| priming effects on pah degradation and ecotoxicity during a phytoremediation experiment. | an experiment was conducted to distinguish priming effects from the effects of phytoremediation of a creosote-polluted soil. the concentration of 13 polycyclic aromatic hydrocarbons (pahs), and their combined soil toxicity (using four bioassays), was determined on recently excavated, homogenized soil and on such soil subjected to a time-course phytoremediation experiment with lucerne. the results showed a high priming effect, with minor positive and synergistic effects of planting and fertilizat ... | 2004 | 14720484 |
| continuous culture of photobacterium. | the design and performance characteristics of a small volume (20 ml) continuous culture device for the cultivation of luminous bacteria are described. this simply constructed device can be used to supply luminescent bacteria with constant properties for either laboratory use or the assay of environmental pollutants. furthermore, bacteria can be deployed to make sensitive (<1 nm) oxygen measurements. the culture device may be configured, alone or in combination, as a chemostat, turbidostat or a " ... | 2004 | 15093217 |
| on line biomonitors used as a tool for toxicity reduction evaluation of in situ groundwater remediation techniques. | success of groundwater remediation is typically controlled via snapshot analysis of selected chemical substances or physical parameters. biological parameters, i.e. ecotoxicological assays, are rarely employed. hence the aim of the study was to develop a bioassay tool, which allows an on line monitoring of contaminated groundwater, as well as a toxicity reduction evaluation (tre) of different remediation techniques in parallel and may furthermore be used as an additional tool for process control ... | 2004 | 15142606 |
| matrix-assisted laser desorption/ionization-time of flight-mass spectrometry of lipopolysaccharide species separated by slab-polyacrylamide gel electrophoresis: high-resolution separation and molecular weight determination of lipooligosaccharides from vibrio fischeri strain hmk. | we recently demonstrated that the combined use of lipopolysaccharide (lps) reverse staining and high-efficiency passive elution techniques can be successfully used as a suitable interface between lps slab-gel separation and electrospray ionization-mass spectrometry (esi-ms) of lps-derived oligosaccharides. here, we extend our micropurification strategy for the analysis of o-deacylated lps forms from vibrio fischeri hmk after recovery from single reverse-stained lps bands using matrix-assisted la ... | 2004 | 15273999 |
| toxicity of a commercial herbicide containing terbutryn and triasulfuron to seabream (sparus aurata l.) larvae: a comparison with the microtox test. | the present study aimed to compare the sensitivity of larvae of the gilthead seabream (sparus aurata), a valuable fish species of the spanish south atlantic littoral, with the extensively used microtox test on a commercial herbicide formulation containing terbutryn (59.4%) and triasulfuron (0.6%). to this purpose, mortality displayed by endogenous feeding s. aurata larvae exposed during 72 h post-hatching to nominal concentrations of the commercial formulation and bioluminescence of the marine b ... | 2004 | 15327877 |
| toxicity of metals and metal mixtures: analysis of concentration and time dependence for zinc and copper. | the toxic effects of heavy metals, zinc and copper, in unary and binary solutions were studied using the microtox acute toxicity test which relies upon the attenuation of light intensity emitted by vibrio fischeri. the toxic effect gamma (ratio of the light intensity lost at time t to the light intensity remaining at time t) of zinc could be related to its concentration [x] by a two-parameter equation gamma=a(1-exp(-b[x])), where parameter a was a function of time and b equal to 0.88l/mg. the to ... | 2004 | 15350416 |
| tropical ecotoxicity testing with ceriodaphnia cornuta. | the sai gon-dong nai river system in southern vietnam is of great social and economic importance yet receives a large amount of industrial, domestic, and agricultural discharges. toxicity assessment has started to become an issue in vietnam, and it is important to employ a test system that is appropriate for typical vietnamese conditions with a species that is representative of the invertebrates living in its aquatic ecosystems. the aim of this study was to develop and to validate an ecotoxicity ... | 2004 | 15352266 |
| screening for antibacterial activity in 72 species of wood-colonizing fungi by the vibrio fisheri bioluminescence method. | resistance of pathogenic bacteria to antibiotics leads scientists to discover new antibacterial drugs. ninety samples of wood-colonizing fungi were cultivated on agar plates, and their extracts tested for antibacterial activity using the vibrio fischeri bioluminescence test. two fungi species, serpula lacrymans and nectria vilior, were found to be a potential new source of thermostable antibiotics. vibrio fischeri bioluminescence test was found to be a useful method for antibacterial activity sc ... | 2004 | 15378528 |
| n-sulfonyl homoserine lactones as antagonists of bacterial quorum sensing. | a series of 11 new analogues of n-acylhomoserine lactones in which the carboxamide bond was replaced by a sulfonamide one, has been synthesised. these compounds were evaluated for their ability to competitively inhibit the action of 3-oxohexanoyl-l-homoserine lactone, the natural ligand of the quorum sensing transcriptional regulator luxr, which in turn activates expression of bioluminescence in the model bacterium vibrio fischeri. several compounds were found to display antagonist activity. mol ... | 2004 | 15380216 |
| enzyme classification by ligand binding. | the problem of assigning a biochemical function to newly discovered proteins has been traditionally approached by expert enzymological analysis, sequence analysis, and structural modeling. in recent years, the appearance of databases containing protein-ligand interaction data for large numbers of protein classes and chemical compounds have provided new ways of investigating proteins for which the biochemical function is not completely understood. in this work, we introduce a method that utilizes ... | 2004 | 15476211 |
| monitoring genotoxicity during the photocatalytic degradation of p-nitrophenol. | p-nitrophenol is a common structural unit of many pesticides and was chosen as a model compound to monitor genotoxicity during photocatalytic degradation. the genotoxicity of p-nitrophenol (pnp) and its breakdown products was measured using a bioluminescent bacterial bioassay, vitotox. the genotoxic potential decreased with the concomitant photocatalytic degradation of the parent pnp concentration. the rate of genotoxicity reduction was slower than the rate of removal of the parent pnp, due to t ... | 2004 | 15478172 |
| eilatox-oregon workshop: blind study evaluation of vitotox test with genotoxic and cytotoxic sample library. | in order to assess the robustness, sensitivity and specificity of a recently developed vitotox test, 17 blind coded chemicals and three environmental water samples were tested at the eilatox-oregon workshop using the thermo electron vitotox kit. the vitotox test is a rapid geno- and cytotoxicity test using standard 96- or 384-well microtitre plates. the genotoxicity test is based on two genetically modified salmonella typhimurium strains containing bacterial luciferase operon from vibrio fisheri ... | 2004 | 15478175 |
