NMR Analyses of the Enzymatic Degradation End-Products of Diabolican: The Secreted EPS of CNCM I-1629.

Diabolican, or HE800, is an exopolysaccharide secreted by the non-pathogenic Gram-negative marine bacterium (CNCM I-1629). This polysaccharide was enzymatically degraded by the WH2 hyaluronan lyase. The end products were purified by size-exclusion chromatography and their structures were analyzed in depth by nuclear magnetic resonance (NMR).

Structure of the Polysaccharide Secreted by CNCM I-5035 (Epidermist 4.0).

(CNCM I-5035) secretes an exopolysaccharide used as ingredient in cosmetic industry under the trademark Epidermist 4.0. It is appreciated for its ability to improve the physical and chemical barrier functions of the skin by notably increasing the keratinocyte differentiation and epidermal renewal.

Poloxamer 188-Coated Ammonium Methacrylate Copolymer Nanocarriers Enhance Loperamide Permeability across Pgp-Expressing Epithelia.

Loperamide is a μ-opioid agonist with poor gastrointestinal absorption, mainly because of its modest aqueous solubility and being a P-glycoprotein (Pgp) efflux substrate. Nevertheless, studies associated with therapeutic effects strongly suggest that loperamide holds potential pharmacological advantages over traditional μ-opioid agonists commonly used for analgesia. Thus, in this Communication, we assessed in MDCK-hMDR1 cell lines the effects over loperamide uptake and efflux ratio, when loaded into Eudragit RS (ERS) nanocarriers coated with poloxamer 188 (P188).

Viral degradation of marine bacterial exopolysaccharides.

The identification of the mechanisms by which marine dissolved organic matter (DOM) is produced and regenerated is critical to develop robust prediction of ocean carbon cycling. Polysaccharides represent one of the main constituents of marine DOM and their degradation is mainly attributed to polysaccharidases derived from bacteria. Here, we report that marine viruses can depolymerize the exopolysaccharides (EPS) excreted by their hosts using five bacteriophages that infect the notable EPS producer, Cobetia marina DSMZ 4741.

A mechanistic approach for the optimization of loperamide loaded nanocarriers characterization: Diafiltration and mathematical modeling advantages.

Oral bioavailability of loperamide is restricted by its limited absorption in the gastrointestinal tract due to its poor aqueous solubility and its P-glycoprotein (Pgp) substrate characteristic. In addition, ammonium methacrylate copolymers have shown to have mucoadhesive properties, whereas poloxamer 188, has been suggested as a Pgp inhibitor. Thus, in this work, we evaluate conditions that affect physicochemical parameters of ammonium methacrylate/poloxamer 188-based nanocarriers loaded with loperamide hydrochloride.

Structure of the Exopolysaccharide Secreted by a Marine Strain Vibrio alginolyticus.

(CNCM I-4151) secretes an exopolysaccharide whose carbohydrate backbone is decorated with amino acids, likely conferring its properties that are appreciated in cosmetics. Here, the secreted polysaccharide of another strain of (CNCM I-5034) was characterized by chromatography and one- and two-dimensional NMR spectroscopy experiments. The structure was resolved and shows that the carbohydrate backbone is made of four residues: D-galactose (Gal), D-galacturonic acid (GalA) D-N-acetylglucosamine (GlcNAc) and D-glucuronic acid (GlcA), forming a tetrasaccharide repetition unit [→4)-β-d-GlcA-(1→3)-α-d-Gal-(1→3)-α-d-GalA-(1→3)-β-GlcNAc(1→].

Depolymerization of Pseudomonas stutzeri exopolysaccharide upon fermentation as a promising production process of antibacterial compounds.

Many researchers have focused on high molecular weight (M) exopolysaccharides (EPS) as a source of potentially bioactive lower M derivatives. Therefore, it is of interest to find means for efficient and safe production of depolymerized-polymer derivatives. Exopolysaccharide-depolymerization products (EDP) varying in molecular weight were recovered from fermentative depolymerization of a native EPS produced by Pseudomonas stutzeri AS22.

Structure of an Amino Acid-Decorated Exopolysaccharide Secreted by a Vibrio alginolyticus Strain.

