| biosynthesis of antibiotic prodiginines in the marine bacterium hahella chejuensis kctc 2396. | hahella chejuensis kctc 2396 produces red pigments, showing antibacterial and algicidal activities. the main red-coloured metabolite of the pigments was identified as antibiotic prodigiosin. with the expectation that the red pigments are a mixture of a series of close relatives, the aim of the present study is to detect new antibiotic prodigiosin analogues and to analyse the biosynthetic pattern for prodiginines in kctc 2396. | 2007 | 17381736 |
| biochemical characterization of atud from pseudomonas aeruginosa, the first member of a new subgroup of acyl-coa dehydrogenases with specificity for citronellyl-coa. | the aturabcdefgh gene cluster is essential for acyclic terpene utilization (atu) in pseudomonas aeruginosa. the biochemical functions of most atu proteins have not been experimentally verified; exceptions are atuc/atuf, which constitute the two subunits of geranyl-coa carboxylase, the key enzyme of the atu pathway. in this study we investigated the biochemical function of atud and of the pa1535 gene product, a protein related to atud in amino acid sequence. 2d gel electrophoresis showed that atu ... | 2008 | 18310025 |
| hahella antarctica sp. nov., isolated from antarctic seawater. | a gram-negative, psychrotolerant, chemoheterotrophic, aerobic, cream-coloured bacterium, designated imcc3113(t), was isolated from coastal seawater from the antarctic. on the basis of 16s rrna gene sequence similarity analyses, the strain was most closely related to the type strains of hahella chejuensis (93.0 %) and hahella ganghwensis (92.1 %) in the gammaproteobacteria. phylogenetic investigations using 16s rrna gene sequences showed that this antarctic marine isolate formed a robust monophyl ... | 2008 | 18218930 |
| prodigiosin isolated from hahella chejuensis suppresses lipopolysaccharide-induced no production by inhibiting p38 mapk, jnk and nf-kappab activation in murine peritoneal macrophages. | prodigiosin was isolated from marine bacteria hahella chejuensis which has been recently discovered from marado, cheju island, republic of korea. immunosuppressive properties have been reported for prodigiosin members such as undecylprodigiosin, metacycloprodigiosin, prodigiosin and its synthetic analogue pnu156804 (pnu). however, the effect of this agent on macrophage function has not been characterized in detail. in the present study, we examined the effects of prodigiosin on the production of ... | 2007 | 17996695 |
| structural insight of the role of the hahella chejuensis hapk protein in prodigiosin biosynthesis. | | 2008 | 17729271 |
| stability of microbial communities in goat milk during a lactation year: molecular approaches. | the microbial communities in milks from one herd were evaluated during 1-year of lactation, using molecular methods to evaluate their stability and the effect of breeding conditions on their composition. the diversity of microbial communities was measured using two approaches: molecular identification by 16s and 18s rdna sequencing of isolates from counting media (two milks), and direct identification using 16s rdna from clone libraries (six milks). the stability of these communities was evaluat ... | 2007 | 17604934 |
| genomic blueprint of hahella chejuensis, a marine microbe producing an algicidal agent. | harmful algal blooms, caused by rapid growth and accumulation of certain microalgae in the ocean, pose considerable impacts on marine environments, aquatic industries and even public health. here, we present the 7.2-megabase genome of the marine bacterium hahella chejuensis including genes responsible for the biosynthesis of a pigment which has the lytic activity against a red-tide dinoflagellate. h.chejuensis is the first sequenced species in the oceanospiralles clade, and sequence analysis rev ... | 2005 | 16352867 |
| characterization of bacterium isolated from the sediment at coastal area of omura bay in japan and several biological activities of pigment produced by this isolate. | recently we discovered a bacterial strain (ms-02-063) that produces large amounts of red pigment from coastal area of nagasaki prefecture, japan. comparative 16s rdna gene sequencing analysis revealed that strain ms-02-063 was phylogenetically closely related to gamma-proteobacterium hahella sp. mbic 3957 that produces prodigiosin. however, some physiological and biochemical differences between strain ms-02-063 and hahella sp. mbic 3957 were observed. the red pigment (rp-063) produced by this is ... | 2005 | 15905602 |
