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Sample records for pseudomonas veronii 2e

  1. Biosynthesis of gold nanoparticles by Pseudomonas veronii AS41G inhabiting Annona squamosa L.

    Science.gov (United States)

    Baker, Syed; Satish, Sreedharamurthy

    2015-11-05

    Biogenic principles to nanotechnology have generated tremendous attention in recent past owing eco friendly benign process for synthesis of nanoparticles. Present investigation reports extracellular synthesis of gold nanoparticles using cell free supernatant of Pseudomonas veronii AS 41G, a novel endophyte isolated from Annona squamosa L. Gold nanoparticles formation was confirmed with UV-Visible spectrophotometer. FTIR analysis predicted various functional groups responsible for reduction of metal salts and stabilization of gold nanoparticles. Nanoparticles were crystalline in nature as shown in XRD pattern. TEM analysis revealed morphological characteristics of nanoparticles with different size. Thus the present study attributes for facile process for synthesis of gold nanoparticles as an alternative for conventional methods. The study also highlights the new role of novel bacterium Pseudomonas veronii AS41G which will be very valuable as a record for the researchers working on it. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Degradation of Benzene by Pseudomonas veronii 1YdBTEX2 and 1YB2 Is Catalyzed by Enzymes Encoded in Distinct Catabolism Gene Clusters.

    Science.gov (United States)

    de Lima-Morales, Daiana; Chaves-Moreno, Diego; Wos-Oxley, Melissa L; Jáuregui, Ruy; Vilchez-Vargas, Ramiro; Pieper, Dietmar H

    2015-10-16

    Pseudomonas veronii 1YdBTEX2, a benzene and toluene degrader, and Pseudomonas veronii 1YB2, a benzene degrader, have previously been shown to be key players in a benzene-contaminated site. These strains harbor unique catabolic pathways for the degradation of benzene comprising a gene cluster encoding an isopropylbenzene dioxygenase where genes encoding downstream enzymes were interrupted by stop codons. Extradiol dioxygenases were recruited from gene clusters comprising genes encoding a 2-hydroxymuconic semialdehyde dehydrogenase necessary for benzene degradation but typically absent from isopropylbenzene dioxygenase-encoding gene clusters. The benzene dihydrodiol dehydrogenase-encoding gene was not clustered with any other aromatic degradation genes, and the encoded protein was only distantly related to dehydrogenases of aromatic degradation pathways. The involvement of the different gene clusters in the degradation pathways was suggested by real-time quantitative reverse transcription PCR. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. The Genome of the Toluene-Degrading Pseudomonas veronii Strain 1YdBTEX2 and Its Differential Gene Expression in Contaminated Sand.

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    Morales, Marian; Sentchilo, Vladimir; Bertelli, Claire; Komljenovic, Andrea; Kryuchkova-Mostacci, Nadezda; Bourdilloud, Audrey; Linke, Burkhard; Goesmann, Alexander; Harshman, Keith; Segers, Francisca; Delapierre, Fabien; Fiorucci, Damien; Seppey, Mathieu; Trofimenco, Evgeniya; Berra, Pauline; El Taher, Athimed; Loiseau, Chloé; Roggero, Dejan; Sulfiotti, Madeleine; Etienne, Angela; Ruiz Buendia, Gustavo; Pillard, Loïc; Escoriza, Angelique; Moritz, Roxane; Schneider, Cedric; Alfonso, Esteban; Ben Jeddou, Fatma; Selmoni, Oliver; Resch, Gregory; Greub, Gilbert; Emery, Olivier; Dubey, Manupriyam; Pillonel, Trestan; Robinson-Rechavi, Marc; van der Meer, Jan Roelof

