Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| shewanella fodinae sp. nov., isolated from a coal mine and from a marine lagoon. | strains jc15(t) and jc19 were isolated from samples collected from different locations in india, including a coal mine and a marine lagoon. both strains were gram-stain-negative rods, motile by means of a single polar flagellum, catalase- and oxidase-positive, and hydrolysed casein, produced h(2)s and showed beta-haemolysis. strain jc15(t) grew optimally at ph 6 (range ph 5-8) while strain jc19 grew optimally at ph 7 (range ph 6-9) and both had a growth temperature optimum of 30-37 degrees c (ra ... | 2010 | 19717581 |
| redox transformation and biogeochemical interaction of heavy metals in korean soil using different treatment columns in the presence of shewanella sp. | the redox transformation and biogeochemical interactions of heavy metals in soil was examined using facultative anaerobic bacterium shewanella sp. (hn-41) in batch mode and with small scale columns. a preliminary study was carried out to determine the influence of various glucose concentrations (10, 20 and 30 mm) on the bacterial growth and releasing of heavy metals from soil using a defined medium. the results showed that the heavy metals were released tremendously in the medium supplemented wi ... | 2009 | 19716584 |
| biodegradation of anthraquinone dyes by shewanella sp. ntou1 under anaerobic conditions. | shewanella sp. ntou1 was able to decolorize a range of anthraquinone dyes [reactive blue 4 (rb4), reactive blue 19 (rb19), mordant red 11 (mr11), disperse red 15 (dr15), and disperse blue 3 (db3)] under anaerobic conditions. by supplementing the medium with formate and ferric citrate as the electron donor and acceptor, respectively and cultivating it under the optimum ph (8-9) and temperature (45 degrees c), this strain could decolorize these dyes (1,000 mg/l) at the initial color removal rates ... | 2009 | 19700827 |
| the effect of flavin electron shuttles in microbial fuel cells current production. | the effect of electron shuttles on electron transfer to microbial fuel cell (mfc) anodes was studied in systems where direct contact with the anode was precluded. mfcs were inoculated with shewanella cells, and flavins used as the electron shuttling compound. in mfcs with no added electron shuttles, flavin concentrations monitored in the mfcs' bulk liquid increased continuously with fmn as the predominant flavin. the maximum concentrations were 0.6 microm for flavin mononucleotide and 0.2 microm ... | 2010 | 19697021 |
| shewanella xiamenensis sp. nov., isolated from coastal sea sediment. | a gram-negative, motile, rod-shaped bacterium, strain s4(t), was isolated from coastal sediment collected off xiamen, china. the physiological and biochemical features of strain s4(t), determined using the api 20ne, api zym and biolog gn2 systems, were similar to those of members of the genus shewanella. phylogenetic analyses based on 16s rrna and gyrb gene sequences placed strain s4(t) in the genus shewanella, and it was most closely related to shewanella oneidensis and related species. dna-dna ... | 2010 | 19684319 |
| microbial reduction of intragrain u(vi) in contaminated sediment. | the accessibility of precipitated, intragrain u(vi) in a contaminated sediment to microbial reduction was investigated to ascertain geochemical and microscopic transport phenomena controlling u(vi) bioavailability. the sediment was collected from the u.s. department of energy hanford site, and contained uranyl precipitates within the mm-sized granitic lithic fragments in the sediment. bioreduction was investigated in a culture of a dissimilatory metal-reducing bacterium, shewanellea oneidensis s ... | 2009 | 19673287 |
| microfabricated microbial fuel cell arrays reveal electrochemically active microbes. | microbial fuel cells (mfcs) are remarkable "green energy" devices that exploit microbes to generate electricity from organic compounds. mfc devices currently being used and studied do not generate sufficient power to support widespread and cost-effective applications. hence, research has focused on strategies to enhance the power output of the mfc devices, including exploring more electrochemically active microbes to expand the few already known electricigen families. however, most of the mfc de ... | 2009 | 19668333 |
| electrochemical measurement of electron transfer kinetics by shewanella oneidensis mr-1. | shewanella oneidensis strain mr-1 can respire using carbon electrodes and metal oxyhydroxides as electron acceptors, requiring mechanisms for transferring electrons from the cell interior to surfaces located beyond the cell. although purified outer membrane cytochromes will reduce both electrodes and metals, s. oneidensis also secretes flavins, which accelerate electron transfer to metals and electrodes. we developed techniques for detecting direct electron transfer by intact cells, using turnov ... | 2009 | 19661057 |
| shewanella chilikensis sp. nov., a moderately alkaliphilic gammaproteobacterium isolated from a lagoon. | a gram-negative, motile, rod-shaped, facultatively anaerobic bacterium was isolated from sediment of chilika lagoon, a brackish water lagoon in india. the strain, designated jc5(t), was able to grow in the presence of 0-8.0 % nacl and at ph 7.0-10.0. the isolate was positive for oxidase and catalase and exhibited alpha-haemolysis. the major fatty acids were iso-c(15 : 0) (18.3 %), c(16 : 0) (11.3 %), c(17 : 1)omega8c (13.1 %) and a summed feature, c(16 : 1)omega7c and/or c(16 : 1)omega6c (15.1 % ... | 2009 | 19643885 |
| invariability of central metabolic flux distribution in shewanella oneidensis mr-1 under environmental or genetic perturbations. | an environmentally important bacterium with versatile respiration, shewanella oneidensis mr-1, displayed significantly different growth rates under three culture conditions: minimal medium (doubling time approximately 3 h), salt stressed minimal medium (doubling time approximately 6 h), and minimal medium with amino acid supplementation (doubling time approximately 1.5 h). (13)c-based metabolic flux analysis indicated that fluxes of central metabolic reactions remained relatively constant under ... | 2009 | 19610125 |
| intermittent energy harvesting improves the performance of microbial fuel cells. | in this study, we compare the efficiencies of harvesting energy from microbial fuel cells (mfc) using two modes of operation: (1) continuous-passing the current through an electrical load-and (2) intermittent-first accumulating the energy in a capacitor and then discharging it through the load. each of these two modes of operation has advantages and disadvantages: the first mode of operation allows the continuous powering of low-power-consuming devices, and the second mode of operation allows th ... | 2009 | 19603683 |
| exafs and hrtem evidence for as(iii)-containing surface precipitates on nanocrystalline magnetite: implications for as sequestration. | arsenic sorption onto iron oxide spinels such as magnetite could contribute to immobilization of arsenite (aso3(3-)), the reduced, highly toxic form of arsenic in contaminated anoxic groundwaters, as well as to putative remediation processes. nanocrystalline magnetite (<20 nm) is known to exhibit higher efficiency for arsenite sorption than larger particles, sorbing as much as approximately 20 micromol/m2 of arsenite. to improve our understanding of this process, we investigated the molecular le ... | 2009 | 19601563 |
