Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
pseudoalteromonas antarctica sp. nov., isolated from an antarctic coastal environment.the taxonomic characteristics of five bacterial strains which were isolated from antarctic coastal marine environments were studied. these bacteria were psychrotrophic, aerobic, and gram negative with polar flagella. the g + c contents of the dnas of these strains were 41 to 42 mol%. the antarctic strains were phenotypically distinct from the previously described pseudoalteromonas type species. dna-dna hybridization experiments revealed that the new strains were closely related to each other but ...19979103620
use of a promoterless lacz gene insertion to investigate chitinase gene expression in the marine bacterium pseudoalteromonas sp. strain s9.sequence data for genes encoding 16s rrna indicated that the marine strain previously named pseudomonas sp. strain s9 would be better identified as a pseudoalteromonas sp. by use of transposon mutagenesis, a chitinase-negative mutant of s9 with a lacz reporter gene insertion was isolated. part of the interrupted gene was cloned and sequenced. the deduced amino acid sequence had homology to sequences of bacterial chitinases. expression of the chitinase gene promoter was quantified by measuring th ...19979251187
korormicin, a novel antibiotic specifically active against marine gram-negative bacteria, produced by a marine bacterium.a novel antibiotic named korormicin was isolated from the marine bacterium, pseudoalteromonas sp. f-420. this strain was isolated from the surface of a macro alga halimeda sp. collected from palau (the republic of belau). the planar structure of korormicin was determined by the result of 2d nmr studies and mass spectral data. korormicin had specific inhibitory activity against marine gram-negative bacteria, but was inactive against terrestrial microorganisms.19979592569
carbon dioxide as a regulator of gene expression in microorganisms.co2 regulates gene expression across a diverse group of microorganisms including fungi, and both photosynthetic and non photosynthetic bacteria. the processes that co2 regulates are diverse. several co2-responsive random promoter lacz fusions of unknown function have been isolated from a marine synechococcus and a pseudoalteromonas sp., highlighting the wide effect of co2 control in these organisms. regulatory proteins have been described that mediate the co2 response at transcription level in b ...19989602281
use of green fluorescent protein to tag and investigate gene expression in marine bacteria.two broad-host-range vectors previously constructed for use in soil bacteria (a. g. matthysse, s. stretton, c. dandie, n. c. mcclure, and a. e. goodman, fems microbiol. lett. 145:87-94, 1996) were assessed by epifluorescence microscopy for use in tagging three marine bacterial species. expression of gfp could be visualized in vibrio sp. strain s141 cells at uniform levels of intensity from either the lac or the npt-2 promoter, whereas expression of gfp could be visualized in psychrobacter sp. st ...19989647829
alpha-galactosidase of the marine bacterium pseudoalteromonas sp. kmm 701.an alpha-galactosidase that inactivates the group specificity of b erythrocytes (group iii) of human blood and does not affect a erythrocytes (group ii) was isolated from the marine bacterium pseudoalteromonas sp. kmm 701. the enzyme preparation did not contain lectin, hemolytic, sialidase, endoglycanase, or glycosidase activities. the enzyme is stable at 20 degreesc for 24 h, has ph optimum for catalysis within the range of 6.7-7.7, and is stable to high concentrations of nacl. it is 4-fold mor ...19989864457
[structure of glycerophosphate-containing o-specific polysaccharide from pseudoalteromonas sp. kmm 639].on the basis of acid hydrolysis, dephosphorylation, methylation, and 13c nmr spectroscopy data, the o-specific polysaccharide of pseudoalteromonas sp. kmm 639 was shown to be a glycerophosphate-containing polymer built of repeating disaccharide units of the following structure: [formula: see text]199810079941
multiple genes involved in chitin degradation from the marine bacterium pseudoalteromonas sp. strain s91.a cluster of three closely linked chitinase genes organized in the order chia, chib and chic, with the same transcriptional direction, and two unlinked genes, chip and chiq, involved in chitin degradation in pseudoalteromnas sp. strain s91 were cloned, sequenced and characterized. the deduced amino acid sequences revealed that chia, chib and chic exhibited similarities to chitinases belonging to family 18 of the glycosyl hydrolases while chip and chiq belonged to family 20. chip and chiq showed ...199910220172
determination of total protein content of bacterial cells by sypro staining and flow cytometry.an assay has been developed for measuring protein biomass of marine planktonic bacteria by flow cytometry. the method was calibrated by using five species of bacteria (an arcobacter sp., a cytophaga sp., an oceanospirillum sp., a pseudoalteromonas sp., and a vibrio sp.) recently isolated from seawater samples and grown in culture at different temperatures. the intensity of sypro-protein fluorescence of these bacteria strongly correlated with their total protein content, measured by the bicinchon ...199910388732
the complete genome sequence of pm2, the first lipid-containing bacterial virus to be isolated.bacteriophage pm2 was isolated from the pacific ocean off the coast of chile in the late 1960s. it was a new virus type, later classified as corticoviridae, and also the first bacterial virus for which it was demonstrated that lipids are part of the virion structure. here we report the determination and analysis of the 10, 079-bp circular dsdna genome sequence. noteworthy discoveries are the replication initiation system, which is related to the rolling circle mechanism described for phages such ...199910502514
inhibitor studies of a new antibiotic, korormicin, 2-n-heptyl-4-hydroxyquinoline n-oxide and ag+ toward the na+-translocating nadh-quinone reductase from the marine vibrio alginolyticus.a new antibiotic, korormicin, isolated from a marine bacterium pseudoalteromonas sp. f-420, was found to strongly inhibit the respiratory chain-linked na+-translocating nadh-quinone reductase (nqr) from the marine vibrio alginolyticus. similar to 2-n-heptyl-4-hydroxyquinoline n-oxide (hqno), korormicin specifically inhibited the na+-dependent reaction in the nqr complex that is directly coupled to the extrusion of na+ from the cells. both korormicin and hqno acted as purely noncompetitive inhibi ...199910549856
differentiation of chitinase-active and non-chitinase-active subpopulations of a marine bacterium during chitin degradation.the ability of marine bacteria to adhere to detrital particulate organic matter and rapidly switch on metabolic genes in an effort to reproduce is an important response for bacterial survival in the pelagic marine environment. the goal of this investigation was to evaluate the relationship between chitinolytic gene expression and extracellular chitinase activity in individual cells of the marine bacterium pseudoalteromonas sp. strain s91 attached to solid chitin. a green fluorescent protein repo ...200010919822
