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Sample records for vibrio fischeri daphnia

  1. Acute and Chronic Toxicity of Soluble Fractions of Industrial Solid Wastes on Daphnia magna and Vibrio fischeri

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    Letícia Flohr

    2012-01-01

    Full Text Available Industrial wastes may produce leachates that can contaminate the aquatic ecosystem. Toxicity testing in acute and chronic levels is essential to assess environmental risks from the soluble fractions of these wastes, since only chemical analysis may not be adequate to classify the hazard of an industrial waste. In this study, ten samples of solid wastes from textile, metal-mechanic, and pulp and paper industries were analyzed by acute and chronic toxicity tests with Daphnia magna and Vibrio fischeri. A metal-mechanic waste (sample MM3 induced the highest toxicity level to Daphnia magna(CE50,48 h=2.21%. A textile waste induced the highest toxicity level to Vibrio fischeri (sample TX2, CE50,30 min=12.08%. All samples of pulp and paper wastes, and a textile waste (sample TX2 induced chronic effects on reproduction, length, and longevity of Daphnia magna. These results could serve as an alert about the environmental risks of an inadequate waste classification method.

  2. Entry of Vibrio harveyi and Vibrio fischeri into the viable but nonculturable state.

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    Ramaiah, N; Ravel, J; Straube, W L; Hill, R T; Colwell, R R

    2002-01-01

    Physiological responses of marine luminous bacteria, Vibrio harveyi (ATCC 14216) and V. fischeri (UM1373) to nutrient-limited normal strength (35 ppt iso-osmolarity) and low (10 ppt hypo-osmolarity) salinity conditions were determined. Plate counts, direct viable counts, actively respiring cell counts, nucleoid-containing cell counts, and total counts were determined. Vibrio harveyi incubated at 22 degrees C in nutrient-limited artificial seawater (ASW) became nonculturable after approximately 62 and 45 d in microcosms of 35 ppt and 10 ppt ASW, respectively. In contrast, V. fischeri became nonculturable at approximately 55 and 31 d in similar microcosms. Recovery of both culturability and luminescence of cells in the viable but nonculturable state was achieved by addition of nutrient broth or nutrient broth supplemented with a carbon source, including luminescence-stimulating compounds. Temperature upshift from 22 degrees C to 30 degrees C or 37 degrees C did not result in recovery from nonculturability. The study confirms entry of V. harveyi and V. fischeri into the viable but nonculturable state under low-nutrient conditions and demonstrates nutrient-dependent resuscitation from this state. This study confirms loss of luminescence of V. harveyi and V. fischeri on entry into the viable but nonculturable state and suggests that enumeration of luminescent cells in water samples may be a rapid method to deduce the nutrient status of a water sample.

  3. Attenuation of Vibrio fischeri quorum sensing using rationally designed polymers.

    Science.gov (United States)

    Piletska, Elena V; Stavroulakis, Georgios; Karim, Kal; Whitcombe, Michael J; Chianella, Iva; Sharma, Anant; Eboigbodin, Kevin E; Robinson, Gary K; Piletsky, Sergey A

    2010-04-12

    A first attempt to attenuate the quorum sensing (QS) of a marine heterotroph microorganism, Vibrio fischeri , using signal molecule-sequestering polymers (SSPs) is presented. A set of rationally designed polymers with affinity toward a signal molecule of V. fischeri , N-(beta-ketocaproyl)-l-homoserine lactone (3-oxo-C6-AHL) was produced. It is reported that computationally designed polymers could sequester a signal molecule of V. fischeri and prevent QS-controlled phenotypes (in this case, bioluminescence) from being up-regulated. It was proven that the attenuation of bioluminescence of V. fischeri was due to sequestration of the signal molecule by specific polymers and not due to the toxicity of polymer or nonspecific depletion of nutrients. The ability to disrupt the bacterial communication using easy to synthesize and chemically inert polymers could provide a new concept for the development of pharmaceuticals and susceptible device coatings such as catheters.

  4. Aptamer-Based Paper Strip Sensor for Detecting Vibrio fischeri.

    Science.gov (United States)

    Shin, Woo-Ri; Sekhon, Simranjeet Singh; Rhee, Sung-Keun; Ko, Jung Ho; Ahn, Ji-Young; Min, Jiho; Kim, Yang-Hoon

    2018-05-14

    Aptamer-based paper strip sensor for detecting Vibrio fischeri was developed. Our method was based on the aptamer sandwich assay between whole live cells, V. fischeri and DNA aptamer probes. Following 9 rounds of Cell-SELEX and one of the negative-SELEX, V. fischeri Cell Aptamer (VFCA)-02 and -03 were isolated, with the former showing approximately 10-fold greater avidity (in the subnanomolar range) for the target cells when arrayed on a surface. The colorimetric response of a paper sensor based on VFCA-02 was linear in the range of 4 × 10 1 to 4 × 10 5 CFU/mL of target cell by using scanning reader. The linear regression correlation coefficient ( R 2 ) was 0.9809. This system shows promise for use in aptamer-conjugated gold nanoparticle probes in paper strip format for in-field detection of marine bioindicating bacteria.

  5. Squid-derived chitin oligosaccharides are a chemotactic signal during colonization by Vibrio fischeri.

    Science.gov (United States)

    Mandel, Mark J; Schaefer, Amy L; Brennan, Caitlin A; Heath-Heckman, Elizabeth A C; Deloney-Marino, Cindy R; McFall-Ngai, Margaret J; Ruby, Edward G

    2012-07-01

    Chitin, a polymer of N-acetylglucosamine (GlcNAc), is noted as the second most abundant biopolymer in nature. Chitin serves many functions for marine bacteria in the family Vibrionaceae ("vibrios"), in some instances providing a physical attachment site, inducing natural genetic competence, and serving as an attractant for chemotaxis. The marine luminous bacterium Vibrio fischeri is the specific symbiont in the light-emitting organ of the Hawaiian bobtail squid, Euprymna scolopes. The bacterium provides the squid with luminescence that the animal uses in an antipredatory defense, while the squid supports the symbiont's nutritional requirements. V. fischeri cells are harvested from seawater during each host generation, and V. fischeri is the only species that can complete this process in nature. Furthermore, chitin is located in squid hemocytes and plays a nutritional role in the symbiosis. We demonstrate here that chitin oligosaccharides produced by the squid host serve as a chemotactic signal for colonizing bacteria. V. fischeri uses the gradient of host chitin to enter the squid light organ duct and colonize the animal. We provide evidence that chitin serves a novel function in an animal-bacterial mutualism, as an animal-produced bacterium-attracting synomone.

  6. Polyphyly of non-bioluminescent Vibrio fischeri sharing a lux-locus deletion.

    Science.gov (United States)

    Wollenberg, M S; Preheim, S P; Polz, M F; Ruby, E G

    2012-03-01

    This study reports the first description and molecular characterization of naturally occurring, non-bioluminescent strains of Vibrio fischeri. These 'dark' V. fischeri strains remained non-bioluminescent even after treatment with both autoinducer and aldehyde, substrate additions that typically maximize light production in dim strains of luminous bacteria. Surprisingly, the entire lux locus (eight genes) was absent in over 97% of these dark V. fischeri strains. Although these strains were all collected from a Massachusetts (USA) estuary in 2007, phylogenetic reconstructions allowed us to reject the hypothesis that these newly described non-bioluminescent strains exhibit monophyly within the V. fischeri clade. These dark strains exhibited a competitive disadvantage against native bioluminescent strains when colonizing the light organ of the model V. fischeri host, the Hawaiian bobtail squid Euprymna scolopes. Significantly, we believe that the data collected in this study may suggest the first observation of a functional, parallel locus-deletion event among independent lineages of a non-pathogenic bacterial species. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  7. Population dynamics of Vibrio fischeri during infection of Euprymna scolopes.

    Science.gov (United States)

    McCann, Jessica; Stabb, Eric V; Millikan, Deborah S; Ruby, Edward G

    2003-10-01

    The luminous bacterium Vibrio fischeri colonizes a specialized light-emitting organ within its squid host, Euprymna scolopes. Newly hatched juvenile squid must acquire their symbiont from ambient seawater, where the bacteria are present at low concentrations. To understand the population dynamics of V. fischeri during colonization more fully, we used mini-Tn7 transposons to mark bacteria with antibiotic resistance so that the growth of their progeny could be monitored. When grown in culture, there was no detectable metabolic burden on V. fischeri cells carrying the transposon, which inserts in single copy in a specific intergenic region of the V. fischeri genome. Strains marked with mini-Tn7 also appeared to be equivalent to the wild type in their ability to infect and multiply within the host during coinoculation experiments. Studies of the early stages of colonization suggested that only a few bacteria became associated with symbiotic tissue when animals were exposed for a discrete period (3 h) to an inoculum of V. fischeri cells equivalent to natural population levels; nevertheless, all these hosts became infected. When three differentially marked strains of V. fischeri were coincubated with juvenile squid, the number of strains recovered from an individual symbiotic organ was directly dependent on the size of the inoculum. Further, these results indicated that, when exposed to low numbers of V. fischeri, the host may become colonized by only one or a few bacterial cells, suggesting that symbiotic infection is highly efficient.

  8. Depressed light emission by symbiotic Vibrio fischeri of the sepiolid squid Euprymna scolopes.

    OpenAIRE

    Boettcher, K J; Ruby, E G

    1990-01-01

    Bioluminescent marine bacteria of the species Vibrio fischeri are the specific light organ symbionts of the sepiolid squid Euprymna scolopes. Although they share morphological and physiological characteristics with other strains of V. fischeri, when cultured away from the light organ association the E. scolopes symbionts depress their maximal luminescence over 1,000-fold. The primary cause of this reduced luminescence is the underproduction by these bacteria of luciferase autoinducer, a molec...

  9. Construction and symbiotic competence of a luxA-deletion mutant of Vibrio fischeri.

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    Visick, K G; Ruby, E G

    1996-10-10

    Bioluminescence by the squid Euprymna scolopes requires colonization of its light organ by the symbiotic luminous bacterium Vibrio fischeri. Investigation of the genetic determinants underlying bacterial symbiotic competence in this system has necessitated the continuing establishment and application of molecular genetic techniques in V. fischeri. We developed a procedure for the introduction of plasmid DNA into V. fischeri by electroporation, and isolated a mutant strain that overcame the apparent restriction barrier between V. fischeri and Escherichia coli. Using the technique of electroporation in combination with that of gene replacement, we constructed a non-luminous strain of V. fischeri (delta luxA::erm). In addition, we used the transducing phage rp-1 for the first time to transfer a chromosomal antibiotic resistance marker to another strain of V. fischeri. The luxA mutant was able to colonize E. scolopes as quickly and to the same extent as wild type. This result suggested that, at least during the initial stages of colonization, luminescence per se is not an essential factor for the symbiotic infection.

  10. Competition between Vibrio fischeri strains during initiation and maintenance of a light organ symbiosis.

    OpenAIRE

    Lee, K H; Ruby, E G

    1994-01-01

    Colonization of the light-emitting organ of the Hawaiian squid Euprymna scolopes is initiated when the nascent organ of a newly hatched squid becomes inoculated with Vibrio fischeri cells present in the ambient seawater. Although they are induced for luminescence in the light organ, these symbiotic strains are characteristically non-visibly luminous (NVL) when grown in laboratory culture. The more typical visibly luminous (VL) type of V. fischeri co-occurs in Hawaiian seawater with these NVL ...

  11. A Study on the D. magna and V. fischeri Toxicity Relationship of Industrial Wastewater from Korea

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    Pyo, S.; Lee, S.; Chun Sang, H.; Park, T. J.; Kim, M. S.

    2015-12-01

    It is well known that high concentration of TDS (total dissolved solid) in industrial effluent gives rise to the toxicity to the Daphnia magna toxicity test. D. magna is vulnerable to relatively low TDS concentration showing the 24-hr EC50 of Salinity 0.6% (as the sea salt concentration). Recently, standard mandatory toxicity testing using Daphnia magna has been used to monitor industrial effluent toxicity according to Korea standard method (Acute Toxicity Test Method of the Daphnia magna Straus (Cladocera, Crustacea), ES 04704. 1a) under regulation. Since only one acute toxicity testing is applied in the present, we are trying to introduce microbial battery for more complete toxicity assessment. In this study, the acute toxicities between daphnids and microbes were compared. The results of D. magna and Vibrio fischeri toxicity test from 165 industrial wastewater effluents showed high positive correlation. In addition, the possibility of predicting daphnia toxicity from the bacterial toxicity data amounts to 92.6% if we consider salinity effect (>5ppt) together. From this study, we found that the V. fischeri toxicity test is a powerful battery tool to assess the industrial wastewater toxicity. Here, we suggest that luminescent bacteria toxicity test be useful not only for complete toxicity assessment which can't be obtained by daphnia toxicity testing only but also for the reduction cost, time, and labor in the Korean society. Keywords : D. magna, V. fischeri, Industrial waste water, battery test Acknowledgement This research was supported by a grant (15IFIP-B089908-02) from Plant Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government

  12. Recognition between symbiotic Vibrio fischeri and the haemocytes of Euprymna scolopes.

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    Nyholm, Spencer V; Stewart, Jennifer J; Ruby, Edward G; McFall-Ngai, Margaret J

    2009-02-01

    The light organ crypts of the squid Euprymna scolopes permit colonization exclusively by the luminous bacterium Vibrio fischeri. Because the crypt interior remains in contact with seawater, the squid must not only foster the specific symbiosis, but also continue to exclude other bacteria. Investigation of the role of the innate immune system in these processes revealed that macrophage-like haemocytes isolated from E. scolopes recognized and phagocytosed V. fischeri less than other closely related bacterial species common to the host's environment. Interestingly, phagocytes isolated from hosts that had been cured of their symbionts bound five times more V. fischeri cells than those from uncured hosts. No such change in the ability to bind other species of bacteria was observed, suggesting that the host adapts specifically to V. fischeri. Deletion of the gene encoding OmpU, the major outer membrane protein of V. fischeri, increased binding by haemocytes from uncured animals to the level observed for haemocytes from cured animals. Co-incubation with wild-type V. fischeri reduced this binding, suggesting that they produce a factor that complements the mutant's defect. Analyses of the phagocytosis of bound cells by fluorescence-activated cell sorting indicated that once binding to haemocytes had occurred, V. fischeri cells are phagocytosed as effectively as other bacteria. Thus, discrimination by this component of the squid immune system occurs at the level of haemocyte binding, and this response: (i) is modified by previous exposure to the symbiont and (ii) relies on outer membrane and/or secreted components of the symbionts. These data suggest that regulation of host haemocyte binding by the symbiont may be one of many factors that contribute to specificity in this association.

  13. Recognition between symbiotic Vibrio fischeri and the hemocytes of Euprymna scolopes

    Science.gov (United States)

    Nyholm, Spencer V.; Stewart, Jennifer J.; Ruby, Edward G.; McFall-Ngai, Margaret J.

    2008-01-01

    Summary The light-organ crypts of the squid Euprymna scolopes permit colonization exclusively by the luminous bacterium Vibrio fischeri. Because the crypt interior remains in contact with seawater, the squid must not only foster the specific symbiosis but also continue to exclude other bacteria. Investigation of the role of the innate immune system in these processes revealed that macrophage-like hemocytes isolated from E. scolopes recognized and phagocytosed V. fischeri less than other closely related bacterial species common to the host’s environment. Interestingly, phagocytes isolated from hosts that had been cured of their symbionts bound five-times more V. fischeri cells than those from uncured hosts. No such change in the ability to bind other species of bacteria was observed, suggesting that the host adapts specifically to V. fischeri. Deletion of the gene encoding OmpU, the major outer membrane protein of V. fischeri, increased binding by hemocytes from uncured animals to the level observed for hemocytes from cured animals. Co-incubation with wild-type V. fischeri reduced this binding, suggesting they produce a factor that complements the mutant’s defect. Analyses of the phagocytosis of bound cells by fluorescence-activated cell sorting (FACS) indicated that, once binding to hemocytes had occurred, V. fischeri cells are phagocytosed as effectively as other bacteria. Thus, discrimination by this component of the squid immune system occurs at the level of hemocyte binding, and this response: (i) is modified by previous exposure to the symbiont and, (ii) relies on outer membrane and/or secreted components of the symbionts. These data suggest that regulation of host hemocyte binding by the symbiont may be one of many factors that contribute to specificity in this association. PMID:19196278

  14. Detection and quantification of Vibrio fischeri autoinducer from symbiotic squid light organs.

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    Boettcher, K J; Ruby, E G

    1995-02-01

    Vibrio fischeri is the specific light organ symbiont of the sepiolid squid species Euprymna scolopes and Euprymna morsei. Both species of squid are luminescent by virtue of their bacterial symbionts, but the natural symbionts of E. scolopes do not produce visible luminescence in laboratory culture. The primary cause of this depressed luminescence by E. scolopes symbionts in culture was found to be the production of relatively low levels of V. fischeri autoinducer, a positive transcriptional coregulator of the lux regulon, identified as N-(3-oxohexanoyl) homoserine lactone. Concentrations of autoinducer activity produced by these symbionts in culture were quantified and found to be at least 10-fold lower than those produced by E. morsei isolates (which are visibly luminous outside the association) and perhaps 10,000-fold lower than those of the brightest V. fischeri strains. Despite the differences in their symbiont strains, the intact light organs of the two species of squid contained comparable amounts of extractable autoinducer activity (between 100 and 200 pg per adult animal). The chromatographic behavior of this autoinducer activity on reverse-phase high-performance liquid chromatography was consistent with its presumptive identification as V. fischeri autoinducer. Within the 5-microliter volume of the epithelial core of the light organ in which the symbiotic V. fischeri strains are housed, these amounts would result in an effective autoinducer concentration of at least 100 nM. Because these levels are over 40-fold higher than the concentration needed for the induction of luminescence of bacteria in culture, we conclude that the inherent degree of autoinducer production by strains of V. fischeri may not influence their effectiveness as light organ symbionts. Furthermore, this study provides the first direct evidence that the phenomenon of cell density-dependent autoinduction, discovered and described first for laboratory cultures of V. fischeri but believed to

  15. Population Structure of Vibrio fischeri within the Light Organs of Euprymna scolopes Squid from Two Oahu (Hawaii) Populations▿ †

    OpenAIRE

    Wollenberg, M. S.; Ruby, E. G.

    2008-01-01

    We resolved the intraspecific diversity of Vibrio fischeri, the bioluminescent symbiont of the Hawaiian sepiolid squid Euprymna scolopes, at two previously unexplored morphological and geographical scales. These scales ranged from submillimeter regions within the host light organ to the several kilometers encompassing two host populations around Oahu. To facilitate this effort, we employed both novel and standard genetic and phenotypic assays of light-organ symbiont populations. A V. fischeri...

  16. Depressed light emission by symbiotic Vibrio fischeri of the sepiolid squid Euprymna scolopes.

    Science.gov (United States)

    Boettcher, K J; Ruby, E G

    1990-07-01

    Bioluminescent marine bacteria of the species Vibrio fischeri are the specific light organ symbionts of the sepiolid squid Euprymna scolopes. Although they share morphological and physiological characteristics with other strains of V. fischeri, when cultured away from the light organ association the E. scolopes symbionts depress their maximal luminescence over 1,000-fold. The primary cause of this reduced luminescence is the underproduction by these bacteria of luciferase autoinducer, a molecule involved in the positive transcriptional regulation of the V. fischeri lux operon. Such an absence of visible light production outside of the symbiotic association has not been previously reported among light organ symbionts of this or any other species of luminous bacteria. Levels of luminescence approaching those of the E. scolopes bacteria in the intact association can be restored by the addition of exogenous autoinducer to bacteria in laboratory culture and are affected by the presence of cyclic AMP. We conclude that some condition(s) specific to the internal environment of the light organ is necessary for maximal autoinduction of luminescence in the symbionts of this squid-bacterial association.

  17. Symbiotic Role of the Viable but Nonculturable State of Vibrio fischeri in Hawaiian Coastal Seawater.

    Science.gov (United States)

    Lee, K; Ruby, E G

    1995-01-01

    To achieve functional bioluminescence, the developing light organ of newly hatched juveniles of the Hawaiian squid Euprymna scolopes must become colonized by luminous, symbiosis-competent Vibrio fischeri present in the ambient seawater. This benign infection occurs rapidly in animals placed in seawater from the host's natural habitat. Therefore, it was surprising that colony hybridization studies with a V. fischeri-specific luxA gene probe indicated the presence of only about 2 CFU of V. fischeri per ml of this infective seawater. To examine this paradox, we estimated the total concentration of V. fischeri cells present in seawater from the host's habitat in two additional ways. In the first approach, the total bacterial assemblage in samples of seawater was collected on polycarbonate membrane filters and used as a source of both a crude cell lysate and purified DNA. These preparations were then assayed by quantitative DNA-DNA hybridization with the luxA gene probe. The results suggested the presence of between 200 and 400 cells of V. fischeri per ml of natural seawater, a concentration more than 100 times that revealed by colony hybridization. In the second approach, we amplified V. fischeri-specific luxA sequences from microliter volumes of natural seawater by PCR. Most-probable-number analyses of the frequency of positive PCR results from cell lysates in these small volumes gave an estimate of the concentration of V. fischeri luxA gene targets of between 130 and 1,680 copies per ml. From these measurements, we conclude that in their natural seawater environment, the majority of V. fischeri cells become nonculturable while remaining viable and symbiotically infective. Experimental studies indicated that V. fischeri cells suspended in natural Hawaiian seawater enter such a state within a few days.

  18. Toxicity assessment of ionic liquids with Vibrio fischeri: an alternative fully automated methodology.

    Science.gov (United States)

    Costa, Susana P F; Pinto, Paula C A G; Lapa, Rui A S; Saraiva, M Lúcia M F S

    2015-03-02

    A fully automated Vibrio fischeri methodology based on sequential injection analysis (SIA) has been developed. The methodology was based on the aspiration of 75 μL of bacteria and 50 μL of inhibitor followed by measurement of the luminescence of bacteria. The assays were conducted for contact times of 5, 15, and 30 min, by means of three mixing chambers that ensured adequate mixing conditions. The optimized methodology provided a precise control of the reaction conditions which is an asset for the analysis of a large number of samples. The developed methodology was applied to the evaluation of the impact of a set of ionic liquids (ILs) on V. fischeri and the results were compared with those provided by a conventional assay kit (Biotox(®)). The collected data evidenced the influence of different cation head groups and anion moieties on the toxicity of ILs. Generally, aromatic cations and fluorine-containing anions displayed higher impact on V. fischeri, evidenced by lower EC50. The proposed methodology was validated through statistical analysis which demonstrated a strong positive correlation (P>0.98) between assays. It is expected that the automated methodology can be tested for more classes of compounds and used as alternative to microplate based V. fischeri assay kits. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Iron control of the Vibrio fischeri luminescence system in Escherichia coli.

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    Dunlap, P V

    1992-01-01

    Iron influences luminescence in Vibrio fischeri; cultures iron-restricted for growth rate induce luminescence at a lower optical density (OD) than faster growing, iron-replete cultures. An iron restriction effect analogous to that in V. fischeri (slower growth, induction of luminescence at a lower OD) was established using Escherichia coli tonB and tonB+ strains transformed with recombinant plasmids containing the V. fischeri lux genes (luxR luxICDABEG) and grown in the presence and absence of the iron chelator ethylenediamine-di(o-hydroxylphenyl acetic acid) (EDDHA). This permitted the mechanism of iron control of luminescence to be examined. A fur mutant and its parent strain containing the intact lux genes exhibited no difference in the OD at induction of luminescence. Therefore, an iron-binding repressor protein apparently is not involved in iron control of luminescence. Furthermore, in the tonB and in tonB+ strains containing lux plasmids with Mu dI(lacZ) fusions in luxR, levels of beta-galactosidase activity (expression from the luxR promoter) and luciferase activity (expression from the luxICDABEG promoter) both increased by a similar amount (8-9 fold each for tonB, 2-3 fold each for tonB+) in the presence of EDDHA. Similar results were obtained with the luxR gene present on a complementing plasmid. The previously identified regulatory factors that control the lux system (autoinducer-LuxR protein, cyclic AMP-cAMP receptor protein) differentially control expression from the luxR and luxICDABEG promoters, increasing expression from one while decreasing expression from the other. Consequently, these results suggest that the effect of iron on the V. fischeri luminescence system is indirect.

  20. Detection of the Light Organ Symbiont, Vibrio fischeri, in Hawaiian Seawater by Using lux Gene Probes.

    Science.gov (United States)

    Lee, K H; Ruby, E G

    1992-03-01

    Symbiotic bacteria that inhabit the light-emitting organ of the Hawaiian squid Euprymna scolopes are distinctive from typical Vibrio fischeri organisms in that they are not visibly luminous when grown in laboratory culture. Therefore, the abundance of these bacteria in seawater samples cannot be estimated simply by identifying them among luminous colonies that arise on nutrient agar plates. Instead, we have used luxR and polymerase chain reaction generated luxA gene probes to identify both luminous and non-visibly luminous V. fischeri colonies by DNA-DNA hybridization. The probes were specific, hybridizing at least 50 to 100 times more strongly to immobilized DNAs from V. fischeri strains than to those of pure cultures of other related species. Thus, even non-visibly luminous V. fischeri colonies could be identified among colonies obtained from natural seawater samples by their probe-positive reaction. Bacteria in seawater samples, obtained either within or distant from squid habitats, were collected on membrane filters and incubated until colonies appeared. The filters were then observed for visibly luminous V. fischeri colonies and hybridized with the lux gene probes to determine the number of total V. fischeri colonies (both luminous and non-visibly luminous). We detected no significant differences in the abundance of luminous V. fischeri CFU in any of the water samples observed (fischeri (up to 900 CFU/100 ml) were found only in seawater collected from within the natural habitats of the squids. A number of criteria were used to confirm that these probe-positive strains were indistinguishable from symbiotic V. fischeri. Therefore, the luxA and luxR gene probes were species specific and gave a reliable estimate of the number of culturable V. fischeri colonies in natural water samples.

  1. Detection of the Light Organ Symbiont, Vibrio fischeri, in Hawaiian Seawater by Using lux Gene Probes †

    Science.gov (United States)

    Lee, Kyu-Ho; Ruby, Edward G.

    1992-01-01

    Symbiotic bacteria that inhabit the light-emitting organ of the Hawaiian squid Euprymna scolopes are distinctive from typical Vibrio fischeri organisms in that they are not visibly luminous when grown in laboratory culture. Therefore, the abundance of these bacteria in seawater samples cannot be estimated simply by identifying them among luminous colonies that arise on nutrient agar plates. Instead, we have used luxR and polymerase chain reaction generated luxA gene probes to identify both luminous and non-visibly luminous V. fischeri colonies by DNA-DNA hybridization. The probes were specific, hybridizing at least 50 to 100 times more strongly to immobilized DNAs from V. fischeri strains than to those of pure cultures of other related species. Thus, even non-visibly luminous V. fischeri colonies could be identified among colonies obtained from natural seawater samples by their probe-positive reaction. Bacteria in seawater samples, obtained either within or distant from squid habitats, were collected on membrane filters and incubated until colonies appeared. The filters were then observed for visibly luminous V. fischeri colonies and hybridized with the lux gene probes to determine the number of total V. fischeri colonies (both luminous and non-visibly luminous). We detected no significant differences in the abundance of luminous V. fischeri CFU in any of the water samples observed (≤1 to 3 CFU/100 ml). However, probe-positive colonies of V. fischeri (up to 900 CFU/100 ml) were found only in seawater collected from within the natural habitats of the squids. A number of criteria were used to confirm that these probe-positive strains were indistinguishable from symbiotic V. fischeri. Therefore, the luxA and luxR gene probes were species specific and gave a reliable estimate of the number of culturable V. fischeri colonies in natural water samples. Images PMID:16348678

  2. Influence of Select Antibiotics on Vibrio fischeri and Desmodesmus subspicatus at μg L-1 Concentrations.

    Science.gov (United States)

    de Vasconcelos, E C; Dalke, C R; de Oliveira, C M R

    2017-07-01

    The presence of pharmaceuticals in the aquatic environment is a contemporary reality and it is necessary to understand more about the effects of this presence on organisms. The purpose of this work was to assess the ecotoxicity of antibiotics metronidazole, nitrofurantoin, trimethoprim, and sulphamethoxazole (single and mixture) in Vibrio fischeri and Desmodesmus subspicatus at μg L -1 concentrations. The evaluation of the toxic effect of the antibiotics on V. fischeri and D. subspicatus was based on fluorescence and bioluminescence tests, respectively, using nominal concentrations. When tested individually, the four antibiotics gave rise to a toxic effect on the evaluated organisms. Sulphamethoxazole caused a higher toxic effect on V. fischeri and D. subspicatus from 7.81 to 500 μg L -1 . Trimethoprim and sulphamethoxazole showed hormesis for the concentrations, which ranged from 7.81 to 62.5 μg L -1 . The mixture of antibiotics induced a toxic effect on the V. fischeri and D. subspicatus organisms (from 0.03 to 1 μg L -1 concentrations) than when the antibiotics were evaluated individually. These results were significant since water quality problems are widespread all over the word, and emerging pollutants such as antibiotics have been detected in the aquatic environment in very low concentrations.

  3. Lessons from a cooperative, bacterial-animal association: the Vibrio fischeri-Euprymna scolopes light organ symbiosis.

    Science.gov (United States)

    Ruby, E G

    1996-01-01

    Although the study of microbe-host interactions has been traditionally dominated by an interest in pathogenic associations, there is an increasing awareness of the importance of cooperative symbiotic interactions in the biology of many bacteria and their animal and plant hosts. This review examines a model system for the study of such symbioses, the light organ association between the bobtail squid Euprymna scolopes and the marine luminous bacterium Vibrio fischeri. Specifically, the initiation, establishment, and persistence of the benign bacterial infection of the juvenile host light organ are described, as are efforts to understand the mechanisms underlying this specific colonization program. Using molecular genetic techniques, mutant strains of V. fischeri have been constructed that are defective at specific stages of the development of the association. Some of the lessons that these mutants have begun to teach us about the complex and long-term nature of this cooperative venture are summarized.

  4. Noise and crosstalk in two quorum-sensing inputs of Vibrio fischeri

    Directory of Open Access Journals (Sweden)

    Weiss Joel T

    2011-09-01

    Full Text Available Abstract Background One of the puzzles in bacterial quorum sensing is understanding how an organism integrates the information gained from multiple input signals. The marine bacterium Vibrio fischeri regulates its bioluminescence through a quorum sensing mechanism that receives input from three pheromone signals, including two acyl homoserine lactone (HSL signals. While the role of the 3-oxo-C6 homoserine lactone (3OC6HSL signal in activating the lux genes has been extensively studied and modeled, the role of the C8 homoserine lactone (C8HSL is less obvious, as it can either activate luminescence or block its activation. It remains unclear how crosstalk between C8HSL and 3OC6HSL affects the information that the bacterium obtains through quorum sensing. Results We have used microfluidic methods to measure the response of individual V.fischeri cells to combinations of C8HSL and 3OC6HSL. By measuring the fluorescence of individual V.fischeri cells containing a chromosomal gfp-reporter for the lux genes, we study how combinations of exogenous HSLs affect both the population average and the cell-to-cell variability of lux activation levels. At the level of a population average, the crosstalk between the C8HSL and 3OC6HSL inputs is well-described by a competitive inhibition model. At the level of individual cells, the heterogeneity in the lux response depends only on the average degree of activation, so that the noise in the output is not reduced by the presence of the second HSL signal. Overall we find that the mutual information between the signal inputs and the lux output is less than one bit. A nonlinear correlation between fluorescence and bioluminescence outputs from lux leads to different noise properties for these reporters. Conclusions The lux genes in V.fischeri do not appear to distinguish between the two HSL inputs, and even with two signal inputs the regulation of lux is extremely noisy. Hence the role of crosstalk from the C8HSL input

  5. Physical and functional maps of the luminescence gene cluster in an autoinducer-deficient Vibrio fischeri strain isolated from a squid light organ.

    Science.gov (United States)

    Gray, K M; Greenberg, E P

    1992-07-01

    Vibrio fischeri ES114 is an isolate representing the specific bacterial light organ symbiont of the squid Euprymna scolopes. An interesting feature of this strain of V. fischeri is that it is visibly luminous within the light organ of the squid host but is nonluminous when grown under standard laboratory conditions. Luminescence can be restored in laboratory culture, however, by the addition of autoinducer, a species-specific inducer of the V. fischeri luminescence (lux) genes. Most other isolates of V. fischeri produce autoinducer in sufficient quantities to induce luminescence in laboratory culture. We have cloned an 8.8-kb DNA fragment from V. fischeri ES114 that encodes all of the functions necessary for luminescence in Escherichia coli in the absence of exogenous autoinducer. This DNA contains both of the recognized V. fischeri lux regulatory genes, one of which (luxI) directs E. coli to synthesize autoinducer. The organization of the individual lux genes within this DNA fragment appears to be the same as that in the other strains of V. fischeri studied; the restriction map of the V. fischeri ES114 lux DNA has diverged substantially, however, from the largely conserved maps of V. fischeri MJ1 and ATCC 7744. Although E. coli containing the V. fischeri ES114 lux DNA synthesizes considerable amounts of autoinducer, V. fischeri ES114 synthesizes autoinducer only in small amounts, even when transcription of the lux genes, including luxI, is activated by the addition of exogenous autoinducer. Nonetheless, transconjugants of V. fischeri ES114 that contain multicopy plasmids bearing the ES114 lux genes synthesize sufficient autoinducer to induce luminescence. These results suggest that V. fischeri ES11r does not lack a functional luxl, nor is it deficient in the ability to synthesize metabolic precursors for autoinducer synthesis.

  6. Detection of the Light Organ Symbiont, Vibrio fischeri, in Hawaiian Seawater by Using lux Gene Probes †

    OpenAIRE

    Lee, Kyu-Ho; Ruby, Edward G.

    1992-01-01

    Symbiotic bacteria that inhabit the light-emitting organ of the Hawaiian squid Euprymna scolopes are distinctive from typical Vibrio fischeri organisms in that they are not visibly luminous when grown in laboratory culture. Therefore, the abundance of these bacteria in seawater samples cannot be estimated simply by identifying them among luminous colonies that arise on nutrient agar plates. Instead, we have used luxR and polymerase chain reaction generated luxA gene probes to identify both lu...

  7. Anaerobic respiratory growth of Vibrio harveyi, Vibrio fischeri and Photobacterium leiognathi with trimethylamine N-oxide, nitrate and fumarate: ecological implications.

    Science.gov (United States)

    Proctor, L M; Gunsalus, R P

    2000-08-01

    Two symbiotic species, Photobacterium leiognathi and Vibrio fischeri, and one non-symbiotic species, Vibrio harveyi, of the Vibrionaceae were tested for their ability to grow by anaerobic respiration on various electron acceptors, including trimethylamine N-oxide (TMAO) and dimethylsulphoxide (DMSO), compounds common in the marine environment. Each species was able to grow anaerobically with TMAO, nitrate or fumarate, but not with DMSO, as an electron acceptor. Cell growth under microaerophilic growth conditions resulted in elevated levels of TMAO reductase, nitrate reductase and fumarate reductase activity in each strain, whereas growth in the presence of the respective substrate for each enzyme further elevated enzyme activity. TMAO reductase specific activity was the highest of all the reductases. Interestingly, the bacteria-colonized light organs from the two squids, Euprymna scolopes and Euprymna morsei, and the light organ of the ponyfish, Leiognathus equus, also had high levels of TMAO reductase enzyme activity, in contrast to non-symbiotic tissues. The ability of these bacterial symbionts to support cell growth by respiration with TMAO may conceivably eliminate the competition for oxygen needed for both bioluminescence and metabolism.

  8. Competition between Vibrio fischeri strains during initiation and maintenance of a light organ symbiosis.

    Science.gov (United States)

    Lee, K H; Ruby, E G

    1994-04-01

    Colonization of the light-emitting organ of the Hawaiian squid Euprymna scolopes is initiated when the nascent organ of a newly hatched squid becomes inoculated with Vibrio fischeri cells present in the ambient seawater. Although they are induced for luminescence in the light organ, these symbiotic strains are characteristically non-visibly luminous (NVL) when grown in laboratory culture. The more typical visibly luminous (VL) type of V. fischeri co-occurs in Hawaiian seawater with these NVL strains; thus, two phenotypically distinct groups of this species potentially have access to the symbiotic niche, yet only the NVL ones are found there. In laboratory inoculation experiments, VL strains, when presented in pure culture, showed the same capability for colonizing the light organ as NVL strains. However, in experiments with mixed cultures composed of both VL and NVL strains, the VL ones were unable to compete with the NVL ones and did not persist within the light organ as the symbiosis became established. In addition, NVL strains entered light organs that had already been colonized by VL strains and displaced them. The mechanism underlying the symbiotic competitiveness exhibited by NVL strains remains unknown; however, it does not appear to be due to a higher potential for siderophore activity. While a difference in luminescence phenotype between VL and NVL strains in culture is not likely to be significant in the symbiosis, it has helped identify two distinct groups of V. fischeri that express different colonization capabilities in the squid light organ. This competitive difference provides a useful indication of important traits in light organ colonization.

  9. Interactions between bicarbonate, potassium, and magnesium, and sulfur-dependent induction of luminescence in Vibrio fischeri.

    Science.gov (United States)

    Tabei, Yosuke; Era, Mariko; Ogawa, Akane; Morita, Hiroshi

    2012-06-01

    In spite of its central importance in research efforts, the relationship between seawater compounds and bacterial luminescence has not previously been investigated in detail. Thus, in this study, we investigated the effect of cations (Na(+) , K(+) , NH(4) (+) , Mg(2+) , and Ca(2+) ) and anions (Cl(-) , HCO(3) (-) , CO(3) (2-) , and NO(3) (-) ) on the induction of both inorganic (sulfate, sulfite, and thiosulfate) and organic (L-cysteine and L-cystine) sulfur-dependent luminescence in Vibrio fischeri. We found that HCO(3) (-) (bicarbonate) and CO(3) (2-) (carbonate), in the form of various compounds, had a stimulatory effect on sulfur-dependent luminescence. The luminescence induced by bicarbonate was further promoted by the addition of magnesium. Potassium also increased sulfur-dependent luminescence when sulfate or thiosulfate was supplied as the sole sulfur source, but not when sulfite, L-cysteine, or L-cystine was supplied. The positive effect of potassium was accelerated by the addition of magnesium and/or calcium. Furthermore, the additional supply of magnesium improved the induction of sulfite- or L-cysteine-dependent luminescence, but not the l-cystine-dependent type. These results suggest that sulfur-dependent luminescence of V. fischeri under nutrient-starved conditions is mainly controlled by bicarbonate, carbonate, and potassium. In addition, our results indicate that an additional supply of magnesium is effective for increasing V. fischeri luminescence. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Growth and flagellation of Vibrio fischeri during initiation of the sepiolid squid light organ symbiosis.

    Science.gov (United States)

    Ruby, E G; Asato, L M

    1993-01-01

    A pure culture of the luminous bacterium Vibrio fischeri is maintained in the light-emitting organ of the sepiolid squid Euprymna scolopes. When the juvenile squid emerges from its egg it is symbiont-free and, because bioluminescence is part of an anti-predatory behavior, therefore must obtain a bacterial inoculum from the surrounding environment. We document here the kinetics of the process by which newly hatched juvenile squids become infected by symbiosis-competent V. fischeri. When placed in seawater containing as few as 240 colony-forming-units (CFU) per ml, the juvenile became detectably bioluminescent within a few hours. Colonization of the nascent light organ was initiated with as few as 1 to 10 bacteria, which rapidly began to grow at an exponential rate until they reached a population size of approximately 10(5) cells by 12 h after the initial infection. Subsequently, the number of bacteria in the established symbiosis was maintained essentially constant by a combination of both a > 20-fold reduction in bacterial growth rate, and an expulsion of excess bacteria into the surrounding seawater. While V. fischeri cells are normally flagellated and motile, these bacteria did not elaborate these appendages once the symbiosis was established; however, they quickly began to synthesize flagella when they were removed from the light organ environment. Thus, two important biological characteristics, growth rate and flagellation, were modulated during establishment of the association, perhaps as part of a coordinated series of symbiotic responses.

  11. Alterations in the proteome of the Euprymna scolopes light organ in response to symbiotic Vibrio fischeri.

    Science.gov (United States)

    Doino Lemus, J; McFall-Ngai, M J

    2000-09-01

    During the onset of the cooperative association between the Hawaiian sepiolid squid Euprymna scolopes and the marine luminous bacterium Vibrio fischeri, the anatomy and morphology of the host's symbiotic organ undergo dramatic changes that require interaction with the bacteria. This morphogenetic process involves an array of tissues, including those in direct contact with, as well as those remote from, the symbiotic bacteria. The bacteria induce the developmental program soon after colonization of the organ, although complete morphogenesis requires 96 h. In this study, to determine critical time points, we examined the biochemistry underlying bacterium-induced host development using two-dimensional polyacrylamide gel electrophoresis. Specifically, V. fischeri-induced changes in the soluble proteome of the symbiotic organ during the first 96 h of symbiosis were identified by comparing the protein profiles of symbiont-colonized and uncolonized organs. Both symbiosis-related changes and age-related changes were analyzed to determine what proportion of the differences in the proteomes was the result of specific responses to interaction with bacteria. Although no differences were detected over the first 24 h, numerous symbiosis-related changes became apparent at 48 and 96 h and were more abundant than age-related changes. In addition, many age-related protein changes occurred 48 h sooner in symbiotic animals, suggesting that the interaction of squid tissue with V. fischeri cells accelerates certain developmental processes of the symbiotic organ. These data suggest that V. fischeri-induced modifications in host tissues that occur in the first 24 h of the symbiosis are independent of marked alterations in the patterns of abundant proteins but that the full 4-day morphogenetic program requires significant alteration of the host soluble proteome.

  12. Population structure of Vibrio fischeri within the light organs of Euprymna scolopes squid from Two Oahu (Hawaii) populations.

    Science.gov (United States)

    Wollenberg, M S; Ruby, E G

    2009-01-01

    We resolved the intraspecific diversity of Vibrio fischeri, the bioluminescent symbiont of the Hawaiian sepiolid squid Euprymna scolopes, at two previously unexplored morphological and geographical scales. These scales ranged from submillimeter regions within the host light organ to the several kilometers encompassing two host populations around Oahu. To facilitate this effort, we employed both novel and standard genetic and phenotypic assays of light-organ symbiont populations. A V. fischeri-specific fingerprinting method and five phenotypic assays were used to gauge the genetic richness of V. fischeri populations; these methods confirmed that the symbiont population present in each adult host's light organ is polyclonal. Upon statistical analysis of these genetic and phenotypic population data, we concluded that the characteristics of symbiotic populations were more similar within individual host populations than between the two distinct Oahu populations of E. scolopes, providing evidence that local geographic symbiont population structure exists. Finally, to better understand the genesis of symbiont diversity within host light organs, the process of symbiosis initiation in newly hatched juvenile squid was examined both experimentally and by mathematical modeling. We concluded that, after the juvenile hatches, only one or two cells of V. fischeri enter each of six internal epithelium-lined crypts present in the developing light organ. We hypothesize that the expansion of different, crypt-segregated, clonal populations creates the polyclonal adult light-organ population structure observed in this study. The stability of the luminous-bacterium-sepiolid squid mutualism in the presence of a polyclonal symbiont population structure is discussed in the context of contemporary evolutionary theory.

  13. Development of thresholds of excess toxicity for environmental species and their application to identification of modes of acute toxic action.

    Science.gov (United States)

    Li, Jin J; Zhang, Xu J; Yang, Yi; Huang, Tao; Li, Chao; Su, Limin; Zhao, Yuan H; Cronin, Mark T D

    2018-03-01

    The acute toxicity of organic pollutants to fish, Daphnia magna, Tetrahymena pyriformis, and Vibrio fischeri was investigated. The results indicated that the Toxicity Ratio (TR) threshold of log TR =1, which has been based on the distribution of toxicity data to fish, can also be used to discriminate reactive or specifically acting compounds from baseline narcotics for Daphnia magna and Vibrio fischeri. A log TR=0.84 is proposed for Tetrahymena pyriformis following investigation of the relationships between the species sensitivity and the absolute averaged residuals (AAR) between the predicted baseline toxicity and the experimental toxicity. Less inert compounds exhibit relatively higher toxicity to the lower species (Tetrahymena pyriformis and Vibrio fischeri) than the higher species (fish and Daphnia magna). A greater number of less inert compounds with log TR greater than the thresholds was observed for Tetrahymena pyriformis and Vibrio fischeri. This may be attributed to the hydrophilic compounds which may pass more easily through cell membranes than the skin or exoskeleton of organisms and have higher bioconcentration factors in the lower species, leading to higher toxicity. Most of classes of chemical associated with excess toxicity to one species also exhibited excess toxicity to other species, however, a few classes with excess toxicity to one species exhibiting narcotic toxicity to other species and thus may have different MOAs between species. Some ionizable compounds have log TR much lower than one because of the over-estimated log K OW . The factors that influence the toxicity ratio calculated from baseline level are discussed in this paper. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Purification and crystallization of Vibrio fischeri CcdB and its complexes with fragments of gyrase and CcdA

    International Nuclear Information System (INIS)

    De Jonge, Natalie; Buts, Lieven; Vangelooven, Joris; Mine, Natacha; Van Melderen, Laurence; Wyns, Lode; Loris, Remy

    2007-01-01

    A CcdB homologue from V. fischeri was overexpressed in E. coli and purified. The free protein was crystallized, as were its complexes with fragments of E. coli and V. fischeri gyrase and with the F-plasmid CcdA C-terminal domain. The ccd toxin–antitoxin module from the Escherichia coli F plasmid has a homologue on the Vibrio fischeri integron. The homologue of the toxin (CcdB Vfi ) was crystallized in two different crystal forms. The first form belongs to space group I23 or I2 1 3, with unit-cell parameter a = 84.5 Å, and diffracts to 1.5 Å resolution. The second crystal form belongs to space group C2, with unit-cell parameters a = 58.5, b = 43.6, c = 37.5 Å, β = 110.0°, and diffracts to 1.7 Å resolution. The complex of CcdB Vfi with the GyrA14 Vfi fragment of V. fischeri gyrase crystallizes in space group P2 1 2 1 2 1 , with unit-cell parameters a = 53.5, b = 94.6, c = 58.1 Å, and diffracts to 2.2 Å resolution. The corresponding mixed complex with E. coli GyrA14 Ec crystallizes in space group C2, with unit-cell parameters a = 130.1, b = 90.8, c = 58.1 Å, β = 102.6°, and diffracts to 1.95 Å. Finally, a complex between CcdB Vfi and part of the F-plasmid antitoxin CcdA F crystallizes in space group P2 1 2 1 2 1 , with unit-cell parameters a = 46.9, b = 62.6, c = 82.0 Å, and diffracts to 1.9 Å resolution

  15. Population Structure of Vibrio fischeri within the Light Organs of Euprymna scolopes Squid from Two Oahu (Hawaii) Populations▿ †

    Science.gov (United States)

    Wollenberg, M. S.; Ruby, E. G.

    2009-01-01

    We resolved the intraspecific diversity of Vibrio fischeri, the bioluminescent symbiont of the Hawaiian sepiolid squid Euprymna scolopes, at two previously unexplored morphological and geographical scales. These scales ranged from submillimeter regions within the host light organ to the several kilometers encompassing two host populations around Oahu. To facilitate this effort, we employed both novel and standard genetic and phenotypic assays of light-organ symbiont populations. A V. fischeri-specific fingerprinting method and five phenotypic assays were used to gauge the genetic richness of V. fischeri populations; these methods confirmed that the symbiont population present in each adult host's light organ is polyclonal. Upon statistical analysis of these genetic and phenotypic population data, we concluded that the characteristics of symbiotic populations were more similar within individual host populations than between the two distinct Oahu populations of E. scolopes, providing evidence that local geographic symbiont population structure exists. Finally, to better understand the genesis of symbiont diversity within host light organs, the process of symbiosis initiation in newly hatched juvenile squid was examined both experimentally and by mathematical modeling. We concluded that, after the juvenile hatches, only one or two cells of V. fischeri enter each of six internal epithelium-lined crypts present in the developing light organ. We hypothesize that the expansion of different, crypt-segregated, clonal populations creates the polyclonal adult light-organ population structure observed in this study. The stability of the luminous-bacterium-sepiolid squid mutualism in the presence of a polyclonal symbiont population structure is discussed in the context of contemporary evolutionary theory. PMID:18997024

  16. Purification and crystallization of Vibrio fischeri CcdB and its complexes with fragments of gyrase and CcdA

    Energy Technology Data Exchange (ETDEWEB)

    De Jonge, Natalie, E-mail: ndejonge@vub.ac.be; Buts, Lieven; Vangelooven, Joris [Department of Molecular and Cellular Interactions, VIB, Pleinlaan 2, 1050 Brussels (Belgium); Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium); Mine, Natacha; Van Melderen, Laurence [Laboratoire de Génétique des Procaryotes, Institut de Biologie et de Médecine, Université Libre de Bruxelles, Gosselies (Belgium); Wyns, Lode; Loris, Remy [Department of Molecular and Cellular Interactions, VIB, Pleinlaan 2, 1050 Brussels (Belgium); Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium)

    2007-04-01

    A CcdB homologue from V. fischeri was overexpressed in E. coli and purified. The free protein was crystallized, as were its complexes with fragments of E. coli and V. fischeri gyrase and with the F-plasmid CcdA C-terminal domain. The ccd toxin–antitoxin module from the Escherichia coli F plasmid has a homologue on the Vibrio fischeri integron. The homologue of the toxin (CcdB{sub Vfi}) was crystallized in two different crystal forms. The first form belongs to space group I23 or I2{sub 1}3, with unit-cell parameter a = 84.5 Å, and diffracts to 1.5 Å resolution. The second crystal form belongs to space group C2, with unit-cell parameters a = 58.5, b = 43.6, c = 37.5 Å, β = 110.0°, and diffracts to 1.7 Å resolution. The complex of CcdB{sub Vfi} with the GyrA14{sub Vfi} fragment of V. fischeri gyrase crystallizes in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 53.5, b = 94.6, c = 58.1 Å, and diffracts to 2.2 Å resolution. The corresponding mixed complex with E. coli GyrA14{sub Ec} crystallizes in space group C2, with unit-cell parameters a = 130.1, b = 90.8, c = 58.1 Å, β = 102.6°, and diffracts to 1.95 Å. Finally, a complex between CcdB{sub Vfi} and part of the F-plasmid antitoxin CcdA{sub F} crystallizes in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 46.9, b = 62.6, c = 82.0 Å, and diffracts to 1.9 Å resolution.

  17. Aposymbiotic culture of the sepiolid squid Euprymna scolopes: role of the symbiotic bacterium Vibrio fischeri in host animal growth, development, and light organ morphogenesis.

    Science.gov (United States)

    Claes, M F; Dunlap, P V

    2000-02-15

    The sepiolid squid Euprymna scolopes forms a bioluminescent mutualism with the luminous bacterium Vibrio fischeri, harboring V. fischeri cells in a complex ventral light organ and using the bacterial light in predator avoidance. To characterize the contribution of V. fischeri to the growth and development of E. scolopes and to define the long-term effects of bacterial colonization on light organ morphogenesis, we developed a mariculture system for the culture of E. scolopes from hatching to adulthood, employing artificial seawater, lighting that mimicked that of the natural environment, and provision of prey sized to match the developmental stage of E. scolopes. Animals colonized by V. fischeri and animals cultured in the absence of V. fischeri (aposymbiotic) grew and survived equally well, developed similarly, and reached sexual maturity at a similar age. Development of the light organ accessory tissues (lens, reflectors, and ink sac) was similar in colonized and aposymbiotic animals with no obvious morphometric or histological differences. Colonization by V. fischeri influenced regression of the ciliated epithelial appendages (CEAs), the long-term growth of the light organ epithelial tubules, and the appearance of the cells composing the ciliated ducts, which exhibit characteristics of secretory tissue. In certain cases, aposymbiotic animals retained the CEAs in a partially regressed state and remained competent to initiate symbiosis with V. fischeri into adulthood. In other cases, the CEAs regressed fully in aposymbiotic animals, and these animals were not colonizable. The results demonstrate that V. fischeri is not required for normal growth and development of the animal or for development of the accessory light organ tissues and that morphogenesis of only those tissues coming in contact with the bacteria (CEAs, ciliated ducts, and light organ epithelium) is altered by bacterial colonization of the light organ. Therefore, V. fischeri apparently makes no major

  18. Mechanism for iron control of the Vibrio fischeri luminescence system: involvement of cyclic AMP and cyclic AMP receptor protein and modulation of DNA level.

    Science.gov (United States)

    Dunlap, P V

    1992-07-01

    Iron controls luminescence in Vibrio fischeri by an indirect but undefined mechanism. To gain insight into that mechanism, the involvement of cyclic AMP (cAMP) and cAMP receptor protein (CRP) and of modulation of DNA levels in iron control of luminescence were examined in V. fischeri and in Escherichia coli containing the cloned V. fischeri lux genes on plasmids. For V. fischeri and E. coli adenylate cyclase (cya) and CRP (crp) mutants containing intact lux genes (luxR luxICDABEG), presence of the iron chelator ethylenediamine-di(o-hydroxyphenyl acetic acid) (EDDHA) increased expression of the luminescence system like in the parent strains only in the cya mutants in the presence of added cAMP. In the E. coli strains containing a plasmid with a Mu dl(lacZ) fusion in luxR, levels of beta-galactosidase activity (expression from the luxR promoter) and luciferase activity (expression from the lux operon promoter) were both 2-3-fold higher in the presence of EDDHA in the parent strain, and for the mutants this response to EDDHA was observed only in the cya mutant in the presence of added cAMP. Therefore, cAMP and CRP are required for the iron restriction effect on luminescence, and their involvement in iron control apparently is distinct from the known differential control of transcription from the luxR and luxICDABEG promoters by cAMP-CRP. Furthermore, plasmid and chromosomal DNA levels were higher in E. coli and V. fischeri in the presence of EDDHA. The higher DNA levels correlated with an increase in expression of chromosomally encoded beta-galactosidase in E. coli and with a higher level of autoinducer in cultures of V. fischeri. These results implicate cAMP-CRP and modulation of DNA levels in the mechanism of iron control of the V. fischeri luminescence system.

  19. Induction of a gradual, reversible morphogenesis of its host's epithelial brush border by Vibrio fischeri.

    Science.gov (United States)

    Lamarcq, L H; McFall-Ngai, M J

    1998-02-01

    Bacteria exert a variety of influences on the morphology and physiology of animal cells whether they are pathogens or cooperative partners. The association between the luminous bacterium Vibrio fischeri and the sepiolid squid Euprymna scolopes provides an experimental model for the study of the influence of extracellular bacteria on the development of host epithelia. In this study, we analyzed bacterium-induced changes in the brush borders of the light organ crypt epithelia during the initial hours following colonization of this tissue. Transmission electron microscopy of the brush border morphology in colonized and uncolonized hosts revealed that the bacteria effect a fourfold increase in microvillar density over the first 4 days of the association. Estimates of the proportions of bacterial cells in contact with host microvilli showed that the intimacy of the bacterial cells with animal cell surfaces increases significantly during this time. Antibiotic curing of the organ following colonization showed that sustained interaction with bacteria is essential for the retention of the induced morphological changes. Bacteria that are defective in either light production or colonization efficiency produced changes similar to those by the parent strain. Conventional fluorescence and confocal scanning laser microscopy revealed that the brush border is supported by abundant filamentous actin. However, in situ hybridization with beta-actin probes did not show marked bacterium-induced increases in beta-actin gene expression. These experiments demonstrate that the E. scolopes-V. fischeri system is a viable model for the experimental study of bacterium-induced changes in host brush border morphology.

  20. Temperature affects species distribution in symbiotic populations of Vibrio spp.

    Science.gov (United States)

    Nishiguchi, M K

    2000-08-01

    The genus Sepiola (Cephalopoda: Sepiolidae) contains 10 known species that occur in the Mediterranean Sea today. All Sepiola species have a light organ that contains at least one of two species of luminous bacteria, Vibrio fischeri and Vibrio logei. The two Vibrio species coexist in at least four Sepiola species (S. affinis, S. intermedia, S. ligulata, and S. robusta), and their concentrations in the light organ depend on changes in certain abiotic factors, including temperature. Strains of V. fischeri grew faster in vitro and in Sepiola juveniles when they were incubated at 26 degrees C. In contrast, strains of V. logei grew faster at 18 degrees C in culture and in Sepiola juveniles. When aposymbiotic S. affinis or S. ligulata juveniles were inoculated with one Vibrio species, all strains of V. fischeri and V. logei were capable of infecting both squid species at the optimum growth temperatures, regardless of the squid host from which the bacteria were initially isolated. However, when two different strains of V. fischeri and V. logei were placed in direct competition with each other at either 18 or 26 degrees C, strains of V. fischeri were present in sepiolid light organs in greater concentrations at 26 degrees C, whereas strains of V. logei were present in greater concentrations at 18 degrees C. In addition to the competition experiments, the ratios of the two bacterial species in adult Sepiola specimens caught throughout the season at various depths differed, and these differences were correlated with the temperature in the surrounding environment. My findings contribute additional data concerning the ecological and environmental factors that affect host-symbiont recognition and may provide insight into the evolution of animal-bacterium specificity.

  1. Bioluminescent Vibrio fischeri assays in the assessment of seasonal and spatial patterns in toxicity of contaminated river sediments

    Directory of Open Access Journals (Sweden)

    Sergio Jarque

    2016-11-01

    Full Text Available Several bacteria-based assays, notably Vibrio fischeri luminescence assays, are often used as environmental monitoring tool for toxicity in sediments that may serve as both sinks and secondary source of contamination in aquatic ecosystems. In this study, we used 30-s kinetic bioassays based on V. fischeri to evaluate the toxicity associated to sediments from five localities with different contamination inputs (Morava River and its tributary Drevnice River in the south-eastern part of the Czech Republic. Toxicity assessed as half maximal inhibitory concentration (IC50 over the course of a year-long sampling was compared in bottom sediments and freshly trapped particulate material. Standard approach based on testing of aqueous elutriates was compared with toxicity of whole sediments (contact suspension toxicity. Bottom sediments showed lower toxicity compared to freshly trapped suspended materials in all cases. On the other hand, standardized elutriates induced generally weaker effects than suspended sediments likely due to losses during the extraction process. Toxicity generally increased during winter reaching maximum peaks in early spring months in all five sites. Total organic carbon (TOC was found to be highly correlated with toxic effects. Toxicity from sites with direct industrial and agricultural water inputs also correlated with concentrations of metals, polycyclic aromatic hydrocarbons (PAHs and polychlorinated biphenyls (PCBs. Single time point sampling followed by the extraction and testing of elutriates, do not truly reflect the spatial and temporal variability in natural sediments and may lead to underestimation of ecotoxic risks.

  2. A Spectral-SAR Model for the Anionic-Cationic Interaction in Ionic Liquids: Application to Vibrio fischeri Ecotoxicity

    Directory of Open Access Journals (Sweden)

    Vasile Ostafe

    2007-08-01

    Full Text Available Within the recently launched the spectral-structure activity relationship (S-SARanalysis, the vectorial anionic-cationic model of a generic ionic liquid is proposed, alongwith the associated algebraic correlation factor in terms of the measured and predictedactivity norms. The reliability of the present scheme is tested by assessing the Hanschfactors, i.e. lipophylicity, polarizability and total energy, to predict the ecotoxicityendpoints of wide types of ionic liquids with ammonium, pyridinium, phosphonium,choline and imidazolium cations on the aquatic bacteria Vibrio fischeri. The results, whileconfirming the cationic dominant influence when only lipophylicity is considered,demonstrate that the anionic effect dominates all other more specific interactions. It wasalso proved that the S-SAR vectorial model predicts considerably higher activity for theionic liquids than for its anionic and cationic subsystems separately, in all consideredcases. Moreover, through applying the least norm-correlation path principle, the completetoxicological hierarchies are presented, unfolding the ecological rules of combined cationicand anionic influences in ionic liquid toxicity.

  3. Characterizing the host and symbiont proteomes in the association between the Bobtail squid, Euprymna scolopes, and the bacterium, Vibrio fischeri.

    Directory of Open Access Journals (Sweden)

    Tyler R Schleicher

    Full Text Available The beneficial symbiosis between the Hawaiian bobtail squid, Euprymna scolopes, and the bioluminescent bacterium, Vibrio fischeri, provides a unique opportunity to study host/microbe interactions within a natural microenvironment. Colonization of the squid light organ by V. fischeri begins a lifelong association with a regulated daily rhythm. Each morning the host expels an exudate from the light organ consisting of 95% of the symbiont population in addition to host hemocytes and shed epithelial cells. We analyzed the host and symbiont proteomes of adult squid exudate and surrounding light organ epithelial tissue using 1D- and 2D-polyacrylamide gel electrophoresis and multidimensional protein identification technology (MudPIT in an effort to understand the contribution of both partners to the maintenance of this association. These proteomic analyses putatively identified 1581 unique proteins, 870 proteins originating from the symbiont and 711 from the host. Identified host proteins indicate a role of the innate immune system and reactive oxygen species (ROS in regulating the symbiosis. Symbiont proteins detected enhance our understanding of the role of quorum sensing, two-component signaling, motility, and detoxification of ROS and reactive nitrogen species (RNS inside the light organ. This study offers the first proteomic analysis of the symbiotic microenvironment of the adult light organ and provides the identification of proteins important to the regulation of this beneficial association.

  4. Bright luminescence of Vibrio fischeri aconitase mutants reveals a connection between citrate and the Gac/Csr regulatory system.

    Science.gov (United States)

    Septer, Alecia N; Bose, Jeffrey L; Lipzen, Anna; Martin, Joel; Whistler, Cheryl; Stabb, Eric V

    2015-01-01

    The Gac/Csr regulatory system is conserved throughout the γ-proteobacteria and controls key pathways in central carbon metabolism, quorum sensing, biofilm formation and virulence in important plant and animal pathogens. Here we show that elevated intracellular citrate levels in a Vibrio fischeri aconitase mutant correlate with activation of the Gac/Csr cascade and induction of bright luminescence. Spontaneous or directed mutations in the gene that encodes citrate synthase reversed the bright luminescence of aconitase mutants, eliminated their citrate accumulation and reversed their elevated expression of CsrB. Our data elucidate a correlative link between central metabolic and regulatory pathways, and they suggest that the Gac system senses a blockage at the aconitase step of the tricarboxylic acid cycle, either through elevated citrate levels or a secondary metabolic effect of citrate accumulation, and responds by modulating carbon flow and various functions associated with host colonization, including bioluminescence. © 2014 John Wiley & Sons Ltd.

  5. Automated evaluation of pharmaceutically active ionic liquids’ (eco)toxicity through the inhibition of human carboxylesterase and Vibrio fischeri

    International Nuclear Information System (INIS)

    Costa, Susana P.F.; Justina, Vanessa D.; Bica, Katharina; Vasiloiu, Maria; Pinto, Paula C.A.G.; Saraiva, M. Lúcia M.F.S.

    2014-01-01

    Highlights: • IL-APIs toxicity on humans and aquatic environment was evaluated by inhibition assays. • The inhibition assays were implemented through automated screening bioassays. • Automation of bioassays enabled a rigorous control of the reaction conditions. • EC 50 obtained provide vital information on IL-APIs safety and potential use as drugs. -- Abstract: The toxicity of 16 pharmaceutical active ionic liquids (IL-APIs) was evaluated by automated approaches based on sequential injection analysis (SIA). The implemented bioassays were centered on the inhibition of human carboxylesterase 2 and Vibrio fischeri, in the presence of the tested compounds. The inhibitory effects were quantified by calculating the inhibitor concentration required to cause 50% of inhibition (EC 50 ). The EC 50 values demonstrated that the cetylpyridinium group was one of the most toxic cations and that the imidazolium group was the less toxic. The obtained results provide important information about the safety of the studied IL-APIs and their possible use as pharmaceutical drugs. The developed automated SIA methodologies are robust screening bioassays, and can be used as a generic tools to identify the (eco)toxicity of the structural elements of ILs, contributing to a sustainable development of drugs

  6. Comparison of Toxicities to Vibrio fischeri and Fish Based on Discrimination of Excess Toxicity from Baseline Level

    Science.gov (United States)

    Wang, Xiao H.; Yu, Yang; Huang, Tao; Qin, Wei C.; Su, Li M.; Zhao, Yuan H.

    2016-01-01

    Investigations on the relationship of toxicities between species play an important role in the understanding of toxic mechanisms to environmental organisms. In this paper, the toxicity data of 949 chemicals to fish and 1470 chemicals to V. fischeri were used to investigate the modes of action (MOAs) between species. The results show that although there is a positive interspecies correlation, the relationship is poor. Analysis on the excess toxicity calculated from toxic ratios (TR) shows that many chemicals have close toxicities and share the same MOAs between the two species. Linear relationships between the toxicities and octanol/water partition coefficient (log KOW) for baseline and less inert compounds indicate that the internal critical concentrations (CBRs) approach a constant both to fish and V. fischeri for neutral hydrophobic compounds. These compounds share the same toxic mechanisms and bio-uptake processes between species. On the other hand, some hydrophilic compounds exhibit different toxic effects with greatly different log TR values between V. fischeri and fish species. These hydrophilic compounds were identified as reactive MOAs to V. fischeri, but not to fish. The interspecies correlation is improved by adding a hydrophobic descriptor into the correlation equation. This indicates that the differences in the toxic ratios between fish and V. fischeri for these hydrophilic compounds can be partly attributed to the differences of bioconcentration between the two species, rather than the differences of reactivity with the target macromolecules. These hydrophilic compounds may more easily pass through the cell membrane of V. fischeri than the gill and skin of fish, react with the target macromolecules and exhibit excess toxicity. The compounds with log KOW > 7 exhibiting very low toxicity (log TR toxicity and MOAs. PMID:26901437

  7. Reduction of acute toxicity of the pharmaceutical fluoxetine (Prozac) submitted to ionizing radiation to Vibrio fischeri

    International Nuclear Information System (INIS)

    Santos, Dymes R.A.; Garcia, Vanessa S.G.; Vilarrubia, Anna C.S.; Borrely, Sueli I.

    2011-01-01

    The constant use of pharmaceutical drugs by great part of the population and its continuous input into the environment creates a growing need of investigating its presence, behavior and the effects on aquatic biota, as well as new ways to treat wastewater containing such substances. The fluoxetine hydrochloride (FH) present in the drug Prozac is an active ingredient used in the treatment of depressive and anxiety disorders. Generally, these compounds enter the aquatic environment by sewage collectors systems after undergoing prior treatment in sewage treatment plants (STPs) or without any treatment. This study focused on evaluating the reduction of acute toxicity of the pharmaceutical FH, under its manipulated formula, for the marine bacterium Vibrio fischeri. It was also evaluated the acute toxicity of the aqueous solution containing the FH after its exposition to ionizing radiation from industrial electron accelerator. It was performed acute toxicity tests lasting 15 minutes, where the average EC (50) of the non-irradiated CF water solution was approximately 0.68 mg L-1. While the CF water solution irradiated with 1 kGy, 2.5 kGy, 7.5 kGy and 10 kGy, presented an average EC(50) 1.63 mg.L -1 , 2.34 mg.L -1 , 2.35 mg.L -1 and 1.80 mg.L -1 , respectively, showing a notable reduction of the acute toxicity for this organism. (author)

  8. Assessment of heavy metals bioavailability and toxicity toward Vibrio fischeri in sediment of the Huelva estuary.

    Science.gov (United States)

    Rosado, Daniel; Usero, José; Morillo, José

    2016-06-01

    Relationship between toxicity and bioavailable metals in sediments from the Huelva estuary and its littoral of influence was analyzed. Toxicity was assessed with Microtox® bioassay using a marine luminescent bacterium: Vibrio fischeri. Bioavailable metals were considered as both, acid extractable fraction of BCR procedure and the sum of exchangeable and bound to carbonates fractions of Tessier sequential extraction. A bioavailable metals index was calculated to integrate results in a single figure. Toxicity and bioavailable metals showed a similar pattern. Higher levels were found in the estuary than in the littoral (140 TU/g). In Huelva estuary, highest levels were found in the Tinto estuary (5725 TU/g), followed by the Odiel estuary (5100 TU/g) and the Padre Santo Canal (2500 TU/g). Results in this area were well over than those in nearby estuaries. Furthermore, they are similar to or even higher than those in other polluted sediments around the world. Bioavailable metal index showed a stronger correlation with acid extractable fraction of BCR (R(2) = 0.704) than that for the sum of exchangeable and bound to carbonates fractions of Tessier (R(2) = 0.661). These results suggest that bioavailable metals are an important source of sediment toxicity in the Huelva estuary and its littoral of influence, an area with one of the highest mortality risks of Spain. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Reduction of acute toxicity of the pharmaceutical fluoxetine (Prozac) submitted to ionizing radiation to Vibrio fischeri

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Dymes R.A.; Garcia, Vanessa S.G.; Vilarrubia, Anna C.S.; Borrely, Sueli I., E-mail: vanessagarcia@usp.br, E-mail: sborrely@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The constant use of pharmaceutical drugs by great part of the population and its continuous input into the environment creates a growing need of investigating its presence, behavior and the effects on aquatic biota, as well as new ways to treat wastewater containing such substances. The fluoxetine hydrochloride (FH) present in the drug Prozac is an active ingredient used in the treatment of depressive and anxiety disorders. Generally, these compounds enter the aquatic environment by sewage collectors systems after undergoing prior treatment in sewage treatment plants (STPs) or without any treatment. This study focused on evaluating the reduction of acute toxicity of the pharmaceutical FH, under its manipulated formula, for the marine bacterium Vibrio fischeri. It was also evaluated the acute toxicity of the aqueous solution containing the FH after its exposition to ionizing radiation from industrial electron accelerator. It was performed acute toxicity tests lasting 15 minutes, where the average EC (50) of the non-irradiated CF water solution was approximately 0.68 mg L-1. While the CF water solution irradiated with 1 kGy, 2.5 kGy, 7.5 kGy and 10 kGy, presented an average EC(50) 1.63 mg.L{sup -1}, 2.34 mg.L{sup -1}, 2.35 mg.L{sup -1} and 1.80 mg.L{sup -1}, respectively, showing a notable reduction of the acute toxicity for this organism. (author)

  10. A new niche for Vibrio logei, the predominant light organ symbiont of squids in the genus Sepiola.

    Science.gov (United States)

    Fidopiastis, P M; von Boletzky, S; Ruby, E G

    1998-01-01

    Two genera of sepiolid squids--Euprymna, found primarily in shallow, coastal waters of Hawaii and the Western Pacific, and Sepiola, the deeper-, colder-water-dwelling Mediterranean and Atlantic squids--are known to recruit luminous bacteria into light organ symbioses. The light organ symbiont of Euprymna spp. is Vibrio fischeri, but until now, the light organ symbionts of Sepiola spp. have remained inadequately identified. We used a combination of molecular and physiological characteristics to reveal that the light organs of Sepiola affinis and Sepiola robusta contain a mixed population of Vibrio logei and V. fischeri, with V. logei comprising between 63 and 100% of the bacteria in the light organs that we analyzed. V. logei had not previously been known to exist in such symbioses. In addition, this is the first report of two different species of luminous bacteria co-occurring within a single light organ. The luminescence of these symbiotic V. logei strains, as well as that of other isolates of V. logei tested, is reduced when they are grown at temperatures above 20 degrees C, partly due to a limitation in the synthesis of aliphatic aldehyde, a substrate of the luminescence reaction. In contrast, the luminescence of the V. fischeri symbionts is optimal above 24 degrees C and is not enhanced by aldehyde addition. Also, V. fischeri strains were markedly more successful than V. logei at colonizing the light organs of juvenile Euprymna scolopes, especially at 26 degrees C. These findings have important implications for our understanding of the ecological dynamics and evolution of cooperative, and perhaps pathogenic, associations of Vibrio spp. with their animal hosts.

  11. Avaliação ecotoxicológica de efluentes de celulose branqueada de eucalipto ao longo do tratamento biológico

    OpenAIRE

    Martins, Daniel Von Rondon

    2008-01-01

    O presente estudo teve como objetivo avaliar a toxicidade de efluentes de celulose branqueada de eucalipto. Inicialmente foi feita uma caracterização físicoquímica das amostras, em diferentes pontos ao longo do tratamento, e posteriormente para estes mesmos pontos foi avaliada a toxicidade com quatro organismos-teste: para toxicidade aguda: a) Vibrio fischeri (sistema Microtox®) e b) Daphnia similis; para toxicidade crônica: c) Ceriodaphnia dubia e d) Pseudokirchneriella subcapitata. Para a r...

  12. Sampling the light-organ microenvironment of Euprymna scolopes: description of a population of host cells in association with the bacterial symbiont Vibrio fischeri.

    Science.gov (United States)

    Nyholm, S V; McFall-Ngai, M J

    1998-10-01

    The symbiosis between the squid Euprymna scolopes and the luminous bacterium Vibrio fischeri has a pronounced diel rhythm, one component of which is the venting of the contents of the light organ into the surrounding seawater each day at dawn. In this study, we explored the use of this behavior to sample the microenvironment of the light-organ crypts. Intact crypt contents, which emerge from the lateral pores of the organ as a thick paste-like exudate, were collected from anesthetized host animals that had been exposed to a light cue. Microscopy revealed that the expelled material is composed of a conspicuous population of host cells in association with the bacterial symbionts, all of which are embedded in a dense acellular matrix that strongly resembles the bacteria-based biofilms described in other systems. Assays of the viability of expelled crypt cells revealed no dead bacterial symbionts and a mixture of live and dead host cells. Analyses of the ultrastructure, biochemistry, and phagocytic activity of a subset of the host cell population suggested that some of these cells are macrophage-like molluscan hemocytes.

  13. Assessment of peracetic acid disinfected effluents by microbiotests.

    Science.gov (United States)

    Antonelli, M; Mezzanotte, V; Panouillères, M

    2009-09-01

    Bioassays were performed by commercially available kits on peracetic acid (PAA) solutions, at different concentrations, and on secondary effluents (from two different wastewater treatment plants) after disinfection at bench-scale, considering both samples containing residual active PAA and the same samples where residual PAA was quenched. Four indicator organisms were used: Vibrio fischeri, Thamnocephalus platyurus, Daphnia magna, and Selenastrum capricornutum. The experiments lead to conclude that Thamnocephalus platyurus is a very sensitive organism, probably not adequate to perform a reliable toxicity assessment of effluents for monitoring purposes. The presence of specific organic compounds deriving from human metabolism and urban pollution, even at very low concentrations, can affect the results of bioassays, especially those performed on Vibrio fischeri. PAA is toxic for bacteria and crustaceans even at concentrations lower than the ones commonly used in wastewater disinfection (2-5 mg/L), while its effect on algae is smaller. The toxic effect on bacteria was expected, as PAA is used for disinfection, but its possible influence on biological processes in the receiving aquatic environment should be considered. Toxicity on crustaceans would confirm the fact that discharging disinfected effluents could raise some environmental problems.

  14. The squid-Vibrio symbioses: from demes to genes.

    Science.gov (United States)

    Kimbell, Jennifer R; McFall-Ngai, Margaret J

    2003-04-01

    The monospecific light organ association between the Hawaiian sepiolid squid Euprymna scolopes and the marine luminous bacterium Vibrio fischeri has been used as a model for the study of the most common type of coevolved animal-bacterial interaction; i.e., the association of Gram-negative bacteria with the extracellular apical surfaces of polarized epithelia. Analysis of the squid-vibrio symbiosis has ranged from characterizations of the harvesting mechanisms by which the host ensures colonization by the appropriate symbiont to identification of bacteria-induced changes in host gene expression that accompany the establishment and maintenance of the relationship. Studies of this model have been enhanced by extensive collaboration with microbiologists, who are able to manipulate the genetics of the bacterial symbiont. The results of our studies have indicated that initiation and persistence of the association requires a complex, reciprocal molecular dialogue between these two phylogenetically distant partners.

  15. LC-MS/MS-based proteome profiling in Daphnia pulex and Daphnia longicephala: the Daphnia pulex genome database as a key for high throughput proteomics in Daphnia

    Directory of Open Access Journals (Sweden)

    Mayr Tobias

    2009-04-01

    Full Text Available Abstract Background Daphniids, commonly known as waterfleas, serve as important model systems for ecology, evolution and the environmental sciences. The sequencing and annotation of the Daphnia pulex genome both open future avenues of research on this model organism. As proteomics is not only essential to our understanding of cell function, and is also a powerful validation tool for predicted genes in genome annotation projects, a first proteomic dataset is presented in this article. Results A comprehensive set of 701,274 peptide tandem-mass-spectra, derived from Daphnia pulex, was generated, which lead to the identification of 531 proteins. To measure the impact of the Daphnia pulex filtered models database for mass spectrometry based Daphnia protein identification, this result was compared with results obtained with the Swiss-Prot and the Drosophila melanogaster database. To further validate the utility of the Daphnia pulex database for research on other Daphnia species, additional 407,778 peptide tandem-mass-spectra, obtained from Daphnia longicephala, were generated and evaluated, leading to the identification of 317 proteins. Conclusion Peptides identified in our approach provide the first experimental evidence for the translation of a broad variety of predicted coding regions within the Daphnia genome. Furthermore it could be demonstrated that identification of Daphnia longicephala proteins using the Daphnia pulex protein database is feasible but shows a slightly reduced identification rate. Data provided in this article clearly demonstrates that the Daphnia genome database is the key for mass spectrometry based high throughput proteomics in Daphnia.

  16. Toxicity of Single and Mixed Contaminants in Seawater Measured with Acute Toxicity Bioassays

    Directory of Open Access Journals (Sweden)

    A.R. Fernandez-Alba

    2002-01-01

    Full Text Available Different types of organic pollutants commonly detected in seawater have been evaluated by acute toxicity bioassays. Vibrio fischeri, Daphnia magna, and Selenastrum capricornotum were selected to test toxic effects of individual compounds and mixtures of these compounds, obtaining EC50 values in the range of 0.001 to 28.9 mg/l. In the case of mixtures, synergistic toxic responses were seen for a clear majority of the cases (>60%. Mixtures containing methyl-tertiary-butyl ether (MTBE exhibit accelerated processes that result in a change in concentration required to produce a toxic effect; for example, in the case of mixtures containing MTBE and Diuron and Dichlofluanid.

  17. A novel bacteriocin-like substance (BLIS) from a pathogenic strain of Vibrio harveyi.

    Science.gov (United States)

    Prasad, Sathish; Morris, Peter C; Hansen, Rasmus; Meaden, Philip G; Austin, Brian

    2005-09-01

    Inter-strain and inter-species inhibition mediated by a bacteriocin-like inhibitory substance (BLIS) from a pathogenic Vibrio harveyi strain VIB 571 was demonstrated against four isolates of the same species, and one culture each of a Vibrio sp., Vibrio fischeri, Vibrio gazogenes and Vibrio parahaemolyticus. The crude BLIS, which was obtained by ammonium-sulphate precipitation of the cell-free supernatant of a 72 h broth culture of strain VIB 571, was inactivated by lipase, proteinase K, pepsin, trypsin, pronase E, SDS and incubation at > or =60 degrees C for 10 min. The activity was stable between pH 2-11 for at least 5 h. Anion-exchange chromatography, gel filtration, SDS-PAGE and two-dimensional gel electrophoresis revealed the presence of a single major peak, comprising a protein with a pI of approximately 5.4 and a molecular mass of approximately 32 kDa. The N-terminal amino acid sequence of the protein comprised Asp-Glu-Tyr-Ile-Ser-X-Asn-Lys-X-Ser-Ser-Ala-Asp-Ile (with X representing cysteine or modified amino acid residues). A similarity search based on the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) generated peptide masses and the N-terminal sequence did not yield any significant matches.

  18. Testes de toxicidade aguda através de bioensaios no extrato solubilizado dos resíduos classe II A - não inertes e classe II B - inertes Acute toxicity tests by bioassays applied to the solubilized extracts of solid wastes class II A - non inerts and class II B - inerts

    Directory of Open Access Journals (Sweden)

    Nébora Liz Vendramin Brasil Rodrigues

    2007-03-01

    Full Text Available A grande diversidade de substâncias potencialmente tóxicas contribuem para a deterioração do meio ambiente. O objetivo deste trabalho foi propor a utilização de bioensaios, através de testes de toxicidade aguda com Daphnia magna e Vibrio fischeri, como mais um parâmetro a ser analisado no extrato solubilizado dos resíduos que, segundo a NBR 10004/04 fossem classificados como classe II A - não inertes ou classe II B - inertes. Realizaram-se, também, testes de toxicidade no drenado dos aterros classe II A e II B. Verificou-se que a toxicidade foi constatada nos extratos solubilizados dos 18 resíduos analisados e que, apenas três das amostras estariam próprias para lançamento, ou seja os resíduos 04, 14 e 15. Já, a toxicidade encontrada no drenado dos aterros, ficou muito superior do que a toxicidade de cada extrato solubilizado analisado separadamente.A great diversity of substances potencially toxic contributes to the deterioration of the environment. The aim of this research was to propose the use of bioassays using Daphnia magna and Vibrio fischeri, as another parameter to be analyzed in the solubilized extraction of waste according to NBR 10004/04 and classified as class II A - non inerts or class II B - inerts. Besides, another test was performed to measure the level of toxicity in the drainage of the landfill class II A and II B. It was verified that the toxicity found in the solubilized extracts of the 18 wastes analysed.Only 3 wastes (04, 14 and 15 were within the emission limits. On the other hand the toxicity found in the drainage of the landfill, from which all the samples came from, was much higher than the individual one.