| impedance spectroscopy as a tool for non-intrusive detection of extracellular mediators in microbial fuel cells. | endogenously produced, diffusible redox mediators can act as electron shuttles for bacterial respiration. accordingly, the mediators also serve a critical role in microbial fuel cells (mfcs), as they assist extracellular electron transfer from the bacteria to the anode serving as the intermediate electron sink. electrochemical impedance spectroscopy (eis) may be a valuable tool for evaluating the role of mediators in an operating mfc. eis offers distinct advantages over some conventional analyti ... | 2009 | 19585525 |
| the role of 4-hydroxyphenylpyruvate dioxygenase in enhancement of solid-phase electron transfer by shewanella oneidensis mr-1. | we hypothesized that shewanella oneidensis mr-1, a model dissimilatory metal-reducing bacterium, could utilize environmentally relevant concentrations of tyrosine to produce pyomelanin for enhanced fe(iii) oxide reduction. because homogentisate is an intermediate of the tyrosine degradation pathway, and a precursor of a redox-cycling metabolite, pyomelanin, we evaluated the process of homogentisate production by s. oneidensis mr-1, in order to identify the key steps involved in pyomelanin produc ... | 2009 | 19573203 |
| shewanella marina sp. nov., isolated from seawater. | a motile, rod-shaped, pale-brown-pigmented bacterium, designated strain c4t, was isolated from seawater collected from the south sea (republic of korea). cells were gram-negative, facultatively anaerobic, and catalase- and oxidase-positive. the major fatty acids were summed feature 3 (c16:1omega7c and/or iso-c15:0 2-oh; 19.4%), c16:0 (16.3%), c17:1omega8c (9.5%) and iso-c15:0 (7.7%). the dna g+c content was 40.8 mol%. a phylogenetic tree based on 16s rrna gene sequences showed that strain c4t fo ... | 2009 | 19567571 |
| remediation of trichloroethylene by bio-precipitated and encapsulated palladium nanoparticles in a fixed bed reactor. | trichloroethylene is a toxic and recalcitrant groundwater pollutant. palladium nanoparticles bio-precipitated on shewanella oneidensis were encapsulated in polyurethane, polyacrylamide, alginate, silica or coated on zeolites. the reactivity of these bio-pd beads and zeolites was tested in batch experiments and trichloroethylene dechlorination followed first order reaction kinetics. the calculated k-values of the encapsulated catalysts were a factor of six lower compared to non-encapsulated bio-p ... | 2009 | 19560796 |
| engineering of monomeric fk506-binding protein 22 with peptidyl prolyl cis-trans isomerase. importance of a v-shaped dimeric structure for binding to protein substrate. | fk506-binding protein 22 (fkbp22) from the psychrotrophic bacterium shewanella sp. sib1 is a homodimeric protein with peptidyl prolyl cis-trans isomerase (ppiase) (ec 5.2.1.8) activity. each monomer consists of 205 amino acid residues. according to a tertiary model, sib1 fkbp22 assumes a v-shaped structure, in which two monomers interact with each other at their n-termini. each monomer consists of an n-terminal domain with a dimerization core and a c-terminal catalytic domain, which are separate ... | 2009 | 19558490 |
| unexpected chemoreceptors mediate energy taxis towards electron acceptors in shewanella oneidensis. | shewanella oneidensis uses a wide range of terminal electron acceptors for respiration. in this study, we show that the chemotactic response of s. oneidensis to anaerobic electron acceptors requires functional electron transport systems. deletion of the genes encoding dimethyl sulphoxide and trimethylamine n-oxide reductases, or inactivation of these molybdoenzymes as well as nitrate reductase by addition of tungstate, abolished electron acceptor taxis. moreover, addition of nigericin prevented ... | 2009 | 19555457 |
| evaluation of a high-intensity focused ultrasound-immobilized trypsin digestion and 18o-labeling method for quantitative proteomics. | a new method that uses immobilized trypsin concomitant with ultrasonic irradiation results in ultrarapid digestion and more thorough (18)o labeling for quantitative protein comparisons. the method was reproducible and provided effective digestions within <1 min with lower amounts of enzyme, compared to traditional methods. this method was demonstrated for digestion of both simple and complex protein mixtures, including bovine serum albumin, a global proteome extract from the bacteria shewanella ... | 2009 | 19555078 |
| on-line digestion system for protein characterization and proteome analysis. | an efficient on-line digestion system that reduces the number of sample manipulation steps has been demonstrated for high-throughput proteomics. by incorporating a pressurized sample loop into a liquid chromatography-based separation system, both sample and enzyme (e.g., trypsin) can be simultaneously introduced to produce a complete, yet rapid digestion. both standard proteins and a complex shewanella oneidensis global protein extract were digested and analyzed using the automated online pressu ... | 2008 | 19551971 |
| kinetic characterization of omca and mtrc, terminal reductases involved in respiratory electron transfer for dissimilatory iron reduction in shewanella oneidensis mr-1. | we have used scaling kinetics and the concept of kinetic competence to elucidate the role of hemeproteins omca and mtrc in iron reduction by shewanella oneidensis mr-1. second-order rate constants for omca and mtrc were determined by single-turnover experiments. for soluble iron species, a stopped-flow apparatus was used, and for the less reactive iron oxide goethite, a conventional spectrophotometer was used to measure rates. steady-state experiments were performed to obtain molecular rate cons ... | 2009 | 19542342 |
| anaerobic respiration of elemental sulfur and thiosulfate by shewanella oneidensis mr-1 requires psra, a homolog of the phsa gene of salmonella enterica serovar typhimurium lt2. | shewanella oneidensis mr-1, a facultatively anaerobic gammaproteobacterium, respires a variety of anaerobic terminal electron acceptors, including the inorganic sulfur compounds sulfite (so3(2-)), thiosulfate (s2o3(2-)), tetrathionate (s4o6(2-)), and elemental sulfur (s(0)). the molecular mechanism of anaerobic respiration of inorganic sulfur compounds by s. oneidensis, however, is poorly understood. in the present study, we identified a three-gene cluster in the s. oneidensis genome whose trans ... | 2009 | 19542325 |
| limitations and benefits of arisa intra-genomic diversity fingerprinting. | monitoring diversity changes and contamination in mixed cultures and simple microcosms is challenged by fast community structure dynamics, and the need for means allowing fast, cost-efficient and accurate identification of microorganisms at high phylogenetic resolution. the method we explored is a variant of automated rrna intergenic spacer analysis based on intra-genomic diversity fingerprinting (arisa-igdf), and identifies phylotypes with multiple 16s-23s rrna gene intergenic transcribed space ... | 2009 | 19538993 |
