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 ... | 2007 | 17600056 |
the regulator cdss/cdsr two-component system modulates expression of genes involved in chitin degradation of pseudoalteromonas piscicida strain o-7. | pseudoalteromonas piscicida strain o-7 (formerly alteromonas sp. strain o-7) is an efficient degrader of chitin in the marine environment. the chitinolytic system of the strain consists of many enzymes induced by n-acetylglucosamine (glcnac). this paper reports that cdsr, which is a response regulator of cdss/cdsr two-component signal transduction system, is bound to near the promoter region of glcnac-induced apriv gene. the cdsr protein as a response regulator was transphosphorylated by the cds ... | 2007 | 17634925 |
the linker region plays a key role in the adaptation to cold of the cellulase from an antarctic bacterium. | the psychrophilic cellulase, cel5g, from the antarctic bacterium pseudoalteromonas haloplanktis is composed of a catalytic module (cm) joined to a carbohydrate-binding module (cbm) by an unusually long, extended and flexible linker region (lr) containing three loops closed by three disulfide bridges. to evaluate the possible role of this region in cold adaptation, the lr was sequentially shortened by protein engineering, successively deleting one and two loops of this module, whereas the last di ... | 2007 | 17635108 |
analysis of a genomic island housing genes for dna s-modification system in streptomyces lividans 66 and its counterparts in other distantly related bacteria. | the complete sequence (92 770 bp) of a genomic island (gi) named slg from streptomyces lividans 66, encoding a novel dna s-modification system (dnd), was determined. its overall g+c content was 67.8%, lower than those of three sequenced streptomyces genomes. among 85 predicted open reading frames (orfs) in slg, 22 orfs showed little homology with previously known proteins. slg displays a mosaic structure composed of four modules, indicative of multiple recombination events in its formation. spon ... | 2007 | 17640271 |
inhibition of fouling by marine bacteria immobilised in kappa-carrageenan beads. | antifouling solutions that leave little or no impact in the world's oceans are constantly being sought. this study employed the immobilisation of the antifouling bacterium pseudoalteromonas tunicata in kappa-carrageenan to demonstrate how a surface may be protected from fouling by bacteria, i.e. a 'living paint'. attempts so far to produce a 'living paint' have been limited in both longevity of effectiveness and demonstration of applicability, most noticeably regarding the lack of any field data ... | 2007 | 17653938 |
effect of biofilm formation by pseudoalteromonas spongiae on induction of larval settlement of the polychaete hydroides elegans. | the effects of culture conditions and chloramphenicol treatment on the induction of the marine bacterium pseudoalteromonas spongiae to larval settlement of hydroides elegans were investigated. the results showed that p. spongiae cells grown in the medium containing both yeast extract and peptone (yp-grown p. spongiae) was highly inductive to larval settlement, whereas p. spongiae cells grown in the medium containing only peptone (p-grown p. spongiae) or yp-grown p. spongiae cells treated with ch ... | 2007 | 17704279 |
polymyxin b induces lysis of marine pseudoalteromonads. | polymyxin b (pmb) is a cationic antibiotic that interacts with the envelopes of gram-negative bacterial cells. the therapeutic use of pmb was abandoned for a long time due to its undesirable side effects; however, the spread of resistance to currently used antibiotics has forced the reevaluation of pmb for clinical use. previous studies have used enteric bacteria to examine the mode of pmb action, resulting in a somewhat limited understanding of this process. this study examined the effects of p ... | 2007 | 17709471 |
the noncatalytic triad of alpha-amylases: a novel structural motif involved in conformational stability. | chloride-activated alpha-amylases contain a noncatalytic triad, independent of the glycosidic active site, perfectly mimicking the catalytic triad of serine-proteases and of other active serine hydrolytic enzymes. mutagenesis of glu, his, and ser residues in various alpha-amylases shows that this pattern is a structural determinant of the enzyme conformation that cannot be altered without losing the intrinsic stability of the protein. (1)h-(15)n nmr spectra of a bacterial alpha-amylase reveal pr ... | 2008 | 17729287 |
biodegradative potential and characterization of psychrotolerant polychlorinated biphenyl-degrading marine bacteria isolated from a coastal station in the terra nova bay (ross sea, antarctica). | antarctic marine bacteria were screened for their ability to degrade polychlorinated biphenyls (pcb) as the sole carbon and energy source at both 4 degrees c and 15 degrees c. pcb-degrading isolates (7.1%) were identified by sequencing their 16s rdna as pseudoalteromonas, psychrobacter and arthrobacter members. one representative isolate per genera was selected for evaluating the biodegradative potential under laboratory scale and phenotypically characterized. removal of individual pcb congeners ... | 2007 | 17854841 |
