to enhance transistor performance using functionalisation by diazonium that is selective for metallic but not enough for sorting proposes. In the aim of increasing the selectivity, we decided to study the coupling mechanism which was unknown. Using kinetic studies, we showed that the reaction proceeds through a chain mechanism. In particular, the origin of the reaction selectivity was precisely determined and our work paves the way for selectivity improvement. Then, we improved the reaction selectivity using a Lewis base. Indeed, this addition increases dramatically the reaction selectivity for metallic nanotubes. Using this method, we realized efficient CNTFETs in high-volume. Promising results in the photosensitization of nanotubes by photosynthetic proteins were obtained. Indeed, we observed that the photo-induced dipolar moment created in proteins changed the electrical characteristics of CNTFET. The protein performance allowed increasing the optical sensitivity of the device. In particular, the protein activity proved robust in spite of protein fragility. Finally, this thesis opens the way to the protein integration in electronic or photovoltaic devices
Harari, Marine. "Mise au point de méthodes de synthèse pour la fonctionnalisation de composés hétérocycliques potentiels inhibiteurs de kinases." Rouen, 2016. http://www.theses.fr/2016ROUES021.
This thesis deals with the development of modulation strategies of the thiazoloquinazolinone structure. We are especially interested in elaborating transition metal-catalyzed methods in order to functionalize this heterocyclic system. Development of new synthetic routes for the synthesis of nitrogen containing analogues is also detailed. The first part of this manuscript concerns the use of transition metal in functionalization reactions in order to elaborate new tools for the modulation of thiazoloquinazolinones. Despite the failure with decyanative coupling reactions, the hydrodecyanation reactions took place in excellent yields. Direct C-H arylation reactions also were evaluated and efficient methods were elaborated with quinazolin-4(3H)-ones and thiazolo[5,4-f]quinazolin-9(8H)-ones substrates. The second part of this manuscript is focused on the synthesis of analogues containing an additional intracyclic nitrogen. Different pathways to access to these compounds are described. The third part deals with the biological evaluation of most of the compounds prepared along this work. Some protein kinases have been studied in order to evaluate the potential inhibition activity of our products
Joguet, Nicolas. "Utilisation et fonctionnalisation de protéines pour la conception de nouvelles microsphères permettant la protection et le relargage contrôlé de vitamine A." Thesis, La Rochelle, 2014. http://www.theses.fr/2014LAROS037.
The main objective of this thesis was to study the influence of functionalization of proteins by sugars or grape polyphenols in the vitamin A microsphere formulation and behavior. The formulation of different conjugated stemming either from the Maillard reaction or from the complexation of polyphenols on proteins was made on three proteins : pea proteins, sodium caseinate and type A gelatin. In a first part, the characteristics and the emulsifying power of the combined were studied, and confirmed the potential of stabilization of oil in the time. A second part was on the observations with scanning electron microscope of microspheres and on the methodology of specific observation in this kind of sample. The third part studied the influence of functionalization on vitamin A stability in the time, liberation on gastric or enteric digestion media, and liberation of co-encapsulated geraniol. The last study concerned the muco-adhesive potential of microspheres by using an original analysis
Issa, Sabin. "Fonctionnalisation de la surface du titane pour les implants dentaires." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1075/document.
The objective of this thesis is to create new nanostructured surfaces with bioactive coatings and to study theirs physicochemical properties in order to develop better dental implants designs and promote their osseointegration. This functionalization was performed in two steps; starting by the nanostructuration of TiO2 surface by anodisation to create reactive sites on the edges of titanium nanotubes which acts as points of “attachment" to bioactive coatings. The second step was the surface chemical modification by coating the nanostructured surface with bioactive coatings of calcium phosphate (CaP) and strontium doped calcium phosphate (Sr.CaP). This coating was performed by pulsed electrodeposition. The physicochemical characterization by XPS, SEM and IR showed that doping with Sr promotes a non-apatitic compound similar to DCPD or DCPA (Dicalcium Phosphate Dihydrate or Anhydrous), while undoped CaP coating looks like an amorphous apatite-like compound ACP. The addition of strontium has the double advantage of optimizing the cellular multiplication and of giving an inorganic phase with bio-performance better than apatitic compounds. We also evaluated the adsorption proprieties of these functionalized surfaces by investigating the adsorption of proteins (BSA). This adsorption was performed onto tblank nanotubes, nanotubes coated with CaP and Sr doped CaP and evaluated according to deposition time and to the pH value of the solution that affect both protein and surface charge. The kinetic and structural evaluation reveals different adsorption geometries according to pH and adsorption time and also according to the chemical nature of surface. Such results of protein adsorption and conformation may form a database to understand and control protein activities and reactions with living body when used for dental implants system
Sahnoun, Sophian. "C-H fonctionnalisation de purines : synthèse d’inhibiteurs potentiels de la HSP90." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA114803/document.