  19. A New Niche for Vibrio logei, the Predominant Light Organ Symbiont of Squids in the Genus Sepiola

    OpenAIRE

    Fidopiastis, Pat M.; von Boletzky, Sigurd; Ruby, Edward G.

    1998-01-01

    Two genera of sepiolid squids—Euprymna, found primarily in shallow, coastal waters of Hawaii and the Western Pacific, and Sepiola, the deeper-, colder-water-dwelling Mediterranean and Atlantic squids—are known to recruit luminous bacteria into light organ symbioses. The light organ symbiont of Euprymna spp. is Vibrio fischeri, but until now, the light organ symbionts of Sepiola spp. have remained inadequately identified. We used a combination of molecular and physiological characteristics to ...

  20. ORF Alignment: NC_006841 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available NC_006841 gi|59714046 >1gntA 1 552 1 553 0.0 ... ref|YP_206821.1| hydroxylamine reduc...tase [Vibrio fischeri ES114] gb|AAW87933.1| ... hydroxylamine reductase [Vibrio fischeri ES114] ...

  1. Ecotoxicological Assessment of Sediment Leachates of Small Watercourses in the Brno City Suburban Area (South Moravia, Czech Republic

    Directory of Open Access Journals (Sweden)

    Miroslava Beklová

    2010-01-01

    Full Text Available Sediments of two small watercourses Leskava and Troubsky Brook in the Brno city suburban area were examined for their ecotoxicity. Using a standard procedure, extracts of the sediments were prepared for diagnostic tests. These extracts were tested for acute toxicity to fresh-water organisms. The ecotoxicological tests were performed on the fresh-water alga Pseudokirchneriella subcapitata, the vascular water plant Lemna minor, on a representative of invertebrates – the water flea Daphnia magna and on the Xenopus laevis frog embryo and luminiscent Vibrio fischeri bacteria. Possible toxic effects were evaluated using the test determining the inhibition of the growth of white mustard root Sinapis alba. Results of ecotoxicological assessment of sediment leachates showed that their quality varied significantly during the year. Differences were found between results of sediment evaluations from different collection profiles, which may indicate effects of point source pollution. Of the ecotoxicological tests used, the most sensitive organisms included the green algae Pseudokirchneriella subcapitata, bioluminiscent bacteria Vibrio fischeri and the African clawed frog Xenopus laevis. The highest concentrations of arsenic were found by chemical analysis in both spring and autumn sediment leachate samples collected at Site L1 (Leskava. The highest organic pollutant concentrations were found in autumn sediment leachate samples from Site L1. In total PAH sums, phenanthrene was the dominant pollutant at all the sites investigated.

  2. Removal of toxicity the pharmaceutical propranolol and your mixture with fluoxetine hydrochloride in aqueous solution using radiation with electron beam

    International Nuclear Information System (INIS)

    Boiani, Nathalia Fonseca

    2016-01-01

    Environmental health has been damage due to incorrect disposal of products and by-products. Among emerging pollutants it is possible to account with several pharmaceuticals, causing those problems when disposed in the environment by effluents. Conventional processing techniques are insufficient in removal of the pharmaceuticals, for having resistant waste and low biodegradability. Thus the advanced oxidation processes have been studied as an alternative for the treatment of different types of effluents. The objective of this study was to apply the process of irradiation with electron beam in order to reduce the toxic effects of propranolol, and the mixture with fluoxetine hydrochloride in aqueous solution. Ecotoxicological tests conducted with propranolol, and the mixture with fluoxetine hydrochloride, for Daphnia similis microcrustacean, and the Vibrio fischeri bacterium. It was observed that D. similis was more sensitive to propranolol drug and to the mixture, when compared to bacterium V.fischeri. After being subjected to the treatment with ionizing radiation, all applied doses to the propranolol and the mixture, showed significant reduction of toxicity, for D. similis. Different were the results for V. fischeri, when only 5.0 kGy reduced toxicity to propranolol. The mixture of pharmaceuticals required 2.5 and 5.0 kGy for reducing toxicity. 5.0 kGy showed the best removal efficiency for toxicity: 79.94 % for D. similis and 15.64 % for V. fischeri, when exposed to propranolol. The mixture reduction efficacy were 81.59% and 26.93 % for D.similis and V.fischeri, respectively. (author)

  3. Removal of toxicity the pharmaceutical propranolol and your mixture with fluoxetine hydrochloride in aqueous solution using radiation with electron beam; Remocao da toxicidade do farmaco propranolol e de sua mistura com cloridrato de fluoxetina em solucao aquosa empregando irradiacao com feixe de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Boiani, Nathalia Fonseca

    2016-07-01

    Environmental health has been damage due to incorrect disposal of products and by-products. Among emerging pollutants it is possible to account with several pharmaceuticals, causing those problems when disposed in the environment by effluents. Conventional processing techniques are insufficient in removal of the pharmaceuticals, for having resistant waste and low biodegradability. Thus the advanced oxidation processes have been studied as an alternative for the treatment of different types of effluents. The objective of this study was to apply the process of irradiation with electron beam in order to reduce the toxic effects of propranolol, and the mixture with fluoxetine hydrochloride in aqueous solution. Ecotoxicological tests conducted with propranolol, and the mixture with fluoxetine hydrochloride, for Daphnia similis microcrustacean, and the Vibrio fischeri bacterium. It was observed that D. similis was more sensitive to propranolol drug and to the mixture, when compared to bacterium V.fischeri. After being subjected to the treatment with ionizing radiation, all applied doses to the propranolol and the mixture, showed significant reduction of toxicity, for D. similis. Different were the results for V. fischeri, when only 5.0 kGy reduced toxicity to propranolol. The mixture of pharmaceuticals required 2.5 and 5.0 kGy for reducing toxicity. 5.0 kGy showed the best removal efficiency for toxicity: 79.94 % for D. similis and 15.64 % for V. fischeri, when exposed to propranolol. The mixture reduction efficacy were 81.59% and 26.93 % for D.similis and V.fischeri, respectively. (author)

  4. Assessment of toxicity and genotoxicity of the reactive azo dyes Remazol Black B and Remazol Orange 3R and effectiveness of electron beam irradiation in the reduction of color and toxic effects

    International Nuclear Information System (INIS)

    Pinheiro, Alessandro de Sa

    2011-01-01

    The textile industries play an important role in national and global economy. But, their activities are considered potentially polluting. The use of large volumes of water and the production of colored wastewater with high organic matter are among the main issues raised, especially during the stage of dyeing and washing of the textile process. The reactive azo dyes are the main colors used in the industry for dyeing of cotton in Brazil and worldwide. Because of its low setting and variations in the fiber production process, about 30% of the initial concentration used in the dyeing baths are lost and will compose the final effluent. These compounds have a low biodegradability, are highly soluble in water and therefore are not completely removed by conventional biological processes. In addition, other processes do not promote degradation but the transference to solid environment. The dyes discarded without treatment in the water body can cause aesthetic modifications, alter photosynthesis and gas solubility, as well as being toxic and genotoxic. The main objectives of this study were to evaluate the toxicity and genotoxicity of two reactive azo dyes (Remazol Black B - RPB and Remazol Orange 3R - R3AR) and the percentage of color and toxicity reduction after the use of electron beam radiation. The acute toxicity assays performed with Vibrio fischeri, Daphnia similis and Biomphalaria glabrata showed different response patterns for dyes. The different chemical forms of dyes were slightly toxic to Vibrio fischeri and only the RPB dye (vinylsulphone) was toxic (EC50 15min = 6,23 mg L-1). In tests with Daphnia similis, the dye RPB was slightly toxic in its pattern form, sulphatoethylsulphone, (CE50 48h = 91,25 mg L -1 ) and showed no toxicity in other chemical forms. However, the RA3R dye was toxic to the dafnids and the vinylsulphone form very toxic (EC50 48h = 0,54 mg L-1). No toxicity was observed in Biomphalaria glabrata assays. Chronic toxicity was assessed with the

  5. Whole acute toxicity removal from industrial and domestic effluents treated by electron beam radiation: emphasis on anionic surfactants

    International Nuclear Information System (INIS)

    Moraes, M.C.F.; Romanelli, M.F; Sena, H.C.; Pasqualini da Silva, G.; Sampa, M.H.O.; Borrely, S.I.

    2004-01-01

    Electron beam radiation has been applied to improve real industrial and domestic effluents received by Suzano wastewater treatment plant. Radiation efficacy has been evaluated as toxicity reduction, using two biological assays. Three sites were sampled and submitted for toxicity assays, anionic surfactant determination and electron beam irradiation. This paper shows the reduction of acute toxicity for both test-organisms, the marine bacteria Vibrio fischeri and the crustacean Daphnia similis. The raw toxic effluents exibitted from 0.6 ppm up to 11.67 ppm for anionic surfactant before being treated by the electron beam. Radiation processing resulted in reduction of the acute toxicity as well as surfactant removal. The final biological effluent was in general less toxic than other sites but the presence of anionic surfactants was evidenced

  6. Whole acute toxicity removal from industrial and domestic effluents treated by electron beam radiation: emphasis on anionic surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, M.C.F. E-mail: mariacristinafm@uol.com.br; Romanelli, M.F; Sena, H.C.; Pasqualini da Silva, G.; Sampa, M.H.O.; Borrely, S.I

    2004-10-01

    Electron beam radiation has been applied to improve real industrial and domestic effluents received by Suzano wastewater treatment plant. Radiation efficacy has been evaluated as toxicity reduction, using two biological assays. Three sites were sampled and submitted for toxicity assays, anionic surfactant determination and electron beam irradiation. This paper shows the reduction of acute toxicity for both test-organisms, the marine bacteria Vibrio fischeri and the crustacean Daphnia similis. The raw toxic effluents exibitted from 0.6 ppm up to 11.67 ppm for anionic surfactant before being treated by the electron beam. Radiation processing resulted in reduction of the acute toxicity as well as surfactant removal. The final biological effluent was in general less toxic than other sites but the presence of anionic surfactants was evidenced.

  7. Evaluation of the toxicity of fluids employed in the metallic tool industrial machining using aquatic ecotoxicology

    International Nuclear Information System (INIS)

    Coelho, Ricardo dos Santos

    2006-01-01

    Eco toxicological analyses have being used to monitor environmental samples, industrial effluents and complex substances. With the objective to analyze the toxicity of cutting fluids used in the machinery industry, acute toxicity test with species of three different trophic levels: Vibrio fischeri, Daphnia similis, Daphnia laevis e Danio rerio, were performing. The samples of fluids were analyzed by COD, phenol, pH, color, density and surfactants. The physical and chemical parameters are the according with the brazilian law, CONAMA 357 (D.O.U. 2005). The results of the toxicity tests showed that the cutting fluids have high toxicity to the organisms used in this study and the gamma radiation treatment was not efficient to decrease the matrix. The biodegradation in soil demonstrated be effective to the cutting fluids and the indigenous bacteria were identified and isolated to possible treatment of soils contaminated with these kinds of substances. The monitoring and management of residues of cutting fluids are necessary to preservation of aquatic live, in consequence of their high toxicity. (author)

  8. The ecoresponsive genome of Daphnia pulex

    Energy Technology Data Exchange (ETDEWEB)

    Colbourne, John K.; Pfrender, Michael E.; Gilbert, Donald; Thomas, W. Kelley; Tucker, Abraham; Oakley, Todd H.; Tokishita, Shinichi; Aerts, Andrea; Arnold, Georg J.; Basu, Malay Kumar; Bauer, Darren J.; Caceres, Carla E.; Carmel, Liran; Casola, Claudio; Choi, Jeong-Hyeon; Detter, John C.; Dong, Qunfeng; Dusheyko, Serge; Eads, Brian D.; Frohlich, Thomas; Geiler-Samerotte, Kerry A.; Gerlach, Daniel; Hatcher, Phil; Jogdeo, Sanjuro; Krijgsveld, Jeroen; Kriventseva, Evgenia V; Kültz, Dietmar; Laforsch, Christian; Lindquist, Erika; Lopez, Jacqueline; Manak, Robert; Muller, Jean; Pangilinan, Jasmyn; Patwardhan, Rupali P.; Pitluck, Samuel; Pritham, Ellen J.; Rechtsteiner, Andreas; Rho, Mina; Rogozin, Igor B.; Sakarya, Onur; Salamov, Asaf; Schaack, Sarah; Shapiro, Harris; Shiga, Yasuhiro; Skalitzky, Courtney; Smith, Zachary; Souvorov, Alexander; Sung, Way; Tang, Zuojian; Tsuchiya, Dai; Tu, Hank; Vos, Harmjan; Wang, Mei; Wolf, Yuri I.; Yamagata, Hideo; Yamada, Takuji; Ye, Yuzhen; Shaw, Joseph R.; Andrews, Justen; Crease, Teresa J.; Tang, Haixu; Lucas, Susan M.; Robertson, Hugh M.; Bork, Peer; Koonin, Eugene V.; Zdobnov, Evgeny M.; Grigoriev, Igor V.; Lynch, Michael; Boore, Jeffrey L.

    2011-02-04

    This document provides supporting material related to the sequencing of the ecoresponsive genome of Daphnia pulex. This material includes information on materials and methods and supporting text, as well as supplemental figures, tables, and references. The coverage of materials and methods addresses genome sequence, assembly, and mapping to chromosomes, gene inventory, attributes of a compact genome, the origin and preservation of Daphnia pulex genes, implications of Daphnia's genome structure, evolutionary diversification of duplicated genes, functional significance of expanded gene families, and ecoresponsive genes. Supporting text covers chromosome studies, gene homology among Daphnia genomes, micro-RNA and transposable elements and the 46 Daphnia pulex opsins. 36 figures, 50 tables, 183 references.

  9. Enumeration of Vibrio parahaemolyticus in the viable but nonculturable state using direct plate counts and recognition of individual gene fluorescence in situ hybridization.

    Science.gov (United States)

    Griffitt, Kimberly J; Noriea, Nicholas F; Johnson, Crystal N; Grimes, D Jay

    2011-05-01

    Vibrio parahaemolyticus is a gram-negative, halophilic bacterium indigenous to marine and estuarine environments and it is capable of causing food and water-borne illness in humans. It can also cause disease in marine animals, including cultured species. Currently, culture-based techniques are used for quantification of V. parahaemolyticus in environmental samples; however, these can be misleading as they fail to detect V. parahaemolyticus in a viable but nonculturable (VBNC) state which leads to an underestimation of the population density. In this study, we used a novel fluorescence visualization technique, called recognition of individual gene fluorescence in situ hybridization (RING-FISH), which targets chromosomal DNA for enumeration. A polynucleotide probe labeled with Cyanine 3 (Cy3) was created corresponding to the ubiquitous V. parahaemolyticus gene that codes for thermolabile hemolysin (tlh). When coupled with the Kogure method to distinguish viable from dead cells, RING-FISH probes reliably enumerated total, viable V. parahaemolyticus. The probe was tested for sensitivity and specificity against a pure culture of tlh(+), tdh(-), trh(-)V. parahaemolyticus, pure cultures of Vibrio vulnificus, Vibrio harveyi, Vibrio alginolyticus and Vibrio fischeri, and a mixed environmental sample. This research will provide additional tools for a better understanding of the risk these environmental organisms pose to human health. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Identification of a novel UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) from Vibrio fischeri that confers high fosfomycin resistance in Escherichia coli

    Digital Repository Service at National Institute of Oceanography (India)

    Kumar, S.; Parvathi, A.; Hernandez, R.L.; Cadle, K.M.; Varela, M.F.

    -positive and Gram-negative bacteria. The antibiotic is used to treat uncomplicated urinary tract infections (UTIs) caused by E. coli and Enterococcus faecalis world wide (Falagas et al. 2008). Some pathogenic bacteria such as Mycobacterium tuberculosis...A proteins are naturally resistant to fosfomycin, such as in the case of Mycobacterium tuberculosis and Chlamydia trachomatis (DeSmet et al. 1999; McCoy et al. 2003). We compared the deduced amino acid sequence of V. fischeri MurA with the homologous...

  11. Decoloration and detoxification of effluents by ionizing radiation

    International Nuclear Information System (INIS)

    Borrely, Sueli I.; Morais, Aline V.; Rosa, Jorge M.; Badaró-Pedroso, Cintia; Conceição Pereira, Maria da; Higa, Marcela C.

    2016-01-01

    Three distinct textile samples were investigated for color and toxicity (S1–chemical/textile industry; S2–final textile effluent; S3 - standard textile produced effluent–untreated blue). Radiation processing of these samples were carried out at Dynamitron Electron Beam Accelerator and color and toxicity removal were determined: color removal by radiation was 96% (40 kGy, S1); 55% (2.5 kGy, S2) and 90% (2.5 kGy, S3). Concerning toxicity assays, Vibrio fischeri luminescent bacteria demonstrated higher reduction after radiation than the other systems: removal efficiencies were 33% (20 kGy, S1); 55% (2.5 kGy, S2) and 33% (2.5 kGy, S3). Daphnia similis and Brachionus plicatilis fitted well for S3 effluents. Hard toxic volumes into biological treatment plant may be avoided if radiation would be previously applied in a real plant. Results reveled how indispensable is to run toxicity to more than one living-organism. - Highlights: • 2.5 kGy was enough for decoloration and detoxification of S2 and S3. • S1 effluents were very toxic and required at least 20 kGy for detoxification. • Radiation processing reduced toxicity for 100% of treated samples. • V. fischeri was the best tool for toxicity measurements.

  12. Toxicity of anthelmintic drugs (fenbendazole and flubendazole) to aquatic organisms.

    Science.gov (United States)

    Wagil, Marta; Białk-Bielińska, Anna; Puckowski, Alan; Wychodnik, Katarzyna; Maszkowska, Joanna; Mulkiewicz, Ewa; Kumirska, Jolanta; Stepnowski, Piotr; Stolte, Stefan

    2015-02-01

    Flubendazole (FLU) and fenbendazole (FEN) belong to benzimidazoles-pharmaceuticals widely used in veterinary and human medicine for the treatment of intestinal parasites as well as for the treatment of systemic worm infections. In recent years, usage of these drugs increased, which resulted in a larger contamination of the environment and possible negative effects on biota. Hence, in our research, we investigated an aquatic ecotoxicity of these pharmaceuticals towards: marine bacteria (Vibrio fischeri), green algae (Scenedesmus vacuolatus), duckweed (Lemna minor) and crustacean (Daphnia magna). Ecotoxicity tests were combined with chemical analysis in order to investigate the actual exposure concentration of the compounds used in the experiment as well as to stability and adsorption studies. As a result, study evaluating sensitivity of different aquatic organisms to these compounds and new ecotoxicological data is presented. The strongest negative impact of FLU and FEN was observed to D. magna.

  13. Cyanobacteria facilitate parasite epidemics in Daphnia.

    Science.gov (United States)

    Tellenbach, C; Tardent, N; Pomati, F; Keller, B; Hairston, N G; Wolinska, J; Spaak, P

    2016-12-01

    The seasonal dominance of cyanobacteria in the phytoplankton community of lake ecosystems can have severe implications for higher trophic levels. For herbivorous zooplankton such as Daphnia, cyanobacteria have poor nutritional value and some species can produce toxins affecting zooplankton survival and reproduction. Here we present another, hitherto largely unexplored aspect of cyanobacteria, namely that they can increase Daphnia susceptibility to parasites. In a 12-yr monthly time-series analysis of the Daphnia community in Greifensee (Switzerland), we observed that cyanobacteria density correlated significantly with the epidemics of a common gut parasite of Daphnia, Caullerya mesnili, regardless of what cyanobacteria species was present or whether it was colonial or filamentous. The temperature from the previous month also affected the occurrence of Caullerya epidemics, either directly or indirectly by the promotion of cyanobacterial growth. A laboratory experiment confirmed that cyanobacteria increase the susceptibility of Daphnia to Caullerya, and suggested a possible involvement of cyanotoxins or other chemical traits of cyanobacteria in this process. These findings expand our understanding of the consequences of toxic cyanobacterial blooms for lake ecosystems and might be relevant for epidemics experienced by other aquatic species. © 2016 by the Ecological Society of America.

  14. Canine visceral leishmaniasis in the metropolitan area of São Paulo: Pintomyia fischeri as potential vector of Leishmania infantum

    Directory of Open Access Journals (Sweden)

    Galvis-Ovallos Fredy

    2017-01-01

    Full Text Available American visceral leishmaniasis is a zoonosis caused by Leishmania infantum and transmitted mainly by Lutzomyia longipalpis. However, canine cases have been reported in the absence of this species in the Greater São Paulo region, where Pintomyia fischeri and Migonemyia migonei are the predominant species. This raises the suspicion that they could be acting as vectors. Therefore, this study sought to investigate specific vector capacity parameters of these species and to compare them with those of Lu. longipalpis s.l. Among these parameters the blood feeding rate, the survival, and the susceptibility to the development of Le. infantum were evaluated for the three species, and the attractiveness of dogs to Pi. fischeri and Mg. migonei was evaluated. The estimated interval between blood meals was shorter for Lu. longipalpis s.l, followed by Pi. fischeri and Mg. migonei. The infection rate with Le. infantum flagellates in Lu. longipalpis was 9.8%, in Pi. fischeri 4.8%, and in Mg. migonei nil. The respective infective life expectancies (days of Lu. longipalpis, Mg. migonei, and Pi. fischeri were 2.4, 1.94, and 1.68. Both Pi. fischeri and Mg. migonei were captured in the kennel with a predominance (95% of Pi. fischeri. Considering the great attractiveness of dogs to Pi. fischeri, its susceptibility to infection by Le. infantum, infective life expectancies, and predominance in Greater São Paulo, this study presents evidence of Pi. fischeri as a potential vector of this parasite in the region.

  15. BEHAVIORAL AND PHYSIOLOGICAL RESPONSES OF DAPHNIA MAGNA, CHLORELLA VULGARIS, LEPOMIS MACROCHIRUS, AND VIBRIO FISCHERI TO TOLUENE

    Science.gov (United States)

    The research presented here is a continuation of work designed to further the science of available and developing online toxicity monitors(OTMs) and how they may be most effectively deployed in a watershed management plan and/or water quality early warning system. Source waters o...

  16. Understanding the Role of Host Hemocytes in a Squid/Vibrio Symbiosis Using Transcriptomics and Proteomics

    Directory of Open Access Journals (Sweden)

    Andrew J. Collins

    2012-05-01

    Full Text Available The symbiosis between the squid, Euprymna scolopes, and the bacterium, Vibrio fischeri, serves as a model for understanding interactions between beneficial bacteria and animal hosts. The establishment and maintenance of the association is highly specific and depends on the selection of V. fischeri and exclusion of non-symbiotic bacteria from the environment. Current evidence suggests that the host’s cellular innate immune system, in the form of macrophage-like hemocytes, helps to mediate host tolerance of V. fischeri. To begin to understand the role of hemocytes in this association, we analyzed these cells by high-throughput 454 transcriptomic and liquid chromatography/ tandem mass spectrometry (LC-MS/MS proteomic analyses. 454 high-throughput sequencing produced 650,686 reads totaling 279.9 Mb while LC-MS/MS analyses of circulating hemocytes putatively identified 702 unique proteins. Several receptors involved with the recognition of microbial associated molecular patterns (MAMPs were identified. Among these was a complete open reading frame (ORF to a putative peptidoglycan recognition protein (EsPGRP5 that has conserved residues for amidase activity. Assembly of the hemocyte transcriptome showed EsPGRP5 had high coverage, suggesting it is among the 5% most abundant transcripts in circulating hemocytes. Other transcripts and proteins identified included members of the conserved NFκB signaling pathway, putative members of the complement pathway, the carbohydrate binding protein galectin, and cephalotoxin. Quantitative PCR of complement-related genes, cephalotoxin, EsPGRP5, and a nitric oxide synthase showed differential expression in circulating hemocytes isolated from adult squid with colonized light organs compared to those for which the symbionts were removed. These data suggest that the presence of the symbiont influences gene expression of the cellular innate immune system of the host.

  17. A soluble fatty acyl-acyl carrier protein synthetase from the bioluminescent bacterium Vibrio harveyi.

    Science.gov (United States)

    Byers, D M; Holmes, C G

    1990-01-01

    An enzyme catalyzing the ligation of long chain fatty acids to bacterial acyl carrier protein (ACP) has been detected and partially characterized in cell extracts of the bioluminescent bacterium Vibrio harveyi. Acyl-ACP synthetase activity (optimal pH 7.5-8.0) required millimolar concentrations of ATP and Mg2+ and was slightly activated by Ca2+, but was inhibited at high ionic strength and by Triton X-100. ACP from either Escherichia coli (apparent Km = 20 microM) or V. harveyi was used as a substrate. Of the [14C]fatty acids tested as substrates (8-18 carbons), a preference for fatty acids less than or equal to 14 carbons in length was observed. Vibrio harveyi acyl-ACP synthetase appears to be a soluble hydrophilic enzyme on the basis of subcellular fractionation and Triton X-114 phase partition assay. The enzyme was not coinduced with luciferase activity or light emission in vivo during the late exponential growth phase in liquid culture. Acyl-ACP synthetase activity was also detected in extracts from the luminescent bacterium Vibrio fischeri, but not Photobacterium phosphoreum. The cytosolic nature and enzymatic properties of V. harveyi acyl-ACP synthetase indicate that it may have a different physiological role than the membrane-bound activity of E. coli, which has been implicated in phosphatidylethanolamine turnover. Acyl-ACP synthetase activity in V. harveyi could be involved in the intracellular activation and elongation of exogenous fatty acids that occurs in this species or in the reactivation of free myristic acid generated by luciferase.

  18. Elongation of exogenous fatty acids by the bioluminescent bacterium Vibrio harveyi

    Energy Technology Data Exchange (ETDEWEB)

    Byers, D.M.

    1989-01-01

    Bioluminescent bacteria require myristic acid (C14:0) to produce the myristaldehyde substrate of the light-emitting luciferase reaction. Since both endogenous and exogenous C14:0 can be used for this purpose, the metabolism of exogenous fatty acids by luminescent bacteria has been investigated. Both Vibrio harveyi and Vibrio fischeri incorporated label from (1-14C)myristic acid (C14:0) into phospholipid acyl chains as well as into CO2. In contrast, Photobacterium phosphoreum did not exhibit phospholipid acylation or beta-oxidation using exogenous fatty acids. Unlike Escherichia coli, the two Vibrio species can directly elongate fatty acids such as octanoic (C8:0), lauric (C12:0), and myristic acid, as demonstrated by radio-gas liquid chromatography. The induction of bioluminescence in late exponential growth had little effect on the ability of V. harveyi to elongate fatty acids, but it did increase the amount of C14:0 relative to C16:0 labeled from (14C)C8:0. This was not observed in a dark mutant of V. harveyi that is incapable of supplying endogenous C14:0 for luminescence. Cerulenin preferentially decreased the labeling of C16:0 and of unsaturated fatty acids from all 14C-labeled fatty acid precursors as well as from (14C)acetate, suggesting that common mechanisms may be involved in elongation of fatty acids from endogenous and exogenous sources. Fatty acylation of the luminescence-related synthetase and reductase enzymes responsible for aldehyde synthesis exhibited a chain-length preference for C14:0, which also was indicated by reverse-phase thin-layer chromatography of the acyl groups attached to these enzymes. The ability of V. harveyi to activate and elongate exogenous fatty acids may be related to an adaptive requirement to metabolize intracellular C14:0 generated by the luciferase reaction during luminescence development.

  19. Elongation of exogenous fatty acids by the bioluminescent bacterium Vibrio harveyi

    International Nuclear Information System (INIS)

    Byers, D.M.

    1989-01-01

    Bioluminescent bacteria require myristic acid (C14:0) to produce the myristaldehyde substrate of the light-emitting luciferase reaction. Since both endogenous and exogenous C14:0 can be used for this purpose, the metabolism of exogenous fatty acids by luminescent bacteria has been investigated. Both Vibrio harveyi and Vibrio fischeri incorporated label from [1-14C]myristic acid (C14:0) into phospholipid acyl chains as well as into CO2. In contrast, Photobacterium phosphoreum did not exhibit phospholipid acylation or beta-oxidation using exogenous fatty acids. Unlike Escherichia coli, the two Vibrio species can directly elongate fatty acids such as octanoic (C8:0), lauric (C12:0), and myristic acid, as demonstrated by radio-gas liquid chromatography. The induction of bioluminescence in late exponential growth had little effect on the ability of V. harveyi to elongate fatty acids, but it did increase the amount of C14:0 relative to C16:0 labeled from [14C]C8:0. This was not observed in a dark mutant of V. harveyi that is incapable of supplying endogenous C14:0 for luminescence. Cerulenin preferentially decreased the labeling of C16:0 and of unsaturated fatty acids from all 14C-labeled fatty acid precursors as well as from [14C]acetate, suggesting that common mechanisms may be involved in elongation of fatty acids from endogenous and exogenous sources. Fatty acylation of the luminescence-related synthetase and reductase enzymes responsible for aldehyde synthesis exhibited a chain-length preference for C14:0, which also was indicated by reverse-phase thin-layer chromatography of the acyl groups attached to these enzymes. The ability of V. harveyi to activate and elongate exogenous fatty acids may be related to an adaptive requirement to metabolize intracellular C14:0 generated by the luciferase reaction during luminescence development

  20. Effects of symbiotic bacteria on chemical sensitivity of Daphnia magna.

    Science.gov (United States)

    Manakul, Patcharaporn; Peerakietkhajorn, Saranya; Matsuura, Tomoaki; Kato, Yasuhiko; Watanabe, Hajime

    2017-07-01

    The crustacean zooplankton Daphnia magna has been widely used for chemical toxicity tests. Although abiotic factors have been well documented in ecotoxicological test protocols, biotic factors that may affect the sensitivity to chemical compounds remain limited. Recently, we identified symbiotic bacteria that are critical for the growth and reproduction of D. magna. The presence of symbiotic bacteria on Daphnia raised the question as to whether these bacteria have a positive or negative effect on toxicity tests. In order to evaluate the effects of symbiotic bacteria on toxicity tests, bacteria-free Daphnia were prepared, and their chemical sensitivities were compared with that of Daphnia with symbiotic bacteria based on an acute immobilization test. The Daphnia with symbiotic bacteria showed higher chemical resistance to nonylphenol, fenoxycarb, and pentachlorophenol than bacteria-free Daphnia. These results suggested potential roles of symbiotic bacteria in the chemical resistance of its host Daphnia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The response of European Daphnia magna Straus and Australian Daphnia carinata King to changes in geomagnetic field.

    Science.gov (United States)

    Krylov, Viacheslav V; Bolotovskaya, Irina V; Osipova, Elena A

    2013-03-01

    This study investigates the effects of lifelong exposure to reversed geomagnetic and zero geomagnetic fields (the latter means absence of geomagnetic field) on the life history of Daphnia carinata King from Australia and Daphnia magna Straus from Europe. Considerable deviation in the geomagnetic field from the usual strength, leads to a decrease in daphnia size and life span. Reduced brood sizes and increased body length of neonates are observed in D. magna exposed to unusual magnetic background. The most apparent effects are induced by zero geomagnetic field in both species of Daphnia. A delay in the first reproduction in zero geomagnetic field is observed only in D. magna. No adaptive maternal effects to reversed geomagnetic field are found in a line of D. magna maintained in these magnetic conditions for eight generations. Integrally, the responses of D. magna to unusual geomagnetic conditions are more extensive than that in D. carinata. We suggest that the mechanism of the effects of geomagnetic field reversal on Daphnia may be related to differences in the pattern of distribution of the particles that have a magnetic moment, or to moving charged organic molecules owing to a change in combined outcome and orientation of the geomagnetic field and Earth's gravitational field. The possibility of modulation of self-oscillating processes with changes in geomagnetic field is also discussed.

  2. Effect of advanced oxidation processes (AOP's) on the toxicity of municipal landfill leachates

    Energy Technology Data Exchange (ETDEWEB)

    Slomczynska, B.; Slomczynski, T. [Inst. of Environmental Engineering Systems, Warsaw Univ. of Technology, Warsaw (Poland); Wasowski, J. [Inst. of Water Supply and Hydraulic Construction, Warsaw Univ. of Technology, Warsaw (Poland)

    2003-07-01

    The aim of present study was to assess the effect of AOP's (oxidation ozone and peroxide/ozone) on the toxicity of leachates from municipal landfill for Warsaw, Poland, using battery of tests. Advanced oxidation processes used to pre-treat leachates were carried out in laboratory conditions after their coagulation with the use of FeCl{sub 3}. The effects of the pre-treatment of leachates using the method of coagulation with FeCl{sub 3} depended on the concentration of organic compounds and with optimal conditions of the process ranged from 40 to 70%. Further pre-treatment of the leachates after coagulation, involving the use of oxidation with O{sub 3} and H{sub 2}O{sub 2}/O{sub 3}, did not caused significant decrease of leachate toxicity. The data of this study demonstrated the usefulness of the battery of tests using Daphnia magna, Artemia franciscana, Scenedesmus quadricauda and Vibrio fischeri for the toxicity evaluation of raw and pre-treated leachates. (orig.)

  3. Eco- and genotoxicity profiling of a rapeseed biodiesel using a battery of bioassays.

    Science.gov (United States)

    Eck-Varanka, Bettina; Kováts, Nora; Horváth, Eszter; Ferincz, Árpád; Kakasi, Balázs; Nagy, Szabolcs Tamás; Imre, Kornélia; Paulovits, Gábor

    2018-04-30

    Biodiesel is considered an important renewable energy source but still there is some controversy about its environmental toxicity, especially to aquatic life. In our study, the toxicity of water soluble fraction of biodiesel was evaluated in relatively low concentrations using a battery of bioassays: Vibrio fischeri bioluminescence inhibition, Sinapis alba root growth inhibition, Daphnia magna immobilization, boar semen live/dead ratio and DNA fragmentation and Unio pictorum micronucleus test. While the S. alba test indicated nutritive (stimulating) effect of the sample, the biodiesel exerted toxic effect in the aquatic tests. D. magna was the most sensitive with EC 50 value of 0.0226%. For genotoxicity assessment, the mussel micronucleus test (MNT) was applied, detecting considerable genotoxic potential of the biodiesel sample: it elucidated micronuclei formation already at low concentration of 3.3%. Although this test has never been employed in biodiesel eco/genotoxicity assessments, it seems a promising tool, based on its appropriate sensitivity, and representativity. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Evaluation of toxicity reduction of sodium dodecyl sulfate submitted to electron beam radiation

    Science.gov (United States)

    Romanelli, M. F.; Moraes, M. C. F.; Villavicencio, A. L. C. H.; Borrely, S. I.

    2004-09-01

    Surfactants, as detergent active substances, are an important source of pollution causing biological adverse effects to aquatic organisms. Several data have been showing ecological disturbance due to the high concentration of surfactants on receiving waters and on wastewater treatment plants. Ionizing radiation has been proved as an effective technology to decompose organic substances and few papers have included ecotoxicological aspects. This paper shows the reduction of acute toxicity of a specific surfactant, sodium dodecyl sulfate (SDS), when diluted in distilled water and submitted to electron beam radiation. The study included two test-organisms, the marine bacteria Vibrio fischeri and the crustacean Daphnia similis. Radiation processing resulted in an important acute toxicity removal for both assays, which can be summarized between 70% and 96%, using 3.0, 6.0, 9.0 and 12.0 kGy as radiation doses. Nevertheless, lower doses demonstrated better effect than 9.0 and 12.0 kGy and the bacterium assay was more sensitive to SDS than crustacean assay.

  5. Decoloration and detoxification of effluents by ionizing radiation

    Science.gov (United States)

    Borrely, Sueli I.; Morais, Aline V.; Rosa, Jorge M.; Badaró-Pedroso, Cintia; da Conceição Pereira, Maria; Higa, Marcela C.

    2016-07-01

    Three distinct textile samples were investigated for color and toxicity (S1-chemical/textile industry; S2-final textile effluent; S3 - standard textile produced effluent-untreated blue). Radiation processing of these samples were carried out at Dynamitron Electron Beam Accelerator and color and toxicity removal were determined: color removal by radiation was 96% (40 kGy, S1); 55% (2.5 kGy, S2) and 90% (2.5 kGy, S3). Concerning toxicity assays, Vibrio fischeri luminescent bacteria demonstrated higher reduction after radiation than the other systems: removal efficiencies were 33% (20 kGy, S1); 55% (2.5 kGy, S2) and 33% (2.5 kGy, S3). Daphnia similis and Brachionus plicatilis fitted well for S3 effluents. Hard toxic volumes into biological treatment plant may be avoided if radiation would be previously applied in a real plant. Results reveled how indispensable is to run toxicity to more than one living-organism.

  6. CRISPR/Cas-mediated targeted mutagenesis in Daphnia magna.

    Directory of Open Access Journals (Sweden)

    Takashi Nakanishi

    Full Text Available The water flea Daphnia magna has been used as an animal model in ecology, evolution, and environmental sciences. Thanks to the recent progress in Daphnia genomics, genetic information such as the draft genome sequence and expressed sequence tags (ESTs is now available. To investigate the relationship between phenotypes and the available genetic information about Daphnia, some gene manipulation methods have been developed. However, a technique to induce targeted mutagenesis into Daphnia genome remains elusive. To overcome this problem, we focused on an emerging genome editing technique mediated by the clustered regularly interspaced short palindromic repeats/CRISPR-associated (CRISPR/Cas system to introduce genomic mutations. In this study, we targeted a functionally conserved regulator of eye development, the eyeless gene in D. magna. When we injected Cas9 mRNAs and eyeless-targeting guide RNAs into eggs, 18-47% of the survived juveniles exhibited abnormal eye morphology. After maturation, up to 8.2% of the adults produced progenies with deformed eyes, which carried mutations in the eyeless loci. These results showed that CRISPR/Cas system could introduce heritable mutations into the endogenous eyeless gene in D. magna. This is the first report of a targeted gene knockout technique in Daphnia and will be useful in uncovering Daphnia gene functions.

  7. Ecotoxicity tests based on phototactic behaviour in Daphnia magna; Saggi di ecotossicita` con Daphnia magna basati sul comportamento fototattico

    Energy Technology Data Exchange (ETDEWEB)

    Dojmi di Delupis, Gianluigi [Istituto Superiore di Sanita`, Rome (Italy). Lab. di Tossicologia Comparata ed Ecotossicologia

    1997-03-01

    Zooplankton behaviour depending on light, such as phototaxis, is important, mainly in terms of its ecological significance, as, for example, in the role of phototaxis in the diurnal vertical migration of Daphnia magna, and its possible involvement in predator-prey relations. In Daphnia magna chemicals were found to induce roughly three types of phototaxis alteration: depression, enhancement and sign change. These phenomena are based on mechanisms that require further investigation. In spite of the complex photobehaviour of Daphnia magna and the scarce knowledge of toxic effects, it was possible to set up rapid and easy ecotoxicity tests by fixing certain experimental conditions.

  8. Methods for detecting acylated homoserine lactones produced by Gram-negative bacteria and their application in studies of AHL- production kinetics

    DEFF Research Database (Denmark)

    Ravn, L.; Christensen, Allan Beck; Molin, Søren

    2001-01-01

    and enabled an assessment of the kinetics of AHL- production of 3 strains (Serratia proteamaculans strain B5a, Erwinia carotovora ATCC 39048 and V. fischeri strain MJ-1). As expected, the production of AHL (OHHL) and luminescence in Vibrio fischeri strain MJ-1 increased faster than growth indicating up...

  9. Acute toxicity of anionic and non-ionic surfactants to aquatic organisms.

    Science.gov (United States)

    Lechuga, M; Fernández-Serrano, M; Jurado, E; Núñez-Olea, J; Ríos, F

    2016-03-01

    The environmental risk of surfactants requires toxicity measurements. As different test organisms have different sensitivity to the toxics, it is necessary to establish the most appropriate organism to classify the surfactant as very toxic, toxic, harmful or safe, in order to establish the maximum permissible concentrations in aquatic ecosystems. We have determined the toxicity values of various anionic surfactants ether carboxylic derivatives using four test organisms: the freshwater crustacean Daphnia magna, the luminescent bacterium Vibrio fischeri, the microalgae Selenastrum capricornutum (freshwater algae) and Phaeodactylum tricornutum (seawater algae). In addition, in order to compare and classify the different families of surfactants, we have included a compilation of toxicity data of surfactants collected from literature. The results indicated that V. fischeri was more sensitive to the toxic effects of the surfactants than was D. magna or the microalgae, which was the least sensitive. This result shows that the most suitable toxicity assay for surfactants may be the one using V. fischeri. The toxicity data revealed considerable variation in toxicity responses with the structure of the surfactants regardless of the species tested. The toxicity data have been related to the structure of the surfactants, giving a mathematical relationship that helps to predict the toxic potential of a surfactant from its structure. Model-predicted toxicity agreed well with toxicity values reported in the literature for several surfactants previously studied. Predictive models of toxicity is a handy tool for providing a risk assessment that can be useful to establish the toxicity range for each surfactant and the different test organisms in order to select efficient surfactants with a lower impact on the aquatic environment. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Identification of a locus controlling expression of luminescence genes in Vibrio harveyi.

    Science.gov (United States)

    Martin, M; Showalter, R; Silverman, M

    1989-05-01

    Mutagenesis with transposon mini-Mulac was used to identify loci containing genes for bioluminescence (lux) in the marine bacterium Vibrio harveyi. Transposon insertions which resulted in a Lux- phenotype were mapped to two unlinked regions of the genome. Region I contained the luxCDABE operon which was previously shown to encode the enzymes luciferase and fatty acid reductase, which are required for light production. The other locus, region II, which was identified for the first time in this study, appeared to have a regulatory function. In Northern blot analysis of mRNA from mutants with defects in this region, no transcription from the luxCDABE operon could be detected. Strains with transposon-generated lux::lacZ gene fusions were used to analyze control of the transcription of these regions. Expression of luminescence in the wild type was strongly influenced by the density of the culture, and in strains with the lacZ indicator gene coupled to the luxCDABE operon, beta-galactosidase synthesis was density dependent. So, transcription of this operon is responsive to a density-sensing mechanism. However, beta-galactosidase synthesis in strains with lacZ fused to the region II transcriptional unit did not respond to cell density. The organization and regulation of the lux genes of V. harveyi are discussed, particularly with regard to the contrasts observed with the lux system of the fish light-organ symbiont Vibrio fischeri.

  11. Prevalence of Vibrio vulnificus and Vibrio parahaemolyticus in the Maryland Coastal Bays

    Science.gov (United States)

    De Pascuale, V. O.

    2016-02-01

    The bacterial family of Vibrionaceae is indigenous in the marine estuarine environments such as the Maryland Coastal Bays. Vibrio vulnificus and Vibrio parahaemolyticus are both pathogenic bacteria. Understanding the distribution of Vibrio species is crucial because of the health concerns associated with the bacteria. The aim of this study was to evaluate the overall abundance of bacteria with a focus on Vibrio species in the Maryland Coastal Bays. Seawater samples were collected from 10 different sites that differ with regard to water quality. The total bacteria count (TBC) was determined by two methods: Total plate count and Epifluorescence microscopy. The most-probable-number (MPN) methodology was used to estimate the population of Vibrio parahaemolyticus and Vibrio vulnificus. In addition to the bacteriological analysis, the environmental parameters of temperature and salinity were measured using YSI 6600 multiparameter meter. The average total bacteria count was 2.21 log CFU ml-1. Vibrio vulnificus comprised 5% of the total bacteria count while Vibrio parahaemolyticus comprised only 2% of the total bacteria count. Vibrio vulnificus ranged from 0.30 to 2.48 log MPN ml-1 at the sites tested. Lower Vibrio parahaemolyticus count was observed at the sites with a range of 0.30 to 1.97 log MPN ml-1. There was no significant correlation between the environmental parameters and the Vibrio spp. Since both Vibrio vulnificus and Vibrio parahaemolyticus peak in the summer, there is a potential for a risk of wound infections and gastrointestinal illness based on this data.

  12. The ecology of Vibrio vulnificus, Vibrio cholerae, and Vibrio parahaemolyticus in North Carolina estuaries.

    Science.gov (United States)

    Blackwell, Karen Dyer; Oliver, James D

    2008-04-01

    While numerous studies have characterized the distribution and/or ecology of various pathogenic Vibrio spp., here we have simultaneously examined several estuarine sites for Vibrio vulnificus, V. cholerae, and V. parahaemolyticus. For a one year period, waters and sediment were monitored for the presence of these three pathogens at six different sites on the east coast of North Carolina in the United States. All three pathogens, identified using colony hybridization and PCR methods, occurred in these estuarine environments, although V. cholerae occurred only infrequently and at very low levels. Seventeen chemical, physical, and biological parameters were investigated, including salinity, water temperature, turbidity, dissolved oxygen, levels of various inorganic nutrients and dissolved organic carbon, as well as total vibrios, total coliforms, and E. coli. We found each of the Vibrio spp. in water and sediment to correlate to several of these environmental measurements, with water temperature and total Vibrio levels correlating highly (P<0.0001) with occurrence of the three pathogens. Thus, these two parameters may represent simple assays for characterizing the potential public health hazard of estuarine waters.

  13. Can Daphnia lumholtzi invade European lakes?

    Directory of Open Access Journals (Sweden)

    Meike Wittmann

    2013-03-01

    Full Text Available The cladoceran Daphnia lumholtzi is a subtropical and tropical zooplankter, and an invasive species in North America. Thus far, D. lumholtzi has not been detected in Europe. Here we investigated whether a hypothetical introduction to Europe could result in a successful invasion, either now or in the near future when facilitated by climate change. In laboratory experiments, we tested whether different clones of D. lumholtzi can invade a resident community consisting of native Daphnia from lake Klostersee, Germany, and how invasion success depends on temperature and the presence or absence of planktivorous fish. In some treatments, invasion success was consistently high, and D. lumholtzi reached densities similar to the native competitors by the end of the experiment. The presence of a planktivorous fish reduced the invasion success of D. lumholtzi, and a clone with an inducible defense against fish predation was a more successful invader than a permanently defended clone. Of the three temperatures tested in this study (15, 20, and 24 °C, invasion success was highest at 20 °C. To understand the competitive interaction between native and introduced Daphnia, we fit a Lotka-Volterra-type competition model to the population dynamics. Our experimental and modeling results suggest that D. lumholtzi can invade European lakes and can cause substantial declines in the population size of native Daphnia, with potential consequences for higher trophic levels.

  14. Vibrio Fischeri Symbiosis Gene Regulation.

    Science.gov (United States)

    1989-07-01

    is actually involved in the observed transcriptional negative autoregulation of lmxR expression, although the data suggest this. Cells in the above...Bioluminescence in the Marine Symbiotic Bacterium Vibriofischeri. Instituto de Investigaciones Bioquimicas , Fundacion Campomar, Buenos Aires, Argentina

  15. Evaluation of toxic and interactive toxic effects of three agrochemicals and copper using a battery of microbiotests.

    Science.gov (United States)

    Kungolos, A; Emmanouil, C; Tsiridis, V; Tsiropoulos, N

    2009-08-01

    Three commonly used test organisms of different trophic levels (Vibrio fischeri, Pseudokirchneriella subcapitata and Daphnia magna) were exposed to selected agrochemicals (fosthiazate, metalaxyl-M, imidacloprid) and copper, in single doses or in binary mixtures. The toxicity of each single compound varied up to two orders of magnitude, depending on the test species examined. V. fischeri was the most sensitive test organism regarding fosthiazate and metalaxyl-M, indicating an IC(50) value of 0.20 mg/L (0.17-0.25 mg/L) and 0.88 mg/L (0.35-1.57 mg/L), respectively. Imidacloprid was the least toxic compound, indicating an EC(50) value on D. magna of 64.6 mg/L (43.3-122.5 mg/L) and an IC(50) value on V. fischeri of 226 mg/L (159-322 mg/L), while for imidacloprid at a concentration of 1000 mg/L the effect on P. subcapitata was lower than 50%. Copper was the most toxic compound towards all test organisms exhibiting the highest toxic effect on P. subcapitata, with an IC(50) value of 0.05 mg/L (0.003-0.008 mg/L). The toxic effects of the binary mixtures have been compared to the theoretically expected effect, resulting from a simple mathematical model based on the theory of probabilities. The independent action model was used in order to predict the theoretically expected effect. The interactive effects were mostly antagonistic or additive, while in few cases (interactive effects of metalaxyl-M and copper on V. fischeri) a synergistic mode of action was observed for some concentration combinations. Experiments showed that interactive effects of chemicals may vary depending on the test species used as well as on the chemicals and their respective concentrations. Although most of the concentrations of chemicals tested in this study are higher than the ones usually found in natural environment, the evaluation of their interactive toxic effects using a battery of bioassays may comprise a useful tool for the estimation of the environmental hazard of chemicals.

  16. ORF Alignment: NC_006840 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... acetyltransferase [Vibrio fischeri ES114] ... Length = 146 ... Query: 2 ... VSIRTAEKTDLARIFDIETEAFGD...HGYPSFFIRQAFDCWADGLLVAKKEKETLGYVLQVP 61 ... VSIRTAEKTDLARIFDIETEAFGDHGYPSF...FIRQAFDCWADGLLVAKKEKETLGYVLQVP Sbjct: 1 ... VSIRTAEKTDLARIFDIETEAFGDHGYPSFFIRQAFDCWADGLLVAKKEKETLGYVLQVP 60 ... Q

  17. Comparison of Chemical Sensitivity of Fresh and Long-Stored Heat Resistant Neosartorya fischeri Environmental Isolates Using BIOLOG Phenotype MicroArray System.

    Directory of Open Access Journals (Sweden)

    Jacek Panek

    Full Text Available Spoilage of heat processed food and beverage by heat resistant fungi (HRF is a major problem for food industry in many countries. Neosartorya fischeri is the leading source of spoilage in thermally processed products. Its resistance to heat processing and toxigenicity makes studies about Neosartorya fischeri metabolism and chemical sensitivity essential. In this study chemical sensitivity of two environmental Neosartorya fischeri isolates were compared. One was isolated from canned apples in 1923 (DSM3700, the other from thermal processed strawberry product in 2012 (KC179765, used as long-stored and fresh isolate, respectively. The study was conducted using Biolog Phenotype MicroArray platforms of chemical sensitivity panel and traditional hole-plate method. The study allowed for obtaining data about Neosartorya fischeri growth inhibitors. The fresh isolate appeared to be much more resistant to chemical agents than the long-stored isolate. Based on phenotype microarray assay nitrogen compounds, toxic cations and membrane function compounds were the most effective in growth inhibition of N. fischeri isolates. According to the study zaragozic acid A, thallium(I acetate and sodium selenate were potent and promising N. fischeri oriented fungicides which was confirmed by both chemical sensitivity microplates panel and traditional hole-plate methods.

  18. ORF Alignment: NC_006840 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available endodeoxyribonuclease RuvC [Vibrio fischeri ES114] ... Length = 157 ... Query: 2 ... SIILGIDPGSRITGYGVIRQNGRHLQYLGSGCIRMS...EKELPGRLKQIYAGVSEIITQFQP 61 ... SIILGIDPGSRITGYGVIRQNGRHLQYLGSGCIRMS...EKELPGRLKQIYAGVSEIITQFQP Sbjct: 1 ... SIILGIDPGSRITGYGVIRQNGRHLQYLGSGCIRMSEKELPGRLKQIYAGVSEIITQFQP 6

  19. Microencapsulated Aliivibrio fischeri in Alginate Microspheres for Monitoring Heavy Metal Toxicity in Environmental Waters

    Directory of Open Access Journals (Sweden)

    Dedi Futra

    2014-12-01

    Full Text Available In this article a luminescence fiber optic biosensor for the microdetection of heavy metal toxicity in waters based on the marine bacterium Aliivibrio fischeri (A. fischeri encapsulated in alginate microspheres is described. Cu(II, Cd(II, Pb(II, Zn(II, Cr(VI, Co(II, Ni(II, Ag(I and Fe(II were selected as sample toxic heavy metal ions for evaluation of the performance of this toxicity microbiosensor. The loss of bioluminescence response from immobilized A. fischeri bacterial cells corresponds to changes in the toxicity levels. The inhibition of the luminescent biosensor response collected at excitation and emission wavelengths of 287 ± 2 nm and 487 ± 2 nm, respectively, was found to be reproducible and repeatable within the relative standard deviation (RSD range of 2.4–5.7% (n = 8. The toxicity biosensor based on alginate micropsheres exhibited a lower limit of detection (LOD for Cu(II (6.40 μg/L, Cd(II (1.56 μg/L, Pb(II (47 μg/L, Ag(I (18 μg/L than Zn(II (320 μg/L, Cr(VI (1,000 μg/L, Co(II (1700 μg/L, Ni(II (2800 μg/L, and Fe(III (3100 μg/L. Such LOD values are lower when compared with other previous reported whole cell toxicity biosensors using agar gel, agarose gel and cellulose membrane biomatrices used for the immobilization of bacterial cells. The A. fischeri bacteria microencapsulated in alginate biopolymer could maintain their metabolic activity for a prolonged period of up to six weeks without any noticeable changes in the bioluminescence response. The bioluminescent biosensor could also be used for the determination of antagonistic toxicity levels for toxicant mixtures. A comparison of the results obtained by atomic absorption spectroscopy (AAS and using the proposed luminescent A. fischeri-based biosensor suggests that the optical toxicity biosensor can be used for quantitative microdetermination of heavy metal toxicity in environmental water samples.

  20. Wastewater canal Vojlovica, industrial complex Pančevo, Serbia – preliminary ecotoxicological assessment of contaminated sediment

    Directory of Open Access Journals (Sweden)

    IVANA PLANOJEVIĆ

    2011-03-01

    Full Text Available Effluents collected from the industrial complex of Pančevo, Serbia (oil refinery, petrochemical plant, and fertilizer factory, are discharged into a wastewater canal entering the Danube River. In this study, which was focused on sediment assessment, a complex triad approach consisting of chemical analysis, sediment toxicity tests and macrozoobenthos community analysis was applied. In toxicity tests on sediment elutriates, the following responses were registered – stimulatory effect in algal bioassay, no effect in acute test with Daphnia magna, and low to moderate toxicity in the conventional Vibrio fischeri test. Moderate to high toxicities were recorded in solid phase tests on Myriophyllum aquaticum and V. fischeri. High content of Hg, certain PAHs and non-characterised sediment contaminants accumulated over years contribute not only to the registered toxicity, but also to the complete absence of macrozoobenthos. The obtained results proved that regularly measured conventional and priority pollutants are hardly ever the only toxic contaminants present in sediments. Toxicity tests, in particular the contact test, might guide towards a better selection of parameters to be regularly or occasionally monitored. In addition, complete sediment toxicity tests proved to be an appropriate method for assessing the bioavailability of the chemically detected contaminants. The analysis of the macrozoobenthos composition and structure as inevitable part of sediment risk assessment procedures integrates the effects of multiple stressors and gives a realistic insight into not only sediment contamination by toxic pollutants, but also the sediment status in general.

  1. Evaluation of toxicity and removal of color in textile effluent treated with electron beam; Avaliacao da toxicidade e remocao da cor de um efluente textil tratado com feixe de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Morais, Aline Viana de

    2015-07-01

    The textile industry is among the main activities Brazil, being relevant in number of jobs, quantity and diversity of products and mainly by the volume of water used in industrial processes and effluent generation. These effluents are complex mixtures which are characterized by the presence of dyes, surfactants, metal sequestering agents, salts and other potentially toxic chemicals for the aquatic biota. Considering the lack of adequate waste management to these treatments, new technologies are essential in highlighting the advanced oxidation processes such as ionizing radiation electron beam. This study includes the preparation of a standard textile effluent chemical laboratory and its treatment by electron beam from electron accelerator in order to reduce the toxicity and intense staining resulting from Cl. Blue 222 dye. The treatment caused a reduction in toxicity to exposed organisms with 34.55% efficiency for the Daphnia similis micro crustacean and 47.83% for Brachionus plicatilis rotifer at a dose of 2.5 kGy. The Vibrio fischeri bacteria obtained better results after treatment with a dose of 5 kGy showing 57.29% efficiency. Color reduction was greater than 90% at a dose of 2.5 kGy. This experiment has also carried out some preliminary tests on the sensitivity of the D. similis and V. fischeri organisms to exposure of some of the products used in this bleaching and dyeing and two water reuse simulations in new textile processing after the treating the effluent with electron beam. (author)

  2. Evaluation of toxicity and removal of color in textile effluent treated with electron beam

    International Nuclear Information System (INIS)

    Morais, Aline Viana de

    2015-01-01

    The textile industry is among the main activities Brazil, being relevant in number of jobs, quantity and diversity of products and mainly by the volume of water used in industrial processes and effluent generation. These effluents are complex mixtures which are characterized by the presence of dyes, surfactants, metal sequestering agents, salts and other potentially toxic chemicals for the aquatic biota. Considering the lack of adequate waste management to these treatments, new technologies are essential in highlighting the advanced oxidation processes such as ionizing radiation electron beam. This study includes the preparation of a standard textile effluent chemical laboratory and its treatment by electron beam from electron accelerator in order to reduce the toxicity and intense staining resulting from Cl. Blue 222 dye. The treatment caused a reduction in toxicity to exposed organisms with 34.55% efficiency for the Daphnia similis micro crustacean and 47.83% for Brachionus plicatilis rotifer at a dose of 2.5 kGy. The Vibrio fischeri bacteria obtained better results after treatment with a dose of 5 kGy showing 57.29% efficiency. Color reduction was greater than 90% at a dose of 2.5 kGy. This experiment has also carried out some preliminary tests on the sensitivity of the D. similis and V. fischeri organisms to exposure of some of the products used in this bleaching and dyeing and two water reuse simulations in new textile processing after the treating the effluent with electron beam. (author)

  3. Temperature-dependent effect of filamentous cyanobacteria on Daphnia magna life history traits

    Directory of Open Access Journals (Sweden)

    Piotr DAWIDOWICZ

    2011-08-01

    Full Text Available Filamentous cyanobacteria are unsuitable food for Daphnia due to their poor manageability, poor nutritional value and, in some cases, toxicity. As the strength of harmful effects of cyanobacteria on filter-feeding zooplankton is temperature dependent, the global warming scenarios for eutrophic lakes in temperate zone might include an escalated suppression of Daphnia populations caused by the presence of cyanobacterial filaments. To test this assumption, we conducted life-table experiments with four clones of Daphnia magna fed either a green alga Scenedesmus obliquus or a non-toxic strain of filamentous cyanobacteria Cylindrospermopsis raciborskii in two temperatures (20 °C and 24 °C. Key life history parameters of Daphnia, i.e., age and size at first reproduction, fecundity, and individual growth rate, were measured. Both food and temperature significantly affected Daphnia performance, however, the effect of interaction of these two factors was ambiguous and highly genotype-dependent. We conclude that the temperature increase within the studied range will not necessarily strengthen the suppression of Daphnia growth by filamentous cyanobacteria, but may affect clonal selection within population of Daphnia, thus possibly triggering microevolutionary changes within affected populations.

  4. Research in Biological and Medical Sciences Including Biochemistry, Communicable Disease and Immunology, Internal Medicine, Physiology, Psychiatry, Surgery, and Veterinary Medicine. Volume 1

    Science.gov (United States)

    1979-09-01

    Subcommittee on Taxonomy of Vibrios : V. cholera, V. parahemolyticus , V. anguillarum, V. fischeri, and V. costicola. In addition there are at least 20...alimentary canal of men and animals; some species are pathogenic for man and other vertebrates (fish). There are five species of Vibrio recognized by the...unspeciated strains that have been described. In addition to Vibrio there are four additional genera recognized in this family: Aeromonas, Plesiomonas

  5. Toxic potential of the emerging contaminant nicotine to the aquatic ecosystem.

    Science.gov (United States)

    Oropesa, Ana Lourdes; Floro, António Miguel; Palma, Patrícia

    2017-07-01

    Nicotine is a "life-style compound" widely consumed by human populations and, consequently, often found in surface waters. This fact presents a concern for possible effects in the aquatic ecosystems. The objective of this study was to assess the potential lethal and sublethal toxicity of nicotine in aquatic organisms from different trophic levels (Vibrio fischeri, Pseudokirchneriella subcapitata, Thamnocephalus platyurus, and Daphnia magna). The bioassays were performed by exposing the organisms to concentrations of nicotine in a range of 0.5-1000 μg/L. Results showed that nicotine, at tested concentration, was not acutely toxic to V. fischeri and T. platyurus. On the contrary, this substance exhibited toxicity to P. subcapitata and Daphnia magna. Thus, concentrations of nicotine of 100 and 200 μg/L promoted an inhibition in the growth of P. subcapitata. In addition, a concentration of 100 μg/L nicotine acted on the reproduction of the crustacean D. magna, by decreasing the number of juveniles produced by female. On the other hand, the results showed that concentrations equal to or greater than 10 μg/L induced the production of daphnids male offspring, which may indicate that nicotine is a weak juvenoid compound of the D. magna endocrine system. Furthermore, the result showed that concentrations tested of this chemical have the capacity to revert the effect of fenoxycarb, a strong juvenoid chemical insecticide. The results of the study revealed that nicotine can induce several changes in some of the most important key groups of the aquatic compartment, which can compromise, in a short time, the balance of aquatic ecosystem. Finally, a preliminary environmental risk assessment of this stimulant was performed from the highest measured concentration in surface water and the no observable effect concentration value in the most sensitive species, i.e., D. magna. This process revealed that nicotine can produce an important risk to aquatic organisms.

  6. The significance of nonviable eggs for Daphnia population dynamics

    NARCIS (Netherlands)

    Boersma, M.; Vijverberg, J.

    1995-01-01

    Egg mortality was studied in populations of Daphnia galeata, Daphnia cucullata, and the hybrid between these species. In Tjeukemeer, a shallow eutrophic lake in the Netherlands, egg mortality in daphnids manifested itself as an apparent increase in the frequency of eggs in the early developmental

  7. Organophosphorus insecticides: Toxic effects and bioanalytical tests for evaluating toxicity during degradation processes

    Directory of Open Access Journals (Sweden)

    Čolović Mirjana B.

    2013-01-01

    Full Text Available Organophosphorus insecticides have been the most applied group of insecticides for the last two decades. Their main toxic effects are related to irreversible inactivation of acetylcholinesterase (AChE. Actually, they covalently bind to serine OH group in the enzyme active site forming phosphorylated enzyme that cannot hydrolyze acetylcholine. Organophosphorus insecticides in the environment undergo the natural degradation pathway including mainly homogeneous and heterogeneous hydrolysis (especially at high pH generating non-inhibiting products. Additionally, thio organophosphates are easily oxidized by naturally present oxidants and UV light, forming more toxic and stable oxons. Thus, oxidative degradation procedures, generally referred as advanced oxidation processes (AOP, have been applied for their efficient removal from contaminated waters. The most applied bioassays to monitor the organophosphate toxicity i.e. the detoxification degree during AOP are Vibrio fischeri and AChE bioassays. Vibrio fischeri toxicity test exploits bioluminescence as the measure of luciferase activity of this marine bacterium, whereas AChE bioassay is based on AChE activity inhibition. Both bioanalytical techniques are rapid (several minutes, simple, sensitive and reproducible. Vibrio fischeri test seems to be a versatile indicator of toxic compounds generated in AOP for organophosphorus insecticides degradation. However, detection of neurotoxic AChE inhibitors, which can be formed in AOP of some organophosphates, requires AChE bioassays. Therefore, AChE toxicity test is more appropriate for monitoring the degradation processes of thio organophosphates, because more toxic oxo organophosphates might be formed and overlooked by Vibrio fischeri bioluminescence inhibition. In addition, during organophosphates removal by AOP, compounds with strong genotoxic potential may be formed, which cannot be detected by standard toxicity tests. For this reason, determination of

  8. Suspension of oysters reduces the populations of Vibrio parahaemolyticus and Vibrio vulnificus.

    Science.gov (United States)

    Cole, K M; Supan, J; Ramirez, A; Johnson, C N

    2015-09-01

    Vibrio parahaemolyticus (Vp) and Vibrio vulnificus (Vv) are associated with the consumption of raw oysters and cause illnesses ranging from simple gastroenteritis to life-threatening septicaemia. These halophilic bacteria are frequently found in marine and estuarine systems, accumulating within the tissues of a number of aquatic organisms and passing on to humans after consumption, through contaminated water, or via open wounds. As benthic organisms capable of filtering 40 gallons of water per hour, sediment is an important source of potentially pathogenic vibrios in oysters destined for raw consumption. This research used off-bottom oyster culture to reduce vibrio concentrations in oysters. Colony hybridization was used to enumerate Vp and Vv in bottom and suspended oysters. Vv and Vp concentrations were generally lower in oysters suspended off-bottom, and suspension decreased vibrio loads in oysters by an average of 13%. Suspension of oysters reduced vibrio concentrations. This study found that oyster suspension significantly reduced some populations of potentially pathogenic vibrios. These results indicate that oyster suspension could be a viable approach for preharvest treatment to reduce illness in consumers of raw oysters. © 2015 The Society for Applied Microbiology.

  9. Effects of diel vertical migration on ephippia production in Daphnia

    Directory of Open Access Journals (Sweden)

    Victor ALEKSEEV

    2004-09-01

    Full Text Available Fish presence in experimentally simulated temperature conditions (limno-towers led to diel vertical migration and resulted in a decrease of ephippia production in Daphnia pulicaria. Diel fluctuation of food, temperature and day length similar to those experienced by migrating Daphnia were tested in laboratory experiments with flow-through-systems. Daphnids were kept under these conditions for 15 days and the proportions of females producing an ephippium were determined. In addition, maturation time, survival to maturation, size of the first clutch and female dry weight (without eggs on day 15 were traced. The most important factor affecting ephippia production in migrating Daphnia was photoperiod change, and when mother and embryo are exposed to alternating light conditions, these are thought to have the effect on the mother of acting as a signal to stop ephippia production. Such effects might be explained by the different sensitiveness to light intensity in females carrying an embryo and an embryo itself in broods. Fish presence forced Daphnia to stay in low-light conditions during daytime hours, to avoid attacks by fish. The Daphnia were able to check light intensity constantly by short vertical jumps above a light-threshold that was confirmed experimentally in limno-towers. The dim conditions were possibly light enough for adults to check day length, but were too dark for embryos shaded by the mother's body. Food conditions played a relatively small role in the process, and no effects of temperature on ephippia production were found. As expected, food affected the size of the first clutch, and temperature controlled the time to maturation. Photoperiod had a marginally significant influence on the time to maturation in Daphnia. A hypothesis on the role of photoperiod as the key factor for Daphnia life cyclic recurrence and other seasonal adaptations is proposed.

  10. Swimming behaviour of Daphnia clones: differentiation through predator infochemicals

    NARCIS (Netherlands)

    Weber, A.; Van Noordwijk, A.J.

    2002-01-01

    We studied variation in small-scale swimming behavior (SSB) in four clones of Daphnia galeata (water flea) in response to predator infochemicals. The aim of this study was 3-fold. First, we tested for differences in SSB in Daphnia; second, we examined the potential of differences in SSB to explain

  11. Genes encoding the Vibrio harveyi haemolysin (VHH)/thermolabile haemolysin (TLH) are widespread in Vibrios%VHH/TLH溶血素基因在海洋弧菌中分布的研究

    Institute of Scientific and Technical Information of China (English)

    王淑娴; 张晓华; 钟英斌; 孙铂光; 陈吉祥

    2007-01-01

    deduced amino acid sequences are up to 85.6%), is a putative virulence factor to marine cultured fish. A VHH probe, which is specific to V. harveyi vhhA haemolysin gene, was used to screen EcoR Ⅰ digests of total DNA from 57 vibrio strains, including 26 vibrio type strains, 20 V. harveyi isolates and 11 V. parahaemolyticus isolates. As a result, 1 strong hybridisation band was detected in 13 type strains, including 2 of Vibrio alginolyticus , 2 of V. harveyi , and 1 strain each of Grimontia hollisae , V. campbellii , V. cincinnatiensis , V. fischeri , V. mimicus , V.natriegens, V. parahaemolyticus, V. proteolyticus and V. logei. Also, 1 weak band was detected in 6 type strains, including V.anguillarum, V. aestuarianus, Photobacterium damselae subsp. damselae, V. fluvialis, V. furnissii and V. vulnificus. There was not any hybridization signal in other type strains. Also, vhh/tlh was present in all isolates of V. harveyi and V. parahaemolyticus. Moreover, 3 isolates of V. harveyi, i.e. VIB 645, VIB 648 and SF1, had duplicated vhh genes. The data indicates that vhh/tlh is widespread in vibrios,especially in V. harveyi related species and V. fischeri related species. To support this conclusion, the vhh/tlh homologue genes in V.anguillarum VIB 72, V. campbellii VIB 285, V. natriegens VIB 299 and V. harveyi VIB 647 were cloned and sequenced, and the deduced amino acid sequences showed high degree of identities to VHH (67% ~ 99% ) and TLH haemolysin (69% ~ 91% ). This study will help us to identify the role of vhh/tlh haemolysin gene in the pathogenicity of vibrios.

  12. White shrimp (Litopenaeus vannamei) recombinant lysozyme has antibacterial activity against Gram negative bacteria: Vibrio alginolyticus, Vibrio parahemolyticus and Vibrio cholerae.

    Science.gov (United States)

    de-la-Re-Vega, Enrique; García-Galaz, Alfonso; Díaz-Cinco, Martha E; Sotelo-Mundo, Rogerio R

    2006-03-01

    C-type lysozyme has been described as an antibacterial component of the shrimp innate defence system. We determined quantitatively the antibacterial activity of white shrimp (Litopenaeus vannamei) recombinant lysozyme against three Gram negative bacteria: Vibrio alginolyticus, Vibrio parahemolyticus and Vibrio cholerae, using a turbidimetric assay with live bacteria and differential bacterial viable count after interaction with the protein. In conclusion, the antibacterial activity of recombinant shrimp lysozyme against Vibrio sp. is at least equal to the values against the Gram positive M. luteus and more active against the shrimp pathogens V. alginolyticus and V. parahemolyticus.

  13. Responses of alkaline phosphatase activity to phosphorus stress in Daphnia magna.

    Science.gov (United States)

    McCarthy, S D S; Rafferty, S P; Frost, P C

    2010-01-15

    We examined how alkaline phosphatase (AP) activity within the bodies and in the materials released by the crustacean Daphnia magna responds to variable algal food phosphorus (P)-content. We found that Daphnia eating P-poor food (C:P approximately 700) had significantly higher AP activity in their bodies on a mass-specific basis compared with individuals eating P-rich food (C:P approximately 100). This dietary P effect on AP activity was not altered by Daphnia starvation but was partially related to differences in the P concentration of animal body homogenates. By contrast, poor P-nutrition of Daphnia lowered AP activity in released materials compared with that measured from their P-sufficient conspecifics. Moreover, AP activity in Daphnia release was lowest in animals consuming P-poor food for longer time periods. Our results support the hypothesis that AP activity increases inside P-limited Daphnia as a mechanism to increase P-acquisition and retention from ingested algae in these nutritionally stressed animals. The lower level of AP activity present in the water of P-deprived animals could reflect a change from largely free to membrane-bound AP isotypes in the digestive tracts of P-starved animals or a decrease in the shedding of membrane-anchored AP from their intestinal lining. These results supplement accumulating evidence that P-poor algal food reduces the dietary mineral P available to Daphnia. In addition, animal body AP activity measurements, with some refinement, may prove useful as an in situ indicator of P-stress in aquatic consumers.

  14. Vibrio spp. ISOLATED FROM SHRIMPS AND WATER FROM A MARINE FARM IN PERNAMBUCO, BRAZIL Víbrios en el agua y en las gambas del mar (Litopenaeus vannamei, Boone, 1931 cultivado en Pernambuco Vibrio spp. ISOLADOS DE CAMARÃO E ÁGUA DE CULTIVO DE FAZENDA MARINHA EM PERNAMBUCO

    Directory of Open Access Journals (Sweden)

    Carlos André Bezerra Alves

    2009-12-01

    Full Text Available

    Water and shrimp samples were collected monthly, during all cultivation phases, in three located farms at Pernambuco coast, on winter and summer, for Vibrio spp. quantification and identification. The counting’s were correlated, through mathematical models (P<0.05, with the variables season, water biochemical parameters, wet mount, histopathology exam, toxins presence and handling techniques used. Just the variable cultivation time interfered at total counting of Vibrio spp. in all samples were obtained countings that varied 0.1x 10 to 6.2 x 103 UFC/mL in water, of 7.0 x 10 to 8.2 x 105 UFC/g in powder-larva, of 1.1 x 10 to 1.1 x 105 UFC/mL in hemolymph and of 2.5 x 102 to 1.1 x 106UFC/g in hepatopancreas. The species V. mediterranei (1%, V. mimicus (1.25%, V. fischeri (4.25%, V. cincinnatiensis (4.25%, V. metschnikovii (4.25%, V. proteolyticus (5.5%, V. harveyi (5.5%, V. hollisae (5.5%, V. carchariae (7%, V. vulnificus (8.5%, V. damsela (8.5%, V. parahaemolyticus (13%, V. fluvialis (15%, V. anguillarum (16.5% were identified. It is concluded that the Vibrionaceae load increases proportionally with cultivation time, due to the organic matter increment, what can turn the susceptible animals to the infection for vibrios.

    KEY WORD: Vibrionaceae, Vibrio spp., shrimp and pond water.
    El agua y muestras de la gamba eran la publicación mensual reunido, durante todas las fases del cultivo, en tres granjas localizadas a la costa de Pernambuco, en invierno y verano, para la cuantificación e identificación el de Vibrio spp.. El contando fueron puestos en correlación, a través de los modelos matemáticos (P <0,05, con la estación de las variables, agua que los parámetros bioquímicos, montaña mojada, examen del histopatologia, presencia de las toxinas y técnicas manejando usaron. Simplemente el tiempo del cultivo inconstante interfirió a total que

  15. Predatory bacteria as natural modulators of Vibrio parahaemolyticus and Vibrio vulnificus in seawater and oysters

    Science.gov (United States)

    This study shows that naturally occurring Vibrio predatory bacteria (VPB) exert a major role in controlling pathogenic vibrios in seawater and shellfish. The growth and persistence of Vibrio parahaemolyticus (Vp) and Vibrio vulnificus (Vv) were assessed in natural seawater and in the Eastern oyster...

  16. Bacterial bioluminescence regulates expression of a host cryptochrome gene in the squid-Vibrio symbiosis.

    Science.gov (United States)

    Heath-Heckman, Elizabeth A C; Peyer, Suzanne M; Whistler, Cheryl A; Apicella, Michael A; Goldman, William E; McFall-Ngai, Margaret J

    2013-04-02

    The symbiosis between the squid Euprymna scolopes and its luminous symbiont, Vibrio fischeri, is characterized by daily transcriptional rhythms in both partners and daily fluctuations in symbiont luminescence. In this study, we sought to determine whether symbionts affect host transcriptional rhythms. We identified two transcripts in host tissues (E. scolopes cry1 [escry1] and escry2) that encode cryptochromes, proteins that influence circadian rhythms in other systems. Both genes cycled daily in the head of the squid, with a pattern similar to that of other animals, in which expression of certain cry genes is entrained by environmental light. In contrast, escry1 expression cycled in the symbiont-colonized light organ with 8-fold upregulation coincident with the rhythms of bacterial luminescence, which are offset from the day/night light regime. Colonization of the juvenile light organ by symbionts was required for induction of escry1 cycling. Further, analysis with a mutant strain defective in light production showed that symbiont luminescence is essential for cycling of escry1; this defect could be complemented by presentation of exogenous blue light. However, blue-light exposure alone did not induce cycling in nonsymbiotic animals, but addition of molecules of the symbiont cell envelope to light-exposed animals did recover significant cycling activity, showing that light acts in synergy with other symbiont features to induce cycling. While symbiont luminescence may be a character specific to rhythms of the squid-vibrio association, resident microbial partners could similarly influence well-documented daily rhythms in other systems, such as the mammalian gut.

  17. Two New Alkaloids from a Marine-derived Fungus Neosartorya fischeri

    Directory of Open Access Journals (Sweden)

    Bin Wu

    2015-04-01

    Full Text Available Investigation of EtOAc extract from the fermentation broth of the fungus Neosartorya fischeri led to the isolation of two novel alkaloids and one known compound with antitumor activity against HL-60 cell lines. Their structures were elucidated mainly by NMR and HR-TOF-MS, as well as on comparison with the reported data.

  18. Transcriptional basis of phenotypic plasticity in Daphnia pulex

    OpenAIRE

    Spanier, Katina

    2009-01-01

    The planktonic microcrustacean Daphnia pulex is among the best-studied animals in ecological, toxicological, and evolutionary research. The genome of D. pulex has recently been sequenced as the rst crustacean genome by the Daphnia Genomics Consortium (DGC), which opens new doors for interpreting and using the vast knowledge about this model organism from a genomic perspective. From an evolutionary ecological point of view, D. pulex is particularly interesting due to its ability to respo...

  19. Hyperprogesteronemia in response to Vitex fischeri consumption in wild chimpanzees (Pan troglodytes schweinfurthii).

    Science.gov (United States)

    Emery Thompson, Melissa; Wilson, Michael L; Gobbo, Grace; Muller, Martin N; Pusey, Anne E

    2008-11-01

    Chimpanzees in Gombe National Park consume fruits of Vitex fischeri during a short annual fruiting season. This fruit species is a member of a genus widely studied for phytoestrogen composition and varied physiological effects. One particularly well-studied species, V. agnus-castus, is noted for its documented effects on female reproductive function, evidenced in increased progesterone levels and consequent regulation of luteal function. We examined reproductive hormone levels in both male and female chimpanzees during a 6-week period of intense V. fischeri consumption. V. fischeri consumption was associated with an abrupt and dramatic increase in urinary progesterone levels of female chimpanzees to levels far exceeding the normal range of variation. Female estrogen levels were not significantly impacted, nor were male testosterone levels. These are some of the first data indicating that phytochemicals in the natural diet of a primate can have significant impacts on the endocrine system, though the fluctuating nature of chimpanzee diet and reproductive function does not allow us to determine whether the effects observed during this short period had a broader positive or negative impact on female fertility. Given the widespread use of various Vitex species by African primates and the as-yet-undescribed phytochemical properties of these species, we predict that our observations may be indicative of a broader phenomenon. Copyright 2008 Wiley-Liss, Inc.

  20. The influence of bacteria-dominated diets on Daphnia magna somatic growth, reproduction, and lipid composition.

    Science.gov (United States)

    Taipale, Sami J; Brett, Michael T; Pulkkinen, Katja; Kainz, Martin J

    2012-10-01

    We explored how dietary bacteria affect the life history traits and biochemical composition of Daphnia magna, using three bacteria taxa with very different lipid composition. Our objectives were to (1) examine whether and how bacteria-dominated diets affect Daphnia survival, growth, and fecundity, (2) see whether bacteria-specific fatty acid (FA) biomarkers accrued in Daphnia lipids, and (3) explore the quantitative relationship between bacteria availability in Daphnia diets and the amounts of bacterial FA in their lipids. Daphnia were fed monospecific and mixed diets of heterotrophic (Micrococcus luteus) or methanotrophic bacteria (Methylomonas methanica and Methylosinus trichosporium) and two phytoplankton species (Cryptomonas ozolinii and Scenedesmus obliquus). Daphnia neonates fed pure bacteria diets died after 6-12 days and produced no viable offspring, whereas those fed pure phytoplankton diets had high survival, growth, and reproduction success. Daphnia fed a mixed diet with 80% M. luteus and 20% of either phytoplankton had high somatic growth, but low reproduction. Conversely, Daphnia fed mixed diets including 80% of either methane-oxidizing bacteria and 20% Cryptomonas had high reproduction rates, but low somatic growth. All Daphnia fed mixed bacteria and phytoplankton diets had strong evidence of both bacteria- and phytoplankton-specific FA biomarkers in their lipids. FA mixing model calculations indicated that Daphnia that received 80% of their carbon from bacteria assimilated 46 ± 25% of their FA from this source. A bacteria-phytoplankton gradient experiment showed a strong positive correlation between the proportions of the bacterial FA in the Daphnia and their diet, indicating that bacterial utilization can be traced in this keystone consumer using FA biomarkers. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  1. Population genetics, ecogenomics and physiological mechanisms of adaptation of Daphnia to cyanobacteria

    OpenAIRE

    Küster, Christian

    2012-01-01

    In many freshwater ecosystems Daphnia represent both, an important herbivorous grazer of phytoplankton and a major prey of planktivorous fish and invertebrate predators. Thus, Daphnia provide an important link for the transfer of energy and carbon from primary producers to higher trophic levels. In eutrophic lakes this transfer is often reduced by the occurrence of cyanobacteria that are known for their low food quality for Daphnia: Cyanobacteria lack essential sterols and polyunsaturated fat...