evaluation of the activity of the sponge metabolites avarol and avarone and their synthetic derivatives against fouling micro- and macroorganisms. | the sesquiterpene hydroquinone avarol (1) was isolated from the marine sponge dysidea avara, whereas the corresponding quinone, avarone (2), was obtained by oxidation of avarol, and the significantly more lipophilic compounds [3'-(p-chloro-phenyl)avarone (3), 3',4'-ethylenedithioavarone (4), 4'-isopropylthioavarone (5), 4'-tert-butylthioavarone (6), 4'-propylthioavarone (7), 4'-octylthioavarone (8)] were obtained by nucleophilic addition of thiols or p-chloroaniline to avarone. all these compoun ... | 2007 | 17873837 |
total syntheses of tambjamines c, e, f, g, h, i and j, be-18591, and a related alkaloid from the marine bacterium pseudoalteromonas tunicata. | the acetate salts of tambjamines c, e, and f (2-4, respectively), as well as those of the related alkaloids be-18591 (5) and 6, have been prepared by treatment of bipyrrole aldehyde 16 with the relevant amine in the presence of acetic acid. the 5'-bromo-analogue, 30, of compound 16 has also been prepared and used to obtain the acetate salts of tambjamines g, h, i, and j (8-11 respectively). | 2007 | 17963401 |
low densities of epiphytic bacteria from the marine alga ulva australis inhibit settlement of fouling organisms. | bacteria that produce inhibitory compounds on the surface of marine algae are thought to contribute to the defense of the host plant against colonization of fouling organisms. however, the number of bacterial cells necessary to defend against fouling on the plant surface is not known. pseudoalteromonas tunicata and phaeobacter sp. strain 2.10 (formerly roseobacter gallaeciensis) are marine bacteria often found in association with the alga ulva australis and produce a range of extracellular inhib ... | 2007 | 17965210 |
isolation and characterization of two groups of novel marine bacteria producing violacein. | thirteen strains of novel marine bacteria producing a purple pigment were isolated from the pacific coast of japan. they were divided into two groups based on their 16s ribosomal rna gene sequences, and both groups of bacteria belonged to the genus pseudoalteromonas. the uv-visible spectrum of the pigment was identical to those of violacein, a pigment produced by several species of bacteria including chromobacterium violaceum, an opportunistic pathogen. further analysis of the chemical structure ... | 2008 | 17968625 |
[characteristics of adhesion of epiphytic bacteria on leaves of the seagrass zostera marina and on abiotic surfaces]. | a comparative study of the adhesion of epiphytic bacteria and marine free-living, saprophytic, and pathogenic bacteria on seagrass leaves and abiotic surfaces was performed to prove the occurrence of true epiphytes of zostera marina and to elucidate the bacterium-plant symbiotrophic relationships. it was shown that in the course of adhesion to the seagrass leaves of two taxonomically different bacteria, cytophaga sp. kmm 3552 and pseudoalteromonas citrea kmm 461, isolated from the seagrass surfa ... | 2007 | 17974207 |
cholest-4-en-3-one-delta 1-dehydrogenase, a flavoprotein catalyzing the second step in anoxic cholesterol metabolism. | the anoxic metabolism of cholesterol was studied in the denitrifying bacterium sterolibacterium denitrificans, which was grown with cholesterol and nitrate. cholest-4-en-3-one was identified before as the product of cholesterol dehydrogenase/isomerase, the first enzyme of the pathway. the postulated second enzyme, cholest-4-en-3-one-delta(1)-dehydrogenase, was partially purified, and its n-terminal amino acid sequence and tryptic peptide sequences were determined. based on this information, the ... | 2008 | 17993555 |
isolation and structure elucidation of a novel yellow pigment from the marine bacterium pseudoalteromonas tunicata. | the marine environment is a major source for many novel natural compounds. a new yellow pigment has been isolated from the marine bacterium p. tunicata and identified as a new member of the tambjamine class of compounds. the structural identification was achieved by a combination of 1d and 2d-nmr spectroscopy and high resolution mass spectrometry data. | 2005 | 18007521 |
molecular determination of oxytetracycline-resistant bacteria and their resistance genes from mariculture environments of china. | to assess the diversity of antibiotic-resistant bacteria and their resistance genes in typical maricultural environments. | 2007 | 18045442 |
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 ... | 2008 | 18058451 |
[application of the complex of dna with the congo red anionic diazo dye for detection of nuclease-producing colonies of marine bacteria]. | this study was aimed at the development of a method for detection of colonies of nuclease-secreting marine bacteria. the bal nuclease-producing marine bacterium pseudoalteromonas espejiana bal-31 was used as the test object. a new method was developed involving the congo red (cr) anionic dye. the p. espejiana culture was plated on nutrient agar with cr and denatured dna. in such media. cr was found to form complexes with dna. after two days of incubation at 30 degrees c, halos were found around ... | 2007 | 18069327 |