Resistance to current treatments of cancer encourages finding new therapeutical targets. The heat shock protein 90 (hsp90) is a molecular chaperon which regulates the folding of many client proteins associated with all of the six hallmarks of cancer, and helps maintaining their proper conformation. Consequently, the hsp90 has become an exciting new target in cancer drug discovery since the inhibition of its ATPase activity leads to depletion of these client proteins via the proteasomal pathway. PU3 and PU24S are purine-based hsp90 inhibitors functionalized on C-8 position. In the aim to identify more active compounds and/or new subfamilies of inhibitors, we have developed new metal-catalyzed C-H activation processes of various heterocycles including purines and other azoles. These new and simple approaches have allowed the access to numerous C-8 functionalized purines bearing (het)aryl, alkenyl and benzyl moieties
Baladi, Tom. "Autour du noyau imidazo[4,5-b]pyridine : inhibiteurs potentiels de la protéine kinase Tyro3 et fonctionnalisation directe de liaisons C – H." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS386/document.
Bladder cancer is a major medical issue, being the fourth most frequent cancer in men and treatable only with heavy surgery and/or broad-spectrum chemotherapy. This thesis project deals with the discovery of new targeted therapies of bladder cancer by blocking specifically, at a molecular scale in cancer cells, the signaling pathways in which protein kinase Tyro3 is involved. Indeed, its overexpression in most bladder cancers and the major part it plays in cancer cells survival have led to the validation of protein kinase Tyro3 as a therapeutic target for the treatment of bladder cancer. This thesis project can be divided into three main parts: the development of new synthetic methods around the imidazo[4,5-b]pyridine scaffold, the synthesis of a library of compounds using these methods and eventually the study of structure-activity relationships of these compounds versus Tyro3
Schmidt, Grégory. "De la réalisation de transistors à effet de champ à nanotubes de carbone par fonctionnalisation chimique spécifique à la mesure optoélectronique d'un bio-hybride nanotubes/protéines photosynthétiques." Phd thesis, Université Paris Sud - Paris XI, 2009. http://tel.archives-ouvertes.fr/tel-00448421.
Zemmour, Samira. "Nouvelle génération de colonnes capillaires ouvertes de dimension micronique pour l’analyse protéomique basées sur la fonctionnalisation de surface." Thesis, Lille 1, 2013. http://www.theses.fr/2013LIL10028.
The miniaturization of separative systems is continuously developing today. This emergence is due to the very low sample volume and the increasing need to save analysis time. The present thesis comprises two parts. The first one consists on developing a new generation of open capillary columns ("open tubular") based on micron-scale surface functionalization and characterization of their properties in proteomics analysis for the separation of peptide digests by reversed-phase liquid chromatography. The surface functionalization was carried out after activating silica capillary wall by grafting silylated derivatives including glycidyl methacrylate. The epoxide function was then broken by aliphatic primary amines to increase the hydrophobicity of the stationary phase. This two-step strategy has the advantage of allowing a split grafting of the functional unit and a wider variety of functionalizations. These columns were tested on standard peptides or peptide digests with analysis by MALDI-TOF offline and online nanoLC nanoESI-coupled ion trap. The effects of various parameters, particularly the length of the alkyl chain, on the retention of peptides were studied. The obtained results show that by decreasing the length of the amine carbon chain, peptides are eluted at a lower percentage of acetonitrile. In fact the shortening of the carbon chain results in the decrease of hydrophobic interactions and in faster peptides elution.The second part of this thesis presents preliminary developments of polymer grafting of type MIP (Molecular Imprinted Polymers) for the separation of peptides and proteins. The synthesis of molecularly imprinted phase is made from a mixture of monomers having acid or basic functions and imprint molecules that interact during the polymerization by non-covalent bonds. Once the polymerization is complete, the imprint molecules are removed from the polymer matrix, which results in the formation of a rigid polymer containing recognition sites that are specific to the model molecules. The molecularly imprinted columns were designed to selectively retain the target molecules or molecules similar in size and in structure, within a complex mixture by specific interactions. Affinity between two different peptides was obtained with good selectivity. Preparation of MIP and NIP (No Imprinted Polymers) columns was performed to compare the retention capacity of both materials and to verify the selectivity of the MIP uptake compared to NIP with respect to the target molecule. These columns were also tested by mass spectrometry MALDI-TOF
Anaya, Castro Maria Antonieta. "Optimisation de la pH-sensibilité de protéines végétales en vue d'améliorer leurs capacités d'encapsulation de principes actifs destinés à la voie orale." Thesis, Toulouse, INPT, 2018. http://www.theses.fr/2018INPT0017/document.
