| predictive models as means to quantify the interactions of spoilage organisms. | the purpose of this paper is to quantify the interactions of some groups of spoilage organisms that can be usually found in refrigerated meat stored in air, such as: enterobacteriaceae, pseudomonas, acinetobacter, psychrobacter, shewanella, carnobacterium, lactobacillus, leuconostoc, brochothrix and kurthia spp. the growth of these organisms was studied in the range of temperature 2-11 degrees c and ph 5.2-6.4, which is characteristic of refrigerated meat. the main growth parameters (maximum spe ... | 1998 | 9631338 |
| sialic acid-binding lectin with antibacterial activity from the horse mussel: further characterization and immunolocalization. | a heterogeneous sialic acid-binding lectin with affinity for bacterial lps was isolated and partially characterized from hemolymph of the horse mussel modiolus modiolus.(1) using two-dimensional electrophoresis with immobilized ph gradients, the lectin revealed three subunits with different molecular weight and isoelectric points (pi); mr14 (pi approximately 5.1 and approximately 5.5), 17.5 (pi approximately 5.5) and 20 (pi approximately 4.9) kda. the affinity purified lectin existed in its nati ... | 1998 | 9639084 |
| design and application of two rapid screening techniques for isolation of mn(iv) reduction-deficient mutants of shewanella putrefaciens. | chemical mutagenesis procedures and two newly developed rapid plate assays were used to identify two mn(iv) reduction-deficient (mnr) mutants of shewanella putrefaciens. all eleven members of a set of previously isolated fe(iii) reduction-deficient (fer) mutants displayed mnr-positive phenotypes on the plate assays and were also capable of anaerobic growth on mn(iv) as the sole terminal electron acceptor. | 1998 | 9647855 |
| purification of a ccb-type quinol oxidase specifically induced in a deep-sea barophilic bacterium, shewanella sp. strain db-172f. | we investigated for the first time the respiratory chain system of a deep-sea barophilic bacterium, shewanella sp. strain db-172f. a membrane-bound ccb-type quinol oxidase, from cells grown at 60 mpa pressure, was purified to an electrophoretically homogeneous state. the purified enzyme complex consisted of four kinds of subunits with molecular masses of 98, 66, 18.5, and 15kda, and it contained 0.96 mol of protoheme and 1.95mol of covalently bound heme c per mol of enzyme. only protoheme in the ... | 1998 | 9672683 |
| sensorial and microbial effects of gaseous ozone on fresh scad (trachurus trachurus). | the bactericidal activity of gaseous ozone was investigated using a commercial ozone generator. five species of fish bacteria, pseudomonas putida, shewanella putrefaciens, brochothrix thermosphacta, enterobacter sp. and lactobacillus plantarum, were inoculated on agar surfaces and exposed to different ozonation times in a gas chamber. results showed ozone in relatively low concentrations (< 0.27 x 10(-3) g l-1) was an effective bactericide of vegetative cells of the five fish bacteria. the age o ... | 1998 | 9674134 |
| isolation of shewanella putrefaciens from a rheumatic heart disease patient with infective endocarditis. | | 1998 | 9675697 |
| the molecular biology of barophilic bacteria. | many microorganisms from the deep-sea display high-pressure-adapted--also described as barophilic or piezophilic--growth characteristics. phylogenetic studies have revealed that a large proportion of the barophilic bacteria currently in culture collections belong to a distinct subgroup of the genus shewanella, referred to as the "barophile branch." many of the basic properties of barophiles that enable their survival at extremes of pressure remain to be elucidated. however, several genes whose e ... | 1997 | 9680316 |
| volatile components associated with bacterial spoilage of tropical prawns. | analysis of headspace volatiles by gas chromatography/mass spectrometry from king (penaeus plebejus), banana (p. merguiensis), tiger (p. esculentus/semisulcatus) and greasy (metapenaeus bennettae) prawns stored in ice or ice slurry, which is effectively an environment of low oxygen tension, indicated the presence of amines at the early stages of storage (less than 8 days) irrespective of the nature of the storage media. esters were more prevalent in prawns stored on ice (normal oxygen conditions ... | 1998 | 9706797 |
| structure of the acidic polysaccharide chain of the lipopolysaccharide of shewanella alga 48055. | a lipopolysaccharide (lps) with an acidic polysaccharide chain was isolated from the bacterium shewanella alga strain 48055 and cleaved selectively at the glycosidic linkage of n-acetylneuraminic acid to give a tetrasaccharide. studies of the tetrasaccharide and the o-deacylated lps by 1h and 13c nmr spectroscopy, including 2d cosy, tocsy, noesy, rotating-frame noe spectroscopy (roesy), and h-detected 1h, 13c heteronuclear multiple-quantum coherence (hmqc) experiments, revealed the following str ... | 1998 | 9720241 |
| isolation and sequence of omca, a gene encoding a decaheme outer membrane cytochrome c of shewanella putrefaciens mr-1, and detection of omca homologs in other strains of s. putrefaciens. | the sequence of the omca gene, which encodes a decaheme cytochrome c that is localized to the outer membrane (om) of shewanella putrefaciens mr-1, was determined. the 2202 bp nucleotide sequence of omca encodes for 734 amino acids with a predicted molecular protein mass of 78.6 kda. comparison with the amino-terminal sequence of the mature protein suggests the presence of a hydrophobic leader sequence which is cleaved during translocation of the protein to the om. this leader sequence has a lipo ... | 1998 | 9733973 |
| shewanella amazonensis sp. nov., a novel metal-reducing facultative anaerobe from amazonian shelf muds. | a new bacterial species belonging to the genus shewanella is described on the basis of phenotypic characterization and sequence analysis of its 16s rrna-encoding and gyrase b (gyrb) genes. this organism, isolated from shallow-water marine sediments derived from the amazon river delta, is a gram-negative, motile, polarly flagellated, facultatively anaerobic, rod-shaped eubacterium and has a g&c content of 51.7 mol%. strain sb2bt is exceptionally active in the anaerobic reduction of iron, manganes ... | 1998 | 9734053 |
| structure and function of flavocytochrome c3, the soluble fumarate reductase from shewanella ncimb400. | | 1998 | 9765890 |
| mechanisms of gene expression controlled by pressure in deep-sea microorganisms. | a pressure-regulated operon has been cloned and sequenced from deep-sea barophilic shewanella strains. to understand pressure-regulated mechanisms of gene expression, a regulatory element upstream of the pressure-regulated operon from shewanella sp. strain dss12 was studied. regions a and b were classified by sequence analysis. a unique octamer motif, aaggtaag, was found to be repeated in tandem 13 times in region b. an electrophoretic mobility shift assay demonstrated that a o54-like factor rec ... | 1998 | 9783159 |
| the role of biomineralization in microbiologically influenced corrosion. | synthetic iron oxides (goethite, alpha-feo.oh; hematite, fe2o3; and ferrihydrite, fe(oh)3) were used as model compounds to simulate the mineralogy of surface films on carbon steel. dissolution of these oxides exposed to pure cultures of the metal-reducing bacterium, shewanella putrefaciens, was followed by direct atomic absorption spectroscopy measurement of ferrous iron coupled with microscopic analyses using confocal laser scanning and environmental scanning electron microscopies. during an 8- ... | 1998 | 9807800 |