| combined effect of an oxygen absorber and oregano essential oil on shelf life extension of rainbow trout fillets stored at 4 degrees c. | in the present study the combined effect of an o2 absorber and oregano essential oil (0.4% v/w) on shelf life extension of rainbow trout fillets (onchorynchus mykiss) stored under refrigeration (4 degrees c) was investigated. the study was based on microbiological [tvc, pseudomonas spp., lactic acid bacteria, h2s-producing bacteria including shewanella putrefaciens, enterobacteriaceae and clostridium spp.), physicochemical (ph, pv, tba, tvbn and drip loss) and sensory (odor, taste) changes occur ... | 2009 | 19527835 |
| effects of oxytetracycline and sulfachloropyridazine residues on the reductive activity of shewanella decolorationis s12. | effects of oxytetracycline (otc) and sulfachloropyridazine (scp), two of the widely used antibiotics in livestock production, on beneficial environmental microorganisms were studied. shewanella decolorationis s12 was selected as the target bacteria for the role in reduction of fe(iii) and dye under anaerobic conditions. the results showed that the antibiotics significantly inhibited fe(iii) reduction and dye decoloration in the reduction system. the rates of fe(ii) formed (-r) were 3.6 and 0.2 m ... | 2009 | 19527026 |
| the agglutination protein agga from shewanella oneidensis mr-1 is a tolc-like protein and forms active channels in vitro. | type i secretion systems (tiss) are associated with the virulence of gram-negative bacteria and the secretion of pathogenic molecular determinants. the shewanella oneidensis mr-1 outer-membrane protein agga is part of a tiss. recombinant agga expressed in escherichia coli as inclusion bodies can be efficiently refolded in vitro, and can form active channel-tunnels as shown by proteoliposome swelling assays and electrophysiological measurements in lipid bilayers. structure-based sequence alignmen ... | 2009 | 19524550 |
| a novel packaging method with a dissolving co(2) headspace combined with organic acids prolongs the shelf life of fresh salmon. | the aim of this study was to evaluate a novel packaging method for fresh fish and to determine its effect on the bacterial growth in fresh salmon. fresh salmon was packed with a small amount of 100% co(2) (gas/product ratio 0.2/1.0 v/v) and a brine solution containing various combinations of citric acid (3% w/w, ph 5), acetic acid (1% w/w, ph 5) and cinnamaldehyde (200 microg/ml). total bacterial counts, counts of sulphur reducing bacteria, lactic acid bacteria and enterobacteriaceae as well as ... | 2009 | 19523706 |
| turnover of quorum sensing signal molecules modulates cross-kingdom signalling. | n-acylhomoserine lactone (ahl) quorum-sensing molecules modulate the swimming behaviour of zoospores of the macroalga ulva to facilitate the location of bacterial biofilms. here we show that the intertidal surfaces colonized by ulva are dominated by alphaproteobacteria, particularly the rhodobacteraceae family, and the bacteroidetes family flavobacteriaceae, and that this diverse assemblage both produces and degrades ahls. n-acylhomoserine lactones could also be extracted from the surfaces of pe ... | 2009 | 19508552 |
| motx and moty are required for flagellar rotation in shewanella oneidensis mr-1. | the single polar flagellum of shewanella oneidensis mr-1 is powered by two different stator complexes, the sodium-dependent pomab and the proton-driven motab. in addition, shewanella harbors two genes with homology to motx and moty of vibrio species. in vibrio, the products of these genes are crucial for sodium-dependent flagellar rotation. resequencing of s. oneidensis mr-1 moty revealed that the gene does not harbor an authentic frameshift as was originally reported. mutational analysis demons ... | 2009 | 19502394 |
| membrane-electrode assembly enhances performance of a microbial fuel cell type biological oxygen demand sensor. | a membrane-electrode assembly (mea) was applied to a microbial fuel cell (mfc) type biological oxygen demand (bod) sensor and the performance of the sensor was assessed. to establish the optimal conditions for mea fabrication, platinum-catalysed carbon cloth cathodic electrodes were assembled with cation exchange membranes under various temperatures and pressures. by analysing coulombs from the mfcs, it could be determined that the optimal hot-pressing conditions were 120 degrees c and 150 kg cm ... | 2009 | 19492544 |
| effect of 2,4-dinitrotoluene on the anaerobic bacterial community in marine sediment. | to study the impact of added 2,4-dinitrotoluene (dnt) on the anaerobic bacterial community in marine sediment collected from an unexploded ordnance dumping site in halifax harbour. | 2009 | 19486208 |
| copper uptake by pseudomonas aeruginosa isolated from infected burn patients. | pseudomonas aeruginosa was isolated from infected burn patients and characterized by standard biochemical tests. the in vitro copper uptake was compared between this isolated pathogenic strain and two non-pathogenic control strains of gram positive bacteria bacillus thuringiensis strain israelis as well as gram negative bacteria enterobacter aerogenes. maximum copper uptake of 470 ppm/g biomass was obtained by p. aeruginosa strain, while the control strains b. thuringiensis and enterobacter aero ... | 2009 | 19484296 |
| antibiotic resistance of gram negatives isolates from loggerhead sea turtles (caretta caretta) in the central mediterranean sea. | previous studies on fish and marine mammals support the hypothesis that marine species harbor antibiotic resistance and therefore may serve as reservoirs for antibiotic-resistance genetic determinants. the aim of this study was to assess the resistance to antimicrobial agents of gram negative strains isolated from loggerhead sea turtles (carettacaretta). oral and cloacal swabs from 19 live-stranded loggerhead sea turtles, with hooks fixed into the gut, were analyzed. the antimicrobial resistance ... | 2009 | 19473669 |
| anti-microfouling activity of lipidic metabolites from the invasive brown alga sargassum muticum (yendo) fensholt. | the purification of the chloroform extract from the brown invasive macroalga sargassum muticum, through a series of chromatographic separations, yielded 12 fractions that were tested against strains of bacteria, microalgae, and fungi involved in marine biofilm formation. the chemical composition of four (a, c, g, and k) out of the six fractions that exhibited anti-microfouling activity was investigated. fraction a contained saturated and unsaturated linear hydrocarbons (c12-c27). arachidonic aci ... | 2010 | 19468792 |
| pfab products determine the molecular species produced in bacterial polyunsaturated fatty acid biosynthesis. | when pdha4, a vector carrying all five pfaa-pfae genes responsible for docosahexaenoic acid (dha; 22:6) biosynthesis in moritella marina mp-1, was coexpressed in escherichia coli with the individual pfaa-pfad genes for eicosapentaenoic acid (epa; 20:5) biosynthesis from shewanella pneumatophori scrc-2738, both polyunsaturated fatty acids were synthesized only in the recombinant carrying pfab for epa synthesis. escherichia coli coexpressing a deleted construct comprising pfaa, pfac, pfad and pfae ... | 2009 | 19453514 |
| using genomic data to determine the diversity and distribution of target site motifs recognized by class c-attc group ii introns. | the attc sites are well-known integrase-targeted elements involved in the insertion and excision of gene cassettes from integrons. recently, functional analysis of sma.i2, a class c-attc group ii intron, showed that this mobile element invades the attc sites through a specific process. the analysis of genomic data indicates that class c-attc group ii introns are independently acquired by their bacterial hosts and evolve in the recognition of a variety of target sites, including the attcs. in add ... | 2009 | 19449055 |