| enhancement of the multi-channel continuous monitoring system through the use of xenorhabdus luminescens lux fusions. | the enhancement of the multi-channel continuous toxicity monitoring system developed previously was studied. to achieve better and more stable results from the system, the use of thermo-lux fusion strains that express the luxcdabe genes from xenorhabdus luminescens was evaluated. a total of six recombinant escherichia coli strains with the promoters from three oxidative-stress responsive genes, i.e. the katg, soda and pqi-5 genes, fused to either the lux genes from vibrio fischeri or x. luminesc ... | 2004 | 15494228 |
| comparison of different advanced oxidation process to reduce toxicity and mineralisation of tannery wastewater. | many organic compounds contained in wastewater are resistant to conventional chemical and/or biological treatment. because of this reason different degradation techniques are studied as an alternative to biological and classical physico-chemical processes. advanced oxidation processes (aops) probably have developed to become the best options in the near future. aop while making use of different reaction systems, are all characterised by the same chemical feature: production of oh radicals (*oh). ... | 2004 | 15497865 |
| comparative toxic effects of formulated simazine on vibrio fischeri and gilthead seabream (sparus aurata l.) larvae. | the use of early life stage (els) tests is a useful tool in risk assessment. the purpose of this study was to compare the sensitivity of the seabream (sparus aurata) larvae with the extensively used microtox test on a commercial formulation containing simazine, an s-triazine herbicide. to this end, survival, growth and histopathological changes displayed by seabream yolk sac larvae exposed during 72 h post-hatching to nominal concentrations of the commercial preparation up to its saturating conc ... | 2004 | 15519419 |
| biography of e. p. greenberg. | | 2004 | 15520366 |
| no means 'yes' in the squid-vibrio symbiosis: nitric oxide (no) during the initial stages of a beneficial association. | during colonization of the euprymna scolopes light organ, symbiotic vibrio fischeri cells aggregate in mucus secreted by a superficial ciliated host epithelium near the sites of eventual inoculation. once aggregated, symbiont cells migrate through ducts into epithelium-lined crypts, where they form a persistent association with the host. in this study, we provide evidence that nitric oxide synthase (nos) and its product nitric oxide (no) are active during the colonization of host tissues by v. f ... | 2004 | 15527494 |
| microbial factor-mediated development in a host-bacterial mutualism. | tracheal cytotoxin (tct), a fragment of the bacterial surface molecule peptidoglycan (pgn), is the factor responsible for the extensive tissue damage characteristic of whooping cough and gonorrhea infections. here, we report that vibrio fischeri also releases tct, which acts in synergy with lipopolysaccharide (lps) to trigger tissue development in its mutualistic symbiosis with the squid euprymna scolopes. as components of pgn and lps have commonly been linked with pathogenesis in animals, these ... | 2004 | 15539604 |
| the effect of temperature and nacl concentration on the kinetic method of toxicity determination using vibrio fischeri. | in this paper the effect of temperature and nacl concentration on the kinetic method of toxicity determination using vibrio fischeri was studied for 50 ppm zn(2+). this work shows that both nacl concentration and temperature affect the kinetics of toxicity as well as the luminescence of the bacteria, and hence these are important factors that need to be considered in the development of a miniaturised portable instrument. furthermore, this work shows that the conditions for which the kinetic test ... | 2004 | 15568042 |
| biosensor-based diagnostics of contaminated groundwater: assessment and remediation strategy. | shallow groundwater beneath a former airfield site in southern england has been heavily contaminated with a wide range of chlorinated solvents. the feasibility of using bacterial biosensors to complement chemical analysis and enable cost-effective, and focussed sampling has been assessed as part of a site evaluation programme. five different biosensors, three metabolic (vibrio fischeri, pseudomonas fluorescens 10568 and escherichia coli hb101) and two catabolic (pseudomonas putida tva8 and e. co ... | 2005 | 15620594 |
| study on the toxicity of binary equitoxic mixtures of metals using the luminescent bacteria vibrio fischeri as a biological target. | results from two mathematical approaches to predict the toxicity of all the possible binary equitoxic mixtures of co, cd, cu, zn and pb were compared to the observed toxicity of these mixtures to vibrio fischeri bacteria. combined effect of the metals was found to be antagonistic for co-cd, cd-zn, cd-pb and cu-pb, synergistic for co-cu and zn-pb and merely additive in other cases, revealing a complex pattern of possible interactions. besides, cd appears much less toxic to the bacterial model tha ... | 2005 | 15620748 |
| ecotoxicological evaluation of the additive butylated hydroxyanisole using a battery with six model systems and eighteen endpoints. | the occurrence and fate of additives in the aquatic environment is an emerging issue in environmental chemistry. this paper describes the ecotoxicological effects of the commonly used additive butylated hydroxyanisole (bha) using a test battery, comprising of several different organisms and in vitro test systems, representing a proportion of the different trophic levels. the most sensitive system to bha was the inhibition of bioluminescence in vibrio fischeri bacteria, which resulted in an acute ... | 2004 | 15642642 |
| assessment of the toxicity of triasulfuron and its photoproducts using aquatic organisms. | the toxicological effects of the sulfonylurea herbicide triasulfuron and its photoproducts were assessed on four aquatic organisms. toxicity varied with tested organism and with triasulfuron irradiation time. triasulfuron and its photoproducts had no significant effects on the crustacean (cladocera) daphnia magna (causing 50% effective concentration [ec50] [48 h] = 49 +/- 1 mg/l) and the marine bacteria vibrio fischeri (ec50 [30 min] > 100 mg/l). in contrast, primary producers (the duckweed lemn ... | 2004 | 15648757 |
| comparative toxicity of oil, dispersant, and oil plus dispersant to several marine species. | dispersants are a preapproved chemical response agent for oil spills off portions of the u.s. coastline, including the texas-louisiana coast. however, questions persist regarding potential environmental risks of dispersant applications in nearshore regions (within three nautical miles of the shoreline) that support dense populations of marine organisms and are prone to spills resulting from human activities. to address these questions, a study was conducted to evaluate the relative toxicity of t ... | 2004 | 15648769 |
| directed evolution of vibrio fischeri luxr for increased sensitivity to a broad spectrum of acyl-homoserine lactones. | luxr-type transcriptional regulators play key roles in quorum-sensing systems that employ acyl-homoserine lactones (acyl-hsls) as signal molecules. these proteins mediate quorum control by changing their interactions with rna polymerase and dna in response to binding their cognate acyl-hsl. the evolutionarily related luxr-type proteins exhibit considerable diversity in primary sequence and in their response to acyl-hsls having acyl groups of differing length and composition. little is known abou ... | 2005 | 15660998 |