In the pharmaceutical field, the oral route remains the preferred route of administration because it is simpler and better accepted by patients. However, this mode of administration is problematic for many active pharmaceutical ingredients (API) with low solubility, low permeability and/or instability in the gastrointestinal environment. Their microencapsulation in polymeric matrices can make them able to respond to these factors, especially if the microparticles generated resist the environments encountered during the gastrointestinal tract and then play a protective role, both for the API and for the mucous membranes encountered. The search for new excipients, from agroresources such as natural polymers, is booming. Vegetable proteins, thanks to their functional properties such as good solubility, relatively low viscosity, and emulsifying and film-forming properties, are preferred candidates. In addition, the great diversity of their functional groups makes it possible to envisage various chemical or enzymatic modifications. The aim of this work was to study the interest of soy protein as a coating material for API intended for the oral route, and more particularly as a candidate for the development of gastro-resistant forms. A soy protein isolate (SPI) was used as a coating material and the atomization as a process. Ibuprofen, a nonsteroidal anti-inflammatory drug, was chosen as a model molecule because of its low solubility requiring an improvement in its bioavailability, and its gastric side effects requiring an enteric shaping. Two chemical modifications of proteins (acylation and succinylation) have been studied in order to modify the solubility of the soy protein. These modifications were carried out in accordance with the principles of Green Chemistry, especially in the absence of organic solvent. The microcapsules obtained by spray-drying were characterized in terms of rate and encapsulation efficiency, morphology and size distribution of the particles, physical state of the encapsulated API and capacity of release in simulated gastric and intestinal medium. The results obtained validated the interest of the chemical modifications of the soy protein to modulate the release kinetics of API. The chemical modifications appeared particularly suitable for the encapsulation of hydrophobic active ingredients, and allowed to obtain ibuprofen release kinetics decreased to acidic pH (gastric). The last part of this work allowed to validate this last hypothesis by the realization of gastro-resistant forms on the model of MUPS tablets (multiple unit pellet system). The results of this exploratory work demonstrate that soy protein, combined with a multiparticle shaping process coupled with direct compression, can be a biosourced, environmentally friendly alternative (aqueous solvent handling, drying and compression steps reduced) and confident to the coating used in traditional gastroresistant forms
Bernsmann, Falk. "Melanin made by dopamine oxidation : thin films and interactions with polyelectrolyte multilayers." Strasbourg, 2010. https://publication-theses.unistra.fr/public/theses_doctorat/2010/BERNSMANN_Falk_2010.pdf.
The spontaneous oxidation of dopamine in slightly alkaline solutions was investigated on the basis of the work of Lee and others [Science, 318:426-430, 2007], and the reaction product was identified as dopamine-melanin. The ability of melanin to covalently bind amine functional groups was confirmed by quantification of the corresponding binding sites on dopamine-melanin aggregates. Furthermore it is possible to redissolve dopamine-melanin aggregates in strongly alkaline solutions. The obtained small melanin grains were used to build layer-by-layer deposits with poly(diallyldimethylammonium). Different methods of dopamine oxidation to grow melanin films at solid--liquid interfaces were developed. All examined methods lead to continuous dopamine-melanin films with very similar surface morphologies. The dopamine-melanin films become impermeable to electrochemical probes at a thickness in the 10 nm range. In this context a higher permeability for positively charged and neutral probes than for negatively charged ones was confirmed for one preparation method. The adsorption of proteins on dopamine-melanin coatings was explained as combination of electrostatic and strong, most probably covalent, interactions. To obtain this explanation, the zeta-potential of dopamine-melanin deposits has been measured as a function of pH. The formation of melanin by dopamine oxidation in layer-by-layer films of poly(L-lysine) (PLL) and hyaluronate (HA) was studied: Melanin is able to homogeneously fill (PLL-HA)_n films and the obtained polyelectrolyte-melanin composites can be detached from their substrate as free-standing membranes prepared by a biomimetic method in mild conditions
Basse, Benoît. "Valorisation de la graine d'arachide broyée : rôle des différentes fractions dans la structuration par gélification d'une suspension aqueuse." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASB006.