composition and distribution of carrabiose moieties in hybrid kappa-/iota-carrageenans using carrageenases. | hybrid kappa/iota-carrageeans extracted from gigartina skottsbergii, chondracanthus chamissoï, and chondrus crispus were incubated with pseudoalteromonas carrageenovora kappa-carrageenase and alteromonas fortis iota-carrageenase. the degradation products as well as the resistant fraction were fully characterized by chromatography, nmr, and mass spectrometry. the low percentage of degradation observed after treatment by the iota-carrageenase suggests that long segments of iota-carrabiose or block ... | 2008 | 18081251 |
genetics for pseudoalteromonas provides tools to manipulate marine bacterial virus pm2. | the genetic manipulation of marine double-stranded dna (dsdna) bacteriophage pm2 (corticoviridae) has been limited so far. the isolation of an autonomously replicating dna element of pseudoalteromonas haloplanktis tac125 and construction of a shuttle vector replicating in both escherichia coli and pseudoalteromonas enabled us to design a set of conjugative shuttle plasmids encoding trna suppressors for amber mutations. using a host strain carrying a suppressor plasmid allows the introduction and ... | 2008 | 18083813 |
preliminary characterization of exopolysaccharides produced by a marine biofilm-forming bacterium pseudoalteromonas ruthenica (sbt 033). | the major objective of the present study was the partial characterization of the exopolysaccharides (eps) produced by a marine biofilm-forming bacterium pseudoalteromonas ruthenica under shake culture conditions. | 2008 | 18086196 |
cryoprotective properties of exopolysaccharide (p-21653) produced by the antarctic bacterium, pseudoalteromonas arctica kopri 21653. | twenty-five bacterial strains that secrete mucous materials were isolated from sediment obtained from king george island, antarctica. seven of these strains proved capable of producing cryoprotective exopolysaccharides. the strain kopri 21653 was selected for the further study of an anti-ice-nucleating polysaccharide (anp), which originated from a polar region. kopri 21653 was identified as pseudoalteromonas arctica as the result of 16s rrna analysis. the exopolysaccharide, p-21653, was purified ... | 2007 | 18176533 |
"pseudoalteromonas januaria" sut 11 as the source of rare lipodepsipeptides. | the marine bacterium "pseudoalteromonas januaria" sut 11 isolated from a seawater sample produced the rare cell-bound cyclic lipodepsipeptides a/a', b/b', and c/c'. the matrix-assisted laser desorption/ionization mass spectra indicated that one bromine atom presented in the peptides b/b' and c/c', whereas the component a/a' contained no bromine atom. the acyldepsipeptides a/a'-c/c' have an identical amino acid sequence, thr-val-asn-asn-leu/allo-ile, but differed in c-terminal amino acid and acyl ... | 2008 | 18180994 |
potential for luxs related signalling in marine bacteria and production of autoinducer-2 in the genus shewanella. | the autoinducer-2 (ai-2) group of signalling molecules are produced by both gram positive and gram negative bacteria as the by-product of a metabolic transformation carried out by the luxs enzyme. they are the only non species-specific quorum sensing compounds presently known in bacteria. the luxs gene coding for the ai-2 synthase enzyme was found in many important pathogens. here, we surveyed its occurrence in a collection of 165 marine isolates belonging to abundant marine phyla using conserve ... | 2008 | 18215278 |
microbial carbohydrate esterases in cold adapted environments. | psychrophiles produce cold-evolved enzymes that display a high catalytic efficiency, associated with a low thermal stability. in recent years, these enzymes have attracted the attention of scientists because of their peculiar properties that render them particularly useful in investigating the relationship existing between enzyme stability and flexibility on one hand, and enzyme activity on the other hand. among these enzymes, the esterases, and particularly the feruloyl esterases, have potentia ... | 2008 | 18242884 |
development of an improved pseudoalteromonas haloplanktis tac125 strain for recombinant protein secretion at low temperature. | abstract: | 2008 | 18257924 |
lipl32 is an extracellular matrix-interacting protein of leptospira spp. and pseudoalteromonas tunicata. | lipl32 is the major outer membrane protein in pathogenic leptospira. it is highly conserved throughout pathogenic species and is expressed in vivo during human infection. while these data suggest a role in pathogenesis, a function for lipl32 has not been defined. outer membrane proteins of gram-negative bacteria are the first line of molecular interaction with the host, and many have been shown to bind host extracellular matrix (ecm). a search for leptospiral ecm-interacting proteins identified ... | 2008 | 18285490 |
