Consulta: creatorFacets:"Roger, Olivier"
Registros recuperados: 4
Data/hora: 16/06/2024 10:36:23

Structural studies of the main exopolysaccharide produced by the deep-sea bacterium Alteromonas infernus
Provedor de dados: 5
Autores: Roger, Olivier; Kervarec, Nelly; Ratiskol, Jacqueline; Colliec-jouault, Sylvia; Chevolot, Lionel.
The structure of the extracellular polysaccharide produced by the mesophilic species, Alteromonas infernus, found in deep-sea hydrothermal vents and grown under laboratory conditions, has been investigated using partial depolymerization, methylation analysis, mass spectrometry and NMR spectroscopy. The repeating units of this polysaccharide is a nonasaccharide with the following structure:   [GRAPHICS]   (C) 2004 Elsevier Ltd. All rights reserved.
Tipo: Text
Palavras-chave: Hydrothermal vent; Structure; Bacterial polysaccharide; Alteromonas.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-2112.pdf

Etude d'oligosaccharides bioactifs issus d'exopolysaccharides bactériens : obtention, caractérisation et relation structure/fonction
Provedor de dados: 5
Autores: Roger, Olivier.
Unusual exopolysaccharides (EPS) produced by heterotrophic aerobic and mesophilic bacteria originating from hydrothermal vent, were reviewed as a new source of polysaccharidic structures endowed with innovative biological properties. The first step of this study was the structure determination of the EPS GY785, synthesized by Alteromonas infernus. A highly branched nonasaccharidic repetitive unit was identified using chemical modifications and nuclear magnetic resonance spectroscopy. This 106 g/mol polysaccharide is composed of glucose, galactose, glucuronic acid, galacturonic acid, and contains a single branched ramification and one sulphate group.  The second step was the preparation of low molecular weight bioactive polysaccharides presenting interest...
Tipo: Text
Palavras-chave: Phosphorylation; Sulphation; Depolymerization; NMR spectroscopy; Structure; Deep sea hydrothermal vent; Bacteria; Exopolysaccharides; Activité anticoagulante; Phosphatation; Sulfatation; Dépolymérisation; Spectroscopie de RMN; Structure; Sources hydrothermales; Bactéries; Exopolysaccharides.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/these-622.pdf

Characterization, chemical modifications and in vitro anticoagulant properties of an exopolysaccharide produced by Alteromonas infernus
Provedor de dados: 5
Autores: Colliec-jouault, Sylvia; Chevolot, Lionel; Helley, Dominique; Ratiskol, Jacqueline; Bros, Andrée; Sinquin, Corinne; Roger, Olivier; Fischer, Anne-marie.
A new low-molecular-weight 'heparin-like' component was obtained from an exopolysaccharide produced by a mesophilic strain found in deep-sea hydrothermal vents. Data concerning the structure of the native high-molecular-weight exopolysaccharide (10(6) g/mol, 10% sulfate content) are reported for the first time. Two depolymerization processes were used to obtain low-molecular-weight (24-35 x 10(3) g/mol) oversulfated fractions (sulfate content 20 or 40%), Nuclear magnetic resonance studies indicated that after sulfation (40%), the low-molecular-weight fraction obtained by free radical depolymerization was less sulfated in the 6-O-position than the fraction depolymerized by acid hydrolysis. The free radical depolymerized product also had sulfated residues in...
Tipo: Text
Palavras-chave: Sulfation; Sulfated polysaccharide; Serpin; Heparin like; Depolymerization; Anticoagulant activity; Affinity co electrophoresis.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/publication-2111.pdf

Polysaccharide labelling: impact on structural and biological properties
Provedor de dados: 5
Autores: Roger, Olivier; Colliec-jouault, Sylvia; Ratiskol, Jacqueline; Sinquin, Corinne; Guezennec, Jean; Fischer, A; Chevolot, Lionel.
Three sulphated polysaccharides labelled at the reducing end with three different chemical treatments (2-aminopyridine (2-AP), 8-amino-1,3,6-trisulphonic acid (ANTS) and 6-(biotinyl)-aminocaproyl-hydrazide (BACH)) were compared. Molecular weight, chemical composition, nuclear magnetic resonance features and anticoagulant activity expressed as activated partial thromboplastin time were studied to determine whether structural and biological properties were retained or not after labelling. Partial depolymerisation and reduced biological activity were observed when reductive amination was performed with 2-AP. The initial properties were better retained with ANTS, and BACH did not modify the anticoagulant and structural properties. (C) 2002 Elsevier Science...
Tipo: Text
Palavras-chave: Anticoagulant activity; Reductive amination; Fluorescent tagging; Fucan; GAG; Sulphated polysaccharide.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/publication-2113.pdf