| molecular analysis of the trimethylamine n-oxide (tmao) reductase respiratory system from a shewanella species. | trimethylamine n-oxide (tmao) is an abundant compound of tissues of marine fish and invertebrates. during fish spoilage, certain marine bacteria can reduce tmao to nauseous trimethylamine (tma). one such bacterium has been isolated and identified as a new shewanella species, and called shewanella massilia. the anaerobic growth of s. massilia is greatly increased when tmao is added, indicating that tmao reduction involves a respiratory pathway. the tora enzyme responsible for tmao reduction is a ... | 1998 | 9813127 |
| crystal structure of oxidized trimethylamine n-oxide reductase from shewanella massilia at 2.5 a resolution. | the periplasmic trimethylamine n-oxide (tmao) reductase from the marine bacteria shewanella massilia is involved in a respiratory chain, having trimethylamine n-oxide as terminal electron acceptor. this molybdoenzyme belongs to the dimethyl sulfoxide (dmso) reductase family, but has a different substrate specificity than its homologous enzyme. while the dmso reductases reduce a broad spectra of organic s-oxide and n-oxide compounds, tmao reductase from shewanella massilia reduces only tmao as th ... | 1998 | 9813128 |
| taxonomic studies of deep-sea barophilic shewanella strains and description of shewanella violacea sp. nov. | several barophilic shewanella species have been isolated from deep-sea sediments at depths of 2,485-6,499 m. from the results of taxonomic studies, all of these isolates have been identified as strains of shewanella benthica except for strain dss12. strain dss12 is a member of a novel, moderately barophilic shewanella species isolated from the ryukyu trench at a depth of 5,110 m. on marine agar 2216 plates, this organism produced a violet pigment, whereas the colonies of other isolates (s. benth ... | 1998 | 9818352 |
| shewanella putrefaciens mtrb encodes an outer membrane protein required for fe(iii) and mn(iv) reduction. | iron and manganese oxides or oxyhydroxides are abundant transition metals, and in aquatic environments they serve as terminal electron acceptors for a large number of bacterial species. the molecular mechanisms of anaerobic metal reduction, however, are not understood. shewanella putrefaciens is a facultative anaerobe that uses fe(iii) and mn(iv) as terminal electron acceptors during anaerobic respiration. transposon mutagenesis was used to generate mutants of s. putrefaciens, and one such mutan ... | 1998 | 9829939 |
| polyphosphate-accumulating and denitrifying bacteria isolated from anaerobic-anoxic and anaerobic-aerobic sequencing batch reactors | in this study, phosphate-accumulating bacteria achieved complete phosphate removal in two different systems: an anaerobic-anoxic sequencing batch reactor and an anaerobic-aerobic sequencing batch reactor. this result shows that phosphate-accumulating bacteria in the a2 sbr can use nitrate as terminal electron acceptor instead of oxygen. phosphate-accumulating bacteria accumulated phosphate with a rates between 30 and 70 mg p/l/h in the a/o sbr and between 15 and 32 mg p/l/h in the a2 sbr. twenty ... | 1999 | 9841775 |
| changes in the microbial community in japan trench sediment from a depth of 6292 m during cultivation without decompression. | a sample of deep-sea sediment was obtained from the japan trench at a depth of 6292 m using a pressure-retaining sediment sampler. microorganisms in the sediment sample were cultivated in marine broth 2216 at ambient pressure (65 mpa) without decompression, and at atmospheric pressure (0.1 mpa) as a control experiment. 16s ribosomal rna genes (rdna) were amplified by pcr from dna extracted from the original sediment sample and the mixed cultures, and the nucleotide sequences were determined. the ... | 1999 | 9919678 |
| cold-active serine alkaline protease from the psychrotrophic bacterium shewanella strain ac10: gene cloning and enzyme purification and characterization. | the gene encoding serine alkaline protease (sapsh) of the psychrotrophic bacterium shewanella strain ac10 was cloned in escherichia coli. the amino acid sequence deduced from the 2,442-bp nucleotide sequence revealed that the protein was 814 amino acids long and had an estimated molecular weight of 85,113. sapsh exhibited sequence similarities with members of the subtilisin family of proteases, and there was a high level of conservation in the regions around a putative catalytic triad consisting ... | 1999 | 9925590 |
| chemical and sensory changes associated with microbial flora of mediterranean boque (boops boops) stored aerobically at 0, 3, 7, and 10 degreesc. | the development of a microbial population and changes in the physicochemical and sensorial characteristics of mediterranean boque (boops boops), called gopa in greece, stored aerobically at 0, 3, 7, and 10 degreesc were studied. pseudomonads and shewanella putrefaciens were the dominant bacteria at the end of the storage period, regardless of the temperature tested. enterobacteria and brochothrix thermosphacta also grew, but their population density was always 2 to 3 log10 cfu g-1 less than that ... | 1999 | 9925603 |
| phylogeny of marine and freshwater shewanella: reclassification of shewanella putrefaciens ncimb 400 as shewanella frigidimarina. | dissimilatory fe(iii) reduction by shewanella putrefaciens and related species has generated considerable interest in biochemical characterization of the pathways for anaerobic electron transfer in this organism. two strains, mr-1 and ncimb 400, have been extensively used, and several respiratory enzymes have been isolated from each. it has become apparent that significant sequence differences exist between homologous proteins from these strains. the 16s rrna from ncimb 400 was sequenced and com ... | 1999 | 10028262 |
| redox properties of flavocytochrome c3 from shewanella frigidimarina ncimb400. | the thermodynamic and catalytic properties of flavocytochrome c3 from shewanella frigidimarina have been studied using a combination of protein film voltammetry and solution methods. as measured by solution kinetics, maximum catalytic efficiencies for fumarate reduction (kcat/km = 2.1 x 10(7) m-1 s-1 at ph 7.2) and succinate oxidation (kcat/km = 933 m-1 s-1 at ph 8.5) confirm that flavocytochrome c3 is a unidirectional fumarate reductase. very similar catalytic properties are observed for the en ... | 1999 | 10079073 |
| taxonomic studies of extremely barophilic bacteria isolated from the mariana trench and description of moritella yayanosii sp. nov., a new barophilic bacterial isolate. | we have isolated two strains of extremely barophilic bacteria from sediment collected from the world's deepest ocean floor in the mariana trench, challenger deep, at a depth of 10898m [kato c, li l, nogi y, nakamura y, tamaoka j, horikoshi k (1998) appl environ microbiol 64:1510-1513]. one strain, db21mt-2, was identified as a strain of shewanella benthica, and the other strain, db21mt-5, is closely affiliated with members of the genus moritella on the basis of 16s rdna sequence analysis. the hy ... | 1999 | 10086847 |
| enzymatical properties of psychrophilic phosphatase i. | phosphatase i purified from a psychrophile (shewanella sp.) [tsuruta et al. (1998) j. biochem. 123, 219-225] dephosphorylated o-phospho-l-tyrosine and phospho-tyrosyl residues in phosphorylated poly(glu4,tyr1) random polymer (polyey) and phosphorylated myelin basic protein (mbp) but not phosphoseryl and/or phosphothreonyl residues in phosphorylated histone h1, casein and phosphorylase a, indicating that the enzyme showed protein-tyrosine-phosphatase (ptpase, ec 3.1.3.48)-like activity in vitro. ... | 1999 | 10101281 |