| [influence of amino acid and dipeptide composition on protein stability of piezophilic microbes]. | to compare the amino acid and dipeptide composition of proteins from piezophilic and non-piezophilic microbes is of great significance for understanding the stability of piezophilic protein and directed mutation of them. | 2009 | 19445175 |
| involvement of a membrane-bound class iii adenylate cyclase in regulation of anaerobic respiration in shewanella oneidensis mr-1. | unlike other bacteria that use fnr to regulate anaerobic respiration, shewanella oneidensis mr-1 uses the cyclic amp receptor protein (crp) for this purpose. three putative genes, cyaa, cyab, and cyac, predicted to encode class i, class iv, and class iii adenylate cyclases, respectively, have been identified in the genome sequence of this bacterium. functional validation through complementation of an escherichia coli cya mutant confirmed that these genes encode proteins with adenylate cyclase ac ... | 2009 | 19395492 |
| reduction of nitrate in shewanella oneidensis depends on atypical nap and nrf systems with napb as a preferred electron transport protein from cyma to napa. | in the genome of shewanella oneidensis, a napdaghb gene cluster encoding periplasmic nitrate reductase (napa) and accessory proteins and an nrfa gene encoding periplasmic nitrite reductase (nrfa) have been identified. these two systems seem to be atypical because the genome lacks genes encoding cytoplasmic membrane electron transport proteins, napc for nap and nrfbcd/nrfh for nrf, respectively. here, we present evidence that reduction of nitrate to ammonium in s. oneidensis is carried out by the ... | 2009 | 19387485 |
| c-terminal sequence analysis of 2de-separated proteins. | the overall study of post-translational modifications (ptms) of proteins is gaining strong interest. beside phosphorylation and glycosylation, truncations of the nascent polypeptide chain at the n- or c-terminus are by far the most common types of ptms. nevertheless, little attention has been paid to the development of approaches that allow a systematic analysis of these proteolytic processing events. here we present a protocol that allows the identification of the c-terminal sequence of protein ... | 2009 | 19381603 |
| plutonium(v/vi) reduction by the metal-reducing bacteria geobacter metallireducens gs-15 and shewanella oneidensis mr-1. | we examined the ability of the metal-reducing bacteria geobacter metallireducens gs-15 and shewanella oneidensis mr-1 to reduce pu(vi) and pu(v). cell suspensions of both bacteria reduced oxidized pu [a mixture of pu(vi) and pu(v)] to pu(iv). the rate of plutonium reduction was similar to the rate of u(vi) reduction obtained under similar conditions for each bacteria. the rates of pu(vi) and u(vi) reduction by cell suspensions of s. oneidensis were slightly higher than the rates observed with g. ... | 2009 | 19363069 |
| tandem acyl carrier protein domains in polyunsaturated fatty acid synthases. | polyunsaturated fatty acids (pufas) can be biosynthesized via aerobic pathways that rely on combinations of desaturases and elongases to convert saturated fatty acids to pufas or anaerobic pathways that exploit polyketide synthase (pks)-like enzymes known as pufa synthases for de novo synthesis from acyl coa precursors. in contrast to most fatty acid synthases (fass) and pkss that contain a single acyl carrier protein (acp) domain for each cycle of fatty acid or polyketide chain elongation, all ... | 2009 | 19362636 |
| mitigation of the effect of catholyte contamination in microbial fuel cells using a wicking air cathode. | cathode design greatly affects microbial fuel cell (mfc) performance. cathode contamination is inevitable in a single-chamber mfc yet it is impossible to study the magnitude of this effect in the single-chambered format. therefore to study the effect of contamination at the cathode two-chamber mfcs must be used. the advantages of the two-chamber mfc design used in this study include: the assembled and filled fuel cell is autoclavable and the cathode can easily be moved from the submerged to air ... | 2009 | 19359159 |
| discovering cis-regulatory rnas in shewanella genomes by support vector machines. | an increasing number of cis-regulatory rna elements have been found to regulate gene expression post-transcriptionally in various biological processes in bacterial systems. effective computational tools for large-scale identification of novel regulatory rnas are strongly desired to facilitate our exploration of gene regulation mechanisms and regulatory networks. we present a new computational program named rssvm (rna sampler+support vector machine), which employs support vector machines (svms) f ... | 2009 | 19343219 |
| characterization of a cryptic plasmid psfkw33 from shewanella sp. 33b. | a cryptic plasmid psfkw33 from psychrotrophic bacterium shewanella sp. 33b, an isolate from the gulf of gdansk (the baltic sea), was sequenced and characterized. it is an 8021bp circular molecule with 38% gc content, which shows a distinctive nucleotide sequence without homology to other known plasmids. the nucleotide sequence analysis predicts eight open reading frames. the deduced amino acid sequence of orf-1 shared significant similarity with the phage integrase protein from pseudomonas putid ... | 2009 | 19336243 |
| integron mobilization unit as a source of mobility of antibiotic resistance genes. | antibiotic resistance genes are spread mostly through plasmids, integrons (as a form of gene cassettes), and transposons in gram-negative bacteria. we describe here a novel genetic structure, named the integron mobilization unit (imu), that has characteristics similar to those of miniature inverted transposable elements (mites). two imus (288 bp each) were identified from a carbapenem-resistant enterobacter cloacae isolate that formed a composite structure encompassing a defective class 1 integr ... | 2009 | 19332679 |
| skin and soft tissue infections (patera foot) in immigrants, spain. | an unusual skin and soft tissue infection of the lower limbs has been observed in immigrants from sub-saharan africa who cross the atlantic ocean crowded on small fishing boats (pateras). response to conventional treatment is usually poor. extreme extrinsic factors (including new pathogens) may contribute to the etiology of the infection and its pathogenesis. | 2009 | 19331742 |
| snapshot of iron response in shewanella oneidensis by gene network reconstruction. | iron homeostasis of shewanella oneidensis, a gamma-proteobacterium possessing high iron content, is regulated by a global transcription factor fur. however, knowledge is incomplete about other biological pathways that respond to changes in iron concentration, as well as details of the responses. in this work, we integrate physiological, transcriptomics and genetic approaches to delineate the iron response of s. oneidensis. | 2009 | 19321007 |