| extent of sonochemical degradation and change of toxicity of a pharmaceutical precursor (triphenylphosphine oxide) in water as a function of treatment conditions. | the degradation of triphenylphosphine oxide (tppo) in water, a toxic compound typically found in effluents from the pharmaceutical industry, by means of ultrasonic irradiation at 20 khz has been investigated with emphasis on the effect of various parameters on conversion and acute toxicity. experiments were carried out at liquid volumes of 50 and 80 ml, electric power outputs of 125, 187.5 and 250 w, initial tppo concentrations of 10, 100 and 350 mg/l and temperatures of 5, 20, 35, 50 and 70 deg ... | 2005 | 15661285 |
| effect of nannochloris sp. on the toxicity of four algae. | the effect of nannochloris sp. on the toxicity of cultures of four algae was evaluated using a microtox 500 that measures the effect on a light-producing bacterium, vibrio fischeri. cultures of four algae produced a toxic effect, but in the presence of nannochloris sp., the effect was reversed, and a stimulatory effect was observed. the effect was tested for microcystis aeroginosa, cyclotella menengheniana, scenedesmus dimorphis, and lyngbya sp. using cultures obtained from the university of tex ... | 2005 | 15663306 |
| the use of microtox to assess toxicity removal of industrial effluents from the industrial district of camaçari (ba, brazil). | the treatment efficiency, as toxicity removal, of complex effluents from the industrial district of camaçari (ba, brazil), after biological treatment with activated sludge was evaluated using microtox. samples of the equalised effluent (ee) were collected prior to treatment together with samples of the treated effluent (te), which remained 24 h in the treatment plant. rehydrated colonies of vibrio fischeri were exposed to sequential dilutions of ee and te to assess luminosity interference. value ... | 2005 | 15667847 |
| lutetium speciation and toxicity in a microbial bioassay: testing the free-ion model for lanthanides. | the validity of the free-ion model (fim) for the element lutetium (lu), a member of the lanthanides, was assessed in experiments with the bacterium vibrio fischeri. the fim is mainly based on divalent metals and synthetic ligands and has not yet been validated for the trivalent lanthanides. the bioluminescence response of v. fischeri was studied at different lu concentrations in the presence and absence of natural and synthetic organic ligands [citrate, malate, oxalate, acetate, ethylenediaminet ... | 2004 | 15669317 |
| qstr with extended topochemical atom indices. part 5: modeling of the acute toxicity of phenylsulfonyl carboxylates to vibrio fischeri using genetic function approximation. | in continuation of our recent efforts to model the acute toxicity of 56 phenylsulfonyl carboxylates to vibrio fischeri using principal component factor analysis, the present paper deals with modeling of the same data set with extended topochemical atom (eta) indices using genetic function approximation (gfa) as the statistical tool. the statistical quality of the best model using eta descriptors is as follows: n=56, q2=0.771, ra2=0.861, r=0.935, f=69.0 (df5,50), s=0.172, avres=0.128. this equati ... | 2005 | 15670927 |
| metolachlor photodegradation study in aqueous media under natural and simulated solar irradiation. | to elucidate the photochemical behavior of pesticide metolachlor, degradation was carried out in aqueous media of different compositions such as sea, river, lake, and distilled water under natural and simulated solar irradiation. in addition, the effect of important constituents of natural water such as dissolved organic matter (dom, isolated from pamvotis lake) and nitrate ions was also examined. it was found that photodegradation proceeds via a pseudo-first-order reaction in all cases. the pre ... | 2005 | 15686422 |
| effects of nutrient and temperature on degradation of petroleum hydrocarbons in contaminated sub-antarctic soil. | mesocosm studies using sub-antarctic soil artificially contaminated with diesel or crude oil were conducted in kerguelen archipelago (49 degrees 21' s, 70 degrees 13' e) in an attempt to evaluate the potential of a bioremediation approach in high latitude environments. all mesocosms were sampled on a regular basis over six months period. soils responded positively to temperature increase from 4 degrees c to 20 degrees c, and to the addition of a commercial oleophilic fertilizer containing n and ... | 2005 | 15686763 |
| complete genome sequence of vibrio fischeri: a symbiotic bacterium with pathogenic congeners. | vibrio fischeri belongs to the vibrionaceae, a large family of marine gamma-proteobacteria that includes several dozen species known to engage in a diversity of beneficial or pathogenic interactions with animal tissue. among the small number of pathogenic vibrio species that cause human diseases are vibrio cholerae, vibrio parahaemolyticus, and vibrio vulnificus, the only members of the vibrionaceae that have had their genome sequences reported. nonpathogenic members of the genus vibrio, includi ... | 2005 | 15703294 |
| sensitivity of dark mutants of various strains of luminescent bacteria to reactive oxygen species. | recent studies indicated that bioluminescence of the marine bacterium vibrio harveyi may both stimulate dna repair and contribute to detoxification of deleterious oxygen derivatives. therefore, it was also proposed that these reactions can be considered biological roles of bacterial luminescence and might act as evolutionary drives in development of luminous systems. however, experimental evidence for the physiological role of luciferase in protection of cells against oxidative stress has been d ... | 2005 | 15717160 |
| the ability of white-rot fungi to degrade the endocrine-disrupting compound nonylphenol. | phanerochaete chrysosporium, pleurotus ostreatus, trametes versicolor and bjerkandera sp. bol13 were tested for their ability to degrade the endocrine-disrupting compound nonylphenol at an initial concentration of 100 mg l-1. the highest removals were achieved with t. versicolor and bjerkandera sp. bol13, which were able to degrade 97 mg l-1 and 99 mg l-1 of nonylphenol in 25 days of incubation, respectively. nonylphenol removal was associated with the production of laccase by t. versicolor, but ... | 2004 | 15735968 |
| magnesium promotes flagellation of vibrio fischeri. | the bacterium vibrio fischeri requires bacterial motility to initiate colonization of the hawaiian squid euprymna scolopes. once colonized, however, the bacterial population becomes largely unflagellated. to understand environmental influences on v. fischeri motility, we investigated migration of this organism in tryptone-based soft agar media supplemented with different salts. we found that optimal migration required divalent cations and, in particular, mg2+. at concentrations naturally present ... | 2005 | 15743954 |
| effects of triclosan on various aquatic organisms. | triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) is widely used as an antibacterial agent in various industrial products, such as textile goods, soap, shampoo, liquid toothpaste and cosmetics, and often detected in wastewater effluent. however, there is a paucity of data on the toxicity of triclosan and its effects on aquatic organisms. in this study, the acute toxicity of triclosan to the microtox bacterium (vibrio fischeri), a microalga (selenastrum capricornutum), a crustacean (ceriodaph ... | 2004 | 15746894 |
