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| Registros recuperados: 12 | |
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| Pigné, Sandrine; Zykwinska, Agata; Janod, Etienne; Cuenot, Stéphane; Kerkoud, Mohammed; Raulo, Roxane; Bataillé-simoneau, Nelly; Marchi, Muriel; Kwasiborski, Anthony; N’guyen, Guillaume; Mabilleau, Guillaume; Simoneau, Philippe; Guillemette, Thomas. |
| Background: Flavin-dependent monooxygenases are involved in key biological processes as they catalyze a wide variety of chemo-, regio- and enantioselective oxygenation reactions. Flavoprotein monooxygenases are frequently encountered in micro-organisms, most of which require further functional and biocatalytic assessment. Here we investigated the function of the AbMak1 gene, which encodes a group A flavin monooxygenase in the plant pathogenic fungus Alternaria brassicicola, by generating a deficient mutant and examining its phenotype. Results: Functional analysis indicates that the AbMak1 protein is involved in cell wall biogenesis and influences the melanization process. We documented a significant decrease in melanin content in the Äabmak1 strain... |
| Tipo: Text |
Palavras-chave: Monooxygenase; Cell wall; Melanin; Fungus; Flavoprotein. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00371/48189/48305.pdf |
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| Roux, Pauline; Siano, Raffaele; Collin, Karine; Bilien, Gwenael; Sinquin, Corinne; Marchand, Laetitia; Zykwinska, Agata; Delbarre-ladrat, Christine; Schapira, Mathilde. |
| High biomasses of the marine dinoflagellate Lepidodinium chlorophorum cause green seawater discolorations along Southern Brittany (NE Atlantic, France). The viscosity associated to these phenomena has been related to problems in oyster cultivation. The harmful effect of L. chlorophorum might originate from the secretion of Extracellular Polymeric Substances (EPS). To understand whether the EPS are produced by L. chlorophorum or its associated bacteria, or if they are a product of their interaction, batch cultures were performed under non-axenic and pseudo-axenic conditions for three strains. Maximum dinoflagellate cell abundances were observed in pseudo-axenic cultures. The non-sinking fraction of polymers (Soluble Extracellular Polymers, SEP), mainly... |
| Tipo: Text |
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| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00682/79403/81948.pdf |
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| Delbarre-ladrat, Christine; Salas, Marcia Leyva; Sinquin, Corinne; Zykwinska, Agata; Colliec-jouault, Sylvia. |
| Many bacteria biosynthesize structurally diverse exopolysaccharides (EPS) and excrete them into their surrounding environment. The EPS functional features have found many applications in industries such as cosmetics and pharmaceutics. In particular, some EPS produced by marine bacteria are composed of uronic acids, neutral sugars, and N-acetylhexosamines, and may also bear some functional sulfate groups. This suggests that they can share common structural features with glycosaminoglycans (GAG) like the two EPS (HE800 and GY785) originating from the deep sea. In an attempt to discover new EPS that may be promising candidates as GAG-mimetics, fifty-one marine bacterial strains originating from deep-sea hydrothermal vents were screened. The analysis of the... |
| Tipo: Text |
Palavras-chave: Exopolysaccharides; GAG; Marine bacteria; Glycopolymers; Sulfate; Production. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00399/51090/51873.pdf |
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| Akoumany, Katy; Zykwinska, Agata; Sinquin, Corinne; Marchand, Laetitia; Fanuel, Mathieu; Ropartz, David; Rogniaux, Hélène; Pipelier, Muriel; Delbarre Ladrat, Christine; Colliec Jouault, Sylvia. |
| Bacteria from deep-sea hydrothermal vents constitute an attractive source of bioactive molecules. In particular, exopolysaccharides (EPS) produced by these bacteria become a renewable source of both biocompatible and biodegradable molecules. The low molecular weight (LMW) derivatives of the GY785 EPS produced by the deep-sea hydrothermal vent strain Alteromonas infernus have previously displayed some biological properties, similar to those of glycosaminoglycans (GAG), explored in cancer and tissue engineering. These GAG-mimetic derivatives are obtained through a free radical depolymerization process, which could, however, affect their structural integrity. In a previous study, we have shown that A. infernus produces depolymerizing enzymes active on its own... |
| Tipo: Text |
Palavras-chave: Deep-sea bacterium; Alteromonas infernus; Wild-type strain; Exopolysaccharides; Glycosaminoglycan-mimetic; Enzymatic depolymerization; Structural analysis; Mass spectrometry. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00515/62644/67021.pdf |
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| Zykwinska, Agata; Berre, Ludivine Tripon-le; Sinquin, Corinne; Ropartz, David; Rogniaux, Helene; Colliec-jouault, Sylvia; Delbarre-ladrat, Christine. |
| Polysaccharides have attracted much attention due to their interesting physico-chemical and also biological properties that are explored in food, cosmetic and pharmaceutical industries. GY785 exopolysaccharide (EPS) presenting an unusual structure is secreted by the deep-sea hydrothermal bacterium, Alteromonas infernus. Low-molecular weight (LMW) derivatives obtained by chemical depolymerization of the native high molecular weight (HMW) EPS were previously shown to exhibit biological properties similar to glycosaminoglycans (GAG). In the present study, in order to generate well defined derivatives with a better control of the depolymerization, an enzymatic approach was applied for the first time. Various commercially available enzymes were firstly screened... |
| Tipo: Text |
Palavras-chave: Exopolysaccharide; Enzyme; Depolymerization; Oligosaccharide; Mass spectrometry. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00423/53458/54352.pdf |