| bacterial loads and microbial composition in high pressure treated oysters during storage. | analysis of bacterial communities present in high-pressure (hp)-treated, quick-frozen (qf), and raw oysters was carried out during three different seasons. bacterial numbers and species diversity in each sample were determined at 0, 7, 14, and 21 days of storage. results showed that numbers of total aerobic bacterial counts (tabc) in treated oysters were significantly lower than in untreated oysters at day 0 by 10 to 10(5) colony forming units per gram of oyster meat (cfu/g) in all samplings. ho ... | 2009 | 19303653 |
| 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 |
| antibody recognition force microscopy shows that outer membrane cytochromes omca and mtrc are expressed on the exterior surface of shewanella oneidensis mr-1. | antibody recognition force microscopy showed that omca and mtrc are expressed on the exterior surface of living shewanella oneidensis mr-1 cells when fe(iii), including solid-phase hematite (fe(2)o(3)), was the terminal electron acceptor. omca was localized to the interface between the cell and mineral. mtrc displayed a more uniform distribution across the cell surface. both cytochromes were associated with an extracellular polymeric substance. | 2009 | 19286784 |
| respiratory arsenate reductase as a bidirectional enzyme. | the haloalkaliphilic bacterium alkalilimnicola ehrlichii is capable of anaerobic chemolithoautotrophic growth by coupling the oxidation of arsenite (as(iii)) to the reduction of nitrate and carbon dioxide. analysis of its complete genome indicates that it lacks a conventional arsenite oxidase (aox), but instead possesses two operons that each encode a putative respiratory arsenate reductase (arr). here we show that one homolog is expressed under chemolithoautotrophic conditions and exhibits both ... | 2009 | 19285953 |
| isolation and characterization of shewanella oneidensis wl-7 capable of decolorizing azo dye reactive black 5. | 2009 | 19282633 | |
| [non necrotizing bacterial cellulitis and bacteriemia due to shewanella putrefaciens]. | shewanella putrefaciens is a gram negative opportunistic pathogen which causes skin and soft tissue infections and bacteriemia in immunocompromized patients. we report a 86-year-old man, who presented with an infectious cellulitis of the leg associated with shewanella putrefaciens bacteriemia. this patient was treated by mycophenolate mofetil for a bullous pemphigoid resistant to corticotherapy. | 2009 | 19282070 |
| detection of bacterioplankton in immersed cadavers using selective agar plates. | we measured bacterioplankton in blood from cadavers retrieved from the sea (n=12), near estuaries (n=4), rivers (fresh water, n=8) and from bathtubs (n=4) as well as from non-drowned victims (n=10) discovered near aquatic environments. blood from 11 victims drowned in seawater developed bioluminescent and/or blue colonies (oxidase test positive) on selective media containing 2-4% nacl. homology analyses of the 16s rrna gene showed that all of them were marine bacteria (genera: photobacterium, vi ... | 2009 | 19261520 |
| a putative azoreductase gene is involved in the shewanella oneidensis response to heavy metal stress. | the shewanella oneidensis mr-1 gene so3585, which is annotated as a putative flavin mononucleotide-dependent azoreductase, shares 28% sequence identity with bacillus subtilis azoreductase and pseudomonas putida chrr, a soluble flavoprotein exhibiting chromate reductase activity. reverse transcription polymerase chain reaction demonstrated that the so3585 gene is co-transcribed with two downstream open reading frames: so3586 (a glyoxalase family protein) and so3587 (a predicted membrane-associate ... | 2009 | 19238379 |
| microbial colonization of an in situ sediment cap and correlation to stratified redox zones. | in situ capping is a management technique for contaminated sediments involving the placement of clean material at the sediment-water interface. this work combined porewater geochemical profiling with quantitative microbial data to investigate the intrinsic microbial colonization of a sand cap. geochemical characterization using voltammetric microelectrodes indicated vertical stratification of biogeochemical processes within a capped sediment column. following dissection of the column, quantitati ... | 2009 | 19209586 |
| role and regulation of fatty acid biosynthesis in the response of shewanella piezotolerans wp3 to different temperatures and pressures. | members of the genus shewanella inhabit various environments; they are capable of synthesizing various types of low-melting-point fatty acids, including monounsaturated fatty acids (mufa) and branched-chain fatty acids (bcfa) with and without eicosapentanoic acid (epa). the genes involved in fatty acid synthesis in 15 whole-genome-sequenced shewanella strains were identified and compared. a typical type ii fatty acid synthesis pathway in shewanella was constructed. a complete epa synthesis gene ... | 2009 | 19201790 |
| preliminary characterization and biological reduction of putative biogenic iron oxides (bios) from the tonga-kermadec arc, southwest pacific ocean. | sediment samples were obtained from areas of diffuse hydrothermal venting along the seabed in the tonga sector of the tonga-kermadec arc, southwest pacific ocean. sediments from volcano 1 and volcano 19 were analyzed by x-ray diffraction (xrd) and found to be composed primarily of the iron oxyhydroxide mineral, two-line ferrihydrite. xrd also suggested the possible presence of minor amounts of more ordered iron (hydr)oxides (including six-line ferrihydrite, goethite/lepidocrocite and magnetite) ... | 2009 | 19200145 |
| degeneration of biogenic superparamagnetic magnetite. | magnetite crystals precipitated as a consequence of fe(iii) reduction by shewanella algae bry after 265 h incubation and 5-year anaerobic storage were investigated with transmission electron microscopy, mössbauer spectroscopy and x-ray diffraction. the magnetite crystals were typically superparamagnetic with an approximate size of 13 nm. the lattice constants of the 265 h and 5-year crystals are 8.4164a and 8.3774a, respectively. the mössbauer spectra indicated that the 265 h magnetite had exces ... | 2009 | 19200144 |
| microbial production of ultrafine-grained magnetite by fermentation processes at room temperature. | a method of producing magnetite nanoparticles was developed through culturing a microorganism designated haejae-1, shewanella sp., in the presence of glucose and akaganeite (beta-feooh). haejae-1 isolated from inter-tidal flat sediments was able to produce copious amount of ultrafine magnetite via glucose fermentation extracellularly under anaerobic conditions at room temperature, allowing for easy production, separation, and recovery of the magnetite. tem observation revealed aggregates of smal ... | 2008 | 19198424 |
| [taxonomic characteristics and physiological properties of microorganisms from the gut of pike (esox lucius)]. | the taxonomic composition and distribution of microorganisms differing in the degree of association with the intestinal mucosa of the pike (lucius lucius) has been studied. microorgansism of the families enterobacteriaceae, aeromonadaceae, and vibrionaceae dominate in the gut microflora. numerically prevailing bacterial species are characterized by high proteolytic and amylolytic enzyme activities as well as by high persistence accounted for by antilysozyme and antihistone activities. the result ... | 2008 | 19198074 |