| radiolytic degradation of the herbicide dicamba for environmental protection. | the radiolytic degradation of the widely used herbicide dicamba (3,6-dichloro-2-methoxybenzoic acid), employing gamma irradiation in laboratory batch conditions and with a beam of accelerated electrons in flow-through installation, was investigated. the effects of dose magnitude, ozone or hydrogen peroxide in irradiated solution, and scavengers such as nitrate and hydrogen carbonate on the effectiveness of dicamba decomposition and the products formed were investigated. changes in the toxicity o ... | 2005 | 15750781 |
| chemical and ecotoxicological assessment of polycyclic aromatic hydrocarbon--contaminated sediments of the niger delta, southern nigeria. | the extent of environmental contamination and sources of polycyclic aromatic hydrocarbons (pahs) compounds to sediments of the niger delta, nigeria were assessed using combined chemical analysis and toxicity bioassay techniques. concentrations of two- to six-ring pahs of molecular mass 128-278 and toxicity to vibrio fischeri and lemna minor are considered in this investigation. levels of the sum of the 16 usepa priority pollutant pahs varied from 20.7 to 72.1 ng/g dry weight. sediment pah levels ... | 2005 | 15752497 |
| screening test battery for pharmaceuticals in urine and wastewater. | a test battery for identifying ecotoxicological hazards was applied to six pharmaceuticals (carbamazepine, diclofenac, ethinylestradiol, ibuprofen, propranolol, and sulfamethoxazole), to their mixtures, and to urine spiked with pharmaceuticals to test the suitability of biotests for screening urine and wastewater and for monitoring the efficiency of wastewater treatment. the test battery comprised the bioluminescence inhibition test with vibrio fischeri, the yeast estrogen screen, and a photosyn ... | 2005 | 15779777 |
| evaluation of toxic properties of industrial wastewater using on-line respirometry. | an on-line respirometric biosensor using activated sludge microorganisms was used in this work for the assessment of toxic properties of industrial effluents and for the evaluation of their effect on the performance of a municipal wastewater treatment plant. continuous monitoring of combined industrial discharges was carried out for a period of six months, and increased toxicity values were observed during the evening times and the weekends, possibly due to the discharge of partially treated was ... | 2005 | 15792305 |
| a novel method for evaluating bioavailability of polycyclic aromatic hydrocarbons in sediments of an urban stream. | hydrophobic organic pollutants in urban wet weather discharges can accumulate in the sediments of receiving waters and may have adverse effects on the ecological system, especially on benthic organisms. here, a novel method is developed for evaluating the bioavailability of such hydrophobic organic pollutants by considering the digestive guts in deposit-feeding polychaetes. we compared the amount of polycyclic aromatic hydrocarbons (pahs) extracted by an organic solvent and by sodium dodecyl sul ... | 2005 | 15850200 |
| bioassays and selected chemical analysis of biocide-free antifouling coatings. | over the years several types of biocide-free antifouling paints have entered the market. the prohibition of biocidal antifouling paints in special areas of some european countries such as sweden, denmark and germany has favoured the introduction of these paints to the market. several types of biocide-free antifouling paints were subjected to bioassays and selected chemical analysis of leachate and incorporated substances. both non-eroding coatings (silicones, fibre coats, epoxies, polyurethane, ... | 2005 | 15878605 |
| oxidative degradation and toxicity reduction of trichloroethylene (tce) in water using tio2/solar light: comparative study of tio2 slurry and immobilized systems. | a solar-driven, photocatalyzed degradation system using tio2 slurry and immobilized systems was constructed and applied to the degradation of trichloroethylene (tce) contaminated water using tio2 with solar light. the experiments were carried out under constant weather conditions on a sunny day. solar photocatalytic treatment efficiency of the solar light/tio2 slurry system was compared with that of the solar light/tio2 immobilized system. the operation of the solar light/tio2 slurry and immobil ... | 2005 | 15887572 |
| layers of signaling in a bacterium-host association. | | 2005 | 15901681 |
| vibrio fischeri uses two quorum-sensing systems for the regulation of early and late colonization factors. | vibrio fischeri possesses two quorum-sensing systems, ain and lux, using acyl homoserine lactones as signaling molecules. we have demonstrated previously that the ain system activates luminescence gene expression at lower cell densities than those required for lux system activation and that both systems are essential for persistent colonization of the squid host, euprymna scolopes. here, we asked whether the relative contributions of the two systems are also important at different colonization s ... | 2005 | 15901683 |
| characteristics of endogenous flavin fluorescence of photobacterium leiognathi luciferase and vibrio fischeri nad(p)h:fmn-oxidoreductase. | the bioluminescent bacterial enzyme system nad(p)h:fmn-oxidoreductase-luciferase has been used as a test system for ecological monitoring. one of the modes to quench bioluminescence is the interaction of xenobiotics with the enzymes, which inhibit their activity. the use of endogenous flavin fluorescence for investigation of the interactions of non-fluorescent compounds with the bacterial luciferase from photobacterium leiognathi and nad(p)h:fmn-oxidoreductase from vibrio fischeri has been propo ... | 2005 | 15924327 |
| interactive toxic effects of heavy metals and humic acids on vibrio fischeri. | the effect of humic acids (has) on the toxicity of copper, zinc, and lead was investigated using the photobacterium vibrio fischeri (microtox test) as a test organism. the effects of has on metal toxicity were evaluated as functions of time and concentration in pure compound solutions. the toxicities of copper and lead were generally comparable, while the toxicity of zinc was lower than those of the other two metals. the toxicity of copper decreased with the addition of has, while the toxicity o ... | 2006 | 15939470 |
| efficacy and toxicity of self-polishing biocide-free antifouling paints. | the ban on harmful substances in antifouling paints requires the development of new antifouling strategies. alternatives should be as effective as conventional paints but of lower toxicity. in the present study two commercially available, self-polishing antifouling paints were examined in order to get information on their antifouling properties and toxicological potential. efficacy was shown in settlement assays with the marine barnacle species balanus amphitrite, however, efficacy was related t ... | 2005 | 15955603 |
| applicability of fenton and h2o2/uv reactions in the treatment of tannery wastewaters. | in this paper we evaluated the h2o2/uv and the fenton's oxidation processes for the treatment of tannery wastewater under different experimental conditions. efficiencies were judged by the amounts of organic substances degraded or eliminated under these treatment techniques. daphnia magna and vibrio fischeri were used to monitor toxicity. organic compounds contained in the untreated and treated tannery wastewater were determined and identified using substance specific techniques. gas chromatogra ... | 2005 | 15963803 |