  2. 4,5-Di-O-Caffeoylquinic Acid from Ligularia fischeri Suppresses Inflammatory Responses Through TRPV1 Activation.

    Science.gov (United States)

    Kim, Yiseul; Kim, Jung Tae; Park, Joonwoo; Son, Hee Jin; Kim, Eun-Young; Lee, Young Joo; Rhyu, Mee-Ra

    2017-10-01

    Ligularia fischeri (Ledeb.) Turcz., a perennial plant native to northeastern Asia, has long been used as folk remedies for the alleviation of inflammatory symptoms. We investigated whether the extract of L. fischeri (LFEx) and caffeoylquinic acid (CQA) derivatives, the pharmacologically active ingredients identified from L. fischeri, regulate inflammation via a transient receptor potential vanilloid 1 (TRPV1)-mediated pathway. Changes in intracellular Ca 2+ levels to the LFEx and trans-5-O-CQA, 3,4-di-O-CQA, 3,5-di-O-CQA, and 4,5-di-O-CQA were monitored in TRPV1-expressing human embryonic kidney cell HEK 293T. LFEx and 4,5-di-O-CQA (EC 50  = 69.34 ± 1.12 μM) activated TRPV1, and these activations were significantly inhibited by ruthenium red, a general blocker of TRP channels, and capsazepine, a specific antagonist of TRPV1. 4,5-Di-O-CQA has been determined having antiinflammatory effect under hypoxic conditions by detecting the expression of cyclooxygenase-2 (COX-2), a representative inflammatory marker, and cellular migration in human pulmonary epithelial A549 cells. 4,5-Di-O-CQA suppressed COX-2 expression and cell migration, and this inhibition was countered by co-treatment with capsazepine. This study provides evidence that L. fischeri is selective to inflammatory responses via a TRPV1-mediated pathway, and 4,5-di-O-CQA might play a key role to create these effects. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  3. Production of L-Asparaginase by the marine luminous bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.; Chandramohan, D.

    Fortythree strains of luminous bacteria, belonging to 4 species, (Vibrio harveyi, V. fischeri, Photobacterium leiognathi and P. phosphoreum) isolated from different marine samples, were examined for the production of L-asparaginase. Presence...

  4. Evaluation of MWNT toxic effects on daphnia and zebrafish embryos

    Energy Technology Data Exchange (ETDEWEB)

    Olasagasti, Maider; Rainieri, Sandra [AZTI-TECNALIA, Parque Tecnologico de Bizkaia 609, 48160 Derio (Spain)], E-mail: srainieri@azti.es; Alvarez, Noelia; Vera, Carolina [INASMET-TECNALIA, Mikeletegi pasealekua, 2, Parque Tecnologico, 20009 San Sebastian (Spain)

    2009-05-01

    Organisms of daphnia (Daphnia magna) and zebrafish (Danio rerio) embryos were exposed to a range of different concentrations of COOH-functionalized MWCNT suspended in an aqueous solution of Tween 20. Immobilization of daphnia and growth retardation, inhibition and malformation of zebrafish embryos were the endpoints tested after 24 and 48 hours. Immobilization of daphnia could be observed from 3 to 16 ppm and an increasing mortality of zebrafish embryo was detected at all the concentration tested. To identify more subtle toxic effects, we took advantage of the extensive information available on the zebrafish genome and monitored by RT-PCR the expression patterns of different zebrafish genes that could act as toxicity bio-markers. At some of the concentrations tested, changes in the expression profiles of the genes examined were detected. Our results suggest that MWCNT could potentially represent a risk to human health and environment, therefore a wider range of concentrations and further testing of this molecules should be carried out to define possible limitations in their use.

  5. Rapid proliferation of Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae during freshwater flash floods in French Mediterranean coastal lagoons.

    Science.gov (United States)

    Esteves, Kevin; Hervio-Heath, Dominique; Mosser, Thomas; Rodier, Claire; Tournoud, Marie-George; Jumas-Bilak, Estelle; Colwell, Rita R; Monfort, Patrick

    2015-11-01

    Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae of the non-O1/non-O139 serotype are present in coastal lagoons of southern France. In these Mediterranean regions, the rivers have long low-flow periods followed by short-duration or flash floods during and after heavy intense rainstorms, particularly at the end of the summer and in autumn. These floods bring large volumes of freshwater into the lagoons, reducing their salinity. Water temperatures recorded during sampling (15 to 24°C) were favorable for the presence and multiplication of vibrios. In autumn 2011, before heavy rainfalls and flash floods, salinities ranged from 31.4 to 36.1‰ and concentrations of V. parahaemolyticus, V. vulnificus, and V. cholerae varied from 0 to 1.5 × 10(3) most probable number (MPN)/liter, 0.7 to 2.1 × 10(3) MPN/liter, and 0 to 93 MPN/liter, respectively. Following heavy rainstorms that generated severe flash flooding and heavy discharge of freshwater, salinity decreased, reaching 2.2 to 16.4‰ within 15 days, depending on the site, with a concomitant increase in Vibrio concentration to ca. 10(4) MPN/liter. The highest concentrations were reached with salinities between 10 and 20‰ for V. parahaemolyticus, 10 and 15‰ for V. vulnificus, and 5 and 12‰ for V. cholerae. Thus, an abrupt decrease in salinity caused by heavy rainfall and major flooding favored growth of human-pathogenic Vibrio spp. and their proliferation in the Languedocian lagoons. Based on these results, it is recommended that temperature and salinity monitoring be done to predict the presence of these Vibrio spp. in shellfish-harvesting areas of the lagoons. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Sensitivity of the vibrios to ultraviolet-radiation

    International Nuclear Information System (INIS)

    Banerjee, S.K.; Chatterjee, S.N.

    1977-01-01

    The ultraviolet-inactivation kinetics of a number of strains of Vibrio cholerae (classical), Vibrio cholerae (el tor), NAG vibrios and Vibrio parahaemolyticus were investigated. Statistical analyses revealed significant differences between any two of the four types of vibrio in respect of their sensitivity to U.V. (author)

  7. Microcystis aeruginosa strengthens the advantage of Daphnia similoides in competition with Moina micrura.

    Science.gov (United States)

    Tang, Hengxing; Hou, Xinying; Xue, Xiaofeng; Chen, Rui; Zhu, Xuexia; Huang, Yuan; Chen, Yafen

    2017-08-31

    Microcystis blooms are generally associated with zooplankton shifts by disturbing interspecific relationships. The influence of Microcystis on competitive dominance by different sized zooplanktons showed species-specific dependence. We evaluated the competitive responses of small Moina micrura and large Daphnia similoides to the presence of Microcystis using mixed diets comprising 0%, 20%, and 35% of toxic M. aeruginosa, and the rest of green alga Chlorella pyrenoidosa. No competitive exclusion occurred for the two species under the tested diet combinations. In the absence of M. aeruginosa, the biomasses of the two cladocerans were decreased by the competition between them. However, the Daphnia was less inhibited with the higher biomass, suggesting the competitive dominance of Daphnia. M. aeruginosa treatment suppressed the population growths of the two cladocerans, with the reduced carrying capacities. Nonetheless, the population inhibition of Daphnia by competition was alleviated by the increased Microcystis proportion in diet. As a result, the competitive advantage of Daphnia became more pronounced, as indicated by the higher Daphnia: Moina biomass ratio with increased Microcystis proportions. These results suggested that M. aeruginosa strengthens the advantage of D. similoides in competition with M. micrura, which contributes to the diversified zooplankton shifts observed in fields during cyanobacteria blooms.

  8. Light organ symbioses in fishes.

    Science.gov (United States)

    Haygood, M G

    1993-01-01

    Most bioluminescent fishes are self-luminescent, but a substantial minority of bioluminescent teleosts produce light that is due to symbiotic luminous bacteria housed in elaborate light organs. The majority of symbiotically bioluminescent fishes (ten families in five orders) harbors common free-living species of marine luminous bacteria: Photobacterium phosphoreum, P. leiognathi, and P. fischeri (= Vibrio fischeri). Others, associated with the beryciform family Anomalopidae and nine families in the lophiiform suborder Ceratioidei, have apparently obligate symbionts that have recently been identified by small subunit (16S) rRNA analysis as new groups within the genus Vibrio. This article summarizes what is currently known about relationships between light organ symbionts and their hosts, including characteristics of light organ environments, physiology of light organ symbionts, and the evolution of light organ symbionts and their associations.

  9. Ingestion of microcystins by Daphnia: Intestinal uptake and toxic effects

    DEFF Research Database (Denmark)

    Rohrlack, T.; Christoffersen, K.; Dittmann, E.

    2005-01-01

    We investigated the intestinal uptake and adverse effects of microcystins ingested with Microcystis on Daphnia galeata. The gut structure, blood microcystin concentration, appearance, and movements of Daphnia fed Microcystis PCC 7806 or a microcystin-deficient PCC 7806 mutant were monitored over ...

  10. Toxicity of tetramethylammonium hydroxide to aquatic organisms and its synergistic action with potassium iodide.

    Science.gov (United States)

    Mori, Izumi C; Arias-Barreiro, Carlos R; Koutsaftis, Apostolos; Ogo, Atsushi; Kawano, Tomonori; Yoshizuka, Kazuharu; Inayat-Hussain, Salmaan H; Aoyama, Isao

    2015-02-01

    The aquatic ecotoxicity of chemicals involved in the manufacturing process of thin film transistor liquid crystal displays was assessed with a battery of four selected acute toxicity bioassays. We focused on tetramethylammonium hydroxide (TMAH, CAS No. 75-59-2), a widely utilized etchant. The toxicity of TMAH was low when tested in the 72 h-algal growth inhibition test (Pseudokirchneriellia subcapitata, EC50=360 mg L(-1)) and the Microtox® test (Vibrio fischeri, IC50=6.4 g L(-1)). In contrast, the 24h-microcrustacean immobilization and the 96 h-fish mortality tests showed relatively higher toxicity (Daphnia magna, EC50=32 mg L(-1) and Oryzias latipes, LC50=154 mg L(-1)). Isobologram and mixture toxicity index analyses revealed apparent synergism of the mixture of TMAH and potassium iodide when examined with the D. magna immobilization test. The synergistic action was unique to iodide over other halide salts i.e. fluoride, chloride and bromide. Quaternary ammonium ions with longer alkyl chains such as tetraethylammonium and tetrabutylammonium were more toxic than TMAH in the D. magna immobilization test. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Electron beam irradiation of textile effluents and non-ionic ethoxylated surfactant for toxicity and color removal

    Energy Technology Data Exchange (ETDEWEB)

    Sole, Stephanie V. Del; Garcia, Vanessa S.G.; Boiani, Nathalia F.; Rosa, Jorge M.; Andrade e Silva, Leonardo G. de; Borrely, Sueli I., E-mail: vanessagranadeiro@gmail.com, E-mail: steh.vdsole@gmail.com, E-mail: jotarosa@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); SENAI, Faculdade de Tecnologia Antoine Skaf, Sao Paulo, SP (Brazil)

    2017-11-01

    Textile industry has an expressive scenario in the world economy and Brazil is the 5{sup th} in the textile production. By 2015, Brazilian textile production represented US $ 39.3 billion, accounting for more than 1.8 million tons of fabric (ABIT, 2017). The effluents from textile industry are highlighted by quantity of wastewater discharged and variety of substances (dyes, bleaching agents, surfactants, salts, acids, among others). Such compounds often prove to be toxic to aquatic biota. This present study aims to assess toxicity of whole effluents, before and after irradiation (by electron beam accelerator, EBI). In addition, the reduction of the effluent color after irradiation is also very important. Daphnia similis and Vibrio fischeri were the biological systems applied for toxicity evaluations. Previous results demonstrated the surfactant as the main toxic compound, in the untreated and irradiated forms, EC 50 = 0.44 ppm ± 0.02 (untreated); EC 50 = 0.46 % ± 0.07 (irradiated). The irradiation was effective in reducing the color of the effluent, starting from 0.5 kGy. EB radiation may be proposed as an alternative treatment for the final effluent from textile processing, mainly for reuse purposes. (author)

  12. Electron beam irradiation of textile effluents and non-ionic ethoxylated surfactant for toxicity and color removal

    International Nuclear Information System (INIS)

    Sole, Stephanie V. Del; Garcia, Vanessa S.G.; Boiani, Nathalia F.; Rosa, Jorge M.; Andrade e Silva, Leonardo G. de; Borrely, Sueli I.

    2017-01-01

    Textile industry has an expressive scenario in the world economy and Brazil is the 5"t"h in the textile production. By 2015, Brazilian textile production represented US $ 39.3 billion, accounting for more than 1.8 million tons of fabric (ABIT, 2017). The effluents from textile industry are highlighted by quantity of wastewater discharged and variety of substances (dyes, bleaching agents, surfactants, salts, acids, among others). Such compounds often prove to be toxic to aquatic biota. This present study aims to assess toxicity of whole effluents, before and after irradiation (by electron beam accelerator, EBI). In addition, the reduction of the effluent color after irradiation is also very important. Daphnia similis and Vibrio fischeri were the biological systems applied for toxicity evaluations. Previous results demonstrated the surfactant as the main toxic compound, in the untreated and irradiated forms, EC 50 = 0.44 ppm ± 0.02 (untreated); EC 50 = 0.46 % ± 0.07 (irradiated). The irradiation was effective in reducing the color of the effluent, starting from 0.5 kGy. EB radiation may be proposed as an alternative treatment for the final effluent from textile processing, mainly for reuse purposes. (author)

  13. Peracetic acid for secondary effluent disinfection: a comprehensive performance assessment.

    Science.gov (United States)

    Antonelli, M; Turolla, A; Mezzanotte, V; Nurizzo, C

    2013-01-01

    The paper is a review of previous research on secondary effluent disinfection by peracetic acid (PAA) integrated with new data about the effect of a preliminary flash-mixing step. The process was studied at bench and pilot scale to assess its performance for discharge in surface water and agricultural reuse (target microorganisms: Escherichia coli and faecal coliform bacteria). The purposes of the research were: (1) determining PAA decay and disinfection kinetics as a function of operating parameters, (2) evaluating PAA suitability as a disinfectant, (3) assessing long-term disinfection efficiency, (4) investigating disinfected effluent biological toxicity on some aquatic indicator organisms (Vibrio fischeri, Daphnia magna and Selenastrum capricornutum), (5) comparing PAA with conventional disinfectants (sodium hypochlorite, UV irradiation). PAA disinfection was capable of complying with Italian regulations on reuse (10 CFU/100 mL for E. coli) and was competitive with benchmarks. No regrowth phenomena were observed, as long as needed for agricultural reuse (29 h after disinfection), even at negligible concentrations of residual disinfectant. The toxic effect of PAA on the aquatic environment was due to the residual disinfectant in the water, rather than to chemical modification of the effluent.

  14. Hydroxyl radical induced degradation of ibuprofen

    Energy Technology Data Exchange (ETDEWEB)

    Illés, Erzsébet, E-mail: erzsebet.illes@chem.u-szeged.hu [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary); Takács, Erzsébet [Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary); Dombi, András [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Gajda-Schrantz, Krisztina [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Department of Inorganic and Analytical Chemistry, University of Szeged, Szeged (Hungary); EMPA, Laboratory for High Performance Ceramics, Duebendorf (Switzerland); Rácz, Gergely; Gonter, Katalin; Wojnárovits, László [Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary)

    2013-03-01

    Pulse radiolysis experiments were used to characterize the intermediates formed from ibuprofen during electron beam irradiation in a solution of 0.1 mmol dm{sup −3}. For end product characterization {sup 60}Co γ-irradiation was used and the samples were evaluated either by taking their UV–vis spectra or by HPLC with UV or MS detection. The reactions of {sup ·}OH resulted in hydroxycyclohexadienyl type radical intermediates. The intermediates produced in further reactions hydroxylated the derivatives of ibuprofen as final products. The hydrated electron attacked the carboxyl group. Ibuprofen degradation is more efficient under oxidative conditions than under reductive conditions. The ecotoxicity of the solution was monitored by Daphnia magna standard microbiotest and Vibrio fischeri luminescent bacteria test. The toxic effect of the aerated ibuprofen solution first increased upon irradiation indicating a higher toxicity of the first degradation products, then decreased with increasing absorbed dose. Highlights: ► In hydroxyl radical attack on the ring mainly hydroxylated products form ► The hydrated electron attacks the carboxyl group. ► Oxidative conditions are more effective in ibuprofen decomposition than reductive. ► Ecotoxicity of ibuprofen solution first increases then decreases with irradiation.

  15. Hydroxyl radical induced degradation of ibuprofen

    International Nuclear Information System (INIS)

    Illés, Erzsébet; Takács, Erzsébet; Dombi, András; Gajda-Schrantz, Krisztina; Rácz, Gergely; Gonter, Katalin; Wojnárovits, László

    2013-01-01

    Pulse radiolysis experiments were used to characterize the intermediates formed from ibuprofen during electron beam irradiation in a solution of 0.1 mmol dm −3 . For end product characterization 60 Co γ-irradiation was used and the samples were evaluated either by taking their UV–vis spectra or by HPLC with UV or MS detection. The reactions of · OH resulted in hydroxycyclohexadienyl type radical intermediates. The intermediates produced in further reactions hydroxylated the derivatives of ibuprofen as final products. The hydrated electron attacked the carboxyl group. Ibuprofen degradation is more efficient under oxidative conditions than under reductive conditions. The ecotoxicity of the solution was monitored by Daphnia magna standard microbiotest and Vibrio fischeri luminescent bacteria test. The toxic effect of the aerated ibuprofen solution first increased upon irradiation indicating a higher toxicity of the first degradation products, then decreased with increasing absorbed dose. Highlights: ► In hydroxyl radical attack on the ring mainly hydroxylated products form ► The hydrated electron attacks the carboxyl group. ► Oxidative conditions are more effective in ibuprofen decomposition than reductive. ► Ecotoxicity of ibuprofen solution first increases then decreases with irradiation

  16. A decrease in bulk water and mannitol and accumulation of trehalose and trehalose-based oligosaccharides define a two-stage maturation process towards extreme stress resistance in ascospores of Neosartorya fischeri (Aspergillus fischeri)

    NARCIS (Netherlands)

    Wyatt, Timon T; Golovina, Elena A; van Leeuwen, Richard; Hallsworth, John E; Wösten, Han A B; Dijksterhuis, Jan

    Fungal propagules survive stresses better than vegetative cells. Neosartorya fischeri, an Aspergillus teleomorph, forms ascospores that survive high temperatures or drying followed by heat. Not much is known about maturation and development of extreme stress resistance in fungal cells. This study

  17. Hatchery mortalities of larval oysters caused by Vibrio tubiashii and Vibrio coralliilyticus

    Science.gov (United States)

    Hatchery production of bivalve shellfish has been hampered by the occasional presence of opportunistic pathogens, particularly Vibrio coralliilyticus and Vibrio tubiashii. The present study reports the results of several avenues of research to better define these pathogens and the roles they play i...

  18. A spontaneous mutant of microcystin biosynthesis: genetic characterization and effect on Daphnia

    DEFF Research Database (Denmark)

    Kabernick, M.; Rohrlack, T.; Christoffersen, K.

    2001-01-01

    . Regardless of microcystin content, both Daphnia exhibited significantly reduced ingestion rates when fed with either strain of M. aeruginosa compared with the green alga Scenedesmus acutus. A disruption of the molting process in both Daphnia spp. was noted when these species were fed with MRC cells...

  19. ORF Alignment: NC_006840 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available NC_006840 gi|59711513 >1iwlA 4 181 21 198 9e-49 ... ref|YP_204289.1| outer-membrane lipoproteins... carrier protein [Vibrio fischeri ES114] ... gb|AAW85401.1| outer-membrane lipoproteins ca

  20. Luminescence, virulence and quorum sensing signal production by pathogenic Vibrio campbellii and Vibrio harveyi isolates.

    Science.gov (United States)

    Defoirdt, T; Verstraete, W; Bossier, P

    2008-05-01

    To study the relationship between luminescence, autoinducer production and virulence of pathogenic vibrios. Luminescence, quorum sensing signal production and virulence towards brine shrimp nauplii of 13 Vibrio campbellii and Vibrio harveyi strains were studied. Although only two of the tested strains were brightly luminescent, all of them were shown to produce the three different types of quorum sensing signals known to be produced by Vibrio harveyi. Cell-free culture fluids of all strains significantly induced bioluminescence in the cholerae autoinducer 1, autoinducer 2 and harveyi autoinducer 1 reporter strains JAF375, JMH597 and JMH612, respectively. There was no relation between luminescence and signal production and virulence towards brine shrimp. There is a large difference between different strains of Vibrio campbellii and Vibrio harveyi with respect to bioluminescence. However, this is not reflected in signal production and virulence towards gnotobiotic brine shrimp. Moreover, there seems to be no relation between quorum sensing signal production and virulence towards brine shrimp. The results presented here indicate that strains that are most brightly luminescent are not necessarily the most virulent ones and that the lower virulence of some of the strains is not due to a lack of autoinducer production.

  1. Genomic taxonomy of vibrios

    Directory of Open Access Journals (Sweden)

    Iida Tetsuya

    2009-10-01

    Full Text Available Abstract Background Vibrio taxonomy has been based on a polyphasic approach. In this study, we retrieve useful taxonomic information (i.e. data that can be used to distinguish different taxonomic levels, such as species and genera from 32 genome sequences of different vibrio species. We use a variety of tools to explore the taxonomic relationship between the sequenced genomes, including Multilocus Sequence Analysis (MLSA, supertrees, Average Amino Acid Identity (AAI, genomic signatures, and Genome BLAST atlases. Our aim is to analyse the usefulness of these tools for species identification in vibrios. Results We have generated four new genome sequences of three Vibrio species, i.e., V. alginolyticus 40B, V. harveyi-like 1DA3, and V. mimicus strains VM573 and VM603, and present a broad analyses of these genomes along with other sequenced Vibrio species. The genome atlas and pangenome plots provide a tantalizing image of the genomic differences that occur between closely related sister species, e.g. V. cholerae and V. mimicus. The vibrio pangenome contains around 26504 genes. The V. cholerae core genome and pangenome consist of 1520 and 6923 genes, respectively. Pangenomes might allow different strains of V. cholerae to occupy different niches. MLSA and supertree analyses resulted in a similar phylogenetic picture, with a clear distinction of four groups (Vibrio core group, V. cholerae-V. mimicus, Aliivibrio spp., and Photobacterium spp.. A Vibrio species is defined as a group of strains that share > 95% DNA identity in MLSA and supertree analysis, > 96% AAI, ≤ 10 genome signature dissimilarity, and > 61% proteome identity. Strains of the same species and species of the same genus will form monophyletic groups on the basis of MLSA and supertree. Conclusion The combination of different analytical and bioinformatics tools will enable the most accurate species identification through genomic computational analysis. This endeavour will culminate in

  2. AKTIVITAS ANTIBAKTERI EKSTRAK BUAH ADAS (Foeniculum vulgare, Mill PADA Vibrio harveyi DAN Vibrio alginolyticus Antibacterial Activity of Fennel (Foeniculum vulgare Mill Extract on Vibrio alginolyticus and Vibrio harveyi

    Directory of Open Access Journals (Sweden)

    Budianto Budianto

    2015-10-01

    Pada penelitian ini menggunakan ekstrak air dari buah adas untuk mengetahui aktivitas antibakteri terhadap Vibrio harveyi dan Vibrio alginolyticus dengan menggunakan metode uji Minimum Inhibitory Concentration (MIC dan difusi cakram kertas. Hasil yang diperoleh pada uji MIC, konsentrasi terkecil untuk menghambat pertumbuhan adalah 0,060 g/ml, untuk kedua spesies bakteri. Variasi perlakuan pada uji cakram kertas yaitu konsentrasi A (0,065 g/ml, B (0,070 g/ml, C (0,075 g/ml, D (0,080 g/ml, E (0,085 g/ml, F (0,090 g/ml dan kontrol (0,000 g/ml, hasil yang diperoleh adalah konsentrasi 0,090 g/ml memiliki diameter zona hambat tertinggi sebesar 11,17 ± 0,5 mm (V. harveyi dan 12,53 ± 1,14 mm (V. alginolyticus, sehingga dapat disimpulkan bahwa buah adas (F. vulgare Mill memiliki peranan ekologi yang sangat penting sebagai bahan pengobatan alternatif dalam pengendalian penyebaran penyakit Vibriosis yang disebabkan oleh V. harveyi dan V. alginolyticus. Kata kunci: Foeniculum vulgare Mill, Vibrio harveyi, Vibrio alginolyticus, uji MIC dan difusi cakram kertas

  3. Candidate innate immune system gene expression in the ecological model Daphnia.

    Science.gov (United States)

    Decaestecker, Ellen; Labbé, Pierrick; Ellegaard, Kirsten; Allen, Judith E; Little, Tom J

    2011-10-01

    The last ten years have witnessed increasing interest in host-pathogen interactions involving invertebrate hosts. The invertebrate innate immune system is now relatively well characterised, but in a limited range of genetic model organisms and under a limited number of conditions. Immune systems have been little studied under real-world scenarios of environmental variation and parasitism. Thus, we have investigated expression of candidate innate immune system genes in the water flea Daphnia, a model organism for ecological genetics, and whose capacity for clonal reproduction facilitates an exceptionally rigorous control of exposure dose or the study of responses at many time points. A unique characteristic of the particular Daphnia clones and pathogen strain combinations used presently is that they have been shown to be involved in specific host-pathogen coevolutionary interactions in the wild. We choose five genes, which are strong candidates to be involved in Daphnia-pathogen interactions, given that they have been shown to code for immune effectors in related organisms. Differential expression of these genes was quantified by qRT-PCR following exposure to the bacterial pathogen Pasteuria ramosa. Constitutive expression levels differed between host genotypes, and some genes appeared to show correlated expression. However, none of the genes appeared to show a major modification of expression level in response to Pasteuria exposure. By applying knowledge from related genetic model organisms (e.g. Drosophila) to models for the study of evolutionary ecology and coevolution (i.e. Daphnia), the candidate gene approach is temptingly efficient. However, our results show that detection of only weak patterns is likely if one chooses target genes for study based on previously identified genome sequences by comparison to homologues from other related organisms. Future work on the Daphnia-Pasteuria system will need to balance a candidate gene approach with more comprehensive

  4. Evaluation of the toxicity of two soils from Jales Mine (Portugal) using aquatic bioassays.

    Science.gov (United States)

    Loureiro, Susana; Ferreira, Abel L G; Soares, Amadeu M V M; Nogueira, António J A

    2005-10-01

    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 cladoceran Daphnia magna and the marine bacteria Vibrio fischeri. The habitat function of soils was evaluated with the reproduction bioassay with the collembolan Folsomia candida. The Microtox solid-phase test was performed with V. fischeri using soil as test medium, and soil elutriates were extracted to perform the Microtox basic test, and an immobilization and reproduction bioassay with D. magna. The marine bacteria showed high sensitivity to the soil with low heavy metal content (JNC soil) and to JNC soil elutriates, while the soil with highest heavy metal content (JC soil) or soil elutriates exposure did not cause any toxic effect. In the bioassays with D. magna, organisms showed sensitivity to JNC and also to JC soil elutriates. Both mobilization and reproduction features were inhibited. The bioassay with F. candida did not reflect any influence of the contaminants on their reproduction. Although JNC soil presented lower heavy metal contents, elutriates showed different patterns of contamination when compared to JC soil and elutriates, which indicates different retention and buffer capacities between soils. Results obtained in this study underlined the sensitivity and importance of soil elutriate bioassays with aquatic organisms in the evaluation strategy in soil ERA processes.

  5. Toxicological assessment of indium nitrate on aquatic organisms and investigation of the effects on the PLHC-1 fish cell line

    Energy Technology Data Exchange (ETDEWEB)

    Zurita, Jorge L. [National Institute of Toxicology and Forensic Sciences, Av. Dr Fedriani s/n, 41009, Seville (Spain); Jos, Angeles [Area of Toxicology, University of Seville, Prof. Garcia Gonzalez 2, 41012, Seville (Spain); Peso, Ana del; Salguero, Manuel [National Institute of Toxicology and Forensic Sciences, Av. Dr Fedriani s/n, 41009, Seville (Spain); Camean, Ana M. [Area of Toxicology, University of Seville, Prof. Garcia Gonzalez 2, 41012, Seville (Spain); Lopez-Artiguez, Miguel [National Institute of Toxicology and Forensic Sciences, Av. Dr Fedriani s/n, 41009, Seville (Spain); Repetto, Guillermo [National Institute of Toxicology and Forensic Sciences, Av. Dr Fedriani s/n, 41009, Seville (Spain); Area of Toxicology, University of Seville, Prof. Garcia Gonzalez 2, 41012, Seville (Spain)], E-mail: repetto@us.es

    2007-11-15

    Indium nitrate is mainly used as a semiconductor in batteries, for plating and other chemical and medical applications. There is a lack of available information about the adverse effects of indium compounds on aquatic organisms. Therefore, the toxic effects on systems from four trophic levels of the aquatic ecosystem were investigated. Firstly, the bacterium Vibrio fischeri, the alga Chlorella vulgaris and the cladoceran Daphnia magna were used in the toxicological evaluation of indium nitrate. The most sensitive model was V. fischeri, with a NOAEL of 0.02 and an EC{sub 50} of 0.04 mM at 15 min. Although indium nitrate should be classified as harmful to aquatic organisms, it is not expected to represent acute risk to the aquatic biota. Secondly, PLHC-1 fish cell line was employed to investigate the effects and mechanisms of toxicity. Although protein content, neutral red uptake, methylthiazol metabolization, lysosomal function and acetylcholinesterase activity were reduced in cells, stimulations were observed for metallothionein levels and succinate dehydrogenase and glucose-6-phosphate dehydrogenase activities. No changes were observed in ethoxyresorufin-O-deethylase activity. To clarify the main events in PLHC-1 cell death induced by indium nitrate, nine modulators were applied. They were related to oxidative stress ({alpha}-tocopherol succinate, mannitol and sodium benzoate), disruption of calcium homeostasis (BAPTA-AM and EGTA), thiol protection (1,4-dithiotreitol), iron chelation (deferoxiamine) or regulation of glutathione levels (2-oxothiazolidine-4-carboxylic acid and malic acid diethyl ester). The main morphological alterations were hydropic degeneration and loss of cells. At least, in partly, toxicity seems to be mediated by oxidative stress, and particularly by NADPH-dependent lipid peroxidation.

  6. Toxicological assessment of indium nitrate on aquatic organisms and investigation of the effects on the PLHC-1 fish cell line

    International Nuclear Information System (INIS)

    Zurita, Jorge L.; Jos, Angeles; Peso, Ana del; Salguero, Manuel; Camean, Ana M.; Lopez-Artiguez, Miguel; Repetto, Guillermo

    2007-01-01

    Indium nitrate is mainly used as a semiconductor in batteries, for plating and other chemical and medical applications. There is a lack of available information about the adverse effects of indium compounds on aquatic organisms. Therefore, the toxic effects on systems from four trophic levels of the aquatic ecosystem were investigated. Firstly, the bacterium Vibrio fischeri, the alga Chlorella vulgaris and the cladoceran Daphnia magna were used in the toxicological evaluation of indium nitrate. The most sensitive model was V. fischeri, with a NOAEL of 0.02 and an EC 50 of 0.04 mM at 15 min. Although indium nitrate should be classified as harmful to aquatic organisms, it is not expected to represent acute risk to the aquatic biota. Secondly, PLHC-1 fish cell line was employed to investigate the effects and mechanisms of toxicity. Although protein content, neutral red uptake, methylthiazol metabolization, lysosomal function and acetylcholinesterase activity were reduced in cells, stimulations were observed for metallothionein levels and succinate dehydrogenase and glucose-6-phosphate dehydrogenase activities. No changes were observed in ethoxyresorufin-O-deethylase activity. To clarify the main events in PLHC-1 cell death induced by indium nitrate, nine modulators were applied. They were related to oxidative stress (α-tocopherol succinate, mannitol and sodium benzoate), disruption of calcium homeostasis (BAPTA-AM and EGTA), thiol protection (1,4-dithiotreitol), iron chelation (deferoxiamine) or regulation of glutathione levels (2-oxothiazolidine-4-carboxylic acid and malic acid diethyl ester). The main morphological alterations were hydropic degeneration and loss of cells. At least, in partly, toxicity seems to be mediated by oxidative stress, and particularly by NADPH-dependent lipid peroxidation

  7. Genomic taxonomy of vibrios

    DEFF Research Database (Denmark)

    Thompson, Cristiane C.; Vicente, Ana Carolina P.; Souza, Rangel C.

    2009-01-01

    BACKGROUND: Vibrio taxonomy has been based on a polyphasic approach. In this study, we retrieve useful taxonomic information (i.e. data that can be used to distinguish different taxonomic levels, such as species and genera) from 32 genome sequences of different vibrio species. We use a variety of...

  8. EFFECTS OF ULTRAVIOLET-B LIGHT AND POLYAROMATIC HYDROCARBON EXPOSURE ON SEA URCHIN DEVELOPMENT AND BACTERIAL BIOLUMINESCENCE

    Science.gov (United States)

    Polycyclic aromatic hydrocarbons (PAHs) are relatively common contaminants of the Gulf of Mexico and may be activated to more toxic metabolites by ultraviolet-B (UV-B) light. A marine bacterial bioassay system (Vibrio fischeri) which focused on the reduction of luciferase-mediate...

  9. Biogeography of the ‘water flea’ Daphnia O. F. Müller (Crustacea: Branchiopoda: Anomopoda on the Indian subcontinent

    Directory of Open Access Journals (Sweden)

    Sameer M. Padhye

    2016-06-01

    Full Text Available Studies on Daphnia distribution in Indian subcontinent have been few and regionally restricted despite Daphnia being by far the most studied cladoceran. We here present a first biogeographical assessment of the genus on the Indian subcontinent (Afghanistan, Pakistan, India, Nepal, Bhutan, Bangladesh and Sri Lanka. We collected all pertinent literature and considered nineteen bioclimatic variables along with latitude, longitude, and altitude for statistical analysis of factors governing distribution in space. Significant variables (determined by Kruskal Wallis test were tested by nonparametric multivariate analysis of variance (PERMANOVA to clarify whether Daphnia species had specific environmental requirements. Canonical correspondence analysis was used to understand how environmental variables affected distribution.  Eight Daphnia (Ctenodaphnia and 4 Daphnia s.str. occurred at 100 different localities. The variables temperature, altitude and latitude differed among species and so did their bio-climatic requirements. Daphnia distribution responded positively to altitude and negatively to a decrease in latitude and temperature.

  10. Luminescence, virulence and quorum sensing signal production by pathogenic Vibrio campbellii and Vibrio harveyi isolates

    OpenAIRE

    Defoirdt, T.; Verstraete, W.; Bossier, P.

    2008-01-01

    Aims: To study the relationship between luminescence, autoinducer production and virulence of pathogenic vibrios.Methods and Results: Luminescence, quorum sensing signal production and virulence towards brine shrimp nauplii of 13 Vibrio campbellii and Vibrio harveyi strains were studied. Although only two of the tested strains were brightly luminescent, all of them were shown to produce the three different types of quorum sensing signals known to be produced by Vibrio harveyi. Cell-free cultu...

  11. Passive Immune-Protection of Litopenaeus vannamei against Vibrio harveyi and Vibrio parahaemolyticus Infections with Anti-Vibrio Egg Yolk (IgY-Encapsulated Feed

    Directory of Open Access Journals (Sweden)

    Xiaojian Gao

    2016-05-01

    Full Text Available Vibrio spp. are major causes of mortality in white shrimp (Litopenaeus vannamei which is lacking adaptive immunity. Passive immunization with a specific egg yolk antibody (IgY is a potential method for the protection of shrimp against vibriosis. In this study, immune effects of the specific egg yolk powders (IgY against both V. harveyi and V. parahaemolyticus on white shrimp were evaluated. The egg yolk powders against V. harveyi and V. parahaemolyticus for passive immunization of white shrimp were prepared, while a tube agglutination assay and an indirect enzyme-linked immunosorbent assay (ELISA were used for detection of IgY titer. Anti-Vibrio egg yolk was encapsulated by β-cyclodextrin, which could keep the activity of the antibody in the gastrointestinal tract of shrimp. The results showed that the anti-Vibrio egg powders had an inhibiting effect on V. harveyi and V. parahaemolyticus in vitro. Lower mortality of infected zoeae, mysis, and postlarva was observed in groups fed with anti-Vibrio egg powders, compared with those fed with normal egg powders. The bacterial load in postlarva fed with specific egg powders in seeding ponds was significantly lower than those fed with normal egg powders in seeding ponds. These results show that passive immunization by oral administration with specific egg yolk powders (IgY may provide a valuable protection of vibrio infections in white shrimp.

  12. Chytrid parasitism facilitates trophic transfer between bloom-forming cyanobacteria and zooplankton (Daphnia).

    Science.gov (United States)

    Agha, Ramsy; Saebelfeld, Manja; Manthey, Christin; Rohrlack, Thomas; Wolinska, Justyna

    2016-10-13

    Parasites are rarely included in food web studies, although they can strongly alter trophic interactions. In aquatic ecosystems, poorly grazed cyanobacteria often dominate phytoplankton communities, leading to the decoupling of primary and secondary production. Here, we addressed the interface between predator-prey and host-parasite interactions by conducting a life-table experiment, in which four Daphnia galeata genotypes were maintained on quantitatively comparable diets consisting of healthy cyanobacteria or cyanobacteria infected by a fungal (chytrid) parasite. In four out of five fitness parameters, at least one Daphnia genotype performed better on parasitised cyanobacteria than in the absence of infection. Further treatments consisting of purified chytrid zoospores and heterotrophic bacteria suspensions established the causes of improved fitness. First, Daphnia feed on chytrid zoospores which trophically upgrade cyanobacterial carbon. Second, an increase in heterotrophic bacterial biomass, promoted by cyanobacterial decay, provides an additional food source for Daphnia. In addition, chytrid infection induces fragmentation of cyanobacterial filaments, which could render cyanobacteria more edible. Our results demonstrate that chytrid parasitism can sustain zooplankton under cyanobacterial bloom conditions, and exemplify the potential of parasites to alter interactions between trophic levels.

  13. A rapid bioassay for detecting saxitoxins using a Daphnia acute toxicity test

    Energy Technology Data Exchange (ETDEWEB)

    Ferrao-Filho, Aloysio da S., E-mail: aloysio@ioc.fiocruz.b [Laboratorio de Avaliacao e Promocao da Saude Ambiental, Departamento de Biologia, Instituto Oswaldo Cruz, FIOCRUZ, Av. Brasil 4365, Manguinhos, Rio de Janeiro, RJ 21045-900 (Brazil); Soares, Maria Carolina S., E-mail: mcarolsoares@gmail.co [Departamento de Engenharia Sanitaria e Ambiental Faculdade de Engenharia, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-900 (Brazil); Freitas de Magalhaes, Valeria, E-mail: valeria@biof.ufrj.b [Laboratorio de Ecofisiologia e Toxicologia de Cianobacterias, Instituto de Biofisica Carlos Chagas Filho, CCS, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Rio de Janeiro, RJ 21949-900 (Brazil); Azevedo, Sandra M.F.O., E-mail: sazevedo@biof.ufrj.b [Laboratorio de Ecofisiologia e Toxicologia de Cianobacterias, Instituto de Biofisica Carlos Chagas Filho, CCS, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Rio de Janeiro, RJ 21949-900 (Brazil)

    2010-06-15

    Bioassays using Daphnia pulex and Moina micrura were designed to detect cyanobacterial neurotoxins in raw water samples. Phytoplankton and cyanotoxins from seston were analyzed during 15 months in a eutrophic reservoir. Effective time to immobilize 50% of the exposed individuals (ET{sub 50}) was adopted as the endpoint. Paralysis of swimming movements was observed between approx0.5-3 h of exposure to lake water containing toxic cyanobacteria, followed by an almost complete recovery of the swimming activity within 24 h after being placed in control water. The same effects were observed in bioassays with a saxitoxin-producer strain of Cylindrospermopsis raciborskii isolated from the reservoir. Regression analysis showed significant relationships between ET{sub 50}vs. cell density, biomass and saxitoxins content, suggesting that the paralysis of Daphnia in lake water samples was caused by saxitoxins found in C. raciborskii. Daphnia bioassay was found to be a sensitive method for detecting fast-acting neurotoxins in natural samples, with important advantages over mouse bioassays. - A new Daphnia bioassay, as an alternative to the mouse bioassay, is able to detect effects of fast-acting, potent neurotoxins in raw water.

  14. A rapid bioassay for detecting saxitoxins using a Daphnia acute toxicity test

    International Nuclear Information System (INIS)

    Ferrao-Filho, Aloysio da S.; Soares, Maria Carolina S.; Freitas de Magalhaes, Valeria; Azevedo, Sandra M.F.O.

    2010-01-01

    Bioassays using Daphnia pulex and Moina micrura were designed to detect cyanobacterial neurotoxins in raw water samples. Phytoplankton and cyanotoxins from seston were analyzed during 15 months in a eutrophic reservoir. Effective time to immobilize 50% of the exposed individuals (ET 50 ) was adopted as the endpoint. Paralysis of swimming movements was observed between ∼0.5-3 h of exposure to lake water containing toxic cyanobacteria, followed by an almost complete recovery of the swimming activity within 24 h after being placed in control water. The same effects were observed in bioassays with a saxitoxin-producer strain of Cylindrospermopsis raciborskii isolated from the reservoir. Regression analysis showed significant relationships between ET 50 vs. cell density, biomass and saxitoxins content, suggesting that the paralysis of Daphnia in lake water samples was caused by saxitoxins found in C. raciborskii. Daphnia bioassay was found to be a sensitive method for detecting fast-acting neurotoxins in natural samples, with important advantages over mouse bioassays. - A new Daphnia bioassay, as an alternative to the mouse bioassay, is able to detect effects of fast-acting, potent neurotoxins in raw water.

  15. Microbial Ecophysiology of Vibrio ruber

    Directory of Open Access Journals (Sweden)

    Tjaša Danevčič

    2014-01-01

    Full Text Available Bacteria use different adaptation strategies to survive environmental perturbations. In this minireview, adaptation strategies of new red-pigmented Vibrio ruber isolated from coastal environments to different environmental stresses (i.e. salinity, viscosity, UV light, mitomycin C, nutrient availability and temperature are reviewed. To cope with environmental stresses Vibrio ruber uses several different adaptive strategies. For example, lipid composition as well as phase behaviour are strongly dependent on salt concentration. Vibrio ruber membrane has no hydroxy fatty acids, but exceptionally high lysolipid content compared to other related Vibrio species. Inorganic nutrient uptake by bacteria is selective, depends on environmental conditions and varies several fold with environmental perturbations. Protein composition, carbon flow through the central metabolic pathways, energy generation as well as secondary metabolite production adapt readily to stress conditions. The activity of glucose-6-phosphate dehydrogenase proved to be a good indicator of Vibrio ruber stress. Cells are able to modulate their local viscosity in response to variations of environmental viscosity. The bacterium harbours several viral genetic elements in its genome, which could be induced by mitomycin C. Environmental conditions during growth of bacteria have a significant effect on lysate carbon turnover. Secondary metabolite prodigiosin confers protection against UV in the environment, which adds to the known repertoire of prodigiosin ecophysiological functions. In conclusion, Vibrio ruber in its short acquaintance with the scientific community (less than ten years has proven to be an immensely valuable model system for ecophysiological studies of bacteria.

  16. Maternal nutritional state determines the sensitivity of Daphnia magna offspring to Fenvalerate pulse exposure.

    NARCIS (Netherlands)

    Pieters, B.J.; Liess, M.

    2006-01-01

    Abstract Daphnia populations in the field suffer periodic natural stress conditions such as low food levels. It is known that at low nutritional supply, Daphnia produces fewer but larger offspring, which are acutely less sensitive to chemical stress. We hypothesized that the change in the

  17. Crayfish: a newly recognized vehicle for vibrio infections.

    Science.gov (United States)

    Bean, N H; Maloney, E K; Potter, M E; Korazemo, P; Ray, B; Taylor, J P; Seigler, S; Snowden, J

    1998-10-01

    We conducted a 1-year case-control study of sporadic vibrio infections to identify risk factors related to consumption of seafood products in two coastal areas of Louisiana and Texas. Twenty-six persons with sporadic vibrio infections and 77 matched controls were enrolled. Multivariate analysis revealed that crayfish (P Vibrio parahemolyticus infection (OR 9.24, P vibrio infection.

  18. Vibrio Parahaemolyticus: The Threat of Another Vibrio Acquiring Pandemic Potential

    Digital Repository Service at National Institute of Oceanography (India)

    Ramamurthy, T.; Nair, G.B.

    investigations of Vibrio parahaemolyticus in oysters following outbreaks in Washington, Texas, and New York. (1997 and 1998). Appl. Envrion. Microbiol. 66, 4649- 4654. DePaola, A., Ulaszek, J., Kaysner, C. A., Tenge, B. J., Nordstrom, J. L., Wells, J., Puhr, N...-710. Andrews, L. S., DeBlanc, S., Veal, C. D., Park, D. L., 2003. Response of Vibrio parahaemolyticus O3:K6 to a hot water/ cold shock pasteurization process. Food Addit. Contam. 20, 331-334. Bag, P. K., Nandi, S., Bhadra, R. K., Ramamurthy, T., Bhattacharya, S...

  19. Responses in sediment bioassays used in the Netherlands: can observed toxicity be explained by routinely monitored priority pollutants?

    NARCIS (Netherlands)

    Lahr, J.; Maas-Diepeveen, J.L.; Stuijfzand, S.C.; Leonards, P.E.G.; Drueke, J.M.; Luecker, S.; Espeldoorn, A.

    2003-01-01

    In order to identify the cause of toxicity in sediments and suspended matter, a large number of samples with different degrees of contamination was taken at various locations in The Netherlands. Standard acute bioassays were carried out with the bacterium Vibrio fischeri, the rotifer Brachionus

  20. Prevalence study of Vibrio species and frequency of the virulence genes of Vibrio parahaemolyticus isolated from fresh and salted shrimps in Genaveh seaport

    Directory of Open Access Journals (Sweden)

    S Hosseini

    2014-08-01

    Full Text Available Vibrio species are important seafood-borne pathogens that are responsible for 50-70% of gasteroenteritis. The present study was carried out in order to determine the prevalence of Vibrio species and the distribution of tdh, tlh and trh virulence genes in Vibrio parahaemolyticus isolated from fresh and salted shrimp samples. Totally, 60 fresh and salted shrimp samples were collected from the Genaveh seaport. Microbial culture was used to isolate Vibrio species. In addition, the presences of Vibrio parahaemolyticus, Vibrio cholera, Vibrio vulnificus and Vibrio harveyi and the virulence genes of V. parahaemolyticus were studied using the PCR method. Results showed that 20% of fresh and 23.33% of salted shrimp samples were positive for Vibrio species. In studied samples, V. vulnificus had the highest prevalence rate (8.33%, while V. cholera had the lowest prevalence rate (1.66%. From a total of 4 detected V. parahaemolyticus, all of them had tlh gene (100%. The distribution of tdh and trh genes in isolated V. parahaemolyticus strains were 50% and 25%, respectively. High prevalence of Vibrio species and especially virulent V. parahaemolyticus in samples confirmed the lack of hygienic condition in the production and distribution centers of shrimp.

  1. Bovine Lactoferrin and Lactoferrin-Derived Peptides Inhibit the Growth of Vibrio cholerae and Other Vibrio species

    Directory of Open Access Journals (Sweden)

    Erika Acosta-Smith

    2018-01-01

    Full Text Available Vibrio is a genus of Gram-negative bacteria, some of which can cause serious infectious diseases. Vibrio infections are associated with the consumption of contaminated food and classified in Vibrio cholera infections and non-cholera Vibrio infections. In the present study, we investigate whether bovine lactoferrin (bLF and several synthetic peptides corresponding to bLF sequences, are able to inhibit the growth or have bactericidal effect against V. cholerae and other Vibrio species. The antibacterial activity of LF and LF-peptides was assessed by kinetics of growth or determination of colony forming unit in bacteria treated with the peptides and antibiotics. To get insight in the mode of action, the interaction between bLF and bLF-peptides (coupled to FITC and V. cholera was evaluated. The damage of effector-induced bacterial membrane permeability was measured by inclusion of the fluorescent dye propidium iodide using flow cytometry, whereas the bacterial ultrastructural damage in bacteria treated was observed by transmission electron microscopy. The results showed that bLF and LFchimera inhibited the growth of the V. cholerae strains; LFchimera permeabilized the bacteria which membranes were seriously damaged. Assays with a multidrug-resistant strain of Vibrio species indicated that combination of sub-lethal doses of LFchimera with ampicillin or tetracycline strongly reduced the concentration of the antibiotics to reach 95% growth inhibition. Furthermore, LFchimera were effective to inhibit the V. cholerae counts and damage due to this bacterium in a model mice. These data suggest that LFchimera and bLF are potential candidates to combat the V. cholerae and other multidrug resistant Vibrio species.

  2. Bovine Lactoferrin and Lactoferrin-Derived Peptides Inhibit the Growth of Vibrio cholerae and Other Vibrio species

    Science.gov (United States)

    Acosta-Smith, Erika; Viveros-Jiménez, Karina; Canizalez-Román, Adrian; Reyes-Lopez, Magda; Bolscher, Jan G. M.; Nazmi, Kamran; Flores-Villaseñor, Hector; Alapizco-Castro, Gerardo; de la Garza, Mireya; Martínez-Garcia, Jesús J.; Velazquez-Roman, Jorge; Leon-Sicairos, Nidia

    2018-01-01

    Vibrio is a genus of Gram-negative bacteria, some of which can cause serious infectious diseases. Vibrio infections are associated with the consumption of contaminated food and classified in Vibrio cholera infections and non-cholera Vibrio infections. In the present study, we investigate whether bovine lactoferrin (bLF) and several synthetic peptides corresponding to bLF sequences, are able to inhibit the growth or have bactericidal effect against V. cholerae and other Vibrio species. The antibacterial activity of LF and LF-peptides was assessed by kinetics of growth or determination of colony forming unit in bacteria treated with the peptides and antibiotics. To get insight in the mode of action, the interaction between bLF and bLF-peptides (coupled to FITC) and V. cholera was evaluated. The damage of effector-induced bacterial membrane permeability was measured by inclusion of the fluorescent dye propidium iodide using flow cytometry, whereas the bacterial ultrastructural damage in bacteria treated was observed by transmission electron microscopy. The results showed that bLF and LFchimera inhibited the growth of the V. cholerae strains; LFchimera permeabilized the bacteria which membranes were seriously damaged. Assays with a multidrug-resistant strain of Vibrio species indicated that combination of sub-lethal doses of LFchimera with ampicillin or tetracycline strongly reduced the concentration of the antibiotics to reach 95% growth inhibition. Furthermore, LFchimera were effective to inhibit the V. cholerae counts and damage due to this bacterium in a model mice. These data suggest that LFchimera and bLF are potential candidates to combat the V. cholerae and other multidrug resistant Vibrio species. PMID:29375503

  3. Mating in the Closest Living Relatives of Animals Is Induced by a Bacterial Chondroitinase.

    Science.gov (United States)

    Woznica, Arielle; Gerdt, Joseph P; Hulett, Ryan E; Clardy, Jon; King, Nicole

    2017-09-07

    We serendipitously discovered that the marine bacterium Vibrio fischeri induces sexual reproduction in one of the closest living relatives of animals, the choanoflagellate Salpingoeca rosetta. Although bacteria influence everything from nutrition and metabolism to cell biology and development in eukaryotes, bacterial regulation of eukaryotic mating was unexpected. Here, we show that a single V. fischeri protein, the previously uncharacterized EroS, fully recapitulates the aphrodisiac-like activity of live V. fischeri. EroS is a chondroitin lyase; although its substrate, chondroitin sulfate, was previously thought to be an animal synapomorphy, we demonstrate that S. rosetta produces chondroitin sulfate and thus extend the ancestry of this important glycosaminoglycan to the premetazoan era. Finally, we show that V. fischeri, purified EroS, and other bacterial chondroitin lyases induce S. rosetta mating at environmentally relevant concentrations, suggesting that bacteria likely regulate choanoflagellate mating in nature. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Molecular cloning and expression of the luciferase coding genes of ...

    African Journals Online (AJOL)

    User

    2011-05-16

    May 16, 2011 ... Vibrio fischeri is a symbiotic marine bacterium and a nonpathogenic member of the .... colony was inoculated into a medium (1.2% Bacto tryptone, 2.4% yeast extract, 0.04% glycerol, 1% M9 salts (6.4% Na2HPO4-7H20,.

  5. Use of a Whole-Cell Biosensor and Flow Cytometry to Detect AHL Production by an Indigenous Soil Community During Decomposition

    DEFF Research Database (Denmark)

    Burmølle, Mette; Hansen, Lars Hestbjerg; Sørensen, Søren Johannes

    2005-01-01

    originating from Vibrio fischeri. This resulted in a whole-cell biosensor, responding to the presence of AHL compounds. The biosensor was introduced to compost soil microcosms amended with nettle leaves. After 3 days of incubation, cells were extracted and analyzed by flow cytometry. All microcosms contained...

  6. Acute toxicity of birch tar oil on aquatic organisms

    Directory of Open Access Journals (Sweden)

    M. HAGNER

    2008-12-01

    Full Text Available Birch tar oil (BTO is a by-product of processing birch wood in a pyrolysis system. Accumulating evidence suggests the suitability of BTO as a biocide or repellent in terrestrial environments for the control of weeds, insects, molluscs and rodents. Once applied as biocide, BTO may end up, either through run-off or leaching, in aquatic systems and may have adverse effects on non-target organisms. As very little is known about the toxicity of BTO to aquatic organisms, the present study investigated acute toxicity (LC50/EC50 of BTO for eight aquatic organisms. Bioassays with the Asellus aquaticus (crustacean, Lumbriculus variegatus (oligochaeta worm, Daphnia magna (crustacean, Lymnea sp. (mollusc, Lemna minor (vascular plant, Danio rerio (fish, Scenedesmus gracilis (algae, and Vibrio fischeri (bacterium were performed according to ISO, OECD or USEPA-guidelines. The results indicated that BTO was practically nontoxic to most aquatic organisms as the median effective BTO concentrations against most organisms were >150 mg L-1. In conclusion, our toxicity tests showed that aquatic organisms are to some extent, invariably sensitive to birch tar oil, but suggest that BTO does not pose a severe hazard to aquatic biota. We deduce that, unless BTOs are not applied in the immediate vicinity of water bodies, no special precaution is required.;

  7. A comparative toxicity assessment of materials used in aquatic construction.

    Science.gov (United States)

    Lalonde, Benoit A; Ernst, William; Julien, Gary; Jackman, Paula; Doe, Ken; Schaefer, Rebecca

    2011-10-01

    Comparative toxicity testing was performed on selected materials that may be used in aquatic construction projects. The tests were conducted on the following materials: (1) untreated wood species (hemlock [Tsuga ssp], Western red cedar (Thuja plicata), red oak [Quercus rubra], Douglas fir [Pseudotsuga menziesii], red pine [Pinus resinosa], and tamarack [Larix ssp]); (2) plastic wood; (3) Ecothermo wood hemlock stakes treated with preservatives (e.g., chromated copper arsenate [CCA], creosote, alkaline copper quaternary [ACQ], zinc naphthenate, copper naphthenate, and Lifetime Wood Treatment); (4) epoxy-coated steel; (5) hot-rolled steel; (6) zinc-coated steel; and (7) concrete. Those materials were used in acute lethality tests with rainbow trout, Daphnia magna, Vibrio fischeri and threespine stickleback. The results indicated the following general ranking of the materials (from the lowest to highest LC(50) values); ACQ > creosote > zinc naphthenate > copper naphthenate > CCA (treated at 22.4 kg/m(3)) > concrete > red pine > western red cedar > red oak > zinc-coated steel > epoxy-coated steel > CCA (6.4 kg/m(3)). Furthermore, the toxicity results indicated that plastic wood, certain untreated wood species (hemlock, tamarack, Douglas fir, and red oak), hot-rolled steel, Ecothermo wood, and wood treated with Lifetime Wood Treatment were generally nontoxic to the test species. © Springer Science+Business Media, LLC 2011

  8. POTENSI BEBERAPA ISOLAT PROBIOTIK SEBAGAI ANTIBAKTERI TERHADAP PERTUMBUHAN Vibrio spp.

    OpenAIRE

    HASBIAH

    2015-01-01

    The research about potential of some probiotic isolates as an antibacterial on the growth of Vibrio spp had been done. This research aimed to know the antibacterial potency from some isolates probiotic on the growth of Vibrio spp. This research to tested the inhibition on the three species of Vibrio that are Vibrio harveyi, Vibrio prahaemolyticus, and Vibrio cholerae using agar diffusion method. Probiotic isolates come from lactic acid bacteria group that provide beneficial effects on health ...

  9. Resistance to Antimicrobial Peptides in Vibrios

    Directory of Open Access Journals (Sweden)

    Delphine Destoumieux-Garzón

    2014-10-01

    Full Text Available Vibrios are associated with a broad diversity of hosts that produce antimicrobial peptides (AMPs as part of their defense against microbial infections. In particular, vibrios colonize epithelia, which function as protective barriers and express AMPs as a first line of chemical defense against pathogens. Recent studies have shown they can also colonize phagocytes, key components of the animal immune system. Phagocytes infiltrate infected tissues and use AMPs to kill the phagocytosed microorganisms intracellularly, or deliver their antimicrobial content extracellularly to circumvent tissue infection. We review here the mechanisms by which vibrios have evolved the capacity to evade or resist the potent antimicrobial defenses of the immune cells or tissues they colonize. Among their strategies to resist killing by AMPs, primarily vibrios use membrane remodeling mechanisms. In particular, some highly resistant strains substitute hexaacylated Lipid A with a diglycine residue to reduce their negative surface charge, thereby lowering their electrostatic interactions with cationic AMPs. As a response to envelope stress, which can be induced by membrane-active agents including AMPs, vibrios also release outer membrane vesicles to create a protective membranous shield that traps extracellular AMPs and prevents interaction of the peptides with their own membranes. Finally, once AMPs have breached the bacterial membrane barriers, vibrios use RND efflux pumps, similar to those of other species, to transport AMPs out of their cytoplasmic space.

  10. Interactions between predator kairomone and food level complicate the ecological interpretation of Daphnia laboratory results

    NARCIS (Netherlands)

    Weber, A.

    2001-01-01

    The effect of food concentration on the phenotypic response of life history traits to two predator kairomones war investigated in Daphnia. For the experiment, one clone of Daphnia galeata war used as the prey organism and solutions containing infochemicals (kairomones) of Chaoborus (phantom midge)

  11. Male meiosis in Crustacea: synapsis, recombination, epigenetics and fertility in Daphnia magna.

    Science.gov (United States)

    Gómez, Rocío; Van Damme, Kay; Gosálvez, Jaime; Morán, Eugenio Sánchez; Colbourne, John K

    2016-09-01

    We present the first detailed cytological study of male meiosis in Daphnia (Crustacea: Branchiopoda: Cladocera)-an aquatic microcrustacean with a cyclical parthenogenetic life cycle. Using immunostaining of the testes in Daphnia magna for baseline knowledge, we characterized the different stages of meiotic division and spermiogenesis in relation to the distribution of proteins involved in synapsis, early recombination events and sister chromatid cohesion. We also studied post-translational histone modifications in male spermatocytes, in relation to the dynamic chromatin progression of meiosis. Finally, we applied a DNA fragmentation test to measure sperm quality of D. magna, with respect to levels of inbreeding. As a proxy for fertility, this technique may be used to assess the reproductive health of a sentinel species of aquatic ecosystems. Daphnia proves to be a model species for comparative studies of meiosis that is poised to improve our understanding of the cytological basis of sexual and asexual reproduction.

  12. NAPL migration and ecotoxicity of conventional and renewable fuels in accidental spill scenarios.

    Science.gov (United States)

    Malk, Vuokko; Barreto Tejera, Eduardo; Simpanen, Suvi; Dahl, Mari; Mäkelä, Riikka; Häkkinen, Jani; Kiiski, Anna; Penttinen, Olli-Pekka

    2014-01-01

    Fuels derived from non-petroleum renewable resources have raised interest due to their potential in replacing petroleum-based fuels, but information on their fate and effects in the terrestrial and aquatic environments in accidental spill scenario is limited. In this study, migration of four fuels (conventional diesel, conventional gasoline, renewable diesel NExBTL, and ethanol-blended gasoline RE85 containing maximum 85% ethanol) as non-aqueous phase liquids (NAPL) in soil was demonstrated in a laboratory-scale experiment. Ecotoxicity data was produced for the same fuels. There was no significant difference in migration of conventional and renewable diesel, but gasoline migrated 1.5 times deeper and 7-9 times faster in sand than diesel. RE85 spread horizontally wider but not as deep (p gasoline. Conventional gasoline was the most toxic (lethal concentration [LC50] 20 mg/kg total hydrocarbon content [THC]) among the studied fuels in soil toxicity test with earthworm Eisenia fetida followed by ethanol-blended gasoline (LC50 1,643 mg/kg THC) and conventional diesel (LC50 2,432 mg/kg THC), although gasoline evaporated fast from soil. For comparison, the toxicity of the water-accommodated fractions (WAF) of the fuels was tested with water flea Daphnia magna and Vibrio fischeri, also demonstrating groundwater toxicity. The WAF of conventional gasoline and RE85 showed almost similar toxicity to both the aquatic test species. EC50 values of 1:10 (by volume) WAF were 9.9 %WAF (gasoline) and 9.3 %WAF (RE85) to D. magna and 9.3 %WAF (gasoline) and 12.3 %WAF (RE85) to V. fischeri. Low solubility decreased toxicity potential of conventional diesel in aquatic environment, but direct physical effects of oil phase pose a threat to organisms in nature. Renewable diesel NExBTL did not show clear toxicity to any test species.

  13. Long-term effects to ionizing radiation in crustacean Daphnia magna

    International Nuclear Information System (INIS)

    Sarapul'tseva, E.I.

    2016-01-01

    The results of this study have provided strong evidence for the trans generational effects of parental exposure to ionizing radiation in crustacean Daphnia magna. To establish whether parental irradiation can affect the survival, life span and fertility of directly exposed organisms and their non-exposed offspring, D. magna were given 10, 100, 1000 and 10,000 mGy of acute γ-rays. MTT-assay was first applied for the investigation in vivo of the mechanisms of trans generational low doses effects of radiation and development of stress in Daphnia. Our dates strongly support MTT assay results as a good bio marker of survival and fertility effects at D. magna. (authors)

  14. Saturation mutagenesis of a CepR binding site as a means to identify new quorum-regulated promoters in Burkholderia cenocepacia

    Science.gov (United States)

    Burkholderia cenocepacia, an opportunistic pathogen of humans, encodes the CepI and CepR proteins, which resemble the LuxI and LuxR quorum sensing proteins of Vibrio fischeri. CepI directs the synthesis of octanoylhomoserine lactone (OHL), while CepR is an OHL dependent transcription factor. In pr...

  15. Impact of polystyrene microplastics on Daphnia magna mortality and reproduction in relation to food availability

    Science.gov (United States)

    Aljaibachi, Rana

    2018-01-01

    Microplastics (MPs) in the environment continue to be a growing area of concern in terms of acute and chronic impacts on aquatic life. Whilst increasing numbers of studies are providing important insights into microparticle behaviour and impacts in the marine environment, a paucity of information exists regarding the freshwater environment. This study focusses on the uptake, retention and the impact of 2 µm polystyrene MPs in the freshwater cladoceran Daphnia magna in relation to food intake (algae Chlorella vulgaris), with MP size chosen to approximately match the cell size of the algae. Daphnia were exposed to varied concentrations of MPs and algae. When exposed to a single concentration of MPs Daphnia almost immediately ate them in large quantities. However, the presence of algae, even at low concentrations, had a significant negative impact on MP uptake that was not in proportion to relative availability. As MP concentrations increased, intake did not if algae were present, even at higher concentrations of MPs. This suggests that Daphnia are selectively avoiding eating plastics. Adult Daphnia exposed to MPs for 21 days showed mortality after seven days of exposure in all treatments compared to the control. However significant differences were all related to algal concentration rather than to MP concentration. This suggests that where ample food is present, MPs have little effect on adults. There was also no impact on their reproduction. The neonate toxicity test confirmed previous results that mortality and reproduction was linked to availability of food rather than MP concentrations. This would make sense in light of our suggestion that Daphnia are selectively avoiding eating microplastics. PMID:29686944

  16. Impact of polystyrene microplastics on Daphnia magna mortality and reproduction in relation to food availability

    Directory of Open Access Journals (Sweden)

    Rana Aljaibachi

    2018-04-01

    Full Text Available Microplastics (MPs in the environment continue to be a growing area of concern in terms of acute and chronic impacts on aquatic life. Whilst increasing numbers of studies are providing important insights into microparticle behaviour and impacts in the marine environment, a paucity of information exists regarding the freshwater environment. This study focusses on the uptake, retention and the impact of 2 µm polystyrene MPs in the freshwater cladoceran Daphnia magna in relation to food intake (algae Chlorella vulgaris, with MP size chosen to approximately match the cell size of the algae. Daphnia were exposed to varied concentrations of MPs and algae. When exposed to a single concentration of MPs Daphnia almost immediately ate them in large quantities. However, the presence of algae, even at low concentrations, had a significant negative impact on MP uptake that was not in proportion to relative availability. As MP concentrations increased, intake did not if algae were present, even at higher concentrations of MPs. This suggests that Daphnia are selectively avoiding eating plastics. Adult Daphnia exposed to MPs for 21 days showed mortality after seven days of exposure in all treatments compared to the control. However significant differences were all related to algal concentration rather than to MP concentration. This suggests that where ample food is present, MPs have little effect on adults. There was also no impact on their reproduction. The neonate toxicity test confirmed previous results that mortality and reproduction was linked to availability of food rather than MP concentrations. This would make sense in light of our suggestion that Daphnia are selectively avoiding eating microplastics.

  17. Highly diverse recombining populations of Vibrio cholerae and Vibrio parahaemolyticus in French Mediterranean coastal lagoons

    Directory of Open Access Journals (Sweden)

    Kevin eEsteves

    2015-07-01

    Full Text Available Vibrio parahaemolyticus and Vibrio cholerae are ubiquitous to estuarine and marine environments. These two species can induce infections in humans. Therefore understanding the structure and dynamics of non-pandemic environmental populations in temperate regions, such as Mediterranean coastal systems, is important if we are to evaluate the risks of infection to humans.Environmental isolates of V. cholerae (n=109 and V. parahaemolyticus (n=89 sampled at different dates, stations and water salinities were investigated for virulence genes and by a multilocus sequence-based analysis (MLSA. V. cholerae isolates were all ctxA negative and only one isolate of V. parahaemolyticus displayed trh2 gene. Most Sequence Types (ST corresponded to unique ST isolated at one date or one station. Frequent recombination events were detected among different pathogenic species, V. parahaemolyticus, V. cholerae, Vibrio mimicus and Vibrio metoecus. Recombination had a major impact on the diversification of lineages. The genetic diversity assessed by the number of ST/strain was higher in low salinity conditions for V. parahaemolyticus and V. cholerae whereas the frequency of recombination events in V. cholerae was lower in low salinity. Mediterranean coastal lagoon systems housed V. cholerae and V. parahaemolyticus with genetic diversities equivalent to the worldwide diversity described so far. The presence of STs found in human infections as well as the frequency of recombination events in environmental vibrios populations could predict a potential epidemiological risk.

  18. Toxicological impact of cadmium-based quantum dots towards aquatic biota: Effect of natural sunlight exposure

    Energy Technology Data Exchange (ETDEWEB)

    Silva, B.F. [Department of Biology, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Andreani, T. [Centro de Investigação em Química da Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CITAB − Centre for Research and Technology of Agro-Environmental and Biological Sciences, University of Trás-os-Montes e Alto Douro, UTAD, Vila Real (Portugal); Gavina, A., E-mail: anacsgavina@gmail.com [Department of Biology, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Vieira, M.N. [Department of Biology, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Pereira, C.M. [Centro de Investigação em Química da Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); Rocha-Santos, T. [Department of Chemistry and Centre for Environmental and Marine Studies (CESAM), University of Aveiro, Campus de Santiago, 3810-193 Aveiro (Portugal); and others

    2016-07-15

    Highlights: • Under sunlight exposure, all QDs form particle aggregates in the different media. • CdSeS/ZnS QDs showed lower toxic effects to V. fischeri before sunlight exposure. • Sunlight exposure decreased the toxicity of CdS 480 in all organisms. • Sunlight exposure increased the toxicity of CdS 380 QDs for D. magna. • Shell of QDs seemed to make them less harmful to aquatic organisms. - Abstract: Cadmium-based quantum dots (QDs) are increasingly applied in existent and emerging technologies, especially in biological applications due to their exceptional photophysical and functionalization properties. However, they are very toxic compounds due to the high reactive and toxic cadmium core. The present study aimed to determine the toxicity of three different QDs (CdS 380, CdS 480 and CdSeS/ZnS) before and after the exposure of suspensions to sunlight, in order to assess the effect of environmentally relevant irradiation levels in their toxicity, which will act after their release to the environment. Therefore, a battery of ecotoxicological tests was performed with organisms that cover different functional and trophic levels, such as Vibrio fischeri, Raphidocelis subcapitata, Chlorella vulgaris and Daphnia magna. The results showed that core-shell type QDs showed lower toxic effects to V. fischeri in comparison to core type QDs before sunlight exposure. However, after sunlight exposure, there was a decrease of CdS 380 and CdS 480 QD toxicity to bacterium. Also, after sunlight exposure, an effective decrease of CdSeS/ZnS and CdS 480 toxicity for D. magna and R. subcapitata, and an evident increase in CdS 380 QD toxicity, at least for D. magna, were observed. The results of this study suggest that sunlight exposure has an effect in the aggregation and precipitation reactions of larger QDs, causing the degradation of functional groups and formation of larger bulks which may be less prone to photo-oxidation due to their diminished surface area. The same

  19. A pan-European ring trial to validate an International Standard for detection of Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus in seafoods.

    Science.gov (United States)

    Hartnell, R E; Stockley, L; Keay, W; Rosec, J-P; Hervio-Heath, D; Van den Berg, H; Leoni, F; Ottaviani, D; Henigman, U; Denayer, S; Serbruyns, B; Georgsson, F; Krumova-Valcheva, G; Gyurova, E; Blanco, C; Copin, S; Strauch, E; Wieczorek, K; Lopatek, M; Britova, A; Hardouin, G; Lombard, B; In't Veld, P; Leclercq, A; Baker-Austin, C

    2018-02-10

    Globally, vibrios represent an important and well-established group of bacterial foodborne pathogens. The European Commission (EC) mandated the Comite de European Normalisation (CEN) to undertake work to provide validation data for 15 methods in microbiology to support EC legislation. As part of this mandated work programme, merging of ISO/TS 21872-1:2007, which specifies a horizontal method for the detection of V. parahaemolyticus and V. cholerae, and ISO/TS 21872-2:2007, a similar horizontal method for the detection of potentially pathogenic vibrios other than V. cholerae and V. parahaemolyticus was proposed. Both parts of ISO/TS 21872 utilized classical culture-based isolation techniques coupled with biochemical confirmation steps. The work also considered simplification of the biochemical confirmation steps. In addition, because of advances in molecular based methods for identification of human pathogenic Vibrio spp. classical and real-time PCR options were also included within the scope of the validation. These considerations formed the basis of a multi-laboratory validation study with the aim of improving the precision of this ISO technical specification and providing a single ISO standard method to enable detection of these important foodborne Vibrio spp.. To achieve this aim, an international validation study involving 13 laboratories from 9 countries in Europe was conducted in 2013. The results of this validation have enabled integration of the two existing technical specifications targeting the detection of the major foodborne Vibrio spp., simplification of the suite of recommended biochemical identification tests and the introduction of molecular procedures that provide both species level identification and discrimination of putatively pathogenic strains of V. parahaemolyticus by the determination of the presence of theromostable direct and direct related haemolysins. The method performance characteristics generated in this have been included in revised

  20. Incidence of Vibrio cholerae and related vibrios in a coastal lagoon and seawater influenced by lake discharges along an annual cycle.

    Science.gov (United States)

    Garay, E; Arnau, A; Amaro, C

    1985-08-01

    Most probable numbers of Vibrio cholerae and related vibrios were determined in Albufera Lake, Valencia, Spain, and in coastal waters under the influence of the lake discharges over the course of an annual cycle. The influence of temperature, kind of water, and characteristics of the different sampling sites on the numbers of vibrios recovered was evaluated. Maximum recovery of vibrios reached 10(3)/ml in both types of waters analyzed. V. cholerae numbers reached 10(3)/ml in the lake and 10(2) in one of the coastal sites. Frequently during the warm season, all vibrios isolated were identified as V. cholerae. Occasionally, no V. cholerae was recovered. The recovery of vibrios was significantly influenced by the temperature of the water and the type of water analyzed. Most of the V. cholerae isolates were included in Heiberg groups I and II, and nearly 50% of the strains used chitin as sole carbon source. Indole was not produced by 100% of the strains. All strains tested were non-O1 serovars.

  1. Effects of Global Warming on Vibrio Ecology.

    Science.gov (United States)

    Vezzulli, Luigi; Pezzati, Elisabetta; Brettar, Ingrid; Höfle, Manfred; Pruzzo, Carla

    2015-06-01

    Vibrio-related infections are increasing worldwide both in humans and aquatic animals. Rise in global sea surface temperature (SST), which is approximately 1 °C higher now than 140 years ago and is one of the primary physical impacts of global warming, has been linked to such increases. In this chapter, major known effects of increasing SST on the biology and ecology of vibrios are described. They include the effects on bacterial growth rate, both in the field and in laboratory, culturability, expression of pathogenicity traits, and interactions with aquatic organisms and abiotic surfaces. Special emphasis is given to the effect of ocean warming on Vibrio interactions with zooplankters, which represent one of the most important aquatic reservoirs for these bacteria. The reported findings highlight the biocomplexity of the interactions between vibrios and their natural environment in a climate change scenario, posing the need for interdisciplinary studies to properly understand the connection between ocean warming and persistence and spread of vibrios in sea waters and the epidemiology of the diseases they cause.

  2. Identifying the cellular mechanisms of symbiont-induced epithelial morphogenesis in the squid-Vibrio association.

    Science.gov (United States)

    Koropatnick, Tanya; Goodson, Michael S; Heath-Heckman, Elizabeth A C; McFall-Ngai, Margaret

    2014-02-01

    The symbiotic association between the Hawaiian bobtail squid Euprymna scolopes and the luminous marine bacterium Vibrio fischeri provides a unique opportunity to study epithelial morphogenesis. Shortly after hatching, the squid host harvests bacteria from the seawater using currents created by two elaborate fields of ciliated epithelia on the surface of the juvenile light organ. After light organ colonization, the symbiont population signals the gradual loss of the ciliated epithelia through apoptosis of the cells, which culminates in the complete regression of these tissues. Whereas aspects of this process have been studied at the morphological, biochemical, and molecular levels, no in-depth analysis of the cellular events has been reported. Here we describe the cellular structure of the epithelial field and present evidence that the symbiosis-induced regression occurs in two steps. Using confocal microscopic analyses, we observed an initial epithelial remodeling, which serves to disable the function of the harvesting apparatus, followed by a protracted regression involving actin rearrangements and epithelial cell extrusion. We identified a metal-dependent gelatinolytic activity in the symbiont-induced morphogenic epithelial fields, suggesting the involvement of Zn-dependent matrix metalloproteinase(s) (MMP) in light organ morphogenesis. These data show that the bacterial symbionts not only induce apoptosis of the field, but also change the form, function, and biochemistry of the cells as part of the morphogenic program.

  3. The effect of lake sediment on the hatching success of Daphnia ephippial eggs

    Directory of Open Access Journals (Sweden)

    Jacek Radzikowski

    2016-07-01

    Full Text Available A large proportion of lake-Daphnia ephippia which are shed by females in the water column sink to the bottom, where they form an assemblage of dormant stages known as an egg bank. Although the quantity of zooplankton eggs in such assemblages may exceed tens of thousands per square meter, the annual hatch from this bank is usually extremely low (from zero to a few dozens animals per square meter per year. This low-hatching phenomenon may be caused by isolation from hatching stimuli by water or sediment layers, a mechanical barrier formed by sediment that does not allow hatchlings to reach the water, or by a bet-hedging strategy of the resting eggs. The aim of our study was to determine the extent to which coverage by lake sediment may affect the hatching of Daphnia dormant eggs. The ephippia of lake-Daphnia (longispina species complex, covered by sterilized lake sediment of different thicknesses (0, 0.25, 0.5, 1, 2 and 4 cm; 4 replicates per treatment, were incubated for 8 weeks in lab controlled conditions. The results indicate that even the thinnest tested layer (0.25 cm may completely inhibit hatching of ephippial eggs. A few Daphnia neonates were observed in two (of five sediment treatments, while dozens of animals hatched in the control one. In the second experiment we determined that the sediment sterilization process did not affect the hatching proportion of ephippial eggs (when compared to the treatment with unsterilized sediments. We hypothesize that the observed inhibition of Daphnia hatching in the main experiment, which may cause a serious problem for Cladoceran populations in lakes where no sediment mixing occurs, may be caused by low light intensity, anoxic conditions or a physical barrier created by the sediment.

  4. Standardized toxicity testing may underestimate ecotoxicity: Environmentally relevant food rations increase the toxicity of silver nanoparticles to Daphnia.

    Science.gov (United States)

    Stevenson, Louise M; Krattenmaker, Katherine E; Johnson, Erica; Bowers, Alexandra J; Adeleye, Adeyemi S; McCauley, Edward; Nisbet, Roger M

    2017-11-01

    Daphnia in the natural environment experience fluctuations in algal food supply, with periods when algal populations bloom and seasons when Daphnia have very little algal food. Standardized chronic toxicity tests, used for ecological risk assessment, dictate that Daphnia must be fed up to 400 times more food than they would experience in the natural environment (outside of algal blooms) for a toxicity test to be valid. This disconnect can lead to underestimating the toxicity of a contaminant. We followed the growth, reproduction, and survival of Daphnia exposed to 75 and 200 µg/L silver nanoparticles (AgNPs) at 4 food rations for up to 99 d and found that AgNP exposure at low, environmentally relevant food rations increased the toxicity of AgNPs. Exposure to AgNP at low food rations decreased the survival and/or reproduction of individuals, with potential consequences for Daphnia populations (based on calculated specific population growth rates). We also found tentative evidence that a sublethal concentration of AgNPs (75 µg/L) caused Daphnia to alter energy allocation away from reproduction and toward survival and growth. The present findings emphasize the need to consider resource availability, and not just exposure, in the environment when estimating the effect of a toxicant. Environ Toxicol Chem 2017;36:3008-3018. © 2017 SETAC. © 2017 SETAC.

  5. Mesozoic fossils (>145 Mya suggest the antiquity of the subgenera of Daphnia and their coevolution with chaoborid predators

    Directory of Open Access Journals (Sweden)

    Taylor Derek J

    2011-05-01

    Full Text Available Abstract Background The timescale of the origins of Daphnia O. F. Mueller (Crustacea: Cladocera remains controversial. The origin of the two main subgenera has been associated with the breakup of the supercontinent Pangaea. This vicariance hypothesis is supported by reciprocal monophyly, present day associations with the former Gondwanaland and Laurasia regions, and mitochondrial DNA divergence estimates. However, previous multilocus nuclear DNA sequence divergence estimates at Daphnia. Results We describe new fossils of ephippia from the Khotont site in Mongolia associated with the Jurassic-Cretaceous boundary (about 145 MYA that are morphologically similar to several modern genera of the family Daphniidae, including the two major subgenera of Daphnia, i.e., Daphnia s. str. and Ctenodaphnia. The daphniid fossils co-occurred with fossils of the predaceous phantom midge (Chaoboridae. Conclusions Our findings indicate that the main subgenera of Daphnia are likely much older than previously known from fossils (at least 100 MY older or from nuclear DNA estimates of divergence. The results showing co-occurrence of the main subgenera far from the presumed Laurasia/Gondwanaland dispersal barrier shortly after formation suggests that vicariance from the breakup of Pangaea is an unlikely explanation for the origin of the main subgenera. The fossil impressions also reveal that the coevolution of a dipteran predator (Chaoboridae with the subgenus Daphnia is much older than previously known -- since the Mesozoic.