| polyphasic taxonomy of the genus shewanella and description of shewanella oneidensis sp. nov. | the genus shewanella has been studied since 1931 with regard to a variety of topics of relevance to both applied and environmental microbiology. recent years have seen the introduction of a large number of new shewanella-like isolates, necessitating a coordinated review of the genus. in this work, the phylogenetic relationships among known shewanellae were examined using a battery of morphological, physiological, molecular and chemotaxonomic characterizations. this polyphasic taxonomy takes into ... | 1999 | 10319494 |
| primary shewanella alga septicemia in a patient on hemodialysis. | we report the first japanese case of primary septicemia with shewanella alga and also describe the bacteriological characteristics of and results of antibiotic susceptibility tests of the isolate. s. alga was repeatedly isolated, at times simultaneously with escherichia coli, from the blood of a 64-year-old female undergoing hemodialysis. the isolated organism was determined to be s. alga based on recently published identification criteria, such as hemolysis on sheep blood agar, no acid producti ... | 1999 | 10325394 |
| crystallization and preliminary x-ray crystallographic analysis of a periplasmic tetrahaem flavocytochrome c3 from shewanella frigidimarina ncimb400 which has fumarate reductase activity. | the fumarate reductase of escherichia coli and other bacteria is a membrane-bound enzyme consisting of four subunits. a soluble periplasmic 64 kda tetrahaem flavocytochrome c3 from shewanella frigidimarina ncimb400 which possesses a catalytic fumarate reductase activity has been crystallized. the crystals belong to space group p212121 with unit-cell parameters a = 72.4, b = 110.1, c = 230.2 a. assuming a molecular dimer in the asymmetric unit, the crystals contain 65% solvent and, when cryocoole ... | 1999 | 10329791 |
| cytochrome c-dependent methacrylate reductase from geobacter sulfurreducens am-1. | geobacter sulfurreducens am-1 can use methacrylate as a terminal electron acceptor for anaerobic respiration. in this paper, we report on the purification and properties of the periplasmic methacrylate reductase, and show that the enzyme is dependent on the presence of a periplasmic cytochrome c (apparent k(m) = 0.12 microm). the methacrylate reductase was found to be composed of only one polypeptide with an apparent molecular mass of 50 kda and to contain, bound tightly but not covalently, 1 mo ... | 1999 | 10406941 |
| characterization of a flavocytochrome that is induced during the anaerobic respiration of fe3+ by shewanella frigidimarina ncimb400. | a 63.9 kda periplasmic tetrahaem flavocytochrome c(3), designated ifc(3), was found to be expressed in shewanella frigidimarina ncimb400 grown anaerobically with ferric citrate or ferric pyrophosphate as the sole terminal electron acceptor, but not in anaerobic cultures of the bacterium with other respiratory substrates. ifc(3) was purified to homogeneity and revealed by biochemical, spectroscopic and primary structure analyses to contain four low-spin bis-his-ligated c(3)-haems, with midpoint r ... | 1999 | 10455032 |
| occurrence of shewanella algae in danish coastal water and effects of water temperature and culture conditions on its survival. | the marine bacterium shewanella algae, which was identified as the cause of human cases of bacteremia and ear infections in denmark in the summers of 1994 and 1995, was detected in seawater only during the months (july, august, september, and october) when the water temperature was above 13 degrees c. the bacterium is a typical mesophilic organism, and model experiments were conducted to elucidate the fate of the organism under cold and nutrient-limited conditions. the culturable count of s. alg ... | 1999 | 10473392 |
| cold-adapted alanine dehydrogenases from two antarctic bacterial strains: gene cloning, protein characterization, and comparison with mesophilic and thermophilic counterparts. | the genes encoding nad(+)-dependent alanine dehydrogenases (aladhs) (ec 1.4.1.1) from the antarctic bacterial organisms shewanella sp. strain ac10 (shealadh) and carnobacterium sp. strain st2 (caraladh) were cloned and expressed in escherichia coli. of all of the aladhs that have been sequenced, shealadh exhibited the highest level of sequence similarity to the aladh from the gram-negative bacterium vibrio proteolyticus (vpraladh). caraladh was most similar to aladhs from mesophilic and thermoph ... | 1999 | 10473410 |
| crystallization and preliminary x-ray analysis of flavocytochrome c(3), the fumarate reductase from shewanella frigidimarina. | the fumarate reductase (flavocytochrome c(3)) from shewanella frigidimarina (formerly s. putrefaciens) ncimb400 has been crystallized in the space group p2(1), with cell dimensions of a = 45.447 a, b = 92.107 a, c = 78.311 a, and beta = 91.038 degrees and one molecule per asymmetric unit. a native data set has been collected to 1.8 a. the gene encoding fcc(3) from the s. frigidimarina type strain acam591 has been cloned and sequenced and the protein crystallized in space group p2(1) with cell di ... | 1999 | 10479620 |
| cloning of two cold shock genes, cspa and cspg, from the deep-sea psychrophilic bacterium shewanella violacea strain dss12. | we cloned and characterized two cold shock inducible genes from the deep-sea psychrophilic bacterium shewanella violacea strain dss12. the cloned genes, designated cspa and cspg, encode proteins each consisting of 70 amino acid residues which show 62 and 67% sequence identity with escherichia coli cspa and cspg, respectively. at-rich up elements were found immediately upstream of the promoter region and the cspa and cspg mrna contained unusually long 5' untranslated regions like that in the e. c ... | 1999 | 10483731 |
| iron isotope biosignatures. | the (56)fe/(54)fe of fe-bearing phases precipitated in sedimentary environments varies by 2.5 per mil (delta(56)fe values of +0.9 to -1. 6 per mil). in contrast, the (56)fe/(54)fe of fe-bearing phases in igneous rocks from earth and the moon does not vary measurably (delta(56)fe = 0.0 +/- 0.3 per mil). experiments with dissimilatory fe-reducing bacteria of the genus shewanella algae grown on a ferrihydrite substrate indicate that the delta(56)fe of ferrous fe in solution is isotopically lighter ... | 1999 | 10489362 |
| [elastase activity of gram-negative non-fermenting bacteria and two variations of a simple method for their detection]. | the ability to produce elastase was examined in 1,168 strains of 11 representative genera of gram-negative non-fermenting bacteria isolated from weakened patients in the course of eight years. detection of the elastase activity was performed parallelly using the conventional method and its pulverisation variant. the difference between the results accomplished by the classical method and its pulverisation variant (53.9% versus 60.5% detected elastase-positive strains) was highly significant (p < ... | 1999 | 10528445 |