    2016-01-01

    The natural restoration of soils polluted by aromatic hydrocarbons such as benzene, toluene, ethylbenzene and m- and p-xylene (BTEX) may be accelerated by inoculation of specific biodegraders (bioaugmentation). Bioaugmentation mainly involves introducing bacteria that deploy their metabolic properties and adaptation potential to survive and propagate in the contaminated environment by degrading the pollutant. In order to better understand the adaptive response of cells during a transition to contaminated material, we analyzed here the genome and short-term (1 h) changes in genome-wide gene expression of the BTEX-degrading bacterium Pseudomonas veronii 1YdBTEX2 in non-sterile soil and liquid medium, both in presence or absence of toluene. We obtained a gapless genome sequence of P. veronii 1YdBTEX2 covering three individual replicons with a total size of 8 Mb, two of which are largely unrelated to current known bacterial replicons. One-hour exposure to toluene, both in soil and liquid, triggered massive transcription (up to 208-fold induction) of multiple gene clusters, such as toluene degradation pathway(s), chemotaxis and toluene efflux pumps. This clearly underlines their key role in the adaptive response to toluene. In comparison to liquid medium, cells in soil drastically changed expression of genes involved in membrane functioning (e.g., lipid composition, lipid metabolism, cell fatty acid synthesis), osmotic stress response (e.g., polyamine or trehalose synthesis, uptake of potassium) and putrescine metabolism, highlighting the immediate response mechanisms of P. veronii 1YdBTEX2 for successful establishment in polluted soil.

  4. The Genome of the Toluene-Degrading Pseudomonas veronii Strain 1YdBTEX2 and Its Differential Gene Expression in Contaminated Sand.

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    Marian Morales

    Full Text Available The natural restoration of soils polluted by aromatic hydrocarbons such as benzene, toluene, ethylbenzene and m- and p-xylene (BTEX may be accelerated by inoculation of specific biodegraders (bioaugmentation. Bioaugmentation mainly involves introducing bacteria that deploy their metabolic properties and adaptation potential to survive and propagate in the contaminated environment by degrading the pollutant. In order to better understand the adaptive response of cells during a transition to contaminated material, we analyzed here the genome and short-term (1 h changes in genome-wide gene expression of the BTEX-degrading bacterium Pseudomonas veronii 1YdBTEX2 in non-sterile soil and liquid medium, both in presence or absence of toluene. We obtained a gapless genome sequence of P. veronii 1YdBTEX2 covering three individual replicons with a total size of 8 Mb, two of which are largely unrelated to current known bacterial replicons. One-hour exposure to toluene, both in soil and liquid, triggered massive transcription (up to 208-fold induction of multiple gene clusters, such as toluene degradation pathway(s, chemotaxis and toluene efflux pumps. This clearly underlines their key role in the adaptive response to toluene. In comparison to liquid medium, cells in soil drastically changed expression of genes involved in membrane functioning (e.g., lipid composition, lipid metabolism, cell fatty acid synthesis, osmotic stress response (e.g., polyamine or trehalose synthesis, uptake of potassium and putrescine metabolism, highlighting the immediate response mechanisms of P. veronii 1YdBTEX2 for successful establishment in polluted soil.

  5. Producción de ácido indol-3-acético por Pseudomonas veronii R4 y formación de raíces en hojas de vid “Thompson seedless” in vitro

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    María F. Peñafiel-Jaramillo