Vibrio alginolyticus (CNCM I-4994) secretes an exopolysaccharide that can be used as an ingredient in cosmetic applications. The structure was resolved using chromatography and one- and two-dimensional NMR spectroscopy experiments. The results show that the carbohydrate backbone is made of two residues: d-galacturonic acid and N-acetyl-d-glucosamine (GlcNac), which together constitute a tetrasaccharide repetition unit: [→3)-α-d-GalA-(1→4)-α-d-GalA-(1→3)-α-d-GalA-(1→3)-β-GlcNAc(1→].

Accumulation of nanoparticles in "jellyfish" mucus: a bio-inspired route to decontamination of nano-waste.

The economic and societal impacts of nano-materials are enormous. However, releasing such materials in the environment could be detrimental to human health and the ecological biosphere. Here we demonstrate that gold and quantum dots nanoparticles bio-accumulate into mucus materials coming from natural species such as jellyfish.

The marine bacteria Cobetia marina DSMZ 4741 synthesizes an unexpected K-antigen-like exopolysaccharide.

We have studied the exopolysaccharide produced by Cobetia marina DSMZ 4741, a marine bacterium isolated from coastal seawater. This strain is able to produce a polysaccharide in presence of carbon sources as glucose, mannitol and alginate. The maximum production occurs in aerobic condition, during the end of the exponential phase.

Characterization and structure of the polysaccharide produced by Pseudomonas fluorescens strain TF7 isolated from an arid region of Algeria.

Many bacteria possess a natural ability to synthesize and excrete exopolysaccharides which are widely varied in structure and function. These bacteria have the ability to solubilize inorganic phosphorus, which is important to promote growth and increase crop yields. The objective of this study is to select an adaptive strain to the constraints of erratic rainfall and large temperature variations and to determine the possible synergistic effects of its EPS and organic acid on tricalcium phosphate (TCP) solubilization.

Rhelogical, dermal wound healing and in vitro antioxidant properties of exopolysaccharide hydrogel from Pseudomonas stutzeri AS22.

The in vitro antioxidant activity and the in vivo wound healing performance of the exopolysaccharide EPS22, produced by Pseudomonas stutzeri AS22, were investigated. Antioxidant activity was evaluated by three different tests. The scavenging effect on DPPH radicals at a concentration of 1mg/ml was 80±1.

Characterization of the secretomes of two vibrios pathogenic to mollusks.

Vibrio tapetis causes the brown ring disease in the Japanese clam Ruditapes philippinarum while Vibrio aestuarianus is associated with massive oyster mortalities. As extracellular proteins are often associated with the virulence of pathogenic bacteria, we undertook a proteomic approach to characterize the secretomes of both vibrios. The extracellular proteins (ECPs) of both species were fractionated by SEC-FPLC and in vitro assays were performed to measure the effects of each fraction on hemocyte cellular parameters (phagocytosis and adhesion).

Optimization of exopolysaccharide production from Pseudomonas stutzeri AS22 and examination of its metal-binding abilities.

Aims: To investigate the effect of culture conditions and medium components on exopolysaccharide (EPS) production by Pseudomonas stutzeri AS22 and to access the EPS performance as a metal-binding exopolysaccharide.

Methods And Results: The EPS production conditions of Ps. stutzeri AS22 in submerged culture were optimized using two approaches for EPS quantification, and its metal-binding capacity was evaluated using both single and mixed metal ions systems.

Exopolysaccharide biosynthesis and biodegradation by a marine hydrothermal Alteromonas sp. strain.

Alteromonas macleodii subsp. fijiensis biovar deepsane is a deep-sea ecotype exopolysaccharide-producing bacteria isolated from the polychaete annelid Alvinella pompejana. The high molecular weight biopolymer HYD657 produced by this strain, is the first marine exopolysaccharide (EPS) to be commercialized for cosmetic use.

Purification and structural data of a highly substituted exopolysaccharide from Pseudomonas stutzeri AS22.

Pseudomonas stutzeri AS22, when grown on media containing starch and yeast extract and incubated at 30 °C and 200 rpm for 24h, was found to produce an acidic and high-molecular mass exopolysaccharide (EPS22). The EPS22 was purified and a yield of 1.3g/l was achieved.

Exopolysaccharides isolated from hydrothermal vent bacteria can modulate the complement system.