effect of incubation temperature on growth parameters of pseudoalteromonas antarctica nf and its production of extracellular polymeric substancesdagger. | to evaluate the effect of temperature on growth parameters and on extracellular polymeric substance (eps) production for pseudoalteromonas antarctica nf(3). | 2008 | 18298522 |
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 ... | 2008 | 18299797 |
glutathionylation of the iron superoxide dismutase from the psychrophilic eubacterium pseudoalteromonas haloplanktis. | our previous work showed that the adduct between beta-mercaptoethanol and the single cysteine residue (cys57) in superoxide dismutase from the psychrophilic eubacterium pseudoalteromonas haloplanktis (phsod) reduces the enzyme inactivation by peroxynitrite. in this work, immunoblotting experiments prove that peroxynitrite inactivation of phsod involves formation of nitrotyrosine residue(s). in order to study the role of cys57 as a redox-sensor residue modifiable by cellular thiols, a recombinant ... | 2008 | 18328273 |
rapid chemotactic response enables marine bacteria to exploit ephemeral microscale nutrient patches. | because ocean water is typically resource-poor, bacteria may gain significant growth advantages if they can exploit the ephemeral nutrient patches originating from numerous, small sources. although this interaction has been proposed to enhance biogeochemical transformation rates in the ocean, it remains questionable whether bacteria are able to efficiently use patches before physical mechanisms dissipate them. here we show that the rapid chemotactic response of the marine bacterium pseudoalterom ... | 2008 | 18337491 |
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 ... | 2008 | 18353634 |
phylogenetic and enzymatic diversity of deep subseafloor aerobic microorganisms in organics- and methane-rich sediments off shimokita peninsula. | "a meta-enzyme approach" is proposed as an ecological enzymatic method to explore the potential functions of microbial communities in extreme environments such as the deep marine subsurface. we evaluated a variety of extra-cellular enzyme activities of sediment slurries and isolates from a deep subseafloor sediment core. using the new deep-sea drilling vessel "chikyu", we obtained 365 m of core sediments that contained approximately 2% organic matter and considerable amounts of methane from offs ... | 2008 | 18368287 |
cloning, expression and physicochemical characterization of a di-heme cytochrome c (4) from the psychrophilic bacterium pseudoalteromonas haloplanktis tac 125. | the 20-kda di-heme cytochrome c (4) from the psycrophilic bacterium pseudoalteromonas haloplanktis tac 125 was cloned and expressed in escherichia coli and investigated through uv-vis and (1)h nmr spectroscopies and protein voltammetry. the model structure was computed using the x-ray structure of pseudomonas stutzeri cytochrome c (4) as a template. the protein shows unprecedented properties within the cytochrome c (4) family, including (1) an almost nonpolar surface charge distribution, (2) the ... | 2008 | 18386080 |
synthesis and proteomic activity evaluation of a new isotope-coded affinity tagging (icat) reagent. | during recent years, quantitative proteome profiling has taken advantage of incorporating the traditional stable isotope dilution analysis into global scale or discovery-based proteomic experiments that use mass spectrometers as detectors to allow the pairwise study of differently expressed proteins. quantitative protein analysis by means of the isotope-coded affinity tag (icat) method and tandem mass spectrometry (ms) enables the pairwise comparison of protein expression levels in biological sa ... | 2008 | 18407682 |
the cold-active lip1 lipase from the antarctic bacterium pseudoalteromonas haloplanktis tac125 is a member of a new bacterial lipolytic enzyme family. | the genome of the antarctic bacterium pseudoalteromonas haloplanktis tac125 was searched for the presence of genes encoding ester-hydrolysing enzymes. amongst the others, the gene pshaa0051 coding for a putative secreted esterase/lipase was selected. the psychrophilic gene was cloned, functionally over-expressed in p. haloplanktis tac125, and the recombinant product (after named phtac125 lip1) was purified. phtac125 lip1 was found to be associated to the outer membrane and exhibited higher enzym ... | 2008 | 18437283 |
biodiversity of polycyclic aromatic hydrocarbon-degrading bacteria from deep sea sediments of the middle atlantic ridge. | the bacteria involved in the biodegradation of polycyclic aromatic hydrocarbons (pahs) in deep sea subsurface environments are largely unknown. in order to reveal their biodiversity, sediments from 2.2 m under the bottom surface at a water depth of 3542 m were sampled on the middle atlantic ridge with a gravity column sampler. the sediments were promptly enriched with either crude oil or a mixture of pahs (naphthalene, phenanthrene and pyrene) as the sole carbon source, and further enriched with ... | 2008 | 18445026 |