involvement of an extracellular protease in algicidal activity of the marine bacterium pseudoalteromonas sp. strain a28.the marine bacterium pseudoalteromonas sp. strain a28 was able to kill the diatom skeletonema costatum strain nies-324. the culture supernatant of strain a28 showed potent algicidal activity when it was applied to a paper disk placed on a lawn of s. costatum nies-324. the condensed supernatant, which was prepared by subjecting the a28 culture supernatant to ultrafiltration with a 10,000-m(w)-cutoff membrane, showed algicidal activity, suggesting that strain a28 produced extracellular substances ...200011010878
structure of an acidic o-specific polysaccharide of the marine bacterium pseudoalteromonas sp. kmm 634.an acidic o-specific polysaccharide containing d-glucuronic acid (d-glca), 2,3-diacetamido-2,3-dideoxy-d-glucuronic acid (d-glcnac3naca), 2,3-diacetamido-2,3-dideoxy-d-mannuronoyl-l-alanine (d-mannac3naca6ala), and 2-acetamido-2,4, 6-trideoxy-4-[(s)-3-hydroxybutyramido]-d-glucose (d-quinac4nacyl) was obtained by mild acid degradation of the lipopolysaccharide of the bacterium pseudoalteromonas sp. kmm 634 followed by gel-permeation chromatography. the polysaccharide was cleaved selectively with ...200011042499
genetic transformation system for a psychrotrophic deep-sea bacterium: isolation and characterization of a psychrotrophic plasmid.a versatile system that permits genetic manipulation of a psychrotrophic deep-sea bacterium, pseudoalteromonas sp. ps1m3, has been developed. a cryptic indigenous plasmid, pps1m3, of 3.1 kb from the above strain was isolated and characterized. the nucleotide sequence analysis of plasmid pps1m3 revealed the presence of one open reading frame, and its deduced amino acid sequence was identified as the essential protein for plasmid maintenance. transformation with the pps1m3 harboring antibiotic res ...200114961370
primary structure and chemical modification of some amino acid residues of bifunctional alginate lyase from a marine bacterium pseudoalteromonas sp. strain no. 272.the entire amino acid sequence of bifunctional alginate lyase from pseudoalteromonas sp. strain no. 272 were determined by two approaches, edman degradation of the peptides obtained from protease digestion of the enzyme protein and analysis of pcr products of the structural gene. the former resulted in incomplete amino acid sequence in the entire sequence, due to lacking of the proper peptides from the protease digestion. to compensate for this lack of sequences we applied the method of pcr of t ...200212523649
[antibiotic properties of the pseudoalteromonas genus bacteria isolated from the black sea water and molluscs].antagonistic properties of 41 strains of alteromonas-like bacteria isolated from the black sea water and molluscs have been studied. being grown on the rich medium "b" for marine bacteria, 21% of strains have shown high antagonistic activity against phytopathogenic fungi; 6% of strains inhibited the growth of bacillus subtilis, proteus vulgaris and candida albicans. spectrum of antagonistic activity was essentially changed on synthetic "bm" medium with acetate, glutamate, alpha-alanine as a sing ...200212190034
cloning and characterization of extracellular metal protease gene of the algicidal marine bacterium pseudoalteromonas sp. strain a28.the gene (empi) encoding an extracellular metal protease was isolated from a pseudoalteromonas sp. strain a28 dna library. the recombinant empi protein was expressed in e. coli and purified. paper-disk assays showed that the purified protease had potent algicidal activity. a skim milk-polyacrylamide gel electrophoresis protease assay showed that the 38-kda band of protease activity, which co-migrated with purified empi and was sensitive to 1,10-phenathroline, was detected in the extracellular su ...200212162559
two species of culturable bacteria associated with degradation of brown algae fucus evanescens.the heterotrophic microbial enrichment community established during degradation of brown algae fucus evanescens was characterized. a two-species bacterial community of marine culturable gamma-proteobacteria consisted of pseudoalteromonas and halomonas. the first member of the community, pseudoalteromonas sp., was highly metabolically active, had bacteriolytic and hemolytic activities, produced proteinases (gelatinase and caseinase), lipases, dnases, and fucoidanhydrolases, laminaranases, alginas ...200212023731
beta-galactosidase from a cold-adapted bacterium: purification, characterization and application for lactose hydrolysis.the enzyme beta-galactosidase was purified from a cold-adapted organism isolated from antarctica. the organism was identified as a psychotrophic pseudoalteromonas sp. the enzyme was purified with high yields by a rapid purification scheme involving extraction in an aqueous two-phase system followed by hydrophobic interaction chromatography and ultrafiltration. the beta-galactosidase was optimally active at ph 9 and at 26 degrees c when assayed with o-nitrophenyl-beta-d-galactopyranoside as subst ...200211935182
sensory, chemical and bacteriological changes during storage of iced squid (todaropsis eblanae).to relate sensory shelf-life of iced whole and gutted squid to bacterial growth and chemical changes.200211972700
enzymatically depolymerized alginate oligomers that cause cytotoxic cytokine production in human mononuclear cells.enzymatically depolymerized guluronate and mannuronate oligomers were prepared from polyuronates with an alginate lyase from a pseudoalteromonas sp., and their effects on mononuclear cells from human peripheral blood were examined. conditioned medium prepared by the incubation of cells with an untreated polyuronate had little effect on growth of human leukemic u937 cells, but a medium prepared with depolymerized uronate oligomers inhibited their growth. inhibition was greater in a medium prepare ...200312728983
antarctic marine bacterium pseudoalteromonas sp. 22b as a source of cold-adapted beta-galactosidase.the marine, psychrotolerant, rod-shaped and gram-negative bacterium 22b (the best of 41 beta-galactosidase producers out of 107 antarctic strains subjected to screening), classified as pseudoalteromonas sp. based on 16s rrna gene sequence, isolated from the alimentary tract of antarctic krill thyssanoessa macrura, synthesizes an intracellular cold-adapted beta-galactosidase, which efficiently hydrolyzes lactose at 0-20 degrees c, as indicated by its specific activity of 21-67 u mg(-1) of protein ...200312919815
root growth-promoting activity of unsaturated oligomeric uronates from alginate on carrot and rice plants.the root elongation activity of unsaturated oligomeric uronates from alginate on carrot and rice plants was investigated. unsaturated oligomeric uronates were prepared by digesting polymannuronate (pm) and polyguluronate (pg) with an alginate lyase purified from pseudoalteromonas sp. strain no. 272. the root elongation activity was measured by elongation in length of carrot- and rice-excised root incubated in the b5-medium containing 0.8% agar in the dark. pm and pg showed no activity, but the e ...200314519996
planar structure and antibacterial activity of korormicin derivatives isolated from pseudoalteromonas sp. f-420. 200314700281
pseudoalterobactin a and b, new siderophores excreted by marine bacterium pseudoalteromonas sp. kp20-4. 200314700282