The complement system is involved in the defence against bacterial infection, or in the elimination of tumour cells. However, disturbances in this system contributes to the pathogenesis of various inflammatory diseases. The efficiency of therapeutic anti-tumour antibodies is enhanced when the complement system is stimulated.

Structural data on a bacterial exopolysaccharide produced by a deep-sea Alteromonas macleodii strain.

Some marine bacteria collected around deep-sea hydrothermal vents are able to produce, in laboratory conditions, complex and innovative exopolysaccharides. In a previous study, the mesophilic strain Alteromonas macleodii subsp. fijiensis biovar deepsane was collected on the East Pacific Rise at 2600 m depth.

Real-time PCR optimization to identify environmental Vibrio spp. strains.

Aims: To identify Vibrio vulnificus, Vibrio cholerae and Vibrio alginolyticus using standardized DNA extraction method and real-time PCR assays, among a large number of bacterial strains isolated from marine environment.

Methods And Results: Methods for DNA extraction and real-time PCR were standardized to identify a large number of Vibrio spp. strains isolated through regular collection campaigns of environmental samples.

Medium-throughput profiling method for screening polysaccharide-degrading enzymes in complex bacterial extracts.

Polysaccharides are the most abundant and the most diverse renewable materials found on earth. Due to the stereochemical variability of carbohydrates, polysaccharide-degrading enzymes - i.e.

Floridoside extracted from the red alga Mastocarpus stellatus is a potent activator of the classical complement pathway.

Many biological properties of algae have been found to have useful applications in human health, particularly in the fields of oncology and immunology. Floridoside, extracted from the red alga Mastocarpus stellatus, has a structure similar to the xenoantigen Gal alpha 1-3 Gal. This xenoantigen has been described to induce a high immune response in human xenografts and is mediated by natural anti-gal antibodies that activate the classical complement pathway.

Characterization of mannuronan C-5-epimerase genes from the brown alga Laminaria digitata.

Alginate is an industrially important polysaccharide obtained commercially by harvesting brown algae. The final step in alginate biosynthesis, the epimerization of beta-1,4-d-mannuronic acid to alpha-1,4-l-guluronic acid, a structural change that controls the physicochemical properties of the alginate, is catalyzed by the enzyme mannuronan C-5-epimerase. Six different cDNAs with homology to bacterial mannuronan C-5-epimerases were isolated from the brown alga Laminaria digitata (Phaeophyceae).

A novel, highly viscous polysaccharide excreted by an alteromonas isolated from a deep-sea hydrothermal vent shrimp.

A deep-sea, mesophilic, aerobic, and heterotrophic microorganism, able to produce an extracellular polysaccharide, was isolated from a shrimp collected near an active hydrothermal vent of the Mid-Atlantic Ridge. On the basis of phenotypic and phylogenetic analyses and DNA/DNA relatedness, this strain could be assigned to the species Alteromonas macleodii as a variant of the fijiensis subspecies. It was selected for its ability to exhibit a swarming mucoid phenotype on specific media.

Degradation of mannan I and II crystals by fungal endo-beta-1,4-mannanases and a beta-1,4-mannosidase studied with transmission electron microscopy.

We have used the endo-beta-1,4-mannanase from Trichoderma reesei (Tr Man5A), the endo-beta-1,4-mannanase from Aspergillus niger (An Man5A) and the exo-beta-1,4-mannosidase from A. niger (An Mnd2A) to follow the enzymatic degradation of mannan I and II crystals. The degradation process was studied by transmission electron microscopy and also followed by analysis of the released soluble reducing sugars.

Optimized mixtures of recombinant Humicola insolens cellulases for the biodegradation of crystalline cellulose.

The digestion of bacterial cellulose ribbons by ternary mixtures of enzymes consisting of recombinant cellulases (two cellobiohydrolases, Cel6A and Cel7A, and the endoglucanase Cel45A) from Humicola insolens was investigated over a wide range of mixture composition. The extent of digestion was followed by soluble sugar release (saccharification) analysis together with transmission electron microscopy (TEM) observations. It was found that the addition of minute quantities of Cel45A induced a spectacular increase in saccharification of the substrate with either Cel7A or the mixture of Cel6A and Cel7A.