| bacterial printing press that regenerates its ink: contact-printing bacteria using hydrogel stamps. | this paper describes the use of micropatterned agarose stamps prepared by molding against pdms masters to print patterns of bacteria on agar plates. topographically patterned agarose stamps were inked with suspensions of bacteria; these stamps generated patterns of bacteria with features as small as 200 microm over areas as large as 50 cm2. stamps with many small features (>200 microm) were used to study patterns of bacteria growing on media containing gradients of small molecules; stamps with l ... | 2005 | 15982051 |
| comparison of several toxicity tests applied to complex wastewaters and mussel biomarkers in receiving waters. | in this study, the complex wastewaters/effluents discharged to coastal regions of turkey and greece were sampled, and various toxicity tests were applied. the bioassays used included the assessment of the luminescence inhibition of the bacterium vibrio fisheri, the photosynthesis inhibition (14c uptake rate) and growth inhibition of the algal species phaeodactylum tricornutum, and the mortality of the crustacean artemia franciscana and rotifer brachionus plicatilis. additionally, "neutral red re ... | 2005 | 15991721 |
| effect of river water, sediment and time on the toxicity and bioavailability of molinate to the marine bacterium vibrio fischeri (microtox). | the toxicity and bioavailability of molinate to vibrio fischeri (microtox((r))) were determined in both laboratory and river water in the absence and presence of sediment after 0, 24, 48, 72 and 96-h exposure. the bioavailability of molinate, expressed as 5min ec50s (bioluminescence) and their fiducial limits calculated using initial measured concentrations, to v. fischeri in laboratory water in the absence and presence of sediment ranged from 1.8 (1.7-2.1) to 3.6 (3.5-3.7) mgl(-1) and 1.3 (1.2- ... | 2005 | 15992852 |
| bioluminescence-mediated stimulation of photoreactivation in bacteria. | although biochemistry and genetics of light emission by cells have been investigated in detail, a biological role for bacterial luminescence has remained obscure for a long time. it was proposed recently that luminescence may stimulate dna repair, but the specific mechanism of this phenomenon was not investigated. moreover, experiments showing decreased survival of uv-irradiated lux mutants relative to luminescent cells were performed previously using only one bacterial species, vibrio harveyi. ... | 2005 | 16040205 |
| bacterial luciferase activity and the intracellular redox pool in escherichia coli. | in this study, we analyzed the activity of a bacterial luciferase (luxab of vibrio fischeri) expressed under the control of a consensus-type promoter, lacuv5, in escherichia coli, and found that activity declines abruptly upon entry into the stationary growth phase. since this decline was reproducibly observed in strains cultured in various growth media, we refer to this phenomenon as adla (abrupt decline of luciferase activity) and define the time point when activity begins to decline as t (0). ... | 2005 | 16047200 |
| degradation mechanism and the toxicity assessment in tio2 photocatalysis and photolysis of parathion. | the photocatalytic degradation of methyl parathion was carried out using a circulating tio2/uv reactor. the experimental results showed that parathion was more effectively degraded in the photocatalytic condition than the photolysis and tio2-only condition. with photocatalysis, 10mg/l parathion was completely degraded within 60 min with a toc decrease exceeding 90% after 150 min. the main ionic byproducts during photocatalysis were measured. the nitrogen from parathion was recovered mainly as no ... | 2006 | 16051312 |
| evaluation of the toxicity of two soils from jales mine (portugal) using aquatic bioassays. | soil contamination can be one path for streams and groundwater contamination. as a complement of chemical analysis and total contaminants determination, bioassays can provide information on the bioavailable fraction of chemical compounds, focusing on the retention and habitat function of soils. in this study the evaluation of the toxicity of two soils from the abandoned jales mine (portugal) regarded both functions. the buffer capacity of soils was tested with bioassays carried out using the cla ... | 2005 | 16084560 |
| application of microbiotests and activated sludge respirometry for the evaluation of industrial wastewater toxicity. | | 2005 | 16094897 |
| ecotoxicological evaluation of diethanolamine using a battery of microbiotests. | in order to investigate the potential ecotoxicity of diethanolamine (dea), a battery of model systems was developed. dea is widely used as a chemical intermediate and as a surface-active agent in cosmetic formulations, pharmaceuticals and agricultural products. dea was studied using ecotoxicological model systems, representing four trophic levels, with several bioindicators evaluated at different exposure time periods. the battery included bioluminescence inhibition of the bacterium vibrio fisch ... | 2005 | 16095869 |
| a novel, conserved cluster of genes promotes symbiotic colonization and sigma-dependent biofilm formation by vibrio fischeri. | vibrio fischeri is the exclusive symbiont residing in the light organ of the squid euprymna scolopes. to understand the genetic requirements for this association, we searched a library of v. fischeri transposon insertion mutants for those that failed to colonize e. scolopes. we identified four mutants that exhibited severe defects in initiating colonization. sequence analysis revealed that the strains contained insertions in four different members of a cluster of 21 genes oriented in the same di ... | 2005 | 16102015 |
| characterization of pes213, a small mobilizable plasmid from vibrio fischeri. | most vibrio fischeri strains isolated from the euprymna scolopes light organ carry plasmids, often including both a large (>40kb) plasmid, and one or more small (<12kb) plasmids. the large plasmids share homology with pes100, which is the lone plasmid in v. fischeri type strain es114. pes100 appears to encode a conjugative system similar to that on plasmid r721. the small plasmids lack extensive similarity to pes100, but they almost always occur in cells that also harbor a large plasmid resembli ... | 2005 | 16122560 |
| effect of cadmium(ii), chromium(vi), and arsenic(v) on long-term viability- and growth-inhibition assays using vibrio fischeri marine bacteria. | as a complement to previous results obtained using the standard microtox acute-toxicity test, which is based on measuring the rapid decrease of bioluminescence (5 to 30 minutes of exposure) in vibrio fischeri bacteria in the presence of toxicants, the long-term effects of cd(ii), cr(vi), and as(v) were studied on growth rate and viability assays of the same bacteria adapted to longer-lasting cultures, i.e., 48 or 72 hours instead of 5 or 30 minutes. effects on viability or growth, as studied by ... | 2005 | 16132421 |
| chemical mixture toxicity testing with vibrio fischeri: combined effects of binary mixtures for ten soft electrophiles. | the toxicity of 30 binary combinations of 10 soft electrophiles was examined in microtox using dose-response curve (drc) analysis. chemicals from three groups of soft electrophiles-vinyl michael acceptors (i--react with a thiol group), dicarbonyl reactive agents (ii--react with a primary amine), and alpha-haloactivation compounds (iii--react with a thiol group)--were selected for testing to evaluate the relationship between molecular site of chemical action and combined toxic effect. for each co ... | 2006 | 16139365 |