| hahella ganghwensis sp. nov., isolated from tidal flat sediment. | a marine bacterial strain, designated fr1050(t), was isolated from a sediment sample of getbol (korean tidal flat). phylogenetic investigations based on 16s rrna gene sequence analysis showed that the isolate formed a robust monophyletic clade with hahella chejuensis within the gamma-proteobacteria. sequence similarity between strain fr1050(t) and the type strain of hahella chejuensis was 94.7 %. cells were gram-negative, aerobic, rod-shaped, motile and halophilic; optimum growth occurred at sea ... | 2005 | 15774643 |
| zooshikella ganghwensis gen. nov., sp. nov., isolated from tidal flat sediments. | two red pigment-producing bacterial strains with a metallic green sheen were isolated from a sediment sample of getbol, the korean tidal flat. phylogenetic analysis based on 16s rdna sequences showed that these isolates represent a phyletic lineage within the gamma-proteobacteria that is distantly related to the genus hahella. no bacterial species with validly published names showed > or = 92% 16s rrna similarity with the getbol isolates. the strains were gram-negative, chemo-organotrophic, aero ... | 2003 | 12892120 |
| a simple method for dna extraction from marine bacteria that produce extracellular materials. | we present a simple method for extracting dna from the marine bacteria hahella chejuensis, a streptomyces sp., and a cytophaga sp. previously, dna purification from these strains was hindered by the presence of extracellular materials. in our extraction method, the marine bacteria are lysed by freezing and grinding in liquid nitrogen, and treated with sds. the extracted dna is purified using a phenol/chloroform mixture, and precipitated in isopropanol. the extracted dna is of high quality and su ... | 2003 | 12459245 |
| hahella chejuensis gen. nov., sp. nov., an extracellular-polysaccharide-producing marine bacterium. | a bacterial strain, designated 96cj10356t, which produced abundant extracellular polysaccharides and red pigment was isolated from marine sediment collected from marado, cheju island, republic of korea. the organism is gram-negative, aerobic, rod-shaped and motile. growth was not observed in the absence of nacl, and was optimal at an nacl concentration of 2%. the strain contained oxidase and catalase, and was able to hydrolyse aesculin and gelatin. the major cellular fatty acids were saturated o ... | 2001 | 11321112 |
| conformational heterogeneity and dynamics in a βγ-crystallin from hahella chejuensis. | most of the βγ-crystallins are structural proteins with high intrinsic stability, which gets enhanced by ca(2+)-binding in microbial members. functions of most of these proteins are yet to be known. however, a few of them were reported to be involved in ca(2+)-dependent and stress-related functions. hahellin, a microbial homolog, is a natively unfolded protein that acquires a well-folded structure upon ca(2+) binding. although the structure of βγ-crystallin domains is well understood, the dynami ... | 2011 | 21549498 |
| β-propeller phytase hydrolyzes insoluble ca(2+)-phytate salts and completely abrogates the ability of phytate to chelate metal ions. | phytate is an antinutritional factor that influences the bioavailability of essential minerals by forming complexes with them and converting them into insoluble salts. to further our understanding of the chemistry of phytate's binding interactions with biologically important metal cations, we determined the stoichiometry, affinity, and thermodynamics of these interactions by isothermal titration calorimetry. the results suggest that phytate has multiple ca(2+)-binding sites and forms insoluble t ... | 2010 | 20964370 |
| a natively unfolded βγ-crystallin domain from hahella chejuensis. | to date, very few βγ-crystallins have been identified and structurally characterized. several of them have been shown to bind ca(2+) and thereby enhance their stability without any significant change in structure. although ca(2+)-induced conformational changes have been reported in two putative βγ-crystallins from caulobacter crescentus and yersinia pestis, they are shown to be partially unstructured, and whether they acquire a βγ-crystallin fold is not known. we describe here a βγ-crystallin do ... | 2010 | 20929244 |
| crystal structure of dihydrodipicolinate synthase from hahella chejuensis at 1.5 a resolution. | lysine biosynthesis has been of interest in plant research, because lysine is the most limiting amino acid in crop protein production. dihydrodipicolinate synthase (dhdps) catalyzes the branch point reaction leading to meso-diaminopimelate (dap) and (s)-lysine in lysine biosynthesis. in this report, we present the crystal structure of dhdps from the marine bacterium hahella chejuensis (hcdhdps) at 1.5 a resolution. the four subunits of the asymmetric unit assemble to form a tetramer with an appr ... | 2010 | 20227435 |