The peanut (Arachis Hypogaea L.) is a legume widely consumed in southern countries (Africa, Asia and South-America). In these countries, it is an inexpensive, local food and a quality nutritional intake. However, alternative consumption patterns to raw peanut seed are rare. The company Onyx Développement has developed innovative food products based on gelled groundnut suspensions. The objective of this thesis is to study the structuring mechanisms of these suspensions (via different physical and enzymatic processes), and the structural properties of the gels formed. Peanut suspensions were prepared by grinding, in the presence of salt water, previously bleached seeds. We have shown that these suspensions can gel by processes usually used to form protein gels (acidification, heat treatment or enzymatic action). The suspensions were fractionated and each fraction was characterized in terms of composition and its role in the gelling process studied. The structural properties of the gels were evaluated by rheology and the microstructure of the network was observed by confocal microscopy. The extraction of proteins at different ionic strengths allowed us to preferentially solubilize certain globulins (arachin or conarachin) and their respective contribution to the gel structure was characterized. The effect of protein concentration, lipid fraction and particulate solid fraction were characterized in particular on gels obtained by heat treatment, with or without enzymatic pre-treatment with transglutaminase
Sharan, Siddharth. "Compréhension des mécanismes à l'origine des propriétés fonctionnelles et de la flaveur d’ingrédients riches en protéines issus de féveroles." Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASB061.
The growing population is demanding new healthy, sustainable solutions for foods and beverages. Fava bean (Vicia faba L.) is a promising plant source that can provide nutritional and functional ingredients for different food applications. Fava bean is processed to form ingredients and they can be further modified to render them fit for food applications. This PhD work aimed to understand the role of processing conditions on functional and flavor properties, and apply this understanding to produce and use fava bean protein-rich ingredients. It investigated the effects of certain industrially relevant process conditions using a cross-dimensional approach to find the right kind of compromise between different ingredients properties. To be precise, a very gently processed fava bean protein rich concentrate was industrially procured, which was then modified by process conditions such as pH (2, 4, 6.4 and 11), temperature (55, 75 and 95 °C) and treatment duration (30 and 360 min) to produce 36 different ingredients. These were further utilized at two pH (4 and 7) in systems close to beverage applications. During ingredient utilization, beverage functionalities (foam and emulsion) along with odor perception and non-volatile compounds were investigated for all ingredients as a function of process conditions.Results showed that process conditions were able to drive functional and flavor properties of the fava bean concentrate, strengthened by different statistical models. Foam and emulsion properties were predominantly governed by the pH during ingredient utilization. In general, utilization pH around the isoelectric point of fava proteins (pH 4) was not suitable for foam stability, emulsion capacity nor emulsion stability. Strong correlations between functional and physico-chemical properties were identified and explained by protein properties. In addition, flavor was heavily driven by the modification and utilization conditions, especially the pH.From gentler to vigorous process conditions, perception can be modified from more green to more cooked flavors, whereas different conditions of application (e.g. pH) can modulate between “sweet” and rancid perceptions. Considering volatiles composition, aldehyde signals were primarily detected in ingredient suspensions head-space. But furanoids, terpenoids, alcohols and ketones signals had the next higher contribution for modifications at pH2, 4, 6.4 and 11 respectively. Lipid oxidation was deemed important in generating volatiles, along with other reactions including proteins, sugars and carotenoids degradation. Going deeper into understanding of physico-chemical and sensory properties, determinants of antioxidant potential, taste (bitterness and astringency), color and even anti-nutritional effects were also investigated. Phenolic compounds (flavan-3-ols, flavones, flavonols, hydroxycinnamic acids) and saponins were significantly impacted by process conditions during ingredient modification, especially by pH. For phenolic compounds, acidic and alkaline conditions (pH 2, 4 and 11) were highly distinct compared to the non-pH adjusted process (pH 6.4) in changing the phenolic and saponin profiles of the ingredients. When looked closely at non-pH adjusted processes, their variability due to increasing degree of processing seemed to be either a function of their variable extractability and/ or their reactions involving their structural rearrangement.Thus, process conditions played an important role in fava bean ingredient properties, and this work opens up new arena for inter-disciplinary study based on nutritional (anti-oxidant and anti-nutritional aspects), sustainability (life cycle assessment), functionality (gelation) and sensory (texture, sweetness, bitterness) considerations of fava bean as potential ingredients for industrial food applications
Périé, Lucie. "Formulation et alvéolation de pâtes céréalières à l’aide d’ingrédients biosourcés." Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0090.
The replacement of controversial additives in cereal matrices represents a major challenge to meet consumers’ expectations. Leavening agents are functional ingredients that are required to obtain porous biscuit products according to industrial manufacturing methods. Their incorporation into biscuit dough determines the expansion of dough pieces during the baking stage. In this work, we considered two cereal doughs with different hydration levels that determine the gas incorporation pathways, aiming to completely suppress the need for leavening agents. In a low-hydration laminated biscuit dough, the study considered the use of baker's yeast as a substitute for leavening agents. The configuration of the gluten network conditions the dough elasticity and its ability to stretch to allow the biscuits to expand during baking. In a sponge drop (whipped) dough, air incorporation relies on the formation of a stable foam simultaneously with the gas release induced by the leavening agents. The removal of leavening agents from this matrix was enabled by using functionalized plant proteins through various treatments (physical or enzymatic). A design of experiments approach was implemented to optimize functionalities and thus, ensure the obtention of biscuits with a uniform crumb structure. During this process, the interfacial properties of the dough proteins determine their ability to stabilize the air bubbles in the matrix. These were studied using tensiometry and interfacial rheology
Maalouli, Nazek. "Développement d’un banc plasmonique en goutte et conception de nouvelles interfaces appliquées à la biodétection." Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10111/document.