molecular structure of endotoxins from gram-negative marine bacteria: an update. | marine bacteria are microrganisms that have adapted, through millions of years, to survival in environments often characterized by one or more extreme physical or chemical parameters, namely pressure, temperature and salinity. the main interest in the research on marine bacteria is due to their ability to produce several biologically active molecules, such as antibiotics, toxins and antitoxins, antitumor and antimicrobial agents. nonetheless, lipopolysaccharides (lpss), or their portions, from g ... | 2007 | 18463721 |
bioactive compound synthetic capacity and ecological significance of marine bacterial genus pseudoalteromonas. | the genus pseudoalteromonas is a marine group of bacteria belonging to the class gammaproteobacteria that has come to attention in the natural product and microbial ecology science fields in the last decade. pigmented species of the genus have been shown to produce an array of low and high molecular weight compounds with antimicrobial, anti-fouling, algicidal and various pharmaceutically-relevant activities. compounds formed include toxic proteins, polyanionic exopolymers, substituted phenolic a ... | 2007 | 18463726 |
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. ... | 2008 | 18468645 |
crystallization and preliminary x-ray diffraction studies of a psychrophilic iron superoxide dismutase from pseudoalteromonas haloplanktis. | the antarctic eubacterium pseudoalteromonas haloplanktis (ph) produces a cold-active iron superoxide dismutase (sod). phsod is a homodimeric enzyme, that displays a high catalytic activity even at low temperature. using hanging-drop vapour-diffusion technique, phsod has been successfully crystallized in two different crystal forms. both crystal forms are monoclinic with space group p2(1) and diffract to 2.1 a resolution. form i has unit-cell parameters a=45.49a b=103.63a c=50.37a beta=108.2 degr ... | 2008 | 18473957 |
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. | 2008 | 18489561 |
hydrogen peroxide linked to lysine oxidase activity facilitates biofilm differentiation and dispersal in several gram-negative bacteria. | the marine bacterium pseudoalteromonas tunicata produces an antibacterial and autolytic protein, alpp, which causes death of a subpopulation of cells during biofilm formation and mediates differentiation, dispersal, and phenotypic variation among dispersal cells. the alpp homologue (loda) in the marine bacterium marinomonas mediterranea was recently identified as a lysine oxidase which mediates cell death through the production of hydrogen peroxide. here we show that alpp in p. tunicata also act ... | 2008 | 18502869 |
the macromolecule with antimicrobial activity synthesized by pseudoalteromonas luteoviolacea strains is an l-amino acid oxidase. | two purple pigmented bacterial strains, cpmor-1 and cpmor-2, have been newly isolated from the mediterranean sea. 16s rna sequencing and phenotypic characteristics indicate that they belong to the species pseudoalteromonas luteoviolacea. the synthesis of macromolecules with antimicrobial activity is a capacity described in many strains of this species although the nature of those macromolecules has not been reported up to now. the search for antimicrobial compounds in the two new strains describ ... | 2008 | 18504575 |
short peptide induces an "uncultivable" microorganism to grow in vitro. | microorganisms comprise the bulk of biodiversity, but only a small fraction of this diversity grows on artificial media. this phenomenon was noticed almost a century ago, repeatedly confirmed, and termed the "great plate count anomaly." advances in microbial cultivation improved microbial recovery but failed to explain why most microbial species do not grow in vitro. here we show that at least some of such species can form domesticated variants capable of growth on artificial media. we also pres ... | 2008 | 18515474 |
histopathology of antarctic krill, euphausia superba, bearing black spots. | small black spots have been noticed on the cephalothorax of antarctic krill, euphausia superba, since january, 2001. to study the nature of the black spots, the krill were sampled in the winter of 2003, 2006, and 2007 in the south georgia region, the antarctic ocean. histological observations revealed that the black spots were melanized nodules that were composed of hemocytes surrounding either bacteria or amorphous material. in the 2007 samples, 42% of the krill had melanized nodules. most of t ... | 2008 | 18534613 |
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 ... | 2008 | 18552188 |
[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. | 2008 | 18590244 |
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. | 2008 | 18603795 |
a quick in vitro pathway from prokaryotic genomic libraries to enzyme discovery. | screening of prokaryotic genomes in order to identify enzymes with a desired catalytic activity can be performed in vivo in bacterial cells. we propose a strategy of in vitro expression screening of large prokaryotic genomic libraries based on escherichia coli cell-free transcription-translation systems. because cell-based expression may be limited by poor yield or protein misfolding, cell-free expression systems may be advantageous in permitting a more comprehensive screen under conditions opti ... | 2008 | 18611168 |