| genomic reconstruction of shewanella oneidensis mr-1 metabolism reveals a previously uncharacterized machinery for lactate utilization. | the ability to use lactate as a sole source of carbon and energy is one of the key metabolic signatures of shewanellae, a diverse group of dissimilatory metal-reducing bacteria commonly found in aquatic and sedimentary environments. nonetheless, homology searches failed to recognize orthologs of previously described bacterial d- or l-lactate oxidizing enzymes (escherichia coli genes dld and lldd) in any of the 13 analyzed genomes of shewanella spp. by using comparative genomic techniques, we ide ... | 2009 | 19196979 |
| shewanella vesiculosa sp. nov., a psychrotolerant bacterium isolated from an antarctic coastal area. | two strains of psychrotolerant bacteria, designated m7(t) and m5, isolated from antarctic coastal marine environments were studied to determine their taxonomic position. the organisms comprised gram-negative, rod-shaped, facultatively anaerobic cells that were motile by means of single polar flagella. neither of the bacterial isolates had a requirement for na(+). these two psychrotolerant strains grew at temperatures ranging from -4 to 30 degrees c. both strains were capable of producing h(2)s f ... | 2009 | 19196774 |
| energy generation coupled to azoreduction by membranous vesicles from shewanella decolorationis s12. | previous studies have demonstrated that shewanella decolorationis s12 can grow on the azo compound amaranth as the sole electron acceptor. thus, to explore the mechanism of energy generation in this metabolism, membranous vesicles (mvs) were prepared and the mechanism of energy generation investigated. the membrane, which was fragmentized during preparation, automatically formed vesicles ranging from 37.5-112.5 nm in diameter under electron micrograph observation. energy was conserved when coupl ... | 2009 | 19190406 |
| simultaneous analysis of physiological and electrical output changes in an operating microbial fuel cell with shewanella oneidensis. | changes in metabolism and cellular physiology of facultative anaerobes during oxygen exposure can be substantial, but little is known about how these changes connect with electrical current output from an operating microbial fuel cell (mfc). a high-throughput voltage based screening assay (vbsa) was used to correlate current output from a mfc containing shewanella oneidensis mr-1 to carbon source (glucose or lactate) utilization, culture conditions, and biofilm coverage over 250 h. lactate induc ... | 2009 | 19189395 |
| mercury stable isotope fractionation during reduction of hg(ii) by different microbial pathways. | mercury (hg) stable isotope fractionation has recently been developed as a tool in biogeochemistry. in this study, the extent of hg stable isotope fractionation during reduction of ionic mercury [hg(ii)] by two hg(ii)-resistant strains, bacillus cereus 5 and the thermophile anoxybacillus sp. fb9 [which actively detoxify hg(ii) by the mer system] and a hg(ii)-sensitive metal-reducing anaerobe, shewanella oneidensis mr-1 [which reduces hg(ii) at low concentrations], was investigated. in all cases, ... | 2008 | 19174888 |
| [acute dermohypodermitis of the right leg (s. putrefaciens) after sea bathing]. | 2009 | 19171235 | |
| two different stator systems drive a single polar flagellum in shewanella oneidensis mr-1. | the gram-negative metal ion-reducing bacterium shewanella oneidensis mr-1 is motile by means of a single polar flagellum. we identified two potential stator systems, pomab and motab, each individually sufficient as a force generator to drive flagellar rotation. physiological studies indicate that pomab is sodium-dependent while motab is powered by the proton motive force. flagellar function mainly depends on the pomab stator; however, the presence of both stator systems under low-sodium conditio ... | 2009 | 19170881 |
| early detection of oxidized surfaces using shewanella oneidensis mr-1 as a tool. | corrosion is a natural global problem of immense importance. oxidation of iron and steel not only compromises the structural stability of a widely used and versatile material but it also creates an abrasive compound (iron oxide) that can score the surfaces of metals, rendering them useless for the purpose for which they were designed. clearly, the identification of corrosion in its nascent stages is a high priority for reasons that range from aesthetics to economics. many bacteria in the faculta ... | 2009 | 19165644 |
| exploration of csp genes from temperate and glacier soils of the indian himalayas and in silico analysis of encoding proteins. | the metagenomic csp library was constructed from the temperate and glacier soils of central himalaya, india followed by polymerase chain reaction (pcr) amplification. the library was further screened for low-temperature adaptation, and the positive recombinants were sorted out by determining changes in the melting temperature (tm). a homology search of cloned sequence showed their identity with the csp genes of pseudomonas fluorescens, psychrobacter cryohalolentis k5, and shewanella spp mr-4. am ... | 2009 | 19159976 |
| electronic absorption spectra and redox properties of c type cytochromes in living microbes. | shewanella is an electrogenic microbe that has significant content of c type cytochromes (ca. 0.5 mm). this feature allows the optical absorption spectra of the cell-membrane-associated proteins to be monitored in vivo in the course of extracellular respiratory electron-transfer reactions. the results show significant differences to those obtained in vitro with purified proteins. | 2009 | 19156795 |
| diversity of beta-propeller phytase genes in the intestinal contents of grass carp provides insight into the release of major phosphorus from phytate in nature. | phytate is the most abundant organic phosphorus compound in nature, and microbial mineralization of phytate by phytase is a key process for phosphorus recycling in the biosphere. in the present study, beta-propeller phytase (bpp) gene fragments were readily amplified from the intestinal contents of grass carp (ctenopharyngodon idellus) directly or from phytate-degrading isolates from the same source, confirming the widespread occurrence of bpp in aquatic communities. the amounts of sequences col ... | 2009 | 19151187 |
| analysis by mutagenesis of a chromosomal integron integrase from shewanella amazonensis sb2bt. | integrons are mobile genetic elements that can integrate and disseminate genes as cassettes by a site-specific recombination mechanism. integrons contain an integrase gene (inti) that carries out recombination by interacting with two different target sites; the atti site in cis with the integrase and the palindromic attc site of a cassette. the plasmid-specified inti1 excises a greater variety of cassettes (principally antibiotic resistance genes), and has greater activity, than chromosomal inte ... | 2009 | 19136589 |
| identification of psychrophile shewanella sp. kmg427 as an eicosapentaenoic acid producer. | an isolate from holothurians was identified as an eicosapentaenoic acid (epa)-producing bacterium kmg427, which is characterized by epa synthesis efficiency, by thin layer and gas chromatographic analyses. the epa production was maximized to more than 10% of the total fatty acids by incubation at 4o degrees c after cell proliferation at 20 degrees c. the isolated bacterium was categorized as gramnegative, rod-shaped, aerobic, and motile with a single polar flagellum. according to phylogenetic an ... | 2008 | 19131686 |