a study of tryptophan fluorescence quenching of bifunctional alginate lyase from a marine bacterium pseudoalteromonas sp. strain no. 272 by acrylamide.a fluorescence quenching study of a sole tryptophan residue of a bifunctional alginate lyase from pseudoalteromonas sp. strain no. 272 was done in the presence and absence of substrates, oligomeric guluronic and its c5 isomer mannuronic acid, by a stern-volmer plot with a quencher, acrylamide. n-acetyltryptophanamide and reduced and carboxymethylated alginate lyase showed large quenching constants, on the other hand, the native enzyme had small constants regardless of the presence or absence of ...200314519987
screening and characterization of the protease cp1 produced by the moderately halophilic bacterium pseudoalteromonas sp. strain cp76.a total of 26 proteolytic moderate halophiles were isolated and characterized. most isolates were members of the genus salinivibrio (16 strains), while others were identified as bacillus (4 strains), salinicoccus (2 strains), or members of the gamma-proteobacteria (4 strains). strain cp76 was selected as the best producer of an extracellular protease, designated cp1, and was used for further studies. sequence analysis of the 16s rrna gene in addition to phenotypic tests led to the placement of t ...200312768453
a new precursor for the immobilization of enzymes inside sol-gel-derived hybrid silica nanocomposites containing polysaccharides.tetrakis(2-hydroxyethyl) orthosilicate (theos) introduced by hoffmann et al. (j. phys. chem. b., 106 (2002) 1528) was first used to prepare hybrid nanocomposites containing various polysaccharides and immobilize enzymes in these materials. two different types of o-glycoside hydrolyses (ec3.2.1), 1-->3-beta-d-glucanase liv from marine mollusk spisula sacchalinensis and alpha-d-galactosidase from marine bacterium pseudoalteromonas sp. kmm 701, were taken for the immobilization. to reveal whether t ...200414597186
[characterization and gene cloning of the endoglucanase from pseudoalteromonas sp. dy3 strain].a bacteria strain dy3 with high endoglucanse activity was isolated from deep sea sediment sample es0109. the 16s rdna sequence of dy3 exhibits identity of 99% with those of the same genus bacteria pseudoalteromonas citrea and pseudoalteromonas elyakovii . the celx gene of dy3 obtained by pcr method is 1479bp in length and encodes a protein of 492 amino acids. the protein encoded by celx gene exhibits 95% sequence identity with endoglucanase celg from pseudoalteromonas haloplanktis. there are two ...200415969114
purification and partial identification of novel antimicrobial protein from marine bacterium pseudoalteromonas species strain x153.a marine bacterium, x153, 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 ...200415747093
bacterial diversity in the bacterioneuston (sea surface microlayer): the bacterioneuston through the looking glass.the bacterioneuston is defined as the community of bacteria present within the neuston or sea surface microlayer. bacteria within this layer were sampled using a membrane filter technique and bacterial diversity was compared with that in the underlying pelagic coastal seawater using molecular ecological techniques. 16s rrna gene libraries of approximately 500 clones were constructed from both bacterioneuston and the pelagic water samples and representative clones from each library were sequenced ...200515819854
[cloning and expression of endoglucanase of marine cold-adapted bacteria pseudoalteromonas sp. mb-1].the cold-adapted gram-negative rod bacterium mb-1 which could secret cellulase was screened from mud of the bottom of the huanghai. according to the sequence of 16s rdna, this bacterium screened was identified as one species of pseudoalteromonas and was named as pseudoalteromonas sp. mb-1. the gene cela encoding cold-adapted endogluanase was cloned and then jointed to pgex-4t-1 to construct expression plasmid pgex-cela which was expressed in e. coli bl21. analysis to the supernatant of e. coli s ...200515847183
structure-activity relationship of alginate oligosaccharides in the induction of cytokine production from raw264.7 cells.guluronate and mannuronate oligomers with various degree of polymerization were prepared from polyguluronate (pg) and polymannuronate (pm) with an alginate lyase from a pseudoalteromonas sp., and their activities to induce cytokine secretion from mouse macrophage cell line raw264.7 cells were examined. enzymatically depolymerized unsaturated alginate oligomers induced tumor necrosis factor (tnf)-alpha secretion from raw264.7 cells in a structure-depending manner, while the activities of saturate ...200516055120
use of fluorophore-conjugated lectins to study cell-cell interactions in model marine biofilms.biofilms dominated by pennate diatoms are important in fields as diverse as ship biofouling and marine littoral sediment stabilization. the architecture of a biofilm depends on the fact that much of its mass consists of extracellular polymers. although most illuminated biofilms in nature are dominated by phototrophs, they also contain heterotrophic bacteria. given the close spatial association of the two types of organisms, cell-cell interaction is likely. fluorophore-conjugated lectins were use ...200515640218
cloning, expression, and purification of a recombinant cold-adapted beta-galactosidase from antarctic bacterium pseudoalteromonas sp. 22b.the gram-negative antarctic bacterium pseudoalteromonas sp. 22b, isolated from the alimentary tract of krill thyssanoessa macrura, synthesizes an intracellular cold-adapted beta-galactosidase. the gene encoding this beta-galactosidase has been pcr amplified, cloned, expressed in escherichia coli, purified, and characterized. the enzyme is active as a homotetrameric protein, and each monomer consists of 1028 amino acid residues. the enzyme was purified to homogeneity (50% recovery of activity) by ...200515596357
calcium influences cellular and extracellular product formation during biofilm-associated growth of a marine pseudoalteromonas sp.bacteria undergo a variety of physiological changes following a switch from planktonic growth to surface-associated biofilm growth. here, it is shown that biofilm development of a marine isolate, pseudoalteromonas sp. 1398, results in global changes in its cytosolic and extracellular proteomes. calcium influences these proteome responses, and affects the amount of surface-associated biomass and extracellular matrix material produced by pseudoalteromonas sp. 1398. four extracellular proteins, cha ...200516151201
crystallization and preliminary x-ray crystallographic studies of a psychrophilic subtilisin-like protease apa1 from antarctic pseudoalteromonas sp. strain as-11.the psychrophilic alkaline serine protease apa1 secreted by the antarctic psychrotroph pseudoalteromonas sp. strain as-11 consists of a subtilisin-like region (293 residues) and an additional insert region (148 residues) that does not show a sequence homology to any proteins in the rcsb protein data bank. apa1 inhibited with phenylmethanesulfonyl fluoride has been crystallized and x-ray diffraction data have been collected to 1.78 a resolution. the crystals belong to space group c2, with unit-ce ...200516511027
immunohistochemistry of great scallop pecten maximus larvae experimentally challenged with pathogenic bacteria.three challenge experiments were carried out on larvae of the great scallop pecten maximus. larvae were bath-challenged with vibrio pectenicida and 5 strains resembling vibrio splendidus and one pseudoalteromonas sp. unchallenged larvae were used as negative controls. the challenge protocol was based on the use of a multidish system, where the scallop larvae (10, 13 and 15 d post-hatching in the 3 experiments, respectively) were distributed to 2 ml wells with stagnant seawater and exposed to the ...200616724560