| protein-mediated adhesion of the dissimilatory fe(iii)-reducing bacterium shewanella alga bry to hydrous ferric oxide. | the rate and extent of bacterial fe(iii) mineral reduction are governed by molecular-scale interactions between the bacterial cell surface and the mineral surface. these interactions are poorly understood. this study examined the role of surface proteins in the adhesion of shewanella alga bry to hydrous ferric oxide (hfo). enzymatic degradation of cell surface polysaccharides had no effect on cell adhesion to hfo. the proteolytic enzymes streptomyces griseus protease and chymotrypsin inhibited t ... | 1999 | 10543817 |
| shewanella pealeana sp. nov., a member of the microbial community associated with the accessory nidamental gland of the squid loligo pealei. | a new, mesophillic, facultatively anaerobic, psychrotolerant bacterium, strain ang-sq1t (t = type strain), was isolated from a microbial community colonizing the accessory nidamental gland of the squid loligo pealei. it was selected from the community on the basis of its ability to reduce elemental sulfur. the cells are motile, gram-negative rods (2.0-3.0 microns long, 0.4-0.6 micron wide). ang-sq1t grows optimally over the temperature range of 25-30 degrees c and a ph range of 6.5-7.5 degrees c ... | 1999 | 10555311 |
| identification of the syntrophic partners in a coculture coupling anaerobic methanol oxidation to fe(iii) reduction. | from enrichments with methanol and ferric pyrophosphate a coculture was isolated which coupled methanol oxidation to carbon dioxide with the reduction of fe(iii) to fe(ii). 16s rrna gene analysis of the isolated syntrophic partners revealed 99.5% similarity to clostridium sphenoides and 98.5% to shewanella putrefaciens. formation of fe(ii) coupled to methanol oxidation was confirmed by using strains of culture collections (c. sphenoides dsm 632 and s. putrefaciens dsm 9461). the importance of th ... | 1999 | 10556712 |
| open conformation of a flavocytochrome c3 fumarate reductase. | fumarate reductases and succinate dehydrogenases play central roles in the metabolism of eukaryotic and prokaryotic cells. a recent medium resolution structure of the escherichia coli fumarate reductase (frd) has revealed the overall organization of the membrane-bound complex. here we present the first high resolution x-ray crystal structure of a water-soluble bacterial fumarate reductase in an open conformation. this structure reveals a mobile domain that modulates substrate access to the activ ... | 1999 | 10581549 |
| structural and mechanistic mapping of a unique fumarate reductase. | the 1.8 a resolution crystal structure of the tetraheme flavocytochrome c3, fcc3, provides the first mechanistic insight into respiratory fumarate reductases or succinate dehydrogenases. the multi-redox center, three-domain protein shows a 40 a long 'molecular wire' allowing rapid conduction of electrons through a new type of cytochrome domain onto the active site flavin, driving the reduction of fumarate to succinate. in this structure a malate-like molecule is trapped in the enzyme active site ... | 1999 | 10581550 |
| structure and mechanism of the flavocytochrome c fumarate reductase of shewanella putrefaciens mr-1. | fumarate respiration is one of the most widespread types of anaerobic respiration. the soluble fumarate reductase of shewanella putrefaciens mr-1 is a periplasmic tetraheme flavocytochrome c. the crystal structures of the enzyme were solved to 2.9 a for the uncomplexed form and to 2.8 a and 2.5 a for the fumarate and the succinate-bound protein, respectively. the structures reveal a flexible capping domain linked to the fad-binding domain. a catalytic mechanism for fumarate reduction based on th ... | 1999 | 10581551 |
| a study of deep-sea natural microbial populations and barophilic pure cultures using a high-pressure chemostat. | continuous cultures in which a high-pressure chemostat was used were employed to study the growth responses of (i) deep-sea microbial populations with the naturally occurring carbon available in seawater and with limiting concentrations of supplemental organic substrates and (ii) pure cultures of copiotrophic barophilic and barotolerant deep-sea isolates in the presence of limiting carbon concentrations at various pressures, dilution rates, and temperatures. we found that the growth rates of nat ... | 1999 | 10583982 |
| use of time-temperature integrators and predictive modelling for shelf life control of chilled fish under dynamic storage conditions. | a systematic approach for fish shelf life modelling and time temperature integrator (tti) selection in order to plan and apply an effective quality monitoring scheme for the fish chill chain was developed. the temperature behaviour of the natural microflora of the mediterranean fish boque (boops boops) was studied and growth of the specific spoilage bacteria pseudomonas spp. and shewanella putrefaciens was modelled and correlated to organoleptic shelf life. arrhenius and square root functions we ... | 1999 | 10598111 |
| acetone formation in the vibrio family: a new pathway for bacterial leucine catabolism. | there is current interest in biological sources of acetone, a volatile organic compound that impacts atmospheric chemistry. here, we determined that leucine-dependent acetone formation is widespread in the vibrionaceae. sixteen vibrio isolates, two listonella species, and two photobacterium angustum isolates produced acetone in the presence of l-leucine. shewanella isolates produced much less acetone. growth of vibrio splendidus and p. angustum in a fermentor with controlled aeration revealed th ... | 1999 | 10601206 |
| role of the tetraheme cytochrome cyma in anaerobic electron transport in cells of shewanella putrefaciens mr-1 with normal levels of menaquinone. | shewanella putrefaciens mr-1 possesses a complex electron transport system which facilitates its ability to use a diverse array of compounds as terminal electron acceptors for anaerobic respiration. a previous report described a mutant strain (cmtn-1) deficient in cyma, a tetraheme cytochrome c. however, the interpretation of the electron transport role of cyma was complicated by the fact that cmtn-1 was also markedly deficient in menaquinones. this report demonstrates that the depressed menaqui ... | 2000 | 10613864 |
| homogeneity of danish environmental and clinical isolates of shewanella algae. | danish isolates of shewanella algae constituted by whole-cell protein profiling a very homogeneous group, and no clear distinction was seen between strains from the marine environment and strains of clinical origin. although variation between all strains was observed by ribotyping and random amplified polymorphic dna analysis, no clonal relationship between infective strains was found. from several patients, clonally identical strains of s. algae were reisolated up to 8 months after the primary ... | 2000 | 10618264 |
| bacterial reduction of copper-contaminated ferric oxide: copper toxicity and the interaction between fermentative and iron-reducing bacteria. | fe(iii) oxide is an important heavy-metal sink, and bacteria are responsible for much of the fe(iii) reduced in nonsulfidogenic aquatic environments, yet factors governing the bacterial reduction of heavy metal-contaminated iron oxide are largely unknown. in this study with a stabilized bacterial consortium enriched from metal-contaminated sediments, we demonstrate that cu toxicity impedes anaerobic carbon oxidation and bacterial reduction of hydrous ferric oxide (hfo). in the enrichment culture ... | 2000 | 10629273 |