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| Delbarre-ladrat, Christine; Sinquin, Corinne; Lebellenger, Lou; Zykwinska, Agata; Colliec-jouault, Sylvia. |
| Although polysaccharides are ubiquitous and the most abundant renewable bio-components, their studies, covered by the glycochemistry and glycobiology fields, remain a challenge due to their high molecular diversity and complexity. Polysaccharides are industrially used in food products; human therapeutics fall into a more recent research field and pharmaceutical industry is looking for more and more molecules with enhanced activities. Glycosaminoglycans (GAGs) found in animal tissues play a critical role in cellular physiological and pathological processes as they bind many cellular components. Therefore, they present a great potential for the design and preparation of therapeutic drugs. On the other hand, microorganisms producing exopolysaccharides (EPS)... |
| Tipo: Text |
Palavras-chave: Marine-derivedpolysaccharide; Biodiversity; Biologicalactivity; Structure; Modification; GAG-mimetic; Biosynthesis. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00241/35250/33764.pdf |
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| Norris, Karl; Mishukova, Oksana; Zykwinska, Agata; Colliec-jouault, Sylvia; Sinquin, Corinne; Koptioug, Andrei; Cuenot, Stéphane; Kerns, Jemma; Surmeneva, Maria; Surmenev, Roman; Douglas, Timothy. |
| Polysaccharides of marine origin are gaining interest as biomaterial components. Bacteria derived from deep-sea hydrothermal vents can produce sulfated exopolysaccharides (EPS), which can influence cell behavior. The use of such polysaccharides as components of organic, collagen fibril-based coatings on biomaterial surfaces remains unexplored. In this study, collagen fibril coatings enriched with HE800 and GY785 EPS derivatives were deposited on titanium alloy (Ti6Al4V) scaffolds produced by rapid prototyping and subjected to physicochemical and cell biological characterization. Coatings were formed by a self-assembly process whereby polysaccharides were added to acidic collagen molecule solution, followed by neutralization to induced self-assembly of... |
| Tipo: Text |
Palavras-chave: Marine exopolysaccharide; Collagen; Surface modification; Ti6Al4V. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00477/58881/61433.pdf |
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| Zykwinska, Agata; Marquis, Melanie; Godin, Mathilde; Marchand, Laetitia; Sinquin, Corinne; Garnier, Catherine; Jonchere, Camille; Chedeville, Claire; Le Visage, Catherine; Guicheux, Jerome; Colliec-jouault, Sylvia; Cuenot, Stephane. |
| Articular cartilage is an avascular, non-innervated connective tissue with limited ability to regenerate. Articular degenerative processes arising from trauma, inflammation or due to aging are thus irreversible and may induce the loss of the joint function. To repair cartilaginous defects, tissue engineering approaches are under intense development. Association of cells and signalling proteins, such as growth factors, with biocompatible hydrogel matrix may lead to the regeneration of the healthy tissue. One current strategy to enhance both growth factor bioactivity and bioavailability is based on the delivery of these signalling proteins in microcarriers. In this context, the aim of the present study was to develop microcarriers by encapsulating... |
| Tipo: Text |
Palavras-chave: Exopolysaccharide; Growth factor; Microparticles; Microfluidics; Bioactivity. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00477/58882/61432.pdf |
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| Marquis, Melanie; Alix, Valentin; Capron, Isabelle; Cuenot, Stephane; Zykwinska, Agata. |
| Alginate microgels are widely used as delivery systems in food, cosmetics, and pharmaceutical industries for encapsulation and sustained release of hydrophilic compounds and cells. However, the encapsulation of lipophilic molecules inside these microgels remains a great challenge because of the complex oil-core matrix required. The present study describes an original two-step approach allowing the easy encapsulation of several oil microdroplets within alginate microgels. In the first step, stable oil microdroplets were formed by preparing an oil-in-water (O/W) Pickering emulsion. To stabilize this emulsion, we used two solid particles, namely the cotton cellulose nanocrystals (CNC) and calcium carbonate (CaCO3). It was observed that the surface of the oil... |
| Tipo: Text |
Palavras-chave: Microparticles; Inonotropic gelation; Calcium carbonate particles; Cellulose nanocrystals; Microfluidics. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00333/44404/44272.pdf |
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| Grivaud-le Du, Alicia; Zykwinska, Agata; Sinquin, Corinne; Ratiskol, Jacqueline; Weiss, Pierre; Vinatier, Claire; Guicheux, Jerome; Delbarre-ladrat, Christine; Colliec-jouault, Sylvia. |
| Alteromonas infernus bacterium isolated from deep-sea hydrothermal vents can produce by fermentation a high molecular weight exopolysaccharide (EPS) called GY785. This EPS described as a new source of glycosaminoglycan-like molecule presents a great potential for pharmaceutical and biotechnological applications. However, this unusual EPS is secreted by a Gram-negative bacterium and can be therefore contaminated by endotoxins, in particular the lipopolysaccharides (LPS). Biochemical and chemical analyses of the LPS extracted from A. infernus membranes have shown the lack of the typical LPS architecture since 3-deoxy-d-manno-oct-2-ulopyranosonic acid (Kdo), glucosamine (GlcN), and phosphorylated monosaccharides were not present. Unlike for other... |
| Tipo: Text |
Palavras-chave: Marine Alteromonas infernus; Bacterial exopolysaccharide; Endotoxin; Characterization; Purification; Fermentation; Process. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00397/50818/51601.pdf |
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| Registros recuperados: 12 | |
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