characterization and gene cloning of a cold-active cellulase from a deep-sea psychrotrophic bacterium pseudoalteromonas sp. dy3.the celx gene encoding an extracellular cold-active cellulase was isolated from a psychrotrophic bacterium, which was isolated from deep-sea sediment and identified as a pseudoalteromonas species. it encoded a protein consisting of 492 amino acids with a calculated molecular mass of 52.7 kda. the celx consisted of an n-terminal catalytic domain belonging to glycoside hydrolase family 5 and a c-terminal cellulose-binding domain belonging to carbohydrate-binding module family 5. the long linker se ...200616133657
a novel type of subtilase from the psychrotolerant bacterium pseudoalteromonas sp. sm9913: catalytic and structural properties of deseasin mcp-01.mcp-01, the main protease secreted by the deep-sea cold-adapted bacterium pseudoalteromonas sp. sm9913, is a cold-adapted serine protease. gene mcp01 encoding mcp-01 contains an orf of 2508 bp encoding a protein of 835 amino acid residues with an m(r) of 87 773 da, which is a multidomain subtilase precursor. mature mcp-01 purified from the culture of strain sm9913 with an m(r) of 65.84 kda is a multidomain protein composed of a catalytic domain, a linker, a p_proprotein domain and a polycystic k ...200717600056
structural characterization and ecological roles of a novel exopolysaccharide from the deep-sea psychrotolerant bacterium pseudoalteromonas sp. sm9913.pseudoalteromonas sp. sm9913 is a psychrotolerant bacterium isolated from deep-sea sediment. the structural characterization and ecological roles of the exopolysaccharide (eps) secreted by this strain were studied in this work. the yield of the eps increased as the culture temperature decreased in the range 30-10 degrees c, and it reached 5.25 g l(-1) (dry weight) under optimal growth conditions (15 degrees c, 52 h). eps fraction was purified and its structure was identified by the combination o ...200717464071
evidence for the involvement of pathogenic bacteria in summer mortalities of the pacific oyster crassostrea gigas.a study was conducted to investigate the involvement of bacteria in oyster mortalities during summer. moribund and apparently healthy oysters were sampled during mortality events along the french coast and in rearing facilities, usually when temperature reached 19 degrees c or higher, and oysters were in the gonadal maturation phase. hemolymph samples were aseptically withdrawn and submitted to bacteriological analysis. in healthy oysters, bacteria colonized hemolymph at low concentrations depen ...200717245611
molecular cloning and characterization of a novel beta-agarase, agab, from marine pseudoalteromonas sp. cy24.agarases are generally classified into glycoside hydrolase families 16, 50, and 86 and are found to degrade agarose to frequently generate neoagarobiose, neoagarotetraose, or neoagarohexaose as the main products. in this study we have cloned a novel endo-type beta-agarase gene, agab, from marine pseudoalteromonas sp. cy24. the novel agarase encoded by agab gene has no significant sequence similarity with any known proteins including all glycoside hydrolases. it degrades agarose to generate neoag ...200717166842
a marine bacterial adhesion microplate test using the dapi fluorescent dye: a new method to screen antifouling agents.to develop a method to screen antifouling agents against marine bacterial adhesion as a sensitive, rapid and quantitative microplate fluorescent test.200717397474
environmental stress determines the quality of bacterial lysate and its utilization efficiency in a simple microbial loop.heterotrophic bacteria provide the critical link in the microbial loop by converting dissolved organic matter (dom) into particulate form. in this study, dom was prepared from recently isolated estuarine bacterial strain vibrio sp. (dsm14379) grown at different salinities [0.2%, 0.5%, 3%, 5%, or 10% (w/v)], washed, concentrated, and lysed by autoclaving. the corresponding lysate-containing media were designated lm(0.2), lm(0.5), lm(3), lm(5), and lm(10). vibrio sp. cells grown at different salin ...200717406773
a cold-adapted esterase from psychrotrophic pseudoalteromas sp. strain 643a.a psychrotrophic bacterium producing a cold-adapted esterase upon growth at low temperatures was isolated from the alimentary tract of antarctic krill euphasia superba dana, and classified as pseudoalteromonas sp. strain 643a. a genomic dna library of strain 643a was introduced into escherichia coli top10f', and screening on tributyrin-containing agar plates led to the isolation of esterase gene. the esterase gene (esta, 621 bp) encoded a protein (esta) of 207 amino acid residues with molecular ...200717516048
immobilized preparation of cold-adapted and halotolerant antarctic beta-galactosidase as a highly stable catalyst in lactose hydrolysis.a cold-active beta-galactosidase of antarctic marine bacterium pseudoalteromonas sp. 22b was synthesized by an escherichia coli transformant harboring its gene and immobilized on glutaraldehyde-treated chitosan beads. unlike the soluble enzyme the immobilized preparation was not inhibited by glucose, its apparent optimum temperature for activity was 10 degrees c higher (50 vs. 40 degrees c, respectively), optimum ph range was wider (ph 6-9 and 6-8, respectively) and stability at 50 degrees c was ...200717059485
extracellular proteases from the antarctic marine pseudoalteromonas sp. p96-47 strain.the extracellular protease-production capacity of 33 bacterial isolates taken from marine biotopes in king george island, antarctica, was evaluated in liquid cultures. the p96-47 isolate was selected due to its high production capacity and was identified as pseudoalteromonas sp. the optimal growth temperature was 20 degrees c and the optimal for protease production was 15 degrees c. proteases were purified from culture supernatants, developing a multiple-band profile in zymograms. they were clas ...200818669056
molecular cloning, expression and characterization of alpha-amylase gene from a marine bacterium pseudoalteromonas sp. my-1.a gene (amya) encoding an extracellular alpha-amylase from a marine bacterium pseudoalteromnonas sp. my-1 was cloned and expressed in escherichia coli. it comprised an open-reading-frame of 2,007 base pairs and encoded a protein of 669 amino acids with a predicted molecular weight of 73,770 daltons and a pi of 5.15. the entire amino acid sequence of amya gene showed 86% similarity to the alpha-amylase preproprotein from pseudoalteromonas haloplanktis. it consisted of a signal peptide, alpha-amyl ...200819069841
hydrolysis of insoluble collagen by deseasin mcp-01 from deep-sea pseudoalteromonas sp. sm9913: collagenolytic characters, collagen-binding ability of c-terminal polycystic kidney disease domain, and implication for its novel role in deep-sea sedimentary particulate organic nitrogen degradation.collagens are the most abundant proteins in marine animals and their degradation is important for the recycling of marine nitrogen. however, it is rather unclear how marine collagens are degraded because few marine collagenolytic proteases are studied in detail. deseasins are a new type of multidomain subtilases. here, the collagenolytic activity of deseasin mcp-01, the type example of deseasins, was studied. mcp-01 had broad substrate specificity to various type collagens from terrestrial and m ...200818977758