Surface plasmon resonance (SPR) based biosensors have become very important tools for a sensitive, label-free and real-time detection of biochemical and biological interactions. Different aspects for plasmonic-based sensor have been investigated in this thesis such as the detection system configuration and the way molecules are linked to the SPR interfaces. In the first part of this thesis, the interest of a droplet-based SPR set-up was shown. This approach has allowed studying experimentally, for the first time, the excitation of surface plasmons by a diffraction grating chip, without integrated prisms. In the second part, different surface functionalization strategies have been developed on different thin film of a hybrid SPR interfaces. It was shown that silver-based SPR interfaces post-coated with amorphous silicon-carbon alloy (Ag/a-Si0.63C0.37) could be modified with amine-terminated nitrilotriacetic acid (NTA), a strong chelating agent for Cu2+ ions. The interaction with his-tagged peptides could be followed, in an easy manner, by the droplet-based SPR set-up. Motivated by the interest of the glycane-lectin interaction, glycan-modified SPR chips were developed. Alkynyl-terminated mannose/lactose were covalently linked to azide functionalized gold/silicon oxide (Au/SiOx) interfaces using a "click" chemistry approach, the sensing of two different lectins (Lens culinaris and Peanut Agglutinin) was validated. In parallel, "unmodified" glycans were covalently linked to azide-tetrafluorobenzoic acid by a photocoupling strategy. This strategy showed high efficiency in the specific recognition of lectins comparable to the one obtained in the case of "clicked" sugar
Li, Joaquim. "Nouvelles fonctionnalisations de polyoxométallates et étude de l'interaction polyoxométallate-protéine." Paris 6, 2009. http://www.theses.fr/2009PA066654.
Palestino, Escobedo Alma Gabriela. "Biosensing and light enhancement by means of biofunctionalized porous silicon devices." Montpellier 2, 2008. http://www.theses.fr/2008MON20046.
Bellat, Vanessa. "Ingénierie d'un nouveau nanobiohybride à base de nanorubans de titanates pour la médecine régénérative." Thesis, Dijon, 2012. http://www.theses.fr/2012DIJOS056/document.
This research work is devoted to new nanohybrid engineering composed of titanate nanoribbons for regenerative medicine. Over a first phase, nanoribbons were synthesized by hydrothermal treatment and their morphological, structural and chemical features were defined. A fine characterization by means of different techniques of transmission electron microscopy mainly enabled to determine their thickness; dimension which had never been measured so far. Subsequently, titanate nanoribbons were functionalized by different home-made heterobifunctional PEG. Those polymers present at one of their extremities specific functional groups being able to couple with numerous biological molecules. Some collagen type peptides containing cellular recognition sites were grafted onto those extremities. The so-formed nanobiohybrid will permit cellular adhesion and proliferation favouring in fine tissue healing and regeneration. To evaluate new nanohybrid biological properties, titanate nanoribbons cytoxicity and aggregating power were determined by MTT tests, performed on two cell populations (fibroblasts and cardiomyocytes) and platelet aggregation tests (human blood). Finally, when used to promote healing process, the new nanobiohybrid was formulated in the form of sodium alginate hydrogel permitting a direct application on damaged tissues. To confirm the interest of this galenic form, initial in vivo tests were realized
Dridi, Cyrine. "Production, traçage en temps réel de domaines de la fibronectine humaine recombinante et immobilisation des recombinants sur des surfaces bioactives : modèles ou à visées thérapeutiques." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCD092/document.
In this thesis, we have developed a novel method for producing and purifying the 9th and 10thdomains of type III human fibronectin in E.coli. This strategy combines three fusion partnersin tandem: a dual affinity tag (10xHis and SBP) and a coloring tag (the binding domain of cytochrome b5 heme) in the presence of a Tev cleaving site.This system has demonstrated its performance in the visual tracking of the expression,purification and quantification steps of CMAT-FNIII9-10. The presence of the dual affinity tag allows a simple purification step and offers a degree of purity up to 98%. Moreover, the cytochrome b5 showed its interest in the visual and quantitative monitoring of the CMATFNIII9-10 adsorption onto the surface of a plastic support. Then the biological activity of there combinant fragment was successfully validated. In this study, we constructed an adhesive matrix by combining the properties of PCL with those of CMAT-FNIII9-10. Immobilization of the recombinant fragments is carried out by an oriented adsorption of the fusion protein onto the PCL film through a streptavidin layer. This approach has led to the development of a bio-functionalized material by optimizing the exposure of cell attachment sites on the surface of the PCL by an oriented immobilization. The cellular response of human MSCs was effectively validated on this matrix, in the absence of serum and in the presence of BSA. The results of this experiment show that this strategy has helped to improve the exposure sites "RGD" and "PHSRN" promoting interaction with cellular receptors
Blin, Thomas. "Elaboration de revêtements macromoléculaires antibiofilms à base de peptides antibactériens." Rouen, 2011. http://www.theses.fr/2011ROUES023.