| identification and characterization of two alternative sigma factors of rna polymerase in the deep-sea piezophilic bacterium shewanella violacea, strain dss12. | two genes for alternative sigma factors, sigma(e2) and sigma(e3), classified in the extracytoplasmic function sigma family for rna polymerases, were identified in the deep-sea piezophilic bacterium shewanella violacea dss12. amino acid alignments revealed that the domains for transcriptional functions were comparatively conserved compared with escherichia coli sigma(e) in both proteins. core-binding analysis suggested that both proteins function as sigma factors. | 2009 | 19129643 |
| crystal structure of the fic (filamentation induced by camp) family protein so4266 (gi|24375750) from shewanella oneidensis mr-1 at 1.6 a resolution. | 2009 | 19127588 | |
| involvement of shewanella oneidensis mr-1 luxs in biofilm development and sulfur metabolism. | the role of luxs in shewanella oneidensis mr-1 has been examined by transcriptomic profiling, biochemical, and physiological experiments. the results indicate that a mutation in luxs alters biofilm development, not by altering quorum-sensing abilities but by disrupting the activated methyl cycle (amc). the s. oneidensis wild type can produce a luminescence response in the ai-2 reporter strain vibrio harveyi mm32. this luminescence response is abolished upon the deletion of luxs. the deletion of ... | 2009 | 19124589 |
| destabilization of psychrotrophic rnase hi in a localized fashion as revealed by mutational and x-ray crystallographic analyses. | the arg97 --> gly and asp136 --> his mutations stabilized so-rnase hi from the psychrotrophic bacterium shewanella oneidensis mr-1 by 5.4 and 9.7 degrees c, respectively, in t(m), and 3.5 and 6.1 kj x mol(-1), respectively, in deltag(h2o). these mutations also stabilized the so-rnase hi derivative (4x-rnase hi) with quadruple thermostabilizing mutations in an additive manner. as a result, the resultant sextuple mutant protein (6x-rnase hi) was more stable than the wild-type protein by 28.8 degre ... | 2009 | 19120449 |
| comparative temporal proteomics of a response regulator (so2426)-deficient strain and wild-type shewanella oneidensis mr-1 during chromate transformation. | predicted orphan response regulators encoded in the shewanella oneidensis mr-1 genome are poorly understood from a cellular function perspective. our previous transcriptomic and proteomic analyses demonstrated that an annotated dna-binding response regulator, so2426, was significantly up-regulated in wild-type s. oneidensis cells at both the mrna and protein levels in response to acute chromate [cr(vi)] challenge, suggesting a potential regulatory role for this protein in metal stress pathways. ... | 2009 | 19118451 |
| in vivo assembly and single-molecule characterization of the transcription machinery from shewanella oneidensis mr-1. | harnessing the new bioremediation and biotechnology applications offered by the dissimilatory metal-reducing bacteria, shewanella oneidensis mr-1, requires a clear understanding of its transcription machinery, a pivotal component in maintaining vitality and in responding to various conditions, including starvation and environmental stress. here, we have reconstituted the s. oneidensis rna polymerase (rnap) core in vivo by generating a co-overexpression construct that produces a long polycistroni ... | 2009 | 19111618 |
| tuning of functional heme reduction potentials in shewanella fumarate reductases. | the fumarate reductases from s. frigidimarina ncimb400 and s. oneidensis mr-1 are soluble and monomeric enzymes located in the periplasm of these bacteria. these proteins display two redox active domains, one containing four c-type hemes and another containing fad at the catalytic site. this arrangement of single-electron redox co-factors leading to multiple-electron active sites is widespread in respiratory enzymes. to investigate the properties that allow a chain of single-electron co-factors ... | 2009 | 19081388 |
| self-constructed electrically conductive bacterial networks. | 2009 | 19072958 | |
| experimental approach for deep proteome measurements from small-scale microbial biomass samples. | many methods of microbial proteome characterizations require large quantities of cellular biomass (>1-2 g) for sample preparation and protein identification. our experimental approach differs from traditional techniques by providing the ability to identify the proteomic state of a microbe from a few milligrams of starting cellular material. the small-scale, guanidine lysis method minimizes sample loss by achieving cellular lysis and protein digestion in a single-tube experiment. for this experim ... | 2008 | 19072265 |
| reductive processes controlling arsenic retention: revealing the relative importance of iron and arsenic reduction. | the fate and transport of arsenic is regulated, in part, by its strong affinity for iron (hydr)oxides. a transition from aerobic to anaerobic conditions resulting in concomitant reduction of both as(v) and iron (hydr)oxides can thus have a pronounced influence on as partitioning. however, it is presently unclear whether as desorption under anaerobic conditions results predominantly from a transformation from as(v) to as(iii) or from mineralogical changes as a consequence of iron and manganese re ... | 2008 | 19068807 |
| functional roles of arca, etra, cyclic amp (camp)-camp receptor protein, and cya in the arsenate respiration pathway in shewanella sp. strain ana-3. | microbial arsenate respiration can enhance arsenic release from arsenic-bearing minerals--a process that can cause arsenic contamination of water. in shewanella sp. strain ana-3, the arsenate respiration genes (arrab) are induced under anaerobic conditions with arsenate and arsenite. here we report how genes that encode anaerobic regulator (arca and etra [fnr homolog]) and carbon catabolite repression (crp and cya) proteins affect arsenate respiration in ana-3. transcription of arca, etra, and c ... | 2009 | 19060154 |
| catabolite repression control of napf (periplasmic nitrate reductase) operon expression in escherichia coli k-12. | escherichia coli, a facultative aerobe, expresses two distinct respiratory nitrate reductases. the periplasmic napabc enzyme likely functions during growth in nitrate-limited environments, whereas the membrane-bound narghi enzyme functions during growth in nitrate-rich environments. maximal expression of the napfdaghbc operon encoding periplasmic nitrate reductase results from synergistic transcription activation by the fnr and phospho-narp proteins, acting in response to anaerobiosis and nitrat ... | 2009 | 19060147 |
| the tetraheme cytochrome from shewanella oneidensis mr-1 shows thermodynamic bias for functional specificity of the hemes. | bacteria of the genus shewanella contain an abundant small tetraheme cytochrome in their periplasm when growing anaerobically. data collected for the protein isolated from s. oneidensis mr-1 and s. frigidimarina indicate differences in the order of oxidation of the hemes. a detailed thermodynamic characterization of the cytochrome from s. oneidensis mr-1 in the physiological ph range was performed, with data collected in the ph range 5.5-9.0 from nmr experiments using partially oxidized samples ... | 2009 | 19048308 |