| a test battery approach for the ecotoxicological evaluation of estuarine sediments. | the purpose of this study was to evaluate the overall sensitivity and applicability of a number of bioassays representing multiple trophic levels, for the preliminary ecotoxicological screening (tier i) of estuarine sediments. chemical analyses were conducted on sediments from all sampling sites to assist in interpreting results. as sediment is an inherently complex, heterogeneous geological matrix, the toxicity associated with different exposure routes (solid, porewater and elutriate phases) wa ... | 2005 | 16151609 |
| a novel and convenient self-drying system for bacterial preservation. | an effective microbial preservation technology for the long-term storage of viable prokaryotic cells is described. the method combines an almost instantaneous drying step with minimal stress to the cells during drying to maximize survival on rehydration. this is achieved by contact of a microlitre aliquot of a bacterial suspension with a novel, pre-dried activated charcoal cloth based matrix contained within a re-sealable system that can then be stored. the simple methodology completely circumve ... | 2005 | 16157210 |
| identification of toxicants from marine sediment using effect-directed analysis. | effect-directed analysis (eda) has been reported to be a powerful tool for the identification of the responsible toxicants in contaminated, hazardous environmental samples. the aim of this study was to investigate whether it also is possible to use currently available eda methodology to identify potentially relevant toxicants in samples that do not pose obvious problems. for this purpose, compounds extracted from a marine sediment sample from the west coast of sweden were separated into distinct ... | 2005 | 16161100 |
| humic acid toxicity in biologically treated soil contaminated with polycyclic aromatic hydrocarbons and pentachlorophenol. | contaminated soil from a land treatment unit at the libby groundwater superfund site in libby, mt, was amended with 14c pyrene and incubated for 396 days to promote biodegradation and the formation of soil-associated bound residues. humic and fulvic acids were extracted from the treated soil microcosms and analyzed for the presence of pyrene residues. biologic activity promoted 14c association with the fulvic acid fraction, but humic acid-associated 14c did not increase with biologic activity. t ... | 2005 | 16170453 |
| molecular characterization of autoinduction of bioluminescence in the microtox indicator strain vibrio fischeri atcc 49387. | repeated attempts to clone the luxi from vibrio fischeri atcc 49387 failed to produce a clone carrying a functional luxi. sequence data from the clones revealed the presence of a polymorphism when compared with previously published luxi sequences, prompting further characterization of bioluminescence regulation in v. fischeri atcc 49387. further investigation of v. fischeri atcc 49387 revealed that its luxi protein lacks detectable luxi activity due to the presence of a glutamine residue at posi ... | 2005 | 16175203 |
| toxicity and genotoxicity of surface water before and after various potabilization steps. | many studies have revealed the presence of compounds with genotoxic activity in drinking water by means of short-term mutagenicity tests. in this study, the influence of the different steps of surface water treatment on the mutagenicity of drinking water was evaluated. four different types of samples were collected: raw lake water, water after pre-disinfection with chlorine dioxide, water after filtration on granular activated carbon, and tap water. water extracts underwent a bacterial toxicity ... | 2005 | 16181804 |
| a review on advantages of implementing luminescence inhibition test (vibrio fischeri) for acute toxicity prediction of chemicals. | evaluation of biological effects using a rapid, sensitive and cost effective method can indicate specific information on toxicity/ecotoxicity. since assays based on animals, plants and algae are expensive, time consuming and require large sample volume, recent studies have emphasized the benefits of rapid, reproducible and cost effective bacterial assays for toxicity screening and assessment. this review focuses on a bacterial assay, i.e., vibrio fischeri bioluminescence inhibition assay, which ... | 2006 | 16188318 |
| assessment of the environmental hazard from municipal and industrial wastewater treatment sludge by employing chemical and biological methods. | chemical analyses and toxicity testing were employed in conjunction to evaluate the environmental hazard from the wasted sludge generated during the biological treatment of urban and industrial wastewaters. chemical analyses included determination of seven polychlorinated biphenyls (pcbs), 13 polycyclic aromatic hydrocarbons (pahs), total organic carbon (toc), and seven heavy metals (as, cd, cr, cu, pb, mn, and zn) in sludge and sludge leachates deriving from two standard leaching procedures: (a ... | 2005 | 16216634 |
| model study on the effect of 15 phenolic olive mill wastewater constituents on seed germination and vibrio fischeri metabolism. | olive mill wastewaters (omw) can be a severe problem when disposed of as untreated because of their high organic load, elevated concentration of polyphenols, and moderately low biodegradability. in the present study, the acute toxicity of 15 compounds with low molecular weight (<350 da), catechol, four benzoic acids, three phenylacetic acids, three phenylethanols, and four cinnamic acids, already isolated from the reverse osmosis in the fractionation of omw, was assessed on the marine bacterium ... | 2005 | 16218695 |
| microbial mariners. | | 2005 | 16231859 |
| effects of hydrogen sulfide to vibrio fischeri, scenedesmus vacuolatus, and daphnia magna. | the effects of hydrogen sulfide (h2s) were tested in three ecotoxicological tests in order to evaluate its confounding potential in assessment of pore water and groundwater toxicity. the luminescent bacteria vibrio fischeri, the water flea daphnia magna, and the microalgae scenedesmus vacuolatus often are part of a biotest battery. a new technique for the synthesis of hydrogen sulfide solutions of defined concentrations using an electrochemical generator instead of sodium sulfide solutions was u ... | 2005 | 16268165 |
| identifying components of the nf-kappab pathway in the beneficial euprymna scolopes-vibrio fischeri light organ symbiosis. | the toll/nf-kappab pathway is a common, evolutionarily conserved innate immune pathway that modulates the responses of animal cells to microbe-associated molecular patterns (mamps). because mamps have been implicated as critical elements in the signaling of symbiont-induced development, an expressed sequence tag library from the juvenile light organ of euprymna scolopes was used to identify members of the toll/nf-kappab pathway. full-length transcripts were identified by using 5' and 3' race pcr ... | 2005 | 16269728 |
| the luxr receptor: the sites of interaction with quorum-sensing signals and inhibitors. | the function of luxr homologues as quorum sensors is mediated by the binding of n-acyl-l-homoserine lactone (ahl) signal molecules to the n-terminal receptor site of the proteins. in this study, site-directed mutagenesis was carried out of the amino acid residues comprising the receptor site of luxr from vibrio fischeri, and the ability of the l42a, l42s, y62f, w66f, d79n, w94d, v109d, v109t and m135a luxr mutant proteins to activate green fluorescent protein expression from a p(luxi) promoter w ... | 2005 | 16272381 |