    2016-06-01

    Full Text Available Rizobacterias con actividad antagonista son empleadas a problemas patológicos y promueven el desarrollo de tejido radicular de especies vegetales El objetivo del estudio fue evaluar la capacidad en síntesis de ácido indol-3-acetico (AIA y la formación de raíces en hojas de vid “Thompson Seedless”, por el empleo de Pseudomonas veronii R4 in vitro. La bacteria, fue incubada en medio mínimo M9 y se verificó la producción de AIA a 24, 48 y 72 h de muestreo, los sobrenadantes fueron analizandos por HPLC. Peciolos de hojas de “Thompson Seedless” fueron sumergidos por 5 min, en el tampón PBS con P. veronii R4 a (1.5 x 109 células mL-1, y evaluados a los 32 días post-inoculación. Los tratamientos fueron sujetos al análisis de varianza por DCA. Los sobrenadantes muestreados a 72 h, del cultivo de líquido con P. veronii R4, se obtuvo los mayores niveles de AIA entre 0.0231 a 0.0245 mM, al emplear 5 a 10 mM del precursor L-triptofano, del sobrenadante obtenido de P. fluorescens CHA0 la producción de AIA con 0.0174 mM a 10 mM de L-triptofano. Se obtuvo la regeneración del sistema radicular en los peciolos de hojas de “Thompson Seedless”, con un promedio de 14 raíces/planta bajo la aplicación de P. veronii R4. Estos resultados preliminares realzan la importancia de la cepa nativa P. veronii R4, que se estaría proyectando para futuras investigaciones de su empleo en condición de invernadero al desarrollo del sistema radicular en “Thompson Seedless”.

  6. Producción de ácido indol-3-acético por Pseudomonas veronii R4 y formación de raíces en hojas de vid “Thompson seedless” in vitro

    Directory of Open Access Journals (Sweden)

    Maria Peñafiel Jaramillo

    2016-07-01

    Full Text Available Rizobacterias con actividad antagonista son empleadas a problemas patológicos y promueven el desarrollo de tejido radicular de especies vegetales El objetivo del estudio fue evaluar la capacidad en síntesis de ácido indol-3-acetico (AIA y la formación de raíces en hojas de vid “Thompson Seedless”, por el empleo de Pseudomonas veronii R4 in vitro. La bacteria, fue incubada en medio mínimo M9 y se verificó la producción de AIA a 24, 48 y 72 h de muestreo, los sobrenadantes fueron analizandos por HPLC. Peciolos de hojas de “Thompson Seedless” fueron sumergidos por 5 min, en el tampón PBS con P. veronii R4 a (1.5 x 109 células mL-1, y evaluados a los 32 días post-inoculación. Los tratamientos fueron sujetos al análisis de varianza por DCA. Los sobrenadantes muestreados a 72 h, del cultivo de líquido con P. veronii R4, se obtuvo los mayores niveles de AIA entre 0.0231 a 0.0245 mM, al emplear 5 a 10 mM del precursor L-triptofano, del sobrenadante obtenido de P. fluorescens CHA0 la producción de AIA con 0.0174 mM a 10 mM de L-triptofano. Se obtuvo la regeneración del sistema radicular en los peciolos de hojas de “Thompson Seedless”, con un promedio de 14 raíces/planta bajo la aplicación de P. veronii R4. Estos resultados preliminares realzan la importancia de la cepa nativa P. veronii R4, que se estaría proyectando para futuras investigaciones de su empleo en condición de invernadero al desarrollo del sistema radicular en “Thompson Seedless”.

  7. Antimicrobial susceptibility patterns of Aeromonas jandaei, A. schubertii, A. trota, and A. veronii biotype veronii.

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    Overman, T L; Janda, J M

    1999-03-01

    Fifty-six isolates of four Aeromonas species, which have been documented as causative agents of human infections or isolated from human clinical specimens, were subjected to antimicrobial susceptibility testing using a MicroScan WalkAway conventional (overnight incubation) gram-negative panel. The four species tested and the number of isolates of each were as follows: Aeromonas jandaei, 17; A. schubertii, 12; A. trota, 15; and A. veronii biotype veronii, 12. All isolates of A. trota were susceptible to all antimicrobial agents tested, except cefazolin (20% of isolates were resistant) and cefoxitin (13% of isolates were resistant). All isolates of A. schubertii and A. veronii biotype veronii, as well as 88% of A. jandaei isolates, were resistant to ampicillin. Resistance to ampicillin-sulbactam ranged from 25% of A. schubertii strains to 100% of A. veronii biotype veronii strains. Cefazolin resistance ranged from 17% of A. veronii biotype veronii isolates to 59% of A. jandaei isolates. Imipenem resistance was detected in 65% of A. jandaei strains and 67% of A. veronii biotype veronii strains. A. jandaei displayed resistance to piperacillin and ticarcillin in 53 and 71% of the isolates, respectively. A. veronii biotype veronii strains were 100% susceptible to piperacillin and 100% resistant to ticarcillin. These antibiogram data may be useful in establishing the identification of these four species when members of the genus Aeromonas are isolated from human clinical sources.