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 ... | 2008 | 18611409 |
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 ... | 2008 | 18617185 |
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 ... | 2008 | 18663413 |
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 ... | 2008 | 18669056 |
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 ... | 2008 | 18700165 |
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. | 2008 | 18720840 |
pseudoalteromonas arctica sp. nov., an aerobic, psychrotolerant, marine bacterium isolated from spitzbergen. | a novel aerobic, psychrotolerant marine bacterium was isolated at 4 degrees c from seawater samples collected from spitzbergen in the arctic. the strain was a polar-flagellated, gram-negative bacterium that grew optimally at 10-15 degrees c and ph 7-8 in media containing 2-3% nacl (w/v), using various carbohydrates and organic acids as substrates. the main fatty acid components included 16:0 (12.7% of total fatty acids), straight-chain saturated fatty acid methyl ester (fame) and 16:1omega7c (40 ... | 2008 | 18768597 |
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 ... | 2009 | 18784905 |
analysis of the pseudoalteromonas tunicata genome reveals properties of a surface-associated life style in the marine environment. | colonisation of sessile eukaryotic host surfaces (e.g. invertebrates and seaweeds) by bacteria is common in the marine environment and is expected to create significant inter-species competition and other interactions. the bacterium pseudoalteromonas tunicata is a successful competitor on marine surfaces owing primarily to its ability to produce a number of inhibitory molecules. as such p. tunicata has become a model organism for the studies into processes of surface colonisation and eukaryotic ... | 2008 | 18813346 |
purification and characterization of antibacterial substances produced by a marine bacterium pseudoalteromonas haloplanktis strain. | to purify and characterize compounds with antimicrobial activity from pseudoalteromonas haloplanktis inhibition (inh) strain. | 2008 | 18828792 |
a 2-substituted prodiginine, 2-(p-hydroxybenzyl)prodigiosin, from pseudoalteromonas rubra. | in the course of work aimed at the discovery of new pharmaceutical lead compounds from marine bacteria, a lipophilic extract of the bacterium pseudoalteromonas rubra displayed significant cytotoxicity against skov-3, a human ovarian adenocarcinoma cell line. bioassay-directed fractionation of this extract resulted in the isolation of a series of known and new prodiginine-type azafulvenes. the structure of the major metabolite was elucidated by interpretation of spectroscopic data as a 2-substitu ... | 2008 | 18922034 |
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 ... | 2008 | 18977758 |
selective control of the prorocentrum minimum harmful algal blooms by a novel algal-lytic bacterium pseudoalteromonas haloplanktis afmb-008041. | in this study, we examined the algal-lytic activities and biological control mechanisms of pseudoalteromonas haloplanktis afmb-08041, which was isolated from surface seawater obtained at masan bay in korea. in addition, we assessed whether afmb-08041 could be used as a biocontrol agent to regulate harmful dinoflagellate prorocentrum minimum. from these experiments, we found that the inoculation of afmb-08041 at a final density of 2.5 x 10(4) cfu ml(-1) caused p. minimum cells to degrade (>90%) w ... | 2009 | 19048341 |
resource patch formation and exploitation throughout the marine microbial food web. | exploitation of microscale (microm-mm) resource patches by planktonic microorganisms may influence oceanic trophodynamics and nutrient cycling. however, examinations of microbial behavior within patchy microhabitats have been precluded by methodological limitations. we developed a microfluidic device to generate microscale resource patches at environmentally realistic spatiotemporal scales, and we examined the exploitation of these patches by marine microorganisms. we studied the foraging respon ... | 2009 | 19053839 |
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 ... | 2008 | 19069841 |
engineered marine antarctic bacterium pseudoalteromonas haloplanktis tac125: a promising micro-organism for the bioremediation of aromatic compounds. | the recombinant antarctic pseudoalteromonas haloplanktis tac125 (p. haloplanktis tac/tou) expressing toluene-o-xylene monooxygenase (tomo) can efficiently convert several aromatic compounds into their corresponding catechols in a broad range of temperature. when the genome of p. haloplanktis tac125 was analysed in silico, the presence of a dna sequence coding for a putative laccase-like protein was revealed. it is well known that bacterial laccases are able to oxidize dioxygenated aromatic compo ... | 2009 | 19120609 |
characterisation of an extracellular vibriolysin of the fish pathogen moritella viscosa. | moritella viscosa causes winter ulcer disease in salmonids. the aim of the present work was to isolate and partially characterise an extracellular peptidase from m. viscosa, and to study its role in virulence. the peptidase, termed mvp1, was a 38-kda metallopeptidase produced in late exponential growth. the optimum temperature for mvp1 was 40 degrees c, but the enzyme was active over a broad range of temperatures. mvp1 was non-lethal to salmon at concentrations up to 0.22microg/g fish, but extra ... | 2009 | 19147307 |