| voltammetry of a flavocytochrome c(3): the lowest potential heme modulates fumarate reduction rates. | iron-induced flavocytochrome c(3), ifc(3), from shewanella frigidimarina ncimb400, derivatized with a 2-pyridyl disulfide label, self-assembles on gold electrodes as a functional array whose fumarate reductase activity as viewed by direct electrochemistry is indistinguishable from that of ifc(3) adsorbed on gold or graphite electrodes. the enhanced stability of the labeled protein's array permits analysis at a rotating electrode and limiting catalytic currents fit well to a michaelis-menten desc ... | 2000 | 10653813 |
| competitive pcr-dgge analysis of bacterial mixtures: an internal standard and an appraisal of template enumeration accuracy. | analysis of polymerase chain reaction (pcr) amplified 16s rdna fragments from environmental samples by denaturing gradients of chemicals or heat [denaturing gradient gel electrophoresis (dgge) and thermal gradient gel electrophoresis (tgge)] within polyacrylamide gels is a popular tool in microbial ecology. difficulties in acceptance of the technique and interpretation of the results remain, due to its qualitative nature. in this study we have addressed this problem by the construction and evalu ... | 2000 | 10699667 |
| dissimilatory fe(iii) oxide reduction by shewanella alga bry requires adhesion. | the derjaguin-landau-verwey-overbeek (dlvo) theory was used to examine the relationship between adhesion and dissimilatory fe(iii) oxide reduction. adhesion of shewanella alga bry to hydrous ferric oxide (hfo) was correlated with ionic strength and thus was accurately described by the dlvo theory. reduction of insoluble hfo was also correlated with kcl concentration. in contrast, there was no correlation between soluble fe(iii) reduction and ionic strength. a correlation between hfo reduction ra ... | 2000 | 10706667 |
| isolation of u(vi) reduction-deficient mutants of shewanella putrefaciens. | a u(vi) reduction-deficient mutant (urr) screening technique was developed and combined with chemical mutagenesis procedures to identify a urr mutant of shewanella putrefaciens strain 200. the urr mutant lacked the ability to grow anaerobically on u(vi) and no(2)(-), yet retained the ability to grow anaerobically on eight other compounds as terminal electron acceptor. all 11 members of previously isolated sets of fe(iii) and mn(iv) reduction-deficient mutants of s. putrefaciens 200 displayed urr ... | 2000 | 10713412 |
| purification and magneto-optical spectroscopic characterization of cytoplasmic membrane and outer membrane multiheme c-type cytochromes from shewanella frigidimarina ncimb400. | two membranous c-type cytochromes from the fe(iii)-respiring bacterium shewanella frigidimarina ncimb400, cyma and omca, have been purified and characterized by uv-visible, magnetic circular dichroism, and electron paramagnetic resonance spectroscopies. the 20-kda cyma is a member of the napc/nirt family of multiheme cytochromes, which are invariably anchored to the cytoplasmic membrane of gram-negative bacteria, and are postulated to mediate electron flow between quinols and periplasmic redox p ... | 2000 | 10722689 |
| cloning of phosphatase i gene from a psychrophile, shewanella sp., and some properties of the recombinant enzyme. | psychrophilic phosphatase i from shewanella sp. is a cold enzyme that was found as a novel protein-tyrosine-phosphatase (ptpase, ec 3. 1.3.48) with a histidine as its catalytic residue [tsuruta and aizono (1999) j. biochem. 125, 690-695]. here, we determined the nucleotide sequence of a dna fragment (2,004 bp) containing the phosphatase i gene by cloning with polymerase chain reaction (pcr) and inverted pcr techniques. the deduced amino acid sequence, of the enzyme contained a conserved region o ... | 2000 | 10731677 |
| chromium(vi) reductase activity is associated with the cytoplasmic membrane of anaerobically grown shewanella putrefaciens mr-1. | shewanella putrefaciens mr-1 can reduce a diverse array of compounds under anaerobic conditions, including manganese and iron oxides, fumarate, nitrate, and many other compounds. these reductive processes are apparently linked to a complex electron transport system. chromium (cr) is a toxic and mutagenic metal and bacteria could potentially be utilized to immobilize cr by reducing the soluble and bioavailable state, cr(vi), to the insoluble and less bioavailable state, cr(iii). formate-dependent ... | 2000 | 10735248 |
| an algorithm for automated bacterial identification using matrix-assisted laser desorption/ionization mass spectrometry. | an algorithm for bacterial identification using matrix-assisted laser desorption/ionization (maldi) mass spectrometry is being developed. this mass spectral fingerprint comparison algorithm is fully automated and statistically based, providing objective analysis of samples to be identified. based on extraction of reference fingerprint ions from test spectra, this approach should lend itself well to real-world applications where samples are likely to be impure. this algorithm is illustrated using ... | 2000 | 10740862 |
| cloning and characterization of the gene encoding rna polymerase sigma factor sigma(54) of deep-sea piezophilic shewanella violacea. | we have recently reported that a sigma(54)-like factor recognizes a dna element, designated as region a, upstream of a pressure-regulated operon in piezophilic shewanella violacea strain dss12 (nakasone et al., fems microbiology lett. 176 (1999) 351-356). in this study, we isolated and characterized the rpon gene of this piezophilic bacterium. the rpon gene was found to encode a putative protein consisting of 492 amino acid residues with a predicted molecular mass of 55359 da. significant homolo ... | 2000 | 10760597 |
| expression of the transcripts of the sigma factors and putative sigma factor regulators of chlamydia trachomatis l2. | the steady state levels of the transcripts of the beta' subunit of rna polymerase gene (rpoc), three sigma factor genes (rpod, rpon, and rpsd), and four putative sigma factor regulatory genes (rsbw, rsbv1, rsbv2, and rsbu) of chlamydia trachomatis l2 were examined during the chlamydial developmental cycle by reverse transcription-polymerase chain reaction (rt-pcr) analysis. rpoc and the major sigma factor rpod transcripts were detected at all times post-infection, consistent with their expected ... | 2000 | 10773461 |
| pressure regulation of soluble cytochromes c in a deep-sea piezophilic bacterium, shewanella violacea. | two c-type cytochromes from the soluble fraction of a deep-sea moderately piezophilic bacterium, shewanella violacea, were purified and characterized, and the genes coding for these cytochromes were cloned and sequenced. one of the cytochromes, designated cytochrome c(a), was found to have a molecular mass of approximately 8.3 kda, and it contained one heme c per molecule. the other, designated cytochrome c(b), was found to have a molecular mass of approximately 23 kda, and it contained two heme ... | 2000 | 10781566 |
| bacteriology of infected cavitating lung tumor. | differentiation between in situ infection and simple tumor necrosis in cavitating lung tumors by means of imaging studies is difficult. in this study, we prospectively investigated the role of ultrasound (us)-guided transthoracic aspiration for bacteriologic examination of infected cavitating lung tumors, and the influence of the culture results on the treatment of patients. twenty-two patients (18 men and four women) with cavitating lung tumors treated from january 1996 to october 1998 were inc ... | 2000 | 10806182 |