| comparative use of bacterial, algal and protozoan tests to study toxicity of azo- and anthraquinone dyes. | toxicity of two azo dyes (reactive orange 16 (ro16); congo red (cr)) and two anthraquinone dyes (remazol brilliant blue r (rbbr); disperse blue 3 (db3)) were compared using bacterium vibrio fischeri, microalga selenastrum capricornutum and ciliate tetrahymena pyriformis. the following respective endpoints were involved: acute toxicity measured as bacterial luminescence inhibition, algal growth inhibition, and the effects on the protozoa including viability, growth inhibition, grazing effect and ... | 2006 | 16297428 |
| spatial extent of degraded sediment quality in puget sound (washington state, u.s.a.) based upon measures of the sediment quality triad. | a survey was designed and conducted to determine the severity, spatial patterns, and spatial extent of degraded sediment quality in puget sound (washington state, usa). a weight of evidence compiled from results of chemical analyses, toxicity tests, and benthic infaunal analyses was used to classify the quality of sediments. sediment samples were collected from 300 locations within a 2363 km(2) area extending from the us/canada border to the inlets of southern puget sound and hood canal. degrade ... | 2005 | 16311828 |
| the sorting direct method for stochastic simulation of biochemical systems with varying reaction execution behavior. | a key to advancing the understanding of molecular biology in the post-genomic age is the development of accurate predictive models for genetic regulation, protein interaction, metabolism, and other biochemical processes. to facilitate model development, simulation algorithms must provide an accurate representation of the system, while performing the simulation in a reasonable amount of time. gillespie's stochastic simulation algorithm (ssa) accurately depicts spatially homogeneous models with sm ... | 2006 | 16321569 |
| characteristics of landfill leachates in central taiwan. | due to the complex nature of landfill leachates, the leachate treatment plants have difficulty to meet the current taiwan epa's effluent standards. three typical types of landfills, closed landfill a, mixed landfill b (disposal of msw with bottom ashes from msw incinerators) and direct msw landfill c, (disposal of msw only), are investigated in this research in order to have a better understanding of characteristics of leachates. factors investigated in this research include landfill age, ph, bo ... | 2006 | 16325888 |
| variation in, and causes of, toxicity of cigarette butts to a cladoceran and microtox. | cigarette butts are the most numerically frequent form of litter in the world. in australia alone, 24-32 billion cigarette butts are littered annually. despite this littering, few studies have been undertaken to explore the toxicity of cigarette butts in aquatic ecosystems. the acute toxicity of 19 filtered cigarette types to ceriodaphnia cf. dubia (48-hr ec50 (immobilization)) and vibrio fischeri (30-min ec50 (bioluminescence)) was determined using leachates from artificially smoked cigarette b ... | 2006 | 16328625 |
| environmentally controlled invasion of cancer cells by engineered bacteria. | bacteria can sense their environment, distinguish between cell types, and deliver proteins to eukaryotic cells. here, we engineer the interaction between bacteria and cancer cells to depend on heterologous environmental signals. we have characterized invasin from yersinia pseudotuburculosis as an output module that enables escherichia coli to invade cancer-derived cells, including hela, hepg2, and u2os lines. to environmentally restrict invasion, we placed this module under the control of hetero ... | 2006 | 16330045 |
| acute toxicity test of leachates from traditional and sustainable landfills using luminescent bacteria. | landfilling is a fundamental step in any waste management strategy, but it can constitute a hazard for the environment for a long time. the need to protect the environment from potential landfill emissions makes risk assessment a decision tool of extreme necessity. the heterogeneity of wastes and the complexity of physical, chemical and biological processes that occur in the body of a landfill need specific procedures in order to evaluate the groundwater risk for the environment. given the compl ... | 2006 | 16356704 |
| molecular communication through stochastic synchronization induced by extracellular fluctuations. | we model a synthetic gene regulatory network in a microbial cell, and investigate the effect of noises on cell-cell communication in a well-mixed multicellular system. a biologically plausible model is developed for cellular communication in an indirectly coupled multicellular system. without extracellular noises, all cells, in spite of interaction among them, behave irregularly due to independent intracellular noises. on the other hand, extracellular noises that are common to all cells can indu ... | 2005 | 16383875 |
| new rfp- and pes213-derived tools for analyzing symbiotic vibrio fischeri reveal patterns of infection and lux expression in situ. | genetically altered or tagged vibrio fischeri strains can be observed in association with their mutualistic host euprymna scolopes, providing powerful experimental approaches for studying this symbiosis. two limitations to such in situ analyses are the lack of suitably stable plasmids and the need for a fluorescent tag that can be used in tandem with green fluorescent protein (gfp). vectors previously used in v. fischeri contain the p15a replication origin; however, we found that this replicon i ... | 2006 | 16391121 |
| characterization of soluble microbial products (smp) derived from glucose and phenol in dual substrate activated sludge bioreactors. | soluble microbial products (smp) generated by activated sludge cultures receiving a mixed feed of phenol and glucose were characterized with respect to molecular weight (mw) distribution, octanol-water partition coefficient (k(ow)), and microtox toxicity. short-term batch reactor tests using 14c-labeled substrates were performed to collect smp derived from each substrate, while long-term tests were performed with smp accumulated over multiple feed cycles using fed-batch reactors receiving non-la ... | 2006 | 16402386 |
| photocatalytic decolorization and degradation of dye solutions and wastewaters in the presence of titanium dioxide. | in this study, the photocatalytic degradation of two commercial azo dyes in the presence of tio(2) suspensions as photocatalyst has been investigated. the degradation of the dyes follows a pseudo-first-order kinetics according to the langmuir-hinshelwood model. under the certain experimental conditions, in the presence of tio(2) p-25 decolorization is achieved within 100 min of illumination, while in the presence of tio(2) hombikat uv-100 complete color disappearance is accomplished in less than ... | 2006 | 16406296 |
| confocal microscopy of the light organ crypts in juvenile euprymna scolopes reveals their morphological complexity and dynamic function in symbiosis. | in the hours to days following hatching, the hawaiian bobtail squid, euprymna scolopes, obtains its light-emitting symbiont, vibrio fischeri, from the surrounding environment and propagates the bacteria in the epithelial crypts of a specialized light organ. three-dimensional analyses using confocal microscopy revealed that each of the three crypts on either side of the juvenile light organ is composed of four morphological regions. progressing from the lateral pore to the medial blind end of eac ... | 2006 | 16429442 |