production of oligosaccharide from alginate using pseudoalteromonas agarovorans. | a marine bacterium was isolated from seawater near the korean south coast for efficient saccharification from alginate. based on 16s rdna sequence, the isolated strain was identified as pseudoalteromonas agarovorans. various environmental factors affecting saccharification of alginate using p. agarovorans cho-12 have been investigated in flask cultures. the optimum concentration of sugar was obtained at 30 rpm and 29 degrees c. among various nacl concentrations, when nacl concentration was incre ... | 2009 | 19160071 |
[enrichment and diversity analyis of arsenite-resistant bacteria in deep sea sediment samples from southwest indian ocean ridge]. | the aim of this study was to assess the diversity of arsenite-resistant bacteria in deep sea sediment of the southwest indian ocean ridge. | 2008 | 19160816 |
coral mucus-associated bacteria: a possible first line of defense. | interactions among microorganisms found in coral mucus can be either symbiotic or competitive. it has been hypothesized that microbial communities found on the surface of coral play a role in coral holobiont defense, possibly through production of antimicrobial substances. selected microorganisms isolated from the mucus layer of a number of coral species were grown using agar-plating techniques. screening for antimicrobial substances was performed using overlay and drop techniques, employing sev ... | 2009 | 19161430 |
co-immunopurification of multiprotein complexes containing rna-degrading enzymes. | co-immunopurification is a classical technique in which antiserum raised against a specific protein is used to purify a multiprotein complex. we describe work from our laboratory in which co-immunopurification was used to characterize the rna degradosome of escherichia coli, a multiprotein complex involved in rna processing and mrna degradation. polyclonal rabbit antibodies raised against either rnase e or pnpase, two rna degrading enzymes in the rna degradosome, were used in co-immunopurificati ... | 2008 | 19161838 |
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 ... | 2009 | 19191871 |
physical state of kappa-carrageenan modulates the mode of action of kappa-carrageenase from pseudoalteromonas carrageenovora. | pseudoalteromonas carrageenovora kappa-carrageenase is a glycoside hydrolase involved in the bioconversion of carrageenans. carrageenans are sulfated galactans that are densely packed in red algal cell walls. previous crystallographic investigations revealed that the active site of kappa-carrageenase has a tunnel-shaped topology, suggesting a processive mode of action for this enzyme. to biochemically characterize the enzymatic depolymerization of kappa-carrageenan, soluble and solid substrates ... | 2009 | 19196238 |
isolation, phylogenetic analysis and screening of marine mollusc-associated bacteria for antimicrobial, hemolytic and surface activities. | this study was undertaken to survey culturable heterotrophic bacteria associated with the marine ark shell anadara broughtoni inhabiting in the sea of japan, and to test isolates for their antimicrobial, hemolytic and surface activities with an emphasis on low-molecular-weight metabolites search. a total of 149 strains were isolated and identified phenotypically. a total of 27 strains were selected to be investigated phylogenetically by 165 rrna gene sequence analysis. the most bacteria were aff ... | 2008 | 19216104 |
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 ... | 2009 | 19255806 |
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 ... | 2009 | 19285879 |
diversity of both the cultivable protease-producing bacteria and their extracellular proteases in the sediments of the south china sea. | protease-producing bacteria are known to play an important role in degrading sedimentary particular organic nitrogen, and yet, their diversity and extracellular proteases remain largely unknown. in this paper, the diversity of the cultivable protease-producing bacteria and their extracellular proteases in the sediments of the south china sea was investigated. the richness of the cultivable protease-producing bacteria reached 10(6) cells/g in all sediment samples. analysis of the 16s rrna gene se ... | 2009 | 19301066 |
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 ... | 2008 | 19325731 |
anti-methicillin-resistant staphylococcus aureus (mrsa) activity of mc21-b, an antibacterial compound produced by the marine bacterium pseudoalteromonas phenolica o-bc30t. | the aim of this study was to purify, characterise and evaluate the in vitro activity of mc21-b, an antibiotic produced by the marine bacterium pseudoalteromonas phenolica o-bc30(t). mc21-b was purified by sequential silica and cosmosil chromatography followed by high-performance liquid chromatography (hplc). the chemical structure of mc21-b was determined by ultraviolet, infrared, electron impact mass and nuclear magnetic resonance spectrometric analyses. to evaluate its antibacterial activity, ... | 2009 | 19329285 |