| an expansin-like protein from hahella chejuensis binds cellulose and enhances cellulase activity. | molecular function of the expansin superfamily has been highlighted for cellulosic biomass conversion. in this report, we identified a new bacterial expansin subfamily by analysis of related bacterial sequences and biochemically examined a member of this new subfamily from hahella chejuensis (hcexlx2). among the various complex polysaccharides tested, hcexlx2 bound most efficiently to cellulose. the relative binding constant (k( r )) against avicel was 2.1 l g(-1) at ph 6.0 and 4 degrees c. hcex ... | 2010 | 20213317 |
| genome-wide screening and identification of factors affecting the biosynthesis of prodigiosin by hahella chejuensis, using escherichia coli as a surrogate host. | a marine bacterium, hahella chejuensis, recently has attracted attention due to its lytic activity against a red-tide dinoflagellate. the algicidal function originates from its red pigment, prodigiosin, which also exhibits immunosuppressive or anticancer activity. genome sequencing and functional analysis revealed a gene set contained in the hap gene cluster that is responsible for the biosynthesis of prodigiosin. to screen for the factors affecting the prodigiosin biosynthesis, we constructed a ... | 2010 | 20038694 |
| sequence specific 1h, 13c, and 15n resonance assignments of hahellin from hahella chejuensis, a putative member of the betagamma-crystallin superfamily. | the sequence specific (1)h, (13)c, and (15)n resonance assignments of hahellin, a putative member of betagamma-crystallin family, from hahella chejuensis, have been accomplished by nmr spectroscopy. the resonance assignments reveal that the protein adopts predominantly a beta-sheet conformation as in the case of betagamma-crystallin folds. | 2008 | 19636892 |
| statistical optimization of medium components for the production of prodigiosin by hahella chejuensis kctc 2396. | prodigiosin is a natural red pigment with algicidal activity against cochlodinium polykrikoides, a major harmful redtide microalga. to increase the yield of prodigiosin production by hahella chejuensis kctc 2396, significant medium components were determined using a two-level plackett- burman statistical design technique. among 12 components included in basal medium, nahco3, na2sio3, nh4no3, na2so4, and cacl2 were determined to be important for prodigiosin production. the medium formulation was ... | 2008 | 19131691 |
| red to red - the marine bacterium hahella chejuensis and its product prodigiosin for mitigation of harmful algal blooms. | harmful algal blooms (habs), commonly called red tides, are caused by some toxic phytoplanktons, and have made massive economic losses as well as marine environmental disturbances. as an effective and environment-friendly strategy to control hab outbreaks, biological methods using marine bacteria capable of killing the harmful algae or algicidal extracellular compounds from them have been given attention. a new member of the gamma-proteobacteria, hahella chejuensis kctc 2396, was originally isol ... | 2008 | 18955809 |
| unusual odd-electron fragments from even-electron protonated prodiginine precursors using positive-ion electrospray tandem mass spectrometry. | reports of anticancer and immunosuppressive properties have spurred recent interest in the bacterially produced prodiginines. we use electrospray tandem mass spectrometry (es-ms/ms) to investigate prodigiosin, undecylprodiginine, and streptorubin b (butyl-meta-cycloheptylprodiginine) and to explore their fragmentation pathways to explain the unusual methyl radical loss and consecutive fragment ions that dominate low-energy collision-induced dissociation (cid) mass spectra. the competition betwee ... | 2008 | 18774733 |
| mutant selection of hahella chejuensis kctc 2396 and statistical optimization of medium components for prodigiosin yield-up. | prodigiosin is a natural red pigment with algicidal activity against cochlodinium polykrikoides, a major harmful red-tide microalga. to increase the yield of prodigiosin, a mutant of hahella chejuenesis kctc 2396, assigned m3349, was developed by an antibiotic mutagenesis using chloramphenicol. when cultured in sucrose-based marine broth medium (smb), m3349 could produce prodigiosin at 1.628+/-0.06 g/l, while wild type producing at 0.658+/-0.12 g/l under the same conditions. to increase the yiel ... | 2008 | 18545968 |
| overexpression, on-column refolding and isotopic labeling of hahellin from hahella chejuensis, a putative member of the betagamma-crystallin superfamily. | a gene which encodes a hypothetical protein of 40 kda has been identified in the genome of a marine bacterium hahella chejuensis, as a putative member of betagamma-crystallin superfamily. this hypothetical protein contains a putative betagamma-crystallin-like domain, along with other domains for carbohydrate binding regions. it is named as hahellin. a pcr amplified stretch of 92-amino acid residue long protein was cloned into pet21a vector and overexpressed in escherichia coli strain bl21(de3)pl ... | 2008 | 18267367 |