  6. Vibrio elicits targeted transcriptional responses from copepod hosts.

    Science.gov (United States)

    Almada, Amalia A; Tarrant, Ann M

    2016-06-01

    Copepods are abundant crustaceans that harbor diverse bacterial communities, yet the nature of their interactions with microbiota are poorly understood. Here, we report that Vibrio elicits targeted transcriptional responses in the estuarine copepod Eurytemora affinis We pre-treated E. affinis with an antibiotic cocktail and exposed them to either a zooplankton specialist (Vibrio sp. F10 9ZB36) or a free-living species (Vibrio ordalii 12B09) for 24 h. We then identified via RNA-Seq a total of 78 genes that were differentially expressed following Vibrio exposure, including homologs of C-type lectins, chitin-binding proteins and saposins. The response differed between the two Vibrio treatments, with the greatest changes elicited upon inoculation with V. sp. F10 We suggest that these differentially regulated genes play important roles in cuticle integrity, the innate immune response, and general stress response, and that their expression may enable E. affinis to recognize and regulate symbiotic vibrios. We further report that V. sp. F10 culturability is specifically altered upon colonization of E. affinis These findings suggest that rather than acting as passive environmental vectors, copepods discriminately interact with vibrios, which may ultimately impact the abundance and activity of copepod-associated bacteria. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Aktivitas Antibakteri Ekstrak Buah Adas (Foeniculum vulgare, Mill) pada Vibrio harveyi dan Vibrio alginolyticus

    OpenAIRE

    Budianto, Budianto; Prajitno, Arief; Yuniarti, Ating

    2017-01-01

    Evaluation of natural products as a safe and effective antimicrobial agent is a scientific strategy to treat the drugresistant pathogens.Fennel(FoeniculumvulgareMill) is an herbal plant that has an active in gredient which is one of its benefit sasan antibacterial material. In thisstudy,water extract of fennel fruit determined the antibacterial activity against Vibrio harveyi and Vibrio alginolyticus using the minimum Inhibitory  Concentration Test (MIC) and paper disk diffusion method....

  8. Feeding response of Daphnia cf. similis to different concentration ...

    African Journals Online (AJOL)

    Bheema

    Experiments showing that Daphnia can suppress cyanobacteria in eutrophic lakes have been limited to cases ... Experimental Design, Sampling Method and Analysis ..... It may be also true in case of this study because high mortality of D. cf.

  9. Variation in copper effects on kairomone-mediated responses in Daphnia pulicaria.

    Science.gov (United States)

    DeMille, C M; Arnott, S E; Pyle, G G

    2016-04-01

    Chemical signals play an integral role in many predator-prey relationships but their effectiveness can be altered by environmental conditions. Prey species can detect predator kairomones, which induce anti-predator defenses. An example of this predator-prey relationship exists between Daphnia spp. and Chaoborus spp.; however, when living in water contaminated with low concentrations of copper (Cu) Daphnia can fail to respond to Chaoborus kairomone and, in turn, become more susceptible to predation. This has implications for Daphnia living in regions with Cu contamination, such as areas where mining activity has resulted in increased levels of metals in the surrounding lakes. We examined kairomone-mediated responses of multiple Daphnia pulicaria clones obtained from 8 lakes in Ontario, Canada, in the absence and presence of environmentally-relevant Cu concentrations. Life history traits and morphological anti-predator defenses were assessed using neonates collected from mothers that were exposed to kairomone and Cu treatments. We found that kairomone-mediated responses and Cu-tolerance varied among D. pulicaria clones. Clones exposed to kairomone, in the absence of Cu additions, had diverse responses, including larger neonates, delayed reproduction, or altered brood size relative to no-kairomone controls. These kairomone-induced responses act as antipredator defense strategies against Chaoborus by preventing predation or stabilizing population growth. When exposed to Cu, two clones were able to respond to kairomone, while four clones no longer induced a response to kairomone. This variation in non-lethal effects of Cu on aquatic organisms suggests that toxicity tests should incorporate multiple genotypes and include predator-prey interactions. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Ecotoxicological testing of gas oils (daphnia magna test)

    Energy Technology Data Exchange (ETDEWEB)

    Altmann, B.R.; Mueller, J.; Wenzel, A.; Hensel, R.

    2002-02-01

    The Water Accomodated Fractions WAF of 4 diesel fuels no. 2 and 4 domestic heating fuels no. 2 of differing origin were analysed on their effect on the mobility of the freshwater crustacean Daphnia Magna. Five loadings per test substance were tested. After an exposition period of 24 h a relationship between loading rates of the WAF and immobility was found for 3 samples, while after 48 h this was observed for all samples. WAF-generation and gas oil data were documented. (orig.) [German] Von 4 Dieselkraftstoff-Gasoelen und 4 Heizoel-Gasoelen EL wurden die Water Accomodated Fractions WAF auf ihre immobilisierende Wirkung auf den Wasserfloh Daphnia Magna untersucht. Von jeder Probe wurden fuenf unterschiedliche Dosierraten geprueft. Nach einer Expositionszeit von 24 Stunden zeigte sich bei 3 Proben und nach 48 Stunden bei allen Proben eine Beziehung zwischen der Dosierrate der Probe und der Immobilitaet. Die Herstellung der WAF und die Daten der Gasoele wurden dokumentiert. (orig.)

  11. Linear solvation energy relationships for toxicity of selected organic chemicals to Daphnia pulex and Daphnia magna

    Science.gov (United States)

    Passino, Dora R.M.; Hickey, James P.; Frank, Anthony M.

    1988-01-01

    In the Laurentian Great Lakes, more than 300 contaminants have been identified in fish, other biota, water, and sediment. Current hazard assessment of these chemicals by the National Fisheries Research Center-Great Lakes is based on their toxicity, occurrence in the environment, and source. Although scientists at the Center have tested over 70 chemicals with the crustacean Daphnia pulex, the number of experimental data needed to screen the huge array of chemicals in the Great Lakes exceeds the practical capabilities of conducting bioassays. This limitation can be partly circumvented, however, by using mathematical models based on quantitative structure-activity relationships (QSAR) to provide rapid, inexpensive estimates of toxicity. Many properties of chemicals, including toxicity, bioaccumulation and water solubility are well correlated and can be predicted by equations of the generalized linear solvation energy relationships (LSER). The equation we used to model solute toxicity is Toxicity = constant + mVI/100 + s (π* + dδ) + bβm + aαm where VI = intrinsic (Van der Waals) molar volume; π* = molecular dipolarity/polarizability; δ = polarizability 'correction term'; βm = solute hydrogen bond acceptor basicity; and αm = solute hydrogen bond donor acidity. The subscript m designates solute monomer values for α and β. We applied the LSER model to 48-h acute toxicity data (measured as immobilization) for six classes of chemicals detected in Great Lakes fish. The following regression was obtained for Daphnia pulex (concentration = μM): log EC50 = 4.86 - 4.35 VI/100; N = 38, r2 = 0.867, sd = 0.403 We also used the LSER modeling approach to analyze to a large published data set of 24-h acute toxicity for Daphnia magna; the following regression resulted, for eight classes of compounds (concentration = mM): log EC50 = 3.88 - 4.52 VI/100 - 1.62 π* + 1.66 βm - 0.916 αm; N = 62, r2 = 0.859, sd = 0.375 In addition we developed computer software that identifies

  12. A rapid bioassay for detecting saxitoxins using a Daphnia acute toxicity test.

    Science.gov (United States)

    Ferrão-Filho, Aloysio da S; Soares, Maria Carolina S; de Magalhães, Valéria Freitas; Azevedo, Sandra M F O

    2010-06-01

    Bioassays using Daphnia pulex and Moina micrura were designed to detect cyanobacterial neurotoxins in raw water samples. Phytoplankton and cyanotoxins from seston were analyzed during 15 months in a eutrophic reservoir. Effective time to immobilize 50% of the exposed individuals (ET50) was adopted as the endpoint. Paralysis of swimming movements was observed between approximately 0.5-3 h of exposure to lake water containing toxic cyanobacteria, followed by an almost complete recovery of the swimming activity within 24 h after being placed in control water. The same effects were observed in bioassays with a saxitoxin-producer strain of Cylindrospermopsis raciborskii isolated from the reservoir. Regression analysis showed significant relationships between ET50 vs. cell density, biomass and saxitoxins content, suggesting that the paralysis of Daphnia in lake water samples was caused by saxitoxins found in C. raciborskii. Daphnia bioassay was found to be a sensitive method for detecting fast-acting neurotoxins in natural samples, with important advantages over mouse bioassays. Copyright 2010 Elsevier Ltd. All rights reserved.

  13. Vibrio infections in Louisiana: twenty-five years of surveillance 1980-2005.

    Science.gov (United States)

    Thomas, Annu; Straif-Bourgeois, Susanne; Sokol, Theresa M; Ratard, Raoult C

    2007-01-01

    A total of 1,007 Vibrio infections were reported to the Infectious Disease Epidemiology Department at the Louisiana Office of Public Heath, between 1980 and 2005. The most common were Vibrio vulnificus (257 infections), Vibrio parahemolyticus (249 infections), and Vibrio cholerae non O1 (200 cases). Other species were much less common. Vibrio vulnificus infections, which are associated with consumption of raw seafood (particularly oysters) or contact with sea water, and severe immuno-suppression or liver disease were increasing. Septicemia and blood stream infections are the main manifestations of this infection. The number of infections due to Vibrio parahemolyticus on the other hand, causing mostly gastroenteritis, has remained stable. Vibrio cholerae infections are less common and almost always associated with consumption of partially cooked or contaminated crabs.

  14. Symbiotic bacteria contribute to increasing the population size of a freshwater crustacean, Daphnia magna.

    Science.gov (United States)

    Peerakietkhajorn, Saranya; Tsukada, Koji; Kato, Yasuhiko; Matsuura, Tomoaki; Watanabe, Hajime

    2015-04-01

    The filter-feeding crustacean Daphnia is a key organism in freshwater ecosystems. Here, we report the effect of symbiotic bacteria on ecologically important life history traits, such as population dynamics and longevity, in Daphnia magna. By disinfection of the daphniid embryos with glutaraldehyde, aposymbiotic daphniids were prepared and cultured under bacteria-free conditions. Removal of bacteria from the daphniids was monitored by quantitative polymerase chain reaction for bacterial 16S rRNA gene. The population of aposymbiotic daphniids was reduced 10-folds compared with that of the control daphniids. Importantly, re-infection with symbiotic bacteria caused daphniids to regain bacteria and increase their fecundity to the level of the control daphniids, suggesting that symbiotic bacteria regulate Daphnia fecundity. To identify the species of symbiotic bacteria, 16S rRNA genes of bacteria in daphniids were sequenced. This revealed that 50% of sequences belonged to the Limnohabitans sp. of the Betaproteobacteria class and that the diversity of bacterial taxa was relatively low. These results suggested that symbiotic bacteria have a beneficial effect on D. magna, and that aposymbiotic Daphnia are useful tools in understanding the role of symbiotic bacteria in the environmental responses and evolution of their hosts. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  15. Effects of Intertidal Harvest Practices on Levels of Vibrio parahaemolyticus and Vibrio vulnificus Bacteria in Oysters.

    Science.gov (United States)

    Jones, J L; Kinsey, T P; Johnson, L W; Porso, R; Friedman, B; Curtis, M; Wesighan, P; Schuster, R; Bowers, J C

    2016-08-01

    Vibrio parahaemolyticus and Vibrio vulnificus can grow rapidly in shellfish subjected to ambient air conditions, such as during intertidal exposure. In this study, levels of total and pathogenic (tdh(+) and/or trh(+)) V. parahaemolyticus and total V. vulnificus were determined in oysters collected from two study locations where intertidal harvest practices are common. Samples were collected directly off intertidal flats, after exposure (ambient air [Washington State] or refrigerated [New Jersey]), and after reimmersion by natural tidal cycles. Samples were processed using a most-probable-number (MPN) real-time PCR method for total and pathogenic V. parahaemolyticus or V. vulnificus In Washington State, the mean levels of V. parahaemolyticus increased 1.38 log MPN/g following intertidal exposure and dropped 1.41 log MPN/g after reimmersion for 1 day, but the levels were dependent upon the container type utilized. Pathogenic V. parahaemolyticus levels followed a similar trend. However, V. vulnificus levels increased 0.10 log MPN/g during intertidal exposure in Washington but decreased by >1 log MPN/g after reimmersion. In New Jersey, initial levels of all vibrios studied were not significantly altered during the refrigerated sorting and containerizing process. However, there was an increase in levels after the first day of reimmersion by 0.79, 0.72, 0.92, and 0.71 log MPN/g for total, tdh(+) and trh(+) V. parahaemolyticus, and V. vulnificus, respectively. The levels of all targets decreased to those similar to background after a second day of reimmersion. These data indicate that the intertidal harvest and handling practices for oysters that were studied in Washington and New Jersey do not increase the risk of illness from V. parahaemolyticus or V. vulnificus Vibrio parahaemolyticus and Vibrio vulnificus are the leading causes of seafood-associated infectious morbidity and mortality in the United States. Vibrio spp. can grow rapidly in shellfish subjected to ambient

  16. Liquid holding recovery and photoreactivation of the ultraviolet-inactivated vibrios

    International Nuclear Information System (INIS)

    Banerjee, S.K.; Chatterjee, S.N.

    1981-01-01

    The kinetics of liquid holding recovery and photoreactivation of the ultra-violet-inactivated vibrios have been investigated. Photoreactivation was highest (about 80%) for Vibrio cholerae (classical) strains but the liquid holding recovery was highest (about 29%) for Vibrio parahemolyticus ones. Significance of the differences between any two of the four vibrio biotypes in respect of their liquid holding recovery and also photoreactivation was analysed statistically. (auth.)

  17. Mesozoic fossils (>145 Mya) suggest the antiquity of the subgenera of Daphnia and their coevolution with chaoborid predators.

    Science.gov (United States)

    Kotov, Alexey A; Taylor, Derek J

    2011-05-19

    The timescale of the origins of Daphnia O. F. Mueller (Crustacea: Cladocera) remains controversial. The origin of the two main subgenera has been associated with the breakup of the supercontinent Pangaea. This vicariance hypothesis is supported by reciprocal monophyly, present day associations with the former Gondwanaland and Laurasia regions, and mitochondrial DNA divergence estimates. However, previous multilocus nuclear DNA sequence divergence estimates at Pangaea. We examined new and existing cladoceran fossils from a Mesozoic Mongolian site, in hopes of gaining insights into the timescale of the evolution of Daphnia. We describe new fossils of ephippia from the Khotont site in Mongolia associated with the Jurassic-Cretaceous boundary (about 145 MYA) that are morphologically similar to several modern genera of the family Daphniidae, including the two major subgenera of Daphnia, i.e., Daphnia s. str. and Ctenodaphnia. The daphniid fossils co-occurred with fossils of the predaceous phantom midge (Chaoboridae). Our findings indicate that the main subgenera of Daphnia are likely much older than previously known from fossils (at least 100 MY older) or from nuclear DNA estimates of divergence. The results showing co-occurrence of the main subgenera far from the presumed Laurasia/Gondwanaland dispersal barrier shortly after formation suggests that vicariance from the breakup of Pangaea is an unlikely explanation for the origin of the main subgenera. The fossil impressions also reveal that the coevolution of a dipteran predator (Chaoboridae) with the subgenus Daphnia is much older than previously known -- since the Mesozoic.

  18. Competitive outcome of Daphnia-Simocephalus experimental microcosms: salinity versus priority effects.

    Directory of Open Access Journals (Sweden)

    Cláudia Loureiro

    Full Text Available Competition is a major driving force in freshwaters, especially given the cyclic nature and dynamics of pelagic food webs. Competition is especially important in the initial species assortment during colonization and re-colonization events, which depends strongly on the environmental context. Subtle changes, such as saline intrusion, may disrupt competitive relationships and, thus, influence community composition. Bearing this in mind, our objective was to assess whether low salinity levels (using NaCl as a proxy alter the competitive outcome (measured as the rate of population biomass increase of Daphnia-Simocephalus experimental microcosms, taking into account interactions with priority effects (sequential species arrival order. With this approach, we aimed to experimentally demonstrate a putative mechanism of differential species sorting in brackish environments or in freshwaters facing secondary salinization. Experiments considered three salinity levels, regarding NaCl added (0.00, 0.75 and 1.50 g L(-1, crossed with three competition scenarios (no priority, priority of Daphnia over Simocephalus, and vice-versa. At lower NaCl concentrations (0.00 and 0.75 g L(-1, Daphnia was a significantly superior competitor, irrespective of the species inoculation order, suggesting negligible priority effects. However, the strong decrease in Daphnia population growth at 1.50 g L(-1 alleviated the competitive pressure on Simocephalus, causing an inversion of the competitive outcome in favour of Simocephalus. The intensity of this inversion depended on the competition scenario. This salinity-mediated disruption of the competitive outcome demonstrates that subtle environmental changes produce indirect effects in key ecological mechanisms, thus altering community composition, which may lead to serious implications in terms of ecosystem functioning (e.g. lake regime shifts due to reduced grazing and biodiversity.

  19. Making the Most of the "Daphnia" Heart Rate Lab: Optimizing the Use of Ethanol, Nicotine & Caffeine

    Science.gov (United States)

    Corotto, Frank; Ceballos, Darrel; Lee, Adam; Vinson, Lindsey

    2010-01-01

    Students commonly test the effects of chemical agents on the heart rate of the crustacean "Daphnia" magna, but the procedure has never been optimized. We determined the effects of three concentrations of ethanol, nicotine, and caffeine and of a control solution on heart rate in "Daphnia." Ethanol at 5% and 10% (v/v) reduced mean heart rate to…

  20. The influence of simulated microgravity on the proteome of Daphnia magna

    Data.gov (United States)

    National Aeronautics and Space Administration — Background/Objectives: The waterflea Daphnia is an interesting candidate for bioregenerative life support systems (BLSS). These animals are particularly promising...

  1. Genomic integration and germline transmission of plasmid injected into crustacean Daphnia magna eggs.

    Directory of Open Access Journals (Sweden)

    Yasuhiko Kato

    Full Text Available The water flea, Daphnia, has been the subject of study in ecology, evolution, and environmental sciences for decades. Over the last few years, expressed sequence tags and a genome sequence have been determined. In addition, functional approaches of overexpression and gene silencing based on microinjection of RNAs into eggs have been established. However, the transient nature of these approaches prevents us from analyzing gene functions in later stages of development. To overcome this limitation, transgenesis would become a key tool. Here we report establishment of a transgenic line using microinjection of plasmid into Daphnia magna eggs. The green fluorescent protein (GFP gene fused with the D. magna histone H2B gene under the control of a promoter/enhancer region of the elongation factor 1α-1 (EF1α-1 gene, EF1α-1::H2B-GFP, was used as a reporter providing high resolution visualization of active chromatin. Transgenic lines were obtained from 0.67% of the total fertile adults that survived the injections. One of the transgenic animals, which exhibited fluorescence in the nuclei of cells during embryogenesis and oogenesis, had two copies of EF1α-1::H2B-GFP in a head-to-tail array. This is the first report of a transgenesis technique in Daphnia and, together with emerging genome sequences, will be useful for advancing knowledge of the molecular biology of Daphnia.

  2. Medical-biological aspects of radiation effects in Daphnia magna

    International Nuclear Information System (INIS)

    Sarapultseva, E; Ustenko, K; Uskalova, D; Savina, N

    2017-01-01

    We have shown that γ-irradiation at doses of 100 and 1000 mGy significantly compromised fecundity and reproductive success of the directly exposed D. magna . These effects were also observed among the non-exposed first-generation progeny of irradiated parents, thus implying the manifestation of transgenerational effects in Daphnia . We have also shown that compromised viability of irradiated D. magna can be attributed cytotoxic effects of irradiation. It would therefore appear that the compromised viability may be attributed to the cytotoxic effects resulted from epigenetic changes affecting some metabolic pathways involved in detoxification of free-radicals. Additionally we have analyzed more distant progeny of irradiated at doses of 10, 100 and 1000 mGy Daphnia . Our data demonstrated that multicellular crustacean D. magna represent a very useful experimental model for analyse of long-term effects of ionising radiation at the organismal level. (paper)

  3. Saharan dust nutrients promote Vibrio bloom formation in marine surface waters.

    Science.gov (United States)

    Westrich, Jason R; Ebling, Alina M; Landing, William M; Joyner, Jessica L; Kemp, Keri M; Griffin, Dale W; Lipp, Erin K

    2016-05-24

    Vibrio is a ubiquitous genus of marine bacteria, typically comprising a small fraction of the total microbial community in surface waters, but capable of becoming a dominant taxon in response to poorly characterized factors. Iron (Fe), often restricted by limited bioavailability and low external supply, is an essential micronutrient that can limit Vibrio growth. Vibrio species have robust metabolic capabilities and an array of Fe-acquisition mechanisms, and are able to respond rapidly to nutrient influx, yet Vibrio response to environmental pulses of Fe remains uncharacterized. Here we examined the population growth of Vibrio after natural and simulated pulses of atmospherically transported Saharan dust, an important and episodic source of Fe to tropical marine waters. As a model for opportunistic bacterial heterotrophs, we demonstrated that Vibrio proliferate in response to a broad range of dust-Fe additions at rapid timescales. Within 24 h of exposure, strains of Vibrio cholerae and Vibrio alginolyticus were able to directly use Saharan dust-Fe to support rapid growth. These findings were also confirmed with in situ field studies; arrival of Saharan dust in the Caribbean and subtropical Atlantic coincided with high levels of dissolved Fe, followed by up to a 30-fold increase of culturable Vibrio over background levels within 24 h. The relative abundance of Vibrio increased from ∼1 to ∼20% of the total microbial community. This study, to our knowledge, is the first to describe Vibrio response to Saharan dust nutrients, having implications at the intersection of marine ecology, Fe biogeochemistry, and both human and environmental health.

  4. Characterization of the cell polarity gene crumbs during the early development and maintenance of the squid-vibrio light organ symbiosis.

    Science.gov (United States)

    Peyer, Suzanne M; Heath-Heckman, Elizabeth A C; McFall-Ngai, Margaret J

    2017-11-01

    The protein Crumbs is a determinant of apical-basal cell polarity and plays a role in apoptosis of epithelial cells and their protection against photodamage. Using the squid-vibrio system, a model for development of symbiotic partnerships, we examined the modulation of the crumbs gene in host epithelial tissues during initiation and maintenance of the association. The extracellular luminous symbiont Vibrio fischeri colonizes the apical surfaces of polarized epithelia in deep crypts of the Euprymna scolopes light organ. During initial colonization each generation, symbiont harvesting is potentiated by the biochemical and biophysical activity of superficial ciliated epithelia, which are several cell layers from the crypt epithelia where the symbionts reside. Within hours of crypt colonization, the symbionts induce the cell death mediated regression of the remote superficial ciliated fields. However, the crypt cells directly interacting with the symbiont are protected from death. In the squid host, we characterized the gene and encoded protein during light organ morphogenesis and in response to symbiosis. Features of the protein sequence and structure, phylogenetic relationships, and localization patterns in the eye supported assignment of the squid protein to the Crumbs family. In situ hybridization revealed that the crumbs transcript shows opposite expression at the onset of symbiosis in the two different regions of the light organ: elevated levels in the superficial epithelia were attenuated whereas low levels in the crypt epithelia were turned up. Although a rhythmic association in which the host controls the symbiont population over the day-night cycle begins in the juvenile upon colonization, cycling of crumbs was evident only in the adult organ with peak expression coincident with maximum symbiont population and luminescence. Our results provide evidence that crumbs responds to symbiont cues that induce developmental apoptosis and to symbiont population

  5. Examples of sediment assessment on the Elbe: contamination and ecotoxic effect; Beispiele der Sedimentbewertung an der Elbe: Schadstoffbelastung und oekotoxische Wirkung

    Energy Technology Data Exchange (ETDEWEB)

    Claus, E.; Heininger, P.; Pfitzner, S. [Bundesanstalt fuer Gewaesserkunde, Berlin (Germany)

    2000-11-01

    It is now an undisputed fact that comprehensive sediment assessment is only possible through a combination of chemical studies on contamination, ecotoxicological tests and in situ studies. The effect of chemicals on the aquatic environment can be determined in the sediment itself and in the derived compartments. The batteries of biotests proposed for this purpose and also used for Elbe sediments encompass studies on the whole sediment, in the elutriate and in extracts with methanol. The test battery presented here is more extensive and also includes pore water studies. For the tests with the whole sediment, the following test organisms were used: D. magna (DA), C. riparius (CR), T. tubifex (TT), B. cereus (BC) and C. elegans (NE). The toxic effect of pore waters and elutriates were tested with daphnia, green algae (Scenedesmus subspicatus) and luminescent bacteria (Vibrio fischeri). Luminescent bacteria alone were used for the ecotoxicological study. For this studies eight fresh sediment samples were selected from one reference site Alte Elbe (AE, km 252) and the two anthropogenic influenced sampling sites Meissen harbour (HM, km 83.2) and Fahlberg-List Magdeburg (FL, km 319.4) on the Elbe and the reference site Freienbrink (FB, km 21.5) on the Spree (Fig. 1). The samples were taken in June and October 1997. (orig.) [German] Mittlerweile unbestritten ist die Tatsache, dass nur die Kombination aus chemischen Untersuchungen zur Schadstoffbelastung, oekotoxikologischen Tests und in situ-Untersuchungen eine umfassende Sedimentbewertung moeglich macht. Die Wirkung von Chemikalien auf die aquatische Umwelt laesst sich im Sediment selbst und in daraus abgeleiteten Kompartimenten nachweisen. Fuer den Zweck vorgeschlagene und auch auf Elbe-Sedimente angewandte Batterien von Biotests umfassen Untersuchungen im Gesamtsediment, im Eluat und in Extrakten mit Methanol. Die hier vorgestellte Testbatterie ist umfangreicher und um Porenwasseruntersuchungen erweitert worden. Fuer

  6. وقوع ویبریوز بیماریزا در مناطق ساحلی استان گلستان ایران

    Directory of Open Access Journals (Sweden)

    ه. فروهش

    2005-02-01

    Full Text Available This study was carried out to investigate the occurrence of potentially pathogenic species of vibrio in sea water and estuarine environments of the Caspian Sea in the Golestan province of Iran. A total of 127 water samples from coastal waters as well as from river and estuaries were collected and analyzed by culture, during April and September 2001. Following prompt centrifugation, the resuspended sediments were initially enriched in alkaline peptone water and subsequently plated onto selective media including thiosulphate-citrate-bile salts-sucrose. Presumptive vibrio colonies were isolated and identified to species level using a gallery of biochemical and differential tests. In this study, Vibrio vulnificus was the predominant species isolated from sea waters (41%, followed by Vibrio parahaemolyticus (33%, Vibrio alginolyticus (15%, Vibrio fischeri (5%, Vibrio natriegens (4%, Vibrio damsela (0.7%, and Vibrio harveyi (0.7%. Non-01 Vibrio cholerae was the most abundant vibrio species recovered from fresh surface waters (80% of the total isolates. Five Vibrio Cholerae 01 species isolated, all belonging to Ogawa serogroups, were also recovered from the estuaries. The results of this study demonstrated the presence of pathogenic vibrio species in Caspian sea and coastal waters. The potential sanitary risk associated with the presence of these bacteria in the aquatic environment emphasizes the necessity of long-term monitoring programs.

  7. Multigenerational cadmium acclimation and biokinetics in Daphnia magna

    International Nuclear Information System (INIS)

    Guan Rui; Wang Wenxiong

    2006-01-01

    A Cd exposure (3 μg L -1 ) experiment was conducted for six successive generations to investigate the responses to chronic Cd stress in Daphnia magna. We observed a biphasic accumulation of Cd in the six generations and suggested a similar pattern with respect to daphnids' tolerance. Cd assimilation efficiencies, daphnid growth, and reproduction corresponded to the changes of tolerance, which was partially accounted for by metallothionein induction. When maternally exposed neonates grew in Cd-free water for one or two generations, their growth, MT concentration and biokinetic parameters partially or totally recovered. The rapid recovery suggests the high potential for ecological restoration from Cd pollution. Our results indicate that the tolerance of sensitive D. magna clones to Cd was dependent on long-term or multigenerational exposure. The tolerance developed within the first several generations might not be maintained, and the animals may become even more sensitive to Cd stress in subsequent generations. - Tolerance of sensitive Daphnia magna clones to cadmium was dependent on long-term or multigenerational exposure

  8. The acute toxic effects of 1-alkyl-3-methylimidazolium nitrate ionic liquids on Chlorella vulgaris and Daphnia magna.

    Science.gov (United States)

    Zhang, Cheng; Zhang, Shuai; Zhu, Lusheng; Wang, Jinhua; Wang, Jun; Zhou, Tongtong

    2017-10-01

    Given their increasingly widespread application, the toxic effects of ionic liquids (ILs) have become the subject of significant attention in recent years. Therefore, the present study assessed the acute toxic effects of 1-alkyl-3-methylimidazolium nitrate ([C n mim]NO 3 (n = 2, 4, 6, 8, 10, 12)) on Chlorella vulgaris and Daphnia magna. The sensitivity of the tested organism Daphnia magna and the investigated IL concentrations in water using high-performance liquid chromatography (HPLC) were also evaluated to demonstrate the reliability of the present study. The results illustrated that Daphnia magna is indeed sensitive to the reference toxicant and the investigated ILs were stable in the aquatic environment. The 50% effect concentration (EC 50 ) was used to represent the acute toxic effects on Chlorella vulgaris and Daphnia magna. With the increasing alkyl-chain lengths, the toxicity of the investigated ILs increased in both the test organisms. Accordingly, the alkyl-chain lengths can cause significantly toxic effects on aquatic organisms, and Daphnia magna are much more sensitive than Chlorella vulgaris to the imidazolium-based ILs used in the present study. Furthermore, the present study provides more information on the acute toxic effects of 1-alkyl-3-methylimidazolium nitrate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Dopamine is a key regulator in the signalling pathway underlying predator-induced defences in Daphnia

    Science.gov (United States)

    Weiss, Linda C.; Leese, Florian; Laforsch, Christian; Tollrian, Ralph

    2015-01-01

    The waterflea Daphnia is a model to investigate the genetic basis of phenotypic plasticity resulting from one differentially expressed genome. Daphnia develops adaptive phenotypes (e.g. morphological defences) thwarting predators, based on chemical predator cue perception. To understand the genomic basis of phenotypic plasticity, the description of the precedent cellular and neuronal mechanisms is fundamental. However, key regulators remain unknown. All neuronal and endocrine stimulants were able to modulate but not induce defences, indicating a pathway of interlinked steps. A candidate able to link neuronal with endocrine responses is the multi-functional amine dopamine. We here tested its involvement in trait formation in Daphnia pulex and Daphnia longicephala using an induction assay composed of predator cues combined with dopaminergic and cholinergic stimulants. The mere application of both stimulants was sufficient to induce morphological defences. We determined dopamine localization in cells found in close association with the defensive trait. These cells serve as centres controlling divergent morphologies. As a mitogen and sclerotization agent, we anticipate that dopamine is involved in proliferation and structural formation of morphological defences. Furthermore, dopamine pathways appear to be interconnected with endocrine pathways, and control juvenile hormone and ecdysone levels. In conclusion, dopamine is suggested as a key regulator of phenotypic plasticity. PMID:26423840

  10. Low temperature and Daphnia-associated infochemicals promote colony formation of Scenedesmus obliquus and its harvesting.

    Science.gov (United States)

    Zhu, Xuexia; Yang, Jingwen; Zhang, Xingxing; Zhang, Lu; Wang, Xiaojun; Huang, Yuan; Yang, Zhou

    2017-01-01

    To explore the combined effects of temperature and Daphnia-associated infochemicals on colony formation of Scenedesmus obliquus to faciliate harvesting the algal biomass. A three-parameter modified Gaussian model fitted the changes of the number of cells per particle in S. obliquus induced by Daphnia culture filtrate well under any temperature. Decreases in temperature enhanced the induced-colony formation of Scenedesmus. The maximum colony size at 15-25 °C was significantly larger than those at 30-35 °C. An additional 1 or 2 days at low temperature was needed to reach the maximum colony size, which indicates the best harvest time for algal biomass. Induced-colony formation of Scenedesmus by Daphnia culture filtrate at 15-25 °C is recommended to settle algal cells. This condition facilitates harvesting the biomass.

  11. Uptake and depuration of gold nanoparticles in Daphnia magna

    DEFF Research Database (Denmark)

    Skjolding, Lars Michael; Kern, Kristina; Hjorth, Rune

    2014-01-01

    This study presents a series of short-term studies (total duration 48 h) of uptake and depuration of engineered nanoparticles (ENP) in neonate Daphnia magna. Gold nanoparticles (Au NP) were used to study the influence of size, stabilizing agent and feeding on uptake and depuration kinetics...

  12. Bleach Solution Requirement for Hatching of Daphnia magna Resting Eggs

    Directory of Open Access Journals (Sweden)

    Catur Retnaningdyah

    2016-11-01

    Full Text Available Daphnia (water fleas belong to the zooplankton group called Cladocerans have sexual reproduction when conditions less favorable that produce diapausing eggs are enclosed in the ephippium. Hatching ephippial eggs in the laboratory is important in ecological, toxicology, genetical, and evolutionary studies. This study aims to improve the current methods of egg hatching from ephippium. Each of 50 ephippium were treated together by placing them in a glass jar and adding 50 mL bleach solution (sodium hypochlorite. Concentrations of sodium hypochlorite used in this experiment were 0%, 0.5%, 1%, 2%, 4% and 8%. These concentration treatments were crossed with the following exposure times (1, 2, 4, 8, 16, and 32 minutes. Culturing was done in 80 mL of artificial Daphnia medium, incubated in constant light and temperatures 20°C for 25 days. There were two repetitions in this experiment that were run at the same time. Result of this experiment showed that pretreatment with 0.5-8% bleach solution significantly increases the yield of total hatch rate of Daphnia magna resting eggs by about 21% over unbleached control. However, there was no significant difference among the bleach treatments. Concentration of bleach solution 0.5%, 1% and 4% significantly accelerated the time period until the first hatching (first day hatching. Difference of exposure time (1 - 32 minutes at each concentration treatments were not influence the yield of total hatch and the time period until first hatching.

  13. Identification of intermediates and assessment of ecotoxicity in the oxidation products generated during the ozonation of clofibric acid.

    Science.gov (United States)

    Rosal, Roberto; Gonzalo, María S; Boltes, Karina; Letón, Pedro; Vaquero, Juan J; García-Calvo, E

    2009-12-30

    The degradation of an aqueous solution of clofibric acid was investigated during catalytic and non-catalytic ozonation. The catalyst, TiO(2), enhanced the production of hydroxyl radicals from ozone and raised the fraction or clofibric acid degraded by hydroxyl radicals. The rate constant for the reaction of clofibric acid and hydroxyl radicals was not affected by the presence of the catalyst. The toxicity of the oxidation products obtained during the reaction was assessed by means of Vibrio fischeri and Daphnia magna tests in order to evaluate the potential formation of toxic by-products. The results showed that the ozonation was enhanced by the presence of TiO(2,) the clofibric acid being removed completely after 15 min at pH 5. The evolution of dissolved organic carbon, specific ultraviolet absorption at 254 nm and the concentration of carboxylic acids monitored the degradation process. The formation of 4-chlorophenol, hydroquinone, 4-chlorocatechol, 2-hydroxyisobutyric acid and three non-aromatic compounds identified as a product of the ring-opening reaction was assessed by exact mass measurements performed by liquid chromatography coupled to time-of-flight mass spectrometry (LC-TOF-MS). The bioassays showed a significant increase in toxicity during the initial stages of ozonation following a toxicity pattern closely related to the formation of ring-opening by-products.

  14. Photocatalytic treatment of pharmaceutical wastewater using new multiwall-carbon nanotubes/TiO{sub 2}/SiO{sub 2} nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Czech, Bożena, E-mail: bczech@hektor.umcs.lublin.pl [Department of Environmental Chemistry, Faculty of Chemistry, Maria Curie-Skłodowska University, Lublin (Poland); Buda, Waldemar [Department of Adsorption, Faculty of Chemistry, Maria Curie-Skłodowska University, Lublin (Poland)

    2015-02-15

    For the photocatalytic removal of bisphenol A (BPA) and carbamazepine (CBZ) from water solution a new multiwall-carbon nanotubes and TiO{sub 2}/SiO{sub 2} nanocomposites (MWCNT–TiO{sub 2}–SiO{sub 2}) were applied. Nanocomposites with the addition of 0.15–17.8 wt% MWCNT show high potential for the removal of both pollutants. The starting concentration of each contaminant was halved during 20 min of UVA irradiation. The decomposition process of CBZ over investigated nanocomposites proceeded differently than it was observed for the classical photocatalyst P25. The kinetics of the removal followed as a pseudo-first order regime with the k{sub 1} in range 0.0827–0.1751 min{sup −1} for BPA and 0.0131–0.0743 min{sup −1} for CBZ. Toxicity to Vibrio fischeri and Daphnia magna was significantly reduced indicating formation of non-toxic products of photooxidation of tested contaminants. - Highlights: • MWCNT enhanced TiO{sub 2} activity in UVA and the removal of BPA and CBZ. • At least 50% PPCPs removal during 30 min of photocatalytic treatment was observed. • MWCNT changed the mechanism of CBZ decomposition but not BPA. • Decomposition products of both BPA and CBZ possessed low toxicity. • Photocatalysis may be recommended for the initial treatment of pharmaceutical wastewater.

  15. Single nucleotide polymorphism discovery from expressed sequence tags in the waterflea Daphnia magna

    Directory of Open Access Journals (Sweden)

    Souche Erika L

    2011-06-01

    Full Text Available Abstract Background Daphnia (Crustacea: Cladocera plays a central role in standing aquatic ecosystems, has a well known ecology and is widely used in population studies and environmental risk assessments. Daphnia magna is, especially in Europe, intensively used to study stress responses of natural populations to pollutants, climate change, and antagonistic interactions with predators and parasites, which have all been demonstrated to induce micro-evolutionary and adaptive responses. Although its ecology and evolutionary biology is intensively studied, little is known on the functional genomics underpinning of phenotypic responses to environmental stressors. The aim of the present study was to find genes expressed in presence of environmental stressors, and target such genes for single nucleotide polymorphic (SNP marker development. Results We developed three expressed sequence tag (EST libraries using clonal lineages of D. magna exposed to ecological stressors, namely fish predation, parasite infection and pesticide exposure. We used these newly developed ESTs and other Daphnia ESTs retrieved from NCBI GeneBank to mine for SNP markers targeting synonymous as well as non synonymous genetic variation. We validate the developed SNPs in six natural populations of D. magna distributed at regional scale. Conclusions A large proportion (47% of the produced ESTs are Daphnia lineage specific genes, which are potentially involved in responses to environmental stress rather than to general cellular functions and metabolic activities, or reflect the arthropod's aquatic lifestyle. The characterization of genes expressed under stress and the validation of their SNPs for population genetic study is important for identifying ecologically responsive genes in D. magna.

  16. A peroxidase related to the mammalian antimicrobial protein myeloperoxidase in the Euprymna-Vibrio mutualism.

    Science.gov (United States)

    Weis, V M; Small, A L; McFall-Ngai, M J

    1996-11-26

    Many animal-bacteria cooperative associations occur in highly modified host organs that create a unique environment for housing and maintaining the symbionts. It has been assumed that these specialized organs develop through a program of symbiosis-specific or -enhanced gene expression in one or both partners, but a clear example of this process has been lacking. In this study, we provide evidence for the enhanced production of an enzyme in the symbiotic organ of the squid Euprymna scolopes, which harbors a culture of the luminous bacterium Vibrio fischeri. Our data show that this enzyme has a striking biochemical similarity to mammalian myeloperoxidase (MPO; EC 1.11.17), an antimicrobial dianisidine peroxidase that occurs in neutrophils. MPO and the squid peroxidase catalyze the same reaction, have similar apparent subunit molecular masses, and a polyclonal antibody to native human MPO specifically localized a peroxidase-like protein to the bacteria-containing regions of the symbiotic organ. We also provide evidence that a previously described squid cDNA encodes the protein (LO4) that is responsible for the observed dianisidine peroxidase activity. An antibody made against a fragment of LO4 immunoprecipiated dianisidine peroxidase activity from extracts of the symbiotic organ, and reacted against these extracts and human MPO in Western blot analysis. These data suggest that related biochemical mechanisms for the control of bacterial number and growth operate in associations that are as functionally diverse as pathogenesis and mutualism, and as phylogenetically distant as molluscs and mammals.

  17. Acute and chronic toxicity of veterinary antibiotics to Daphnia magna

    DEFF Research Database (Denmark)

    Wollenberger, Leah; Halling-Sørensen, B.; Kusk, Kresten Ole

    2000-01-01

    The acute and chronic toxicity of nine antibiotics used both therapeutically and as growth promoters in intensive farming was investigated on the freshwater crustacean Daphnia magna. The effect of the antibiotics metronidazole (M), olaquindox (OL), oxolinic acid (OA), oxytetracycline (OTC...

  18. AN INVESTIGATION ON PATHOGENIC VIBRIOS DISTRIBUTION IN DOMESTIC WASTEWATER

    OpenAIRE

    A. Almasi

    2005-01-01

    Municipal wastewater is one of the most important pollution sources for water supply resources. Identification and enumeration of pathogenic agents particularly pathogenic Vibrios are beneficial for controlling and prevention planning of the infectious diseases. This research was carried out to identify the distribution of the recognized pathogenic Vibrios with emphasizing on identification of Vibrio cholera in the wastewater of Kermanshah city western Iran in 2002. The method of study was cr...

  19. Do microplastic particles affect Daphnia magna at the morphological, life history and molecular level?

    Directory of Open Access Journals (Sweden)

    Hannes K Imhof

    Full Text Available Microplastic particles are ubiquitous not only in marine but also in freshwater ecosystems. However, the impacts of microplastics, consisting of a large variety of synthetic polymers, on freshwater organisms remains poorly understood. We examined the effects of two polymer mixtures on the morphology, life history and on the molecular level of the waterflea Daphnia magna (three different clones. Microplastic particles of ~40 μm were supplied at a low concentration (1% of the food particles leading to an average of ~30 particles in the digestive tract which reflects a high microplastic contamination but still resembles a natural situation. Neither increased mortality nor changes on the morphological (body length, width and tail spine length or reproductive parameters were observed for adult Daphnia. The analyses of juvenile Daphnia revealed a variety of small and rather subtle responses of morphological traits (body length, width and tail spine length. For adult Daphnia, alterations in expression of genes related to stress responses (i.e. HSP60, HSP70 & GST as well as of other genes involved in body function and body composition (i.e. SERCA were observed already 48h after exposure. We anticipate that the adverse effects of microplastic might be influenced by many additional factors like size, shape, type and even age of the particles and that the rather weak effects, as detected in a laboratory, may lead to reduced fitness in a natural multi-stressor environment.

  20. Genetic architecture of resistance in Daphnia hosts against two species of host-specific parasites.

    Science.gov (United States)

    Routtu, J; Ebert, D

    2015-02-01

    Understanding the genetic architecture of host resistance is key for understanding the evolution of host-parasite interactions. Evolutionary models often assume simple genetics based on few loci and strong epistasis. It is unknown, however, whether these assumptions apply to natural populations. Using a quantitative trait loci (QTL) approach, we explore the genetic architecture of resistance in the crustacean Daphnia magna to two of its natural parasites: the horizontally transmitted bacterium Pasteuria ramosa and the horizontally and vertically transmitted microsporidium Hamiltosporidium tvaerminnensis. These two systems have become models for studies on the evolution of host-parasite interactions. In the QTL panel used here, Daphnia's resistance to P. ramosa is controlled by a single major QTL (which explains 50% of the observed variation). Resistance to H. tvaerminnensis horizontal infections shows a signature of a quantitative trait based in multiple loci with weak epistatic interactions (together explaining 38% variation). Resistance to H. tvaerminnensis vertical infections, however, shows only one QTL (explaining 13.5% variance) that colocalizes with one of the QTLs for horizontal infections. QTLs for resistance to Pasteuria and Hamiltosporidium do not colocalize. We conclude that the genetics of resistance in D. magna are drastically different for these two parasites. Furthermore, we infer that based on these and earlier results, the mechanisms of coevolution differ strongly for the two host-parasite systems. Only the Pasteuria-Daphnia system is expected to follow the negative frequency-dependent selection (Red Queen) model. How coevolution works in the Hamiltosporidium-Daphnia system remains unclear.

  1. Effects of ambient exposure, refrigeration, and icing on Vibrio vulnificus and Vibrio parahaemolyticus abundances in oysters.

    Science.gov (United States)

    Jones, J L; Lydon, K A; Kinsey, T P; Friedman, B; Curtis, M; Schuster, R; Bowers, J C

    2017-07-17

    Vibrio vulnificus (Vv) and V. parahaemolyticus (Vp) illnesses are typically acquired through the consumption of raw molluscan shellfish, particularly oysters. As Vibrio spp. are naturally-occurring bacteria, one means of mitigation of illness is achieved by limiting post-harvest growth. In this study, effects of ambient air storage, refrigeration, and icing of oysters on Vibrio spp. abundances were examined at two sites in Alabama (AL) [Dog River (DR) and Cedar Point (CP)] and one site in Delaware Bay, New Jersey (NJ). As the United States shellfish program recommendations include testing for total these organisms and gene targets, Vv and total (tlh) and pathogenic (tdh+ and trh+) Vp were enumerated from samples using MPN-real-time-PCR approaches. Mean Vv and Vp abundances in oysters from AL-DR were lowest in immediately iced samples (2.3 and -0.1 log MPN/g, respectively) and highest in the 5h ambient then refrigerated samples (3.4 and 0.5 log MPN/g, respectively). Similarly, in AL-CP Vv and Vp mean levels in oysters were lowest in immediately iced samples (3.6 and 1.2 log MPN/g, respectively) and highest in 5h ambient then refrigerated samples (5.1 and 3.2 log MPN/g, respectively). Mean levels of pathogenic Vp from AL sites were frequently below the limit of detection (oysters were highest in samples which were held for 7h in the shade (5.3 and 4.8 log MPN/g, respectively). Mean pathogenic Vp levels in oysters at initial harvest were also highest in oysters 7h in the shade (2.1 and 2.2 log MPN/g for tdh+ and trh+ Vp). Regardless of sampling location, Vibrio spp. levels were generally significantly (poysters exposed to 5h of air storage compared to the initially harvested samples. In addition, the data demonstrated that the use of layered ice resulted in lower Vibrio spp. levels in oysters, compared to those that were refrigerated post-harvest. These results suggest vibriosis risk can be mitigated by shorter storage times and more rapid cooling of oysters

  2. Neckteeth formation in two species of the Daphnia curvirostris complex (Crustacea: Cladocera

    Directory of Open Access Journals (Sweden)

    Petr Jan JURAČKA

    2011-08-01

    Full Text Available Cladocerans of the genus Daphnia show different morphological adaptations against invertebrate predation. Among those, the formation of neckteeth has attracted substantial attention. Morphotypes exhibiting neckteeth better resist predation from larvae of phantom midges Chaoborus (Diptera. These morphological structures are known from several species of the Daphnia longispina and D. pulex complexes; recently they have also been reported in the D. curvirostris complex, within which they are well documented from the Far East species D. sinevi and from Central European D. hrbaceki. Much scarcer are indications of the formation of these structures in the widespread species D. curvirostris. Careful inspection of samples from pools with Chaoborus larvae nevertheless revealed that a small necktooth in the first few instars of D. curvirostris is not uncommon, but probably has been mostly overlooked in the past. Occasionally, even adult D. curvirostris males may carry this feature. We provide documentation, particularly by scanning electron micrographs, of neckteeth in field-collected D. curvirostris, and in juvenile individuals of its sister species D. hrbaceki. In addition, we tested the response of three clones each of D. curvirostris and D. hrbaceki to Chaoborus kairomones in laboratory experiments. Two clones of the former species and all three of the latter responded to this predator cue with neckteeth formation. First-instar juveniles of D. hrbaceki also occasionally carried neckteeth in control treatments without Chaoborus kairomones, but second and third instars did not. We also observed strong interclonal variation in neonate length in the presence of kairomones in this species. We provide a summary table listing all Daphnia species presently known to exhibit neckteeth, and propose that the ability to form these structures may be more widespread among common Daphnia species than previously assumed.

  3. Relationship of the luminous bacterial symbiont of the Caribbean flashlight fish, Kryptophanaron alfredi (family Anomalopidae) to other luminous bacteria based on bacterial luciferase (luxA) genes.

    Science.gov (United States)

    Haygood, M G

    1990-01-01

    Flashlight fishes (family Anomalopidae) have light organs that contain luminous bacterial symbionts. Although the symbionts have not yet been successfully cultured, the luciferase genes have been cloned directly from the light organ of the Caribbean species, Kryptophanaron alfredi. The goal of this project was to evaluate the relationship of the symbiont to free-living luminous bacteria by comparison of genes coding for bacterial luciferase (lux genes). Hybridization of a lux AB probe from the Kryptophanaron alfredi symbiont to DNAs from 9 strains (8 species) of luminous bacteria showed that none of the strains tested had lux genes highly similar to the symbiont. The most similar were a group consisting of Vibrio harveyi, Vibrio splendidus and Vibrio orientalis. The nucleotide sequence of the luciferase alpha subunit gene luxA) of the Kryptophanaron alfredi symbiont was determined in order to do a more detailed comparison with published luxA sequences from Vibrio harveyi, Vibrio fischeri and Photobacterium leiognathi. The hybridization results, sequence comparisons and the mol% G + C of the Kryptophanaron alfredi symbiont luxA gene suggest that the symbiont may be considered as a new species of luminous Vibrio related to Vibrio harveyi.

  4. Bacteriophage interactions with marine pathogenic Vibrios

    DEFF Research Database (Denmark)

    Kalatzis, Panagiotis

    development and spreading of antibiotic resistant bacteria in the environment. Bacteriophage therapy, constitutes a potent alternative not only for treatment but also for prevention of vibriosis in aquaculture and the current thesis addresses the potential and challenges of using phages to control Vibrio...... pathogens. The combinatory administration of virulent bacteriophages φSt2 and φGrn1, isolated against Vibrio alginolyticus significantly reduced the Vibrio load in cultures of Artemia salina live prey, decreasing subsequently the risk of a vibriosis outbreak in the marine hatchery. During infection...... therapy applications. Lytic phage vB_VspP_pVa5 that has been isolated against the rapidly emerging pathogen V. splendidus is also a promising candidate for phage therapy application according to its gene content and in vitro performance against its host. The genetic features of vB_VspP_pVa5 provide also...

  5. Vibrio Iron Transport: Evolutionary Adaptation to Life in Multiple Environments

    Science.gov (United States)

    Mey, Alexandra R.; Wyckoff, Elizabeth E.

    2015-01-01

    SUMMARY Iron is an essential element for Vibrio spp., but the acquisition of iron is complicated by its tendency to form insoluble ferric complexes in nature and its association with high-affinity iron-binding proteins in the host. Vibrios occupy a variety of different niches, and each of these niches presents particular challenges for acquiring sufficient iron. Vibrio species have evolved a wide array of iron transport systems that allow the bacteria to compete for this essential element in each of its habitats. These systems include the secretion and uptake of high-affinity iron-binding compounds (siderophores) as well as transport systems for iron bound to host complexes. Transporters for ferric and ferrous iron not complexed to siderophores are also common to Vibrio species. Some of the genes encoding these systems show evidence of horizontal transmission, and the ability to acquire and incorporate additional iron transport systems may have allowed Vibrio species to more rapidly adapt to new environmental niches. While too little iron prevents growth of the bacteria, too much can be lethal. The appropriate balance is maintained in vibrios through complex regulatory networks involving transcriptional repressors and activators and small RNAs (sRNAs) that act posttranscriptionally. Examination of the number and variety of iron transport systems found in Vibrio spp. offers insights into how this group of bacteria has adapted to such a wide range of habitats. PMID:26658001

  6. QStatin, a Selective Inhibitor of Quorum Sensing in Vibrio Species

    Directory of Open Access Journals (Sweden)

    Byoung Sik Kim

    2018-01-01

    Full Text Available Pathogenic Vibrio species cause diseases in diverse marine animals reared in aquaculture. Since their pathogenesis, persistence, and survival in marine environments are regulated by quorum sensing (QS, QS interference has attracted attention as a means to control these bacteria in aquatic settings. A few QS inhibitors of Vibrio species have been reported, but detailed molecular mechanisms are lacking. Here, we identified a novel, potent, and selective Vibrio QS inhibitor, named QStatin [1-(5-bromothiophene-2-sulfonyl-1H-pyrazole], which affects Vibrio harveyi LuxR homologues, the well-conserved master transcriptional regulators for QS in Vibrio species. Crystallographic and biochemical analyses showed that QStatin binds tightly to a putative ligand-binding pocket in SmcR, the LuxR homologue in V. vulnificus, and changes the flexibility of the protein, thereby altering its transcription regulatory activity. Transcriptome analysis revealed that QStatin results in SmcR dysfunction, affecting the expression of SmcR regulon required for virulence, motility/chemotaxis, and biofilm dynamics. Notably, QStatin attenuated representative QS-regulated phenotypes in various Vibrio species, including virulence against the brine shrimp (Artemia franciscana. Together, these results provide molecular insights into the mechanism of action of an effective, sustainable QS inhibitor that is less susceptible to resistance than other antimicrobial agents and useful in controlling the virulence of Vibrio species in aquacultures.

  7. Entry of Vibrio harveyi and Vibrio fischeri into the viable but nonculturable state

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, Neelam; Ravel, J.; Straube, W.L.; Hill, R.T.; Colwell, R.R.

    , direct viable counts, actively respiring cell counts, nucleoid-containing cell counts, and total counts were determined. V. harveyi incubated at 22 degrees C nutrient-limited artificial seawater (ASW) became nonculturable after approximately 62 and 45 d...

  8. QStatin, a Selective Inhibitor of Quorum Sensing in Vibrio Species.

    Science.gov (United States)

    Kim, Byoung Sik; Jang, Song Yee; Bang, Ye-Ji; Hwang, Jungwon; Koo, Youngwon; Jang, Kyung Ku; Lim, Dongyeol; Kim, Myung Hee; Choi, Sang Ho

    2018-01-30

    Pathogenic Vibrio species cause diseases in diverse marine animals reared in aquaculture. Since their pathogenesis, persistence, and survival in marine environments are regulated by quorum sensing (QS), QS interference has attracted attention as a means to control these bacteria in aquatic settings. A few QS inhibitors of Vibrio species have been reported, but detailed molecular mechanisms are lacking. Here, we identified a novel, potent, and selective Vibrio QS inhibitor, named QStatin [1-(5-bromothiophene-2-sulfonyl)-1H-pyrazole], which affects Vibrio harveyi LuxR homologues, the well-conserved master transcriptional regulators for QS in Vibrio species. Crystallographic and biochemical analyses showed that QStatin binds tightly to a putative ligand-binding pocket in SmcR, the LuxR homologue in V. vulnificus , and changes the flexibility of the protein, thereby altering its transcription regulatory activity. Transcriptome analysis revealed that QStatin results in SmcR dysfunction, affecting the expression of SmcR regulon required for virulence, motility/chemotaxis, and biofilm dynamics. Notably, QStatin attenuated representative QS-regulated phenotypes in various Vibrio species, including virulence against the brine shrimp ( Artemia franciscana ). Together, these results provide molecular insights into the mechanism of action of an effective, sustainable QS inhibitor that is less susceptible to resistance than other antimicrobial agents and useful in controlling the virulence of Vibrio species in aquacultures. IMPORTANCE Yields of aquaculture, such as penaeid shrimp hatcheries, are greatly affected by vibriosis, a disease caused by pathogenic Vibrio infections. Since bacterial cell-to-cell communication, known as quorum sensing (QS), regulates pathogenesis of Vibrio species in marine environments, QS inhibitors have attracted attention as alternatives to conventional antibiotics in aquatic settings. Here, we used target-based high-throughput screening to identify

  9. Aspects of vibrio parahaemolyticus(SAK) in fish preservation by irradiation 1. The presence of vibrio parahaemolyticus(SAK) in coastal areas of Sumatra and Java

    International Nuclear Information System (INIS)

    Suhadi, F.

    1984-01-01

    A study was carried out on the presence of vibrio parahaemolyticus in samples of sediment and seafoods originating from the eastern coast of Sumatra and the north coastal areas of Java. In a total of 2.434 samples of sediment and seafoods, 79 (3,3%) were found to contain vibrio parahaemolyticus. Among the 467 sediment samples, 1.650 fish, 133 shellfish, 123 shrimps, and 61 crab samples, 22 (4.7%), 41 (2.5%), 12 (9.0%), 2 (1,6%) and 2 (3.3%) were positive for vibrio parahaemolyticus, respectively. Based on the sampling areas, the high incidence of vibrio parahaemolyticus was found in samples collected from Riau (5.4%), while the samples from East Java was only about 0.4%. The contamination level of vibrio parahaemolyticus in samples collected from coastal areas of Sumatra and Java is relatively lower compared with the data obtained from some other coastal areas in the United States and Japan. (author)

  10. Decrease in Daphnia egg viability at elevated pH

    NARCIS (Netherlands)

    Vijverberg, J.; Kalf, D.F.; Boersma, M.

    1996-01-01

    The effect of high pH on the reproduction of two Daphnia galeata clones was experimentally investigated in the laboratory. We observed that the mortality of juveniles and adults did not increase with increasing pH in the range pH 9.0- 10.5, which agrees with what is generally reported in the

  11. Toxicidade aguda do sulfato de cobre e do triclorfon para três espécies de daphnias em presença e ausência de sedimento

    OpenAIRE

    Romero Arauco, Luis Ricardo [UNESP

    2002-01-01

    The aim of this study was to determine the acute toxicity, LE50-48h, of copper sulfate and of trichlorfon, to compare sensitivities and to evaluate the risk of environmental poisoning for three species of daphnias (Daphnia similis, Daphnia magna and Daphnia laevis), in the presence and absence of sediment. The tests for acute toxicity were performed under laboratory conditions, in a climatized room according to standardized methods with some adaptations. The LE50-48h values of copper sulfate ...

  12. Occurance and survival of Vibrio alginolyticus in Tamouda Bay (Morocco).

    Science.gov (United States)

    Sabir, M; Cohen, N; Boukhanjer, A; Ennaji, M M

    2011-10-15

    The objectives of this study were to investigate the spatial and seasonal fluctuations of Vibrio alginolyticus in marine environment of the Tamouda Bay on the Mediterranean coast of Morocco and to determine the dominant factors of the environment that govern these fluctuations. The samples (sea water, plankton, shellfish and sediment) were collected fortnightly for two years from three study sites on the coast Tamouda Bay in northern Morocco. The charge of Vibrio alginolyticus is determined by MPN method. The physicochemical parameters including temperature of sea water, pH, salinity, turbidity and chlorophyll a concentration were determined. Analysis of variance of specific variables and several principal component analyses showed that the temperature of seawater is the major determinant of seasonal distribution of Vibrio alginolyticus. The results showed a positive linear correlation between Vibrio alginolyticus and the water temperature, pH, turbidity and chlorophyll a. Similarly, there are seasonal variations and spatial of Vibrio alginolyticus in marine environment of the Tamouda bay and the highest concentrations were recorded in both years of study during the warm season whereas it was minimal during the cold season. Linear positive correlation was recorded between Vibrio alginolyticus populations in all ecological types of samples studied.

  13. A survey of oysters (Crassostrea gigas) in New Zealand for Vibrio parahaemolyticus and Vibrio vulnificus.

    Science.gov (United States)

    Kirs, M; Depaola, A; Fyfe, R; Jones, J L; Krantz, J; Van Laanen, A; Cotton, D; Castle, M

    2011-05-27

    A microbiological survey was conducted to determine the levels of total and pathogenic Vibrio parahaemolyticus (Vp) and Vibrio vulnificus (Vv) in Pacific oysters (Crassostrea gigas) collected from commercial growing areas in the North Island, New Zealand. The survey was intended to be geographically representative of commercial growing areas of Pacific oysters in New Zealand, while selecting the time frame most likely to coincide with the increased abundance of pathogenic vibrio species. Vp was detected in 94.8% of oyster samples examined (n=58) with a geometric mean concentration of 99.3 MPN/g, while Vv was detected in 17.2% of oyster samples examined with a geometric mean concentration of 7.4 MPN/g. The frequency of Vp positive samples was 1.7 fold greater than reported in a study conducted three decades ago in New Zealand. Potentially virulent (tdh positive) Vp was detected in two samples (3.4%, n=58) while no trh (another virulence marker) positive samples were detected. 16S rRNA genotype could be assigned only to 58.8% of Vv isolates (8:1:1 A:B:AB ratio, n=10). There was a good agreement [98.2% of Vp (n=280) and 94.4% of Vv (n=18) isolates] between molecular tests and cultivation based techniques used to identify Vibrio isolates and there was a significant (R(2)=0.95, Pcultivation. There was no significant correlation between any of the environmental parameters tested and Vp or Vv concentrations. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Regulation of Metalloprotease Gene Expression in Vibrio vulnificus by a Vibrio harveyi LuxR Homologue

    Science.gov (United States)

    Shao, Chung-Ping; Hor, Lien-I

    2001-01-01

    Expression of the Vibrio vulnificus metalloprotease gene, vvp, was turned up rapidly when bacterial growth reached the late log phase. A similar pattern of expression has been found in the metalloprotease gene of Vibrio cholerae, and this has been shown to be regulated by a Vibrio harveyi LuxR-like transcriptional activator. To find out whether a LuxR homologue exists in V. vulnificus, a gene library of this organism was screened by colony hybridization using a probe derived from a sequence that is conserved in various luxR-like genes of vibrios. A gene containing a 618-bp open reading frame was identified and found to be identical to the smcR gene of V. vulnificus reported previously. An isogenic SmcR-deficient (RD) mutant was further constructed by an in vivo allelic exchange technique. This mutant exhibited an extremely low level of vvp transcription compared with that of the parent strain. On the other hand, the cytolysin gene, vvhA, was expressed at a higher level in the RD mutant than in the parent strain during the log phase of growth. These data suggested that SmcR might not only be a positive regulator of the protease gene but might also be involved in negative regulation of the cytolysin gene. Virulence of the RD mutant in either normal or iron-overloaded mice challenged by intraperitoneal injection was comparable to that of the parent strain, indicating that SmcR is not required for V. vulnificus virulence in mice. PMID:11157950

  15. Vibrio lentus protects gnotobiotic sea bass (Dicentrarchus labrax L.) larvae against challenge with Vibrio harveyi.

    Science.gov (United States)

    Schaeck, M; Duchateau, L; Van den Broeck, W; Van Trappen, S; De Vos, P; Coulombet, C; Boon, N; Haesebrouck, F; Decostere, A

    2016-03-15

    Due to the mounting awareness of the risks associated with the use of antibiotics in aquaculture, treatment with probiotics has recently emerged as the preferred environmental-friendly prophylactic approach in marine larviculture. However, the presence of unknown and variable microbiota in fish larvae makes it impossible to disentangle the efficacy of treatment with probiotics. In this respect, the recent development of a germ-free culture model for European sea bass (Dicentrarchus labrax L.) larvae opened the door for more controlled studies on the use of probiotics. In the present study, 206 bacterial isolates, retrieved from sea bass larvae and adults, were screened in vitro for haemolytic activity, bile tolerance and antagonistic activity against six sea bass pathogens. Subsequently, the harmlessness and the protective effect of the putative probiotic candidates against the sea bass pathogen Vibrio harveyi were evaluated in vivo adopting the previously developed germ-free sea bass larval model. An equivalence trial clearly showed that no harmful effect on larval survival was elicited by all three selected probiotic candidates: Bacillus sp. LT3, Vibrio lentus and Vibrio proteolyticus. Survival of Vibrio harveyi challenged larvae treated with V. lentus was superior in comparison with the untreated challenged group, whereas this was not the case for the larvae supplemented with Bacillus sp. LT3 and V. proteolyticus. In this respect, our results unmistakably revealed the protective effect of V. lentus against vibriosis caused by V. harveyi in gnotobiotic sea bass larvae, rendering this study the first in its kind. Copyright © 2016. Published by Elsevier B.V.

  16. Evaluation of Daphnia magna as an indicator of Toxicity and ...

    African Journals Online (AJOL)

    Performance evaluation of wastewater treatment plants (WWTPs) with special reference to toxicity reduction using Daphnia magna straus as test organism is very important to study the likely adverse effects of the treated wastewater on the aquatic ecosystem of receiving waters and to detect common environmentally ...

  17. Daphnia fed algal food grown at elevated temperature have reduced fitness

    Directory of Open Access Journals (Sweden)

    Anna B. Sikora

    2014-05-01

    Full Text Available Lake water temperature is negatively correlated with fatty acids content and P:C ratio in green algae. Hence, elevated temperature may indirectly reduce the fitness of Daphnia due to induced decrease in algal food quality. The aim of this study was to test the hypotheses that quality of algal food decreases with increasing temperature of its culture and that large-bodied Daphnia are more vulnerable to the temperature-related deterioration of algal food quality than small-bodied ones. Laboratory life-table experiments were performed at 20°C with large-bodied D. pulicaria and small-bodied D. cucullata fed with the green alga Scenedesmus obliquus, that had been grown at temperatures of 16, 24 or 32°C. The somatic growth rates of both species decreased significantly with increasing algal culture temperature and this effect was more pronounced in D. pulicaria than in D. cucullata. In the former species, age at first reproduction significantly increased and clutch size significantly decreased with increasing temperature of algae growth, while no significant changes in these two parameters were observed in the latter species. The proportion of egg-bearing females decreased with increasing algal culture temperature in both species. The results of this study support the notion that the quality of algal food decreases with increasing water temperature and also suggest that small-bodied Daphnia species might be less vulnerable to temperature-related decreases in algal food quality than large-bodied ones.

  18. Unique and conserved genome regions in Vibrio harveyi and related species in comparison with the shrimp pathogen Vibrio harveyi CAIM 1792

    DEFF Research Database (Denmark)

    Valles, Iliana Espinoza; Vora, Gary J; Lin, Baochuan

    2015-01-01

    Vibrio harveyi CAIM 1792 is a marine bacterial strain that causes mortality in farmed shrimp in north-west Mexico, and the identification of virulence genes in this strain is important for understanding its pathogenicity. The aim of this work was to compare the V. harveyi CAIM 1792 genome....... The proteome of CAIM 1792 had higher similarity to those of other V. harveyi strains (78 %) than to those of the other closely related species Vibrio owensii (67 %), Vibrio rotiferianus (63 %) and Vibrio campbellii (59 %). Pan-genome ORFans trees showed the best fit with the accepted phylogeny based on DNA......-DNA hybridization and multi-locus sequence analysis of 11 concatenated housekeeping genes. SNP analysis clustered 34/38 genomes within their accepted species. The pangenomic and SNP trees showed that V. harveyi is the most conserved of the four species studied and V. campbellii may be divided into at least three...

  19. Aquatic toxicity of cartap and cypermethrin to different life stages of Daphnia magna and Oryzias latipes.

    Science.gov (United States)

    Kim, Younghee; Jung, Jinyong; Oh, Sorin; Choi, Kyungho

    2008-01-01

    Cartap and cypermethrin, which are among the most widely used pesticides in many countries, are considered safe because of their low mammalian toxicity and their low persistence in the environment. However, recent findings of endocrine-disrupting effects and developmental neurotoxicity have raised concerns about the potential ecological impacts of these pesticides. We evaluated the aquatic toxicity of cartap [S,S'-(2-dimethylaminotrimethylene) bis(thiocarbamate), unspecified hydrochloride] and cypermethrin [(RS)-alpha-cyano-3-phenoxybenzyl-(1RS,3RS,1RS,3SR)-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylate], both individually and combined, on different life stages of the freshwater cladoceran Daphnia magna and a freshwater teleost, Japanese medaka (Oryzias latipes). The 96-hr Daphnia median effective concentrations (EC50s) for cartap and cypermethrin were 91.0 microg/L and 0.00061 microg/L, respectively. Rapid recovery of Daphnia was observed after short-term pulsed exposure to cartap and cypermethrin; there were no adverse effects on reproduction or survival 20 d after a 24 hr exposure to cartap up to 1240 microg/L and cypermethrin up to 1.9 microg/L. Chronic continuous exposure (for 21 d) of 7-d-old Daphnia to cypermethrin significantly reduced the intrinsic population growth rate in a concentration-dependent manner. However, because the intrinsic population growth rates were all above zero, populations did not decrease even at the highest experimental concentration of 200 ng/L. Exposure of Daphnia neonates (cartap or 40 microg/L of cypermethrin. The mixture of both compounds showed no synergistic toxicity. The extremely high acute-to-chronic ratio suggests that the standard acute lethal toxicity assessment might not reflect the true environmental hazards of these frequently used pesticides. Ecological hazard assessments of long-term low dose or pulsed exposures to cartap and cypermethrin may reveal more realistic consequences of these compounds in

  20. The effect of temperature on the sensitivity of Daphnia magna to cyanobacteria is genus dependent.

    Science.gov (United States)

    Hochmuth, Jennifer D; De Schamphelaere, Karel A C

    2014-10-01

    In the present study, the authors investigated the effects of 6 different genera of cyanobacteria on multiple endpoints of Daphnia magna in a 21-d life table experiment conducted at 3 different temperatures (15 °C, 19 °C, and 23 °C). The specific aims were to test if the effect of temperature on Daphnia's sensitivity to cyanobacteria differed among different cyanobacteria and if the rank order from most to least harmful cyanobacteria to Daphnia reproduction changed or remained the same across the studied temperature range. Overall, the authors observed a decrease in harmful effects on reproduction with increasing temperature for Microcystis, Nodularia, and Aphanizomenon, and an increase in harmful effects with increasing temperature for Anabaena and Oscillatoria. No effect of temperature was observed on Daphnia sensitivity to Cylindrospermopsis. Harmful effects of Microcystis and Nodularia on reproduction appear to be mirrored by a decrease in length. On the other hand, harmful effects of Anabaena, Aphanizomenon, and Oscillatoria on reproduction were correlated with a decrease in intrinsic rate of natural increase, which was matched by a later onset of reproduction in exposures to Oscillatoria. In addition, the results suggest that the cyanobacteria rank order of harmfulness may change with temperature. Higher temperatures may increase the sensitivity of D. magna to the presence of some cyanobacteria (Anabaena and Oscillatoria) in their diet, whereas the harmful effects of others (Microcystis, Nodularia, and Aphanizomenon) may be reduced by higher temperatures. © 2014 SETAC.

  1. Temperature-dependent inhibition of opportunistic Vibrio pathogens by native coral commensal bacteria.

    Science.gov (United States)

    Frydenborg, Beck R; Krediet, Cory J; Teplitski, Max; Ritchie, Kim B

    2014-02-01

    Bacteria living within the surface mucus layer of corals compete for nutrients and space. A number of stresses affect the outcome of this competition. The interactions between native microorganisms and opportunistic pathogens largely determine the coral holobiont's overall health and fitness. In this study, we tested the hypothesis that commensal bacteria isolated from the mucus layer of a healthy elkhorn coral, Acropora palmata, are capable of inhibition of opportunistic pathogens, Vibrio shiloi AK1 and Vibrio coralliilyticus. These vibrios are known to cause disease in corals and their virulence is temperature dependent. Elevated temperature (30 °C) increased the cell numbers of one commensal and both Vibrio pathogens in monocultures. We further tested the hypothesis that elevated temperature favors pathogenic organisms by simultaneously increasing the fitness of vibrios and decreasing the fitness of commensals by measuring growth of each species within a co-culture over the course of 1 week. In competition experiments between vibrios and commensals, the proportion of Vibrio spp. increased significantly under elevated temperature. We finished by investigating several temperature-dependent mechanisms that could influence co-culture differences via changes in competitive fitness. The ability of Vibrio spp. to utilize glycoproteins found in A. palmata mucus increased or remained stable when exposed to elevated temperature, while commensals' tended to decrease utilization. In both vibrios and commensals, protease activity increased at 30 °C, while chiA expression increased under elevated temperatures for Vibrio spp. These results provide insight into potential mechanisms through which elevated temperature may select for pathogenic bacterial dominance and lead to disease or a decrease in coral fitness.

  2. Vibrio vulnificus phage PV94 is closely related to temperate phages of V. cholerae and other Vibrio species.

    Directory of Open Access Journals (Sweden)

    Mark Pryshliak

    Full Text Available BACKGROUND: Vibrio vulnificus is an important pathogen which can cause serious infections in humans. Yet, there is limited knowledge on its virulence factors and the question whether temperate phages might be involved in pathogenicity, as is the case with V. cholerae. Thus far, only two phages (SSP002 and VvAW1 infecting V. vulnificus have been genetically characterized. These phages were isolated from the environment and are not related to Vibrio cholerae phages. The lack of information on temperate V. vulnificus phages prompted us to isolate those phages from lysogenic strains and to compare them with phages of other Vibrio species. RESULTS: In this study the temperate phage PV94 was isolated from a V. vulnificus biotype 1 strain by mitomycin C induction. PV94 is a myovirus whose genome is a linear double-stranded DNA of 33,828 bp with 5'-protruding ends. Sequence analysis of PV94 revealed a modular organization of the genome. The left half of the genome comprising the immunity region and genes for the integrase, terminase and replication proteins shows similarites to V. cholerae kappa phages whereas the right half containing genes for structural proteins is closely related to a prophage residing in V. furnissii NCTC 11218. CONCLUSION: We present the first genomic sequence of a temperate phage isolated from a human V. vulnificus isolate. The sequence analysis of the PV94 genome demonstrates the wide distribution of closely related prophages in various Vibrio species. Moreover, the mosaicism of the PV94 genome indicates a high degree of horizontal genetic exchange within the genus Vibrio, by which V. vulnificus might acquire virulence-associated genes from other species.

  3. Long-term effects of ocean warming on vibrios

    Science.gov (United States)

    Pruzzo, C.; Pezzati, E.; Brettar, I.; Reid, P. C.; Colwell, R.; Höfle, M. G.; vezzulli, L.

    2012-12-01

    Vibrios are a major source of human disease, play an important role in the ecology and health of marine animals and are regarded as an abundant fraction of culturable bacteria of the ocean. There has been a considerable global effort to reduce the risk of Vibrio infections and yet in most countries both human and non-human illnesses associated with these bacteria are increasing. The cause of this increase is not known, but since vibrios are strongly thermodependant there is good reason to believe that global warming may have contributed. To investigate this possibility we examined historical samples from the Continuous Plankton Recorder (CPR) archive using advanced molecular analysis and pyrosequencing. For the first time we were able to recover environmental DNA from CPR samples that had been stored for up to ~50 years in a formalin-fixed format, which is suitable for molecular analyses of the associated prokaryotic community. To overcome the problem of DNA degradation due to the sample age and storage in formalin we develop an unbiased index of abundance for Vibrio quantification in CPR samples termed a 'relative Vibrio Abundance Index' (VAI). VAI is defined as the ratio of Vibrio spp. cells to total bacterial cells assessed by Real-Time PCR using genus-specific and universal primers, respectively, producing small amplicons of similar size (~100bp). We assessed VAI index on 55 samples (each representing 10 nautical miles tow equal to 3 m3 of filtered sewater) collected in August by the CPR survey in the North Sea from off the Rhine and Humber estuaries between 1961 to 2005 showing that the genus Vibrio has increased in prevalence in the last 44 years and that this increase is correlated significantly, during the same period, with warming sea surface temperature. In addition, by applying deep sequencing analysis of a subset of these samples we provide evidence that bacteria belonging to the genus Vibrio, including the human pathogen V. cholerae, not only increased

  4. Nutrient recovery from airplane wastewater: composition, treatment and ecotoxicological assay.

    Science.gov (United States)

    Filho, Jorge Luiz da Paixão; Tonetti, Adriano Luiz; Guimarães, Martha Tavanielli; Silva, Dailto

    2017-04-01

    For the 2014 World Cup and the 2016 Olympic Games, Brazil has expanded its airport infrastructure. This will lead to an increase in wastewater generation from aircrafts. This wastewater is traditionally taken from the aircrafts and disposed in the public sewage collection system. However, this residual water may have a different composition than the usual sanitary sewage. Therefore, it is important to study an alternative to treat this kind of wastewater. Thus, the objective of this study was to characterize and analyze the treatment of wastewater from airplane toilets through chemical precipitation for the removal of ammonia in the form of struvite. The airplanes' effluent showed a composition similar to human urine with pH 8.9, ammonia nitrogen 4,215 mg L -1 , phosphorus 430 mg L -1 and a very high acute toxicity (Vibrio fischeri). The best treatment for struvite formation was with pH 9.0 and molar ratio Mg:NH 4 :PO 4 equal to 1.5:1.0:1.0. In this case, the removal of ammonia and phosphorus achieved 97.0% and 95.3%, respectively. After this procedure, the toxicity by Vibrio fischeri decreased.

  5. Detection of Vibrio harveyi using hemolysin primer in tiger shrimp Penaeus monodon

    Directory of Open Access Journals (Sweden)

    Irma Suriyani

    2015-05-01

    Full Text Available ABSTRACT This study was aimed to analyze the sensitivity and ability of primer hemolysin in detecting pathogenetic Vibrio on tiger shrimp post-larvae (PL exposed under different exposure times in media inoculated with Vibrio harveyi. The PL of tiger shrimp were infected with 106 cfu/mL of V. harveyi by immersion method for three, six, 12, 24, 48 and 72 hours. The presence of hemolisin genes was detected by PCR techniques. The electrophoresis detected narrow hemolysin genes after PL were exposed for three and six hours. Clear visible bands of DNA Vibrio were observed for 12 hours of exposure. In contrast, no detected hemolysin gene of Vibrio was observed for PL exposed within 24, 48, and 72 hours. The rapid detection on Vibrio pathogenic for tiger shrimp PL should be conducted within three to 12 hours of exposure. No recommendation in utilizing this rapid detection for tiger shrimp PL exposed beyond 12 hours of V. harveyi. Keywords: specific primer, luminous Vibrio bacteria, pathogenic, PCR method, hemolysin gene  ABSTRAK Penelitian ini bertujuan untuk mengetahui kemampuan atau sensitivitas primer hemolisin dalam mendeteksi Vibrio patogen dengan lama pemaparan berbeda. Penelitian ini dilakukan dengan menginfeksikan Vibrio harveyi pada benur udang dengan metode perendaman pada konsentrasi 106 cfu/mL. Pengambilan sampel dilakukan pada waktu tiga, enam, 12, 24, 48, dan 72 jam pascainfeksi. Keberadaan gen hemolisin pada bakteri V. harveyi dideteksi menggunakan teknik polymerase chain reaction (PCR. Hasil elektroforesis memperlihatkan bahwa pada pemaparan tiga dan enam jam keberadaan gen hemolisin dari bakteri Vibrio patogen yang diinfeksikan sudah dapat terdeteksi pada benur walaupun masih terlihat tipis. Pada pemaparan 12 jam terlihat sangat jelas pita-pita DNA dari bakteri patogen. Sedangkan pada pemaparan 24, 48, dan 72 jam sudah tidak terdeteksi lagi gen hemolisin dari bakteri Vibrio. Hal ini diduga disebabkan terjadinya penurunan populasi

  6. Chemical and ecotoxicological characterization of ashes obtained from sewage sludge combustion in a fluidised-bed reactor.