From a medical and economical point of view, biofilms have important negative impacts. Various approaches based on the immobilization of bactericidal substances have been developed to prevent biofilm formation on materials surfaces. However, they are not fully satisfying due to limited efficiency, toxicity, or emergence of multiresisting bacteria. Compared to these synthetic approaches, some living organisms have developed highly efficient strategies tested over eons to eliminate the microbial adhesion. For instance, amphibians excrete an epidermal mucus containing antibacterial peptides. Considering this last example, we synthesized various coatings based on hydrophilic and flexible macromolecules grafted by antibacterial peptides. First of all, copolymer brushes based on oligo(ethylene glycol) methacrylates were polymerized by ATRP from planar substrates and afterwards grafted by temporin‐1Va or magainin‐1 derivatives. This strategy was subsequently successfully adapted on microparticles and on thermoresponsive polymer rushes leading to thin films showing a modulation of their bactericidal properties with emperature. Moreover, polysaccharide layers were immobilized on gold surfaces, then rafted by magainin‐1. The microstructure of these layers was tuned to optimize the accessibility of the grafted peptide. The resulting coatings showed a high activity against various bacterial strains. This work paves the way to the development of new coatings fighting biofilms, notably for (bio)medical devices
Carriou, David. "Etude dynamique et structurale de biomolécules par microscopie à force atomique HS-AFM : application à une petite protéine de choc thermique sHsp." Phd thesis, Université de Bourgogne, 2012. http://tel.archives-ouvertes.fr/tel-00873331.
Collado, Ruiz Sandra. "Palladation et fonctionnalisation de pyrimidinones et d'imidazolones." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMIR21/document.
Since past decade, our laboratory is concerned with transition-metal catalyzed C-H functionalization of heterocycles. A recent research program is dedicated to the class of N-acyl amidine pro-aromatic heterocycles. This present thesis work is first directed to the pyrimidin-4-one series that remains highly sparsely evaluated. As main results, Pd(0)-catalyzed and Cu(I)-assisted C2-H arylation of pyrimidin-4-one flanked with picolinyl and other ortho-directed groups at the nitrogen atom was set up using arylhalides as coupling partners. The C5-substituted pyrimidin-4-ones were also evaluated. To pursue recent investigations in 4-alkyl and 4-arylidene imidazolone series leaing ding to innovative GFP probes, the second work aims at evaluating the first step of an ultimate intramolecular C-H/C-H coupling to stiffen the 4-arylidene imidazolone core. For that, the intramolecular ortho-palladation was achieved in collaboration with Dr. Esteban Urriolabeitia of the University of Zaragoza in Spain providing a broad panel of original imidazolone-based palladacycles. Their photophysical properties were determined and their reactivity towards cross-coupling as well as oxidating agents were also evaluated
Le, cigne Anthony. "Étude de l'influence du récepteur LRP-1 sur le potentiel invasif de cellules tumorales : mesures nanomécaniques et d'adhérence par microscopie à force atomique." Thesis, Reims, 2016. http://www.theses.fr/2016REIMS024/document.
The low-density lipoprotein receptor-related protein 1 (LRP-1) can internalize proteases involved in cancer progression and is thus considered a promising therapeutic target. However, it has been demonstrated that LRP-1 is also able to regulate membrane-anchored proteins. Thus, strategies that target LRP-1 to modulate proteolysis could also affect adhesion and cytoskeleton dynamics. Here, we investigated the effect of LRP-1 silencing on parameters reflecting cancer cells’ invasiveness by atomic force microscopy (AFM). The results show that LRP-1 silencing induces changes in the cells’ adhesion behavior, particularly the dynamics of cell attachment. Clear alterations in morphology, such as more pronounced stress fibers and increased spreading, leading to increased area and circularity, were also observed. The determination of the cells’ mechanical properties by AFM showed that these differences are correlated with an increase in Young’s modulus. Moreover, the measurements show an overall decrease in cell motility and modifications of directional persistence. An overall increase in the adhesion force between the LRP-1-silenced cells and a gelatin-coated bead was also observed. Ultimately, our AFM-based force spectroscopy data, recorded using an antibody directed against the β1 integrin subunit, provide evidence that LRP-1 silencing modifies integrin dynamics. Together, our results show that techniques traditionally used for the investigation of cancer cells can be coupled with AFM to gain access to complementary phenotypic parameters that can help discriminate between specific phenotypes associated with different degrees of invasiveness
Frippiat, Steven. "Synthèses et fonctionnalisations de noyaux imidazolones : utilisations innovantes d'isonitriles et d'oxazolines." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMIR17.