| a role for excreted quinones in extracellular electron transfer. | respiratory processes in bacteria are remarkable because of their ability to use a variety of compounds, including insoluble minerals, as terminal electron acceptors. although much is known about microbial electron transport to soluble electron acceptors, little is understood about electron transport to insoluble compounds such as ferric oxides. in anaerobic environments, humic substances can serve as electron acceptors and also as electron shuttles to ferric oxides. to explore this process, we ... | 2000 | 10811225 |
| crystal structures of an oxygen-binding cytochrome c from rhodobacter sphaeroides. | the photosynthetic bacterium rhodobacter sphaeroides produces a heme protein (shp), which is an unusual c-type cytochrome capable of transiently binding oxygen during autooxidation. similar proteins have not only been observed in other photosynthetic bacteria but also in the obligate methylotroph methylophilus methylotrophus and the metal reducing bacterium shewanella putrefaciens. a three-dimensional structure of shp was derived using the multiple isomorphous replacement phasing method. besides ... | 2000 | 10821858 |
| reclassification of alteromonas distincta romanenko et al. 1995 as pseudoalteromonas distincta comb. nov. | the 16s rrna gene of alteromonas distincta kmm 638t was amplified, cloned and sequenced. the nucleotide sequence was aligned with sequences of representative strains of alteromonas, moritella, pseudoalteromonas and shewanella. results of phylogenetic analysis, using neighbour-joining and fitch-margoliash methods, clearly indicated that this species should be assigned to the genus pseudoalteromonas. on the basis of polyphasic data obtained from previous work and this study, it is proposed that th ... | 2000 | 10826797 |
| structural analysis of the ntrbc genes of deep-sea piezophilic shewanella violacea. | the ntrbc genes coding for the bacterial signal-transducing protein ntrb and the bacterial enhancer-binding protein ntrc of deep-sea piezophilic shewanella violacea were cloned and their nucleotide sequences were analyzed. the conserved regions of ntrb and those of ntrc are well conserved in the case of the ntrbc products of s. violacea. | 2000 | 10830521 |
| effect of temperature and salinity stress on growth and lipid composition of shewanella gelidimarina. | the maximum growth temperature, the optimal growth temperature, and the estimated normal physiological range for growth of shewanella gelidimarina are functions of water activity (a(w)), which can be manipulated by changing the concentration of sodium chloride. the growth temperatures at the boundaries of the normal physiological range for growth were characterized by increased variability in fatty acid composition. under hyper- and hypoosmotic stress conditions at an a(w) of 0.993 (1.0% [wt/vol ... | 2000 | 10831420 |
| effect of electron donor and solution chemistry on products of dissimilatory reduction of technetium by shewanella putrefaciens. | to help provide a fundamental basis for use of microbial dissimilatory reduction processes in separating or immobilizing (99)tc in waste or groundwaters, the effects of electron donor and the presence of the bicarbonate ion on the rate and extent of pertechnetate ion [tc(vii)o(4)(-)] enzymatic reduction by the subsurface metal-reducing bacterium shewanella putrefaciens cn32 were determined, and the forms of aqueous and solid-phase reduction products were evaluated through a combination of high-r ... | 2000 | 10831424 |
| enrichment of geobacter species in response to stimulation of fe(iii) reduction in sandy aquifer sediments. | engineered stimulation of fe(iii) has been proposed as a strategy to enhance the immobilization of radioactive and toxic metals in metal-contaminated subsurface environments. therefore, laboratory and field studies were conducted to determine which microbial populations would respond to stimulation of fe(iii) reduction in the sediments of sandy aquifers. in laboratory studies, the addition of either various organic electron donors or electron shuttle compounds stimulated fe(iii) reduction and re ... | 2000 | 10833228 |
| polyphasic taxonomic approach in the description of alishewanella fetalis gen. nov., sp. nov., isolated from a human foetus. | a taxonomically unique bacterium is described on the basis of a physiological and biochemical characterization, fatty acid profiling and sequence analyses of 16s rrna and gyrase b (gyrb) genes. this non-motile, non-fermentative bacterium was isolated from a human foetus in uppsala, sweden, and originally misidentified as a shewanella putrefaciens by conventional biochemical testing. the bacterium grew well at mesophilic temperatures with optimum growth at 37 degrees c. it was facultatively anaer ... | 2000 | 10843055 |
| identification of a novel gene, fimv, involved in twitching motility in pseudomonas aeruginosa. | transposon mutagenesis was used to identify a new locus required for twitching motility in pseudomonas aeruginosa. four tn5-b21 mutants which lacked twitching motility and a fifth which exhibited impaired motility were found to map to the same kpn:i restriction fragment at approximately 40 min on the p. aeruginosa genome. cloning and sequencing studies showed that all five transposon insertions occurred within the same 2.8 kb orf, which was termed fimv. the product of this gene has a putative pe ... | 2000 | 10846211 |
| do stresses encountered during the smoked salmon process influence the survival of the spoiling bacterium shewanella putrefaciens? | the influence of different treatments (i.e. cold, nacl, phenol and anaerobiosis) encountered during the smoked salmon process was studied by analysing the survival capacity of two shewanella putrefaciens strains (cip 69.29 and j13.1). our results indicated that only the salt stress was critical for the survival of s. putrefaciens. nevertheless, both strains of s. putrefaciens grown at low temperatures developed a cross-protection to a lethal nacl treatment. to our knowledge, this is the first re ... | 2000 | 10849272 |
| cyanobacterial sulfide-quinone reductase: cloning and heterologous expression. | the gene encoding sulfide-quinone reductase (sqr; e.c.1.8.5.'), the enzyme catalyzing the first step of anoxygenic photosynthesis in the filamentous cyanobacterium oscillatoria limnetica, was cloned by use of amino acid sequences of tryptic peptides as well as sequences conserved in the rhodobacter capsulatus sqr and in an open reading frame found in the genome of aquifex aeolicus. sqr activity was also detected in the unicellular cyanobacterium aphanothece halophytica following sulfide inductio ... | 2000 | 10852862 |
| identification and characterization of a novel cytochrome c(3) from shewanella frigidimarina that is involved in fe(iii) respiration. | shewanella frigidimarina ncimb400 is a non-fermenting, facultative anaerobe from the gamma group of proteobacteria. when grown anaerobically this organism produces a wide variety of periplasmic c-type cytochromes, mostly of unknown function. we have purified a small, acidic, low-potential tetrahaem cytochrome with similarities to the cytochromes c(3) from sulphate-reducing bacteria. the n-terminal sequence was used to design pcr primers and the ccta gene encoding cytochrome c(3) was isolated and ... | 2000 | 10861223 |