evaluation of various metallic coatings on steel to mitigate biofilm formation. | in marine environments and water systems, it is easy for many structures to form biofilms on their surfaces and to be deteriorated due to the corrosion caused by biofilm formation by bacteria. the authors have investigated the antibacterial effects of metallic elements in practical steels so far to solve food-related problems, using escherichia coli and staphylococcus aureus. however, from the viewpoint of material deterioration caused by bacteria and their antifouling measures, we should consid ... | 2009 | 19333421 |
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 ... | 2009 | 19349747 |
[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 ... | 2009 | 19353881 |
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 ... | 2009 | 19370064 |
the haloprotease cpi produced by the moderately halophilic bacterium pseudoalteromonas ruthenica is secreted by the type ii secretion pathway. | the gene (cpo) encoding the extracellular protease cpi produced by the moderately halophilic bacterium pseudoalteromonas ruthenica cp76 was cloned, and its nucleotide sequence was analyzed. the cpo gene encodes a 733-residue protein showing sequence similarity to metalloproteases of the m4 family. the type ii secretion apparatus was shown to be responsible for secretion of the haloprotease cpi. | 2009 | 19376897 |
differential cold-adaptation among protein components of the thioredoxin system in the psychrophilic eubacterium pseudoalteromonas haloplanktis tac 125. | thioredoxin and thioredoxin reductase from the psychrophilic eubacterium pseudoalteromonas haloplanktis were obtained as recombinant his-tagged proteins (rphtrx and rphtrxr, respectively). rphtrxr is organised as a homodimeric flavoenzyme, whereas rphtrx is a small monomeric protein, both containing a functional disulfide bridge. however, three additional cysteines are present as free thiols in purified rphtrxr. when individually tested in specific assays, rphtrxr and rphtrx display a full activ ... | 2009 | 19381366 |
structure and dynamics of cold-adapted enzymes as investigated by ft-ir spectroscopy and md. the case of an esterase from pseudoalteromonas haloplanktis. | psychrophiles are cold-adapted organisms that produce enzymes that display a high catalytic efficiency at low temperatures. in recent years, these low-temperature working enzymes have attracted the attention of scientists because of their peculiar properties that render them particularly useful in investigating the relationship between enzyme stability and flexibility. recently, a new esterase was identified and isolated from the cold-adapted organism pseudoalteromonas haloplanktis. the enzyme, ... | 2009 | 19435327 |
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 ... | 2009 | 19440232 |
[phylogenetic diversity of cultivable bacteria associated with a sea anemone from coast of the naozhou island in zhanjiang, china]. | to understand the diversity of cultivable bacteria isolated from a sea anemone collected from the coastal water of the naozbou island in the leizhou bay on south china sea. | 2009 | 19445182 |
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 ... | 2009 | 19458654 |
enzymatic degradation of κ-carrageenan in aqueous solution. | enzymatic degradation of standard κ-carrageenan and the low-gelling hybrid κ-/μ-carrageenan were conducted using recombinant pseudoalteromonas carrageenovora κ-carrageenase. the initial velocity of the enzyme was determined as a function of varying tris or nai concentrations and at constant 200 mm cosolutes concentration, adjusting nai and tris concentrations accordingly. in both cases, we observed strong inhibition of the enzyme with increasing amounts of iodide. the characterization of the κ- ... | 2009 | 19459672 |
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 ... | 2009 | 19465132 |
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 ... | 2010 | 19484308 |
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 ... | 2009 | 19504047 |
cold-adapted esterases and lipases: from fundamentals to application. | micro-organisms that thrive at low temperatures produce cold-adapted enzymes which display high catalytic efficiency, generally associated with low thermal stability. in the recent past, researchers and industries have focused the attention on cold-adapted enzymes, whose peculiar properties make them particularly interesting either for investigating stability/flexibility relationships, or for their potential application in industrial processes. among these enzymes, lipases and esterases, have po ... | 2009 | 19508185 |
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 ... | 2009 | 19529929 |
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 ... | 2009 | 19543945 |
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- ... | 2009 | 19544039 |
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 ... | 2009 | 19548693 |
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 ... | 2010 | 19582501 |