Up until now, arylidene-4-imidazolones and dialkyl-(4,4’)-imidazolones derivatives are subject of longing for scientists both in the field of materials with fluorescence properties, and medical area, in particular for the treatment of diseases such as cancer, high blood pressure or Alzheimer's disease. Chemists have constantly presented synthetic methods, each more original than the other for the synthesis of these imidazolones. However, these old methods can appear to be out of step with the demands for one-step access to a large panel of highly functional derivatives. In addition, these synthetic routes are no longer respond to current challenges : being more economical in terms of synthetic’s step but also of atoms. This is why it seemed important to us to come up with some solutions in order to respond to these problems according to a particular function: the isocyanide function
Peigneguy, Fanny. "Synthèses et Caractérisations de Glucides Électrostimulables pour des Applications Antifouling." Electronic Thesis or Diss., Angers, 2020. http://www.theses.fr/2020ANGE0073.
Marine biofouling represents the undesirable accumulation of biological organisms on the surfaces of structures submerged in seawater. Unfortunately, this natural phenomenon has serious economic, environmental and material consequences. Since the ban of some biocides in antifouling paints (TBT in January 2008) because of their toxicity on the nontargeted marine species and their accumulation in the marine environment, research has focused on the development of new efficient, durable and environmentally friendly antifouling coatings without releasing toxic species. Thus, the work of this thesis deal with the functionalization of glassy carbon surface by carbohydrates linked to an electrostimulable conjugated system via a triazole link in order to develop surfaces with antifouling activity. Indeed, this kind of coating was designed to intervene in the first steps of biofouling. First, the carbohydrate, which is very hydrophilic, should fight against the formation of the conditioning film by surronding itself with an aqueous barrier resistant to proteins. On the other hand, the continuous modification of charge state by applying an electric current to the electroactive conjugated system is expected to disrupt the bacterial colonization delaying the installation of marine biofilm. Our study is therefore based on the synthesis and the immobilization of electrostimulable carbohydrates on a glassy carbon surface by aromatic amine oxidation in organic and aqueous media. A microbiological test was carried out on one of the carbohydrate coatings in the presence of the TC8 bacterial strain in the wells of a microplate containing electrochemical cells connected to a potentiostat. Electrical stimulation of this coating allowed to improve its antibacterial properties
Abou, Hamad Nicole. "Conception de nouvelles pseudo-particules virales hybrides silice protéine à usage biomédicale et agroalimentaire." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2023. https://nuxeo.u-bourgogne.fr/nuxeo/site/esupversions/83c79834-6a33-47b4-b997-2050b6b640c8.
Human Norovirus (HuNoV) is the predominant etiological agent of viral gastroenteritis in all age groups, worldwide. Until recently, the study of human norovirus was hampered by the lack of a robust cell culture system. Biological studies of the capsid rely largely on the analysis of virus-like particles (VLPs) expressed by the baculovirus. Genotype GII.4 among HuNoVs has been the predominant variant for decades while GII.17 genotype was often detected in East Asia since 2014. Here, GII.17 and GII.4 baculovirus-expressed VLPs were used to study the biological (binding to HuNoV ligand, namely the ABO and Lewis antigens) and physicochemical properties (size, morphology, and charge) of the HuNoV capsid under different conditions (temperature, pH, and ionic strength). We demonstrated that GII.17 and GII.4 VLPs do not seem to follow a common mechanism of unfolding and disassembly. GII.17 showed a stability at lower and higher ionic strength while GII.4 aggregated at 10 mM ionic strength. The nature of the buffers influences the morphology and the stability of the VLPs. Here, both VLPs were highly stable from a pH 7 to 8.5 at 25°C. At acidic and basic pH, VLPs formed aggregates, which, in some cases, still recognized HBGAs. Increasing the temperature above 65°C altered the morphology of VLPs causing aggregation and decreased the affinity to HBGA. By comparing both isolates, GII.17 showed a better stability profile than GII.4 and was used in the second part of our work for the design of a silica-protein hybrid particle. GII.17 was activated by EDC and NHS and then mineralized by two silica precursors APTES and TEOS. Through physicochemical analysis, we produced a 44 nm hybrid particle which still recognizes HBGAs. The FITC was grafted onto the silica layer in order to obtain a fluorescent hybrid particle. The binding experiments of these VLPs carried out on healthy and cancerous tissues showed that these particles recognize inflammatory tissues. The multifunctional VLPs that we produced can then serve as a platform for the development of delivery systems (drug delivery) or “intelligent” vectors for therapeutic or agri-food purposes
Muselli, Mickaël. "Synthèse et fonctionnalisation directe catalytique de la liaison C-H d'imidazolones : nouvel accès aux fluorophores analogues de la GFP." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMIR10/document.