accelerator analysis of tributyltin adsorbed onto the surface of a tributyltin resistant marine pseudoalteromonas sp. cell.tributyltin (tbt) released into seawater from ship hulls is a stable marine pollutant and obviously remains in marine environments. we isolated a tbt resistant marine pseudoalteromonas sp. tbt1 from sediment of a ship's ballast water. the isolate (10(9.3 +/- 0.2) colony-forming units ml(-1)) adsorbed tbt in proportion to the concentrations of tbtcl externally added up to 3 mm, where the number of tbt adsorbed by a single cell was estimated to be 10(8.2). the value was reduced to about one-fifth ...200819325731
effects of commercial enzymes on the adhesion of a marine biofilm-forming bacterium.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 ba ...200818058451
influence of subtilisin on the adhesion of a marine bacterium which produces mainly proteins as extracellular polymers.the nature of exopolymers involved in the adhesion of a marine biofilm-forming bacterium pseudoalteromonas sp. d41 was investigated to evaluate and understand the antifouling potential of subtilisin.200818489561
emulsifying and metal ion binding activity of a glycoprotein exopolymer produced by pseudoalteromonas sp. strain tg12.in this study, we describe the isolation and characterization of a new exopolymer that exhibits high emulsifying activities against a range of oil substrates and demonstrates a differential capacity to desorb various mono-, di-, and trivalent metal species from marine sediment under nonionic and seawater ionic-strength conditions. this polymer, pe12, was produced by a new isolate, pseudoalteromonas sp. strain tg12 (accession number ef685033), during growth in a modified zobell's 2216 medium amen ...200818552188
[antibacterial activity of sponge associated marine bacterium pseudoalteromonas sp. nj6-3-1 regulated by quorum sensing].we chose a sponge-associated marine-bacterium pseudoalteromonas piscicida nj6-3-1 to study whether its antibacterial activity were regulated by quorum sensing.200818590244
quorum sensing signaling molecules involved in the production of violacein by pseudoalteromonas.the production of violacein by pseudoalteromonas sp. 520p1 has many features of quorum sensing. signaling molecules were extracted from bacterial culture and subsequently identified as n-(3-oxooctanoyl)-homoserine lactone and n-tetradecanoyl-homoserine lactone. the former but not the latter induced the production of violacein in strain 520p1. we conclude that n-(3-oxooctanoyl)-homoserine lactone is a signaling molecule involved in the production of violacein.200818603795
adsorption of tributyltin by tributyltin resistant marine pseudoalteromonas sp. cells.the isolate, pesudoalteromonas sp. tbt1, could grow to overcome the toxicity of tributyltin chloride (tbtcl) up to 30 microm in the absence of cl(-) in the medium until the cells reached an exponential phase of growth. the viability, however, was reduced after the cells reached a stationary phase. the degradation products, such as dibutyltin (dbt) and monobutyltin (mbt), were not detected in the growth medium, indicating that the isolate has no ability to degrade tbt into less toxic dbt and mbt. ...200818468645
extracellular proteases and possible disease related virulence mechanisms of two marine bacteria implicated in an opportunistic bacterial infection of nephrops norvegicus.the extracellular products (ecp) secreted by two strains of gram-negative bacteria isolated from nephrops norvegicus exhibiting signs of an opportunistic bacterial infection were investigated with the objective of understanding their role in the spoilage of host muscle tissue and identifying disease related virulence mechanisms. ecp from vibrio sp. demonstrated no proteolytic activity. ecp from pseudoalteromonas sp. (isolate n10) degraded several substrates, including azocasein and host muscle t ...200818617185
dose-dependent significance of monosaccharides on intracellular alpha-l-rhamnosidase activity from pseudoalteromonas sp.intracellular alpha-l-rhamnosidase (ec 3.2.1.40) from the psychrotolerant pseudoalteromonas sp. 005nj showed a dose-dependent inhibition for l-rhamnose (ic(50) = 20 mm) and d-ribose (ic(50) = 95 mm), whereas d-glucose and l-fucose presented a lower inhibition, with ic(50) values as high as >0.5 and >0.2 m, respectively. on the other hand, d-fructose enhanced enzyme activity threefold, reaching a plateau of maximum specific activity between 0.2 and 0.4 m of this monosaccharide. both effects, low ...200818663413
flocculation behavior and mechanism of an exopolysaccharide from the deep-sea psychrophilic bacterium pseudoalteromonas sp. sm9913.flocculation behavior and mechanism of the exopolysaccharide secreted by pseudoalteromonas sp. sm9913 (eps sm9913), a psychrophilic bacterium isolated from 1855m deep-sea sediment, has been studied in this paper. eps sm9913 showed a peak flocculating activity of 49.3 in 1g/l kaolin suspension with 4.55mmol/l cacl2 and the optimum ph range of 5-8. it appears that the flocculating activity of eps sm9913 was stimulated by ca2+ and fe2+. this study found that eps sm9913 showed a better flocculation ...200818353634
extracellular secretion of pseudoalteromonas sp. cold-adapted esterase in escherichia coli in the presence of pseudoalteromonas sp. components of abc transport system.recently we described identification and characterization of gdsl esterase esta from psychrotrophic bacterium pseudoalteromonas sp. 643a. attempts to obtain heterologous overexpression of this enzyme in escherichia coli system were not satisfactory. the esta protein was expressed as inclusion bodies, most of that were inactive after purification step, and the recovery of esterolytic activity was very low after refolding. based on the sequence analysis we found that the esterase esta gene is clus ...200818700165
optimization of kappa-carrageenase production by pseudoalteromonas sp. aj5.to optimize the culture conditions of pseudoalteromonas sp. aj5 for a higher production of extracellular kappa-carrageenase.200818720840
purine nucleoside phosphorylase from pseudoalteromonas sp. bsi590: molecular cloning, gene expression and characterization of the recombinant protein.the gene encoding purine nucleoside phosphorylase (pnp) from the cold-adapted marine bacterium pseudoalteromonas sp. bsi590 was identified, cloned and expressed in escherichia coli. the gene encodes a polypeptide of 233 amino acids with a calculated molecular weight of 25,018 da. pseudoalteromonas sp. bsi590 pnp (pipnp) shares 60% amino sequence identity and conservation of amino acid residues involved in catalysis with mesophilic escherichia coli deod-encoded purine nucleoside phosphorylase (ec ...200818299797
molecular characterization of a cryptic plasmid from the psychrotrophic antarctic bacterium pseudoalteromonas sp. 643a.we report the identification and nucleotide sequence analysis of pkw1, a plasmid of the psychrotrophic bacterium pseudoalteromonas sp. 643a isolated from the stomach of antarctic krill euphasia superba. pkw1 consists of 4583 bp, has a g+c content of 43% and seven putative open reading frames (orfs). the deduced amino acid sequence from orf-1 shared significant similarity with the plasmid replicase protein of psychrobacter cryohalolentis, strain k5. the dna region immediately downstream of the or ...200818611409