    Science.gov (United States)

    Lapa, N; Barbosa, R; Lopes, M H; Mendes, B; Abelha, P; Boavida, D; Gulyurtlu, I; Oliveira, J Santos

    2007-08-17

    In 1999, the DEECA/INETI and the UBiA/FCT/UNL started a researching project on the partition of heavy metals during the combustion of stabilised sewage sludge (Biogran), in a fluidised-bed reactor, and on the quality of the bottom ashes and fly ashes produced. This project was entitled Bimetal and was funded by the Portuguese Foundation for Science and Technology. In this paper only the results on the combustion of Biogran are reported. The combustion process was performed in two different trials, in which different amounts of sewage sludge and time of combustion were applied. Several ash samples were collected from the bed (bottom ashes) and from two cyclones (first cyclone and second cyclone ashes). Sewage sludge, bed material (sand) and ash samples were submitted to the leaching process defined in the European leaching standard EN 12457-2. The eluates were characterized for a set of inorganic chemical species. The ecotoxicological levels of the eluates were determined for two biological indicators (Vibrio fischeri and Daphnia magna). The results were compared with the limit values of the CEMWE French Regulation. The samples were also ranked according to an index based on the chemical characterization of the eluates. It was observed an increase of the concentration of metals along the combustion system. The ashes trapped in the second cyclone, for both combustion trials, showed the highest concentration of metals in the eluates. Chemically, the ashes of the second cyclone were the most different ones. In the ecotoxicological point of view, the ecotoxicity levels of the eluates of the ashes, for both combustion cycles, did not follow the same pattern as observed for the chemical characterization. The ashes of the first cyclone showed the highest ecotoxicity levels for V. fischeri and D. magna. This difference on chemical and ecotoxicological results proves the need for performing both chemical and ecotoxicological characterizations of the sub-products of such type

  7. Chemical and ecotoxicological characterization of ashes obtained from sewage sludge combustion in a fluidised-bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lapa, N. [Environmental Biotechnology Researching Unit (UBiA), Faculty of Science and Technology (FCT), New University of Lisbon - UNL, Ed. Departamental, piso 3, gabinete 377, Quinta da Torre, 2829-516 Caparica (Portugal)]. E-mail: ncsn@fct.unl.pt; Barbosa, R. [Environmental Biotechnology Researching Unit (UBiA), Faculty of Science and Technology (FCT), New University of Lisbon - UNL, Ed. Departamental, piso 3, gabinete 377, Quinta da Torre, 2829-516 Caparica (Portugal); Lopes, M.H. [National Institute of Engineering, Technology and Innovation (INETI), Department of Energetic Engineering and Environmental Control (DEECA). Edificio J, Estrada do Paco do Lumiar, 22, 1649-038 Lisbon (Portugal); Mendes, B. [Environmental Biotechnology Researching Unit (UBiA), Faculty of Science and Technology (FCT), New University of Lisbon - UNL, Ed. Departamental, piso 3, gabinete 377, Quinta da Torre, 2829-516 Caparica (Portugal); Abelha, P. [National Institute of Engineering, Technology and Innovation (INETI), Department of Energetic Engineering and Environmental Control (DEECA). Edificio J, Estrada do Paco do Lumiar, 22, 1649-038 Lisbon (Portugal); Gulyurtlu, I. [National Institute of Engineering, Technology and Innovation (INETI), Department of Energetic Engineering and Environmental Control (DEECA). Edificio J, Estrada do Paco do Lumiar, 22, 1649-038 Lisbon (Portugal); Santos Oliveira, J. [Environmental Biotechnology Researching Unit (UBiA), Faculty of Science and Technology (FCT), New University of Lisbon - UNL, Ed. Departamental, piso 3, gabinete 377, Quinta da Torre, 2829-516 Caparica (Portugal)

    2007-08-17

    In 1999, the DEECA/INETI and the UBiA/FCT/UNL started a researching project on the partition of heavy metals during the combustion of stabilised sewage sludge (Biogran[reg]), in a fluidised-bed reactor, and on the quality of the bottom ashes and fly ashes produced. This project was entitled Bimetal and was funded by the Portuguese Foundation for Science and Technology. In this paper only the results on the combustion of Biogran[reg]) are reported. The combustion process was performed in two different trials, in which different amounts of sewage sludge and time of combustion were applied. Several ash samples were collected from the bed (bottom ashes) and from two cyclones (first cyclone and second cyclone ashes). Sewage sludge, bed material (sand) and ash samples were submitted to the leaching process defined in the European leaching standard EN 12457-2. The eluates were characterized for a set of inorganic chemical species. The ecotoxicological levels of the eluates were determined for two biological indicators (Vibrio fischeri and Daphnia magna). The results were compared with the limit values of the CEMWE French Regulation. The samples were also ranked according to an index based on the chemical characterization of the eluates. It was observed an increase of the concentration of metals along the combustion system. The ashes trapped in the second cyclone, for both combustion trials, showed the highest concentration of metals in the eluates. Chemically, the ashes of the second cyclone were the most different ones. In the ecotoxicological point of view, the ecotoxicity levels of the eluates of the ashes, for both combustion cycles, did not follow the same pattern as observed for the chemical characterization. The ashes of the first cyclone showed the highest ecotoxicity levels for V. fischeri and D. magna. This difference on chemical and ecotoxicological results proves the need for performing both chemical and ecotoxicological characterizations of the sub

  8. Chemical and ecotoxicological characterization of ashes obtained from sewage sludge combustion in a fluidised-bed reactor

    International Nuclear Information System (INIS)

    Lapa, N.; Barbosa, R.; Lopes, M.H.; Mendes, B.; Abelha, P.; Gulyurtlu, I.; Santos Oliveira, J.

    2007-01-01

    In 1999, the DEECA/INETI and the UBiA/FCT/UNL started a researching project on the partition of heavy metals during the combustion of stabilised sewage sludge (Biogran[reg]), in a fluidised-bed reactor, and on the quality of the bottom ashes and fly ashes produced. This project was entitled Bimetal and was funded by the Portuguese Foundation for Science and Technology. In this paper only the results on the combustion of Biogran[reg]) are reported. The combustion process was performed in two different trials, in which different amounts of sewage sludge and time of combustion were applied. Several ash samples were collected from the bed (bottom ashes) and from two cyclones (first cyclone and second cyclone ashes). Sewage sludge, bed material (sand) and ash samples were submitted to the leaching process defined in the European leaching standard EN 12457-2. The eluates were characterized for a set of inorganic chemical species. The ecotoxicological levels of the eluates were determined for two biological indicators (Vibrio fischeri and Daphnia magna). The results were compared with the limit values of the CEMWE French Regulation. The samples were also ranked according to an index based on the chemical characterization of the eluates. It was observed an increase of the concentration of metals along the combustion system. The ashes trapped in the second cyclone, for both combustion trials, showed the highest concentration of metals in the eluates. Chemically, the ashes of the second cyclone were the most different ones. In the ecotoxicological point of view, the ecotoxicity levels of the eluates of the ashes, for both combustion cycles, did not follow the same pattern as observed for the chemical characterization. The ashes of the first cyclone showed the highest ecotoxicity levels for V. fischeri and D. magna. This difference on chemical and ecotoxicological results proves the need for performing both chemical and ecotoxicological characterizations of the sub

  9. Dynamic Responses of Phosphorus Metabolism to Acute and Chronic Dietary Phosphorus-Limitation in Daphnia

    Directory of Open Access Journals (Sweden)

    Nicole D. Wagner

    2017-06-01

    Full Text Available Food quality is highly dynamic within lake ecosystems and varies spatially and temporally over the growing season. Consumers may need to continuously adjust their metabolism in response to this variation in dietary nutrient content. However, the rates of metabolic responses to changes in food nutrient content has received little direct study. Here, we examine responses in two metabolic phosphorus (P pools, ribonucleic acids (RNA and adenosine triphosphate (ATP, along with body mass and body P content in Daphnia magna exposed to chronic and acute dietary P-limitation. First, we examined food quality effects on animals consuming different food carbon (C:P quality over a 14 day period. Then, we raised daphnids on one food quality for 4 days, switched them to contrasting dietary treatments, and measured changes in their metabolic responses at shorter time-scales (over 48 h. Animal P, RNA, and ATP content all changed through ontogeny with adults containing relatively less of these pools with increasing body mass. Irrespective of age, Daphnia consuming high C:P diets had lower body %P, %RNA, %ATP, and mass compared to animals eating low C:P diets. Diet switching experiments revealed diet dependent changes in body %P, %RNA, %ATP, and animal mass within 48 h. We found that Daphnia switched from low to high C:P diets had some metabolic buffering capacity with decreases in body %P occurring after 24 h but mass remaining similar to initial diet conditions for 36 h after the diet switch. Switching Daphnia from low to high C:P diets caused a decrease in the RNA:P ratio after 48 h. Daphnia switched from high to low C:P diets increased their body P, RNA, and ATP content within 8–24 h. This switch from high to low C:P diets also led to increased RNA:P ratios in animal bodies. Overall, our study revealed that consumer P metabolism reflects both current and past diet due to more dynamic and rapid changes in P biochemistry than total body mass. This metabolic

  10. Zebra mussel filter feeding and food-limited production of Daphnia: Recent changes in lower trophic level dynamics of Oneida Lake, New York, U.S.A.

    Science.gov (United States)

    Horgan, M.J.; Mills, E.L.

    1999-01-01

    Exotic zebra mussels can alter lower trophic level dynamics in lakes that they colonize by consuming large quantities of phytoplankton. We simulated the indirect effects of zebra mussel grazing on Daphnia by artificially reducing phytoplankton concentration for in situ Daphnia reproduction experiments. The response of Daphnia reproduction to reduced phytoplankton was evaluated for both the in situ experiments and field observations in Oneida Lake, New York, U.S.A. Oneida Lake has had an abundant population of zebra mussels since 1992. Our experiments revealed that fecundity of individuals from two species of Daphnia was positively related to phytoplankton concentration during the spring clearwater phase, although there was no discernible effect of food concentration on fecundity in summer cyanobacteria-dominated assemblages. The experimental results suggest that Daphnia fecundity responds to chlorophyll a concentrations zebra mussels became abundant in Oneida Lake have been characterized by high water clarity, low chlorophyll concentrations, long clearwater phases, and low Daphnia biomass compared with the previous 17 years. The food web effects of zebra mussel grazing are complex and it will take more years for impacts at higher trophic levels to develop and be identified.

  11. Bioavailability and effect of pirimicarb on Daphnia magna in a laboratory freshwater/sediment system

    DEFF Research Database (Denmark)

    Kusk, K.O.

    1996-01-01

    In tests with newborn and one-week-old Daphnia magna, 48-h EC(50) values of 21-24 mu g/L and 16 mu g/L pirimicarb, respectively, were found. Older animals thus were as sensitive to pirimicarb as newborn animals. In an experiment with sediment included in the test system, all mother animals survived...... not reduced significantly during the experiment, due to the small amount of sediment used. Accumulation in the sediment was found independent of the water concentration used. This was also the case with bioaccumulation in Daphnia magna, where a bioaccumulation factor of 31-37 was found on a dry weight basis...

  12. Effects of Dry Storage and Resubmersion of Oysters on Total Vibrio vulnificus and Total and Pathogenic (tdh+/trh+) Vibrio parahaemolyticus Levels.

    Science.gov (United States)

    Kinsey, Thomas P; Lydon, Keri A; Bowers, John C; Jones, Jessica L

    2015-08-01

    Vibrio vulnificus (Vv) and Vibrio parahaemolyticus (Vp) are the two leading causes of bacterial illnesses associated with raw shellfish consumption. Levels of these pathogens in oysters can increase during routine antifouling aquaculture practices involving dry storage in ambient air conditions. After storage, common practice is to resubmerge these stored oysters to reduce elevated Vv and Vp levels, but evidence proving the effectiveness of this practice is lacking. This study examined the changes in Vv and in total and pathogenic (thermostable direct hemolysin gene and the tdh-related hemolysin gene, tdh+ and trh+) Vp levels in oysters after 5 or 24 h of dry storage (28 to 32°C), followed by resubmersion (27 to 32°C) for 14 days. For each trial, replicate oyster samples were collected at initial harvest, after dry storage, after 7 days, and after 14 days of resubmersion. Oysters not subjected to dry storage were collected and analyzed to determine natural undisturbed vibrio levels (background control). Vibrio levels were measured using a most-probable-number enrichment followed by real-time PCR. After storage, vibrio levels (excluding tdh+ and trh+ Vp during 5-h storage) increased significantly (P oysters stored for 5 h) were not significantly different (P oysters. Vv and total and pathogenic Vp levels were not significantly different (P > 0.1) from levels in background oysters after 14 days of resubmersion, regardless of dry storage time. These data demonstrate that oyster resubmersion after dry storage at elevated ambient temperatures allows vibrio levels to return to those of background control samples. These results can be used to help minimize the risk of Vv and Vp illnesses and to inform the oyster industry on the effectiveness of routine storing and resubmerging of aquaculture oysters.

  13. Vibrios and Aeromonas.

    Science.gov (United States)

    Holmberg, S D

    1988-09-01

    There are many similarities in the Vibrionaceae that cause human illness in the United States (see Table 1). Vibrios are characteristically indigenous to marine, estuarine, and brackish environments. They are distributed mainly in Gulf of Mexico coastal water, and these organisms "bloom" when the water is warm. Outbreaks of disease in humans frequently occur in summer, coinciding with multiplication of vibrios in warm water. Sporadic cases and small outbreaks of cholera continue to occur in persons living on or near the Gulf of Mexico, but infection in most persons is unrecognized. In fact, more serious and frequent illnesses result from V. vulnificus wound infections and from gastroenteritis caused by vibrios other than V. cholerae 01. Underlying hepatic or neoplastic disease (especially leukemia) apparently increases the likelihood and severity of illnesses caused by V. vulnificus and Aeromonas. Some Vibrionaceae produce clinical illness by means of enterotoxins identical or similar to cholera toxin. For many others, hemolysins, cytotoxins, and other exotoxins are necessary to produce disease; the importance of these virulence factors often is not known or the importance of these virulence factors often is not known or is of doubtful significance. Also, purported pathogenicity as demonstrated by animal models, such as fluid accumulation in ligated ileal loops, is quite nonspecific and needs to be interpreted cautiously. For Plesiomonas, a mode of pathogenesis has not been discovered. Eating raw shellfish (frequently raw oysters) has been linked epidemiologically to enteric infections with most of these bacteria; foreign travel and exposure to seawater are other frequently observed epidemiologic associations with infection. Foreign travel, particularly to the Yucatan Peninsula of Mexico, has been strongly associated with the acquisition of non-01 V. cholerae and Plesiomonas organisms. Most Vibrionaceae in the United States are susceptible in vitro--and illnesses

  14. Exopolysaccharide production by Vibrio fischeri, a fouling marine bacterium

    Digital Repository Service at National Institute of Oceanography (India)

    Rodrigues, C.L; Bhosle, N.B.

    stream_size 8 stream_content_type text/plain stream_name Biofouling_4_301.pdf.txt stream_source_info Biofouling_4_301.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  15. Two different preparation techniques for trace element determination of single Daphnia specimen using total reflection x-ray fluorescence analysis (TXRF)

    International Nuclear Information System (INIS)

    Woelfl, S.; Mages, M.

    2000-01-01

    Bio accumulation gives first information about the bio-availability of elements in waters and becomes more and more important for the characterization of the water quality. The use of common analytical techniques like ICP-MS and AAS requires large quantities of biologic sample material. Single preparation for example of Daphnia, a common species for bio-test experiments, are hardly possible with these procedures. Therefore alternatively quantitative TXRF element determination of individually prepared Daphnia was developed. Two preparation techniques for single freshwater crustacean specimen from a eutrophic branch of the river Elbe in the 'Rothehorn Park', Magdeburg (Daphnia: dry weight: 10 - 50 μg individuum -1 ) had been tested: (1) Wet preparation: the single Daphnia specimen had been washed with 0.45 μm filtered lake water and put onto quartz sample carriers. After air drying, the body length were determined in order to calculate the dry weight according to previously established body lengths-dry weight relationships. (2) Dry preparation: after collection specimen were washed with 0.45 μm filtered lake water and frozen in liquid nitrogen. The individual lyophilisated dried Daphnia were weighted using an ultrafine micro-balance and put onto quartz sample carriers. After preparation, addition of some μl Gallium standard solution and air drying the individual Daphnia were digested at the quartz sample carriers with 10 μl HNO 3 on a hot plate and dried once more. Finally the element concentrations were determined using a EXTRA IIA total-reflection x-ray fluorescence spectrometer. As a result of these investigations we can conclude that both, the 'dry' and 'wet' preparation method can be used for the element determination in small single crustaceans using TXRF spectrometry. It seems that the 'dry' method yields more precise results, but the wet method is easier to handle in field when samples cannot be fixed with liquid nitrogen. (author)

  16. Aquatic ecotoxicity effect of engineered aminoclay nanoparticles

    DEFF Research Database (Denmark)

    Choi, Moon-Hee; Hwang, Yuhoon; Uk Lee, Hyun

    2014-01-01

    the eukaryotic microalga Pseudokirchneriella subcapitata, the crustacean Daphnia magna and the bioluminescent marine bacteria Vibrio fisheri. The effective inhibitory concentration (EC50) with 95% confidence limits for the microalga was 1.29 mg/L (0.72–1.82) for the average growth rate and 0.26 mg/L (0...

  17. Assessment of mitochondrial functions in Daphnia pulex clones using high-resolution respirometry.

    Science.gov (United States)

    Kake-Guena, Sandrine A; Touisse, Kamal; Vergilino, Roland; Dufresne, France; Blier, Pierre U; Lemieux, Hélène

    2015-06-01

    The objectives of our study were to adapt a method to measure mitochondrial function in intact mitochondria from the small crustacean Daphnia pulex and to validate if this method was sensitive enough to characterize mitochondrial metabolism in clones of the pulex complex differing in ploidy levels, mitochondrial DNA haplotypes, and geographic origins. Daphnia clones belonging to the Daphnia pulex complex represent a powerful model to delineate the link between mitochondrial DNA evolution and mitochondrial phenotypes, as single genotypes with divergent mtDNA can be grown under various experimental conditions. Our study included two diploid clones from temperate environments and two triploid clones from subarctic environments. The whole animal permeabilization and measurement of respiration with high-resolution respirometry enabled the measurement of the functional capacity of specific mitochondrial complexes in four clones. When expressing the activity as ratios, our method detected significant interclonal variations. In the triploid subarctic clone from Kuujjurapik, a higher proportion of the maximal physiological oxidative phosphorylation (OXPHOS) capacity of mitochondria was supported by complex II, and a lower proportion by complex I. The triploid subarctic clone from Churchill (Manitoba) showed the lowest proportion of the maximal OXPHOS supported by complex II. Additional studies are required to determine if these differences in mitochondrial functions are related to differences in mitochondrial haplotypes or ploidy level and if they might be associated with fitness divergences and therefore selective value. © 2015 Wiley Periodicals, Inc.

  18. Chitovibrin: a chitin-binding lectin from Vibrio parahemolyticus.

    Science.gov (United States)

    Gildemeister, O S; Zhu, B C; Laine, R A

    1994-12-01

    A novel 134 kDa, calcium-independent chitin-binding lectin, 'chitovibrin', is secreted by the marine bacterium Vibrio parahemolyticus, inducible with chitin or chitin-oligomers. Chitovibrin shows no apparent enzymatic activity but exhibits a strong affinity for chitin and chito-oligomers > dp9. The protein has an isoelectric pH of 3.6, shows thermal tolerance, binds chitin with an optimum at pH 6 and is active in 0-4 M NaCl. Chitovibrin appears to be completely different from other reported Vibrio lectins and may function to bind V. parahemolyticus to chitin substrates, or to capture or sequester chito-oligomers. It may be a member of a large group of recently described proteins in Vibrios related to a complex chitinoclastic (chitinivorous) system.

  19. Visualization of ecdysteroid activity using a reporter gene in the crustacean, Daphnia.

    Science.gov (United States)

    Asada, Miki; Kato, Yasuhiko; Matsuura, Tomoaki; Watanabe, Hajime

    2014-02-01

    Ecdysone is a hormone known to play a pivotal role in crustaceans and insects. In order to evaluate the ecdysone activities in the environment and within the organism, we have developed a biomonitoring Daphnia strain by introducing a reporter gene. In this study, the ecdysone response element was inserted in the upstream region of a reporter gene, and the DNA construct was injected into Daphnia eggs. The expression of the reporter gene was detected during the early embryonic development stage. In addition, when the eggs expressing the reporter gene were exposed to ecdysone, there was enhanced expression of the reporter gene at detectable levels, while the presence of an antagonist led to its downregulation. These results suggested that this system could be potentially developed for monitoring ecdysone activities in media. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Vibrio damsela as a pathogenic agent causing mortalities in cultured sea bass (Lates calcarifer)

    OpenAIRE

    Renault, Tristan; Haffner, Philippe; Malfondet, C.; Weppe, Maurice

    1994-01-01

    Vibrio anguillarum and Vibrio ordali are species frequently described as fish pathogens. Seven species of Vibrio can also be implicated in disease problems in mariculture (Toranzo 1990). sorne of Vibrios and Barja, In addition, these marine such as V. vulnificus (Tison et al.. 1982) and V. damsela (Love et al., 1981) can also cause illness homoiothermic animals

  1. Isolation of lytic bacteriophage against Vibrio harveyi.

    Science.gov (United States)

    Crothers-Stomps, C; Høj, L; Bourne, D G; Hall, M R; Owens, L

    2010-05-01

    The isolation of lytic bacteriophage of Vibrio harveyi with potential for phage therapy of bacterial pathogens of phyllosoma larvae from the tropical rock lobster Panulirus ornatus. Water samples from discharge channels and grow-out ponds of a prawn farm in northeastern Australia were enriched for 24 h in a broth containing four V. harveyi strains. The bacteriophage-enriched filtrates were spotted onto bacterial lawns demonstrating that the bacteriophage host range for the samples included strains of V. harveyi, Vibrio campbellii, Vibrio rotiferianus, Vibrio parahaemolyticus and Vibrio proteolyticus. Bacteriophage were isolated from eight enriched samples through triple plaque purification. The host range of purified phage included V. harveyi, V. campbellii, V. rotiferianus and V. parahaemolyticus. Transmission electron microscope examination revealed that six purified phage belonged to the family Siphoviridae, whilst two belonged to the family Myoviridae. The Myoviridae appeared to induce bacteriocin production in a limited number of host bacterial strains, suggesting that they were lysogenic rather than lytic. A purified Siphoviridae phage could delay the entry of a broth culture of V. harveyi strain 12 into exponential growth, but could not prevent the overall growth of the bacterial strain. Bacteriophage with lytic activity against V. harveyi were isolated from prawn farm samples. Purified phage of the family Siphoviridae had a clear lytic ability and no apparent transducing properties, indicating they are appropriate for phage therapy. Phage resistance is potentially a major constraint to the use of phage therapy in aquaculture as bacteria are not completely eliminated. Phage therapy is emerging as a potential antibacterial agent that can be used to control pathogenic bacteria in aquaculture systems. The development of phage therapy for aquaculture requires initial isolation and determination of the bacteriophage host range, with subsequent creation of

  2. Effects of the cyanobacterial neurotoxin B-N-methylamino-L-alamine (BMAA) on the survival, mobility and reproduction of Daphnia magna

    NARCIS (Netherlands)

    Lürling, M.F.L.L.W.; Faassen, E.J.; Eenennaam, van J.S.

    2011-01-01

    In short-term tests and chronic life table assays, Daphnia magna was exposed to the cyanobacterial neurotoxic non-protein amino acid ß-N-methylamino-l-alanine (BMAA). BMAA was not acutely lethal to Daphnia (LC50–48h > 10 000 µg L-1), but reduced mobility (IC50–48h 40 µg L-1) and affected life

  3. Infection Vibrio sp. Bacteria on Kappaphycus Seaweed Varieties Brown and Green

    Science.gov (United States)

    Irmawati, Yuni; Sudirjo, Fien

    2017-10-01

    Disease in seaweed or ice-ice, until today is still a major problem in the cultivation of seaweed. Changes in extreme environmental conditions is a trigger factor of ice-ice, which can result in seaweed susceptible to infection with pathogenic microorganisms, such as bacteria Vibrio sp. This research aims to determine the bacteria Vibrio sp. infection in seaweed Kappaphycus varieties of brown and green. Vibrio sp. bacteria isolated in the infected seaweed thallus ice-ice, grown on TCBS media, purification, gram staining and biochemical tests. Vibrio sp. infected to seaweed Kappaphycus brown and green varieties in containers controlled by different density, 105 CFU/ml, 106 CFU/ml and 107CFU/ml. Observations were made to change clinical effect in thallus seaweed for 14 days of observation. The results obtained show that the levels of infection bacteria Vibrio sp. higher in seaweed Kappaphycus green varieties both in density 105 CFU/ml, 106 CFU/ml and 107CFU/ml, when compared with varieties brown.

  4. MR findings of infectious myositis caused by vibrio vulnificus: case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon Ho; Na, Jae Boem [Gyeongsang National University College of Medicine, Jinju (Korea, Republic of)

    2003-03-01

    Vibrio vulnificus infection is a fatal disease occurring after the consumption of seafood in patients with underlying liver disease. Inflammation of the skin, subcutanous fat and fascia disseminates from the lower extremity to the trunk and upper extremity. Infection myositis caused by vibrio vulnificus is rare, and its MR findings have not been reported. We report these in a case of infectious myositis caused by vibrio vulnificus involving both lower extremities.

  5. MR findings of infectious myositis caused by vibrio vulnificus: case report

    International Nuclear Information System (INIS)

    Lee, Joon Ho; Na, Jae Boem

    2003-01-01

    Vibrio vulnificus infection is a fatal disease occurring after the consumption of seafood in patients with underlying liver disease. Inflammation of the skin, subcutanous fat and fascia disseminates from the lower extremity to the trunk and upper extremity. Infection myositis caused by vibrio vulnificus is rare, and its MR findings have not been reported. We report these in a case of infectious myositis caused by vibrio vulnificus involving both lower extremities

  6. Sequential assessment via daphnia and zebrafish for systematic toxicity screening of heterogeneous substances.

    Science.gov (United States)

    Jang, Gun Hyuk; Park, Chang-Beom; Kang, Benedict J; Kim, Young Jun; Lee, Kwan Hyi

    2016-09-01

    Environment and organisms are persistently exposed by a mixture of various substances. However, the current evaluation method is mostly based on an individual substance's toxicity. A systematic toxicity evaluation of heterogeneous substances needs to be established. To demonstrate toxicity assessment of mixture, we chose a group of three typical ingredients in cosmetic sunscreen products that frequently enters ecosystems: benzophenone-3 (BP-3), ethylhexyl methoxycinnamate (EHMC), and titanium dioxide nanoparticle (TiO2 NP). We first determined a range of nominal toxic concentration of each ingredient or substance using Daphnia magna, and then for the subsequent organismal level phenotypic assessment, chose the wild-type zebrafish embryos. Any phenotype change, such as body deformation, led to further examinations on the specific organs of transgenic zebrafish embryos. Based on the systematic toxicity assessments of the heterogeneous substances, we offer a sequential environmental toxicity assessment protocol that starts off by utilizing Daphnia magna to determine a nominal concentration range of each substance and finishes by utilizing the zebrafish embryos to detect defects on the embryos caused by the heterogeneous substances. The protocol showed additive toxic effects of the mixtures. We propose a sequential environmental toxicity assessment protocol for the systematic toxicity screening of heterogeneous substances from Daphnia magna to zebrafish embryo in-vivo models. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Vibrio ecology - Identifying Environmental Determinants Favorable for the Presence and Transmission of Pathogenic Vibrios

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In a tri-coastal collaborative study, the population densities of vibrios are being determined in the Mississippi Sound, Puget Sound, Chesapeake Bay, and Timbalier...

  8. Abundance and antibiotic susceptibility of Vibrio spp. isolated from microplastics

    Science.gov (United States)

    Laverty, A. L.; Darr, K.; Dobbs, F. C.

    2016-02-01

    In recent years, there has been a growing concern for `microplastics' (particles pieces, paired seawater samples, and from them cultured 44 putative Vibrio spp. isolates, 18 of which were PCR-confirmed as V. parahaemolyticus and 3 as V. vulnificus. There were no PCR-confirmed V. cholerae isolates. We used the Kirby-Bauer disk diffusion susceptibility test to examine the isolates' response to six antibiotics: chloramphenicol (30μg), gentamicin (10μg), ampicillin (10μg), streptomycin (10μg), tetracycline (30μg), and rifampin (5μg). Vibrio isolates were susceptible to three or more of the six antibiotics tested and all were susceptible to tetracycline and chloramphenicol. There were no apparent differences between the antibiotic susceptibilities of vibrios isolated from microplastics compared to those from the water column. In every instance tested, vibrios on microplastics were enriched by at least two orders of magnitude compared to those from paired seawater samples. This study demonstrates that microplastic particles serve as a habitat for Vibrio species, in particular V. vulnificus and V. parahaemolyticus, confirming the conjecture of Zettler et al. (2013) that plastics may serve as a vector for these and other potentially pathogenic bacteria.

  9. Antibiotic Resistant Salmonella and Vibrio Associated with Farmed Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Sanjoy Banerjee

    2012-01-01

    Full Text Available Salmonella and Vibrio species were isolated and identified from Litopenaeus vannamei cultured in shrimp farms. Shrimp samples showed occurrence of 3.3% of Salmonella and 48.3% of Vibrio. The isolates were also screened for antibiotic resistance to oxolinic acid, sulphonamides, tetracycline, sulfamethoxazole/trimethoprim, norfloxacin, ampicillin, doxycycline hydrochloride, erythromycin, chloramphenicol, and nitrofurantoin. Salmonella enterica serovar Corvallis isolated from shrimp showed individual and multiple antibiotic resistance patterns. Five Vibrio species having individual and multiple antibiotic resistance were also identified. They were Vibrio cholerae (18.3%, V. mimicus (16.7%, V. parahaemolyticus (10%, V. vulnificus (6.7%, and V. alginolyticus (1.7%. Farm owners should be concerned about the presence of these pathogenic bacteria which also contributes to human health risk and should adopt best management practices for responsible aquaculture to ensure the quality of shrimp.

  10. Paracetamol degradation intermediates and toxicity during photo-Fenton treatment using different iron species.

    Science.gov (United States)

    Trovó, Alam G; Pupo Nogueira, Raquel F; Agüera, Ana; Fernandez-Alba, Amadeo R; Malato, Sixto

    2012-10-15

    The photo-Fenton degradation of paracetamol (PCT) was evaluated using FeSO(4) and the iron complex potassium ferrioxalate (FeOx) as iron source under simulated solar light. The efficiency of the degradation process was evaluated considering the decay of PCT and total organic carbon concentration and the generation of carboxylic acids, ammonium and nitrate, expressed as total nitrogen. The results showed that the degradation was favored in the presence of FeSO(4) in relation to FeOx. The higher concentration of hydroxylated intermediates generated in the presence of FeSO(4) in relation to FeOx probably enhanced the reduction of Fe(III) to Fe(II) improving the degradation efficiency. The degradation products were determined using liquid chromatography electrospray time-of-flight mass spectrometry. Although at different concentrations, the same intermediates were generated using either FeSO(4) or FeOx, which were mainly products of hydroxylation reactions and acetamide. The toxicity of the sample for Vibrio fischeri and Daphnia magna decreased from 100% to less than 40% during photo-Fenton treatment in the presence of both iron species, except for D. magna in the presence of FeOx due to the toxicity of oxalate to this organism. The considerable decrease of the sample toxicity during photo-Fenton treatment using FeSO(4) indicates a safe application of the process for the removal of this pharmaceutical. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. A contribution towards the risk assessment of soils from the São Domingos Mine (Portugal): Chemical, microbial and ecotoxicological indicators

    International Nuclear Information System (INIS)

    Alvarenga, Paula; Palma, Patrícia; Varennes, Amarilis de; Cunha-Queda, Ana C.

    2012-01-01

    This study is a contribution towards a risk assessment of the São Domingos Mine area (Portugal), integrating information from: soil physicochemical characteristics, pseudo-total and bioavailable trace elements (As, Cd, Cr, Cu, Ni, Pb and Zn), ecotoxicological evaluation, and microbial indicators. The bioassays using soil eluates (seed germination, luminescent inhibition of Vibrio fischeri and Daphnia magna immobilization) confirmed the soil toxicity categorization obtained with the bioassays using soil (plant growth tests, Eisenia fetida mortality and avoidance behaviour). However, the soil identified as the most toxic using bioassays, was different from the expected when considering the results from pseudo-total and effective bioavailable trace elements. Taking in consideration the observations, it is highly recommended to complement the results from environmental chemistry with results from bioassays, in order to provide a more complete and relevant information on the bioavailability of contaminants and to characterize the risk of contaminated soils. - Highlights: ► Impaired soil retention and habitat functions for all tested soils. ► Aquatic and terrestrial bioassays agreed in the soil toxicity categorization. ► Do results obtained by chemical methods really translate into “biological availability”? ► In multi-contaminated sites, risk estimation based only on chemical methods is inadequate. ► Bioassays provide a more realistic risk assessment of contaminated sites. - Bioassays provide a more complete and relevant information to characterize the risk of contaminated soils, and should be used to complement chemical results.

  12. Impacts of discarded coffee waste on human and environmental health.

    Science.gov (United States)

    Fernandes, A S; Mello, F V C; Thode Filho, S; Carpes, R M; Honório, J G; Marques, M R C; Felzenszwalb, I; Ferraz, E R A

    2017-07-01

    Coffee is one of the most widely consumed beverages throughout the world. So far, many studies have shown the properties of coffee beverages, but little is known about its impacts on human and environmental health from its discard in the environment. So, the present work aims to investigate the mutagenic, genotoxic, cytotoxic and ecotoxic effects of leached (LE) and solubilized (SE) extracts from coffee waste, simulating the disposal of this residue in landfills and via sewage systems, respectively. Chemical analyses were also carried out. LE and SE induced mutagenicity in the TA98 Salmonella strain with and without exogenous metabolization (S9). In the TA100 only SE induced mutagenicity, what was observed without S9. An increase in the frequency of micronuclei was observed in HepG2 cell line after 3 and 24h of exposure to both extracts. No cytotoxic effects were observed in HepG2 cells by WST-1 assay. The EC50 values for the LE and SE were 1.5% and 11.26% for Daphnia similis, 0.12% and 1.39% for Ceriodaphnia dubia and 6.0% and 5.5% for Vibrio fischeri, respectively. Caffeine and several transition metals were found in both extracts. Coffee waste discarded in the environment may pose a risk to human and environmental health, since this compound can cause DNA damage and present toxicity to aquatic organisms. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Daphnia magna fitness during low food supply under different water temperature and brownification scenarios

    Directory of Open Access Journals (Sweden)

    Andrea Gall

    2016-11-01

    Full Text Available Much of our current knowledge about non-limiting dietary carbon supply for herbivorous zooplankton is based on experimental evidence and typically conducted at ~1 mg C L-1 and ~20°C. Here we ask how low supply of dietary carbon affects somatic growth, reproduction, and survival of Daphnia magna and test effects of higher water temperature (+3 °C relative to ambient and brownification (3X higher than natural water color; both predicted effects of climate change during fall cooling. We predicted that even at very low carbon supply (~5µg C L-1, higher water temperature and brownification will allow D. magna to increase its fitness. Neonates (<24 h old were incubated with lake seston for 4 weeks (October-November 2013 in experimental bottles submerged in outdoor mesocosms to explore effects of warmer and darker water. Higher temperature and brownification did not significantly affect food quality, as assessed by its fatty acid composition. Daphnia exposed to both increased temperature and brownification had highest somatic growth and were the only that reproduced, and higher temperature caused the highest Daphnia survival success. These results suggest that even under low temperature and thus lower physiological activity, low food quantity is more important than its quality for D. magna fitness.

  14. Ecology of Vibrio vulnificus in estuarine waters of eastern North Carolina.

    Science.gov (United States)

    Pfeffer, Courtney S; Hite, M Frances; Oliver, James D

    2003-06-01

    While several studies on the ecology of Vibrio vulnificus in Gulf Coast environments have been reported, there is little information on the distribution of this pathogen in East Coast waters. Thus, we conducted a multiyear study on the ecology of V. vulnificus in estuarine waters of the eastern United States, employing extensive multiple regression analyses to reveal the major environmental factors controlling the presence of this pathogen, and of Vibrio spp., in these environments. Monthly field samplings were conducted between July 2000 and April 2002 at six different estuarine sites along the eastern coast of North Carolina. At each site, water samples were taken and nine physicochemical parameters were measured. V. vulnificus isolates, along with estuarine bacteria, Vibrio spp., Escherichia coli organisms, and total coliforms, were enumerated in samples from each site by using selective media. During the last 6 months of the study, sediment samples were also analyzed for the presence of vibrios, including V. vulnificus. Isolates were confirmed as V. vulnificus by using hemolysin gene PCR or colony hybridization. V. vulnificus was isolated only when water temperatures were between 15 and 27 degrees C, and its presence correlated with water temperature and dissolved oxygen and vibrio levels. Levels of V. vulnificus in sediments were low, and no evidence for an overwintering in this environment was found. Multiple regression analysis indicated that vibrio levels were controlled primarily by temperature, turbidity, and levels of dissolved oxygen, estuarine bacteria, and coliforms. Water temperature accounted for most of the variability in the concentrations of both V. vulnificus (47%) and Vibrio spp. (48%).

  15. Vibrio chromosome-specific families

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David

    2014-01-01

    We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished...... chromosomes, we find a core set of 1269 encoded protein families for chromosome 1, and a core of 252 encoded protein families for chromosome 2. Many of these core proteins are also found in the draft genomes (although which chromosome they are located on is unknown.) Of the chromosome specific core protein...... families, 1169 and 153 are uniquely found in chromosomes 1 and 2, respectively. Gene ontology (GO) terms for each of the protein families were determined, and the different sets for each chromosome were compared. A total of 363 different "Molecular Function" GO categories were found for chromosome 1...

  16. Vibrio Parahemolyticus in the Wastewater of Kermanshah City

    Directory of Open Access Journals (Sweden)

    Ali Almasi

    2005-11-01

    Full Text Available آب و فاضلاب                                                                                                                                                                                                               شماره 51- سال 1383     Municipal wastewater is one of the most important pollution sources for water supply resources. Soil, vegetable, and food material are exposed as well. Identification and enumeration of pathogenic agents particularly pathogenic Vibrios are beneficial for control and prevention planning of the infectious diseases. This research carried out to identify the distribution of the recognized pathogenic Vibrios emphasizing on identification of Vibrio cholerain the wastewater of city of Kermanshah in 2001. Population of city of Kermanshah was estimated over 713000 and produced wastewater was approximately 150 l/cap/d. The method of study was cross-sectional descriptive. Sampling procedure was adopted from standard Methods for the Examination of water and wastewater, and the method for Vibrios identification was according to finegold 1990. There were 8 discharge outlet domestic wastewaters, which had been chosen as sampling sites. Samples were collected weekly in randomized manner in day time. Although 288 samples should be collected statistically, 339 samples were collected and analyzed. The results indicated that site 7 with 5 positives, sites 4 and 8 with 3 positives, site 5 with 2 postitives and sites 2, 3 and 6 with one positive suspected to vibrio pathogens. However, not any Vibrio detected in site 1. The most positive samples were seen in spring, late summer and early autumn. The positive results were detected in May, June, September, and October. Among samples which have been detected as a

  17. A Model Compound Study: The ecotoxicological evaluation of five organic contaminants with a battery of marine bioassays

    OpenAIRE

    Macken, A.; Giltrap, M.; Foley, B.; McGovern, E.; McHugh, B.; Davoren, M.

    2008-01-01

    This paper describes the ecotoxicological evaluation of five organic contaminants frequently detected in marine sediments (tributyltin, triphenyltin, benzo[a]pyrene, fluoranthene, and PCB 153) using three marine species (Vibrio fischeri, Tetraselmis suecica, and Tisbe battagliai). The sensitivity of each species varied for all compounds. The triorganotins were consistently the most toxic to all species. The applicability of each test system to assess the acute toxicity of environmental contam...

  18. Phenology of Daphnia in a Northern Italy pond during the weather anomalous 2014

    Czech Academy of Sciences Publication Activity Database

    Rossi, V.; Maurone, C.; Benassi, G.; Marková, Silvia; Kotlík, Petr; Bellin, N.; Ferrari, I.

    2015-01-01

    Roč. 74, č. 3 (2015), s. 631-638 ISSN 1129-5767 Institutional support: RVO:67985904 Keywords : interannual meteo-climatic variability * Daphnia pulex * D. longispina Subject RIV: EG - Zoology Impact factor: 1.725, year: 2015

  19. Septicemia caused by Vibrio parahemolyticus: a case report.

    Science.gov (United States)

    Hsu, G J; Young, T; Peng, M Y; Chang, F Y; Chou, M Y

    1993-11-01

    Vibrio parahemolyticus is a halophilic marine vibrio commonly associated with outbreaks of acute gastroenteritis which also sometimes causes serious wound infection. It is an uncommon cause of septicemia. A few reports suggest that patients with chronic liver disease and leukemia are more susceptible. A case of liver cirrhosis with septicemia caused by this organism is discussed. The patient's condition rapidly deteriorated, and he died 12 hours after admission.

  20. Recovery and evolutionary analysis of complete integron gene cassette arrays from Vibrio

    Directory of Open Access Journals (Sweden)

    Gillings Michael R

    2006-01-01

    Full Text Available Abstract Background Integrons are genetic elements capable of the acquisition, rearrangement and expression of genes contained in gene cassettes. Gene cassettes generally consist of a promoterless gene associated with a recombination site known as a 59-base element (59-be. Multiple insertion events can lead to the assembly of large integron-associated cassette arrays. The most striking examples are found in Vibrio, where such cassette arrays are widespread and can range from 30 kb to 150 kb. Besides those found in completely sequenced genomes, no such array has yet been recovered in its entirety. We describe an approach to systematically isolate, sequence and annotate large integron gene cassette arrays from bacterial strains. Results The complete Vibrio sp. DAT722 integron cassette array was determined through the streamlined approach described here. To place it in an evolutionary context, we compare the DAT722 array to known vibrio arrays and performed phylogenetic analyses for all of its components (integrase, 59-be sites, gene cassette encoded genes. It differs extensively in terms of genomic context as well as gene cassette content and organization. The phylogenetic tree of the 59-be sites collectively found in the Vibrio gene cassette pool suggests frequent transfer of cassettes within and between Vibrio species, with slower transfer rates between more phylogenetically distant relatives. We also identify multiple cases where non-integron chromosomal genes seem to have been assembled into gene cassettes and others where cassettes have been inserted into chromosomal locations outside integrons. Conclusion Our systematic approach greatly facilitates the isolation and annotation of large integrons gene cassette arrays. Comparative analysis of the Vibrio sp. DAT722 integron obtained through this approach to those found in other vibrios confirms the role of this genetic element in promoting lateral gene transfer and suggests a high rate of gene

  1. Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment and cultured oysters in the Chesapeake Bay, Maryland, USA

    Directory of Open Access Journals (Sweden)

    Kristi S Shaw

    2014-05-01

    Full Text Available To determine if a storm event (i.e., high winds, large volumes of precipitation could alter concentrations of Vibrio vulnificus and Vibrio parahaemolyticus in aquacultured oysters (Crassostrea virginica and associated surface water and sediment, this study followed a sampling timeline before and after Hurricane Irene impacted the Chesapeake Bay estuary in late August 2011. Aquacultured oysters were sampled from two levels in the water column: surface 0.3 m and near-bottom just above the sediment. Concentrations of each Vibrio spp. and associated virulence genes were measured in oysters with a combination of real-time PCR and most probable number enrichment methods, and in sediment and surface water with real-time PCR. While concentration shifts of each Vibrio species were apparent post-storm, statistical tests indicated no significant change in concentration change for either Vibrio species by location (surface or near bottom oysters or date sampled (oyster tissue, surface water and sediment concentrations. V. vulnificus in oyster tissue was correlated with total suspended solids (r=0.41, p=0.04, and V. vulnificus in sediment was correlated with secchi depth (r=-0.93, p< 0.01, salinity (r=-0.46, p=0.02, tidal height (r=-0.45, p=0.03, and surface water V. vulnificus (r=0.98, p< 0.01. V. parahaemolyticus in oyster tissue did not correlate with environmental measurements, but V. parahaemolyticus in sediment and surface water correlated with several measurements including secchi depth (r=-0.48, p=0.02[sediment]; r=-0.97 p< 0.01[surface water] and tidal height (r=-0.96. p< 0.01[sediment], r=-0.59,p< 0.01 [surface water]. The concentrations of Vibrio spp. were higher in oysters relative to other studies (average V. vulnificus 4x105 MPN g-1, V. parahaemolyticus 1x105 MPN g-1, and virulence-associated genes were detected in most oyster samples. This study provides a first estimate of storm-related Vibrio density changes in oyster tissues, sediment and

  2. Potensi Ekstrak Daun Binahong (Anredera cordifolia Sebagai Penghambat Bakteri Vibrio harveyi

    Directory of Open Access Journals (Sweden)

    Gde Raka Angga Kartika

    2016-07-01

    Full Text Available Binahong (Anredera cordifolia is a plant that can treat various kinds of diseases, because this plant has a high antioxidant content and as an antibacterial and antiviral. Vibriosis disease caused by the bacterium Vibrio harveyi is a serious problem in marine and brackish culture, this disease can cause death for shrimp and fish that farmed in marine or brackish. This study aims to determine the potential of using leaf extract Binahong with different concentrations as Vibrio harveyi inhibiting bacterial growth in vitro. The method used is to test the Minimum inhibitory concentration (MIC to determine minimum levels inhibit the growth of Vibrio harveyi and Minimum Bactericidal Concentration (MBC using paper disc. The results showed the use of leaf extract Binahong (Anredera cordifolia with different concentrations significant effect on the growth of Vibrio harveyi in vitro. Binahong leaf extract (Anredera cordifolia with a concentration of 3%, 5%, 7%, 9%, 11% and 13% is only bacteriostatic which inhibits the growth of bacteria Vibrio harveyi with the best concentration obtained is equal to 13%.

  3. Vibrio population structure - Genetic and population structure analysis of clinical and environmental Vibrio parahaemolyticus strains

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Vibrio parahaemolyticus (Vp) is a marine bacterium capable of causing severe gastroenteritis in humans, usually through the consumption of raw shellfish. Before...

  4. Vibrio rotiferianus sp. nov., isolated from cultures of the rotifer Brachionus plicatilis.

    Science.gov (United States)

    Gomez-Gil, B; Thompson, F L; Thompson, C C; Swings, J

    2003-01-01

    Five Gram-negative bacterial strains, oxidase-positive, motile by means of more than one polar flagella, facultative anaerobe, arginine dihydrolase-negative, lysine- and omithine decarboxylase-positive, sensitive to the vibriostatic agent O/129, were isolated from a flow-through rotifer culture system in Gent, Belgium, and previously characterized by fluorescent amplified fragment length polymorphism. Comparison of the 16S rDNA sequence of strain LMG 21460T indicated close relationships (approximately 99% similarity) to Vibrio campbellii, Vibrio harveyi, Vibrio alginolyticus and Vibrio parahaemolyticus. However, DNA hybridization experiments revealed similarity values below 70% with its closest species V. campbellii and V. harveyi. Additionally, the analysed strains differ from related Vibrio species by the utilization of melibiose and production of acid from L-arabinose and amygdalin. Among the strains analysed, differences were observed in some phenotypic characters, particularly susceptibility to ampicillin, polymyxin B and amikacin, and urease activity. The major fatty acids identified were 16:0, 18:1 omega7c, 14:0, 12:0 3-OH and 18:0. Vibrio rotiferianus sp. nov. is proposed, with type strain LMG 21460T (=CAIM 577T); it has a DNA G+C content of 44.5 +/- 0.01 mol%.

  5. Hemolytic and urease activities in vibrios isolated from fresh and frozen oysters

    Directory of Open Access Journals (Sweden)

    Renata Albuquerque Costa

    2013-01-01

    Full Text Available INTRODUCTION: The present study aimed to survey the Vibrio microbiota of oysters (Crassostrea rhizophorae obtained from restaurants in Fortaleza, State of Ceará, Brazil, and to identify virulence factors. METHODS: The isolated vibrios were submitted to biochemical identification and were tested for hemolytic and urease activities. RESULTS: The isolated strains belonged to 13 species, with predominance of Vibrio mimicus. Of the strain isolates only from fresh samples, 20.5% and 2.8% showed hemolytic and urease activities, respectively. CONCLUSIONS: The findings support the little-publicized claim that Vibrio species other than V. parahaemolyticus and V. vulnificus can represent a health risk to public health.

  6. Oral administration of formalin killed Vibrio anguillarum cells improves growth and protection against challenge with Vibrio harveyi in banana shrimp.

    Science.gov (United States)

    Patil, P K; Gopal, C; Panigrahi, A; Rajababu, D; Pillai, S M

    2014-03-01

    Larval rearing in hatcheries and highly intensive grow-out culture practices followed in shrimp production systems favour the growth of potential pathogenic bacterial loads. This study reports the efficacy of formalin-killed vibrio bacterin on growth, survival and protection to challenge with virulent Vibrio harveyi and Vibrio anguillarum in juveniles of banana shrimp Fenneropenaeus merguiensis. Postlarvae 15 (0·24 ± 0·01 g) were administered orally in different concentrations of bacterial preparation (0, 10(6) , 10(8) , 10(10) and 10(12 ) CFU kg(-1) feed) for a period of 6 weeks. Physicochemical and microbial quality of water in larval rearing tanks, and growth and survival of the postlarvae were monitored at regular intervals, and body composition was estimated at the end of the experiment. Shrimps were challenged with V. harveyi and V. anguillarum, and cumulative mortality was calculated. The group receiving 10(8)  CFU kg(-1) feed showed highest average weight gain (162·66 ± 22·94 mg) and survival (90·33 ± 4·5%) and lowest cumulative mortality following the challenge with V. anguillarum (26%) and V. harveyi (36·67%). The results of the study suggest that formalized vibrio administered orally to F. merguiensis postlarvae could induce both homologous and heterologous protection against V. anguillarum and V. harveyi. 'Vaccination' of shrimp postlarvae at hatcheries would help in preventing the losses due to vibriosis and the most susceptible stages of shrimp development. The study demonstrates the cross-protection offered by the oral feeding of formalin-killed Vibrio anguillarum against pathogenic V. harveyi challenge at the early developmental stages of banana shrimp, Fenneropenaeus merguiensis. © 2013 The Society for Applied Microbiology.

  7. The long-term effects of acute exposure to ionising radiation on survival and fertility in Daphnia magna

    International Nuclear Information System (INIS)

    Sarapultseva, Elena I.; Dubrova, Yuri E.

    2016-01-01

    The results of recent studies have provided strong evidence for the transgenerational effects of parental exposure to ionising radiation and chemical mutagens. However, the transgenerational effects of parental exposure on survival and fertility remain poorly understood. To establish whether parental irradiation can affect the survival and fertility of directly exposed organisms and their offspring, crustacean Daphnia magna were given 10, 100, 1000 and 10,000 mGy of acute γ-rays. Exposure to 1000 and 10,000 mGy significantly compromised the viability of irradiated Daphnia and their first-generation progeny, but did not affect the second-generation progeny. The fertility of F 0 and F 1 Daphnia gradually declined with the dose of parental exposure and significantly decreased at dose of 100 mGy and at higher doses. The effects of parental irradiation on the number of broods were only observed among the F 0 Daphnia exposed to 1000 and 10,000 mGy, whereas the brood size was equally affected in the two consecutive generations. In contrast, the F 2 total fertility was compromised only among progeny of parents that received the highest dose of 10,000 mGy. We propose that the decreased fertility observed among the F 2 progeny of parents exposed to 10,000 mGy is attributed to transgenerational effects of parental irradiation. Our results also indicate a substantial recovery of the F 2 progeny of irradiated F 0 Daphnia exposed to the lower doses of acute γ-rays. - Highlights: • Viability of irradiated daphnids and their F 1 progeny is compromised. • Viability of the F 2 progeny of irradiated parents is not affected. • Total fertility of irradiated daphnids and their F 1 progeny declines with the dose. • Total fertility of the F 2 progeny of parents exposed to 10,000 mGy is compromised. • The decreased fertility among the F 2 progeny is transgenerational phenomenon.

  8. The long-term effects of acute exposure to ionising radiation on survival and fertility in Daphnia magna

    Energy Technology Data Exchange (ETDEWEB)

    Sarapultseva, Elena I. [Department of Biology, Institute of Nuclear Power Engineering NRNU MEPhI, Studgorodok,1, Obninsk, Kaluga Region 249040 (Russian Federation); National Research Nuclear University “MEPhI”, Kashirskoe Highway, 31, Moscow 115409 (Russian Federation); Dubrova, Yuri E., E-mail: yed2@le.ac.uk [Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina Str. 3, 11933 Moscow (Russian Federation)

    2016-10-15

    The results of recent studies have provided strong evidence for the transgenerational effects of parental exposure to ionising radiation and chemical mutagens. However, the transgenerational effects of parental exposure on survival and fertility remain poorly understood. To establish whether parental irradiation can affect the survival and fertility of directly exposed organisms and their offspring, crustacean Daphnia magna were given 10, 100, 1000 and 10,000 mGy of acute γ-rays. Exposure to 1000 and 10,000 mGy significantly compromised the viability of irradiated Daphnia and their first-generation progeny, but did not affect the second-generation progeny. The fertility of F{sub 0} and F{sub 1}Daphnia gradually declined with the dose of parental exposure and significantly decreased at dose of 100 mGy and at higher doses. The effects of parental irradiation on the number of broods were only observed among the F{sub 0}Daphnia exposed to 1000 and 10,000 mGy, whereas the brood size was equally affected in the two consecutive generations. In contrast, the F{sub 2} total fertility was compromised only among progeny of parents that received the highest dose of 10,000 mGy. We propose that the decreased fertility observed among the F{sub 2} progeny of parents exposed to 10,000 mGy is attributed to transgenerational effects of parental irradiation. Our results also indicate a substantial recovery of the F{sub 2} progeny of irradiated F{sub 0}Daphnia exposed to the lower doses of acute γ-rays. - Highlights: • Viability of irradiated daphnids and their F{sub 1} progeny is compromised. • Viability of the F{sub 2} progeny of irradiated parents is not affected. • Total fertility of irradiated daphnids and their F{sub 1} progeny declines with the dose. • Total fertility of the F{sub 2} progeny of parents exposed to 10,000 mGy is compromised. • The decreased fertility among the F{sub 2} progeny is transgenerational phenomenon.

  9. Bacteriophages in the control of pathogenic vibrios

    DEFF Research Database (Denmark)

    Plaza, Nicolás; Castillo Bermúdez, Daniel Elías; Perez-Reytor, Diliana

    2018-01-01

    constitute a continuing threat for aquaculture. Moreover, the continuous use of antibiotics has been accompanied by an emergence of antibiotic resistance in Vibrio species, implying a necessity for efficient treatments. One promising alternative that emerges is the use of lytic bacteriophages; however......, there are some drawbacks that should be overcome to make phage therapy a widely accepted method. In this work, we discuss about the major pathogenic Vibrio species and the progress, benefits and disadvantages that have been detected during the experimental use of bacteriophages to their control....

  10. Autoinducers act as biological timers in Vibrio harveyi

    OpenAIRE

    Anetzberger, C.; Reiger, M.; Fekete, A.; Schell, U.; Stambrau, N.; Plener, L.; Kopka, J.; Schmitt-Kopplin, P.; Hilbi, H.; Jung, K.

    2012-01-01

    Quorum sensing regulates cell density-dependent phenotypes and involves the synthesis, excretion and detection of so-called autoinducers. Vibrio harveyi strain ATCC BAA-1116 (recently reclassified as Vibrio campbellii), one of the best-characterized model organisms for the study of quorum sensing, produces and responds to three autoinducers. HAI-1, AI-2 and CAI-1 are recognized by different receptors, but all information is channeled into the same signaling cascade, which controls a specific ...

  11. Nano-TiO2 enhances the toxicity of copper in natural water to Daphnia magna

    International Nuclear Information System (INIS)

    Fan Wenhong; Cui Minming; Liu Hong; Wang Chuan; Shi Zhiwei; Tan Cheng; Yang Xiuping

    2011-01-01

    The acute toxicity of engineered nanoparticles (NPs) in aquatic environments at high concentrations has been well-established. This study demonstrates that, at a concentration generally considered to be safe in the environment, nano-TiO 2 remarkably enhanced the toxicity of copper to Daphnia magna by increasing the copper bioaccumulation. Specifically, at 2 mg L -1 nano-TiO 2 , the (LC 50 ) of Cu 2+ concentration observed to kill half the population, decreased from 111 μg L -1 to 42 μg L -1 . Correspondingly, the level of metallothionein decreased from 135 μg g -1 wet weight to 99 μg g -1 wet weight at a Cu 2+ level of 100 μg L -1 . The copper was found to be adsorbed onto the nano-TiO 2 , and ingested and accumulated in the animals, thereby causing toxic injury. The nano-TiO 2 may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification by metallothioneins. - Research highlights: → This study demonstrates that, at a concentration generally considered to be safe in the environment, nano-TiO 2 remarkably enhanced the toxicity of copper to Daphnia magna. → The copper was found to be adsorbed onto the nano-TiO 2 , and ingested and accumulated in the Daphnia magna, thereby causing toxic injury. → The nano-TiO 2 may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification mechanism of metallothionein. - The nano-TiO 2 remarkably enhanced the toxicity of copper to Daphnia magna. The nano-TiO 2 may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification mechanism of metallothionein.

  12. Reactions of clofibric acid with oxidative and reductive radicals—Products, mechanisms, efficiency and toxic effects

    International Nuclear Information System (INIS)

    Csay, Tamás; Rácz, Gergely; Salik, Ádám; Takács, Erzsébet; Wojnárovits, László

    2014-01-01

    The degradation of clofibric acid induced by hydroxyl radical, hydrated electron and O 2 −∙ /HO 2 ∙ reactive species was studied in aqueous solutions. Clofibric acid was decomposed more effectively by hydroxyl radical than by hydrated electron or O 2 −∙ /HO 2 ∙ . Various hydroxylated, dechlorinated and fragmentation products have been identified and quantified. A new LC–MS method was developed based on 18 O isotope labeling to follow the formation of hydroxylated derivatives of clofibric acid. Possible degradation pathways have been proposed. The overall degradation was monitored by determination of sum parameters like COD, TOC and AOX. It was found that the organic chlorine degrades very effectively prior to complete mineralization. After the treatment no toxic effect was found according to Vibrio fischeri tests. However, at early stages some of the reaction products were more harmful than clofibric acid. - Highlights: • Clofibric acid is effectively degraded by OH radical. • Main primary and secondary products are hydroxylated and dihydroxylated phenyl type derivatives of clofibric acid. • In air saturated aqueous solutions O 2 plays an important role in decomposition of the aromatic structure. • A new LC–MS method with 18 O-labeling was developed. • Early stage reaction products are more toxic to bacteria Vibrio fischeri than clofibric acid

  13. Toxicity and chemical analyses of airport runoff waters in Poland.

    Science.gov (United States)

    Sulej, Anna Maria; Polkowska, Zaneta; Wolska, Lidia; Cieszynska, Monika; Namieśnik, Jacek

    2014-05-01

    The aim of this study was to assess the ecotoxicological effects of various compounds in complex airport effluents using a chemical and ecotoxicological integrated strategy. The present work deals with the determination of sum of PCBs, PAHs, pesticides, cations, anions, phenols, anionic, cationic, non-ionic detergents, formaldehyde and metals--as well as TOC and conductivity--in runoff water samples collected from 2009 to 2011 at several locations on two Polish international airports. Two microbiotests (Vibrio fischeri bacteria and the crustacean Thamnocephalus platyurus) have been used to determine the ecotoxicity of airport runoff waters. The levels of many compounds exceeded several or even several tens of times the maximum permissible levels. Analysis of the obtained data shows that samples that displayed maximum toxicity towards the bioindicators Vibrio fischeri were not toxic towards Thamnocephalus platyurus. Levels of toxicity towards T. platyurus are strongly correlated with pollutants that originate from the technological operations related to the maintenance of airport infrastructure. The integrated (chemical-ecotoxicological) approach to environmental contamination assessment in and around airports yields extensive information on the quality of the environment. These methodologies can be then used as tools for tracking the environmental fate of these compounds and for assessing the environmental effect of airports. Subsequently, these data will provide a basis for airport infrastructure management.

  14. Daphnia HR96 is a promiscuous xenobiotic and endobiotic nuclear receptor

    International Nuclear Information System (INIS)

    Karimullina, Elina; Li Yangchun; Ginjupalli, Gautam K.; Baldwin, William S.

    2012-01-01

    Daphnia pulex is the first crustacean to have its genome sequenced. The genome project provides new insight and data into how an aquatic crustacean may respond to environmental stressors, including toxicants. We cloned Daphnia pulex HR96 (DappuHR96), a nuclear receptor orthologous to the CAR/PXR/VDR group of nuclear receptors. In Drosophila melanogaster, (hormone receptor 96) HR96 responds to phenobarbital exposure and has been hypothesized as a toxicant receptor. Therefore, we set up a transactivation assay to test whether DappuHR96 is a promiscuous receptor activated by xenobiotics and endobiotics similar to the constitutive androstane receptor (CAR) and the pregnane X-receptor (PXR). Transactivation assays performed with a GAL4-HR96 chimera demonstrate that HR96 is a promiscuous toxicant receptor activated by a diverse set of chemicals such as pesticides, hormones, and fatty acids. Several environmental toxicants activate HR96 including estradiol, pyriproxyfen, chlorpyrifos, atrazine, and methane arsonate. We also observed repression of HR96 activity by chemicals such as triclosan, androstanol, and fluoxetine. Nearly 50% of the chemicals tested activated or inhibited HR96. Interestingly, unsaturated fatty acids were common activators or inhibitors of HR96 activity, indicating a link between diet and toxicant response. The omega-6 and omega-9 unsaturated fatty acids linoleic and oleic acid activated HR96, but the omega-3 unsaturated fatty acids alpha-linolenic acid and docosahexaenoic acid inhibited HR96, suggesting that these two distinct sets of lipids perform opposing roles in Daphnia physiology. This also provides a putative mechanism by which the ratio of dietary unsaturated fats may affect the ability of an organism to respond to a toxic insult. In summary, HR96 is a promiscuous nuclear receptor activated by numerous endo- and xenobiotics.

  15. Daphnia HR96 is a promiscuous xenobiotic and endobiotic nuclear receptor

    Energy Technology Data Exchange (ETDEWEB)

    Karimullina, Elina [Environmental Toxicology Program, Clemson University, Clemson, SC 29634 (United States); Institute of Plant and Animal Ecology, Russian Academy of Sciences, Ural Branch, Yekaterinburg 620144 (Russian Federation); Li Yangchun; Ginjupalli, Gautam K. [Environmental Toxicology Program, Clemson University, Clemson, SC 29634 (United States); Baldwin, William S., E-mail: baldwin@clemson.edu [Environmental Toxicology Program, Clemson University, Clemson, SC 29634 (United States); Biological Sciences, Clemson University, Clemson, SC (United States)

    2012-07-15

    Daphnia pulex is the first crustacean to have its genome sequenced. The genome project provides new insight and data into how an aquatic crustacean may respond to environmental stressors, including toxicants. We cloned Daphnia pulex HR96 (DappuHR96), a nuclear receptor orthologous to the CAR/PXR/VDR group of nuclear receptors. In Drosophila melanogaster, (hormone receptor 96) HR96 responds to phenobarbital exposure and has been hypothesized as a toxicant receptor. Therefore, we set up a transactivation assay to test whether DappuHR96 is a promiscuous receptor activated by xenobiotics and endobiotics similar to the constitutive androstane receptor (CAR) and the pregnane X-receptor (PXR). Transactivation assays performed with a GAL4-HR96 chimera demonstrate that HR96 is a promiscuous toxicant receptor activated by a diverse set of chemicals such as pesticides, hormones, and fatty acids. Several environmental toxicants activate HR96 including estradiol, pyriproxyfen, chlorpyrifos, atrazine, and methane arsonate. We also observed repression of HR96 activity by chemicals such as triclosan, androstanol, and fluoxetine. Nearly 50% of the chemicals tested activated or inhibited HR96. Interestingly, unsaturated fatty acids were common activators or inhibitors of HR96 activity, indicating a link between diet and toxicant response. The omega-6 and omega-9 unsaturated fatty acids linoleic and oleic acid activated HR96, but the omega-3 unsaturated fatty acids alpha-linolenic acid and docosahexaenoic acid inhibited HR96, suggesting that these two distinct sets of lipids perform opposing roles in Daphnia physiology. This also provides a putative mechanism by which the ratio of dietary unsaturated fats may affect the ability of an organism to respond to a toxic insult. In summary, HR96 is a promiscuous nuclear receptor activated by numerous endo- and xenobiotics.

  16. Effects of colonization, luminescence, and autoinducer on host transcription during development of the squid-vibrio association.

    Science.gov (United States)

    Chun, Carlene K; Troll, Joshua V; Koroleva, Irina; Brown, Bartley; Manzella, Liliana; Snir, Einat; Almabrazi, Hakeem; Scheetz, Todd E; Bonaldo, Maria de Fatima; Casavant, Thomas L; Soares, M Bento; Ruby, Edward G; McFall-Ngai, Margaret J

    2008-08-12

    The light-organ symbiosis between the squid Euprymna scolopes and the luminous bacterium Vibrio fischeri offers the opportunity to decipher the hour-by-hour events that occur during the natural colonization of an animal's epithelial surface by its microbial partners. To determine the genetic basis of these events, a glass-slide microarray was used to characterize the light-organ transcriptome of juvenile squid in response to the initiation of symbiosis. Patterns of gene expression were compared between animals not exposed to the symbiont, exposed to the wild-type symbiont, or exposed to a mutant symbiont defective in either of two key characters of this association: bacterial luminescence or autoinducer (AI) production. Hundreds of genes were differentially regulated as a result of symbiosis initiation, and a hierarchy existed in the magnitude of the host's response to three symbiont features: bacterial presence > luminescence > AI production. Putative host receptors for bacterial surface molecules known to induce squid development are up-regulated by symbiont light production, suggesting that bioluminescence plays a key role in preparing the host for bacteria-induced development. Further, because the transcriptional response of tissues exposed to AI in the natural context (i.e., with the symbionts) differed from that to AI alone, the presence of the bacteria potentiates the role of quorum signals in symbiosis. Comparison of these microarray data with those from other symbioses, such as germ-free/conventionalized mice and zebrafish, revealed a set of shared genes that may represent a core set of ancient host responses conserved throughout animal evolution.

  17. Data-directed modelling of Daphnia dynamics in a long-term micro-ecosystem experiment

    NARCIS (Netherlands)

    Grasman, J.; Nes, van E.H.; Kersting, K.

    2009-01-01

    The micro-ecosystem under consideration consists of three compartments forming a closed chain in which water circulates. Three trophic levels are represented in different compartments: autotrophs (algae, mainly Chlorella vulgaris), herbivores (Daphnia magna) and microbial decomposers. From a 20

  18. Carriage of vibrio species by shrimps harvested from the coastal ...

    African Journals Online (AJOL)

    Objectives: To determine the prevalence of Vibrio spp in unprocessed shrimps and their susceptibility to antibiotics. Design: A prospective study of Vibrio spp associated with shrimps harvested from the coastal waters of South West Cameroon. Setting: A laboratory based study at the Department of Life Sciences, University ...

  19. A selective and differential medium for Vibrio harveyi.

    OpenAIRE

    Harris, L; Owens, L; Smith, S

    1996-01-01

    A new medium, termed Vibrio harveyi agar, has been developed for the isolation and enumeration of V. harveyi. It is possible to differentiate V. harveyi colonies from the colonies of strains representing 15 other Vibrio species with this medium. This medium has been shown to inhibit the growth of two strains of marine Pseudomonas spp. and two strains of marine Flavobacterium spp. but to allow the growth of Photobacterium strains. Colonies displaying typical V. harveyi morphology were isolated...

  20. A selective and differential medium for Vibrio harveyi.

    Science.gov (United States)

    Harris, L; Owens, L; Smith, S

    1996-01-01

    A new medium, termed Vibrio harveyi agar, has been developed for the isolation and enumeration of V. harveyi. It is possible to differentiate V. harveyi colonies from the colonies of strains representing 15 other Vibrio species with this medium. This medium has been shown to inhibit the growth of two strains of marine Pseudomonas spp. and two strains of marine Flavobacterium spp. but to allow the growth of Photobacterium strains. Colonies displaying typical V. harveyi morphology were isolated from the larval rearing water of a commercial prawn hatchery with V. harveyi agar as a primary isolation medium and were positively identified, by conventional tests, as V. harveyi. This agar displays great potential as a primary isolation medium and offers significant advantages over thiosulfate-citrate-bile salts-sucrose agar as a medium for differentiating V. harveyi from other marine and estuarine Vibrio species. PMID:8795252

  1. Application of Reverse Transcriptase-PCR-DGGE as a rapid method for routine determination of Vibrio spp. in foods.

    Science.gov (United States)

    Chahorm, Kanchana; Prakitchaiwattana, Cheunjit

    2018-01-02

    The aim of this research was to evaluate the feasibility of PCR-DGGE and Reverse Transcriptase-PCR-DGGE techniques for rapid detection of Vibrio species in foods. Primers GC567F and 680R were initially evaluated for amplifying DNA and cDNA of ten references Vibrio species by PCR method. The GC-clamp PCR amplicons were separated according to their sequences by the DGGE using 10% (w/v) polyacrylamide gel containing 45-70% urea and formamide denaturants. Two pair of Vibrio species, which could not be differentiated on the gel, was Vibrio fluvialis - Vibrio furnissii and Vibrio parahaemolyticus - Vibrio harveyi. To determine the detection limit, in the community of 10 reference strains containing the same viable population, distinct DNA bands of 3 species; Vibrio cholerae, Vibrio mimicus and Vibrio alginolyticus were consistently observed by PCR-DGGE technique. In fact, 5 species; Vibrio cholerae, Vibrio mimicus, Vibrio alginolyticus, Vibrio parahaemolyticus and Vibrio fluvialis consistently observed by Reverse Transcriptase-PCR-DGGE. In the community containing different viable population increasing from 10 2 to 10 5 CFU/mL, PCR-DGGE analysis only detected the two most prevalent species, while RT-PCR-DGGE detected the five most prevalent species. Therefore, Reverse Transcriptase-PCR-DGGE was also selected for detection of various Vibrio cell conditions, including viable cell (VC), injured cells from frozen cultures (IVC) and injured cells from frozen cultures with pre-enrichment (PIVC). It was found that cDNA band of all cell conditions gave the same migratory patterns, except that multiple cDNA bands of Plesiomonas shigelloides under IVC and PIVC conditions were found. When Reverse Transcriptase-PCR-DGGE was used for detecting Vibrio parahaemolyticus in the pathogen-spiked food samples, Vibrio parahaemolyticus could be detected in the spiked samples containing at least 10 2 CFU/g of this pathogen. The results obtained also corresponded to standard method (USFDA, 2004

  2. Ecotoxicity of TiO2 to Daphnia similis under irradiation

    International Nuclear Information System (INIS)

    Marcone, Glauciene P.S.; Oliveira, Ádria C.; Almeida, Gilberto; Umbuzeiro, Gisela A.; Jardim, Wilson F.

    2012-01-01

    Graphical abstract: EC50 (mg L −1 ) values to TiO 2 samples obtained in toxicity tests with Daphnia similis under different conditions of illumination (UV A and visible radiation) and in the dark (as standard protocols). P25: commercial sample containing 30% rutile and 70% anatase; M-S: synthesized sample containing 30% rutile and 70% anatase; Anatase-S: synthesized sample containing 100% anatase; Rutile-S: synthesized sample containing 100% rutile and P25*: commercial sample containing 100% rutile. Highlights: ► Some key physicochemical parameters of nano TiO 2 explain the toxicity observed. ► Under UV A radiation, TiO 2 becomes more toxic to D. similis. ► Toxicity tests of photoactive nano materials require photons as control parameter. - Abstract: Currently, there are a large number of products (sunscreen, pigments, cosmetics, plastics, toothpastes and photocatalysts) that use TiO 2 nanoparticles. Due to this large production, these nanoparticles can be released into the aquatic, terrestrial and aerial environments at relative high concentration. TiO 2 in natural water has the capacity to harm aquatic organisms such as the Daphnia (Cladocera) species, mainly because the photocatalytic properties of this semiconductor. However, very few toxicity tests of TiO 2 nanoparticles have been conducted under irradiation. The aim of this study was to evaluate anatase and rutile TiO 2 toxicity to Daphnia similis exploring their photocatalytic properties by incorporating UV A and visible radiation as a parameter in the assays. Anatase and rutile TiO 2 samples at the highest concentration tested (100 mg L −1 ) were not toxic to D. similis, neither in the dark nor under visible light conditions. The anatase form and a mixture of anatase and rutile, when illuminated by a UV A black light with a peak emission wavelength of 360 nm, presented photo-dependent EC50 values of 56.9–7.8 mg L −1 , which indicates a toxicity mechanism caused by ROS (reactive oxygen species

  3. Effects of UV-B irradiated algae on life history traits of Daphnia pulex

    NARCIS (Netherlands)

    De Lange, H.J.; Van Donk, E.

    1997-01-01

    1. The impact of ultraviolet-B (UVB)-irradiated phytoplankton on the life history parameters of Daphnia was studied. Three species of Chlorophyceae (Chlamydomonas reinhardtii, Scenedesmus acutus and S. subspicatus) and one species of Cryptophyceae (Cryptamonas pyrenoidifera) were cultured with and

  4. Food mediated life history strategies in Daphnia magna : their relevance to ecotoxicological evaluations

    NARCIS (Netherlands)

    Enserink, E.L.

    1995-01-01

    The waterflea Daphnia magna is a widely used test organism in ecotoxicological studies. Acute and chronic laboratory tests yield basic information for the development of water quality standards, assessment of potential hazards of (new) chemicals, waste water licences and

  5. Secreted protein eco-corona mediates uptake and impacts of polystyrene nanoparticles on Daphnia magna.

    Science.gov (United States)

    Nasser, Fatima; Lynch, Iseult

    2016-03-30

    Nanoparticles (NPs) are defined as having at least one external dimension between 1 and 100 nm. Due to their small size, NPs have a large surface area to volume ratio giving them unique characteristics that differ from bulk material of the same chemical composition. As a result these novel materials have found numerous applications in medical and industrial fields with the result that environmental exposure to NPs is increasingly likely. Similarly, increased reliance on plastic, which degrades extremely slowly in the environment, is resulting in increased accumulation of micro-/nano-plastics in fresh and marine waters, whose ecotoxicological impacts are as yet poorly understood. Although NPs are well known to adsorb macromolecules from their environment, forming a biomolecule corona which changes the NP identity and how it interacts with organisms, significantly less research has been performed on the ecological corona (eco-corona). Secretion of biomolecules is a well established predator-prey response in aquatic food chains, raising the question of whether NPs interact with secreted proteins, and the impact of such interaction on NP uptake and ecotoxicity. We report here initial studies, including optimisation of protocols using carboxylic-acid and amino modified spherical polystyrene NPs, to assess interaction of NPs with biomolecules secreted by Daphnia magna and the impact of these interactions on NP uptake, retention and toxicity towards Daphnia magna. Daphnia magna are an important environmental indicator species who may be especially sensitive to nanoparticles (NPs) as a result of being filter-feeders. This paper demonstrates for the first time that proteins released by Daphnia magna create an eco-corona around polystyrene NPs which causes heightened uptake of the NPs and consequently increases toxicity. The secreted protein eco-corona also causes the NPs to be less efficiently removed from the gut of D. magna and NPs remaining in the gut of D. magna

  6. Uptake, retention and internalization of quantum dots in Daphnia is influenced by particle surface functionalization

    Energy Technology Data Exchange (ETDEWEB)

    Feswick, A., E-mail: afeswick@yahoo.ca [Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611 (United States); Canadian Rivers Institute, University of New Brunswick, PO Box 5050, Saint John NB, CA (United States); Griffitt, R.J., E-mail: joe.griffitt@usm.edu [Department of Coastal Sciences, University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564 (United States); Siebein, K., E-mail: kerry.siebein@nist.gov [Major Analytical Instrumentation Center, University of Florida, PO Box 116400, Gainesville, FL 32611 (United States); Barber, D.S., E-mail: barberd@vetmed.ufl.edu [Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611 (United States)

    2013-04-15

    Highlights: ► Daphnia underwent a waterborne exposure of PEG, NH{sub 2} and COOH functionalized quantum dot nanoparticles. ► There was preferential retention of COOH nanoparticles. ► TEM demonstrated that NH{sub 2} and COOH nanoparticles were internalized in cells adjacent to the GI tract. ► This cellular internalization was confirmed using energy dispersive spectroscopy. -- Abstract: Nanomaterials are a diverse group of compounds whose inevitable release into the environment warrants study of the fundamental processes that govern the ingestion, uptake and accumulation in aquatic organisms. Nanomaterials have the ability to transfer to higher trophic levels in aquatic ecosystems, and recent evidence suggests that the surface chemistry of both the nanoparticle and biological membrane can influence uptake kinetics. Therefore, our study investigates the effect of surface functionalization on uptake, internalization and depuration in Daphnia spp. Uncharged (polyethylene glycol; PEG), positively charged (amino-terminated: NH{sub 2}) and negatively charged (carboxyl-modified; COOH) cadmium selenide/zinc sulfide quantum dots were used to monitor ingestion, uptake and depuration of nanometals in Daphnia magna and Ceriodaphnia dubia over 24 h of exposure. These studies demonstrated that particles with higher negative charge (COOH quantum dots) were taken up to a greater extent by Daphnia (259.17 ± 17.70 RFU/20 Daphnia) than either the NH{sub 2} (150.01 ± 18.91) or PEG quantum dots (95.17 ± 9.78), however this is likely related to the functional groups attached to the nanoparticles as there were no real differences in zeta potential. Whole body fluorescence associates well with fluorescent microscopic images obtained at the 24 h timepoint. Confocal and electron microscopic analysis clearly demonstrated that all three types of quantum dots could cross the intestinal epithelial barrier and be translocated to other cells. Upon cessation of exposure, elimination of

  7. Vibrio sp. DSM 14379 pigment production--a competitive advantage in the environment?

    Science.gov (United States)

    Starič, Nejc; Danevčič, Tjaša; Stopar, David

    2010-10-01

    The ability to produce several antibacterial agents greatly increases the chance of producer's survival. In this study, red-pigmented Vibrio sp. DSM 14379 and Bacillus sp., both isolated from the same sampling volume from estuarine waters of the Northern Adriatic Sea, were grown in a co-culture. The antibacterial activity of the red pigment extract was tested on Bacillus sp. in microtiter plates. The MIC(50) for Bacillus sp. was estimated to be around 10⁻⁵ mg/L. The extract prepared form the nonpigmented mutant of Vibrio sp. had no antibacterial effect. The pigment production of Vibrio sp. was studied under different physicochemical conditions. There was no pigment production at high or low temperatures, high or low salt concentrations in peptone yeast extract (PYE) medium, low glucose concentration in mineral growth medium or high glucose concentration in PYE medium. This indicates that the red pigment production is a luxurious good that Vibrio sp. makes only under favorable conditions. The Malthusian fitness of Bacillus sp. in a co-culture with Vibrio sp. under optimal environmental conditions dropped from 4.0 to -7.6, which corresponds to three orders of magnitude decrease in the number of CFU relative to the monoculture. The nonpigmented mutant of Vibrio sp. in a co-culture with Bacillus sp. had a significant antibacterial activity. This result shows that studying antibacterial properties in isolation (i.e. pigment extract only) may not reveal full antibacterial potential of the bacterial strain. The red pigment is a redundant antibacterial agent of Vibrio sp.

  8. Effects of cell-bound microcystins on survival and feeding of Daphnia spp

    DEFF Research Database (Denmark)

    Rohrlack, T; Dittmann, E; Börner, T

    2001-01-01

    The influence of cell-bound microcystins on the survival time and feeding rates of six Daphnia clones belonging to five common species was studied. To do this, the effects of the microcystin-producing Microcystis strain PCC7806 and its mutant, which has been genetically engineered to knock out mi...

  9. Heavy metal concentrations and toxicity in water and sediment from stormwater ponds and sedimentation tanks

    OpenAIRE

    Karlsson, Kristin; Viklander, Maria; Scholes, Lian N. L.; Revitt, D. Mike

    2010-01-01

    Sedimentation is a widely used technique in structural best management practices to remove pollutants from stormwater. However, concerns have been expressed about the environmental impacts that may be exerted by the trapped pollutants. This study has concentrated on stormwater ponds and sedimentation tanks and reports on the accumulated metal concentrations (Cd, Cr, Ni, Pb, and Zn) and the associated toxicity to the bacteria Vibrio fischeri. The metal concentrations are compared with guidelin...

  10. Vibrios patogênicos em ostras (Crassostrea rhizophorae servidas em restaurantes no Rio de Janeiro: um alerta para a Saúde Pública Pathogenic Vibrios in oysters (Crassostrea rhizophorae served at restaurants in Rio de Janeiro: a public health warning

    Directory of Open Access Journals (Sweden)

    Christiane Soares Pereira

    2007-06-01

    Full Text Available Avaliaram-se 40 amostras de ostras (Crassostrea rhizophorae servidas in natura em 15 restaurantes da Cidade do Rio de Janeiro, a fim de investigar a presença de Vibrio spp. As amostras de ostras foram analisadas e submetidas a enriquecimento em água peptonada alcalina adicionada de 1 e 3% de NaCl, incubadas a 37°C por 24 horas. Em seguida, os cultivos foram semeados em agar tiossulfato citrato bile sacarose e as colônias suspeitas foram submetidas à caracterização bioquímica. Vibrio parahaemolyticus, Vibrio carchariae, Vibrio alginolyticus e Vibrio vulnificus representaram as principais espécies (> 60% isoladas a partir das ostras in natura.Forty oyster samples (Crassostrea rhizophorae served raw in 15 restaurants in the city of Rio de Janeiro were evaluated in order to investigate the presence of Vibrio spp. The oyster samples were analyzed and subjected to enrichment in alkaline peptone water with the addition of 1 and 3% NaCl and incubated at 37°C for 24 hours. Following this, the cultures were seeded onto thiosulfate citrate bile sucrose agar (TCBS and the suspected colonies were subjected to biochemical characterization. Vibrio parahaemolyticus, Vibrio carchariae, Vibrio alginolyticus and Vibrio vulnificus were the main species (> 60% isolated from raw oysters.