| a new bacterial white spot syndrome (bwss) in cultured tiger shrimp penaeus monodon and its comparison with white spot syndrome (wss) caused by virus. | this paper describes a new bacterial white spot syndrome (bwss) in cultured tiger shrimp penaeus monodon. the affected shrimp showed white spots similar to those caused by white spot syndrome virus (wssv), but the shrimp remained active and grew normally without significant mortalities. the study revealed no evidence of wssv infection using electron microscopy, histopathology and nested polymerase chain reaction. electron microscopy indicated bacteria associated with white spot formation, and wi ... | 2000 | 10907134 |
| applicability of an arrhenius model for the combined effect of temperature and co(2) packaging on the spoilage microflora of fish. | the temperature behavior of the natural microflora on the mediterranean fish red mullet (mullus barbatus) was examined as a case study. the growth of the spoilage bacteria pseudomonas spp., shewanella putrefaciens, brochothrix thermosphacta, and lactic acid bacteria was modeled as a function of temperature and the concentration of carbon dioxide in modified atmosphere packaging. combined models were developed and comparatively assessed based on polynomial, belehradek, and arrhenius equations. th ... | 2000 | 10919817 |
| a new class of glutamate dehydrogenases (gdh). biochemical and genetic characterization of the first member, the amp-requiring nad-specific gdh of streptomyces clavuligerus. | a new class of glutamate dehydrogenase (gdh) is reported. the gdh of streptomyces clavuligerus was purified to homogeneity and characterized. it has a native molecular mass of 1,100 kda and exists as an alpha(6) oligomeric structure composed of 183-kda subunits. gdh, which requires amp as an essential activator, shows a maximal rate of catalysis in 100 mm phosphate buffer, ph 7.0, at 30 degrees c. under these conditions, gdh displayed hyperbolic behavior toward ammonia (k(m), 33 mm) and sigmoida ... | 2000 | 10924516 |
| pressure response in deep-sea piezophilic bacteria. | several piezophilic bacteria have been isolated from deep-sea environments under high hydrostatic pressure. taxonomic studies of the isolates showed that the piezophilic bacteria are not widely distributed in terms of taxonomic positions, and all were assigned to particular branches of the proteobacteria gamma-subgroup. a pressure-regulated operon from piezophilic bacteria of the genus shewanella, s. benthica and s. violacea, was cloned and sequenced, and downstream of this operon another pressu ... | 1999 | 10941789 |
| design and application of a rapid screening technique for isolation of selenite reduction-deficient mutants of shewanella putrefaciens. | a rapid screening technique for isolation of selenite (se(iv)) reduction-deficient (ser) mutants was developed and used to identify four ser mutants of shewanella putrefaciens. two ser mutants were unable to grow anaerobically on fumarate, nitrate or nitrite. two other ser mutants were unable to grow anaerobically on all compounds tested as sole terminal electron acceptor. previously isolated mn(iv) reduction-deficient mutants displayed ser-positive phenotypes and reduced se(iv) at wild-type rat ... | 2000 | 10950189 |
| fe(iii) reduction activity and cytochrome content of shewanella putrefaciens grown on ten compounds as sole terminal electron acceptor. | shewanella putrefaciens was grown on a series of ten alternate compounds as sole terminal electron acceptor. each cell type was analyzed for fe(iii) reduction activity, absorbance maxima in reduced-minus-oxidized difference spectra and heme-containing protein content. high-rate fe(iii) reduction activity, pronounced difference maxima at 521 and 551 nm and a predominant 29.3 kda heme-containing protein expressed by cells grown on fe(iii), mn(iv), u(vi), so3(2-) and s2o3(2-), but not by cells grow ... | 2000 | 10950190 |
| expression of a tetraheme protein, desulfovibrio vulgaris miyazaki f cytochrome c(3), in shewanella oneidensis mr-1. | cytochrome c(3) from desulfovibrio vulgaris miyazaki f was successfully expressed in the facultative aerobe shewanella oneidensis mr-1 under anaerobic, microaerophilic, and aerobic conditions, with yields of 0.3 to 0.5 mg of cytochrome/g of cells. a derivative of the broad-host-range plasmid prk415 containing the cytochrome c(3) gene from d. vulgaris miyazaki f was used for transformation of s. oneidensis mr-1, resulting in the production of protein product that was indistinguishable from that p ... | 2000 | 10966450 |
| identification of the active site acid/base catalyst in a bacterial fumarate reductase: a kinetic and crystallographic study. | the active sites of respiratory fumarate reductases are highly conserved, indicating a common mechanism of action involving hydride and proton transfer. evidence from the x-ray structures of substrate-bound fumarate reductases, including that for the enzyme from shewanella frigidimarina [taylor, p., pealing, s. l., reid, g. a., chapman, s. k., and walkinshaw, m. d. (1999) nat. struct. biol. 6, 1108-1112], indicates that the substrate is well positioned to accept a hydride from n5 of the fad. how ... | 2000 | 10978153 |
| capd, swimming in shewanella. | | 2000 | 10978422 |
| catalysis in fumarate reductase. | in the absence of oxygen many bacteria are able to utilise fumarate as a terminal oxidant for respiration. in most known organisms the fumarate reductases are membrane-bound iron-sulfur flavoproteins but shewanella species produce a soluble, periplasmic flavocytochrome c(3) that catalyses this reaction. the active sites of all fumarate reductases are clearly conserved at the structural level, indicating a common mechanism. the structures of fumarate reductases from two shewanella species have be ... | 2000 | 11004445 |
| application of a systematic experimental procedure to develop a microbial model for rapid fish shelf life predictions. | a systematic experimental procedure for fish shelf-life modelling was used to develop a model for predicting the quality of fish in the chill chain. for this, the growth of the naturally occurring bacteria pseudomonads, shewanella putrefaciens, enterobacteriaceae, lactic acid bacteria and yeasts, on gilt-head seabream (sparus aurata), was studied at temperatures from 0 to 15 degrees c. the results from the microbiological, organoleptical and chemical analysis conducted on naturally contaminated ... | 2000 | 11016607 |
| control of foodborne pathogens during sufu fermentation and aging. | control of the foodborne pathogens escherichia coli o157:h7, salmonella typhimurium, staphylococcus aureus, and listeria monocytogenes during sufu fermentation was evaluated. before fermentation, pathogens were inoculated onto tofu (substrate for sufu) at 5 log cfu/g or 3 log cfu/g, and starter culture (actinomucor elegans) was inoculated at 3 log cfu/g. after 2 days of fermentation at 30 degrees c, the four pathogens reached 7 to 9 log cfu/g, and the mold count reached 6 to 7 log cfu/g. after f ... | 2000 | 11029011 |
| glutamine synthetase gene expression at elevated hydrostatic pressure in a deep-sea piezophilic shewanella violacea. | a glutamine synthetase gene (glna) was isolated from a deep-sea piezophilic bacterium, shewanella violacea strain dss12. a 7.5-kb saci fragment containing the complete glna gene was cloned and sequenced. the glna gene was found to encode a protein consisting of 469 amino acid residues, showing 75.0% identity to the glutamine synthetase of escherichia coli. primer extension analyses revealed two transcription initiation sites in glna and expression from each site was positively regulated by press ... | 2000 | 11040434 |
