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| Desriac, Florie; El Harras, Abderrafek; Simon, Matthieu; Bondon, Arnaud; Brillet, Benjamin; Le Chevalier, Patrick; Pugnière, Martine; Got, Patrice; Destoumieux-garzón, Delphine; Fleury, Yannick. |
| Discovery after discovery, host-associated microbiota reveal a growing list of positive effects on host homeostasis by contributing to host nutrition, improving hosts’ immune systems and protecting hosts against pathogens. In that context, a collection of oyster associated bacteria producing antibacterial compounds have been established to evaluate their role in non-host-derived immunity. Here, we described alterins; potent anti-Gram negative compounds produced by Pseudoalteromonas hCg-6 and hCg-42 isolated from different healthy oyster hemolymph. The strains hCg-6 and hCg-42 produce a set of at least seven antibacterial compounds, ranging from 926 to 982 Da structurally characterized as cyclolipopeptides (CLPs). Alterins share the same cationic... |
| Tipo: Text |
Palavras-chave: Pseudoalteromonas; Cyclolipopeptides; Alterin; Antibiotic. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00663/77511/79275.pdf |
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| Jouault, Albane; Gobet, Angelique; Simon, Marjolaine; Portier, Emilie; Perennou, Morgan; Corre, Erwan; Gaillard, Fanny; Vallenet, David; Michel, Gurvan; Fleury, Yannick; Bazire, Alexis; Dufour, Alain. |
| The aim was to identify and study the antibiofilm protein secreted by the marine bacterium Pseudoalteromonas sp. 3J6. The latter is active against marine and terrestrial bacteria, including Pseudomonas aeruginosa clinical strains forming different biofilm types. Several amino acid sequences were obtained from the partially purified antibiofilm protein, named alterocin. The Pseudoalteromonas sp. 3J6 genome was sequenced and a candidate alt gene was identified by comparing the genome-encoded proteins to the sequences from purified alterocin. Expressing the alt gene in another non-active Pseudoalteromonas sp. strain, 3J3, demonstrated that it is responsible for the antibiofilm activity. Alterocin is a 139-residue protein including a predicted 20-residue... |
| Tipo: Text |
Palavras-chave: Antibiofilm protein; Pseudoalteromonas; Pseudomonas aeruginosa; Biofilm. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00643/75517/76405.pdf |
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| Leroy, C.; Delbarre Ladrat, Christine; Ghillebaert, F.; Compere, Chantal; Combes, D.. |
| The antifouling potential of commercial hydrolases, four proteases, seven glycosidases and one lipase was evaluated on the adhesion of marine Pseudoalteromonas sp. D41. The experimental method, adapted to screen antifouling agents, was based on bacterial adhesion in natural sterile sea water in a microtiter plate and on total biomass quantification by the fluorescent dye DAPI (4[prime]6-diamidino-2-phenylindole). Savinase (subtilisin) was the most effective hydrolase in both the prevention of bacterial adhesion and the removal of adhered bacteria. However, some enzymatic preparations tested such as Amano protease were not only ineffective but also increased the number of adhered bacterial cells. Enumeration using epifluorescence microscopy of CTC... |
| Tipo: Text |
Palavras-chave: Marine biofilm; Antifouling; Pseudoalteromonas; Enzymes; Adhesion. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6140.pdf |
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| Gobet, Angelique; Barbeyron, Tristan; Matard-mann, Maria; Magdelenat, Ghislaine; Vallenet, David; Duchaud, Eric; Michel, Gurvan. |
| About half of seaweed biomass is composed of polysaccharides. Most of these complex polymers have a marked polyanionic character. For instance, the red algal cell wall is mainly composed of sulfated galactans, agars and carrageenans, while brown algae contain alginate and fucose-containing sulfated polysaccharides (FCSP) as cell wall polysaccharides. Some marine heterotrophic bacteria have developed abilities to grow on such macroalgal polysaccharides. This is the case of Pseudoalteromonas carrageenovora 9(T) (ATCC 43555(T)), a marine gammaproteobacterium isolated in 1955 and which was an early model organism for studying carrageenan catabolism. We present here the genomic analysis of P. carrageenovora. Its genome is composed of two chromosomes and of a... |
| Tipo: Text |
Palavras-chave: Carrageenan; CAZymes; Alginate; Gammaproteobacteria; Pseudoalteromonas; Marine bacteria; Algal holobiont; Biofilm. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00489/60070/63377.pdf |
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| López,Ruth; Monteón,Víctor; Chan,Ernesto; Montejo,Rubí; Chan,Manuel. |
| This study examined the effect of dissolved oxygen concentration on the production of biomass and metabolites with antimicrobial activity of Pseudoalteromonas sp cultured at 0, 150, 250, or 450 revolutions per minute (rev. min-1). Dissolved oxygen (D.O) was monitored during the fermentation process, biomass was quantified by dry weight, and antimicrobial activity was assessed using the disk diffusion method. The bacterium Pseudoalteromonas reached similar concentration of biomass under all experimental agitation conditions, whereas antimicrobial activity was detected at 0 and 150 rev. min-1 registering 0% and 12% of D.O respectively corresponding to microaerophilic conditions. Antibiotic activity was severely diminished when D.O was above 20% of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pseudoalteromonas; Oxygen limitation; Agitation rate; Microaerophilic. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822012000300048 |
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| Longeon, Arlette; Peduzzi, Jean; Barthelemy, Michel; Corre, Sophie; Nicolas, Jean-louis; Guyot, Museum National D'Histoire Naturelle. |
| A marine bacterium, X 153, was isolated from a pebble collected at St. Anne du Portzic (France). By 16S ribosomal DNA gene sequence analysis, X153 strain was identified as a Pseudoalteromonas sp. close to P. piscicida. The crude culture of X153 was highly active against human pathogenic strains involved in dermatologic diseases, and marine bacteria including various ichthyopathogenic Vibrio strains. The active substance occurred both in bacterial cells and in culture supernatant. An antimicrobial protein was purified to homogeneity by a 4-step procedure using size-exclusion and ion-exchange chromatography. The highly purified P-153 protein is anionic, and sodium dodecylsulfate polyacrylamide gel electrophoresis gives all apparent molecular mass of 87 kDa.... |
| Tipo: Text |
Palavras-chave: Probiotic bacteria; Pseudoalteromonas; Antimicrobial protein. |
| Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-426.pdf |
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| Pham, Dominique; Ansquer, Dominique; Chevalier, Anne; Dauga, Clement; Peyramale, Aude; Wabete, Nelly; Labreuche, Yannick. |
| In New Caledonia, shrimp hatcheries are confronted with mass mortality in the larval stages, a phenomenon poorly understood as no specific causative agent has been identified. This has resulted in an excessive use of prophylactic antibiotics, although their adverse effects in aquaculture are notorious. The present work was thus aimed at selecting potential probiotic strains for penaeid hatcheries. From a pool of more than 400 marine bacterial isolates sampled from the local marine environment seven strains exhibited in vitro antagonistic activity towards Vibrio harveyi. These isolates were characterized both phenotypically and genotypically using a biochemical approach and 16S rDNA sequencing. Six out of these seven strains were found to belong to the... |
| Tipo: Text |
Palavras-chave: Shrimp; Litopenaeus stylirostris; Probiotic; Hatchery; Pseudoalteromonas; Immune response. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00190/30129/28591.pdf |
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