  11. Proteomics Analysis Reveals Previously Uncharacterized Virulence Factors in Vibrio proteolyticus

    Directory of Open Access Journals (Sweden)

    Ann Ray

    2016-07-01

    Full Text Available Members of the genus Vibrio include many pathogens of humans and marine animals that share genetic information via horizontal gene transfer. Hence, the Vibrio pan-genome carries the potential to establish new pathogenic strains by sharing virulence determinants, many of which have yet to be characterized. Here, we investigated the virulence properties of Vibrio proteolyticus, a Gram-negative marine bacterium previously identified as part of the Vibrio consortium isolated from diseased corals. We found that V. proteolyticus causes actin cytoskeleton rearrangements followed by cell lysis in HeLa cells in a contact-independent manner. In search of the responsible virulence factor involved, we determined the V. proteolyticus secretome. This proteomics approach revealed various putative virulence factors, including active type VI secretion systems and effectors with virulence toxin domains; however, these type VI secretion systems were not responsible for the observed cytotoxic effects. Further examination of the V. proteolyticus secretome led us to hypothesize and subsequently demonstrate that a secreted hemolysin, belonging to a previously uncharacterized clan of the leukocidin superfamily, was the toxin responsible for the V. proteolyticus-mediated cytotoxicity in both HeLa cells and macrophages. Clearly, there remains an armory of yet-to-be-discovered virulence factors in the Vibrio pan-genome that will undoubtedly provide a wealth of knowledge on how a pathogen can manipulate host cells.

  12. Emergent Patterns of Diversity and Dynamics in Natural Populations of Planktonic Vibrio Bacteria

    Science.gov (United States)

    2005-06-01

    1973. Ecology of Vibrio parahemolyticus in mixed-template amplifications: formation, consequences and elimination by Chesapeake Bay. J. Bacteriol. 113...Science 1930 and Engineering DOCTORAL DISSERTATION Emergent Patterns of Diversity and Dynamics in Natural Populations of Planktonic Vibrio Bacteria by...DYNAMICS IN NATURAL POPULATIONS OF PLANKTONIC VIBRIO BACTERIA by Janelle Ren6e Thompson B.S. Biological Sciences, Stanford University 1998 M.S

  13. Symbiotic association of Photobacterium fischeri with the marine luminous fish Monocentris japonica; a model of symbiosis based on bacterial studies.

    Science.gov (United States)

    Ruby, E G; Nealson, K H

    1976-12-01

    Isolation of bacteria from the luminous organ of the fish Monocentris japonica has revealed that the organ contains a pure culture of luminous bacteria. For the four fish examined, all contained Photobacterium fischeri as their luminous bacterial symbiont. This is the first time that P. fischeri has been identified in a symbiotic association. A representative isolate (MJl) of the light organ population was selected for in vivo studies of its luminous system. Several physiological features suggest adaptation for symbiotic existence. First, MJl has been shown to produce and respond to an inducer of luciferase that could accumulate in the light organ. Secondly, the specific activity of light production was seen to be maximal under low, growth-limiting concentrations of oxygen. Thirdly, unlike another luminous species (Beneckea harveyi), synthesis of the light production system of these bacteria is not catabolite repressed by glucose--a possible source of nutrition in the light organ. Fourthly, when grown aerobically on glucose these bacteria excrete pyruvic acid into the medium. This production of pyruvate is a major process, accounting for 30-40% of the glucose utilized and may serve as a form of regulatory and nutritional communication with the host.

  14. Vibrio Pathogens: A Public Health Concern in Rural Water Resources in Sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Charles A. Osunla

    2017-10-01

    Full Text Available Members of the Vibrio genus are autochthonous inhabitants of aquatic environments and play vital roles in sustaining the aquatic milieu. The genus comprises about 100 species, which are mostly of marine or freshwater origin, and their classification is frequently updated due to the continuous discovery of novel species. The main route of transmission of Vibrio pathogens to man is through drinking of contaminated water and consumption inadequately cooked aquatic food products. In sub-Saharan Africa and much of the developing world, some rural dwellers use freshwater resources such as rivers for domestic activities, bathing, and cultural and religious purposes. This review describes the impact of inadequately treated sewage effluents on the receiving freshwater resources and the associated risk to the rural dwellers that depends on the water. Vibrio infections remain a threat to public health. In the last decade, Vibrio disease outbreaks have created alertness on the personal, economic, and public health uncertainties associated with the impact of contaminated water in the aquatic environment of sub-Saharan Africa. In this review, we carried out an overview of Vibrio pathogens in rural water resources in Sub-Saharan Africa and the implication of Vibrio pathogens on public health. Continuous monitoring of Vibrio pathogens among environmental freshwater and treated effluents is expected to help reduce the risk associated with the early detection of sources of infection, and also aid our understanding of the natural ecology and evolution of Vibrio pathogens.

  15. Vibrio Pathogens: A Public Health Concern in Rural Water Resources in Sub-Saharan Africa.

    Science.gov (United States)

    Osunla, Charles A; Okoh, Anthony I

    2017-10-07

    Members of the Vibrio genus are autochthonous inhabitants of aquatic environments and play vital roles in sustaining the aquatic milieu. The genus comprises about 100 species, which are mostly of marine or freshwater origin, and their classification is frequently updated due to the continuous discovery of novel species. The main route of transmission of Vibrio pathogens to man is through drinking of contaminated water and consumption inadequately cooked aquatic food products. In sub-Saharan Africa and much of the developing world, some rural dwellers use freshwater resources such as rivers for domestic activities, bathing, and cultural and religious purposes. This review describes the impact of inadequately treated sewage effluents on the receiving freshwater resources and the associated risk to the rural dwellers that depends on the water. Vibrio infections remain a threat to public health. In the last decade, Vibrio disease outbreaks have created alertness on the personal, economic, and public health uncertainties associated with the impact of contaminated water in the aquatic environment of sub-Saharan Africa. In this review, we carried out an overview of Vibrio pathogens in rural water resources in Sub-Saharan Africa and the implication of Vibrio pathogens on public health. Continuous monitoring of Vibrio pathogens among environmental freshwater and treated effluents is expected to help reduce the risk associated with the early detection of sources of infection, and also aid our understanding of the natural ecology and evolution of Vibrio pathogens.

  16. Vibrio Pathogens: A Public Health Concern in Rural Water Resources in Sub-Saharan Africa

    Science.gov (United States)

    Osunla, Charles A.

    2017-01-01

    Members of the Vibrio genus are autochthonous inhabitants of aquatic environments and play vital roles in sustaining the aquatic milieu. The genus comprises about 100 species, which are mostly of marine or freshwater origin, and their classification is frequently updated due to the continuous discovery of novel species. The main route of transmission of Vibrio pathogens to man is through drinking of contaminated water and consumption inadequately cooked aquatic food products. In sub-Saharan Africa and much of the developing world, some rural dwellers use freshwater resources such as rivers for domestic activities, bathing, and cultural and religious purposes. This review describes the impact of inadequately treated sewage effluents on the receiving freshwater resources and the associated risk to the rural dwellers that depends on the water. Vibrio infections remain a threat to public health. In the last decade, Vibrio disease outbreaks have created alertness on the personal, economic, and public health uncertainties associated with the impact of contaminated water in the aquatic environment of sub-Saharan Africa. In this review, we carried out an overview of Vibrio pathogens in rural water resources in Sub-Saharan Africa and the implication of Vibrio pathogens on public health. Continuous monitoring of Vibrio pathogens among environmental freshwater and treated effluents is expected to help reduce the risk associated with the early detection of sources of infection, and also aid our understanding of the natural ecology and evolution of Vibrio pathogens. PMID:28991153

  17. Epidemiology of a Daphnia-multiparasite system and its implications for the red queen.

    Science.gov (United States)

    Auld, Stuart K J R; Hall, Spencer R; Duffy, Meghan A

    2012-01-01

    The Red Queen hypothesis can explain the maintenance of host and parasite diversity. However, the Red Queen requires genetic specificity for infection risk (i.e., that infection depends on the exact combination of host and parasite genotypes) and strongly virulent effects of infection on host fitness. A European crustacean (Daphnia magna)--bacterium (Pasteuria ramosa) system typifies such specificity and high virulence. We studied the North American host Daphnia dentifera and its natural parasite Pasteuria ramosa, and also found strong genetic specificity for infection success and high virulence. These results suggest that Pasteuria could promote Red Queen dynamics with D. dentifera populations as well. However, the Red Queen might be undermined in this system by selection from a more common yeast parasite (Metschnikowia bicuspidata). Resistance to the yeast did not correlate with resistance to Pasteuria among host genotypes, suggesting that selection by Metschnikowia should proceed relatively independently of selection by Pasteuria.

  18. Ozone Technology for Pathogenic Bacteria of Shrimp (Vibrio sp.) Disinfection

    Science.gov (United States)

    Wulansarie, Ria; Dyah Pita Rengga, Wara; Rustamadji

    2018-03-01

    One of important marine commodities in Indonesia, shrimps are susceptible with Vibrio sp bacteria infection. That infection must be cleared. One of the technologies for disinfecting Vibrio sp. is ozone technology. In this research, Vibrio sp. is a pathogenic bacterium which infects Penaeus vannamei. Ozone technology is applied for threatening Vibrio sp. In this research, ozonation was performed in different pH. Those are neutral, acid (pH=4), and base (pH=9). The sample was water from shrimp embankment from Balai Besar Perikanan Budidaya Air Payau (BBPBAP) located in Jepara. That water was the habitat of Penaeus vannamei shrimp. The brand of ozonator used in this research was “AQUATIC”. The used ozonator in this research had 0,0325 g/hour concentration. The flow rate of sample used in this research was 2 L/minute. The ozonation process was performed in continuous system. A tank, pipe, pump, which was connected with microfilter, flowmeter and ozone generator were the main tools in this research. It used flowmeter and valve to set the flow rate scalable as desired. The first step was the insert of 5 L sample into the receptacle. Then, by using a pump, a sample supplied to the microfilter to be filtered and passed into the flow meter. The flow rate was set to 2 LPM. Furthermore, gas from ozonator passed to the flow for the disinfection of bacteria and then was recycled to the tank and the process run continuously. Samples of the results of ozonation were taken periodically from time 0, 3, 7, 12, 18, 24 to 30 minutes. The samples of the research were analyzed using Total Plate Count (TPC) test in BBPBAP Jepara to determine the number of Vibrio sp. bacteria. The result of this research was the optimal condition for pathogenic bacteria of shrimp (Vibrio sp.) ozonation was in neutral condition.

  19. Insights into bacteriophage application in controlling Vibrio species

    Directory of Open Access Journals (Sweden)

    Vengadesh Letchumanan

    2016-07-01

    Full Text Available Bacterial infections from various organisms including Vibrio sp. pose a serious hazard to humans in many forms from clinical infection to affecting the yield of agriculture and aquaculture via infection of livestock. Vibrio sp. is one of the main foodborne pathogens causing human infection and is also a common cause of losses in the aquaculture industry. Prophylactic and therapeutic usage of antibiotics has become the mainstay of managing this problem, however this in turn led to the emergence of multidrug resistant strains of bacteria in the environment; which has raised awareness of the critical need for alternative non antibiotic based methods of preventing and treating bacterial infections. Bacteriophages - viruses that infect and result in the death of bacteria – are currently of great interest as a highly viable alternative to antibiotics. This article provides an insight into bacteriophage application in controlling Vibrio species as well underlining the advantages and drawbacks of phage therapy.

  20. Natural transformation of Vibrio parahaemolyticus: A rapid method to create genetic deletions.

    Science.gov (United States)

    Chimalapati, Suneeta; de Souza Santos, Marcela; Servage, Kelly; De Nisco, Nicole J; Dalia, Ankur B; Orth, Kim

    2018-03-19

    The Gram-negative bacterium Vibrio parahaemolyticus is an opportunistic human pathogen and the leading cause of seafood borne acute gastroenteritis worldwide. Recently, this bacterium was implicated as the etiologic agent of a severe shrimp disease with consequent devastating outcomes to shrimp farming. In both cases, acquisition of genetic material via horizontal transfer provided V. parahaemolyticus with new virulence tools to cause disease. Dissecting the molecular mechanisms of V. parahaemolyticus pathogenesis often requires manipulating its genome. Classically, genetic deletions in V. parahaemolyticus are performed using a laborious, lengthy, multi-step process. Herein, we describe a fast and efficient method to edit this bacterium's genome based on V. parahaemolyticus natural competence. Although this method is similar to one previously described, V. parahaemolyticus requires counter selection for curing of acquired plasmids due to its recalcitrant nature of retaining extrachromosomal DNA. We believe this approach will be of use to the Vibrio community. Importance Spreading of Vibrios throughout the world correlates with increased global temperatures. As they spread, they find new niches to survive, proliferate and invade. Therefore, genetic manipulation of Vibrios is of utmost importance for studying these species. Herein, we have delineated and validated a rapid method to create genetic deletions in Vibrio parahaemolyticus This study provides insightful methodology for studies with other Vibrio species. Copyright © 2018 American Society for Microbiology.

  1. Bactericidal effect of lactoferrin and lactoferrin chimera against halophilic Vibrio parahaemolyticus

    NARCIS (Netherlands)

    Leon-Sicairos, N.; Canizalez-Roman, A.; de la Garza, M.; Reyes-Lopez, M.; Zazueta-Beltran, J.; Nazmi, K.; Gomez-Gil, B.; Bolscher, J.G.

    2009-01-01

    Infections caused by Vibrio parahaemolyticus, an halophilic member of the genus Vibrio, have increased globally in the last 5 years. Diarrhea caused by V. parahaemolyticus results from eating raw or undercooked seafood. The aim of this work was to investigate whether lactoferrin and some

  2. Effects of medium renewal and handling stress on life history traits in Daphnia

    NARCIS (Netherlands)

    Rousseaux, S.; Vanoverbeke, J.; Aerts, J.; Declerck, S.A.J.

    2010-01-01

    The zooplankton genus Daphnia is used as a model organism in ecological, ecotoxicological and evolutionary research. It is often used in experimental laboratory setups to examine life history traits under a variety of factors inducing stress. One type of stress, handling stress because of

  3. Vibrio parahaemolyticus: A Review on the Pathogenesis, Prevalence and Advance Molecular Identification Techniques

    Directory of Open Access Journals (Sweden)

    Vengadesh eLetchumanan

    2014-12-01

    Full Text Available Vibrio parahaemolyticus is a Gram-negative halophilic bacterium that is found in estuarine, marine and coastal environments. Vibrio parahaemolyticus is the leading causal agent of human acute gastroenteritis following the consumption of raw, undercooked or mishandled marine products. In rare cases, Vibrio parahaemolyticus causes wound infection, ear infection or septicaemia in individuals with pre-existing medical conditions. Vibrio parahaemolyticus has two hemolysins virulence factors that are thermostable direct hemolysin (tdh-a pore-forming protein that contributes to the invasiveness of the bacterium in humans, and TDH-related hemolysin (trh, which plays a similar role as thermostable direct hemolysin (tdh in the disease pathogenesis. In addition, the bacterium is also encodes for adhesions and type III secretion systems (T3SS1 and T3SS2 to ensure its survival in the environment. This review aims at discussing the Vibrio parahemolyticus growth and characteristics, pathogenesis, prevalence and advances in molecular identification techniques.

  4. Mimicking Daphnia magna bioassay performance by an electronic tongue for urban water quality control

    Energy Technology Data Exchange (ETDEWEB)

    Kirsanov, Dmitry, E-mail: d.kirsanov@gmail.com [Laboratory of Chemical Sensors, St. Petersburg State University, St. Petersburg (Russian Federation); Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation); Legin, Evgeny [Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation); Sensor Systems LLC, St. Petersburg (Russian Federation); Zagrebin, Anatoly; Ignatieva, Natalia; Rybakin, Vladimir [Institute of Limnology, Russian Academy of Sciences, St. Petersburg (Russian Federation); Legin, Andrey [Laboratory of Chemical Sensors, St. Petersburg State University, St. Petersburg (Russian Federation); Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation)

    2014-05-01

    Highlights: • -Daphnia magna bioassay can be simulated with multisensor system. • Urban water toxicity can be predicted from potentiometric ET data. • Independent test set validation confirms statistical significance of the results. - Abstract: Toxicity is one of the key parameters of water quality in environmental monitoring. However, being evaluated as a response of living beings (as their mobility, fertility, death rate, etc.) to water quality, toxicity can only be assessed with the help of these living beings. This imposes certain restrictions on toxicity bioassay as an analytical method: biotest organisms must be properly bred, fed and kept under strictly regulated conditions and duration of tests can be quite long (up to several days), thus making the whole procedure the prerogative of the limited number of highly specialized laboratories. This report describes an original application of potentiometric multisensor system (electronic tongue) when the set of electrochemical sensors was calibrated against Daphnia magna death rate in order to perform toxicity assessment of urban waters without immediate involvement of living creatures. PRM (partial robust M) and PLS (projections on latent structures) regression models based on the data from this multisensor system allowed for prediction of toxicity of unknown water samples in terms of biotests but in the fast and simple instrumental way. Typical errors of water toxicity predictions were below 20% in terms of Daphnia death rate which can be considered as a good result taking into account the complexity of the task.

  5. Prevalence and Antimicrobial Resistance of Vibrio spp. in Retail and Farm Shrimps in Ecuador.

    Science.gov (United States)

    Sperling, L; Alter, T; Huehn, S

    2015-11-01

    The aim of this study was to investigate the prevalence of Vibrio spp. in shrimp at retail and in shrimp farms in Ecuador and to determine the antimicrobial agent resistance patterns of farm isolates. The presence of genes linked to early mortality syndrome (EMS) or acute hepatopancreatic necrosis disease (AHPND) also was evaluated. Vibrio spp. were isolated from retail shrimps in Cuenca, Ecuador, and farm shrimps originating from provinces El Oro and Guayas, Ecuador. A total of 229 shrimp samples were collected, of which 71 originated from retail markets in Cuenca and 158 came from shrimp farms. Overall, 219 (95.6%) samples tested positive for Vibrio spp. Vibrio parahaemolyticus (80.8%) was the most common species detected, followed by Vibrio alginolyticus (50.2%), Vibrio cholerae (11.3%), and Vibrio vulnificus (3.5%). None of the V. parahaemolyticus isolates carried the virulence-associated tdh and trh genes. In V. parahaemolyticus shrimp farm isolates, high resistance was found to ampicillin (92.2%), and intermediate resistance was found to tetracycline (51.3%) and amikacin (22.1%). Of the V. parahaemolyticus strains, 68 were resistant to at least three antimicrobial agents, and 2 were resistant to seven antimicrobial agents simultaneously. Up to 18 resistant isolates were found for V. alginolyticus, whereas V. vulnificus and V. cholerae isolates were more susceptible. None of the V. parahaemolyticus isolates carried the EMS-AHPND plasmid. The results of this study revealed the ubiquitous occurrence of Vibrio spp. in shrimps at retail and on shrimp farms in Ecuador.

  6. Effect of soil properties on the toxicity of Pb: assessment of the appropriateness of guideline values.

    Science.gov (United States)

    Romero-Freire, A; Martin Peinado, F J; van Gestel, C A M

    2015-05-30

    Soil contamination with lead is a worldwide problem. Pb can cause adverse effects, but its mobility and availability in the terrestrial environment are strongly controlled by soil properties. The present study investigated the influence of different soil properties on the solubility of lead in laboratory spiked soils, and its toxicity in three bioassays, including Lactuca sativa root elongation and Vibrio fischeri illumination tests applied to aqueous extracts and basal soil respiration assays. Final aim was to compare soil-dependent toxicity with guideline values. The L. sativa bioassay proved to be more sensitive to Pb toxicity than the V. fischeri and soil respiration tests. Toxicity was significantly correlated with soil properties, with soil pH, carbonate and organic carbon content being the most important factors. Therefore, these variables should be considered when defining guideline values. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Maternal effects of inducible tolerance against the toxic cyanobacterium Microcystis aeruginosa in the grazer Daphnia carinata

    International Nuclear Information System (INIS)

    Jiang, Xiaodong; Yang, Wei; Zhao, Shiye; Liang, Huishuang; Zhao, Yunlong; Chen, Liqiao; Li, Rui

    2013-01-01

    Cyanobacterial blooms are becoming potent agents of natural selection in aquatic ecosystems because of their high production of some toxins and increased frequency in recent decades with eutrophication and climate change. Maternal exposure to the toxic Microcystis aeruginosa significantly increased the intrinsic rates of population increase, average life span, and net reproductive rates of a clone of the planktonic grazer Daphnia carinata in an offspring environment where cyanobacteria were present, but not for two additional clones. Offspring from mothers exposed to M. aeruginosa had lower intrinsic rates of population increase, average life span, and net reproductive rates than individuals from unexposed mothers when fed exclusively a green alga. These results suggest that benefits, costs, and clonal variations of maternal effects of inducible tolerance should be considered when trying to understand ecological consequences of cyanobacterial blooms since they can shape the trophic interactions between cyanobacteria and daphnids. -- Highlights: •Maternal exposure to Microcystis aeruginosa significantly increased the offspring tolerance in a Daphnia carinata clone. •Another two clones, however, failed to response to maternal exposure. •Offspring from exposed mothers had lower fitness when fed exclusively a green alga. -- Capsule: Maternal exposure to the toxic Microcystis aeruginosa increased offspring fitness in one of three Daphnia carinata clones and carried a cost

  8. Spatiotemporal Dynamics of Total Viable Vibrio spp. in a NW Mediterranean Coastal Area.

    Science.gov (United States)

    Girard, Léa; Peuchet, Sébastien; Servais, Pierre; Henry, Annabelle; Charni-Ben-Tabassi, Nadine; Baudart, Julia

    2017-09-27

    A cellular approach combining Direct Viable Counting and Fluorescent In Situ Hybridization using a one-step multiple-probe technique and Solid Phase Cytometry (DVC-FISH-SPC) was developed to monitor total viable vibrios and cover the detection of a large diversity of vibrios. FISH combined three probes in the same assay and targeted sequences located at different positions on the 16S rRNA of Vibrio and Aliivibrio members. We performed a 10-month in situ study to investigate the weekly dynamics of viable vibrios relative to culturable counts at two northwestern Mediterranean coastal sites, and identified the key physicochemical factors for their occurrence in water using a multivariate analysis. Total viable and culturable cell counts showed the same temporal pattern during the warmer season, whereas the ratios between both methods were inverted during the colder seasons (<15°C), indicating that some of the vibrio community had entered into a viable but non-culturable (VBNC) state. We confirmed that Seawater Surface Temperature explained 51-62% of the total variance in culturable counts, and also showed that the occurrence of viable vibrios is controlled by two variables, pheopigment (15%) and phosphate (12%) concentrations, suggesting that other unidentified factors play a role in maintaining viability.

  9. Synergistic Effects of Different Food Species on Life-History Traits of Daphnia-Galeata

    NARCIS (Netherlands)

    Boersma, M.; Vijverberg, J.

    1995-01-01

    In this paper we describe the life history consequences of feeding Daphnia galeata with different food types in different concentrations. We fed the animals with four concentrations of two green algae Scenedesmus obliquus and Chlamydomonas globosa, given separately as well as in a 1:1 mixture.

  10. Obesogens beyond Vertebrates: Lipid Perturbation by Tributyltin in the Crustacean Daphnia magna

    Science.gov (United States)

    Jordão, Rita; Casas, Josefina; Fabrias, Gemma; Campos, Bruno; Piña, Benjamín; Lemos, Marco F.L.; Soares, Amadeu M.V.M.; Tauler, Romà

    2015-01-01

    Background The analysis of obesogenic effects in invertebrates is limited by our poor knowledge of the regulatory pathways of lipid metabolism. Recent data from the crustacean Daphnia magna points to three signaling hormonal pathways related to the molting and reproductive cycles [retinoic X receptor (RXR), juvenile hormone (JH), and ecdysone] as putative targets for exogenous obesogens. Objective The present study addresses the disruptive effects of the model obesogen tributyltin (TBT) on the lipid homeostasis in Daphnia during the molting and reproductive cycle, its genetic control, and health consequences of its disruption. Methods D. magna individuals were exposed to low and high levels of TBT. Reproductive effects were assessed by Life History analysis methods. Quantitative and qualitative changes in lipid droplets during molting and the reproductive cycle were studied using Nile red staining. Lipid composition and dynamics were analyzed by ultra-performance liquid chromatography coupled to a time-of-flight mass spectrometer. Relative abundances of mRNA from different genes related to RXR, ecdysone, and JH signaling pathways were studied by qRT-PCR. Results and Conclusions TBT disrupted the dynamics of neutral lipids, impairing the transfer of triacylglycerols to eggs and hence promoting their accumulation in adult individuals. TBT’s disruptive effects translated into a lower fitness for offspring and adults. Co-regulation of gene transcripts suggests that TBT activates the ecdysone, JH, and RXR receptor signaling pathways, presumably through the already proposed interaction with RXR. These findings indicate the presence of obesogenic effects in a nonvertebrate species. Citation Jordão R, Casas J, Fabrias G, Campos B, Piña B, Lemos MF, Soares AM, Tauler R, Barata C. 2015. Obesogens beyond vertebrates: lipid perturbation by tributyltin in the crustacean Daphnia magna. Environ Health Perspect 123:813–819; http://dx.doi.org/10.1289/ehp.1409163 PMID

  11. Epidemiology of a Daphnia-multiparasite system and its implications for the red queen.

    Directory of Open Access Journals (Sweden)

    Stuart K J R Auld

    Full Text Available The Red Queen hypothesis can explain the maintenance of host and parasite diversity. However, the Red Queen requires genetic specificity for infection risk (i.e., that infection depends on the exact combination of host and parasite genotypes and strongly virulent effects of infection on host fitness. A European crustacean (Daphnia magna--bacterium (Pasteuria ramosa system typifies such specificity and high virulence. We studied the North American host Daphnia dentifera and its natural parasite Pasteuria ramosa, and also found strong genetic specificity for infection success and high virulence. These results suggest that Pasteuria could promote Red Queen dynamics with D. dentifera populations as well. However, the Red Queen might be undermined in this system by selection from a more common yeast parasite (Metschnikowia bicuspidata. Resistance to the yeast did not correlate with resistance to Pasteuria among host genotypes, suggesting that selection by Metschnikowia should proceed relatively independently of selection by Pasteuria.

  12. Vibriophages and Their Interactions with the Fish Pathogen Vibrio anguillarum

    DEFF Research Database (Denmark)

    Tan, Demeng; Gram, Lone; Middelboe, Mathias

    2014-01-01

    Vibrio anguillarum is an important pathogen in aquaculture, responsible for the disease vibriosis in many fish and invertebrate species. Disease control by antibiotics is a concern due to potential development and spread of antibiotic resistance. The use of bacteriophages to control the pathogen...... patterns of the individual host isolates, key phenotypic properties related to phage susceptibility are distributed worldwide and maintained in the global Vibrio community for decades. The phage susceptibility pattern of the isolates did not show any relation to the physiological relationships obtained...... from Biolog GN2 profiles, demonstrating that similar phage susceptibility patterns occur across broad phylogenetic and physiological differences in Vibrio strains. Subsequent culture experiments with two phages and two V. anguillarum hosts demonstrated an initial strong lytic potential of the phages...

  13. Prevalence of potentially pathogenic Vibrio species in the seafood marketed in Malaysia.

    Science.gov (United States)

    Elhadi, Nasreldin; Radu, Son; Chen, Chien-Hsien; Nishibuchi, Mitsuaki

    2004-07-01

    Seafood samples obtained in seafood markets and supermarkets at 11 sites selected from four states in Malaysia were examined for the presence of nine potentially pathogenic species from the genus Vibrio between July 1998 and June 1999. We examined 768 sample sets that included shrimp, squid, crab, cockles, and mussels. We extensively examined shrimp samples from Selangor State to determine seasonal variation of Vibrio populations. Eight potentially pathogenic Vibrio species were detected, with overall incidence in the samples at 4.6% for V. cholerae, 4.7% for V. parahaemolyticus, 6.0% for V. vulnificus, 11% for V. alginolyticus, 9.9% for V. metschnikovii, 1.3% for V. mimicus, 13% for V. damsela, 7.6% for V. fluvialis, and 52% for a combined population of all of the above. As many as eight Vibrio species were detected in shrimp and only four in squid and peel mussels. The overall percent incidence of any of the eight vibrios was highest (82%) in cockles (Anadara granosa) among the seafoods examined and was highest (100%) in Kuching, Sarawak State, and lowest (25%) in Penang, Pulau Penang State, among the sampling sites. Of 97 strains of V. cholerae isolated, one strain belonged to the O1 serotype and 14 to the O139 serotype. The results indicate that the various seafood markets in Malaysia are contaminated with potentially pathogenic Vibrio species regardless of the season and suggest that there is a need for adequate consumer protection measures.

  14. Vibrio parahemolyticus septicaemia in a liver transplant patient: a case report

    OpenAIRE

    Fairweather Morgan G; Krishnan Sujatha; Fernando Rajeev R; Ericsson Charles D

    2011-01-01

    Abstract Introduction Vibrio parahemolyticus is the leading cause of vibrio-associated gastroenteritis in the United States of America, usually related to poor food handling; only rarely has it been reported to cause serious infections including sepsis and soft tissue infections. In contrast, Vibrio vulnificus is a well-known cause of septicaemia, especially in patients with cirrhosis. We present a patient with V. parahemolyticus sepsis who had an orthotic liver transplant in 2007 and was on ...

  15. Daphnia as a model organism in limnology and aquatic biology: some aspects of its reproduction and development

    Directory of Open Access Journals (Sweden)

    Adam Petrusek

    2011-08-01

    Full Text Available Invertebrates comprise the overwhelming majority of all animal species - around 95% of described species, not including substantial cryptic variation. As it is an extremely diverse and heterogeneous group, research on various invertebrate taxa often follows parallel trajectories, with little interaction among experts on different groups. To promote sharing of knowledge within as well as across taxa, the International Society of Invertebrate Reproduction and Development (ISIRD was established in 1975 in Calicut, India. Since that time, the ISIRD has organised international conferences at three-year intervals where various aspects of invertebrate biology are presented and discussed, naturally with the focus on reproduction and development. Traditionally, marine invertebrate groups have been well represented at all ISIRD congresses, but freshwater invertebrates have often been relatively overlooked at these meetings. The 12th ISIRD congress took place between August 16 and 20, 2010 in Prague, the Czech Republic. Several different Czech institutions collaborated on the organisation of this meeting. As aquatic invertebrate research has a long tradition in the country, we decided to include a section dedicated to popular model organisms in aquatic ecology and evolutionary biology, the "water fleas", cladocerans of the genus Daphnia. The section entitled "Daphnia and other cladocerans as model organisms" was open to any aspects of cladoceran biology directly or indirectly related to their reproduction or development. Unfortunately, the timing of the Prague congress completely overlapped the triennial congress of the International Society of Theoretical and Applied Limnology (SIL in Cape Town, South Africa. This large meeting in a very attractive setting attracted many cladocerologists from all over the world, including Europe. Therefore, the Daphnia section of the Prague ISIRD meeting remained moderate in size, attracting 13 contributions (eight talks

  16. Distribution ofVibrio cholerae in two Florida estuaries.

    Science.gov (United States)

    Hood, M A; Ness, G E; Rodrick, G E; Blake, N J

    1983-04-01

    The distribution ofVibrio cholerae was examined in 2 Florida estuaries, Apalachicola and Tampa Bay.Vibrio cholerae serotype non-01 was the most abundant serotype, being isolated from 45% of the oyster samples, 30% of the sediments, 50% of the waters, and 75% of the blue crabs.Vibrio cholerae serotype 01 was isolated from only one oyster sample. Strong linear correlations betweenV. cholerae and temperature, salinity, or the other physical/chemical parameters measured,Escherichia coli, or fecal coliforms were not observed, but a range of temperatures and salinities appeared relevant to the distribution of the organism. The organism was present in the highest concentrations when salinities were 10‰-25‰ and temperatures were 20‡C-35‡C.In vitro growth curves of 95V. cholerae environmental isolates further supported that 10‰-25‰ was an ideal salinity range for the organisms. The results suggest thatV. cholerae is a widely distributed organism in the nutrient-rich warm waters of the Gulf Coast estuaries.

  17. Effects of Pollution on Vibrios in Woji River | Ojesanmi | Journal of ...

    African Journals Online (AJOL)

    The effect of pollution on Vibrio spp. in five sampling stations along Woji River in Port Harcourt was studied in the months of April and November 2010. Vibrio vulnificus, V. parahaemolyticus and V. alginolyticus were isolated. The Plate count technique on Thiosulphate Citrate Bile Salt agar revealed a high population density ...

  18. Efek Antibakteri Ekstrak Daun Mimba (Azadirachta indica A. Juss terhadap Bakteri Vibrio algynoliticus Secara In Vitro

    Directory of Open Access Journals (Sweden)

    Uli Ayini

    2014-03-01

    Full Text Available Budidaya udang windu di Indonesia telah berkembang pesat. Salah satu kendala budidaya udang adalah penyakit Vibriosis yang disebabkan oleh bakteri Vibrio algynoliticus. Tujuan penelitian ini adalah untuk mengetahui efek antibakeri ekstrak daun mimba terhadap bakteri Vibrio algynoliticus. Penelitian ini menggunakan metode dilusi untuk mengetahui efek antibakteri ekstrak daun mimba terhadap bakteri Vibrio algynoliticus secara in vitro. Konsentrasi ekstrak yang digunakan (% yaitu: 0; 2,5; 5; 7,5; 10; 12,5 dan sebagai kontrol terdiri dari kontrol positif, dan kontrol negatif. Pengumpulan data untuk menentukan MIC (Minimum Inhibitory Concentration dilakukan dengan membandingkan kejernihan kultur di medium TSB 2% pada berbagai konsentrasi yang berbeda, dengan kontrol positif dan kontrol negatif. Penentuan MBC (Minimum Bacterisidal Concentration dilakukan dengan melihat ada tidaknya dan jumlah koloni bakteri Vibrio alginolyticus yang muncul pada medium subkultur TSA 2% setelah inkubasi 24 jam. Hasil penelitian menunjukkan nilai MIC yaitu konsentrasi 5%, hal ini ditunjukkan dengan tabung yang mulai jernih. Nilai MBC ekstrak daun mimba terhadap bakteri Vibrio alginolyticus adalah konsentrasi 12,5% ditandai dengan sudah tidak munculnya  koloni bakteri Vibrio alginolyticus. Berdasarkan penelitian ini dapat disimpulkan bahwa ekstrak daun mimba dapat memberikan efek antibakteri terhadap bakteri Vibrio alginolyticus secara in vitro.Tiger shrimp cultivation in Indonesia has been growing rapidly. The main obstacle is the shrimp farming vibriosis disease caused by the bacterium Vibrio algynoliticus. The aim of this research was to determine the effects of neem leaf extract antibakeri against Vibrio algynoliticus. This study used a dilution method to determine the antibacterial effect of neem leaf extract against Vibrio algynoliticus bacteria in vitro. The concentration of the extract used (%: 0; 2.5; 5; 7.5; 10; 12.5 and as a control consisting of a positive

  19. Response of Vibrio cholerae to Low-Temperature Shifts: CspV Regulation of Type VI Secretion, Biofilm Formation, and Association with Zooplankton.

    Science.gov (United States)

    Townsley, Loni; Sison Mangus, Marilou P; Mehic, Sanjin; Yildiz, Fitnat H

    2016-07-15

    The ability to sense and adapt to temperature fluctuation is critical to the aquatic survival, transmission, and infectivity of Vibrio cholerae, the causative agent of the disease cholera. Little information is available on the physiological changes that occur when V. cholerae experiences temperature shifts. The genome-wide transcriptional profile of V. cholerae upon a shift in human body temperature (37°C) to lower temperatures, 15°C and 25°C, which mimic those found in the aquatic environment, was determined. Differentially expressed genes included those involved in the cold shock response, biofilm formation, type VI secretion, and virulence. Analysis of a mutant lacking the cold shock gene cspV, which was upregulated >50-fold upon a low-temperature shift, revealed that it regulates genes involved in biofilm formation and type VI secretion. CspV controls biofilm formation through modulation of the second messenger cyclic diguanylate and regulates type VI-mediated interspecies killing in a temperature-dependent manner. Furthermore, a strain lacking cspV had significant defects for attachment and type VI-mediated killing on the surface of the aquatic crustacean Daphnia magna Collectively, these studies reveal that cspV is a major regulator of the temperature downshift response and plays an important role in controlling cellular processes crucial to the infectious cycle of V. cholerae Little is known about how human pathogens respond and adapt to ever-changing parameters of natural habitats outside the human host and how environmental adaptation alters dissemination. Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, experiences fluctuations in temperature in its natural aquatic habitats and during the infection process. Furthermore, temperature is a critical environmental signal governing the occurrence of V. cholerae and cholera outbreaks. In this study, we showed that V. cholerae reprograms its transcriptome in response to

  20. [Environmental drivers of emergence and spreading of Vibrio epidemics in South America].

    Science.gov (United States)

    Gavilán, Ronnie G; Martínez-Urtaza, Jaime

    2011-03-01

    Vibrio cholerae and V. parahaemolyticus are the two Vibrio species with a major impact on human health. Diseases caused by both pathogens are acquiring increasing relevance due to their expansion at global scale. In this paper, we resume the ecological aspects associated with the arrival and spreading of infections caused by V. parahaemolyticus and V. cholerae in Peru from a South American perspective. Moreover, we discuss the similarities in the emergence in Peru of cholera cases in 1991 and V. parahaemolyticus infections in 1997. These constituted exceptional experiments to evaluate the relationships between the Vibrio epidemics and changes in the environment. The epidemic radiations of V. cholerae and V. parahaemolyticus constitute to clear examples supporting the oceanic dispersion of pathogenic vibrios and have enabled the identification of El Niño events as a potential mechanism for the spreading of diseases through the ocean.

  1. Transcription patterns of genes encoding four metallothionein homologs in Daphnia pulex exposed to copper and cadmium are time- and homolog-dependent

    International Nuclear Information System (INIS)

    Asselman, Jana; Shaw, Joseph R.; Glaholt, Stephen P.; Colbourne, John K.; De Schamphelaere, Karel A.C.

    2013-01-01

    Highlights: •Transcription patterns of 4 metallothionein isoforms in Daphnia pulex. •Under cadmium and copper stress these patterns are time-dependent. •Under cadmium and copper stress these patterns are homolog-dependent. •The results stress the complex regulation of metallothioneins. -- Abstract: Metallothioneins are proteins that play an essential role in metal homeostasis and detoxification in nearly all organisms studied to date. Yet discrepancies between outcomes of chronic and acute exposure experiments hamper the understanding of the regulatory mechanisms of their isoforms following metal exposure. Here, we investigated transcriptional differences among four identified homologs (mt1–mt4) in Daphnia pulex exposed across time to copper and cadmium relative to a control. Transcriptional upregulation of mt1 and mt3 was detected on day four following exposure to cadmium, whereas that of mt2 and mt4 was detected on day two and day eight following exposure to copper. These results confirm temporal and metal-specific differences in the transcriptional induction of genes encoding metallothionein homologs upon metal exposure which should be considered in ecotoxicological monitoring programs of metal-contaminated water bodies. Indeed, the mRNA expression patterns observed here illustrate the complex regulatory system associated with metallothioneins, as these patterns are not only dependent on the metal, but also on exposure time and the homolog studied. Further phylogenetic analysis and analysis of regulatory elements in upstream promoter regions revealed a high degree of similarity between metallothionein genes of Daphnia pulex and Daphnia magna, a species belonging to the same genus. These findings, combined with a limited amount of available expression data for D. magna metallothionein genes, tentatively suggest a potential generalization of the metallothionein response system between these Daphnia species

  2. Transcription patterns of genes encoding four metallothionein homologs in Daphnia pulex exposed to copper and cadmium are time- and homolog-dependent

    Energy Technology Data Exchange (ETDEWEB)

    Asselman, Jana, E-mail: jana.asselman@ugent.be [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, Ghent (Belgium); Shaw, Joseph R.; Glaholt, Stephen P. [The School of Public and Environmental Affairs, Indiana University, Bloomington, IN (United States); Colbourne, John K. [School of Biosciences, The University of Birmingham, Birmingham (United Kingdom); De Schamphelaere, Karel A.C. [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, Ghent (Belgium)

    2013-10-15

    Highlights: •Transcription patterns of 4 metallothionein isoforms in Daphnia pulex. •Under cadmium and copper stress these patterns are time-dependent. •Under cadmium and copper stress these patterns are homolog-dependent. •The results stress the complex regulation of metallothioneins. -- Abstract: Metallothioneins are proteins that play an essential role in metal homeostasis and detoxification in nearly all organisms studied to date. Yet discrepancies between outcomes of chronic and acute exposure experiments hamper the understanding of the regulatory mechanisms of their isoforms following metal exposure. Here, we investigated transcriptional differences among four identified homologs (mt1–mt4) in Daphnia pulex exposed across time to copper and cadmium relative to a control. Transcriptional upregulation of mt1 and mt3 was detected on day four following exposure to cadmium, whereas that of mt2 and mt4 was detected on day two and day eight following exposure to copper. These results confirm temporal and metal-specific differences in the transcriptional induction of genes encoding metallothionein homologs upon metal exposure which should be considered in ecotoxicological monitoring programs of metal-contaminated water bodies. Indeed, the mRNA expression patterns observed here illustrate the complex regulatory system associated with metallothioneins, as these patterns are not only dependent on the metal, but also on exposure time and the homolog studied. Further phylogenetic analysis and analysis of regulatory elements in upstream promoter regions revealed a high degree of similarity between metallothionein genes of Daphnia pulex and Daphnia magna, a species belonging to the same genus. These findings, combined with a limited amount of available expression data for D. magna metallothionein genes, tentatively suggest a potential generalization of the metallothionein response system between these Daphnia species.

  3. Morphology and ecology of Daphnia middendorffiana, Fisher 1851 (Crustacea, Daphniidae from four new populations in the Alps

    Directory of Open Access Journals (Sweden)

    Rocco TIBERTI

    2011-08-01

    Full Text Available Daphnia middendorffiana has an arctic, circumpolar distribution, with some isolated southerly populations restricted to mountainous areas, including the Alps. In this paper, new records of Daphnia middendorffiana on the Alps are reported. The species was regularly recorded in several samples collected from 2006 to 2009 in four high altitude lakes in the Gran Paradiso National Park (GPNP during the ice free period. This is the third finding for the Alps and the described populations are the largest. Chemical and morphometric features of the lakes are provided, the morphology of the Daphnia middendorffiana from GPNP is described as well as some aspects concerning its ecology. The studied lakes are small, oligotrophic (total phosphorus ranged from 0 to 7 μg L-1 and well preserved from acidification risk (pH ranged from 6.45 to 8.14. D. middendorffiana is the largest zooplanktonic crustacean inhabiting the Alpine lakes in GPNP reaching 3.43 mm in length; the morphological analysis noted some differences within the studied populations; however there is a clear resemblance to the only Alpine population previously described (from Central Alps, Bognanco Valley, Lake Campo IV and to the arctic populations. D. middendorffiana in GPNP lives at low density levels, reaching higher densities in late August and early September. No males have been found during the sample campaign confirming its ability to produce asexual viable diapauses eggs. This study confirms the attitude of this species for cold and oligotrophic waters and increases the current knowledge on the geographical distribution, morphology and ecology of this species in Alpine environments. The finding of D. middendordorffiana in the GPNP poses interesting issues concerning the phylogeography of Alpine Daphnia middendorffiana, as well as raising need for conservation efforts aimed at keeping the populations safe from several global and local threats, such as climate warming and the ecological

  4. Multiple enzymatic profiles of Vibrio parahaemolyticus strains isolated from oysters

    Directory of Open Access Journals (Sweden)

    Renata Albuquerque Costa

    Full Text Available The enzymatic characterization of vibrios has been used as a virulence indicator of sanitary interest. The objective of this study was to determine the enzymatic profile of Vibrio parahaemolyticus strains (n = 70 isolated from Crassostrea rhizophorae oysters. The strains were examined for the presence of gelatinase (GEL, caseinase (CAS, elastase (ELAS, phospholipase (PHOS, lipase (LIP, amilase (AML and DNase. All enzymes, except elastase, were detected in more than 60% of the strains. The most recurrent enzymatic profiles were AML + DNase + PHOS + GEL + LIP (n = 16; 22.9% and AML + CAS + DNase + PHOS + GEL + LIP (n = 21; 30%. Considering the fact that exoenzyme production by vibrios is closely related to virulence, one must be aware of the bacteriological risk posed to human health by the consumption of raw or undercooked oysters.

  5. Relationships between environmental factors and pathogenic Vibrios in the Northern Gulf of Mexico.

    Science.gov (United States)

    Johnson, C N; Flowers, A R; Noriea, N F; Zimmerman, A M; Bowers, J C; DePaola, A; Grimes, D J

    2010-11-01

    Although autochthonous vibrio densities are known to be influenced by water temperature and salinity, little is understood about other environmental factors associated with their abundance and distribution. Densities of culturable Vibrio vulnificus containing vvh (V. vulnificus hemolysin gene) and V. parahaemolyticus containing tlh (thermolabile hemolysin gene, ubiquitous in V. parahaemolyticus), tdh (thermostable direct hemolysin gene, V. parahaemolyticus pathogenicity factor), and trh (tdh-related hemolysin gene, V. parahaemolyticus pathogenicity factor) were measured in coastal waters of Mississippi and Alabama. Over a 19-month sampling period, vibrio densities in water, oysters, and sediment varied significantly with sea surface temperature (SST). On average, tdh-to-tlh ratios were significantly higher than trh-to-tlh ratios in water and oysters but not in sediment. Although tlh densities were lower than vvh densities in water and in oysters, the opposite was true in sediment. Regression analysis indicated that SST had a significant association with vvh and tlh densities in water and oysters, while salinity was significantly related to vibrio densities in the water column. Chlorophyll a levels in the water were correlated significantly with vvh in sediment and oysters and with pathogenic V. parahaemolyticus (tdh and trh) in the water column. Furthermore, turbidity was a significant predictor of V. parahaemolyticus density in all sample types (water, oyster, and sediment), and its role in predicting the risk of V. parahaemolyticus illness may be more important than previously realized. This study identified (i) culturable vibrios in winter sediment samples, (ii) niche-based differences in the abundance of vibrios, and (iii) predictive signatures resulting from correlations between environmental parameters and vibrio densities.

  6. Trophic transfer of gold nanoparticles from Euglena gracilis or Chlamydomonas reinhardtii to Daphnia magna

    International Nuclear Information System (INIS)

    Lee, Woo-Mi; Yoon, Sung-Ji; Shin, Yu-Jin; An, Youn-Joo

    2015-01-01

    Understanding the trophic transfer of nanoparticles (NPs) is important because NPs are small enough to easily penetrate into organisms. In this study, we evaluated the trophic transfer of gold NPs (AuNPs) within the aquatic food chain. We observed AuNPs transfer from 2 species of primary producers (Chlamydomonas reinhardtii or Euglena gracilis) to the primary consumer (Daphnia magna). Also, bioaccumulation of AuNPs in E. gracilis was higher than that in C. reinhardtii. The reasons for the difference in Au accumulation may be the physical structure of these organisms, and the surface area that is available for interaction with NPs. C. reinhardtii has a cell wall that may act as a barrier to the penetration of NPs. The size of E. gracilis is larger than that of C. reinhardtii. This study demonstrates the trophic transfer of AuNPs from a general producer to a consumer in an aquatic environment. - Highlights: • This study evaluated the trophic transfer of AuNPs in an aquatic food chain. • Chlamydomonas reinhardtii and Euglena gracilis were selected as the primary producers. • Daphnia magna was used as the primary consumer. • The bioaccumulation of AuNPs in E. gracilis was higher than that in C. reinhardtii. • AuNPs were transferred from C. reinhardtii and E. gracilis to D. magna. - Gold nanoparticles can transfer from primary producers (Chlamydomonas reinhardtii or Euglena gracilis) to the primary consumer (Daphnia magna) in an aquatic environment

  7. Negative effects of UVB-irradiated phytoplankton on life history traits and fitness of Daphnia magna

    NARCIS (Netherlands)

    Lange, de H.J.; Reeuwijk, van P.L.

    2003-01-01

    1. We tested the effect of ultraviolet-B (UVB)-irradiated phytoplankton on life history characteristics of Daphnia magna . Two phytoplankton species were used, Chlamydomonas reinhardtii and Cryptomonas pyrenoidifera . The phytoplankton species were cultured under photosynthetically active radiation

  8. Sensitivity of Vibrio cholerae cells to lethal and mutagenic effect of UV-irradiation mediated by plasmids

    International Nuclear Information System (INIS)

    Tiganova, I.G.; Evdokimova, N.M.; Aleshkin, G.I.

    1988-01-01

    The effect of UV-irradiation on Vibrio cholerae cells and its changes mediated by the plasmid R245 have been studied. Vibrio cholerae strains 569B and RV31 have been shown to be considerably more sensitive to lethal effect of UV-irradiation as compared with Escherichia coli and Salmonella typhimurium cells. Highly toxigenic strain 569B and practically atoxigenic strain RV31 have the same UV-sensitivity. Lethla effect of UV-irradiation on Vibrio cholerae cells is incresed when the irradiated cells are plated on enriched media. UV-induction of mutations was not registered in plasmidless strains of Vibrio cholerae. Plasmid R245 increase UV-resistance of vibrio cells and makes them UV-mutable

  9. Is the evaluation of "traditional" physicochemical parameters sufficient to explain the potential toxicity of the treated wastewater at sewage treatment plants?

    Science.gov (United States)

    Vasquez, M I; Fatta-Kassinos, D

    2013-06-01

    Water scarcity is one of the most important environmental and public health problems of our century. Treated wastewater reuse seems to be the most attractive option for the enhancement of water resources. However, the lack of uniform guidelines at European and/or Mediterranean level leaves room for application of varying guidelines and regulations, usually not based on risk assessment towards humans and the environment. The benefits of complementing the physicochemical evaluation of wastewater with a biological one are demonstrated in the present study using Cyprus, a country with extended water reuse applications, as an example. Four organisms from different trophic levels were used for the biological assessment of the wastewater, namely, Pseudokirchneriella subcapitata, Daphnia magna, Artemia salina and Vibrio fischeri. The physicochemical assessment of wastewater based on "traditional" chemical parameters indicated that the quality of the wastewater complies with the limits set by the relevant national guidelines for disposal. The ecotoxicological assessment, however, indicated the presence of toxicity throughout the sampling periods and most importantly an increase of the toxicity of the treated wastewater during summer compared to winter. The resulting poor correlation between the physicochemical and biological assessments demonstrates that the two assessments are necessary and should be performed in parallel in order to be able to obtain concrete results on the overall quality of the treated effluent. Moreover, a hazard classification scheme for wastewater is proposed, which can enable the comparison of the data sets of the various parameters deriving from the biological assessment in a comprehensive way.

  10. Fate and transformation products of amine-terminated PAMAM dendrimers under ozonation and irradiation

    International Nuclear Information System (INIS)

    Santiago-Morales, Javier; Rosal, Roberto; Hernando, María D.; Ulaszewska, Maria M.; García-Calvo, Eloy; Fernández-Alba, Amadeo R.

    2014-01-01

    Highlights: • We detected transformation products from dendrimer under ozonation and irradiation. • Retro-Michael fragmentation pathway with highly oxygenated structures. • High toxicity of G3 PAMAM dendrimer for green algae. • Reactive oxygen species were associated with the toxic damage. • Transformation mixtures could be more toxic than the parent dendrimer. -- Abstract: This article deals with the degradation of a third-generation (G3) poly(amidoamine) (PAMAM) dendrimer under ozonation and irradiation. The identification and quantification of G3 PAMAM dendrimer and its transformation products has been performed by liquid chromatography–electrospray ionization-hybrid quadrupole time-of-flight-mass spectrometry. The dendrimer was completely depleted by ozone in less than 1 min. The effect of ultraviolet irradiation was attributed to hydroxyl-mediated oxidation. The transformation products were attributed to the oxidation of amines, which resulted in highly oxidized structures with abundance of carboxylic acids, which started from the formation of amine oxide and the scission of the C-N bond of the amide group. We studied the toxicity of treated mixtures for six different organisms: the acute toxicity for the bacterium Vibrio fischeri and the microcrustacean Daphnia magna, the multigenerational growth inhibition of the alga Pseudokirchneriella subcapitata, and the seed germination phytotoxicity of Licopersicon esculentum, Lactuca sativa and Lolium perenne. Ozonation and irradiation originated transformation products are more toxic than the parent dendrimer. The toxicity of the dendrimer for the green alga was linked to a strong increase of intracellular reactive oxygen species with intense lipid peroxidation

  11. Fate and transformation products of amine-terminated PAMAM dendrimers under ozonation and irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Santiago-Morales, Javier [Department of Chemical Engineering, University of Alcalá, 28871 Alcalá de Henares, Madrid (Spain); Rosal, Roberto, E-mail: roberto.rosal@uah.es [Department of Chemical Engineering, University of Alcalá, 28871 Alcalá de Henares, Madrid (Spain); Advanced Study Institute of Madrid, IMDEA Agua, Parque Científico Tecnológico, 28805 Alcalá de Henares, Madrid (Spain); Hernando, María D. [Spanish National Institute for Agricultural and Food Research and Technology – INIA, Crta. de la Coruña, km 7.5, 28040 Madrid (Spain); Ulaszewska, Maria M. [Advanced Study Institute of Madrid, IMDEA Agua, Parque Científico Tecnológico, 28805 Alcalá de Henares, Madrid (Spain); García-Calvo, Eloy [Department of Chemical Engineering, University of Alcalá, 28871 Alcalá de Henares, Madrid (Spain); Advanced Study Institute of Madrid, IMDEA Agua, Parque Científico Tecnológico, 28805 Alcalá de Henares, Madrid (Spain); Fernández-Alba, Amadeo R. [Advanced Study Institute of Madrid, IMDEA Agua, Parque Científico Tecnológico, 28805 Alcalá de Henares, Madrid (Spain); Pesticide Residue Research Group, Department of Hydrogeology and Analytical Chemistry, University of Almería, 04120 Almería (Spain)

    2014-02-15

    Highlights: • We detected transformation products from dendrimer under ozonation and irradiation. • Retro-Michael fragmentation pathway with highly oxygenated structures. • High toxicity of G3 PAMAM dendrimer for green algae. • Reactive oxygen species were associated with the toxic damage. • Transformation mixtures could be more toxic than the parent dendrimer. -- Abstract: This article deals with the degradation of a third-generation (G3) poly(amidoamine) (PAMAM) dendrimer under ozonation and irradiation. The identification and quantification of G3 PAMAM dendrimer and its transformation products has been performed by liquid chromatography–electrospray ionization-hybrid quadrupole time-of-flight-mass spectrometry. The dendrimer was completely depleted by ozone in less than 1 min. The effect of ultraviolet irradiation was attributed to hydroxyl-mediated oxidation. The transformation products were attributed to the oxidation of amines, which resulted in highly oxidized structures with abundance of carboxylic acids, which started from the formation of amine oxide and the scission of the C-N bond of the amide group. We studied the toxicity of treated mixtures for six different organisms: the acute toxicity for the bacterium Vibrio fischeri and the microcrustacean Daphnia magna, the multigenerational growth inhibition of the alga Pseudokirchneriella subcapitata, and the seed germination phytotoxicity of Licopersicon esculentum, Lactuca sativa and Lolium perenne. Ozonation and irradiation originated transformation products are more toxic than the parent dendrimer. The toxicity of the dendrimer for the green alga was linked to a strong increase of intracellular reactive oxygen species with intense lipid peroxidation.

  12. Vibrios on the half shell: what the walrus and the carpenter didn't know.

    Science.gov (United States)

    Blake, P A

    1983-10-01

    At least nine Vibrio species have been associated with disease in the United States. Vibrio fluvialis, V. hollisae, V. mimicus, and V. parahaemolyticus cause diarrheal diseases, but may also be encountered in extraintestinal infections such as wound and ear infections, septicemia, and cholecystitis. Vibrio alginolyticus, V. damsela, V. metschnikovii, and V. vulnificus primarily cause extraintestinal disease. Toxigenic V. cholerae O1 is the cause of epidemic cholera, whereas nontoxigenic V. cholerae O1 and non-O1 V. cholerae have been associated with both diarrheal and extraintestinal diseases. Most reports of vibrio infections have come from states along the Atlantic Ocean and Gulf of Mexico and from Hawaii, and most of the infections have occurred during summer and fall. Wound and ear infections have occurred after exposure to salty or brackish water or to drippings from raw seafoods. Foodborne vibrio infections are almost all caused by seafoods, especially oysters eaten raw. Thorough cooking and careful handling will render seafoods safe for consumption.

  13. What Can Molecular Markers Tell Us About the Evolutionary History of Daphnia Species Complexes

    NARCIS (Netherlands)

    Schwenk, K.; Ender, A.; Streit, B.

    1995-01-01

    Despite the wealth of information on the ecology of Daphnia species, the systematics and phylogeny of the genus is still unresolved. The taxonomic uncertainties are based in part on the phenomenon of interspecific hybridization, which has been well documented for species of the D.

  14. Culture of Daphnia sp. (crustacean – cladocera): the effect of manure variation on the growth, natality, and mortality

    Science.gov (United States)

    Herman, H.; Andriani, Y.; Sahidin, A.; Hidayat, T.; Herawati, T.

    2018-04-01

    The objective of this research was to analyze the growth rate, reproduction rate, and mortality rate of Daphnia sp. which cultured in variant organic manure. This research used experimental method Randomized Completely Block Design (RCBD) with four treatment and three replications. The treatments in this research were the variant manures from chicken, quail, goat, and cow with same of growth (2,4 g/l). Daphnia cultured with using 100 breeders since from neonets (0 day) until growth up and died in one life cycle. At the 3-days, culture of Daphnia sp was give peak population with maximum age of culture using quail manure is 7 days, and other treatments are 8 days. The growth rate and the reproduction rate of using quail manure was higher than using chicken manure, goat manure, and cow manure (mean GR = 3.68 : 2.32 : 2.74 : 2.97; mean RR = 3.87 : 2.59 : 3.00 : 3.31; p culture, quail manure give the lowest of mortality rate than using chicken manure, goat manure, and cow manure (mean MR = 0.19 : 0.28 : 0.26 : 0.34).

  15. Genomic diversity of vibrios associated with the Brazilian coral Mussismilia hispida and its sympatric zoanthids (Palythoa caribaeorum, Palythoa variabilis and Zoanthus solanderi).

    Science.gov (United States)

    Chimetto, L A; Brocchi, M; Gondo, M; Thompson, C C; Gomez-Gil, B; Thompson, F L

    2009-06-01

    A taxonomic survey of the vibrios associated with the Brazilian endemic coral Mussismilia hispida and the sympatric zoanthids (i.e. Palythoa caribaeorum, Palythoa variabilis and Zoanthus solanderi). Mucus of 54 cnidarian specimens collected in three different places at São Sebastião in two consecutive years (i.e. 2005 and 2006) was used for taxonomic characterization of the cnidarian microbiota. Ninety-eight of the 151 vibrio isolates fell within the vibrio core group according to partial 16S rDNA sequences. We performed the sequencing of recA and pyrH genes of all vibrio isolates. The most abundant taxa belonged to the vibrio core group (Vibrio harveyi, Vibrio rotiferianus, Vibrio campbellii and Vibrio alginolyticus), Vibrio mediterranei (=Vibrio shillonii) and Vibrio chagasii. With the exception of V. chagasii which was found only in the mucus of M. hispida, the other species appeared in different hosts with no evidence for the presence of host-specific clones or species. Using rep-PCR analysis, we observed a high genomic heterogeneity within the vibrios. Each vibrio isolate generated a different rep-PCR fingerprint pattern. There was a complete agreement between the grouping based on rep-PCR and concatenated sequences of pyrH, recA and 16S rDNA, but the pyrH gene has the highest discriminatory power for vibrio species identification. The vibrio core group is dominant in the mucus of these cnidarians. There is a tremendous diversity of vibrio lineages within the coral mucus. pyrH gene sequences permit a clear-cut identification of vibrios. The taxonomic resolution provided by pyrH (but not recA) appears to be enough for identifying species of vibrios and for disclosing putative new taxa. The vibrio core group appears to be dominant in the mucus of the Brazilian cnidarians. The overrepresentation of these vibrios may reflect as yet unknown ecological functions in the coral holobiont.

  16. Evaluation of the Treatment Process of Landfill Leachate Using the Toxicity Assessment Method

    Directory of Open Access Journals (Sweden)

    Aifeng Qiu

    2016-12-01

    Full Text Available Landfill leachate is composed of a complex composition with strong biological toxicity. The combined treatment process of coagulation and sedimentation, anaerobics, electrolysis, and aerobics was set up to treat landfill leachate. This paper explores the effect of different operational parameters of coagulation and sedimentation tanks and electrolytic cells, while investigating the combined process for the removal efficiency of physicochemical indices after processing the landfill leachate. Meanwhile, a battery of toxicity tests with Vibrio fischeri, zebrafish larvae, and embryos were conducted to evaluate acute toxicity and calculated the toxicity reduction efficiency after each treatment process. The combined treatment process resulted in a 100% removal efficiency of Cu, Cd and Zn, and a 93.50% and an 87.44% removal efficiency of Ni and Cr, respectively. The overall removal efficiency of chemical oxygen demand (COD, ammonium nitrogen (NH4+-N, and total nitrogen (TN were 93.57%, 97.46% and 73.60%, respectively. In addition, toxicity test results showed that the acute toxicity of landfill leachate had also been reduced significantly: toxicity units (TU decreased from 84.75 to 12.00 for zebrafish larvae, from 82.64 to 10.55 for zebrafish embryos, and from 3.41 to 0.63 for Vibrio fischeri. The combined treatment process was proved to be an efficient treatment method to remove heavy metals, COD, NH4+-N, and acute bio-toxicity of landfill leachate.

  17. Evaluation of the Treatment Process of Landfill Leachate Using the Toxicity Assessment Method.

    Science.gov (United States)

    Qiu, Aifeng; Cai, Qiang; Zhao, Yuan; Guo, Yingqing; Zhao, Liqian

    2016-12-21

    Landfill leachate is composed of a complex composition with strong biological toxicity. The combined treatment process of coagulation and sedimentation, anaerobics, electrolysis, and aerobics was set up to treat landfill leachate. This paper explores the effect of different operational parameters of coagulation and sedimentation tanks and electrolytic cells, while investigating the combined process for the removal efficiency of physicochemical indices after processing the landfill leachate. Meanwhile, a battery of toxicity tests with Vibrio fischeri , zebrafish larvae, and embryos were conducted to evaluate acute toxicity and calculated the toxicity reduction efficiency after each treatment process. The combined treatment process resulted in a 100% removal efficiency of Cu, Cd and Zn, and a 93.50% and an 87.44% removal efficiency of Ni and Cr, respectively. The overall removal efficiency of chemical oxygen demand (COD), ammonium nitrogen (NH₄⁺-N), and total nitrogen (TN) were 93.57%, 97.46% and 73.60%, respectively. In addition, toxicity test results showed that the acute toxicity of landfill leachate had also been reduced significantly: toxicity units (TU) decreased from 84.75 to 12.00 for zebrafish larvae, from 82.64 to 10.55 for zebrafish embryos, and from 3.41 to 0.63 for Vibrio fischeri . The combined treatment process was proved to be an efficient treatment method to remove heavy metals, COD, NH₄⁺-N, and acute bio-toxicity of landfill leachate.

  18. Lutzomyia (Pintomyia) fischeri (Diptera: Psychodidae: Phlebotominae), a probable vector of American cutaneous leishmaniasis: detection of natural infection by Leishmania (Viannia) DNA in specimens from the municipality of Porto Alegre (RS), Brazil, using multiplex PCR assay.

    Science.gov (United States)

    Pita-Pereira, Daniela de; Souza, Getúlio D; Pereira, Thaís de Araújo; Zwetsch, Adriana; Britto, Constança; Rangel, Elizabeth F

    2011-12-01

    In order to determine natural Leishmania (Viannia) infection in Lutzomyia (Pintomyia) fischeri, a multiplex PCR methodology coupled to non-isotopic hybridization was adopted for the analysis of sand fly samples collected by CDC light traps in an endemic area of American Cutaneous Leishmaniasis (ACL) in the periurban region of the municipality of Porto Alegre, Rio Grande do Sul State, Brazil. We analyzed by PCR methodology 560 specimens of Lutzomyia (Pintomyia) fischeri (520 females and 40 males). The wild sand flies were grouped into 56 pools (52 females and 4 males) of 10 each, and positive results were detected in 2 of the 52 female pools, representing a minimum infection rate of 0.38% based on the presence of at least 1 infected insect in the pool. This result associated with some local evidence such as anthopophily, spatial distribution in accordance with the transmission area and human case incidence, suggests that L. (P.)fischeri may be considered as a secondary vector of ACL in the studied locality. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Investigation of Vibrio alginolyticus, V. harveyi, and V. parahaemolyticus in large yellow croaker, Pseudosciaena crocea (Richardson reared in Xiangshan Bay, China

    Directory of Open Access Journals (Sweden)

    Lu Liu

    2016-05-01

    Full Text Available Large yellow croaker (LYC, Pseudosciaena crocea is an economically important fish species of mariculture in China. The variation of yearly production of LYC has been increasingly related to the outbreaks of fish diseases. Moreover, Vibrio infections have been identified in this fish frequently. To understand the pattern of Vibrio infections in LYC, we conducted a culture-independent survey of Vibrios in farmed LYC populations using a multiplex PCR method targeting Vibrio alginolyticus, Vibrio harveyi and Vibrio parahaemolyticus. The results showed that three fish pathogenic Vibrios had been detected in LYC populations at each sampling with a prevalence ranging from 6.7% to 73.3% but no single species dominated the Vibrio infection. The findings indicate that three Vibrio species still have impact on health status of farmed LYC and LYC aquaculture requires more efficacious prophylactic strategies. Keywords: Vibrio, Large yellow croaker, Multiplex PCR, Epidemiology

  20. Food quantity affects the sensitivity of Daphnia to road salt.

    Science.gov (United States)

    Brown, Arran H; Yan, Norman D

    2015-04-07

    Road deicing operations have raised chloride (Cl) levels in many temperate lakes in Europe and North America. These lakes vary widely in trophic status, but to date, no one has quantified the interaction between food quantity and road salt toxicity. We examined the effects of food quantity (particulate algal C concentration (C)) on the chronic toxicity of Cl to Daphnia in soft-water bioassays. There was a strong positive linear relationship (r(2) = 0.92 for NaCl and r(2) = 0.96 for CaCl2) between food quantity and Cl LC50. As food quantity increased from 0.2 to 1.0 mg C/L (levels characteristic of oligotrophic to eutrophic lakes, respectively), the chronic Cl LC50 increased from 55.7 to 284.8 mg Cl/L. Salt type (NaCl or CaCl2) did not affect the Cl LC50, Daphnia life history parameters, or the intrinsic rate of population increase (r). The life history parameter most sensitive to Cl was neonate production. Cl did not inhibit egg production, nor was the maternal lipid investment in eggs changed, but egg viability and the subsequent release of live neonates decreased as Cl levels increased and food decreased. Our results suggest the trophic status of lakes should be considered when assessing ecological threat from Cl.

  1. A small diffusible signal molecule is responsible for the global control of virulence and exoenzyme production in the plant pathogen Erwinia carotovora.

    Science.gov (United States)

    Pirhonen, M; Flego, D; Heikinheimo, R; Palva, E T

    1993-06-01

    Virulence of the plant pathogen Erwinia carotovora subsp. carotovora is dependent on the production and secretion of a complex arsenal of plant cell wall-degrading enzymes. Production of these exoenzymes is controlled by a global regulatory mechanism. A virulent mutants in one of the regulatory loci, expI, show a pleiotropic defect in the growth phase-dependent transcriptional activation of exoenzyme gene expression. The expI gene encodes a 26 kDa polypeptide that is structurally and functionally related to the luxI gene product of Vibrio fischeri. Functional similarity of expI and luxI has been demonstrated by reciprocal genetic complementation experiments. LuxI controls bioluminescence in V.fischeri in a growth phase-dependent manner by directing the synthesis of the diffusible autoinducer, N-(3-oxohexanoyl) homoserine lactone. E.c. subsp. carotovora expI+ strains or Escherichia coli harboring the cloned expI gene excrete a small diffusible signal molecule that complements the expI mutation of Erwinia as well as a luxI mutation of V.fischeri. This extracellular complementation can also be achieved by E.coli harboring the luxI gene from V.fischeri or by adding the synthetic V.fischeri autoinducer. Both the production of the plant tissue-macerating exoenzymes and the ability of the bacteria to propagate in planta are restored in expI mutants by autoinducer addition. These data suggest that the same signal molecule is employed in control of such diverse processes as virulence in a plant pathogen and bioluminescence in a marine bacterium, and may represent a general mechanism by which bacteria modulate gene expression in response to changing environmental conditions.

  2. What goes down must come up: symmetry in light-induced migration behaviour of Daphnia

    NARCIS (Netherlands)

    Van Gool, E.; Ringelberg, J.

    2003-01-01

    During a short period of the year, Daphnia may perform a phenotypically induced diel vertical migration. For this to happen, light-induced swimming reactions must be enhanced both at dawn and at dusk. Enhanced swimming in response to light intensity increase can be elicited by fish-associated

  3. Context-dependent individual behavioral consistency in Daphnia

    DEFF Research Database (Denmark)

    Heuschele, Jan; Ekvall, Mikael T.; Bianco, Giuseppe

    2017-01-01

    The understanding of consistent individual differences in behavior, often termed "personality," for adapting and coping with threats and novel environmental conditions has advanced considerably during the last decade. However, advancements are almost exclusively associated with higher-order animals......, whereas studies focusing on smaller aquatic organisms are still rare. Here, we show individual differences in the swimming behavior of Daphnia magna, a clonal freshwater invertebrate, before, during, and after being exposed to a lethal threat, ultraviolet radiation (UVR). We show consistency in swimming...... that of adults. Overall, we show that aquatic invertebrates are far from being identical robots, but instead they show considerable individual differences in behavior that can be attributed to both ontogenetic development and individual consistency. Our study also demonstrates, for the first time...

  4. Colony formation in Scenedesmus: no contribution of urea in induction by a lipophilic Daphnia exudate

    NARCIS (Netherlands)

    Lürling, M.; Von Elert, E.

    2001-01-01

    The common green alga Scenedesmus may respond morphologically to numerous environmental factors. The formation of colonies in Scenedesmus resulting from exposure to grazer (Daphnia) excreta is of particular interest since the induced colony formation may be an induced defense. Recent studies

  5. Characterization of Vibrio species isolated from freshwater fishes by ribotyping

    OpenAIRE

    Mishra, P.; Samanta, M.; Mohanty, S.; Maiti, N. K.

    2010-01-01

    Three Vibrio species from the resident microflora of gastrointestinal tract of freshwater carps and prawns were isolated and confirmed biochemically as V. fluvialis from Cyprinus carpio/Labeo rohita; V. parahaemolyticus from Macrobrachium rosenbergii and V. harveyi from Macrobrachium malcomsoni. The genetic relationship among these Vibrio species was carried out by polymerase chain reaction (PCR) amplification of 16S rRNA gene followed by restriction digestion with Hae III, Bam HI and Pst I. ...

  6. Synthesis of new 3-and 4-substituted analogues of acyl homoserine lactone quorum sensing autoinducers

    DEFF Research Database (Denmark)

    Olsen, Jacob Alsbæk; Severinsen, Rune Eg; Rasmussen, Thomas Bovbjerg

    2002-01-01

    The quorum sensing mechanism in Gram-negative bacteria uses small intercellular signal molecules, N-acyl-homoserine lactones (AHLs), to control transcription of specific genes in relation to population density. In this communication, we describe the parallel synthesis of new AHL analogues, in which...... substituents have been introduced into the 3- and 4-positions of the lactone ring. These analogues have been screened for their ability to activate and inhibit a Vibrio fischeri LuxI/LuxR-derived quorum sensing reporter system....

  7. Eye-specification genes in the bacterial light organ of the bobtail squid Euprymna scolopes, and their expression in response to symbiont cues

    OpenAIRE

    Peyer, Suzanne M.; Pankey, M. Sabrina; Oakley, Todd H.; McFall-Ngai, Margaret J.

    2013-01-01

    The squid Euprymna scolopes has evolved independent sets of tissues capable of light detection, including a complex eye and a photophore or ‘light organ’, which houses the luminous bacterial symbiont Vibrio fischeri. As the eye and light organ originate from different embryonic tissues, we examined whether the eye-specification genes, pax6, eya, six, and dac, are shared by these two organs, and if so, whether they are regulated in the light organ by symbiosis. We obtained sequences of the fou...

  8. Vibrio trends in the ecology of the Venice lagoon.

    Science.gov (United States)

    Rahman, Mohammad Shamsur; Martino, Maria Elena; Cardazzo, Barbara; Facco, Pierantonio; Bordin, Paola; Mioni, Renzo; Novelli, Enrico; Fasolato, Luca

    2014-04-01

    Vibrio is a very diverse genus that is responsible for different human and animal diseases. The accurate identification of Vibrio at the species level is important to assess the risks related to public health and diseases caused by aquatic organisms. The ecology of Vibrio spp., together with their genetic background, represents an important key for species discrimination and evolution. Thus, analyses of population structure and ecology association are necessary for reliable characterization of bacteria and to investigate whether bacterial species are going through adaptation processes. In this study, a population of Vibrionaceae was isolated from shellfish of the Venice lagoon and analyzed in depth to study its structure and distribution in the environment. A multilocus sequence analysis (MLSA) was developed on the basis of four housekeeping genes. Both molecular and biochemical approaches were used for species characterization, and the results were compared to assess the consistency of the two methods. In addition, strain ecology and the association between genetic information and environment were investigated through statistical models. The phylogenetic and population analyses achieved good species clustering, while biochemical identification was demonstrated to be imprecise. In addition, this study provided a fine-scale overview of the distribution of Vibrio spp. in the Venice lagoon, and the results highlighted a preferential association of the species toward specific ecological variables. These findings support the use of MLSA for taxonomic studies and demonstrate the need to consider environmental information to obtain broader and more accurate bacterial characterization.

  9. Antagonistic Activities of Purple Non-sulfur Bacterial Extracts Against Antibiotic Resistant Vibrio sp.

    Directory of Open Access Journals (Sweden)

    Chandrasekaran, R.

    2011-01-01

    Full Text Available Solvent extracts of native purple non-sulfur bacterial (PNSB isolates from the effluents of brackish shrimp culture ponds, near Nagapattinam coast (South India were evaluated for antibacterial activity by the disc diffusion method. Best results were shown by the chloroform extracts against oxytetracycline resistant Vibrio harveyi and Vibrio fischerii. Among the purple non-sulfur bacterial isolates, Rhodobacter sphaeroides, showed maximum antagonistic activity. The findings suggest that the antagonistic extracts from Rba. sphaeroides could be used as an effective antibiotic in controlling Vibrio spp., in aquaculture systems.

  10. Ecotoxicological evaluation of industrial port of Venice (Italy) sediment samples after a decontamination treatment.

    Science.gov (United States)

    Libralato, Giovanni; Losso, Chiara; Arizzi Novelli, Alessandra; Citron, Marta; Della Sala, Stefano; Zanotto, Emanuele; Cepak, Franka; Volpi Ghirardini, Annamaria

    2008-12-01

    This work assesses the ecotoxicological effects of polluted sediment after a decontamination treatment process using a new sediment washing technique. Sediment samples were collected from four sites in Marghera Port industrial channels (Venice, Italy). Ecotoxicological evaluations were performed with Vibrio fischeri and Crassostrea gigas bioassays. Whole sediment and elutriate were deemed as the most suitable environmental matrices for this study. Toxicity scores developed in the Lagoon of Venice for V. fischeri on whole sediment and for C. gigas on elutriate were considered for the final ranking of samples. Ecotoxicological results showed that the treated sediment samples presented both acute and sub-chronic toxicities, which were mainly attributed to the presence of some remaining chemicals such as metals and polyaromatic hydrocarbons. The acute toxicity ranged from low to medium, while the sub-chronic one from absent to very high, suggesting that treated sediments could not be reused in direct contact with seawater.

  11. Microbiota of Vibrio sp. in the hepatopancreas of cultured white pacific shrimp (Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Renata Albuquerque C.

    2013-08-01

    Full Text Available Objective. The present study aimed to investigate the presence of vibrios in the hepatopancreas of cultured shrimp. Materials and methods. Vibrios from the hepatopancreas of fifteen samples of five specimens each, of apparently healthy Pacific white shrimp (Litopenaeus vannamei were isolated, identified and quantified. Results. The vibrio density ranged from 430 to 2,400 MPN g-1 (rs MPN cm-1=-0.114; rs MPN g-1 = 0.211. Thirty isolations were obtained, most of which belonged to the species V. cholerae (n=11 and V. parahaemolyticus (n=7. Conclusions. The outcomes of the present study suggest that, even in the absence of symptoms of vibriosis, the microbiota of the hepatopancreas of cultured shrimp may include sucrose positive and negative vibrios.

  12. Antimicrobial effect of dietary oregano essential oil against Vibrio bacteria in shrimps

    Directory of Open Access Journals (Sweden)

    Gracia-Valenzuela M.H.

    2014-01-01

    Full Text Available The effect of dietary oregano essential oils on the growth of Vibrio bacteria in shrimps was evaluated. Shrimps were fed: (i food with oregano oil with a high level of thymol; (ii food with oregano oil with a high level of carvacrol, and (iii food without oregano oil (the control. The animals were infected by three species of Vibrio (vulnificus, parahaemolyticus and cholerae. The microbial counts of Vibrio species were significantly lower (p <0.05 in tissues from animals whose food was supplemented with oregano oil. We concluded that dietary supplementation of shrimps with oregano oil provides antimicrobial activity into the body of the penaeids.

  13. Role and regulation of the orphan AphA protein of quorum sensing in pathogenic Vibrios.

    Science.gov (United States)

    Lu, Renfei; Osei-Adjei, George; Huang, Xinxiang; Zhang, Yiquan

    2018-03-01

    Quorum sensing (QS), a cell-to-cell communication process, is widely distributed in the bacterial kingdom. Bacteria use QS to control gene expression in response to cell density by detecting the signal molecules called autoinducers. AphA protein is the master QS regulator of vibrios operating at low cell density. It regulates the expression of a variety of genes, especially those encoding virulence factors, flagella/motility and biofilm formation. The role and regulation of AphA in vibrios, especially in human pathogenic vibrios, are summarized in this review. Clarification of the roles of AphA will help us to understand the pathogenesis of vibrios.

  14. Morphological adaptations in filtering screens of Daphnia galeata to food quantity and food quality

    NARCIS (Netherlands)

    Repka, S.; Veen, A.; Vijverberg, J.

    1999-01-01

    We reared clones of the waterflea Daphnia galeata, a common grazer in many types of lakes, under several food regimes to study adaptations to feeding conditions in filter screen morphology and life history. As food regimes, we used low and high concentrations of the green alga Scenedesmus, a high

  15. Dynamics of Vibrio with virulence genes detected in Pacific harbor seals (Phoca vitulina richardii) off California: implications for marine mammal health.

    Science.gov (United States)

    Hughes, Stephanie N; Greig, Denise J; Miller, Woutrina A; Byrne, Barbara A; Gulland, Frances M D; Harvey, James T

    2013-05-01

    Given their coastal site fidelity and opportunistic foraging behavior, harbor seals (Phoca vitulina) may serve as sentinels for coastal ecosystem health. Seals using urbanized coastal habitat can acquire enteric bacteria, including Vibrio that may affect their health. To understand Vibrio dynamics in seals, demographic and environmental factors were tested for predicting potentially virulent Vibrio in free-ranging and stranded Pacific harbor seals (Phoca vitulina richardii) off California. Vibrio prevalence did not vary with season and was greater in free-ranging seals (29 %, n = 319) compared with stranded seals (17 %, n = 189). Of the factors tested, location, turbidity, and/or salinity best predicted Vibrio prevalence in free-ranging seals. The relationship of environmental factors with Vibrio prevalence differed by location and may be related to oceanographic or terrestrial contributions to water quality. Vibrio parahaemolyticus, Vibrio alginolyticus, and Vibrio cholerae were observed in seals, with V. cholerae found almost exclusively in stranded pups and yearlings. Additionally, virulence genes (trh and tdh) were detected in V. parahaemolyticus isolates. Vibrio cholerae isolates lacked targeted virulence genes, but were hemolytic. Three out of four stranded pups with V. parahaemolyticus (trh+ and/or tdh+) died in rehabilitation, but the role of Vibrio in causing mortality is unclear, and Vibrio expression of virulence genes should be investigated. Considering that humans share the environment and food resources with seals, potentially virulent Vibrio observed in seals also may be of concern to human health.