Imidazolones have been studied for a long time, either as bioactive molecules or for their fluorescence properties, the best known example being the Green Fluorescent Protein or GFP. Numerous syntheses are already described, in particular the condensation of an amine with an oxazolone (Erlenmeyer method). In this work, we not only improved the condensation protocol but also developed an original synthesis consisting in using 2-H imidazolones CH arylation. To this end, it was first necessary to develop a protocol for the synthesis of 2-H imidazolones, hitherto very little described, and then to develop the conditions for arylation and direct vinylation of these molecules. Two sets of imidazolones have been studied and published separately: first, the 4,4'- dialkylimidazolones, frequently used for their biological properties, followed by arylation and vinylation of 4-arylidene-2-H imidazolones
Roussille, Ludovic. "Suivi quantitatif in situ d'interactions biomoléculaire par microscopie optique SEEC." Thesis, Le Mans, 2012. http://www.theses.fr/2012LEMA1030/document.
This thesis was supported by National Agency for Research with the project: ANR PNANO-07 SEEC. The Surface Enhanced Ellipsometric Contrast (SEEC) microscopy has invented in 2000 at Le Mans (France). This technique allows the visualization of nanoscopic object between crossed analyzer and polarizer. It’s possible if some special multilayer surfaces are used. There surfaces must have the particularity to not change the polarization of light during the reflection. Until the beginning of the project the SEEC microscopy was useful only for air observations. The goal of the thesis was to adapt this technique to observe on gold surfaces immerged in water and to compare the performance of the SEEC microscopy with Surface Plasmonique Resonance (SPR) in that configuration. The SPR is a biomolecular interaction study reference technique. SEEC microscopy lateral resolution was evaluate by fluorescence microscopy. Next, we realize two model experiments monitor in parallel by SEEC microscopy and by SPR: BSA immobilization and biotinylated IgG fixation by immobilized streptavidine. To compare measurements efficiently we did a huge preparation work (surface functionalizations and microfluidic) to have exactly same conditions in both techniques.Our results show SEEC microscopy cannot replace SPR for biomolecular interaction studies but it can be used as cheap immunological diagnostic technique. This work gives the path to follow on that direction
El, Felss Nadia. "Céramiques phosphocalciques fonctionnalisées : étude des propriétés de surface par méthodes spectroscopiques." Thesis, Limoges, 2018. http://www.theses.fr/2018LIMO0109/document.
This work is ascribed within the framework of the development of osteoinductive biomaterials for the repair large bone defects. It is a contribution to the understanding of the physical and chemical interactions between phosphocalcic ceramics and two proteins of interest: fibronectin (Fn), a cell adhesion protein, and Vascular Endothelial Growth Factor (VEGF) which is involved in vascularisation and improvement of bone formation.Fibronectin/bioceramic physical interactions were studied by force spectroscopy to evaluate the influence of the topography and the chemical composition of phosphocalcic ceramics made of hydroxyapatite (HA), silicated hydroxyapatite (SiHA) and carbonated hydroxyapatite (CHA) on fibronectin adhesion. The results obtained in terms of force cartography do not indicate any impact of the polished ceramics chemistry on the surface distribution and intensity of adhesion forces. However, these forces are more intense at the level of the grain boundaries of unpolished ceramics, highlighting an influence of the topography modulated by the chemical composition.The protocol for functionalisation by VEGF consists of three steps: silanisation, addition of SM(PEG)6 and immobilisation of VEGF. VEGF/bioceramic chemical interactions were studied mainly by Raman imaging in order to follow the successive steps of the functionalisation by VEGF of the polished surface of ceramics made of hydroxyapatite (HA) and carbonated hydroxyapatite (CHA). This approach allowed to map the surface chemical changes and to point out the spatial distribution as well as the preferential reactions between the intermediate molecules and VEGF depending of the substrate
Abou-Dalle-Messaikeh, Hana. "Polymères insolubles fonctionnels : affinité spécifique pour les anticorps anti VIIIc." Paris 13, 1989. http://www.theses.fr/1989PA132006.
Sergeeva, Yulia. "Complexes ADN/polycation en solution et aux interfaces en tant que vecteurs de transfection non viraux de pointe." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01064224.