purification and biochemical characteristic of a cold-active recombinant esterase from pseudoalteromonas sp. 643a under denaturing conditions.in this paper production of a cold-active esterase esta from the antarctic bacterium pseudoalteromonas sp. 643a in e. coli expression system was described. the purification and biochemical characteristic of esta were performed in the presence of urea and then compared with results obtained for the esterase with no addition of urea and isolated from the native source. in both cases the cold-active enzyme displayed similar properties. however, the differences concerning thermal activity were obser ...200919899613
cellulase production from pseudoalteromonas sp. no3 isolated from the sea squirt halocynthia rorentzi.pseudoalteromonas sp. no3 was isolated from the hemolymph of diseased sea squirts (halocynthia rorentzi) with symptoms of soft tunic syndrome. the strain was found to produce an extracellular cellulase (cely) that consisted of a 1,476 bp open reading frame encoding 491 amino acid residues with an approximate molecular mass of 52 kda. homologies of the deduced amino acid sequence of cely with the products of the cela, celx, celg and cel5z genes were 92.6, 93.3, 92.6, and 59.1%, respectively. addi ...200919639353
structure of esta esterase from psychrotrophic pseudoalteromonas sp. 643a covalently inhibited by monoethylphosphonate.the crystal structure of the esterase esta from the cold-adapted bacterium pseudoalteromonas sp. 643a was determined in a covalently inhibited form at a resolution of 1.35 a. the enzyme has a typical sgnh hydrolase structure consisting of a single domain containing a five-stranded beta-sheet, with three helices at the convex side and two helices at the concave side of the sheet, and is ornamented with a couple of very short helices at the domain edges. the active site is located in a groove and ...200919724118
[culture optimization and characterization of an alginate-lyase from pseudoalteromonas sp. lj1].the present work aimed to optimize the culture conditions to produce extracellular alginate-lyase by pseudoalteromonas sp. lj1.200919835172
antimicrobial properties of resident coral mucus bacteria of oculina patagonica.the inhibitory properties of the microbial community of the coral mucus from the mediterranean coral oculina patagonica were examined. out of 156 different colony morphotypes that were isolated from the coral mucus, nine inhibited the growth of vibrio shiloi, a species previously shown to be a pathogen of this coral. an isolate identified as pseudoalteromonas sp. was the strongest inhibitor of v. shiloi. several isolates, especially one identified as roseobacter sp., also showed a broad spectrum ...200919191871
molecular phylogeny and modular structure of hybrid nrps/pks gene fragment of pseudoalteromonas sp. nj6-3-2 isolated from marine sponge hymeniacidon perleve.among 12 marine bacterial strains from the china coast that exhibited interesting bioactivity (positive for both antimicrobial and cytotoxic activities), only four strains, namely, nj6-3-1, nj6-3-2, nb-6, and ythm-17, had a ks domain or a domain when screened for pks and nrps genes using a pcr. interestingly, two of these strains belonging to pseudoalteromonas and associated with the marine sponge hymeniacidon perleve were positive for both pks and nrps, whereas the other two strains of pseudoal ...200919349747
sequencing and modular analysis of the hybrid non-ribosomal peptide synthase - polyketide synthase gene cluster from the marine sponge hymeniacidon perleve-associated bacterium pseudoalteromonas sp. strain nj631.in the present study, we sought to confirm a putative non-ribosomal peptide synthase (nrps) - polyketide synthase (pks) gene cluster in marine sponge-associated bacterium with cytotoxic activity and elucidate the gene's structural information. the genomic library of the marine sponge hymeniacidon perleve-associated bacterium pseudoalteromonas sp. strain nj631 was constructed using a pcc1fos fosmid. positive clones that covered the whole gene cluster region of hybrid nrps-pks were selected for sh ...200919370064
diterpenoids from the mediterranean brown alga dictyota sp. evaluated as antifouling substances against a marine bacterial biofilm.four new cyclized diterpenes, one xenicane (1) and three dolabellanes (2-4), were isolated, along with seven previously reported metabolites [3beta-hydroxydilophol (5), dictyols e (6) and c (7), hydroxycrenulide (8), 9-acetoxy-15-hydroxy-1,6-dollabelladiene (9), hydroxyacetyldictyolal (10), and fucoxanthin], from a mediterranean species of dictyota sp. collected in le brusc lagoon (french mediterranean coast). their structures, as well as their relative configurations, were determined through ex ...200919548693
nutrient regime regulates complex transcriptional start site usage within a pseudoalteromonas chitinase gene cluster.the chitinase gene cluster of the marine bacterium pseudoalteromonas sp. s91, chiabc, which produces the major chitinases of this sp., was transcribed as an operon and from each individual gene. chia, chib and chic were found to possess multiple transcriptional start points (tsps), the use of which was determined by the nutrient regime used for s91 growth. in minimal medium containing glutamate, chia, chib and chic each used 3, 1 and 1 tsp, respectively. upon the addition of the chitin monomer n ...200919458654
quantification of water and biomass in small colony variant pao1 biofilms by confocal raman microspectroscopy.the raman spectra, water content, and biomass density of wild-type (wt) pseudomonas aeruginosa pao1, small colony variant (scv) pao1, and pseudoalteromonas sp. ncimb 2021 biofilms were compared in order to determine their variation with strain and species. living, fully submerged biofilms were analyzed in situ by confocal raman microspectroscopy for up to 2 weeks. water to biomass ratios (w/brs), which are the ratios of the o-h stretching vibration of water at 3,450 cm(-1) to the c-h stretching ...200919529929
novel use for the osmolyte trimethylamine n-oxide: retaining the psychrophilic characters of cold-adapted protease deseasin mcp-01 and simultaneously improving its thermostability.the low thermostability of cold-adapted enzymes is a main barrier for their application. a simple and reliable method to improve both the stability and the activity of cold-adapted enzymes is still rare. as a protein stabilizer, the effect of trimethylamine n-oxide (tmao) on a cold-adapted enzyme or protein has not been reported. in this study, effects of tmao on the structure, activity, and stability of a cold-adapted protease, deseasin mcp-01, were studied. deseasin mcp-01 is a new type of sub ...200919255806
detection of uvbr-sensitive and -tolerant bacteria in surface waters of the western north pacific.in order to evaluate the effects of solar ultraviolet radiation (uvr) on eubacterial community composition, we examined the tolerance of eubacterial phylotypes to solar uv radiation in surface waters of the western north pacific during september 2005. bromodeoxyuridine (brdu), a halogenated thymine analogue, was used for labeling newly synthesized dna in proliferating cells. thymine dimers (td), which are specifically formed in dna by biologically harmful ultraviolet b radiation (uvbr; 280-315nm ...200919285879