| pah content, toxicity and genotoxicity of coastal marine sediments from the rovinj area, northern adriatic, croatia. | surface marine sediments collected from 8 sampling sites within the rovinj coastal area, northern adriatic, croatia, were used for determining priority pollutant polycyclic aromatic hydrocarbons (pahs) and toxic/genotoxic potential of sediment organic extracts. total pah concentrations ranged from 32 microg/kg (protected area) to 13.2 mg/kg dry weight (harbor) and showed clear differences between pristine, urban industrial and harbor areas. pahs distribution revealed their pyrogenic origin with ... | 2006 | 16439004 |
| characterization and optimization of two methods in the immobilization of 12 bioluminescent strains. | twelve recombinant bioluminescent bacteria have been immobilized within the wells of a 96-well plate using two different matrices--agar and sol-gel. all 12 strains were immobilized within individual wells of the plates and the sensitivity of the strains and the stability of the responses were determined for select chemicals. each strain was exposed to seven well-characterized chemicals over a wide range of concentrations to demonstrate their individual selectivity for specific toxicants. althoug ... | 2006 | 16439106 |
| biomonitoring of the genotoxic potential of aqueous extracts of soils and bottom ash resulting from municipal solid waste incineration, using the comet and micronucleus tests on amphibian (xenopus laevis) larvae and bacterial assays (mutatox and ames tests). | the management of contaminated soils and wastes is a matter of considerable human concern. the present study evaluates the genotoxic potential of aqueous extracts of two soils (leachates) and of bottom ash resulting from municipal solid waste incineration (mswiba percolate), using amphibian larvae (xenopus laevis). soil a was contaminated by residues of solvents and metals and soil b by polycyclic aromatic hydrocarbons and metals. mswiba was predominantly contaminated by metals. two genotoxic en ... | 2006 | 16442436 |
| effect of modified fenton's reaction on microbial activity and removal of pahs in creosote oil contaminated soil. | this study describes the removal of polycyclic aromatic hydrocarbons (pahs) from creosote oil contaminated soil by modified fenton's reaction in laboratory-scale column experiments and subsequent aerobic biodegradation of pahs by indigenous bacteria during incubation of the soil. the effect of hydrogen peroxide addition for 4 and 10 days and saturation of soil with h(2)o(2) on was studied. in both experiments the h(2)o(2) dosage was 0.4 g h(2)o(2)/g soil. in completely h(2)o(2)-saturated soil th ... | 2006 | 16456613 |
| comparison of different biological methods for the assessment of ecotoxicological risks. | to test the effects of heavy metals in river water, we compared the sensitivity of seven different biological test methods, using bacteria (vibrio fischeri), human fl cells, protozoans (paramecium spp.), nematodes (rhabditis oxycerca), aquatic plants (lemna minor), and fishes (leuciscus idus melanotus). as test substance we used a representative mixture of 3.0 microg/l as, 2.5 microg/l pb, 0.8 microg/l cd, 1.7 microg/l cr, 3.9 microg/l cu, 6.7 microg/l ni, 0.4 microg/l hg, and 23.0 microg/l zn, ... | 2006 | 16459144 |
| diethylaminoethyl-cellulose clean-up of a large volume naphthenic acid extract. | the athabasca oil sands of alberta, canada contain an estimated 174 billion barrels of bitumen. during oil sands refining processes, an extraction tailings mixture is produced that has been reported as toxic to aquatic organisms and is therefore collected in settling ponds on site. investigation into the toxicity of these tailings pond waters has identified naphthenic acids (nas) and their sodium salts as the major toxic components, and a multi-year study has been initiated to identify the princ ... | 2006 | 16469358 |
| coupling of 2,4,6-trinitrotoluene (tnt) metabolites onto humic monomers by a new laccase from trametes modesta. | during degradation of trinitrotoluene (tnt) by trametes modesta, addition of humic monomers prevented the accumulation of all major stable tnt metabolites (aminodinitrotoluenes [amdnt]) by at least 92% in the presence of 200 mm ferulic acid and guaiacol. acute toxicity tests with individual tnt metabolites and in t. modesta cultures supplemented with 200 microm tnt demonstrated that the tnt biodegradation process lead to less toxic metabolites. toxicity decreased in the order tnt>4-hadnt (4-hydr ... | 2006 | 16473393 |
| ecotoxicological effects of benzoxazinone allelochemicals and their metabolites on aquatic nontarget organisms. | before natural plant allelochemicals can be exploited as biological pesticides against weeds and for disease control, more than the effect on target organisms needs to be known. this study presents results of aquatic biotests using four organisms, namely, a water flea, a freshwater alga, a soil alga, and a luminescent bacterium. the tested substances were 10 benzoxazinone derivatives, 3 of them known to be wheat allelochemicals, benzoxazolin-2(3h)-one (boa), 6-methoxybenzoxazolin-2(3h)-one (mboa ... | 2006 | 16478223 |
| linking bacteriophage infection to quorum sensing signalling and bioluminescent bioreporter monitoring for direct detection of bacterial agents. | to incorporate into the lambda phage genome, a luxi-based acyl-homoserine lactone (ahl) synthase genetic construct and exploit the autoamplified power of quorum sensing to translate a phage infection event into a chemical signature detectable by a lux-based bioluminescent bioreporter, with focus towards facile detection of microbial pathogens. | 2006 | 16478488 |
| quorum sensing in vibrios: complexity for diversification. | n-acylhomoserine lactone-dependent quorum sensing was first discovered in two luminescent marine bacteria, vibrio fischeri and vibrio harveyi. the luxi/r system of v. fischeri is the paradigm of gram-negative quorum-sensing systems; however, it is not found in all vibrios. a more complex quorum-sensing regulation is found in v. harveyi. three parallel systems transmit signals via phosphorelays that converge onto one regulatory protein luxo. components of the three systems are found only in vibri ... | 2006 | 16487746 |
| crystallization and preliminary x-ray diffraction analysis of a cold-adapted catalase from vibrio salmonicida. | catalase (ec 1.11.1.6) catalyses the breakdown of hydrogen peroxide to water and molecular oxygen. recombinant vibrio salmonicida catalase (vsc) possesses typical cold-adapted features, with higher catalytic efficiency, lower thermal stability and a lower temperature optimum than its mesophilic counterpart from proteus mirabilis. crystals of vsc were produced by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. the crystals belong to the monoclinic space group p2(1) ... | 2006 | 16511268 |
| cyclo(phe-pro) modulates the expression of ompu in vibrio spp. | vibrio vulnificus was found to produce a chemical that induced the expression of vibrio fischeri lux genes. electron spray ionization-mass spectrometry and 1h nuclear magnetic resonance analyses indicated that the compound was cyclo(l-phe-l-pro) (cfp). the compound was produced at a maximal level when cell cultures reached the onset of stationary phase. sodium dodecyl sulfate-polyacrylamide gel analysis of the total proteins of v. vulnificus indicated that expression of ompu was enhanced by exog ... | 2006 | 16513751 |