  16. Increases in the amounts of Vibrio spp. in oysters upon addition of exogenous bacteria.

    Science.gov (United States)

    Froelich, Brett; Oliver, James

    2013-09-01

    The bacterial pathogen Vibrio vulnificus is found naturally in brackish coastal waters but can be greatly concentrated by filter-feeding organisms such as shellfish. Numerous experiments in which exogenous V. vulnificus cells are added to oysters in an attempt to measure uptake and depuration have been performed. In nearly all cases, results have shown that laboratory-grown bacteria are rapidly taken up by the oysters but ultimately eliminated, while naturally present Vibrio populations in oysters are resistant to depuration. In this study, oysters harvested during winter months, with low culturable Vibrio concentrations, were incubated in aquaria supplemented with strains of V. vulnificus that were either genotypically or phenotypically distinct from the background bacteria. These exogenous cells were eliminated from the oysters, as previously seen, but other vibrios already inhabiting the oysters responded to the V. vulnificus inoculum by rapidly increasing in number and maintaining a large stable population. The presence of such an oyster-adapted Vibrio population would be expected to prevent colonization by exogenous V. vulnificus cells, thus explaining the rapid depuration of these added bacteria.

  17. EFFECTIVE CONCENTRATIONS OF 6 CONTAMINANTS TO LEMMA MINOR, PIMEPHALES PROMELA, DAPHNIA MAGNA, AND CERIODAPHNIA DUBIA

    Science.gov (United States)

    The research presented here resulted in EC50 and LOEC values for the contaminants copper, cadmium, diazinon, atrazine, and cyanide to the species Lemna Minor, Pimephales promelas, Daphnia magna, and Ceriodaphnia dubia. Observed values were used as benchmarks for assessing the se...

  18. Draft Genome Sequence of Serratia sp. Strain DD3, Isolated from the Guts of Daphnia magna

    OpenAIRE

    Poehlein, Anja; Freese, Heike M.; Daniel, Rolf; Simeonova, Diliana D.

    2014-01-01

    We report the draft genome sequence of Serratia sp. strain DD3, a gammaproteobacterium from the family Enterobacteriaceae. It was isolated from homogenized guts of Daphnia magna. The genome size is 5,274 Mb. peerReviewed

  19. Transcontinental phylogeography of the Daphnia pulex species complex.

    Science.gov (United States)

    Crease, Teresa J; Omilian, Angela R; Costanzo, Katie S; Taylor, Derek J

    2012-01-01

    Daphnia pulex is quickly becoming an attractive model species in the field of ecological genomics due to the recent release of its complete genome sequence, a wide variety of new genomic resources, and a rich history of ecological data. Sequences of the mitochondrial NADH dehydrogenase subunit 5 and cytochrome c oxidase subunit 1 genes were used to assess the global phylogeography of this species, and to further elucidate its phylogenetic relationship to other members of the Daphnia pulex species complex. Using both newly acquired and previously published data, we analyzed 398 individuals from collections spanning five continents. Eleven strongly supported lineages were found within the D. pulex complex, and one lineage in particular, panarctic D. pulex, has very little phylogeographical structure and a near worldwide distribution. Mismatch distribution, haplotype network, and population genetic analyses are compatible with a North American origin for this lineage and subsequent spatial expansion in the Late Pleistocene. In addition, our analyses suggest that dispersal between North and South America of this and other species in the D. pulex complex has occurred multiple times, and is predominantly from north to south. Our results provide additional support for the evolutionary relationships of the eleven main mitochondrial lineages of the D. pulex complex. We found that the well-studied panarctic D. pulex is present on every continent except Australia and Antarctica. Despite being geographically very widespread, there is a lack of strong regionalism in the mitochondrial genomes of panarctic D. pulex--a pattern that differs from that of most studied cladocerans. Moreover, our analyses suggest recent expansion of the panarctic D. pulex lineage, with some continents sharing haplotypes. The hypothesis that hybrid asexuality has contributed to the recent and unusual geographic success of the panarctic D. pulex lineage warrants further study.

  20. Isolation and molecular identification of Vibrio spp. by sequencing of 16S rDNA from seafood, meat and meat products in Libya

    OpenAIRE

    S.M. Azwai; E.A. Alfallani; S.K. Abolghait; A.M. Garbaj; H.T. Naas; A.A. Moawad; F.T. Gammoudi; H.M. Rayes; I. Barbieri; I.M. Eldaghayes

    2016-01-01

    The genus Vibrio includes several food-borne pathogens that cause a spectrum of clinical conditions including septicemia, cholera and milder forms of gastroenteritis. Several Vibrio spp. are commonly associated with food-borne transmission including Vibrio cholerae, Vibrio parahemolyticus, and Vibrio vulnificus. Microbiological analysis for enumeration and isolation of Vibrio spp. were carried out for a total of 93 samples of seafood, meat and meat products from different geographic localitie...

  1. PREVALENCE AND IDENTIFICATION OF VIBRIO SPP. ISOLATED ON AQUACULTURED GILTHEAD SEA BREAM

    Directory of Open Access Journals (Sweden)

    C. Scarano

    2011-01-01

    Full Text Available The aim of the study was to investigate the prevalence of Vibrio spp isolated from gilthead sea bream (Sparus aurata farmed on sea cages and to identify and characterize the pathogen by molecular techniques. Eighty fish were collected from two hatcheries located on the North-Est Sardinian Mediterranean coast, and microbiological analysis were performed on different body parts such as skin, gills, muscle and intestinal tract. Subsequently 100 pure colonies with typical morphology and phenotypic characteristics were selected and submitted to the molecular identification. The analysis on the prevalence of Vibrio spp showed the effect of the hatchery rearing system (P<0.001, of the date of sampling (P<0.001, and of the body part (P<0.001. All the strains selected were confirmed to be members of the genus Vibrio spp by the molecular method/techinique/identification, whereas the rpoA gene sequence analyses allowed to identify 89 strains belonging to the species Vibrio harveyi, 6 to V. diabolicus, 2 to V. parahaemolyticus and 1 to V. mediterranei.

  2. Mechanistic study of the toxicity of ionizing radiation in Daphnia magna

    Energy Technology Data Exchange (ETDEWEB)

    Parisot, F.; Alonzo, F. [Institut de Radioprotection et de Surete Nucleaire, IRSN/PRP-ENV/SERIS/LECO, Laboratoire d' Ecotoxicologie des Radionucleides, Cadarache (France); Bourdineaud, J.P. [UMR CNRS 5805 EPOC - OASU Station Marine d' Arcachon Universite Bordeaux 1, Arcachon (France); Poggiale, J.C. [Mediterranean Institute of Oceanography - MIO - UMR 7294 Pytheas Institute - OSU, Aix-Marseille University, Marseille (France)

    2014-07-01

    In the last decade, the ecological impact of ionizing radiation has emerged as a growing scientific concern for ecosystems protection. However, the assessment of potential radiological effects on the environment is hampered by both a gap of available scientific data and a lack in proven methods. Understanding how ionizing radiation affects wildlife at biologically and ecologically relevant scales is a major issue in environmental protection. This issue is one of the objectives of the Strategic Research Agenda (SRA) developed in the framework of the European program STAR (Strategy for Allied Radioecology). In this context, the present PhD project aims to evaluate chronic effects of external Cs-137 gamma radiation at low doses on a representative species of aquatic ecosystems, the cladoceran crustacean Daphnia magna. More precisely, the objectives of this study are to evaluate multi-generational effects of irradiation on: (i) genotoxic effects and their potential consequences on survival, somatic growth and fecundity, (ii) the energy budget and (iii) the population dynamics of Daphnia. An experimental design was developed to expose daphnids to low doses of ionizing radiation ranging from 0,008 to 32 mGy.h{sup -1} across 3 successive generations (75 days). DNA damages were assessed using random amplified polymorphic DNA and real time PCR (RAPD - PCR). Effects on survival, somatic growth and fecundity were monitored for 21-25 days in each generation, from hatching to release of brood 5. Our aim is to: examine a potential correlation between molecular (DNA) damage and effects observed at the individual level (survival, somatic growth and fecundity) across generations and test the suitability of DNA damage as an early indice of future trans-generational effects. As a future perspective, individual and molecular effects data will be analysed using a DEBtox model (Dynamic Energy Budget Applied to Toxicology) in order to identify the metabolic modes of action of ionizing

  3. Density and depth variations of Daphnia multilocus genotypes during a summer period in Lake Maarsseveen

    NARCIS (Netherlands)

    Ringelberg, J.; van Gool, E.; Brehm, Michaela

    2004-01-01

    The genotype composition of a Daphnia population complex during a summer period in Lake Maarsseveen (The Netherlands) was determined by allozyme analysis. The depth distribution, diel vertical migration and several parameters of the total population were measured. Young-of-the-year (0+) perch (Perca

  4. Screening of probiotic bacteria and its role on artificial infection of Vibrio harvey in white shrimp (Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    . Sukenda

    2007-07-01

    Full Text Available Probiotic was screened from 28 strains of normal bacterial flora isolated from rearing water in a Litopenaeus vannamei farm based on its inhibitory activity against the growth of Vibrio harveyi.  Antibacterial activity was also tested in vivo to V. harveyi in L. vannamei.  The result showed that  the probiotic has a antibacterial effect on V. harveyi.  The in vivo test showed that shrimps injected with probiotic previously before challenged with V. harveyi has survival higher than control.  Probiotic isolate was suspected as Vibrio furnissi. Keywords:  biocontrol, inhibitory activity, Vibrio furnissi, Vibrio harveyi, Litopenaeus vannamei   AbstraK Bakteri probiotik ditapis dari 28 strain bacteria flora yang diisolasi dari air pemeliharaan udang vaname Litopenaeus vannamei berdasarkan aktivitas penghambatannya terhadap pertumbuhan Vibrio harveyi.  Aktivitas bakteri probiotik juga diuji secara in vivo terhadap V. harveyi pada udang putih.  Hasil penelitian menunjukkan bahwa bakteri probiotik isolat memiliki kemampuan antibakteria terhadap V. harveyi.  Uji in vivo menunjukkan bahwa udang yang diinjeksi probiotik sebelum diuji tantang dengan V. harveyi memiliki kelangsungan hidup lebih tinggi daripada kontrol.  Isolat probiotik tersebut diduga adalah Vibrio furnissi. Kata kunci:  biokontrol, aktivitas penghambatan, Vibrio furnissi, Vibrio harveyi, Litopenaeus vannamei

  5. Reducing oyster-associated bacteria levels using supercritical fluid CO2 as an agent of warm pasteurization.

    Science.gov (United States)

    Meujo, Damaris A F; Kevin, Dion A; Peng, Jiangnan; Bowling, John J; Liu, Jianping; Hamann, Mark T

    2010-03-31

    An innovative approach to Post-Harvest Processing (PHP) of oysters is introduced focusing on the effects of supercritical carbon dioxide (scCO(2)) on bacterial contaminants trapped in the digestive system of oysters. Oysters were exposed to scCO(2) under two conditions: (1) 100 bar and 37 degrees C for 30 min and (2) 172 bar and 60 degrees C for 60 min. Using FDA standard guidelines for food analysis, variations in the Aerobic Plate Count (APC) were assessed. It was established that exposing oysters to CO(2) at 100 bar and 37 degrees C for 30 min and at 172 bar and 60 degrees C for 60 min induced 2-log and 3-log reductions in the APC respectively. The decrease in the microbial load as a result of treatment with scCO(2) was found to be significant (P=0.002). A release of adductor muscles from the shell was noted in oysters treated at 172 bar and 60 degrees C for 60 min; this was not the case for oysters treated at 100 bar and 37 degrees C for 30 min. A blind study allowing sensory analysis of treated vs. untreated oysters was also completed and no significant change in the physical appearance, smell, or texture was recorded. In this paper, we also report the effect of scCO(2) on several bacterial isolates, including a referenced ATCC strain of a non-pathogenic Vibrio (Vibrio fischeri) as well as several other bacterial isolates cultured from oyster' tissues and found to share biochemical features common to pathogenic Vibrio strains. A complete inactivation (minimum 7-log reduction) was achieved with these latter bacterial isolates. A 6-log reduction was observed with V. fischeri. Copyright 2009 Elsevier B.V. All rights reserved.

  6. 21 CFR 866.3930 - Vibrio cholerae serological reagents.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3930 Vibrio... from cultured isolates derived from clinical specimens. The identification aids in the diagnosis of...

  7. Variable-number tandem repeats as molecular markers for biotypes of Pasteuria ramosa in Daphnia spp.

    Science.gov (United States)

    Mouton, Laurence; Nong, Guang; Preston, James F; Ebert, Dieter

    2007-06-01

    Variable-number tandem repeats (VNTRs) have been identified in populations of Pasteuria ramosa, a castrating endobacterium of Daphnia species. The allelic polymorphisms at 14 loci in laboratory and geographically diverse soil samples showed that VNTRs may serve as biomarkers for the genetic characterization of P. ramosa isolates.

  8. Accumulation of dieldrin in an alga (Scenedesmus obliquus), Daphnia magna, and the guppy (Poecilia reticulata)

    Science.gov (United States)

    Reinert, Robert E.

    1972-01-01

    Scenedesmus obliquus, Daphnia magna, and Poecilia reticulata accumulated dieldrin directly from water; average concentration factors (concentration in organism, dry weight, divided by concentration in water) were 1282 for the alga, 13,954 for D. magna, and 49,307 (estimated) for the guppy. The amount accumulated by each species at equilibrium (after about 1.5, 3-4, and 18 days, respectively) was directly proportional to the concentration of dieldrin in the water. Daphnia magna and guppies accumulated more dieldrin from water than from food that had been exposed to similar concentrations in water. When guppies were fed equal daily rations of D. magna containing different concentrations of insecticide, the amounts of dieldrin accumulated by the fish were directly proportional to the concentration in D. magna; when two lots of guppies were fed different quantities of D. magna (10 and 20 organisms per day) containing identical concentrations of dieldrin, however, the amounts accumulated did not differ substantially.

  9. Electroantennogram measurement of the olfactory response of Daphnia spp. and its impairment by waterborne copper.

    Science.gov (United States)

    Simbeya, Christy K; Csuzdi, Catherine E; Dew, William A; Pyle, Greg G

    2012-08-01

    In this study an electroantennogram (EAG) method was developed for use on live daphniids. The EAG response of Daphnia magna and Daphnia pulex to a variety of amino acids was measured. The strongest response measured was elicited by L-arginine and was shown to induce a concentration-dependent response indicating the response is olfactory in nature. Subsequent exposures of D. magna to a low, ecologically-relevant concentration of copper (7.5 μg/L) showed a disruption in EAG function. This study utilizes the development of an EAG method for measuring olfactory acuity of live daphniids and demonstrates that at ecologically-relevant concentrations, the olfactory dysfunction caused by copper can be detected. The EAG technique is a useful tool for investigating the olfactory response of daphniids to odourants at the cellular level and detecting the effects of toxicants on the olfactory acuity of daphniids. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Acute toxicity assessment of explosive-contaminated soil extracting solution by luminescent bacteria assays.

    Science.gov (United States)

    Xu, Wenjie; Jiang, Zhenming; Zhao, Quanlin; Zhang, Zhenzhong; Su, Hongping; Gao, Xuewen; Ye, Zhengfang

    2016-11-01

    Explosive-contaminated soil is harmful to people's health and the local ecosystem. The acute toxicity of its extracting solution was tested by bacterial luminescence assay using three kinds of luminescent bacteria to characterize the toxicity of the soil. An orthogonal test L 16 (4 5 ) was designed to optimize the soil extracting conditions. The optimum extracting conditions were obtained when the ultrasonic extraction time, ultrasonic extraction temperature, and the extraction repeat times were 6 h, 40 °C, and three, respectively. Fourier transform infrared spectroscopy (FTIR) results showed that the main components of the contaminated soil's extracting solution were 2,4-dinitrotoluene-3-sulfonate (2,4-DNT-3-SO 3 - ); 2,4-dinitrotoluene-5-sulfonate (2,4-DNT-5-SO 3 - ); and 2,6-dinitrotoluene (2,6-DNT). Compared with Photobacterium phosphoreum and Vibrio fischeri, Vibrio qinghaiensis sp. Nov. is more suitable for assessing the soil extracting solution's acute toxicity. Soil washing can remove most of the contaminants toxic to luminescent bacterium Vibrio qinghaiensis sp. Nov., suggesting that it may be a potential effective remediation method for explosive-contaminated soil.

  11. Efek Antibakteri Ekstrak Daun Mimba (Azadirachta indica A. Juss) terhadap Bakteri Vibrio algynoliticus Secara In Vitro

    OpenAIRE

    Uli Ayini; Siti Harnina B.; Titis Candra Dewi

    2014-01-01

    Budidaya udang windu di Indonesia telah berkembang pesat. Salah satu kendala budidaya udang adalah penyakit Vibriosis yang disebabkan oleh bakteri Vibrio algynoliticus. Tujuan penelitian ini adalah untuk mengetahui efek antibakeri ekstrak daun mimba terhadap bakteri Vibrio algynoliticus. Penelitian ini menggunakan metode dilusi untuk mengetahui efek antibakteri ekstrak daun mimba terhadap bakteri Vibrio algynoliticus secara in vitro. Konsentrasi ekstrak yang digunakan (%) yaitu: 0; 2,5; 5; 7,...

  12. Vibrio harveyi modulated gene expression in Penaeus monodon and Fenneropenaeus indicus

    Digital Repository Service at National Institute of Oceanography (India)

    Nayak, S.

    : Gammaproteobacteria Order : Vibrionales Family : Vibrionaceae Genus : Vibrio Species : harveyi Vibrio harveyi is a Gram-negative bioluminescent marine bacterium. It is both a free- living, as well as a symbiont with many... marine animals. In free-living form, it can be found throughout the water column, in the sediment as well as on the exterior surfaces of marine organisms. It causes systemic infection resulting in mortalities in larvae and post-larvae, which sometimes...

  13. UV-Stressed Daphnia pulex Increase Fitness through Uptake of Vitamin D3.

    Directory of Open Access Journals (Sweden)

    Sandra J Connelly

    Full Text Available Ultraviolet radiation is known to be highly variable in aquatic ecosystems. It has been suggested that UV-exposed organisms may demonstrate enough phenotypic plasticity to maintain the relative fitness of natural populations. Our long-term objective is to determine the potential photoprotective effect of vitamin D3 on Daphnia pulex exposed to acute or chronic UV radiation. Herein we report our initial findings in this endeavor. D. pulex survival and reproduction (fitness was monitored for 5 d as a proof of concept study. Significantly higher fitness was observed in the D. pulex with D3 than those without (most extreme effects observed were 0% survival in the absence of D3 and 100% with 10 ppm D3. Vitamin D3 was isolated from the culture media, the algal food (Pseudokirchneriella, and the D. pulex and quantified using high performance liquid chromatography (HPLC. Vitamin D3 was fluorescently labeled using a phenothiazinium dye and added to cultures of D. pulex. Images demonstrating the uptake of D3 into the tissues and carapace of the D. pulex were acquired. Our initial findings suggest a positive role for D3 in ecosystems as both UV-stressed algae and Daphnia sequester D3, and D. pulex demonstrate increased fitness in the presence of D3.

  14. Inactivation of Vibrio parahaemolyticus and Vibrio vulnificus in oysters by high-hydrostatic pressure and mild heat.

    Science.gov (United States)

    Ye, Mu; Huang, Yaoxin; Chen, Haiqiang

    2012-10-01

    Several recent outbreaks associated with oysters have heightened safety concerns of raw shellfish consumptions, with the majority being attributed to Vibrio spp. The objective of this study was to determine the effect of high-hydrostatic pressure (HHP) followed by mild heating on the inactivation of Vibrio parahaemolyticus and Vibrio vulnificus in live oysters. Inoculated oysters were randomly subjected to: a) pressurization at 200-300 MPa for 2 min at 21 °C, b) mild heat treatment at 40, 45 or 50 °C for up to 20 min and c) pressure treatment of 200-300 MPa for 2 min at 21 °C followed by heat treatment at 40-50 °C. Counts of V. parahaemolyticus and V. vulnificus were then determined using the most probable number (MPN) method. Pressurization at 200-300 MPa for 2 min resulted in various degrees of inactivation, from 1.2 to >7 log MPN/g reductions. Heat treatment at 40 and 45 °C for 20 min only reduced V. parahaemolyticus and V. vulnificus by 0.7-2.5 log MPN/g while at 50 °C for 15 min achieved >7 log MPN/g reduction. HHP and mild heat had synergistic effects. Combinations such as HHP at 250 MPa for 2 min followed by heat treatment at 45 °C for 15 min and HHP at 200 MPa for 2 min followed by heat treatment at 50 °C for 5 min reduced both V. parahaemolyticus and V. vulnificus to non-detectable levels by the MPN method (oysters (negative enrichment results). This study demonstrated the efficiency of HHP followed by mild heat treatments on inactivation of V. parahaemolyticus and V. vulnificus and could help the industry to establish parameters for processing oysters. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Mortalities of Eastern and Pacific oyster Larvae caused by the pathogens Vibrio coralliilyticus and Vibrio tubiashii.

    Science.gov (United States)

    Richards, Gary P; Watson, Michael A; Needleman, David S; Church, Karlee M; Häse, Claudia C

    2015-01-01

    Vibrio tubiashii is reported to be a bacterial pathogen of larval Eastern oysters (Crassostrea virginica) and Pacific oysters (Crassostrea gigas) and has been associated with major hatchery crashes, causing shortages in seed oysters for commercial shellfish producers. Another bacterium, Vibrio coralliilyticus, a well-known coral pathogen, has recently been shown to elicit mortality in fish and shellfish. Several strains of V. coralliilyticus, such as ATCC 19105 and Pacific isolates RE22 and RE98, were misidentified as V. tubiashii until recently. We compared the mortalities caused by two V. tubiashii and four V. coralliilyticus strains in Eastern and Pacific oyster larvae. The 50% lethal dose (LD50) of V. coralliilyticus in Eastern oysters (defined here as the dose required to kill 50% of the population in 6 days) ranged from 1.1 × 10(4) to 3.0 × 10(4) CFU/ml seawater; strains RE98 and RE22 were the most virulent. This study shows that V. coralliilyticus causes mortality in Eastern oyster larvae. Results for Pacific oysters were similar, with LD50s between 1.2 × 10(4) and 4.0 × 10(4) CFU/ml. Vibrio tubiashii ATCC 19106 and ATCC 19109 were highly infectious toward Eastern oyster larvae but were essentially nonpathogenic toward healthy Pacific oyster larvae at dosages of ≥1.1 × 10(4) CFU/ml. These data, coupled with the fact that several isolates originally thought to be V. tubiashii are actually V. coralliilyticus, suggest that V. coralliilyticus has been a more significant pathogen for larval bivalve shellfish than V. tubiashii, particularly on the U.S. West Coast, contributing to substantial hatchery-associated morbidity and mortality in recent years. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  16. Prevalence of listeria, Aeromonas, and Vibrio species in fish used for human consumption in Turkey.

    Science.gov (United States)

    Yücel, Nihal; Balci, Senay

    2010-02-01

    A total of 78 raw retail fish samples from 30 freshwater and 48 marine fish were examined for the presence of Listeria, Aeromonas, and Vibrio species. The overall incidence of Listeria spp. was 30% in freshwater samples and 10.4% in marine fish samples. Listeria monocytogenes (44.5%) was the most commonly isolated species in freshwater fish, and Listeria murrayi (83.5%) was the most commonly isolated species in marine fish samples. Motile aeromonads were more common in marine fish samples (93.7%) than in freshwater fish samples (10%). Vibrio alginolyticus, Vibrio fluvialis, and Vibrio damsela were isolated only in marine fish samples, representing 40.9, 38.6, and 36.3% of Vibrio isolates, respectively. In freshwater and marine fish, the highest incidences of Listeria and Aeromonas were found in skin samples; the highest incidence of Vibrio in marine fish was found in gill samples. The location of Listeria spp. and L. monocytogenes in a fish was significantly different among freshwater fish. A high incidence of these bacterial pathogens was found in the brown trout (Salmo trutta) and horse mackerel (Trachurus trachurus). Handling of contaminated fish, cross-contamination, or eating raw fish might pose a health hazard, especially in immunosuppressed individuals, elderly people, and children. This study highlights the importance of bacterial pathogens in fish intended for human consumption, but more study is needed.

  17. Relationships between Environmental Factors and Pathogenic Vibrios in the Northern Gulf of Mexico ▿ †

    Science.gov (United States)

    Johnson, C. N.; Flowers, A. R.; Noriea, N. F.; Zimmerman, A. M.; Bowers, J. C.; DePaola, A.; Grimes, D. J.

    2010-01-01

    Although autochthonous vibrio densities are known to be influenced by water temperature and salinity, little is understood about other environmental factors associated with their abundance and distribution. Densities of culturable Vibrio vulnificus containing vvh (V. vulnificus hemolysin gene) and V. parahaemolyticus containing tlh (thermolabile hemolysin gene, ubiquitous in V. parahaemolyticus), tdh (thermostable direct hemolysin gene, V. parahaemolyticus pathogenicity factor), and trh (tdh-related hemolysin gene, V. parahaemolyticus pathogenicity factor) were measured in coastal waters of Mississippi and Alabama. Over a 19-month sampling period, vibrio densities in water, oysters, and sediment varied significantly with sea surface temperature (SST). On average, tdh-to-tlh ratios were significantly higher than trh-to-tlh ratios in water and oysters but not in sediment. Although tlh densities were lower than vvh densities in water and in oysters, the opposite was true in sediment. Regression analysis indicated that SST had a significant association with vvh and tlh densities in water and oysters, while salinity was significantly related to vibrio densities in the water column. Chlorophyll a levels in the water were correlated significantly with vvh in sediment and oysters and with pathogenic V. parahaemolyticus (tdh and trh) in the water column. Furthermore, turbidity was a significant predictor of V. parahaemolyticus density in all sample types (water, oyster, and sediment), and its role in predicting the risk of V. parahaemolyticus illness may be more important than previously realized. This study identified (i) culturable vibrios in winter sediment samples, (ii) niche-based differences in the abundance of vibrios, and (iii) predictive signatures resulting from correlations between environmental parameters and vibrio densities. PMID:20817802

  18. The effects of food availability on growth and reproduction of Daphnia magna exposed to silver nanoparticles

    DEFF Research Database (Denmark)

    Mackevica, Aiga; Skjolding, Lars Michael; Gergs, A.

    ) were performed using 30 nm citric acid stabilized AgNP. The aim of the study was, besides providing data for the chronic toxicity of AgNP, to study the influence of the food availability on the reproductive toxicity of AgNP in Daphnia magna. The exposure concentrations applied ranged from 2 to 50 μg...... to controls, whereas concentrations above 10 μgAg/L resulted in inhibition of growth and reproduction as well as an increased mortality. The addition of higher amounts of food showed a beneficial effect on animal survival, growth and reproduction. Similar as in normal food availability treatment, animals......The number of available studies on the acute effects of silver nanoparticles (AgNP) on aquatic organisms has increased dramatically in recent years, but there is still very limited information available on chronic effects. In this study, a series of Daphnia magna 21-days reproduction test (OECD 211...

  19. Use of Hybridization Chain Reaction-Fluorescent In Situ Hybridization To Track Gene Expression by Both Partners during Initiation of Symbiosis.

    Science.gov (United States)

    Nikolakakis, K; Lehnert, E; McFall-Ngai, M J; Ruby, E G

    2015-07-01

    The establishment of a productive symbiosis between Euprymna scolopes, the Hawaiian bobtail squid, and its luminous bacterial symbiont, Vibrio fischeri, is mediated by transcriptional changes in both partners. A key challenge to unraveling the steps required to successfully initiate this and many other symbiotic associations is characterization of the timing and location of these changes. We report on the adaptation of hybridization chain reaction-fluorescent in situ hybridization (HCR-FISH) to simultaneously probe the spatiotemporal regulation of targeted genes in both E. scolopes and V. fischeri. This method revealed localized, transcriptionally coregulated epithelial cells within the light organ that responded directly to the presence of bacterial cells while, at the same time, provided a sensitive means to directly show regulated gene expression within the symbiont population. Thus, HCR-FISH provides a new approach for characterizing habitat transition in bacteria and for discovering host tissue responses to colonization. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  20. Daphnia as a model organism in limnology and aquatic biology: introductory remarks

    Czech Academy of Sciences Publication Activity Database

    Seďa, Jaromír; Petrusek, A.

    2011-01-01

    Roč. 70, č. 2 (2011), s. 337-344 ISSN 1129-5767. [International Conference on Invertebrate Reproduction and Development in the Age of Genetic Modifications. Praha, 16.08.2010-20.08.2010] R&D Projects: GA AV ČR(CZ) 1QS600170504 Institutional research plan: CEZ:AV0Z60170517 Keywords : Daphnia * senescence * cyanobacteria * inducible defences * flood impact * egg banks * fish predation Subject RIV: DA - Hydrology ; Limnology Impact factor: 1.207, year: 2011

  1. Potentials and limitations of adaptive plasticity in filtering screen morphology of Daphnia (Crustacea: Cladocera)

    Czech Academy of Sciences Publication Activity Database

    Macháček, Jiří; Seďa, Jaromír

    2016-01-01

    Roč. 38, č. 5 (2016), s. 1269-1280 ISSN 0142-7873 R&D Projects: GA ČR(CZ) GA206/09/1325; GA ČR(CZ) GA15-24309S Institutional support: RVO:60077344 Keywords : Daphnia * filtering screen morphology * transgenerational plasticity * ontogenetic plasticity * taxonspecific trait Subject RIV: EH - Ecology, Behaviour Impact factor: 1.983, year: 2016

  2. Detection of Vibrio parahaemolyticus and Vibrio cholerae in oyster, Crassostrea rhizophorae, collected from a natural nursery in the Cocó river estuary, Fortaleza, Ceará, Brazil Isolamento de Vibrio parahaemolyticus e Vibrio cholerae em ostras, Crassostrea rhizophorae, coletadas em um criadouro natural no estuário do rio Cocó, Fortaleza, Ceará, Brasil

    Directory of Open Access Journals (Sweden)

    Oscarina Viana de Sousa

    2004-04-01

    Full Text Available Oysters are edible organisms that are often ingested partially cooked or even raw, presenting therefore a very high risk to the consumers' health, especially in tropical regions. The presence of Vibrio cholerae and Vibrio parahaemolyticus in oysters sampled at an estuary in the Brazilian northeastern region was studied, with 300 oysters tested through an 8-months period. The salinity of the water at the sampling point varied between 3% and 27‰. V. cholerae was the most frequently detected species (33.3% of the samples, and of the 22 V. cholerae isolates, 20 were identified as non-O1/non-O139, with two of the colonies presenting a rough surface and most of remaining ones belonging to the Heiberg II fermentation group. V. parahaemolyticus was isolated from just one of the samples. Other bacteria such as Providencia spp., Klebsiella spp. and Morganella morganii were also isolated.As ostras são alimentos marinhos freqüentemente ingeridos crus ou parcialmente cozidos. Por esta razão, o risco para a saúde dos consumidores desses produtos é muito elevado, principalmente, quando são de regiões tropicais. Foi estudada a presença de Vibrio cholerae e Vibrio parahaemolyticus em ostras de um estuário na região Nordeste do Brasil. Trezentas ostras foram analisadas, em um período de 8 meses. A salinidade da água, no local de coleta, variou de 3 a 27‰. V. cholerae foi o vibrio mais freqüentemente detectado (33,3% das amostras. Dos 22 isolados, 20 foram identificados como V. cholerae não-O1/não-O139, duas delas apresentando forma rugosa sendo a maioria das demais pertencente ao tipo fermentativo Heiberg II. V. parahaemolyticus foi isolado em apenas umas das coletas. Foram, também, identificadas nas amostras isolados de Providencia spp., Klebsiella spp., Proteus spp. e Morganella morganii.

  3. Factores ambientales vinculados con la aparición y dispersión de las epidemias de Vibrio en América del Sur Environmental drivers of emergence and spreading of Vibrio epidemics in South America

    Directory of Open Access Journals (Sweden)

    Ronnie G. Gavilán

    2011-03-01

    Full Text Available El Vibrio cholerae y el V. parahaemolyticus son las principales especies de Vibrio que ocasionan infecciones en seres humanos. Las infecciones causadas por estos dos patógenos están teniendo una creciente importancia debido a su imparable expansión a nivel mundial. En el presente artículo se resumen los aspectos ecológicos asociados con la llegada y dispersión de las epidemias por V. parahaemolyticus y V. cholera en Perú desde una perspectiva sudamericana. De igual forma, se discute las similitudes en la aparición del cólera en 1991 y las infecciones por V. parahaemolyticus en 1997 en Perú, que sirvieron como experimentos únicos para analizar la relación entre las epidemias de Vibrio y los cambios en el medio ambiente. Estas dos radiaciones epidémicas constituyen unos claros ejemplos que apoyan la teoría de la dispersión oceánica de vibrios patógenos y permiten identificar a los episodios de El Niño como un mecanismo potencial de transmisión de enfermedades a través del océano.Vibrio cholerae and V. parahaemolyticus are the two Vibrio species with a major impact on human health. Diseases caused by both pathogens are acquiring increasing relevance due to their expansion at global scale. In this paper, we resume the ecological aspects associated with the arrival and spreading of infections caused by V. parahaemolyticus and V. cholerae in Peru from a South American perspective. Moreover, we discuss the similarities in the emergence in Peru of cholera cases in 1991 and V. parahaemolyticus infections in 1997. These constituted exceptional experiments to evaluate the relationships between the Vibrio epidemics and changes in the environment. The epidemic radiations of V. cholerae and V. parahaemolyticus constitute to clear examples supporting the oceanic dispersion of pathogenic vibrios and have enabled the identification of El Niño events as a potential mechanism for the spreading of diseases through the ocean.

  4. Daphnia as an Emerging Epigenetic Model Organism

    Directory of Open Access Journals (Sweden)

    Kami D. M. Harris

    2012-01-01

    Full Text Available Daphnia offer a variety of benefits for the study of epigenetics. Daphnia’s parthenogenetic life cycle allows the study of epigenetic effects in the absence of confounding genetic differences. Sex determination and sexual reproduction are epigenetically determined as are several other well-studied alternate phenotypes that arise in response to environmental stressors. Additionally, there is a large body of ecological literature available, recently complemented by the genome sequence of one species and transgenic technology. DNA methylation has been shown to be altered in response to toxicants and heavy metals, although investigation of other epigenetic mechanisms is only beginning. More thorough studies on DNA methylation as well as investigation of histone modifications and RNAi in sex determination and predator-induced defenses using this ecologically and evolutionarily important organism will contribute to our understanding of epigenetics.

  5. Potensi Ekstrak Daun Binahong (Anredera cordifolia) Sebagai Penghambat Bakteri Vibrio harveyi

    OpenAIRE

    Gde Raka Angga Kartika; Sri Andayani; Soelistyowati Soelistyowati

    2016-01-01

    Binahong (Anredera cordifolia) is a plant that can treat various kinds of diseases, because this plant has a high antioxidant content and as an antibacterial and antiviral. Vibriosis disease caused by the bacterium Vibrio harveyi is a serious problem in marine and brackish culture, this disease can cause death for shrimp and fish that farmed in marine or brackish. This study aims to determine the potential of using leaf extract Binahong with different concentrations as Vibrio harveyi inhibiti...

  6. POTENCY OF VIBRIO ISOLATES FOR BIOCONTROL OF VIBRIOSIS IN TIGER SHRIMP (PENAEUS MONODON LARVAE

    Directory of Open Access Journals (Sweden)

    B. W. LAY

    2003-01-01

    Full Text Available This study was carried out to obtain Vibrio isolates able to function as biocontr ol of vibriosis in shrimp hatchery. Thirty one Vibrio isolates were isolated from tiger shrimp larvae and hatchery environments, i.e. Labuan, Pangandaran, and Lampung, Indonesia. Pathogenic V. harveyi MR5339 was obtained from Maros, South-Sulawesi and was made as a rifampicin resistant mutant (RFR to screen for those 31 Vibrio isolates in in vitro assays and to allow us to monitor their presence in shrimp larvae and larval rearing water. Almost all Vibrio isolates could inhibit the growth of pathogenic V. harveyi MR5339 RFR. SKT-b isolate from Skeletonema was the most effective to inhibit the growth of V. harveyi MR5339 Rf* and significantly reduced larval mortality in pathogen challenge assays. These prospective biocontrol bacteria, at concentration of 10" CFU/ml, did not show pathogenicity to shrimp larvae. SKT-b was Gram negative, short rod-shape, exhibited yellow colonies on TCBS and swarming on SWC-agar media, motile, u tilized glucose and sucrose but not lactose: produced extra-cellular protease and amylase, but did not produce chitmase. Partial sequencing of 16S-rRNA gene SKT-b showed SKT-b similarity to Vibrio alginofyticus.

  7. The positively phototactic reaction of daphnia magna straus: A contribution to the understanding of diurnal vertical migration

    NARCIS (Netherlands)

    Ringelberg, J.

    1964-01-01

    The present investigation was aimed at gaining more insight into the physiological mechanism underlying the diurnal vertical migration of planktonic animals. The experiments were carried out on Daphnia magna. Only reactions to decreases in light intensity were studied. Kinetical

  8. [Cytotoxic effect of Vibrio cholerae non-O1 on Vero cells].

    Science.gov (United States)

    Figueroa-Arredondo, P; García-Lozano, H; Gutiérrez-Cogco, L; Valdespino-Gómez, J L

    1994-01-01

    At the present time there is still in Mexico a diarrhoeal outbreak due to Vibrio cholerae O1. In INDRE we have isolated from the same outbreak last year (jan-apr), 70 strains of Vibrio cholerae Non-O1. These were isolated from patients with a diarrhoeal illness different from cholera. Patients were of different ages and sex, and from various geographic areas. The isolated strains were confirmed by serological agglutination test with polyclonal antisera, and they neither belong to O1 serogroup or O139. We assayed all the 70 strains in Vero cells, searching for cytotoxic effect, probably attributed to cholera toxin, or any other toxin. The strains were screened by PCR for cholera toxin gene detection, and negative results were obtained. We have found only one CT-producer strain, but it was a rough one so, we are not able to affirm that is not a V. cholerae O1 serotype. Vibrio cholerae Non-O1 strains, tested in Vero cells assay, produced cytotoxic effect within 24 h. It was found that 48/70 strains (66.6%), had cytotoxic activity, showing rounding and then lysis of cells. From our results we concluded that this cytotoxic effect, is not cholera toxin related, instead we propose it could be due to an unknown virulence factor, probably a different toxin in mexican Vibrio cholerae Non-O1 strains.

  9. Spectral SAR Ecotoxicology of Ionic Liquids: The Daphnia magna Case

    International Nuclear Information System (INIS)

    Putz, M.V.; Lacrama, A.M.; Ostafe, V.; Lacrama, A.M.

    2007-01-01

    Aiming to provide a unified theory of ionic liquids eco toxicity, the recent spectral structure activity relationship (S-SAR) algorithm is employed for testing the two additive models of anionic-cationic interaction containing ionic liquid activity: the causal and the endpoint, |0+> and |1+> models, respectively. As a working system, the Daphnia magna eco toxicity was characterized through the formulated and applied spectral chemical-eco biological interaction principles. Specific anionic-cationic-ionic-liquid rules of interaction along the developed mechanistic hypersurface map of the main eco toxicity paths together with the so-called resonance limitation of the standard statistical correlation analysis were revealed.

  10. Vibrio ecology in PNW - The Ecology of Vibrio parahaemolyticus in the Pacific Northwest: Implications for risk assessment and early warning systems

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Over the past decade, there has been a significant increase in Vibrio parahaemolyticus-related gastroenteritis from the consumption of raw oysters harvested in...

  11. Cryptic intercontinental colonization in water fleas Daphnia pulicaria inferred from phylogenetic analysis of mitochondrial DNA variation

    Czech Academy of Sciences Publication Activity Database

    Marková, Silvia; Dufresne, F.; Rees, D. J.; Černý, M.; Kotlík, Petr

    2007-01-01

    Roč. 44, - (2007), s. 42-52 ISSN 1055-7903 Grant - others:Grant Agency of Charles University(CZ) 197/2004-2005 Institutional research plan: CEZ:AV0Z50450515 Keywords : arctic * colonization * Daphnia pulex complex Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.994, year: 2007

  12. Characterization of the secretomes of two vibrios pathogenic to mollusks.

    Directory of Open Access Journals (Sweden)

    Stéphanie Madec

    Full Text Available Vibrio tapetis causes the brown ring disease in the Japanese clam Ruditapes philippinarum while Vibrio aestuarianus is associated with massive oyster mortalities. As extracellular proteins are often associated with the virulence of pathogenic bacteria, we undertook a proteomic approach to characterize the secretomes of both vibrios. The extracellular proteins (ECPs of both species were fractionated by SEC-FPLC and in vitro assays were performed to measure the effects of each fraction on hemocyte cellular parameters (phagocytosis and adhesion. Fractions showing a significant effect were subjected to SDS-PAGE, and proteins were identified by nano LC-MS/MS. 45 proteins were identified for V. aestuarianus and 87 for V. tapetis. Most of them belonged to outer membrane or were periplasmic, including porins or adhesins that were already described as virulence factors in other bacterial species. Others were transporter components, flagella proteins, or proteins of unknown function (14 and 15 respectively. Interestingly, for V. aestuarianus, we noted the secretion of 3 extracellular enzymes including the Vam metalloprotease and two other enzymes (one putative lipase and one protease. For V. tapetis, we identified five extracellular enymes, i.e. two different endochitinases, one protease, one lipase and an adhesin. A comparison of both secretomes also showed that only the putative extracellular lipase was common to both secretomes, underscoring the difference in pathogenicity mechanisms between these two species. Overall, these results characterize for the first time the secretomes of these two marine pathogenic vibrios and constitute a useful working basis to further analyze the contribution of specific proteins in the virulence mechanisms of these species.

  13. gfp-based N-acyl homoserine-lactone sensor systems for detection of bacterial communication

    DEFF Research Database (Denmark)

    Andersen, Jens Bo; Heydorn, Arne; Hentzer, Morten

    2001-01-01

    In order to perform single-cell analysis and online studies of N-acyl homoserine lactone (AHL)-mediated communication among bacteria, components of the Vibrio fischeri quorum sensor encoded by luxR-P-luxI have been fused to modified versions of gfpmut3* genes encoding unstable green fluorescent...... proteins. Bacterial strains harboring this green fluorescent sensor detected a broad spectrum of AHL molecules and were capable of sensing the presence of 5 nM N-3-oxohexanoyl-L-homoserine lactone in the surroundings. In combination with epifluorescent microscopy, the sensitivity of the sensor enabled AHL...

  14. The Emergence of Vibrio pathogens in Europe: Ecology, Evolution and Pathogenesis (Paris, 11-12 March 2015

    Directory of Open Access Journals (Sweden)

    Frederique eLe Roux

    2015-08-01

    Full Text Available Global change has caused a worldwide increase in reports of Vibrio-associated diseases with ecosystem-wide impacts on humans and marine animals. In Europe, higher prevalence of human infections followed regional climatic trends with outbreaks occurring during episodes of unusually warm weather. Similar patterns were also observed in Vibrio-associated diseases affecting marine organisms such as fish, bivalves and corals. Basic knowledge is still lacking on the ecology and evolutionary biology of these bacteria as well as on their virulence mechanisms. Current limitations in experimental systems to study infection and the lack of diagnostic tools still prevent a better understanding of Vibrio emergence. A major challenge is to foster cooperation between fundamental and applied research in order to investigate the consequences of pathogen emergence in natural Vibrio populations and answer federative questions that meet societal needs. Here we report the proceedings of the first European workshop dedicated to these specific goals of the Vibrio research community by connecting current knowledge to societal issues related to ocean health and food security.

  15. Multigenerational contaminant exposures produce non-monotonic, transgenerational responses in Daphnia magna

    International Nuclear Information System (INIS)

    Kimberly, David A.; Salice, Christopher J.

    2015-01-01

    Generally, ecotoxicologists rely on short-term tests that assume populations to be static. Conversely, natural populations may be exposed to the same stressors for many generations, which can alter tolerance to the same (or other) stressors. The objective of this study was to improve our understanding of how multigenerational stressors alter life history traits and stressor tolerance. After continuously exposing Daphnia magna to cadmium for 120 days, we assessed life history traits and conducted a challenge at higher temperature and cadmium concentrations. Predictably, individuals exposed to cadmium showed an overall decrease in reproductive output compared to controls. Interestingly, control D. magna were the most cadmium tolerant to novel cadmium, followed by those exposed to high cadmium. Our data suggest that long-term exposure to cadmium alter tolerance traits in a non-monotonic way. Because we observed effects after one-generation removal from cadmium, transgenerational effects may be possible as a result of multigenerational exposure. - Highlights: • Daphnia magna exposed to cadmium for 120 days. • D. magna exposed to cadmium had decreased reproductive output. • Control D. magna were most cadmium tolerant to novel cadmium stress. • Long-term exposure to cadmium alter tolerance traits in a non-monotonic way. • Transgenerational effects observed as a result of multigenerational exposure. - Adverse effects of long-term cadmium exposure persist into cadmium free conditions, as seen by non-monotonic responses when exposed to novel stress one generation removed.

  16. Comet Assay on Daphnia magna in eco-genotoxicity testing.

    Science.gov (United States)

    Pellegri, Valerio; Gorbi, Gessica; Buschini, Annamaria

    2014-10-01

    Detection of potentially hazardous compounds in water bodies is a priority in environmental risk assessment. For the evaluation and monitoring of water quality, a series of methodologies may be applied. Among them, the worldwide used toxicity tests with organisms of the genus Daphnia is one of the most powerful. In recent years, some attempts were made to utilize Daphnia magna in genotoxicity testing as many of the new environmental contaminants are described as DNA-damaging agents in aquatic organisms. The aim of this research was to develop a highly standardized protocol of the Comet Assay adapted for D. magna, especially regarding the isolation of cells derived from the same tissue (haemolymph) from newborn organisms exposed in vivo. Several methods for haemolymph extraction and different Comet Assay parameters were compared. Electrophoretic conditions were adapted in order to obtain minimum DNA migration in cells derived from untreated organisms and, at the same time, maximum sensitivity in specimens treated with known genotoxicants (CdCl2 and H2O2). Additional tests were performed to investigate if life-history traits of the cladoceran (such as the age of adult organisms that provide newborns, the clutch size of origin, the number of generations reared in standard conditions) and the water composition as well, might influence the response of the assay. This study confirms the potential application of the Comet Assay in D. magna for assessing genotoxic loads in aqueous solution. The newly developed protocol could integrate the acute toxicity bioassay, thus expanding the possibility of using this model species in freshwater monitoring (waters, sediment and soil elutriates) and is in line with the spirit of the EU Water Framework Directive in reducing the number of bioassays that involve medium-sized species. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Review on the acute Daphnia magna toxicity test – Evaluation of the sensitivity and the precision of assays performed with organisms from laboratory cultures or hatched from dormant eggs

    Directory of Open Access Journals (Sweden)

    Persoone G.

    2009-08-01

    Daphnias taken from lab cultures or with Daphnia microbiotests are within the acceptability range set by ISO standard 6341 for the reference chemical potassium dichromate. (2 The mean 24 h EC50s of the Daphnia microbiotests performed in different laboratories are within the range of the mean EC50s of the assays based on lab cultures, and the variation coefficients (20 to 30% are similar. (3 The precision – in terms of the long term in house variability – of the quality control Daphnia microbiotests is as good as that of the QC tests based on lab cultures. The review further reports on intra-laboratory sensitivity comparison studies performed during the last 15 years on pure chemicals and on natural samples, with both laboratory cultured organisms and Daphnias hatched from dormant eggs. These studies carried out in different laboratories showed EC50 correlation coefficients of 0.86 to 0.98, corroborating a similar sensitivity of the two types of test organisms. The third part of the review reports and analyses data on proficiency ringtests on the acute D. magna assay which have been organised in different countries since 2002 with either reference chemicals or with natural samples, and in which part of the laboratories performed their assays with Daphnia microbiotests and others with lab cultured Daphnias. The conclusions drawn from all the ringtests indicate that the sensitivity of Daphnia neonates hatched from dormant eggs is similar to that of test organisms taken from lab cultures and that in most cases the precision of the Daphnia microbiotest is superior to that of the assays based on lab cultures. The review finally addresses the issue of possible sensitivity differences of Daphnias hatched from dormant eggs which are produced by different D. magna strains. From these investigations it appeared that the EC50s from assays performed with Daphnias hatched from dormant eggs of different strains did not differ significantly from those from assays undertaken with

  18. Food chain effects of sublethal ultraviolet radiation on subarctic .i.Daphnia pulex./i. - a field and laboratory study

    Czech Academy of Sciences Publication Activity Database

    Zellmer, I.D.; Arts, M.T.; Šustr, Vladimír

    2006-01-01

    Roč. 167, 1-4 (2006), s. 515-531 ISSN 0003-9136 Institutional research plan: CEZ:AV0Z6066911 Keywords : UV radiation * Daphnia * enzymes Subject RIV: EH - Ecology, Behaviour Impact factor: 1.362, year: 2006

  19. Extract from the fermented soybean product Natto inhibits Vibrio biofilm formation and reduces shrimp mortality from Vibrio harveyi infection.

    Science.gov (United States)

    Yatip, Pattanan; Nitin Chandra Teja, D; Flegel, Timothy W; Soowannayan, Chumporn

    2018-01-01

    Many bacteria, including Vibrio pathogens of shrimp, need to colonize and/or form biofilms in hosts or the environment to cause disease. Thus, one possible control strategy for shrimp Vibriosis is biofilm inhibition. With this objective, an extract from the Japanese fermented soybean product, Natto was tested with the luminescent shrimp pathogen Vibrio harveyi (VH) for its ability to inhibit or degrade biofilm and to interfere with cell growth in broth. Natto is a traditional fermentation product of Bacillus subtilis var Natto (BSN1). Using 96 well microtiter plates coated with 0.4% chitosan, we found that biofilm formation by VH was inhibited, while growth in parallel broth cultures was not. When an extract from Natto prepared using BSN1 was mixed with feed for the whiteleg shrimp Penaeus vannamei before immersion challenge with V. harveyi at 10 6  cfu/ml, survival was significantly higher (p≤0.05) than for control shrimp given feed without these additives. Further work done to test whether d-amino acids were involved in biofilm formation as previously reported for B. subtilis, Staphylococus aureus and Pseudomonas aeruginosa gave negative results. In conclusion, we discovered that Natto extract can inhibit Vibrio biofilm formation and that it or BSN1 alone added to shrimp feed can significantly reduce shrimp mortality in immersion challenges with pathogenic VH. This shows some promise for possible application against Vibriosis in shrimp since Natto is generally regarded as safe (GRAS) for human consumption. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Investigating the formation and toxicity of nitrogen transformation products of diclofenac and sulfamethoxazole in wastewater treatment plants

    International Nuclear Information System (INIS)

    Osorio, Victoria; Sanchís, Josep; Abad, Jose Luís; Ginebreda, Antoni; Farré, Marinella; Pérez, Sandra; Barceló, Damià

    2016-01-01

    Highlights: • Environmental monitoring of recently discovered TPs of diclofenac in wastewater and surface water. • Quantitative determination of non-detected TPs of sulfamethoxazole in wastewater and impacted surface waters. • Toxicity assessment of diclofenac and its TPs in a panel of standard assays of aquatic organism. • Only nitro-diclofenac proved to be more toxic than the parent compound. - Abstract: Diclofenac (DCF) and sulfamethoxazole (SMX) are highly consumed pharmaceuticals and concentrated in effluents from conventional wastewater treatment plants (WWTPs) since they are not completely eliminated. Under microbial mediated nitrification/denitrification processes occurring in nitrifying activated sludge DCF biotransformed into its nitroso and nitro derivatives (NO-DCF and NO 2 -DCF, respectively). SMX was biotransformed under denitrification conditions in water/sediment batch reactors into its nitro and desamino derivatives (NO 2 -SMX and Des-SMX, respectively). Four transformation products (TPs) from DCF and SMX were analized in wastewaters (WW) and receiving surface waters (SW). Nitrifying/denitrifying-derivatives of DCF and SMX were detected for the first time in WW and SW at one order of magnitude lower than their parent compounds. Relationships observed among levels of NO-DCF, NO 2 -DCF and nitrogen-species tentatively suggested that nitrification/denitrification processes are involved in nitration and nitrosation of DCF during biological WW treatment. Acute toxicity of analytes to Daphnia magna and Vibrio fischeri was assessed individually and in mixtures with other relevant micropollutants. Individual effects showed these compounds as not harmful and not toxic. However, synergism effects observed in mixtures evidenced that contribution of these compounds to overall toxicity of complex environmental samples, should not be dismissed.

  1. Ketoprofen removal by O3 and O3/UV processes: Kinetics, transformation products and ecotoxicity

    International Nuclear Information System (INIS)

    Illés, Erzsébet; Szabó, Emese; Takács, Erzsébet; Wojnárovits, László; Dombi, András; Gajda-Schrantz, Krisztina

    2014-01-01

    Ozonation (O 3 ) and its combination with ultraviolet radiation (O 3 /UV) were used to decompose ketoprofen (KET). Depending on the initial KET concentration, fourteen to fifty time's faster KET degradation was achieved using combined O 3 /UV method compared to simple ozonation. Using both methods, formation of four major aromatic transformation products were observed: 3-(1-hydroxyethyl)benzophenone, 3-(1-hydroperoxyethyl) benzophenone, 1-(3-benzoylphenyl) ethanone and 3-ethylbenzophenone. In the combined treatment the degradation was mainly due to the direct effect of UV light, however, towards the end of the treatment, O 3 highly contributed to the mineralization of small carboxylic acids. High (∼ 90%) mineralization degree was achieved using the O 3 /UV method. Toxicity tests performed using representatives of three trophic levels of the aquatic ecosystems (producers, consumers and decomposers) Pseudokirchneriella subcapitata green algae, Daphnia magna zooplanktons and Vibrio fischeri bacteria showed that under the used experimental conditions the transformation products have significantly higher toxicity towards all the test organisms, than KET itself. The bacteria and the zooplanktons showed higher tolerance to the formed products than algae. The measured toxicity correlates well with the concentration of the aromatic transformation products, therefore longer treatments than needed for complete degradation of KET are strongly suggested, in order to avoid possible impact of aromatic transformation products on the aquatic ecosystem. - Highlights: • Ketoprofen degradation is significantly faster using O 3 /UV compared to ozonation. • The presence of O 3 enhances the overall mineralization. • Formation of four major aromatic by-products was observed. • The main step in the decomposition is the decarboxylation. • Degradation products have higher toxicity than ketoprofen itself

  2. Ecotoxicological characterization of polyoxyethylene glycerol ester non-ionic surfactants and their mixtures with anionic and non-ionic surfactants.

    Science.gov (United States)

    Ríos, Francisco; Fernández-Arteaga, Alejandro; Lechuga, Manuela; Fernández-Serrano, Mercedes

    2017-04-01

    This paper reports on a study that investigated the aquatic toxicity of new non-ionic surfactants derived from renewable raw materials, polyoxyethylene glycerol ester (PGE), and their binary mixtures with anionic and non-ionic surfactants. Toxicity of pure PGEs was determined using representative organisms from different trophic levels: luminescent bacteria (Vibrio fischeri), microalgae (Pseudokirchneriella subcapitata), and freshwater crustaceans (Daphnia magna). Relationships between toxicity and the structural parameters such as unit of ethylene oxide (EO) and hydrophilic-lipophilic balance (HLB) were evaluated. Critical micellar concentration (CMC) in the conditions of the toxicity test was also determined. It was found that the toxicity of the aqueous solutions of PGE decreased when the number of EO units in the molecule, HLB, and CMC increased. PGEs showed lower CMC in marine medium, and the toxicity to V. ficheri is lower when the CMC was higher. Given their non-polar nature, narcosis was expected to be the primary mode of toxic action of PGEs. For the mixture of surfactants, we observed that the mixtures with PGE that had the higher numbers of EO units were more toxic than the aqueous solutions of pure surfactants. Moreover, we found that concentration addition was the type of action more likely to occur for mixtures of PGE with lower numbers of EO units with non-ionic surfactants (alkylpolyglucoside and fatty alcohol ethoxylate), whereas for the mixture of PGE with lower EO units and anionic surfactant (ether carboxylic derivative), the most common response type was response addition. In case of mixtures involving amphoteric surfactants and PGEs with the higher numbers of EO units, no clear pattern with regard to the mixture toxicity response type could be observed.

  3. Development of sensitive and reliable LC-MS/MS methods for the determination of three fluoroquinolones in water and fish tissue samples and preliminary environmental risk assessment of their presence in two rivers in northern Poland.

    Science.gov (United States)

    Wagil, Marta; Kumirska, Jolanta; Stolte, Stefan; Puckowski, Alan; Maszkowska, Joanna; Stepnowski, Piotr; Białk-Bielińska, Anna

    2014-09-15

    Antibiotic consumption (e.g. fluoroquinolones (FQs)) and, as a consequence, their presence in the environment, have received a lot of attention in the last several years due to increasing numbers of diseases and infections that are becoming resistant to traditional treatments for both humans and animals. In addition, even though antibiotics are safe for human and veterinary usage, ecosystems may be exposed to these substances. In this study, analytical methods for determining enrofloxacin (ENR), norfloxacin (NOR) and ciprofloxacin (CIP) in water samples and fish tissue based on the LC-MS/MS technique were developed and validated. As there is no data available concerning the risks posed by antibiotics in Poland, the proposed methods were applied for monitoring drug presence in environmental samples collected from two rivers in northern Poland. Evaluations of the ecotoxicity of ENR, NOR and CIP towards four different species of aquatic organisms: marine bacteria (Vibrio fischeri), green algae (Scenedesmus vacuolatus), duckweed (Lemna minor) and crustacean (Daphnia magna), were also carried out. All the investigated compounds were detected at least once in the survey. NOR was found to be the most ubiquitous drug with concentrations of up to 442.8 ng L(-1). Moreover, it was established that L. minor is the most sensitive species to the investigated drugs (EC50NOR = 0.13 mg L(-1), EC50ENR = 0.22 mg L(-1) and EC50CIP = 0.34 mg L(-1)). The calculated risk quotient (RQ) values confirmed that the concentrations of the investigated FQs in the environmental samples were at a level of moderate environmental risk (1environmental risk (RQCIP = 8.1). Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Investigating the formation and toxicity of nitrogen transformation products of diclofenac and sulfamethoxazole in wastewater treatment plants

    Energy Technology Data Exchange (ETDEWEB)

    Osorio, Victoria; Sanchís, Josep [Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona (Spain); Abad, Jose Luís [RUBAM-IIQAC-CSIC, Jordi Girona 18-26, Barcelona (Spain); Ginebreda, Antoni; Farré, Marinella [Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona (Spain); Pérez, Sandra, E-mail: spsqam@idaea.csic.es [Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona (Spain); Barceló, Damià [Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona (Spain); Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Emili Grahit 101, Girona (Spain)

    2016-05-15

    Highlights: • Environmental monitoring of recently discovered TPs of diclofenac in wastewater and surface water. • Quantitative determination of non-detected TPs of sulfamethoxazole in wastewater and impacted surface waters. • Toxicity assessment of diclofenac and its TPs in a panel of standard assays of aquatic organism. • Only nitro-diclofenac proved to be more toxic than the parent compound. - Abstract: Diclofenac (DCF) and sulfamethoxazole (SMX) are highly consumed pharmaceuticals and concentrated in effluents from conventional wastewater treatment plants (WWTPs) since they are not completely eliminated. Under microbial mediated nitrification/denitrification processes occurring in nitrifying activated sludge DCF biotransformed into its nitroso and nitro derivatives (NO-DCF and NO{sub 2}-DCF, respectively). SMX was biotransformed under denitrification conditions in water/sediment batch reactors into its nitro and desamino derivatives (NO{sub 2}-SMX and Des-SMX, respectively). Four transformation products (TPs) from DCF and SMX were analized in wastewaters (WW) and receiving surface waters (SW). Nitrifying/denitrifying-derivatives of DCF and SMX were detected for the first time in WW and SW at one order of magnitude lower than their parent compounds. Relationships observed among levels of NO-DCF, NO{sub 2}-DCF and nitrogen-species tentatively suggested that nitrification/denitrification processes are involved in nitration and nitrosation of DCF during biological WW treatment. Acute toxicity of analytes to Daphnia magna and Vibrio fischeri was assessed individually and in mixtures with other relevant micropollutants. Individual effects showed these compounds as not harmful and not toxic. However, synergism effects observed in mixtures evidenced that contribution of these compounds to overall toxicity of complex environmental samples, should not be dismissed.

  5. Application of a battery of biotests for the determination of leachate toxicity to bacteria and invertebrates from sewage sludge-amended soil.

    Science.gov (United States)

    Malara, Anna; Oleszczuk, Patryk

    2013-05-01

    The objective of the study was to determine the leachates toxicity from sewage sludge-amended soils (sandy and loamy). Samples originated from a plot experiment realized over a period of 29 months. Two types of soil were fertilized with sewage sludges at the dose of 3 % (90 t/ha). Soil samples were taken after 0, 7, 17, and 29 months from the application of sewage sludges. Leachates were obtained according to the EN 12457-2 protocol. The following commercial tests were applied for the estimation of the toxicity: Microtox (Vibrio fischeri), Microbial assay for toxic risk assessment (ten bacteria and one yeast), Protoxkit F (Tetrahymena thermophila), Rotoxkit F (Brachionus calyciflorus), and Daphtoxkit F (Daphnia magna). The test organisms displayed varied toxicity with relation to the soils amended with sewage sludges. The toxicity of the leachates depended both on the soil type and on the kind of sewage sludge applied. Notable differences were also observed in the sensitivity of the test organisms to the presence of sewage sludge in the soil. The highest sensitivity was a characteristic of B. calyciflorus, while the lowest sensitivity to the presence of the sludges was revealed by the protozoa T. thermophila. Throughout the periods of the study, constant variations of toxicity were observed for most of the test organisms. The intensity as well as the range of those variations depended both on the kind of test organism and on the kind of sludge and soil type. In most cases, an increase of the toxicity of soils amended with the sewage sludges was observed after 29 months of the experiment.

  6. Effects of chlorpyrifos on individuals and populations of Daphnia pulex in the laboratory and field

    NARCIS (Netherlands)

    Hoeven, N. van der; Gerritsen, A.A.M.

    1997-01-01

    Effects of the insecticide chlorpyrifos (cpf) on young (Daphnia pulex and the ability of D. pulex to recover after exposure were tested in the laboratory. Populations of D. pulex exposed to cpf were studied in the laboratory and field. In the field, cpf was applied in

  7. Identification of capsule, biofilm, lateral flagellum, and type IV pili in Vibrio mimicus strains.

    Science.gov (United States)

    Tercero-Alburo, J J; González-Márquez, H; Bonilla-González, E; Quiñones-Ramírez, E I; Vázquez-Salinas, C

    2014-11-01

    Vibrio mimicus is a bacterium that causes gastroenteritis; it is closely related to Vibrio cholerae, and can cause acute diarrhea like cholera- or dysentery-type diarrhea. It is distributed worldwide. Factors associated with virulence (such as hemolysins, enterotoxins, proteases, phospholipases, aerobactin, and hemagglutinin) have been identified; however, its pathogenicity mechanism is still unknown. In pathogenic Vibrio species such as V. cholerae, Vibrio. parahaemolyticus and Vibrio vulnificus, capsule, biofilms, lateral flagellum, and type IV pili are structures described as essential for pathogenicity. These structures had not been described in V. mimicus until this work. We used 20 V. mimicus strains isolated from water (6), oyster (9), and fish (5) samples and we were able to identify the capsule, biofilm, lateral flagellum, and type IV pili through phenotypic tests, electron microscopy, PCR, and sequencing. In all tested strains, we observed and identified the presence of capsular exopolysaccharide, biofilm formation in an in vitro model, as well as swarming, multiple flagellation, and pili. In addition, we identified homologous genes to those described in other bacteria of the genus in which these structures have been found. Identification of these structures in V. mimicus is a contribution to the biology of this organism and can help to reveal its pathogenic behavior. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Vibrio parahemolyticus bacteremia: case report.

    Science.gov (United States)

    Ng, T C; Chiang, P C; Wu, T L; Leu, H S

    1999-09-01

    Vibrio parahemolyticus (V. parahemolyticus) is a halophilic gram-negative bacillus that lives in the ocean. It is the leading cause of infectious diarrhea in Taiwan and sometimes produces soft tissue infections, but it is rarely a cause of bacteremia. There have been only 11 cases reported in the literature. Most of the cases involved a history of ingestion of seafood or exposure to seawater. In addition, those patients were all immunosuppressed, especially with leukemia and cirrhosis. We report a 60-year-old male patient with chronic hepatitis C and adrenal insufficiency. He developed V. parahemolyticus bacteremia following ingestion of seafood one week prior to admission. His condition was complicated with neck and right lower leg soft tissue infection, as well as multiple organ failure. The patient survived after intravenous ceftazidime, oral doxycycline, and surgical debridement. To our knowledge, this is the 12th reported cases on Medline, and the second bacteremic case in Taiwan. After reviewing the literature, we suggest that all patients with immunosuppressed conditions or adrenal insufficiency should eat foods that are well cooked and avoid raw seafood. Moreover, when patients who are at risk to develop fever, diarrhea, and soft tissue infection after ingestion of seafood, V. parahemolyticus infection should be suspected. All culture specimens should be inoculated on Vibrios selective media.

  9. Ecotoxicity of binary mixtures of Microcystis aeruginosa and insecticides to Daphnia pulex

    International Nuclear Information System (INIS)

    Asselman, J.; Janssen, C.R.; Smagghe, G.; De Schamphelaere, K.A.C.

    2014-01-01

    In aquatic ecosystems, mixtures of chemical and natural stressors can occur which may significantly complicate risk assessment approaches. Here, we show that effects of binary combinations of four different insecticides and Microcystis aeruginosa, a toxic cyanobacteria, on Daphnia pulex exhibited distinct interaction patterns. Combinations with chlorpyrifos and tetradifon caused non-interactive effects, tebufenpyrad caused an antagonistic interaction and fenoyxcarb yielded patterns that depended on the reference model used (i.e. synergistic with independent action, additive with concentration addition). Our results demonstrate that interactive effects cannot be generalised across different insecticides, not even for those targeting the same biological pathway (i.e. tebufenpyrad and tetradifon both target oxidative phosphorylation). Also, the concentration addition reference model provided conservative predictions of effects in all investigated combinations for risk assessment. These predictions could, in absence of a full mechanistic understanding, provide a meaningful solution for managing water quality in systems impacted by both insecticides and cyanobacterial blooms. - Highlights:: • 2 of 4 insecticide-Microcystis combinations showed no interactive effect on Daphnia. • One insecticide showed antagonistic deviation patterns. • For one other insecticide the results depended on the reference model used. • Interactive effects between insecticides and Microcystis cannot be generalized. • The concentration addition model provides conservative estimates of mixture effects. - Interactive effects between insecticides and cyanobacterial stressors cannot be generalized, not even for insecticides with closely related known modes of action

  10. Isolation and molecular identification of Vibrio spp. by sequencing of 16S rDNA from seafood, meat and meat products in Libya

    Science.gov (United States)

    Azwai, S.M.; Alfallani, E.A.; Abolghait, S.K.; Garbaj, A.M.; Naas, H.T.; Moawad, A.A.; Gammoudi, F.T.; Rayes, H.M.; Barbieri, I.; Eldaghayes, I.M.

    2016-01-01

    The genus Vibrio includes several food-borne pathogens that cause a spectrum of clinical conditions including septicemia, cholera and milder forms of gastroenteritis. Several Vibrio spp. are commonly associated with food-borne transmission including Vibrio cholerae, Vibrio parahemolyticus, and Vibrio vulnificus. Microbiological analysis for enumeration and isolation of Vibrio spp. were carried out for a total of 93 samples of seafood, meat and meat products from different geographic localities in Libya (Tripoli, Regdalin, Janzour and Tobruk). Vibrio spp. were detected by conventional cultural and molecular method using PCR and sequencing of 16S rDNA. Out of the 93 cultured samples only 48 (51.6%) yielded colonies on Thiosulfate Citrate Bile Salt agar (TCBS) with culture characteristics of Vibrio spp. More than half (n=27) of processed seafood samples (n=46) yielded colonies on TCBS, while only 44.6 % of samples of meat and meat products showed colonies on TCBS. Among cultured seafood samples, the highest bacterial count was recorded in clam with a count of 3.8 ×104 CFU\\g. Chicken burger samples showed the highest bacterial count with 6.5 ×104 CFU\\g. Molecular analysis of the isolates obtained in this study, showed that 11 samples out of 48 (22.9%) were Vibrio spp. Vibrio parahemolyticus was isolated from camel meat for the first time. This study is an initial step to provide a baseline for future molecular research targeting Vibrio spp. foodborne illnesses. This data will be used to provide information on the magnitude of such pathogens in Libyan seafood, meat and meat products. PMID:27004169

  11. Isolation and molecular identification of Vibrio spp. by sequencing of 16S rDNA from seafood, meat and meat products in Libya

    Directory of Open Access Journals (Sweden)

    S.M. Azwai

    2016-03-01

    Full Text Available The genus Vibrio includes several food-borne pathogens that cause a spectrum of clinical conditions including septicemia, cholera and milder forms of gastroenteritis. Several Vibrio spp. are commonly associated with food-borne transmission including Vibrio cholerae, Vibrio parahemolyticus, and Vibrio vulnificus. Microbiological analysis for enumeration and isolation of Vibrio spp. were carried out for a total of 93 samples of seafood, meat and meat products from different geographic localities in Libya (Tripoli, Regdalin, Janzour and Tobruk. Vibrio spp. were detected by conventional cultural and molecular method using PCR and sequencing of 16S rDNA. Out of the 93 cultured samples only 48 (51.6% yielded colonies on Thiosulfate Citrate Bile Salt agar (TCBS with culture characteristics of Vibrio spp. More than half (n=27 of processed seafood samples (n=46 yielded colonies on TCBS, while only 44.6% of samples of meat and meat products showed colonies on TCBS. Among cultured seafood samples, the highest bacterial count was recorded in clam with a count of 3.8 х104 CFU\\g. Chicken burger samples showed the highest bacterial count with 6.5 х104 CFU\\g. Molecular analysis of the isolates obtained in this study, showed that 11 samples out of 48 (22.9% were Vibrio spp. Vibrio parahemolyticus was isolated from camel meat for the first time. This study is an initial step to provide a baseline for future molecular research targeting Vibrio spp. foodborne illnesses. This data will be used to provide information on the magnitude of such pathogens in Libyan seafood, meat and meat products.

  12. Isolation and molecular identification of Vibrio spp. by sequencing of 16S rDNA from seafood, meat and meat products in Libya.

    Science.gov (United States)

    Azwai, S M; Alfallani, E A; Abolghait, S K; Garbaj, A M; Naas, H T; Moawad, A A; Gammoudi, F T; Rayes, H M; Barbieri, I; Eldaghayes, I M

    2016-01-01

    The genus Vibrio includes several food-borne pathogens that cause a spectrum of clinical conditions including septicemia, cholera and milder forms of gastroenteritis. Several Vibrio spp. are commonly associated with food-borne transmission including Vibrio cholerae, Vibrio parahemolyticus, and Vibrio vulnificus. Microbiological analysis for enumeration and isolation of Vibrio spp. were carried out for a total of 93 samples of seafood, meat and meat products from different geographic localities in Libya (Tripoli, Regdalin, Janzour and Tobruk). Vibrio spp. were detected by conventional cultural and molecular method using PCR and sequencing of 16S rDNA. Out of the 93 cultured samples only 48 (51.6%) yielded colonies on Thiosulfate Citrate Bile Salt agar (TCBS) with culture characteristics of Vibrio spp. More than half (n=27) of processed seafood samples (n=46) yielded colonies on TCBS, while only 44.6 % of samples of meat and meat products showed colonies on TCBS. Among cultured seafood samples, the highest bacterial count was recorded in clam with a count of 3.8 ×10(4) CFU\\g. Chicken burger samples showed the highest bacterial count with 6.5 ×10(4) CFU\\g. Molecular analysis of the isolates obtained in this study, showed that 11 samples out of 48 (22.9%) were Vibrio spp. Vibrio parahemolyticus was isolated from camel meat for the first time. This study is an initial step to provide a baseline for future molecular research targeting Vibrio spp. foodborne illnesses. This data will be used to provide information on the magnitude of such pathogens in Libyan seafood, meat and meat products.

  13. Organic metabolites produced by Vibrio parahaemolyticus strain ...

    African Journals Online (AJOL)

    Identification and action of several antibacterial metabolites produced by a fish pathogen Vibrio parahaemolyticus strain An3 from marine ecosystem of Goa has been demonstrated. Antibacterial activity of the crude cell extract of the test bacterium has been evaluated against indicator pathogenic bacterial strains such as ...

  14. Parasitism drives host genome evolution: Insights from the Pasteuria ramosa-Daphnia magna system.

    Science.gov (United States)

    Bourgeois, Yann; Roulin, Anne C; Müller, Kristina; Ebert, Dieter

    2017-04-01

    Because parasitism is thought to play a major role in shaping host genomes, it has been predicted that genomic regions associated with resistance to parasites should stand out in genome scans, revealing signals of selection above the genomic background. To test whether parasitism is indeed such a major factor in host evolution and to better understand host-parasite interaction at the molecular level, we studied genome-wide polymorphisms in 97 genotypes of the planktonic crustacean Daphnia magna originating from three localities across Europe. Daphnia magna is known to coevolve with the bacterial pathogen Pasteuria ramosa for which host genotypes (clonal lines) are either resistant or susceptible. Using association mapping, we identified two genomic regions involved in resistance to P. ramosa, one of which was already known from a previous QTL analysis. We then performed a naïve genome scan to test for signatures of positive selection and found that the two regions identified with the association mapping further stood out as outliers. Several other regions with evidence for selection were also found, but no link between these regions and phenotypic variation could be established. Our results are consistent with the hypothesis that parasitism is driving host genome evolution. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  15. Toxicity assessment of polluted sediments using swimming behavior alteration test with Daphnia magna

    Science.gov (United States)

    Nikitin, O. V.; Nasyrova, E. I.; Nuriakhmetova, V. R.; Stepanova, N. Yu; Danilova, N. V.; Latypova, V. Z.

    2018-01-01

    Recently behavioral responses of organisms are increasingly used as a reliable and sensitive tool in aquatic toxicology. Behavior-related endpoints allow efficiently studying the effects of sub-lethal exposure to contaminants. At present behavioural parameters frequently are determined with the use of digital analysis of video recording by computer vision technology. However, most studies evaluate the toxicity of aqueous solutions. Due to methodological difficulties associated with sample preparation not a lot of examples of the studies related to the assessment of toxicity of other environmental objects (wastes, sewage sludges, soils, sediments etc.) by computer vision technology. This paper presents the results of assessment of the swimming behavior alterations of Daphnia magna in elutriates from both uncontaminated natural and artificially chromium-contaminated bottom sediments. It was shown, that in elutriate from chromium contaminated bottom sediments (chromium concentration 115±5.7 μg l-1) the swimming speed of daphnids was decreases from 0.61 cm s-1 (median speed over the period) to 0.50 cm s-1 (median speed at the last minute of the experiment). The relocation of Daphnia from the culture medium to the extract from the non-polluted sediments does not essential changes the swimming activity.

  16. Contamination of community water sources by potentially pathogenic vibrios following sea water inundation.

    Science.gov (United States)

    Kanungo, Reba; Shashikala; Karunasagar, I; Srinivasan, S; Sheela, Devi; Venkatesh, K; Anitha, P

    2007-12-01

    Potentially pathogenic members of the Vibrionaceae family including Vibrio cholerae and Vibrio parahemolyticus were isolated from domestic sources of drinking water in coastal villages following sea water inundation during the tsunami in Southern India. Phenotypic and genotypic studies were done to confirm the identity and detection of toxins. Vibrio-gyr (gyrase B gene) was detected in all sixteen vibrio isolates. Toxin regulating genes i.e.: ctx gene, tdh gene, and trh gene, however were not detected in any of the strains, thereby ruling out presence of toxins which could endanger human life. Other potentially pathogenic bacteria Aeromonas and Plesiomonas were also isolated from hand pumps and wells, in a few localities. There was no immediate danger in the form of an outbreak or sporadic gastroenteritis at the time of the study. Timely chlorination and restoration of potable water supply to the flood affected population by governmental and nongovernmental agencies averted waterborne gastroenteritis. Assessment of quality of water and detection of potential virulent organisms is an important public health activity following natural disasters. This work highlights the importance of screening water sources for potentially pathogenic microorganisms after natural disasters to avert outbreaks of gastroenteritis and other infectious diseases.

  17. Investigating the decay rates of Escherichia coli relative to Vibrio parahemolyticus and Salmonella Typhi in tropical coastal waters.

    Science.gov (United States)

    Lee, Choon Weng; Ng, Angie Yee Fang; Bong, Chui Wei; Narayanan, Kumaran; Sim, Edmund Ui Hang; Ng, Ching Ching

    2011-02-01

    Using the size fractionation method, we measured the decay rates of Escherichia coli, Salmonella Typhi and Vibrio parahaemolyticus in the coastal waters of Peninsular Malaysia. The size fractions were total or unfiltered, 0.7 μm) than in the smaller fraction (Vibrio grew well in seawater. There was usually an increase in Vibrio after one day incubation. Our results confirmed that decay or loss rates of E. coli did not match that of Vibrio, and also did not correlate with Salmonella decay rates. However E. coli showed persistence where its decay rates were generally lower than Salmonella. © 2010 Elsevier Ltd. All rights reserved.

  18. Identification of DLD, by immunoproteomic analysis and evaluation as a potential vaccine antigen against three Vibrio species in Epinephelus coioides.

    Science.gov (United States)

    Pang, Huanying; Chen, Liming; Hoare, Rowena; Huang, Yucong; ZaoheWu; Jian, Jichang

    2016-02-24

    Vibrio spp. represent a serious threat to the culture of Epinephelus coioides (Orange-spotted Grouper) in Southeast Asia. In this study we used two-dimensional electrophoresis (2-DE) and Western blotting to identify common immunogenic proteins of Vibrio alginolyticus, Vibrio harveyi and Vibrio parahaemolyticus. Membranes were probed with orange-spotted grouper anti-V. alginolyticus sera and accordingly 60, 58 and 48 immunogenic protein spots were detected. By matching analysis for the three Western blotting membranes, 6 cross immunogenic spots for the three Vibrio species were identified. They were Outer membrane protein W (OmpW), dihydrolipoamide dehydrogenase (DLD), succinate dehydrogenase flavoprotein subunit(SDHA), elongation factor Ts(Ts), peptide ABC transporter periplasmic peptide-binding protein and phosphoenolpyruvate carboxykinase(PEPCK). One of the proteins, DLD, was used to evaluate the cross protective function for E. coioides with a bacterial immunization and challenge method. The relative percent survival rate of E. coioides against V. alginolyticus, V. harveyi and V. parahaemolyticus was 90%, 86% and 80%, respectively. This work may provide potential cross protective vaccine candidate antigens for three Vibrio species, and DLD may be considered as an effective cross-protective immunogen against three Vibrio species. Copyright © 2016. Published by Elsevier Ltd.

  19. The good, the bad and the plenty: interactive effects of food quality and quantity on the growth of different Daphnia species.

    Science.gov (United States)

    Bukovinszky, Tibor; Verschoor, Antonie M; Helmsing, Nico R; Bezemer, T Martijn; Bakker, Elisabeth S; Vos, Matthijs; de Senerpont Domis, Lisette N

    2012-01-01

    Effects of food quality and quantity on consumers are neither independent nor interchangeable. Although consumer growth and reproduction show strong variation in relation to both food quality and quantity, the effects of food quality or food quantity have usually been studied in isolation. In two experiments, we studied the growth and reproduction in three filter-feeding freshwater zooplankton species, i.e. Daphnia galeata x hyalina, D. pulicaria and D. magna, on their algal food (Scenedesmus obliquus), varying in carbon to phosphorus (C∶P) ratios and quantities (concentrations). In the first experiment, we found a strong positive effect of the phosphorus content of food on growth of Daphnia, both in their early and late juvenile development. Variation in the relationship between the P-content of animals and their growth rate reflected interspecific differences in nutrient requirements. Although growth rates typically decreased as development neared maturation, this did not affect these species-specific couplings between growth rate and Daphnia P-content. In the second experiment, we examined the effects of food quality on Daphnia growth at different levels of food quantity. With the same decrease in P-content of food, species with higher estimated P-content at zero growth showed a larger increase in threshold food concentrations (i.e. food concentration sufficient to meet metabolic requirements but not growth). These results suggest that physiological processes such as maintenance and growth may in combination explain effects of food quality and quantity on consumers. Our study shows that differences in response to variation in food quality and quantity exist between species. As a consequence, species-specific effects of food quality on consumer growth will also determine how species deal with varying food levels, which has implications for resource-consumer interactions.