[biosorption of pb2+ and cu2+ by an exopolysaccharide from the deep-sea psychrophilic bacterium pseudoalteromonas sp. sm9913].biosorption of pb2+ and cu2+ by exopolysaccharide (eps) from the deep-sea psychrophilic bacterium pseudoalteromonas sp. sm9913 was investigated. the influence of eps dosage, ph, equilibrium time and coexisted-ions on adsorption property and the adsorption isotherm of this eps were studied. the results show that the equilibrium adsorption capacity (qe) decreases with the increase of eps dosage. the optimum ph for the adsorption of pb2+ is 4.5-5.5, and for the adsorption of cu2+ is 4.5-6.0. the ad ...200919353881
a novel extracellular phospholipase c purified from a marine bacterium, pseudoalteromonas sp. j937.marine bacterial isolates were screened for phospholipase c (plc) activity on pcy agar plates containing phosphatidylcholine (pc) as substrate. the strain that showed the highest activity on a pcy screening agar plate and a thin-layer chromatography was identified as a strain of pseudoalteromonas and subsequently designated pseudoalteromonas sp. j937. the extracellular plc of the strain j937 was purified to a specific activity of 33 u mg(-1) protein by serial ion exchange and gel filtration colu ...200918784905
nitrogen regulates chitinase gene expression in a marine bacterium.ammonium concentration and nitrogen source regulate promoter activity and use for the transcription of chia, the major chitinase gene of pseudoalteromonas sp. s91 and s91cx, an s91 transposon lacz fusion mutant. the activity of chia was quantified by beta-galactosidase assay of s91cx cultures containing different ammonium concentrations (nh4+; 0, 9.5 or 191 mm) and with different nitrogen sources (n-acetylglucosamine (glcnac) or glutamate (glt)). s91 chia expression was found to depend on both t ...200919440232
analysis of effects induced by a pollock protein hydrolysate on early development, innate immunity and the bacterial community structure of first feeding of atlantic halibut (hippoglossus hippoglossus l.) larvae.a pollock protein hydrolysate was used for enrichment of the live feed offered to halibut larvae from the onset of exogenous feeding and the effects of treatment on selected innate immune parameters studied. the effects of treatment on the bacterial community structure of larvae were furthermore studied using the pcr-dgge method. c3 and lysozyme were identified in larvae already at the onset of first feeding and low concentrations of igm detected at this stage indicate maternal origin. endogenou ...200919465132
cloning, expression and characterization of a new agarase-encoding gene from marine pseudoalteromonas sp.the beta-agarase gene agaa, cloned from a marine bacterium, pseudoalteromonas sp. cy24, consists of 1,359 nucleotides encoding 453 amino acids in a sequence corresponding to a catalytic domain of glycosyl hydrolase family 16 (gh16) and a carbohydrate-binding module type 13 (cbm13). the recombinant enzyme is an endo-type agarase that hydrolyzes beta-1,4-linkages of agarose, yielding neoagarotetraose and neoagarohexaose as the predominant products. in two cleavage patterns, agaa digested the small ...200919504047
biodegradation of crude oil by an arctic psychrotrophic bacterium pseudoalteromomas sp. p29.a psychrotrophic petroleum-degrading bacterium pseudoalteromonas sp. p29 was isolated from marine sediment, which was collected during 2nd chinese arctic scientific expedition. the phenotypic character and biodegradation efficiency on mixed oil or vacuum oil were tested at low temperature. the strain pseudoalteromonas sp. p29 grew in a range of temperature from 5 to 35 degrees c and the optimum temperature was 25 degrees c. gas chromatography analysis indicated that the strain might preferential ...200919543945
molecular analysis of the gene encoding a cold-adapted halophilic subtilase from deep-sea psychrotolerant bacterium pseudoalteromonas sp. sm9913: cloning, expression, characterization and function analysis of the c-terminal ppc domains.only a few cold-adapted halophilic proteases have been reported. here, the gene mcp03 encoding a cold-adapted halophilic protease mcp-03 was cloned from deep-sea psychrotolerant bacterium pseudoalteromonas sp. sm9913, which contains a 2,130-bp orf encoding a novel subtilase precursor. the recombinant mcp-03, expressed in escherichia coli bl21 and purified from fermented broth, is a multi-domain protein with a catalytic domain and two ppc domains. compared to mesophilic subtilisin carlsberg, mcp- ...200919544039
[ftir spectrum and coagulation enhancement of exopolysaccharide secreted by an antarctica bacterium pseudoalteromona sp. bsi20310].bsi20310 exopolysaccharide (bsi20310 eps) was secreted by a bacteria named pseudoalteromonas sp. bsi20310, isolated from antarctic sea ice. crude bsi20310 eps was prepared by precipitation of the culture solution with ethanol, with proteins removed by using chloroform and butanol preparatorily. the results showed that bsi20310 eps improved the fecl3 coagulation performance on synthetic water-soluble dye reactive red x-3b dyeing wastewater, obviously. the optimum coagulation enhancement of bsi203 ...200919950639
cloning, sequence analysis, and expression of gene alypi encoding an alginate lyase from marine bacterium pseudoalteromonas sp. cy24.the alginate lyase encoding gene (alypi) of marine bacterium pseudoalteromonas sp. cy24 was cloned using a battery of pcr techniques. gene alypi was composed of a 1575 bp open reading frame encoding a protein of 57.4 kda containing 524 amino acid residues with a signal peptide of 23 amino acids. the alypi protein was expressed in escherichia coli with a his-tag sequence fused at the c-terminal end and purified to electrophoretic homogeneity using ni-sepharose affinity chromatography. alypi was m ...200919898554
membrane vesicles: a common feature in the extracellular matter of cold-adapted antarctic bacteria.many gram-negative, cold-adapted bacteria from the antarctic environment produce large amounts of extracellular matter, which has potential biotechnology applications. we examined the ultrastructure of extracellular matter from five antarctic bacteria (shewanella livingstonensis nf22(t), shewanella vesiculosa m7(t), pseudoalteromonas sp. m4.2, psychrobacter fozii nf23(t), and marinobacter guineae m3b(t)) by transmission electron microscopy after high-pressure freezing and freeze substitution. al ...201020127086
mechanistic insight into the function of the c-terminal pkd domain of the collagenolytic serine protease deseasin mcp-01 from deep sea pseudoalteromonas sp. sm9913: binding of the pkd domain to collagen results in collagen swelling but does not unwind the collagen triple helix.deseasin mcp-01 is a bacterial collagenolytic serine protease. its catalytic domain alone can degrade collagen, and its c-terminal pkd domain is a collagen-binding domain (cbd) that can improve the collagenolytic efficiency of the catalytic domain by an unknown mechanism. here, scanning electron microscopy (sem), atomic force microscopy (afm), zeta potential, and circular dichroism spectroscopy were used to clarify the functional mechanism of the pkd domain in mcp-01 collagenolysis. the pkd doma ...201020207733