| the synergistic effect of excimer and low-pressure mercury lamps on the disinfection of flowing water. | microorganisms in flowing water were disinfected by uv radiation from two excimer (excited dimer) lamps (emitting at 172 and 222 nm) in combination with two low-pressure mercury lamps (emitting at 254 nm). synergies were investigated among the three types of radiation in the treatment of water spiked in turn with escherichia coli, listeria innocua, shewanella putrefaciens, and spores of bacillus subtilis and bacillus cereus. synergy was demonstrated between radiations at 222 and 254 nm in the tr ... | 2000 | 11079695 |
| [recent advances in tetrodotoxin research]. | one century has passed since fugu toxin was named tetrodotoxin (ttx) by tahara. chemical problems such as crystallization of tetrodotoxin and subsequent structure determination were solved by research groups headed by tsuda, hirata, woodward, and mosher. the international symposium on the chemistry of natural products in kyoto (1964) was well known as symposium which the structure of ttx was internationally clarified. since the first isolation of toxin from taricha torosa (imori) as natural sour ... | 2000 | 11082696 |
| porphyromonas gingivalis dpp-7 represents a novel type of dipeptidylpeptidase. | a novel dipeptidylpeptidase (dpp-7) was purified from the membrane fraction of porphyromonas gingivalis. this enzyme, with an apparent molecular mass of 76 kda, has the specificity for both aliphatic and aromatic residues in the p1 position. although it belongs to the serine class of peptidases, it does not resemble other known dipeptidylpeptidases. interestingly, the amino acid sequence around the putative active site serine residue shows significant similarity to the c-terminal region of the s ... | 2001 | 11096098 |
| production of eicosapentaenoic acid by a recombinant marine cyanobacterium, synechococcus sp. | the eicosapentaenoic acid (epa) synthesis gene cluster from an epa-producing bacterium, shewanella sp. scrc-2738, was cloned into a broad-host range vector, pjrd215, and then introduced into a marine cyanobacterium, synechococcus sp. nkbg15041c, by conjugation. the transconjugant cyanobacteria produced 3.7 +/- 0.2% (2.24 +/- 0.13 mg/l) epa (n-3) and 2.5 +/- 0.2% (1.49 +/- 0.06 mg/l) eicosatetraenoic acid (n-3) of the total fatty acids when the cells were cultured at 23 degrees c at a light inten ... | 2000 | 11104010 |
| isolation and piezoresponse of the rpoa gene encoding the rna polymerase alpha subunit from the deep-sea piezophilic bacterium shewanella violacea. | the rpoa gene encoding the alpha subunit of rna polymerase from the deep-sea piezophilic bacterium shewanella violacea dss12 was cloned and sequenced. the rpoa gene was found to encode a polypeptide consisting of 329 amino acids with a molecular mass of 36238 da. s. violacea alpha protein was expressed in a ts escherichia coli mutant, to confirm whether the rpoa gene is functional. it complemented this mutation, indicating a chimeric rna polymerase is assembled at the non-permissive temperature. ... | 2000 | 11111034 |
| role for outer membrane cytochromes omca and omcb of shewanella putrefaciens mr-1 in reduction of manganese dioxide. | shewanella putrefaciens mr-1 can use a wide variety of terminal electron acceptors for anaerobic respiration, including certain insoluble manganese and iron oxides. to examine whether the outer membrane (om) cytochromes of mr-1 play a role in mn(iv) and fe(iii) reduction, mutants lacking the om cytochrome omca or omcb were isolated by gene replacement. southern blotting and pcr confirmed replacement of the omca and omcb genes, respectively, and reverse transcription-pcr analysis demonstrated los ... | 2001 | 11133454 |
| the gdhb gene of pseudomonas aeruginosa encodes an arginine-inducible nad(+)-dependent glutamate dehydrogenase which is subject to allosteric regulation. | the nad(+)-dependent glutamate dehydrogenase (nad-gdh) from pseudomonas aeruginosa pao1 was purified, and its amino-terminal amino acid sequence was determined. this sequence information was used in identifying and cloning the encoding gdhb gene and its flanking regions. the molecular mass predicted from the derived sequence for the encoded nad-gdh was 182.6 kda, in close agreement with that determined from sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme (180 kda ... | 2001 | 11133942 |
| automated nanoflow liquid chromatography/tandem mass spectrometric identification of proteins from shewanella putrefaciens separated by two-dimensional polyacrylamide gel electrophoresis. | the implementation of nanoflow liquid chromatography offers unique opportunities for automation of proteomics research. we demonstrate that automated nanoflow lc/ms/ms allowed the unambiguous identification of proteins from the omnipotent bacterium shewanella putrefaciens, based on similarity searches against the completely determined genome of related microorganisms and against non-redundant databases. total protein extracts were separated by 2-dimensional polyacrylamide electrophoresis. only 1 ... | 2001 | 11135424 |
| humin and anthroquinone reduction by an anaerobic microbe. | | 2000 | 11145107 |
| shewanella putrefaciens hand infection. | | 2000 | 11147445 |
| identification of a plasmid-encoded gene from haemophilus ducreyi which confers nad independence. | members of the family pasteurellaceae are classified in part by whether or not they require an nad supplement for growth on laboratory media. in this study, we demonstrate that this phenotype can be determined by a single gene, nadv, whose presence allows nad-independent growth of haemophilus influenzae and actinobacillus pleuropneumoniae. this gene was cloned from a 5.2-kb plasmid which was previously shown to be responsible for nad independence in haemophilus ducreyi. when transformed into a. ... | 2001 | 11157928 |
| mtrc, an outer membrane decahaem c cytochrome required for metal reduction in shewanella putrefaciens mr-1. | shewanella putrefaciens is a facultative anaerobe that can use metal oxides as terminal electron acceptors during anaerobic respiration. two proteins, mtrb and cct, have been identified that are specifically involved in metal reduction. analysis of s. putrefaciens mutants deficient in metal reduction led to the identification of two additional proteins that are involved in this process. mtra is a periplasmic decahaem c-type cytochrome that appears to be part of the electron transport chain, whic ... | 2001 | 11169112 |
| the biotechnological potential of piezophiles. | microorganisms that prefer high-pressure conditions are termed piezophiles (previously termed barophiles). the molecular basis of piezophily is now being investigated extensively focusing on aspects of gene regulation and the function of certain proteins in deep-sea isolates. little attention has been paid, however, to the potential biotechnological applications of piezophiles compared with other extremophiles. based on the fundamental knowledge available, we will try to answer the following que ... | 2001 | 11179803 |
| control of foodborne pathogens during sufu fermentation and aging. | control of the foodborne pathogens escherichia coli o157:h7, salmonella typhimurium, staphylococcus aureus, and listeria monocytogenes during sufu fermentation was evaluated. before fermentation, pathogens were inoculated onto tofu (substrate for sufu) at 5 log cfu/g or 3 log cfu/g, and starter culture (actinomucor elegans) was inoculated at 3 log cfu/g. after 2 days of fermentation at 30 degrees c, the four pathogens reached 7 to 9 log cfu/g, and the mold count reached 6 to 7 log cfu/g. after f ... | 2000 | 11192025 |