  20. Antagonistic effect of Pseudomonas aeruginosa isolates from various ecological niches on Vibrio species pathogenic to crustaceans

    Institute of Scientific and Technical Information of China (English)

    Prabhakaran Priyaja; Puthumana Jayesh; Neil Scolastin Correya; Balachandran Sreelakshmi; Naduthalmuriparambil S Sudheer; Rosamma Philip; Isaac Sarogeni Bright Singh

    2014-01-01

    Objective: To abrogate pathogenic vibrios in aquaculture by testing the potential of Pseudomonas isolates from fresh water, brackish and marine environments as probiotics.Methods:Antagonistic activity of the compound against 7 Vibrio spp. was performed. Influence of salinity on the production of pyocyanin and the toxicity was done through the compound using brine shrimp lethality assay. Molecular characterization was performed to confirm that the isolates werePseudomonas aeruginosa. Results: Salinity was found to regulate the levels of pyocyanin production, with 5-10 g/L as the optimum. All Pseudomonas isolates grew at salinities ranging from 5 to 70 g/L. Isolates of marine origin produced detectable levels of pyocyanin up to 45 g/L salinity. Brackish and freshwater isolates ceased to produce pyocyanin at salinities above 30 g/L and 20 g/L, respectively. Culture supernatants of all 5 Pseudomonas isolates possessed the ability to restrict the growth of Vibrio spp. and maximum antagonistic effect on Vibrio harveyi was obtained when they were grown at salinities of 5 to 10 g/L. The marine isolate MCCB117, even when grown at a salinity of 45 g/L possessed the ability to inhibit Vibrio spp.Conclusions:Purification and structural elucidation of antagonistic compound were carried out. ideal for application in freshwater, MCCB102 and MCCB103 in brackish water and MCCB117 and The present investigation showed that Pseudomonas aeruginosa MCCB119 would be MCCB118 in marine aquaculture systems as putative probiotics in the management of vibrios.

  1. Effects of Desiccation Practices of Cultured Atlantic Oysters (Crassostrea virginica) on Vibrio spp. in Portersville Bay, Alabama, USA.

    Science.gov (United States)

    Grodeska, Stephanie M; Jones, Jessica L; Arias, Covadonga R; Walton, William C

    2017-08-01

    The expansion of off-bottom aquaculture to the Gulf of Mexico has raised public health concerns for human health officials. High temperatures in the Gulf of Mexico are associated with high levels of Vibrio parahaemolyticus and Vibrio vulnificus. Routine desiccation practices associated with off-bottom aquaculture expose oysters to ambient air, allowing Vibrio spp. to proliferate in the closed oyster. Currently, there is limited research on the length of time needed for Vibrio spp. levels in desiccated oysters to return to background levels, defined as the levels found in oysters that remain continually submersed and not exposed to ambient air. This study determined the time needed to return V. parahaemolyticus, V. vulnificus, and Vibrio cholerae levels to background levels in oysters exposed to the following desiccation practices: 3-h freshwater dip followed by 24-h ambient air exposure, 27-h ambient air exposure, and control. All oysters were submerged at least 2 weeks prior to the beginning of each trial, with the control samples remaining submerged for the duration of each trial. Vibrio spp. levels were enumerated from samples collected on days 0, 1, 2, 3, 7, 10, and 14 after resubmersion using a three-tube most-probable-number enrichment followed by BAX PCR. V. cholerae levels were frequently (92%) below the limit of detection at all times, so they were not statistically analyzed. V. parahaemolyticus and V. vulnificus levels in the 27-h ambient air exposure and the 3-h freshwater dip followed by 24-h ambient air exposure samples were significantly elevated compared with background samples. In most cases, the Vibrio spp. levels in oysters in both desiccation treatments remained elevated compared with background levels until 2 or 3 days post-resubmersion. However, there was one trial in which the Vibrio spp. levels did not return to background levels until day 7. The results of this study provide scientific support that oyster farmers should be required to

  2. Inhibitory effects of Bacillus probionts on growth and toxin production of Vibrio harveyi pathogens of shrimp.

    Science.gov (United States)

    Nakayama, T; Lu, H; Nomura, N

    2009-12-01

    To investigate the effects of Bacillus subtilis, Bacillus licheniformis and Bacillus megaterium in terms of toxin and growth of pathogenic Vibrio harveyi. Three Bacillus probionts were isolated from probiotic BZT aquaculture and identified using a 16S rDNA sequence. Growth inhibition assay showed that supernatants from the 24-h culture of three Bacillus species were able to inhibit the growth of V. harveyi (LMG 4044); B. subtilis was the most effective based on the well diffusion method. Results of a liquid culture model showed that B. subtilis was also widely effective in inhibiting three strains of V. harveyi (isolated from Thailand, the Philippines and LMG 4044), and that both B. licheniformis and B. megaterium inhibit the growth of V. harveyi isolated from the Philippines. Moreover, a haemolytic activity assay demonstrated that V. harveyi (IFO 15634) was significantly decreased by the addition of B. licheniformis or B. megaterium supernatant. Bacillus subtilis inhibited Vibrio growth, and both B. licheniformis and B. megaterium suppressed haemolytic activity in Vibrio. The cell-free supernatants produced by Bacillus probionts inhibit Vibrio disease, and Bacillus probionts might have an influence on Vibrio cell-to-cell communications.

  3. Antibiotic resistance monitoring in Vibrio spp. isolated from rearing environment and intestines of abalone Haliotis diversicolor.

    Science.gov (United States)

    Wang, R X; Wang, J Y; Sun, Y C; B L Yang; A L Wang

    2015-12-30

    546 Vibrio isolates from rearing seawater (292 strains) and intestines of abalone (254 strains) were tested to ten antibiotics using Kirby-Bauer diffusion method. Resistant rates of abalone-derived Vibrio isolates to chloramphenicol (C), enrofloxacin (ENX) and norfloxacin (NOR) were 40%) to kanamycin (KNA), furazolidone (F), tetracycline (TE), gentamicin (GM) and rifampin (RA). 332 isolates from seawater (n=258) and abalone (n=74) were resistant to more than three antibiotics. Peaked resistant rates of seawater-derived isolates to multiple antibiotics were overlapped in May and August. Statistical analysis showed that pH had an important effect on resistant rates of abalone-derived Vibrio isolates to RA, NOR, and ENX. Salinity and dissolved oxygen were negatively correlated with resistant rates of seawater-derived Vibrio isolates to KNA, RA, and PG. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Occurrence and molecular characterisation of Vibrio parahaemolyticus in crustaceans commercialised in Venice area, Italy.

    Science.gov (United States)

    Caburlotto, Greta; Suffredini, Elisabetta; Toson, Marica; Fasolato, Luca; Antonetti, Paolo; Zambon, Michela; Manfrin, Amedeo

    2016-03-02

    Infections due to the pathogenic human vibrios, Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus, are mainly associated with consumption of raw or partially cooked bivalve molluscs. At present, little is known about the presence of Vibrio species in crustaceans and the risk of vibriosis associated with the consumption of these products. The aim of the present study was to evaluate the prevalence and concentration of the main pathogenic Vibrio spp. in samples of crustaceans (n=143) commonly eaten in Italy, taking into account the effects of different variables such as crustacean species, storage conditions and geographic origin. Subsequently, the potential pathogenicity of V. parahaemolyticus strains isolated from crustaceans (n=88) was investigated, considering the classic virulence factors (tdh and trh genes) and four genes coding for relevant proteins of the type III secretion systems 2 (T3SS2α and T3SS2β). In this study, the presence of V. cholerae and V. vulnificus was never detected, whereas 40 samples (28%) were positive for V. parahaemolyticus with an overall prevalence of 41% in refrigerated products and 8% in frozen products. The highest prevalence and average contamination levels were detected in Crangon crangon (prevalence 58% and median value 3400 MPN/g) and in products from the northern Adriatic Sea (35%), with the samples from the northern Venetian Lagoon reaching a median value of 1375 MPN/g. While genetic analysis confirmed absence of the tdh gene, three of the isolates contained the trh gene and, simultaneously, the T3SS2β genes. Moreover three possibly clonal tdh-negative/trh-negative isolates carried the T3SS2α apparatus. The detection of both T3SS2α and T3SS2β apparatuses in V. parahaemolyticus strains isolated from crustaceans emphasised the importance of considering new genetic markers associated with virulence besides the classical factors. Moreover this study represents the first report dealing with Vibrio spp. in

  5. pirABvp-Bearing Vibrio parahaemolyticus and Vibrio campbellii Pathogens Isolated from the Same AHPND-Affected Pond Possess Highly Similar Pathogenic Plasmids

    Directory of Open Access Journals (Sweden)

    Xuan Dong

    2017-10-01

    Full Text Available Acute hepatopancreatic necrosis disease (AHPND is a severe shrimp disease originally shown to be caused by virulent strains of Vibrio parahaemolyticus (VPAHPND. Rare cases of AHPND caused by Vibrio species other than V. parahaemolyticus were reported. We compared an AHPND-causing V. campbellii (VCAHPND and a VPAHPND isolate from the same AHPND-affected pond. Both strains are positive for the virulence genes pirABvp. Immersion challenge test with Litopenaeus vannamei indicated the two strains possessed similar pathogenicity. Complete genome comparison showed that the pirABvp-bearing plasmids in the two strains were highly homologous, and they both shared high homologies with plasmid pVA1, the reported pirABvp-bearing plasmid. Conjugation and DNA-uptake genes were found on the pVA1-type plasmids and the host chromosomes, respectively, which may facilitate the dissemination of pirABvp. Novel variations likely driven by ISVal1 in the genetic contexts of the pirABvp genes were found in the two strains. Moreover, the VCAHPND isolate additionally contains multiple antibiotic resistance genes, which may bring difficulties to control its future outbreak. The dissemination of the pirABvp in non-parahaemolyticus Vibrio also rises the concern of missing detection in industrial settings since the isolation method currently used mainly targeting V. parahaemolyticus. This study provides timely information for better understanding of the causes of AHPND and molecular epidemiology of pirABvp and also appeals for precautions to encounter the dissemination of the hazardous genes.

  6. Assessment of arsenic toxicity in spiked soils and water solutions by the use of bioassays Evaluación de la toxicidad del arsénico en suelos y soluciones contaminadas mediante el uso de bioensayos Avaliação da toxicidade de arsénio em solos contaminados e em soluções aquosas com recurso a bioensaioS

    Directory of Open Access Journals (Sweden)

    Francisco José Martín Peinado

    2012-11-01

    Full Text Available Arsenic (As has become a serious environmental problem due to its extensive use and its potential high toxicity. Furthermore, it tends to accumulate in soils because of its low mobility in this medium. In this study, an assessment of potential As toxicity based on bioassays with Vibrio fischeri and Lactuca sativa was made in soil and water solutions of laboratory-contaminated samples. Soils spiked with 100 ppm of arsenic registered a reduction in As solubility in the soil solution over time, while for the longest incubation periods (8 weeks, the toxicity responses in all of the samples proved negligible for these bioassays. In spiked water solutions with increasing concentrations (0, 0.1, 1, 10, 12.5, 25, 50, and100 ppm As, significant reductions in root elongation and luminescence were found in lettuce and bacteria bioassays, respectively. The effective concentrations (EC50 of As were 1.52 ppm for L. sativa and 4.98 ppm for V. fischeri; this indicated that the L. sativa bioassay was more sensitive to arsenic concentrations in spiked solutions.El arsénico es un elemento que causa serios problemas medioambientales debido a su uso extensivo y a su alta toxicidad, tendiendo a acumularse en suelos debido a su baja movilidad en este medio. En este estudio realizamos la evaluación de la toxicidad potencial de arsénico a partir de bioensayos con Vibrio fischeri y Lactuca sativa en suelos y soluciones acuosas contaminados en laboratorio. Los suelos contaminados con 100 mg kg-1 de arsénico registraron una fuerte reducción de la solubilidad de este contaminante con el tiempo, obteniéndose una respuesta a la toxicidad prácticamente nula a las ocho semanas de incubación. En las soluciones acuosas contaminadas con concentraciones crecientes de arsénico (0, 0,1, 1, 10, 12,5, 25, 50 y 100 ppm As se produjo una reducción significativa en la elongación de raíces y en la luminiscencia en los bioensayos con lechuga y bacterias, respectivamente. La

  7. Investigation of Vibrio alginolyticus, V. harveyi, and V. parahaemolyticus in large yellow croaker, Pseudosciaena crocea (Richardson) reared in Xiangshan Bay, China

    OpenAIRE

    Lu Liu; Mingfeng Ge; Xiaoye Zheng; Zhen Tao; Suming Zhou; Guoliang Wang

    2016-01-01

    Large yellow croaker (LYC), Pseudosciaena crocea is an economically important fish species of mariculture in China. The variation of yearly production of LYC has been increasingly related to the outbreaks of fish diseases. Moreover, Vibrio infections have been identified in this fish frequently. To understand the pattern of Vibrio infections in LYC, we conducted a culture-independent survey of Vibrios in farmed LYC populations using a multiplex PCR method targeting Vibrio alginolyticus, Vibri...

  8. Comparison of classifications of aptamers against Vibrio ...

    African Journals Online (AJOL)

    As a novel method to detect the pathogen Vibrio alginolyticus, 45 aptamers were previously selected and tested. In order to better understand the properties of these aptamers, it was essential to classify these aptamers based on appropriate criteria. The primary structure of 45 aptamers against V. alginolyticus was analyzed ...

  9. Pseudomonas piscicida kills vibrios by two distinct mechanisms

    Science.gov (United States)

    Pseudoalteromonas piscicida is a naturally-occurring marine bacterium which kills competing bacteria, including vibrios. In studies by Richards et al. (AEM00175-17), three strains of P. piscicida were isolated and characterized. Strains secreted proteolytic enzymes which likely killed competing or...

  10. Sucralose induces biochemical responses in Daphnia magna.

    Directory of Open Access Journals (Sweden)

    Ann-Kristin Eriksson Wiklund

    Full Text Available The intense artificial sweetener sucralose has no bioconcentration properties, and no adverse acute toxic effects have been observed in standard ecotoxicity tests, suggesting negligible environmental risk. However, significant feeding and behavioural alterations have been reported in non-standard tests using aquatic crustaceans, indicating possible sublethal effects. We hypothesized that these effects are related to alterations in acetylcholinesterase (AChE and oxidative status in the exposed animals and investigated changes in AChE and oxidative biomarkers (oxygen radical absorbing capacity, ORAC, and lipid peroxidation, TBARS in the crustacean Daphnia magna exposed to sucralose (0.0001-5 mg L(-1. The sucralose concentration was a significant positive predictor for ORAC, TBARS and AChE in the daphnids. Moreover, the AChE response was linked to both oxidative biomarkers, with positive and negative relationships for TBARS and ORAC, respectively. These joint responses support our hypothesis and suggest that exposure to sucralose may induce neurological and oxidative mechanisms with potentially important consequences for animal behaviour and physiology.

  11. Continuous Exposure Of Vibrio Anguillarum To Tropodithietic Acid: Genetic Changes And Influence On Virulence

    DEFF Research Database (Denmark)

    Rasmussen, Bastian Barker; D'Alvise, Paul; Grotkjær, Torben

    2015-01-01

    Introduction: The fish pathogen Vibrio anguillarum is a major problem in aquaculture causing Vibriosis. Bacteria of the Roseobacter clade can antagonize pathogenic vibrios in cultures in live feed such as microalgae, rotifers and Artemia, as well as in fish larvae. Therefore, roseobacters could...

  12. [Characterization of haemolysis of the Vibrio parahaemolyticus no.93].

    Science.gov (United States)

    Su, S C; Lee, C Y

    1997-02-01

    Vibrio parahaemolyticus is a causative bacterium of food poisoning, and the haemolysin produced by this organism has been considered as one of the important virulence factors. In order to understand the pathogenic mechanism of this bacterium, the characteristics of haemolysin from Vibrio parahaemolyticus isolated from Taiwan were studied. One of the clinical strains, V. parahaemolyticus No.93, presents a weak hemolytic zone on 7% NaCl-Wagatsuma medium. The DNA hybridization results show that V. parahemolyticus has neither tdh nor trh gene. V. parahaemolyticus No.93 shows obviously hemolytic zone on 3%-NaCl Wagatsuma medium (human blood). The crude extracellular protein of V. parahaemolyticus No. 93 was evaluated for its heat tolerance and enzyme activities by media assay. The results show that this crude extracellular protein is thermolabile. The crude extracellular protein of V. parahaemolyticus No.93 was analyzed on 10% SDS-PAGE and an apparent band of 64 kDa protein was observed. Furthermore, the crude extracellular protein was analyzed by running gelatin-SDS-PAGE and hemoglobin-SDS-PAGE, and three clear zones on 62 kDa, 52 kDa and 41 kDa were observed on both SDS-PAGEs. Thus we propose that the crude extracellular protein of the V. parahaemolyticus No.93 can degrade gelatin as well as hemoglobin. Whether these protease being the virulence factors of Vibrio parahaemolyticus No.93 needs to be further studied.

  13. Vibrio parahemolyticus septicaemia in a liver transplant patient: a case report

    Science.gov (United States)

    2011-01-01

    Introduction Vibrio parahemolyticus is the leading cause of vibrio-associated gastroenteritis in the United States of America, usually related to poor food handling; only rarely has it been reported to cause serious infections including sepsis and soft tissue infections. In contrast, Vibrio vulnificus is a well-known cause of septicaemia, especially in patients with cirrhosis. We present a patient with V. parahemolyticus sepsis who had an orthotic liver transplant in 2007 and was on immunosuppression for chronic rejection. Clinical suspicion driven by patient presentation, travel to Gulf of Mexico and soft tissue infection resulted in early diagnosis and institution of appropriate antibiotic therapy. Case presentation A 48 year old Latin American man with a history of chronic kidney disease, orthotic liver transplant in 2007 secondary to alcoholic end stage liver disease on immunosuppressants, and chronic rejection presented to the emergency department with fever, vomiting, abdominal pain, left lower extremity swelling and fluid filled blisters after a fishing trip in the Gulf of Mexico. Samples from the blister and blood grew V. parahemolyticus. The patient was successfully treated with ceftriaxone and ciprofloxacin. Conclusion Febrile patients with underlying liver disease and/or immunosuppression should be interviewed regarding recent travel to a coastal area and seafood ingestion. If this history is obtained, appropriate empiric antibiotics must be chosen. Patients with liver disease and/or immunosuppresion should be counselled to avoid eating raw or undercooked molluscan shellfish. People can prevent Vibrio sepsis and wound infections by proper cooking of seafood and avoiding exposure of open wounds to seawater or raw shellfish products. PMID:21548914

  14. Vibrio parahemolyticus septicaemia in a liver transplant patient: a case report.

    Science.gov (United States)

    Fernando, Rajeev R; Krishnan, Sujatha; Fairweather, Morgan G; Ericsson, Charles D

    2011-05-06

    Vibrio parahemolyticus is the leading cause of vibrio-associated gastroenteritis in the United States of America, usually related to poor food handling; only rarely has it been reported to cause serious infections including sepsis and soft tissue infections. In contrast, Vibrio vulnificus is a well-known cause of septicaemia, especially in patients with cirrhosis. We present a patient with V. parahemolyticus sepsis who had an orthotic liver transplant in 2007 and was on immunosuppression for chronic rejection. Clinical suspicion driven by patient presentation, travel to Gulf of Mexico and soft tissue infection resulted in early diagnosis and institution of appropriate antibiotic therapy. A 48 year old Latin American man with a history of chronic kidney disease, orthotic liver transplant in 2007 secondary to alcoholic end stage liver disease on immunosuppressants, and chronic rejection presented to the emergency department with fever, vomiting, abdominal pain, left lower extremity swelling and fluid filled blisters after a fishing trip in the Gulf of Mexico. Samples from the blister and blood grew V. parahemolyticus. The patient was successfully treated with ceftriaxone and ciprofloxacin. Febrile patients with underlying liver disease and/or immunosuppression should be interviewed regarding recent travel to a coastal area and seafood ingestion. If this history is obtained, appropriate empiric antibiotics must be chosen. Patients with liver disease and/or immunosuppresion should be counselled to avoid eating raw or undercooked molluscan shellfish. People can prevent Vibrio sepsis and wound infections by proper cooking of seafood and avoiding exposure of open wounds to seawater or raw shellfish products.

  15. Vibrio parahemolyticus septicaemia in a liver transplant patient: a case report

    Directory of Open Access Journals (Sweden)

    Fairweather Morgan G

    2011-05-01

    Full Text Available Abstract Introduction Vibrio parahemolyticus is the leading cause of vibrio-associated gastroenteritis in the United States of America, usually related to poor food handling; only rarely has it been reported to cause serious infections including sepsis and soft tissue infections. In contrast, Vibrio vulnificus is a well-known cause of septicaemia, especially in patients with cirrhosis. We present a patient with V. parahemolyticus sepsis who had an orthotic liver transplant in 2007 and was on immunosuppression for chronic rejection. Clinical suspicion driven by patient presentation, travel to Gulf of Mexico and soft tissue infection resulted in early diagnosis and institution of appropriate antibiotic therapy. Case presentation A 48 year old Latin American man with a history of chronic kidney disease, orthotic liver transplant in 2007 secondary to alcoholic end stage liver disease on immunosuppressants, and chronic rejection presented to the emergency department with fever, vomiting, abdominal pain, left lower extremity swelling and fluid filled blisters after a fishing trip in the Gulf of Mexico. Samples from the blister and blood grew V. parahemolyticus. The patient was successfully treated with ceftriaxone and ciprofloxacin. Conclusion Febrile patients with underlying liver disease and/or immunosuppression should be interviewed regarding recent travel to a coastal area and seafood ingestion. If this history is obtained, appropriate empiric antibiotics must be chosen. Patients with liver disease and/or immunosuppresion should be counselled to avoid eating raw or undercooked molluscan shellfish. People can prevent Vibrio sepsis and wound infections by proper cooking of seafood and avoiding exposure of open wounds to seawater or raw shellfish products.

  16. Gene response profiles for Daphnia pulex exposed to the environmental stressor cadmium reveals novel crustacean metallothioneins

    Directory of Open Access Journals (Sweden)

    Davey Jennifer C

    2007-12-01

    Full Text Available Abstract Background Genomic research tools such as microarrays are proving to be important resources to study the complex regulation of genes that respond to environmental perturbations. A first generation cDNA microarray was developed for the environmental indicator species Daphnia pulex, to identify genes whose regulation is modulated following exposure to the metal stressor cadmium. Our experiments revealed interesting changes in gene transcription that suggest their biological roles and their potentially toxicological features in responding to this important environmental contaminant. Results Our microarray identified genes reported in the literature to be regulated in response to cadmium exposure, suggested functional attributes for genes that share no sequence similarity to proteins in the public databases, and pointed to genes that are likely members of expanded gene families in the Daphnia genome. Genes identified on the microarray also were associated with cadmium induced phenotypes and population-level outcomes that we experimentally determined. A subset of genes regulated in response to cadmium exposure was independently validated using quantitative-realtime (Q-RT-PCR. These microarray studies led to the discovery of three genes coding for the metal detoxication protein metallothionein (MT. The gene structures and predicted translated sequences of D. pulex MTs clearly place them in this gene family. Yet, they share little homology with previously characterized MTs. Conclusion The genomic information obtained from this study represents an important first step in characterizing microarray patterns that may be diagnostic to specific environmental contaminants and give insights into their toxicological mechanisms, while also providing a practical tool for evolutionary, ecological, and toxicological functional gene discovery studies. Advances in Daphnia genomics will enable the further development of this species as a model organism for

  17. Silver nanoparticles and silver nitrate induce high toxicity to Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio

    International Nuclear Information System (INIS)

    Ribeiro, Fabianne; Gallego-Urrea, Julián Alberto; Jurkschat, Kerstin; Crossley, Alison; Hassellöv, Martin; Taylor, Cameron; Soares, Amadeu M.V.M.; Loureiro, Susana

    2014-01-01

    Silver nanoparticles (AgNP) have gained attention over the years due to the antimicrobial function of silver, which has been exploited industrially to produce consumer goods that vary in type and application. Undoubtedly the increase of production and consumption of these silver-containing products will lead to the entry of silver compounds into the environment. In this study we have used Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio as model organisms to investigate the toxicity of AgNP and AgNO 3 by assessing different biological endpoints and exposure periods. Organisms were exposed following specific and standardized protocols for each species/endpoints, with modifications when necessary. AgNP were characterized in each test-media by Transmission Electron Microscopy (TEM) and experiments were performed by Dynamic Light Scattering (DLS) to investigate the aggregation and agglomeration behavior of AgNP under different media chemical composition and test-period. TEM images of AgNP in the different test-media showed dissimilar patterns of agglomeration, with some agglomerates inside an organic layer, some loosely associated particles and also the presence of some individual particles. The toxicity of both AgNO 3 and AgNP differ significantly based on the test species: we found no differences in toxicity for algae, a small difference for zebrafish and a major difference in toxicity for Daphnia magna. - Highlights: •Effects of silver nanoparticles and nitrate were compared in three aquatic species. •The presence of food on the immobilization assay for Daphnia magna significantly decreased AgNP toxicity. •AgNP and AgNO 3 differ in toxicity according to the test species and endpoint. •AgNP and AgNO 3 induced dissimilar abnormalities on zebrafish embryos' development. •AgNP behavior in the test media will rule its bioavailability and uptake and therefore toxicity

  18. Silver nanoparticles and silver nitrate induce high toxicity to Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Fabianne, E-mail: ribeiro.f@ua.pt [Department of Biology and CESAM, University of Aveiro. Campus Universitario de Santiago, 3810-193. Aveiro (Portugal); Gallego-Urrea, Julián Alberto [Department of Chemistry and Molecular Biologyx, University of Gothenburg, Kemivägen 4, 41296 Gothenburg (Sweden); Jurkschat, Kerstin; Crossley, Alison [Department of Materials, Oxford University Begbroke Science Park OX5 1PF (United Kingdom); Hassellöv, Martin [Department of Chemistry and Molecular Biologyx, University of Gothenburg, Kemivägen 4, 41296 Gothenburg (Sweden); Taylor, Cameron [Department of Materials, Oxford University Begbroke Science Park OX5 1PF (United Kingdom); Soares, Amadeu M.V.M.; Loureiro, Susana [Department of Biology and CESAM, University of Aveiro. Campus Universitario de Santiago, 3810-193. Aveiro (Portugal)

    2014-01-01

    Silver nanoparticles (AgNP) have gained attention over the years due to the antimicrobial function of silver, which has been exploited industrially to produce consumer goods that vary in type and application. Undoubtedly the increase of production and consumption of these silver-containing products will lead to the entry of silver compounds into the environment. In this study we have used Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio as model organisms to investigate the toxicity of AgNP and AgNO{sub 3} by assessing different biological endpoints and exposure periods. Organisms were exposed following specific and standardized protocols for each species/endpoints, with modifications when necessary. AgNP were characterized in each test-media by Transmission Electron Microscopy (TEM) and experiments were performed by Dynamic Light Scattering (DLS) to investigate the aggregation and agglomeration behavior of AgNP under different media chemical composition and test-period. TEM images of AgNP in the different test-media showed dissimilar patterns of agglomeration, with some agglomerates inside an organic layer, some loosely associated particles and also the presence of some individual particles. The toxicity of both AgNO{sub 3} and AgNP differ significantly based on the test species: we found no differences in toxicity for algae, a small difference for zebrafish and a major difference in toxicity for Daphnia magna. - Highlights: •Effects of silver nanoparticles and nitrate were compared in three aquatic species. •The presence of food on the immobilization assay for Daphnia magna significantly decreased AgNP toxicity. •AgNP and AgNO{sub 3} differ in toxicity according to the test species and endpoint. •AgNP and AgNO{sub 3} induced dissimilar abnormalities on zebrafish embryos' development. •AgNP behavior in the test media will rule its bioavailability and uptake and therefore toxicity.

  19. Natural modulators of Vibrios in seawater and shellfish

    Science.gov (United States)

    Naturally occurring marine bacteria, Vibrio parahaemolyticus and V. vulnificus, are major threats to the safety of molluscan shellfish in the US and elsewhere. Illnesses range from mild gastrointestinal upset to septicemia and death. In studies on the uptake and persistence of V. parahaemolyticus ...

  20. antimicrobial susceptibility pattern of vibrio cholerae 01 strains

    African Journals Online (AJOL)

    hi-tech

    East African Medical Journal Vol. 77 No. 7 July 2000. ANTIMICROBIAL SUSCEPTIBILITY PATTERN OF VIBRIO CHOLERAE 01 STRAINS DURING TWO CHOLERA OUTBREAKS IN DAR ES SALAAM,. TANZANIA. W.K. Urassa, MD, MSc, MMed, Lecturer, Department of Microbiology and Immunology, Muhimbili University ...

  1. Antagonistic effect of Pseudomonas aeruginosa isolates from various ecological niches on Vibrio species pathogenic to crustaceans

    Directory of Open Access Journals (Sweden)

    Prabhakaran Priyaja

    2014-01-01

    Full Text Available Objective: To abrogate pathogenic vibrios in aquaculture by testing the potential of Pseudomonas isolates from fresh water, brackish and marine environments as probiotics. Methods: Purification and structural elucidation of antagonistic compound were carried out. Antagonistic activity of the compound against 7 Vibrio spp. was performed. Influence of salinity on the production of pyocyanin and the toxicity was done through the compound using brine shrimp lethality assay. Molecular characterization was performed to confirm that the isolates were Pseudomonas aeruginosa. Results: Salinity was found to regulate the levels of pyocyanin production, with 5-10 g/L as the optimum. All Pseudomonas isolates grew at salinities ranging from 5 to 70 g/L. Isolates of marine origin produced detectable levels of pyocyanin up to 45 g/L salinity. Brackish and freshwater isolates ceased to produce pyocyanin at salinities above 30 g/L and 20 g/L, respectively. Culture supernatants of all 5 Pseudomonas isolates possessed the ability to restrict the growth of Vibrio spp. and maximum antagonistic effect on Vibrio harveyi was obtained when they were grown at salinities of 5 to 10 g/L. The marine isolate MCCB117, even when grown at a salinity of 45 g/L possessed the ability to inhibit Vibrio spp. Conclusions: The present investigation showed that Pseudomonas aeruginosa MCCB119 would be ideal for application in freshwater, MCCB102 and MCCB103 in brackish water and MCCB117 and MCCB118 in marine aquaculture systems as putative probiotics in the management of vibrios.

  2. Comparison of the spectral emission of lux recombinant and bioluminescent marine bacteria.

    Science.gov (United States)

    Thouand, Gérald; Daniel, Philippe; Horry, Habib; Picart, Pascal; Durand, Marie José; Killham, Ken; Knox, Oliver G G; DuBow, Michael S; Rousseau, Michel

    2003-01-01

    The purpose of the present paper was to study the influence of bacteria harbouring the luciferase-encoding Vibrio harveyi luxAB genes upon the spectral emission during growth in batch-culture conditions. In vivo bioluminescence spectra were compared from several bioluminescent strains, either naturally luminescent (Vibrio fischeri and Vibrio harveyi) or in recombinant strains (two Gram-negative Escherichia coli::luxAB strains and a Gram-positive Bacillus subtilis::luxAB strain). Spectral emission was recorded from 400 nm to 750 nm using a highly sensitive spectrometer initially devoted to Raman scattering. Two peaks were clearly identified, one at 491-500 nm (+/- 5 nm) and a second peak at 585-595 (+/- 5 nm) with the Raman CCD. The former peak was the only one detected with traditional spectrometers with a photomultiplier detector commonly used for spectral emission measurement, due to their lack of sensitivity and low resolution in the 550-650 nm window. When spectra were compared between all the studied bacteria, no difference was observed between natural or recombinant cells, between Gram-positive and Gram-negative strains, and growth conditions and growth medium were not found to modify the spectrum of light emission. Copyright 2003 John Wiley & Sons, Ltd.

  3. Phytoplankton production systems in a shellfish hatchery: variations of the bacterial load and diversity of vibrios.

    Science.gov (United States)

    Dubert, J; Fernández-Pardo, A; Nóvoa, S; Barja, J L; Prado, S

    2015-06-01

    Outbreaks of disease caused by some Vibrio species represent the main production bottleneck in shellfish hatcheries. Although the phytoplankton used as food is one of the main sources of bacteria, studies of the associated bacterial populations, specifically vibrios, are scarce. The aim of the study was the microbiological monitoring of the microalgae as the first step in assessing the risk disease for bivalve cultures. Two phytoplankton production systems were sampled weekly throughout 1-year period in a bivalve hatchery. Quantitative analysis revealed high levels of marine heterotrophic bacteria in both systems throughout the study. Presumptive vibrios were detected occasionally and at low concentrations. In most of the cases, they belonged to the Splendidus and Harveyi clades. The early detection of vibrios in the microalgae may be the key for a successful bivalve culture. Their abundance and diversity were affected by factors related to the hatchery environment. This work represents the first long study where the presence of vibrios was evaluated rigorously in phytoplankton production systems and provides a suitable microbiological protocol to control and guarantee the quality of the algal cultures to avoid the risk of transferring potential pathogens to shellfish larvae and/or broodstock. © 2015 The Society for Applied Microbiology.

  4. Occurrence of Vibrio and Salmonella species in mussels (Mytilus galloprovincialis) collected along the Moroccan Atlantic coast.

    Science.gov (United States)

    Mannas, Hasna; Mimouni, Rachida; Chaouqy, Noureddine; Hamadi, Fatima; Martinez-Urtaza, Jaime

    2014-01-01

    This study reports the occurrence of different Vibrio and Salmonella species in 52 samples of Mytilus galloprovincialis collected from four sites along the Atlantic coast between Agadir and Essaouira (Anza, Cap Ghir, Imssouane and Essaouira). The level of Escherichia coli (E. coli) was also determined to evaluate the degree of microbial pollution in the investigated areas. In this study three methods were used : AFNOR NF EN ISO 6579 V08-013 for Salmonella spp., the provisional method routinely used by several laboratories (Institut Pasteur, Paris,…) for Vibrio cholerae and Vibrio parahaemolyticus in the seafood, and the most probable number method (MPN) using Norm ISO/TS 16649-3 (2005) for E. coli. The most frequently isolated Vibrios were Vibrio alginolyticus (90.4% of samples), followed by V. cholerae non O1 non O139 (15.4%) and V. parahaemolyticus (7.7%). Salmonella spp. was found in 15% of the samples. The number of E. coli ranged between 0.2/100 g and 1.8 10(3) /100 g of mussel soft tissues. This study indicates the potential sanitary risk associated with the presence of pathogenic bacteria in cultivated mussels in the two populous regions of southern Morocco, where shellfish production and maritime tourism are important to the local economy.

  5. Investigation of household contamination of Vibrio cholerae in Bangladesh

    DEFF Research Database (Denmark)

    Hossain, Zenat Zebin; Farhana, Israt; Mohan Tulsiani, Suhella

    . cholerae El Tor strain N16961, showed hemolysis and proteolysis activity but none of them exhibited any hemagglutinin activity on human erythrocytes. The study findings indicate that V. cholerae contamination is mostly originated in and around kitchen area rather than latrine area. Contaminated food...... and water supply may be the reason behind this relatively high presence of virulence factors in food plates and water pots. Direct exposure routes of disease transmission should be a major consideration in cholera prevention policies. Investigation of household contamination of Vibrio cholerae in Bangladesh......The role of in-house transmission on the incidence of Vibrio cholerae, the deadly waterborne pathogen, is still not developed. The aim of the current study was to investigate possible contamination routes in household domain for effective cholera control in Bangladesh. To examine the prevalence...

  6. Repair of ultraviolet-light-induced DNA damage in Vibrio cholerae

    International Nuclear Information System (INIS)

    Das, G.; Sil, K.; Das, J.

    1981-01-01

    Repair of ultraviolet-light-induced DNA damage in a highly pathogenic Gram-negative bacterium, Vibrio cholerae, has been examined. All three strains of V. cholerae belonging to two serotypes, Inaba and Ogawa, are very sensitive to ultraviolet irradiation, having inactivation cross-sections ranging from 0.18 to 0.24 m 2 /J. Although these cells are proficient in repairing the DNA damage by a photoreactivation mechanism, they do not possess efficient dark repair systems. The mild toxinogenic strain 154 of classical Vibrios presumably lacks any excision repair mechanism and studies of irradiated cell DNA indicate that the ultraviolet-induced pyrimidine dimers may not be excised. Ultraviolet-irradiated cells after saturation of dark repair can be further photoreactivated. (Auth.)

  7. Vibrio bacteria in raw oysters: managing risks to human health.

    Science.gov (United States)

    Froelich, Brett A; Noble, Rachel T

    2016-03-05

    The human-pathogenic marine bacteria Vibrio vulnificus and V. parahaemolyticus are strongly correlated with water temperature, with concentrations increasing as waters warm seasonally. Both of these bacteria can be concentrated in filter-feeding shellfish, especially oysters. Because oysters are often consumed raw, this exposes people to large doses of potentially harmful bacteria. Various models are used to predict the abundance of these bacteria in oysters, which guide shellfish harvest policy meant to reduce human health risk. Vibrio abundance and behaviour varies from site to site, suggesting that location-specific studies are needed to establish targeted risk reduction strategies. Moreover, virulence potential, rather than simple abundance, should be also be included in future modeling efforts. © 2016 The Author(s).

  8. Genetic variation in the cellular response of Daphnia magna (Crustacea: Cladocera) to its bacterial parasite.

    Science.gov (United States)

    Auld, Stuart K J R; Scholefield, Jennifer A; Little, Tom J

    2010-11-07

    Linking measures of immune function with infection, and ultimately, host and parasite fitness is a major goal in the field of ecological immunology. In this study, we tested for the presence and timing of a cellular immune response in the crustacean Daphnia magna following exposure to its sterilizing endoparasite Pasteuria ramosa. We found that D. magna possesses two cell types circulating in the haemolymph: a spherical one, which we call a granulocyte and an irregular-shaped amoeboid cell first described by Metchnikoff over 125 years ago. Daphnia magna mounts a strong cellular response (of the amoeboid cells) just a few hours after parasite exposure. We further tested for, and found, considerable genetic variation for the magnitude of this cellular response. These data fostered a heuristic model of resistance in this naturally coevolving host-parasite interaction. Specifically, the strongest cellular responses were found in the most susceptible hosts, indicating resistance is not always borne from a response that destroys invading parasites, but rather stems from mechanisms that prevent their initial entry. Thus, D. magna may have a two-stage defence--a genetically determined barrier to parasite establishment and a cellular response once establishment has begun.

  9. Thermal death rate of ascospores of Neosartorya fischeri ATCC 200957 in the presence of organic acids and preservatives in fruit juices.

    Science.gov (United States)

    Rajashekhara, E; Suresh, E R; Ethiraj, S

    1998-10-01

    Heat-resistant molds, including Neosartorya fischeri, are known to spoil thermally processed fruit products. The control measures required for such problems must not cause an appreciable loss of the organoleptic qualities of the final products. In the present study we determined the thermal death rates of ascospores of N. fischeri ATCC 200957 in fruit juices containing organic acids and preservatives. The ascospores were able to survive for more than 6 h of heating at 75 degrees C, 5 h at 80 degrees C, and 3 to 4 h at 85 degrees C in mango or grape juice. Of the four organic acids tested, citric acid exhibited the maximal destruction of ascospores in mango juice at 85 degrees C (1/k = 27.22 min), and tartaric acid the least (1/k = 61.73 min). The effect of common preservatives on the thermal death rates of ascospores at .85 degrees C in mango and grape juices was studied. Almost similar effects on thermal inactivation of ascospores were noted when potassium sorbate (1/k = 29.38 min) or sodium benzoate (1/k = 27.64 min) or the combination of both (1/k = 27.53 min) was used in mango juice. In grape juice, potassium sorbate (1/k = 25.07 min) was more effective than sodium benzoate (1/k = 50.08 min) or the combination of both (1/k = 40.79 min) in inactivation of ascospores of the mold. The thermal death rate (1/k) values in mango and grape juices in the absence of any preservative were 63.51 and 69.27 min respectively.

  10. Exoproteome and Secretome Derived Broad Spectrum Novel Drug and Vaccine Candidates in Vibrio cholerae Targeted by Piper betel Derived Compounds

    Science.gov (United States)

    Barh, Debmalya; Barve, Neha; Gupta, Krishnakant; Chandra, Sudha; Jain, Neha; Tiwari, Sandeep; Leon-Sicairos, Nidia; Canizalez-Roman, Adrian; Rodrigues dos Santos, Anderson; Hassan, Syed Shah; Almeida, Síntia; Thiago Jucá Ramos, Rommel; Augusto Carvalho de Abreu, Vinicius; Ribeiro Carneiro, Adriana; de Castro Soares, Siomar; Luiz de Paula Castro, Thiago; Miyoshi, Anderson; Silva, Artur; Kumar, Anil; Narayan Misra, Amarendra; Blum, Kenneth; Braverman, Eric R.; Azevedo, Vasco

    2013-01-01

    Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC) for most of the pathogenic Vibrio strains. Two targets (uppP and yajC) are novel to Vibrio, and two targets (uppP and ompU) can be used to develop both drugs and vaccines (dual targets) against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species. PMID:23382822

  11. Exoproteome and secretome derived broad spectrum novel drug and vaccine candidates in Vibrio cholerae targeted by Piper betel derived compounds.

    Directory of Open Access Journals (Sweden)

    Debmalya Barh

    Full Text Available Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC for most of the pathogenic Vibrio strains. Two targets (uppP and yajC are novel to Vibrio, and two targets (uppP and ompU can be used to develop both drugs and vaccines (dual targets against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species.

  12. Combined anaerobic–ozonation process for treatment of textile wastewater: Removal of acute toxicity and mutagenicity

    Energy Technology Data Exchange (ETDEWEB)

    Punzi, Marisa, E-mail: marisa.punzi@biotek.lu.se [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Nilsson, Filip [Water and Environmental Engineering at the Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Anbalagan, Anbarasan [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Svensson, Britt-Marie [School of Education and Environment, Kristianstad University, SE-291 88 Kristianstad (Sweden); Jönsson, Karin [Water and Environmental Engineering at the Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Mattiasson, Bo; Jonstrup, Maria [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden)

    2015-07-15

    Highlights: • COD and UV absorbance were effectively reduced. • The treated effluents were non-toxic to Artemia salina and Vibrio fischeri. • The real textile wastewater was mutagenic. • Mutagenicity persisted after bio treatment and even more after a short ozonation. • Higher ozone doses completely remove mutagenicity. - Abstract: A novel set up composed of an anaerobic biofilm reactor followed by ozonation was used for treatment of artificial and real textile effluents containing azo dyes. The biological treatment efficiently removed chemical oxygen demand and color. Ozonation further reduced the organic content of the effluents and was very important for the degradation of aromatic compounds, as shown by the reduction of UV absorbance. The acute toxicity toward Vibrio fischeri and the shrimp Artemia salina increased after the biological treatment. No toxicity was detected after ozonation with the exception of the synthetic effluent containing the highest concentration, 1 g/l, of the azo dye Remazol Red. Both untreated and biologically treated textile effluents were found to have mutagenic effects. The mutagenicity increased even further after 1 min of ozonation. No mutagenicity was however detected in the effluents subjected to longer exposure to ozone. The results of this study suggest that the use of ozonation as short post-treatment after a biological process can be beneficial for the degradation of recalcitrant compounds and the removal of toxicity of textile wastewater. However, monitoring of toxicity and especially mutagenicity is crucial and should always be used to assess the success of a treatment strategy.

  13. Evaluación de la recuperación de suelos contaminados por el vertido de Aznalcóllar

    Directory of Open Access Journals (Sweden)

    Margarita María Sarria Carabalí

    2015-04-01

    Full Text Available Los suelos afectados por el accidente de la mina de Aznalcóllar, Sevilla (España en 1998 fueron remediados para disminuir la contaminación generada principalmente por As, Cu, Pb y Zn. Para evaluar la recuperación de los suelos, especialmente los que se sometieron a medidas de remediación, se hizo un muestreo en tres perfiles: suelo contaminado (SC, suelo remediado (SR y suelo no contaminado (SNC en el sector 'Puente de las Doblas', 10 años después de ocurrido el accidente. Se determinaron las propiedades físico-químicas y se realizaron bioensayos con la bacteria Vibrio fischeri y Lactuca sativa (lechuga, para valorar la toxicidad generada por dichos metales. El SR presentó propiedades similares a las del SNC, pero con una mayor concentración de metales totales que no superan el nivel crítico para parques naturales y zonas forestales. Las concentraciones de Cu y Zn en fase soluble eran superiores a los valores máximos deseables en la solución del suelo; además, ambos metales generaron toxicidad en Vibrio fischeri, entre 40 y 50 cm de profundidad, asociada con pH ácido. Se sugiere continuar los seguimientos periódicos con el fin de evaluar la evolución y la dispersión potencial de la toxicidad detectada en los suelos recuperados, y efectuar las actuaciones necesarias para la recuperación ambiental.

  14. VanT, a homologue of Vibrio harveyi LuxR, regulates serine, metalloprotease, pigment, and biofilm production in Vibrio anguillarum.

    Science.gov (United States)

    Croxatto, Antony; Chalker, Victoria J; Lauritz, Johan; Jass, Jana; Hardman, Andrea; Williams, Paul; Cámara, Miguel; Milton, Debra L

    2002-03-01

    Vibrio anguillarum possesses at least two N-acylhomoserine lactone (AHL) quorum-sensing circuits, one of which is related to the luxMN system of Vibrio harveyi. In this study, we have cloned an additional gene of this circuit, vanT, encoding a V. harveyi LuxR-like transcriptional regulator. A V. anguillarum Delta vanT null mutation resulted in a significant decrease in total protease activity due to loss of expression of the metalloprotease EmpA, but no changes in either AHL production or virulence. Additional genes positively regulated by VanT were identified from a plasmid-based gene library fused to a promoterless lacZ. Three lacZ fusions (serA::lacZ, hpdA-hgdA::lacZ, and sat-vps73::lacZ) were identified which exhibited decreased expression in the Delta vanT strain. SerA is similar to 3-phosphoglycerate dehydrogenases and catalyzes the first step in the serine-glycine biosynthesis pathway. HgdA has identity with homogentisate dioxygenases, and HpdA is homologous to 4-hydroxyphenylpyruvate dioxygenases (HPPDs) involved in pigment production. V. anguillarum strains require an active VanT to produce high levels of an L-tyrosine-induced brown color via HPPD, suggesting that VanT controls pigment production. Vps73 and Sat are related to Vibrio cholerae proteins encoded within a DNA locus required for biofilm formation. A V. anguillarum Delta vanT mutant and a mutant carrying a polar mutation in the sat-vps73 DNA locus were shown to produce defective biofilms. Hence, a new member of the V. harveyi LuxR transcriptional activator family has been characterized in V. anguillarum that positively regulates serine, metalloprotease, pigment, and biofilm production.

  15. Diversity and dynamics of the Vibrio community in well water used for drinking in Guinea-Bissau (West Africa).

    Science.gov (United States)

    Machado, A; Bordalo, A A

    2014-09-01

    Bacteria of the genus Vibrio are ubiquitous in aquatic environments and can be found either in culturable or in a viable but nonculturable (VBNC) state. The genus comprises many pathogenic species accountable for water and food-borne diseases that prove to be fatal, especially in developing countries, as in Guinea-Bissau (West Africa), where cholera is endemic. In order to ascertain the abundance and structure of Vibrio spp. community in well waters that serve as the sole source of water for the population, quantitative polymerase chain reaction (qPCR), PCR-denaturant gradient gel electrophoresis (DGGE), and cloning approaches were used. Results suggest that Vibrio spp. were present throughout the year in acidic, freshwater wells with a seasonal community composition shift. Vibrio spp. abundance was in accordance with the abundance found in coastal environments. Sequences closely related to pathogenic Vibrio species were retrieved from well water revealing exposure of the population to such pathogens. pH, ammonium, and turbidity, regulated by the rain pattern, seem to be the variables that contributed mostly to the shaping and selection of the Vibrio spp. community. These results reinforce the evidence for water monitoring with culture-independent methods and the clear need to create/recover water infrastructures and a proper water resources management in West African countries with similar environmental conditions.

  16. Physiological responses of Daphnia pulex to acid stress

    Directory of Open Access Journals (Sweden)

    Pirow Ralph

    2009-04-01

    Full Text Available Abstract Background Acidity exerts a determining influence on the composition and diversity of freshwater faunas. While the physiological implications of freshwater acidification have been intensively studied in teleost fish and crayfish, much less is known about the acid-stress physiology of ecologically important groups such as cladoceran zooplankton. This study analyzed the extracellular acid-base state and CO2 partial pressure (PCO2, circulation and ventilation, as well as the respiration rate of Daphnia pulex acclimated to acidic (pH 5.5 and 6.0 and circumneutral (pH 7.8 conditions. Results D. pulex had a remarkably high extracellular pH of 8.33 and extracellular PCO2 of 0.56 kPa under normal ambient conditions (pH 7.8 and normocapnia. The hemolymph had a high bicarbonate concentration of 20.9 mM and a total buffer value of 51.5 meq L-1 pH-1. Bicarbonate covered 93% of the total buffer value. Acidic conditions induced a slight acidosis (ΔpH = 0.16–0.23, a 30–65% bicarbonate loss, and elevated systemic activities (tachycardia, hyperventilation, hypermetabolism. pH 6.0 animals partly compensated the bicarbonate loss by increasing the non-bicarbonate buffer value from 2.0 to 5.1 meq L-1 pH-1. The extracellular PCO2 of pH 5.5 animals was significantly reduced to 0.33 kPa, and these animals showed the highest tolerance to a short-term exposure to severe acid stress. Conclusion Chronic exposure to acidic conditions had a pervasive impact on Daphnia's physiology including acid-base balance, extracellular PCO2, circulation and ventilation, and energy metabolism. Compensatory changes in extracellular non-bicarbonate buffering capacity and the improved tolerance to severe acid stress indicated the activation of defense mechanisms which may result from gene-expression mediated adjustments in hemolymph buffer proteins and in epithelial properties. Mechanistic analyses of the interdependence between extracellular acid-base balance and CO2 transport

  17. Review on the acute Daphnia magna toxicity test – Evaluation of the sensitivity and the precision of assays performed with organisms from laboratory cultures or hatched from dormant eggs

    Directory of Open Access Journals (Sweden)

    G. Persoone

    2009-08-01

    Full Text Available One of the most internationally used bioassays for toxicity screening of chemicals and for toxicity monitoring of effluents and contaminated waters is the acute toxicity test with daphnid crustaceans, and in particular that performed with Daphnia magna.Standard methods have been developed for this assay that were gradually endorsed by national and international organisations dealing with toxicity testing procedures, in view of its application within a regulatory framework. As for all toxicity tests, the organisms used for the acute D. magna assay have to be obtained from live stocks which are cultured in the laboratory on live food (micro-algae.Unsurprisingly the various standard protocols of this particular assay differ – at least to a certain extent – with regard to the test organism culturing conditions. In addition, some technical aspects of the toxicity test such as the effect criterion (mortality of immobility, the exposure time, the type of dilution water, etc., also vary from one standard to another.Although this particular assay is currently used in many countries, the technical and biological problems inherent in year-round culturing and availability of the biological material and the culturing/maintenance costs of live stocks restrict its application to a limited number of highly specialised laboratories.This fundamental bottleneck in toxicity testing triggered investigations which brought forward the concept of “microbiotests” or “small-scale” toxicity tests. “Culture/maintenance free” aquatic microbiotests with species of different phylogenetic groups were developed in the early 1990s at the Laboratory for Environmental Toxicology and Aquatic Ecology at the Ghent University in Belgium.These assays which were given the generic name “Toxkits”, are unique in that they employ dormant stages (“cryptobiotic eggs” of the test species, which can be stored for long periods of time and “hatched” at the time of

  18. Study of acute ecotoxicity of Resveratrol in Daphnia similis irradiated and non-irradiated; Estudo da toxicidade aguda do Resveratrol em Daphnia similis irradiadas e não irradiadas

    Energy Technology Data Exchange (ETDEWEB)

    Ormenio, Matheus B.; Mazieiro, Joana S.; Rogero, Sizue O.; Rogero, José R. Rogero, E-mail: matheus.ormenio@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    Resveratrol is synthesized by a wide variety of plants in response to ultraviolet (UV) radiation or action of certain pathogens. It is a compound with ability to protect cells from free radicals, responsible for the natural process of cellular aging. It is known that resveratrol has a radiomodifying effect, in addition to the antioxidant potential, anti-inflammatory, against cardiovascular diseases. The increasing use of resveratrol as a function of biological activities has led to concern about toxicity. In the ecotoxicological area, acute ecotoxicity tests are performed on aquatic organisms that lethal effects of certain substances and / or environmental samples. These tests are important in providing critical information for the development and adoption of criteria for improvement environmental quality. In these tests Cladoceras are widely used as test organisms due to their extreme susceptibility to toxicants in the environment and because they are easy to handle in the laboratory. In this study, it was used Daphnia similis to verify the toxic effect of resveratrol on this non-irradiated organism and irradiated with gamma radiation. First, toxicity studies of resveratrol and gamma Daphnia similis, where the lethal dose (LD50) of the 585.43 Gy radiation was determined and the EC50 concentration of resveratrol that causes immobility in 50% of the organisms in the assay, of 6.08 μM. Based on these data, the study will be continued to assess the toxic effect of radiation on organisms that have been exposed prior to resveratrol, i.e, to verify the radiomodifying effect of resveratrol.

  19. The Anatomy and Morphology of the Adult Bacterial Light Organ of Euprymna scolopes Berry (Cephalopoda:Sepiolidae).

    Science.gov (United States)

    McFall-Ngai, M; Montgomery, M K

    1990-12-01

    The sepiolid squid, Euprymna scolopes, has a bilobed luminous organ in the center of the mantle cavity, associated with the ink sac. Luminous bacterial symbionts (Vibrio fischeri) are housed in narrow channels of host epithelial tissue. The channels of each lobe of the light organ empty into a ciliated duct, which is contiguous with the mantle cavity of the squid. Surrounding the symbiotic bacteria and their supportive host cells are host tissues recruited into the light organ system, including a muscle-derived lens and thick reflector that appear to permit the squid to control the quality of bacterial light emission.

  20. Evaluation of the natural prevalence of Vibrio spp. in Uruguayan mussels (Mytilus sp.) and their control using irradiation

    International Nuclear Information System (INIS)

    Lopez, C.

    2001-01-01

    The presence of potentially pathogenic bacteria belonging to the Vibrionacea, especially Vibrio cholerae, and of Salmonella spp., was examined in fresh Uruguayan mussels (Mytilus sp.) during two annual seasons. The radiation decimal reduction dose (D 10 ) of various toxigenic strains of Vibrio cholerae was determined to vary in vitro between 0.11 and 0.19 kGy. These results and those from the examination of natural Vibrio spp. contamination in mussels were used to conclude that 1.0 kGy would be enough to render Uruguayan mussels Vibrio-safe. Mussels irradiated in the shell at the optical dose survived long enough to allow the eventual introduction of irradiation as an effective intervention measure without affecting local marketing practices, and making it possible to market the fresh mussels live, as required by Uruguayan legislation. (author)

  1. Biocompatible capped iron oxide nanoparticles for Vibrio cholerae detection

    International Nuclear Information System (INIS)

    Sharma, Anshu; Rawat, Kamla; Solanki, Pratima R; Bohidar, H B; Baral, Dinesh

    2015-01-01

    We report the studies relating to fabrication of an efficient immunosensor for Vibrio cholerae detection. Magnetite (iron oxide (Fe 3 O 4 )) nanoparticles (NPs) have been synthesized by the co-precipitation method and capped by citric acid (CA). These NPs were electrophoretically deposited onto indium-tin-oxide (ITO)-coated glass substrate and used for immobilization of monoclonal antibodies against Vibrio cholerae (Ab) and bovine serum albumin (BSA) for Vibrio cholerae detection using an electrochemical technique. The structural and morphological studies of Fe 3 O 4 and CA-Fe 3 O 4 /ITO were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) techniques. The average crystalline size of Fe 3 O 4 , CA-Fe 3 O 4 nanoparticles obtained were about 29 ± 1 nm and 37 ± 1 nm, respectively. The hydrodynamic radius of the nanoparticles was found to be 77.35 nm (Fe 3 O 4 ) and 189.51 nm (CA-Fe 3 O 4 ) by DLS measurement. The results of electrochemical response studies of the fabricated BSA/Ab/CA-Fe 2 O 3 /ITO immunosensor exhibits a good detection range of 12.5–500 ng mL −1 with a low detection limit of 0.32 ng mL −1 , sensitivity 0.03 Ω/ng ml −1 cm −2 , and reproducibility more than 11 times. (paper)

  2. Bactericidal Permeability-Increasing Proteins Shape Host-Microbe Interactions

    Directory of Open Access Journals (Sweden)

    Fangmin Chen

    2017-04-01

    Full Text Available We characterized bactericidal permeability-increasing proteins (BPIs of the squid Euprymna scolopes, EsBPI2 and EsBPI4. They have molecular characteristics typical of other animal BPIs, are closely related to one another, and nest phylogenetically among invertebrate BPIs. Purified EsBPIs had antimicrobial activity against the squid’s symbiont, Vibrio fischeri, which colonizes light organ crypt epithelia. Activity of both proteins was abrogated by heat treatment and coincubation with specific antibodies. Pretreatment under acidic conditions similar to those during symbiosis initiation rendered V. fischeri more resistant to the antimicrobial activity of the proteins. Immunocytochemistry localized EsBPIs to the symbiotic organ and other epithelial surfaces interacting with ambient seawater. The proteins differed in intracellular distribution. Further, whereas EsBPI4 was restricted to epithelia, EsBPI2 also occurred in blood and in a transient juvenile organ that mediates hatching. The data provide evidence that these BPIs play different defensive roles early in the life of E. scolopes, modulating interactions with the symbiont.

  3. Evaluation of bacterial surfactant toxicity towards petroleum degrading microorganisms.

    Science.gov (United States)

    Lima, Tânia M S; Procópio, Lorena C; Brandão, Felipe D; Leão, Bruna A; Tótola, Marcos R; Borges, Arnaldo C

    2011-02-01

    The acute toxicity of bacterial surfactants LBBMA111A, LBBMA155, LBBMA168, LBBMA191 and LBBMA201 and the synthetic surfactant sodium dodecyl sulfate (SDS) on the bioluminescent bacterium Vibrio fischeri was evaluated by measuring the reduction of light emission (EC(20)) by this microorganism when exposed to different surfactant concentrations. Moreover, the toxic effects of different concentrations of biological and synthetic surfactants on the growth of pure cultures of isolates Acinetobacter baumannii LBBMA04, Acinetobacter junni LBBMA36, Pseudomonas sp. LBBMA101B and Acinetobacter baumanni LBBMAES11 were evaluated in mineral medium supplemented with glucose. The EC(20) values obtained confirmed that the biosurfactants have a significantly lower toxicity to V. fischeri than the SDS. After 30 min of exposure, bacterial luminescence was almost completely inhibited by SDS at a concentration of 4710 mg L(-1). Growth reduction of pure bacterial cultures caused by the addition of biosurfactants to the growth medium was lower than that caused by SDS. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Ecotoxicological evaluation of industrial port of Venice (Italy) sediment samples after a decontamination treatment

    International Nuclear Information System (INIS)

    Libralato, Giovanni; Losso, Chiara; Arizzi Novelli, Alessandra; Citron, Marta; Della Sala, Stefano; Zanotto, Emanuele; Cepak, Franka; Volpi Ghirardini, Annamaria

    2008-01-01

    This work assesses the ecotoxicological effects of polluted sediment after a decontamination treatment process using a new sediment washing technique. Sediment samples were collected from four sites in Marghera Port industrial channels (Venice, Italy). Ecotoxicological evaluations were performed with Vibrio fischeri and Crassostrea gigas bioassays. Whole sediment and elutriate were deemed as the most suitable environmental matrices for this study. Toxicity scores developed in the Lagoon of Venice for V. fischeri on whole sediment and for C. gigas on elutriate were considered for the final ranking of samples. Ecotoxicological results showed that the treated sediment samples presented both acute and sub-chronic toxicities, which were mainly attributed to the presence of some remaining chemicals such as metals and polyaromatic hydrocarbons. The acute toxicity ranged from low to medium, while the sub-chronic one from absent to very high, suggesting that treated sediments could not be reused in direct contact with seawater. - A sediment washing technique was assessed for port contaminated sediment remediation and reuse, indicating its reduced efficiency and the need for further improvements

  5. Ecotoxicological evaluation of industrial port of Venice (Italy) sediment samples after a decontamination treatment

    Energy Technology Data Exchange (ETDEWEB)

    Libralato, Giovanni [Environmental Sciences Department, Venice University Ca Foscari, Campo della Celestia 2737/b, I-30122 Venice (Italy)], E-mail: giovanni.libralato@unive.it; Losso, Chiara; Arizzi Novelli, Alessandra [Environmental Sciences Department, Venice University Ca Foscari, Campo della Celestia 2737/b, I-30122 Venice (Italy); Citron, Marta; Della Sala, Stefano; Zanotto, Emanuele [Environmental Department, Venice Port Authority, Zattere 1401, I-30123, Venice (Italy); Cepak, Franka [Institute of Public Health, Vojkovo nabrezje 4a, 6000 Koper (Slovenia); Volpi Ghirardini, Annamaria [Environmental Sciences Department, Venice University Ca Foscari, Campo della Celestia 2737/b, I-30122 Venice (Italy)

    2008-12-15

    This work assesses the ecotoxicological effects of polluted sediment after a decontamination treatment process using a new sediment washing technique. Sediment samples were collected from four sites in Marghera Port industrial channels (Venice, Italy). Ecotoxicological evaluations were performed with Vibrio fischeri and Crassostrea gigas bioassays. Whole sediment and elutriate were deemed as the most suitable environmental matrices for this study. Toxicity scores developed in the Lagoon of Venice for V. fischeri on whole sediment and for C. gigas on elutriate were considered for the final ranking of samples. Ecotoxicological results showed that the treated sediment samples presented both acute and sub-chronic toxicities, which were mainly attributed to the presence of some remaining chemicals such as metals and polyaromatic hydrocarbons. The acute toxicity ranged from low to medium, while the sub-chronic one from absent to very high, suggesting that treated sediments could not be reused in direct contact with seawater. - A sediment washing technique was assessed for port contaminated sediment remediation and reuse, indicating its reduced efficiency and the need for further improvements.

  6. Antimicrobial Potential of Helicanthus elastica (Desr. Danser - A less explored Indian mistletoe Growing on Mango Trees

    Directory of Open Access Journals (Sweden)

    Koppala Narayana Sunil Kumar

    2014-10-01

    Full Text Available Helicanthus elastica (Desr. Danser (Loranthaceae is a less-known medicinally important mistletoe species occurring in India. It is used to check abortion, and also in vesical calculi and kidney affections. There are no detailed studies reporting the antimicrobial potential of this plant. Based on the traditional use and the rich phenolic composition of the whole plant, the antimicrobial property of the alcohol extract was analyzed and the results are outlined in the present paper. For the analysis, zone of inhibition, and minimum inhibitory concentration were used, and the total activity was assayed by standard methodologies. The antimicrobial activity was studied against bacteria like Aeromonas hydrophila, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pyogenes, Vibrio fischeri, and a fungus Candida albicans. Of the eight tested bacteria, the alcoholic extract of H. elastica was found to be active against K. pneumoniae, A. hydrophila, E. coli, and V. fischeri at concentration ranging from 250 to 500 μg/ml. C. albicans showed inhibition only at a concentration of 2000 μg/ml.

  7. Chemical and ecotoxicological analyses of sediments and elutriates of contaminated rivers due to e-waste recycling activities using a diverse battery of bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Wang, F.; Leung, A.O.W.; Wu, S.C.; Yang, M.S. [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong); Wong, M.H., E-mail: mhwong@hkbu.edu.h [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong)

    2009-07-15

    A multi-trophic, multi-exposure phase assessment approach was applied to characterize the toxicity of sediments collected from two rivers in Guiyu, China, an e-waste recycling centre. Elutriate toxicity tests (bacterium Vibrio fischeri and microalga Selenastrum capricornutum) and whole sediment toxicity test (crustacean Heterocypris incongruens) showed that most sediments exhibited acute toxicity, due to elevated heavy metals and PAHs levels, and low pH caused by uncontrolled acid discharge. The survival rates of crustaceans were negatively (p < 0.05) correlated with total PAHs in sediments (411-1755 mg kg{sup -1}); EC50s of V. fischeri on the elutriates were significantly correlated with elutriate pH (p < 0.01). Significant (p < 0.05) correlations between the induction of hepatic metallothionein in tilapia (Oreochromis mossambicus) and metal concentrations (Cu, Zn, Pb) in sediments were also observed, when fish were fed with diets containing sediment. The results showed that uncontrolled e-waste recycling activities may bring adverse effects to local aquatic ecosystem. - Toxicity tests using different trophic organisms provided important information, supplementing chemical analyses.

  8. Genome Sequence of Vibrio cholerae Strain O1 Ogawa El Tor, Isolated in Mexico, 2013

    OpenAIRE

    Díaz-Quiñonez, José Alberto; Hernández-Monroy, Irma; López-Martínez, Irma; Ortiz-Alcántara, Joanna; González-Durán, Elizabeth; Ruiz-Matus, Cuitláhuac; Kuri-Morales, Pablo; Ramírez-González, José Ernesto

    2014-01-01

    We present the draft genome sequence of Vibrio cholerae InDRE 3140 recovered in 2013 during a cholera outbreak in Mexico. The genome showed the Vibrio 7th pandemic islands VSP1 and VSP2, the pathogenic islands VPI-1 and VPI-2, the integrative and conjugative element SXT/R391 (ICE-SXT), and both prophages CTXφ and RS1φ.

  9. Chemical and structural characterization of hydroxamate siderophore produced by marine Vibrio harveyi.

    Science.gov (United States)

    Murugappan, R M; Aravinth, A; Karthikeyan, M

    2011-02-01

    In the present study, 22 different bacteria were isolated from open ocean water from the Gulf of Mannar, India. Of the 22 isolates, 4 were identified as Vibrio spp. (VM1, VM2, VM3 and VM4) and found to produce siderophores (iron-binding chelators) under iron-limited conditions. Different media were found to have an influence on siderophore production. Maximum siderophore production was observed with VM1 isolate in MM9 salts medium at 48 h of incubation. The isolate was confirmed as Vibrio harveyi based on 16S rRNA gene sequencing and phylogenetic analysis. Fourier-transform infrared (FTIR) and (1)H nuclear magnetic resonance (NMR) spectra revealed the hydroxamate nature of the siderophore produced. Further characterization of the siderophore revealed it to be of dihydroxamate nature, forming hexadentate ligands with Fe(III) ions. A narrow shift in ultraviolet (UV)-Vis spectrum was observed on photolysis due to ligand oxidation. Growth-promotion bioassay with Aeromonas hydrophila, Staphylococcus aureus and E. coli confirmed the iron-scavenging property of the siderophore produced by Vibrio harveyi.

  10. Sexual reproduction of Daphnia in a deep temperate reservoir: the phenology and genetics of male formation

    Czech Academy of Sciences Publication Activity Database

    Macháček, Jiří; Vaníčková, Ivana; Seďa, Jaromír; Cordellier, M.; Schwenk, K.

    2013-01-01

    Roč. 715, č. 1 (2013), s. 113-123 ISSN 0018-8158. [International Symposium on Cladocera /9./. Verbania-Palanza, 02.10.2011-08.10.2011] R&D Projects: GA ČR(CZ) GA206/09/1325 Institutional support: RVO:60077344 Keywords : Daphnia * reservoir population * male induction * clonal structure * microsatellite Subject RIV: DA - Hydrology ; Limnology Impact factor: 2.212, year: 2013

  11. Is the fatty acid composition of Daphnia galeata determined by the fatty acid composition of the ingested diet?

    NARCIS (Netherlands)

    Weers, P.M.M.; Siewertsen, K.; Gulati, R.D.

    1997-01-01

    1. The fatty acid (FA) composition of Daphnia galeata and their algal food was analysed and showed many similarities, however, some significant differences were also found in the relative abundance of the FA C16:4 omega 3 and docosahexaenoic acid (DHA). Their relative abundances were much lower in

  12. Bioconcentration of the antidepressant fluoxetine and its effects on the physiological and biochemical status in Daphnia magna.

    Science.gov (United States)

    Ding, Jiannan; Zou, Hua; Liu, Qingqing; Zhang, Shanshan; Mamitiana Razanajatovo, Roger

    2017-08-01

    The aim of this study was to evaluate the bioconcentration potential of fluoxetine and its biological effects in Daphnia magna. After 48h of waterborne exposure, the bioconcentration of fluoxetine in D. magna was determined to be 460.61 and 174.41Lkg -1 for nominal exposure concentrations of 0.5 and 5µgL -1 , respectively. Moreover, various biological endpoints, including physiological responses (filtration and ingestion rates), enzymatic biomarkers related to neurotoxicity [acetylcholinesterase (AChE)] and antioxidant defense [superoxide dismutase (SOD)], and an oxidative stress damage marker [malondialdehyde (MDA)], were assessed. Fluoxetine exposure increased the filtration rate of daphnia, while the ingestion rate was not obviously modified. AChE activity was significantly inhibited, highlighting the neurotoxicity of fluoxetine on D. magna. However, with some alterations in the SOD activity and MDA content, no obvious oxidative damage was observed in D. magna exposed to fluoxetine at the tested concentrations. These results indicate that fluoxetine can be accumulated and consequently induce physiological and biochemical perturbations in D. magna. Copyright © 2017. Published by Elsevier Inc.

  13. High temperatures and absence of light affect the hatching of resting eggs of Daphnia in the tropics

    Directory of Open Access Journals (Sweden)

    Thécia A.S.V. Paes

    2016-03-01

    Full Text Available Temperature and light are acknowledged as important factors for hatching of resting eggs. The knowledge of how they affect hatching rates of this type of egg is important for the comprehension of the consequences of warming waters in recolonization of aquatic ecosystems dependent on dormant populations. This study aimed at comparing the influence of different temperature and light conditions on hatching rates of Daphnia ambigua andDaphnia laevis resting eggs from tropical environments. The ephippia were collected in the sediment of three aquatic ecosystems, in southeastern Brazil. For each lake, the resting eggs were exposed to temperatures of 20, 24, 28 and 32 °C, under light (12 h photoperiod and dark conditions. The results showed that the absence of light and high temperatures have a negative influence on the hatching rates. Statistical differences for hatching rates were also found when comparing the studied ecosystems (ranging from 0.6 to 31%, indicating the importance of local environmental factors for diapause and maintenance of active populations.

  14. Distillation fraction-specific ecotoxicological evaluation of a paraffin-rich crude oil.

    Science.gov (United States)

    Erlacher, Elisabeth; Loibner, Andreas P; Kendler, Romana; Scherr, Kerstin E

    2013-03-01

    Crude oil is a complex mixture of petroleum hydrocarbons (PHC) with distinct chemical, physical and toxicological properties relevant for contaminated site risk assessment. Ecotoxicological effects of crude oil distillation fractions on luminescent bacteria (Vibrio fischeri), earthworms (Dendrobaena hortensis) and invertebrates (Heterocypris incongruens) were tested using two spiked soils and their elutriates. Fraction 2 (F2) had an equivalent carbon number (ECN) range of >10 to 16, and F3 from >16 to 39. F2 showed a substantially higher ecotoxicological effect than F3 for Vibrio and Dendrobaena. In contrast, severe inhibition of Heterocypris by the poorly soluble F3 is attributed to mechanical organ blockage. Immediate sequestration of PHC to the organic matter-rich soil effected reduced toxicity for all organisms. This study indicates that a more differentiated consideration (i) of PHC mixtures based on ECN range and (ii) of model soil properties employed for ecotoxicity testing should be included into PHC-contaminated site risk assessment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Multi-generational effects of propranolol on Daphnia magna at different environmental concentrations

    International Nuclear Information System (INIS)

    Jeong, Tae-Yong; Kim, Hyun Young; Kim, Sang Don

    2015-01-01

    To evaluate the effects of propranolol on Daphnia magna (D. magna), we employed a multi-generational exposure period for eight generations and an environmentally relevant low concentration with 1.5 ng/L, 0.2 μg/L and 26 μg/L to reflect a realistic exposure scenario. Physiological endpoints were checked, including growth, number of neonates, heart rate, frequency of abdominal appendage movement and malformation rate of neonates. In the results, growth and abdominal appendage movement were affected by environmental concentration during several generations, and the responses showed consistent tendencies of response increase with concentration increase. Heart rate was the only endpoint affected throughout all exposure generations. Inhibitory and acceleratory effects on heart rate, growth and abdominal appendage movement suggest that it is necessary to cover sub-lethal endpoints of non-targeted organisms in eco-toxicity study because the physiological responses were detected at much lower concentrations than the results of traditional toxicity tests, including environmental concentration. - Highlights: • Multi-generational exposure was conducted to evaluate the effect of propranolol on Daphnia magna. • Heart rate was the only endpoint affected throughout all exposure generations. • Growth and abdominal appendage movement were affected at environmental concentrations. • Time series fluctuations in responses appeared with no tendencies throughout all generations. • It is necessary to cover sub-organismal endpoints and long-term exposure in ecotoxicity test. - Heart rate, growth and abdominal appendage movement of D. magna were affected by the multigenerational exposure of propranolol at environmental levels.

  16. Mechanistic explanation of time-dependent cross-phenomenon based on quorum sensing: A case study of the mixture of sulfonamide and quorum sensing inhibitor to bioluminescence of Aliivibrio fischeri.

    Science.gov (United States)

    Sun, Haoyu; Pan, Yongzheng; Gu, Yue; Lin, Zhifen

    2018-07-15

    Cross-phenomenon in which the concentration-response curve (CRC) for a mixture crosses the CRC for the reference model has been identified in many studies, expressed as a heterogeneous pattern of joint toxic action. However, a mechanistic explanation of the cross-phenomenon has thus far been extremely insufficient. In this study, a time-dependent cross-phenomenon was observed, in which the cross-concentration range between the CRC for the mixture of sulfamethoxypyridazine (SMP) and (Z-)-4-Bromo-5-(bromomethylene)-2(5H)-furanone (C30) to the bioluminescence of Aliivibrio fischeri (A. fischeri) and the CRC for independent action model with 95% confidence bands varied from low-concentration to higher-concentration regions in a timely manner expressed the joint toxic action of the mixture changing with an increase of both concentration and time. Through investigating the time-dependent hormetic effects of SMP and C30 (by measuring the expression of protein mRNA, simulating the bioluminescent reaction and analyzing the toxic action), the underlying mechanism was as follows: SMP and C30 acted on the quorum sensing (QS) system of A. fischeri, which induced low-concentration stimulatory effects and high-concentration inhibitory effects; in the low-concentration region, the stimulatory effects of SMP and C30 made the mixture produce a synergistic stimulation on the bioluminescence; thus, the joint toxic action exhibited antagonism. In the high-concentration region, the inhibitory effects of SMP and C30 in the mixture caused a double block in the loop circuit of the QS system; thus, the joint toxic action exhibited synergism. With the increase of time, these stimulatory and inhibitory effects of SMP and C30 were changed by the variation of the QS system at different growth phases, resulting in the time-dependent cross-phenomenon. This study proposes an induced mechanism for time-dependent cross-phenomenon based on QS, which may provide new insight into the mechanistic

  17. Effects of different doses of skt-b vibrio probiotic bacteria addition on survival and growth rate of tiger shrimp (Penaeus monodon larva

    Directory of Open Access Journals (Sweden)

    . Widanarni

    2010-01-01

    Full Text Available Probiotic bacteria has been widely used as biocontrol agents in tiger shrimp hatcheries.  Vibrio SKT-b is one of the probiotic bacteria candidates that could suppressed the growth of pathogenic bacteria Vibrio harveyi and could increase survival rate of tiger shrimp larva. This experiment was carried out to study the effects of probiotic bacteria SKT-b Vibrio addition at different doses on survival and growth rate of tiger shrimp larva.  Experiment was conducted with five treatments and three replications, consisted of SKT-b Vibrio probiotic bacteria addition at the doses of 103 CFU/ml, 104 CFU/ml, 105 CFU/ml, and 106 CFU/ml and control (0 CFU/ml.  Results showed that optimum dose of probiotic bacteria for tiger shrimp was 104 CFU/ml with a survival rate of 94.67%. However, the addition of probiotic bacteria at this particular dose did not significantly increase shrimp growth rate as compared with control. Key words: Probiotic bacteria, SKT-b Vibrio, doses, tiger shrimp larva   ABSTRAK Bakteri probiotik telah banyak digunakan sebagai agen biokontrol dalam pembenihan udang windu.  Vibrio SKT-b merupakan salah satu jenis bakteri kandidat probiotik yang telah diuji dapat menekan pertumbuhan bakteri patogen Vibrio harveyi dan dapat meningkatkan kelangsungan hidup larva udang windu.  Tujuan dari penelitian ini adalah untuk mengetahui pengaruh pemberian bakteri probiotik Vibrio SKT-b dengan dosis yang berbeda terhadap kelangsungan hidup dan pertumbuhan larva udang windu. Penelitian ini dilakukan dalam 5 perlakuan dengan masing-masing 3 ulangan, yaitu penambahan bakteri probiotik Vibrio SKT-b dengan dosis 103 CFU/ml, 104 CFU/ml, 105 CFU/ml, dan 106 CFU/ml dan kontrol (0 CFU/ml.  Hasil penelitian menunjukkan bahwa dosis optimal untuk larva udang windu adalah 104 CFU/ml dengan nilai kelangsungan hidup 94,67%. Namun, pemberian bakteri probiotik tersebut belum menghasilkan pertumbuhan yang berbeda nyata dengan kontrol. Kata kunci: Bakteri probiotik

  18. Survival of Vibrio cholerae in industrially polluted water, with ...

    African Journals Online (AJOL)

    containing industrial effluents. The effect of iron as well as pH on the survival of Vibrio cholerae (non-O1, El Tor and classical strains) in water samples from 12 points, where selected industrial effluents were discharged into rivers, was studied.

  19. How cyclophosphamide at environmentally relevant concentration influences Daphnia magna life history and its proteome.

    Directory of Open Access Journals (Sweden)

    Małgorzata Grzesiuk

    Full Text Available The waste of commonly used medicines is known to contaminate freshwater ecosystems. Pharmaceuticals can be toxic, mutagenic, or modifying to freshwater organisms even at low concentrations if consider their permanent presence in the environment. Chemotherapeutics used to treat cancer, and in particular alkylating agents, contribute significantly to this form of pollution, the latter introducing cytotoxic and/or mutagenic lesions to the DNA and RNA of organisms which can be disruptive to their cells. The aim of the present study was to investigate the influence of the alkylating anticancer agent cyclophosphamide (CP on Daphnia magna clones. We evaluated the life history parameters and protein profiles of this crustacean following exposure to environmentally relevant CP concentration of 10 ng L-1. Even at this low concentration, the alkylating agent caused modification of the life history parameters and proteome profile of the Daphnia. These changes were clone-specific and involved growth rate, age at first reproduction, neonate number, and proteins related to cell cycle and redox state regulation. The disturbance caused by pharmaceuticals contaminating freshwater ecosystem is probably weaker and unlikely to be cytotoxic in character due to the high dilution of these substances in the water. However, our results indicate that prolonged exposure of organisms to these toxins may lead to modifications on the organismal and molecular levels with unpredictable significance for the entire ecosystem.

  20. The rate-size trade-off structures intraspecific variation in Daphnia ambigua life history parameters.

    Science.gov (United States)

    DeLong, John P; Hanley, Torrance C

    2013-01-01

    The identification of trade-offs is necessary for understanding the evolution and maintenance of diversity. Here we employ the supply-demand (SD) body size optimization model to predict a trade-off between asymptotic body size and growth rate. We use the SD model to quantitatively predict the slope of the relationship between asymptotic body size and growth rate under high and low food regimes and then test the predictions against observations for Daphnia ambigua. Close quantitative agreement between observed and predicted slopes at both food levels lends support to the model and confirms that a 'rate-size' trade-off structures life history variation in this population. In contrast to classic life history expectations, growth and reproduction were positively correlated after controlling for the rate-size trade-off. We included 12 Daphnia clones in our study, but clone identity explained only some of the variation in life history traits. We also tested the hypothesis that growth rate would be positively related to intergenic spacer length (i.e. the growth rate hypothesis) across clones, but we found that clones with intermediate intergenic spacer lengths had larger asymptotic sizes and slower growth rates. Our results strongly support a resource-based optimization of body size following the SD model. Furthermore, because some resource allocation decisions necessarily precede others, understanding interdependent life history traits may require a more nested approach.