[inhibition of adherence of corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases from marine hydrobiontes].a possibility of adhesion inhibition of corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases of marine hydrobiontes was investigated using alpha-galactosidase from marine bacterium pseudoalteromonas sp. kmm 701, total enzyme preparation and beta-1,3-glucanase from marine fungi chaetomium, total enzyme preparation and beta-1,3-glucanase from marine mollusk littorina kurila, and total enzyme preparation from crystalline style of marine mollusk spisula sachalinensis were u ...201020695214
expression, crystallization and preliminary x-ray analysis of an anomeric inverting agarase from pseudoalteromonas sp. cy24.agab from pseudoalteromonas sp. cy24 is a novel agarase that hydrolyzes agarose to generate products with inverted anomeric configuration and that has been proposed to have a larger catalytic cleft than other β-agarases. here, the expression, purification, crystallization and data collection of agab in both wild-type and selenomethionine-substituted forms is described. the crystals of wild-type agab diffracted to 1.97 å resolution and belonged to space group c222(1). the selenomethionine derivat ...201021139213
influence of bacterial lysate quality on growth of two bacterioplankton species.all physico-chemical parameters that affect bacterial growth rate will also affect bacterial molecular composition, which in turn influences the chemical composition of bacterial lysate and its turnover rate in the ecosystem. to produce qualitatively different lysates, vibrio sp. cells were grown under different ph, salt, or temperature conditions in rich growth media and then washed and lysed by autoclaving. both the absolute concentrations and the ratios between elements in the lysates varied ...201019582501
molecular characterization and therapeutic potential of a marine bacterium pseudoalteromonas sp. kmm 701 alpha-galactosidase.an alpha-galactosidase capable of converting b red blood cells into the universal blood type cells at the neutral ph was produced by a novel obligate marine bacterium strain kmm 701 (vkm b-2135 d). the organism is heterotrophic, aerobic, and halophilic and requires na+ ions and temperature up to 34 degrees c for its growth. the strain has a unique combination of polysaccharide-degrading enzymes. its single intracellular alpha-galactosidase exceeded other glycoside hydrolases in the level of expr ...201019629597
a novel beta-agarase with high ph stability from marine agarivorans sp. lq48.a novel endo-type beta-agarase gene, agaa, was cloned from a newly isolated marine bacterium, agarivorans sp. lq48. it encodes a protein of 457 amino acids with a calculated molecular mass of 51.2 kda. the deduced protein contains a typical n-terminal signal peptide of 25 amino acid residues, followed by a catalytic module, which is homologous to that of glycoside hydrolase family 16. a sequence similar to a carbohydrate-binding module is found in the c-terminal region of the enzyme. the overall ...201019484308
discovery and characterization of a distinctive exo-1,3/1,4-{beta}-glucanase from the marine bacterium pseudoalteromonas sp. strain bb1.marine bacteria residing on local red, green, and brown seaweeds were screened for exo-1,3-β-glucanase (exop) activity. of the 90 bacterial species isolated from 32 seaweeds, only one, a pseudoalteromonas sp., was found to display such activity. it was isolated from a durvillaea sp., a brown kelp known to contain significant amounts of the storage polysaccharide laminarin (1,3-β-d-glucan with some 1,6-β branching). four chromatographic steps were utilized to purify the enzyme (exop). chymotrypti ...201020729316
highly brominated antimicrobial metabolites from a marine pseudoalteromonas sp.extracts of a marine pseudoalteromonas sp. (cmmed 290) isolated from the surface of a nudibranch collected in kaneohe bay, oahu, displayed significant antimicrobial activity against methicillin-resistant staphylococcus aureus. bioassay-guided fractionation of the lipophilic extract led to the isolation and structure elucidation of two new highly brominated compounds, 2,3,5,7-tetrabromobenzofuro[3,2-b]pyrrole (1) and 4,4',6-tribromo-2,2'-biphenol (2). in addition, we have identified the known com ...201020973551
cloning, purification and biochemical characterization of beta agarase from the marine bacterium pseudoalteromonas sp. ag4.a gene (agrp) encoding a beta-agarase from pseudoalteromonas sp. ag4 was cloned and expressed in escherichia coli. the agrp primary structure consists of an 870-bp open reading frame (orf) encoding 290 amino acids (aa). the predicted molecular mass and isoelectric point were determined at 33 kda and 5.9, respectively. the signal peptide was predicted to be 21 aa. the deduced aa sequence showed 98.6% identity to beta-agarase from pseudoalteromonas atlantica. the recombinant protein was purified a ...201020213114
antibiofilm activity of the marine bacterium pseudoalteromonas sp. strain 3j6.biofilm formation results in medical threats or economic losses and is therefore a major concern in a variety of domains. in two-species biofilms of marine bacteria grown under dynamic conditions, pseudoalteromonas sp. strain 3j6 formed mixed biofilms with bacillus sp. strain 4j6 but was largely predominant over paracoccus sp. strain 4m6 and vibrio sp. strain d01. the supernatant of pseudoalteromonas sp. 3j6 liquid culture (sn(3j6)) was devoid of antibacterial activity against free-living paraco ...201020363799
[molecular cloning, gene expression and characterization of purine nucleoside phosphorylase from pseudoalteromonas sp. xm2107].purine nucleoside phosphorylase (pnp, ec 2.4.2.1) is an important enzyme which is applied in nucleoside medication and intermediate biosynthesis. in this paper, we aimed to obtain the pnp gene from cold-adapted marine bacterium pseudoalteromonas sp. xm2107 and study the characteristics of enzyme for applying in nucleoside medication and intermediate biosynthesis.201020387465
domains iii and i-2{alpha}, at the entrance of the binding cleft, play an important role in cold adaptation of the periplasmic dipeptide-binding protein (dppa) from the deep-sea psychrophilic bacterium pseudoalteromonas sp. strain sm9913.the peptide transporter from a cold-adapted bacterium has never been reported. in the present study, the dpp operon from the psychrophilic bacterium pseudoalteromonas sp. strain sm9913 was cloned and analyzed. the dipeptide binding protein dppa of sm9913 was overexpressed in escherichia coli, and its cold adaptation characteristics were studied. the recombinant dppa of sm9913 (psdppa) displayed the highest ligand-binding affinity at 15 degrees c, whereas the recombinant dppa of e. coli (ecdppa) ...201020453143
identification of the pathogens associated with skin ulceration and peristome tumescence in cultured sea cucumbers apostichopus japonicus (selenka).the aquaculture of sea cucumbers apostichopus japonicus (selenka) has developed rapidly in china in recent years, but is increasingly affected by diseases such as skin ulceration and peristome tumescence. previous studies on the pathogens causing these diseases focused largely on bacterial causes. in december 2008, we isolated four dominant bacterial species from lesions present in a. japonicus with the aforementioned diseases, from a farm in yangkou (qingdao, china). with two of these bacterial ...201020561977
Refresh
firstprev
12
nextlast
Displaying items 1 - 100 of 116