| microbial iron redox cycling in a circumneutral-ph groundwater seep. | the potential for microbially mediated redox cycling of iron (fe) in a circumneutral-ph groundwater seep in north central alabama was studied. incubation of freshly collected seep material under anoxic conditions with acetate-lactate or h(2) as an electron donor revealed the potential for rapid fe(iii) oxide reduction (ca. 700 to 2,000 micromol liter(-1) day(-1)). fe(iii) reduction at lower but significant rates took place in unamended controls (ca. 300 micromol liter(-1) day(-1)). culture-based ... | 2009 | 19047399 |
| investigation of the structure and function of a shewanella oneidensis arsenical-resistance family transporter. | the toxic metalloid arsenic is an abundant element and most organisms possess transport systems involved in its detoxification. one such family of arsenite transporters, the acr3 family, is widespread in fungi and bacteria. to gain a better understanding of the molecular mechanism of arsenic transport, we report here the expression and characterization of a family member, so_acr3, from the bacterium shewanella oneidensis mr-1. surprisingly, expression of this transporter in the arsenic-hypersens ... | 2008 | 19039703 |
| structure of biogenic uraninite produced by shewanella oneidensis strain mr-1. | the stability of biogenic uraninite with respect to oxidation is seminal to the success of in situ bioreduction strategies for remediation of subsurface u(vi) contamination. the properties and hence stability of uraninite are dependent on its size, structure, and composition. in this study, the local-, intermediate-, and long-range molecular-scale structure of nanoscale uraninite produced by shewanella oneidensis strain mr-1 was investigated using exafs, sr-based powder diffraction and tem. the ... | 2008 | 19031878 |
| metabolic flux analysis of shewanella spp. reveals evolutionary robustness in central carbon metabolism. | shewanella spp. are a group of facultative anaerobic bacteria widely distributed in marine and freshwater environments. in this study, we profiled the central metabolic fluxes of eight recently sequenced shewanella species grown under the same condition in minimal medium with [3-13c] lactate. although the tested shewanella species had slightly different growth rates (0.23-0.29 h(-1)) and produced different amounts of acetate and pyruvate during early exponential growth (pseudo-steady state), the ... | 2009 | 19031428 |
| protein evolution in deep sea bacteria: an analysis of amino acids substitution rates. | abyssal microorganisms have evolved particular features that enable them to grow in their extreme habitat. genes belonging to specific functional categories are known to be particularly susceptible to high-pressure; therefore, they should show some evidence of positive selection. to verify this hypothesis we computed the amino acid substitution rates between two deep-sea microorganisms, photobacterium profundum ss9 and shewanella benthica kt99, and their respective shallow water relatives. | 2008 | 19014525 |
| eicosapentaenoic acid plays a beneficial role in membrane organization and cell division of a cold-adapted bacterium, shewanella livingstonensis ac10. | shewanella livingstonensis ac10, a psychrotrophic gram-negative bacterium isolated from antarctic seawater, produces eicosapentaenoic acid (epa) as a component of phospholipids at low temperatures. epa constitutes about 5% of the total fatty acids of cells grown at 4 degrees c. we found that five genes, termed orf2, orf5, orf6, orf7, and orf8, are specifically required for the synthesis of epa by targeted disruption of the respective genes. the mutants lacking epa showed significant growth retar ... | 2009 | 19011019 |
| a structural basis for the regulatory inactivation of dnaa. | regulatory inactivation of dnaa is dependent on hda (homologous to dnaa), a protein homologous to the aaa+ (atpases associated with diverse cellular activities) atpase region of the replication initiator dnaa. when bound to the sliding clamp loaded onto duplex dna, hda can stimulate the transformation of active dnaa-atp into inactive dnaa-adp. the crystal structure of hda from shewanella amazonensis sb2b at 1.75 a resolution reveals that hda resembles typical aaa+ atpases. the arrangement of the ... | 2009 | 19000695 |
| high-throughput protein concentration and buffer exchange: comparison of ultrafiltration and ammonium sulfate precipitation. | high-throughput protein purification is a complex, multi-step process. there are several technical challenges in the course of this process that are not experienced when purifying a single protein. among the most challenging are the high-throughput protein concentration and buffer exchange, which are not only labor-intensive but can also result in significant losses of purified proteins. we describe two methods of high-throughput protein concentration and buffer exchange: one using ammonium sulf ... | 2009 | 18988034 |
| scaling up microbial fuel cells. | the goal of this study was to quantify the relation between the surface area of the current-limiting electrode of a microbial fuel cell (mfc) and the power density generated by the mfc. shewanella oneidensis (mr-1) was grown anaerobically in the anodic compartment of an mfc utilizing lactate as the electron donor. graphite plate electrodes of various sizes were used as anodes. commercially available air electrodes, composed of manganese-based catalyzed carbon bonded to a current-collecting scree ... | 2008 | 18983087 |
| studies of iron-uptake mechanisms in two bacterial species of the shewanella genus adapted to middle-range (shewanella putrefaciens) or antarctic (shewanella gelidimarina) temperatures. | iron(iii)-uptake mechanisms in bacteria indigenous to the antarctic, which is the most fe-deficient continent on earth, have not been extensively studied. the cold-adapted, antarctic bacterium, shewanella gelidimarina, does not produce detectable levels of the siderophore, putrebactin, in the supernatant of fe(iii)-deprived cultures. this is distinct from the putrebactin-producing bacterium from the same genus, shewanella putrefaciens, which is adapted to middle-range temperatures. the productio ... | 2008 | 18972501 |
| the solution structure of a tetraheme cytochrome from shewanella frigidimarina reveals a novel family structural motif. | the bacteria belonging to the genus shewanella are facultative anaerobes that utilize a variety of terminal electron acceptors which includes soluble and insoluble metal oxides. the tetraheme c-type cytochrome isolated during anaerobic growth of shewanella frigidimarina ncimb400 ( sfc) contains 86 residues and is involved in the fe(iii) reduction pathways. although the functional properties of sfc redox centers are quite well described, no structures are available for this protein. in this work, ... | 2008 | 18950243 |
| biocatalytic dechlorination of trichloroethylene with bio-palladium in a pilot-scale membrane reactor. | trichloroethylene (tce) is a toxic and recalcitrant groundwater pollutant. an innovative technology using microbial produced pd(0) nanoparticles for the remediation of tce contaminated groundwater was developed. the nanoscale bio-pd particles were precipitated on the biomass of shewanella oneidensis and hydrogen gas, formate, or formic acid were used as hydrogen donors. ethane turned out to be the only organic degradation product and no intermediate chlorinated reaction products were detected. s ... | 2009 | 18949748 |