  8. Lactobacillus plantarum (VR1) isolated from an ayurvedic medicine (Kutajarista) ameliorates in vitro cellular damage caused by Aeromonas veronii.

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    Kumar, Himanshu; Rangrez, Ashraf Y; Dayananda, Kannayakanahalli M; Atre, Ashwini N; Patole, Milind S; Shouche, Yogesh S

    2011-06-27

    Lactobacillus plantarum is considered as a safe and effective probiotic microorganism. Among various sources of isolation, traditionally fermented foods are considered to be rich in Lactobacillus spp., which can be exploited for their probiotic attribute. Antibacterial property of L. plantarum has been demonstrated against various enteric pathogens in both in vitro and in vivo systems. This study was aimed at characterizing L. plantarum isolated from Kutajarista, an ayurvedic fermented biomedicine, and assessing its antagonistic property against a common enteropathogen Aeromonas veronii. We report the isolation of L. plantarum (VR1) from Kutajarista, and efficacy of its cell free supernatant (CFS) in amelioration of cytotoxicity caused by Aeromonas veronii. On the part of probiotic attributes, VR1 was tolerant to pH 2, 0.3% bile salts and simulated gastric juice. Additionally, VR1 also exhibited adhesive property to human intestinal HT-29 cell line. Furthermore, CFS of VR1 was antibacterial to enteric pathogens like Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Aeromonas veronii and clinical isolates of P. aeruginosa and E. coli. Detailed study regarding the effect of VR1 CFS on A. veronii cytotoxicity showed a significant decrease in vacuole formation and detrimental cellular changes in Vero cells. On the other hand, A. veronii CFS caused disruption of tight junction proteins ZO-1 and actin in MDCK cell line, which was prevented by pre-incubation with CFS of VR1. This is the first study to report isolation of L. plantarum (VR1) from Kutajarista and characterisation for its probiotic attributes. Our study demonstrates the antagonistic property of VR1 to A. veronii and effect of VR1 CFS in reduction of cellular damage caused by A. veronii in both Vero and MDCK cell lines. © 2011 Kumar et al; licensee BioMed Central Ltd.

  9. Lactobacillus plantarum (VR1 isolated from an Ayurvedic medicine (Kutajarista ameliorates in vitro cellular damage caused by Aeromonas veronii

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    Patole Milind S

    2011-06-01

    Full Text Available Abstract Background Lactobacillus plantarum is considered as a safe and effective probiotic microorganism. Among various sources of isolation, traditionally fermented foods are considered to be rich in Lactobacillus spp., which can be exploited for their probiotic attribute. Antibacterial property of L. plantarum has been demonstrated against various enteric pathogens in both in vitro and in vivo systems. This study was aimed at characterizing L. plantarum isolated from Kutajarista, an ayurvedic fermented biomedicine, and assessing its antagonistic property against a common enteropathogen Aeromonas veronii. Results We report the isolation of L. plantarum (VR1 from Kutajarista, and efficacy of its cell free supernatant (CFS in amelioration of cytotoxicity caused by Aeromonas veronii. On the part of probiotic attributes, VR1 was tolerant to pH 2, 0.3% bile salts and simulated gastric juice. Additionally, VR1 also exhibited adhesive property to human intestinal HT-29 cell line. Furthermore, CFS of VR1 was antibacterial to enteric pathogens like Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Aeromonas veronii and clinical isolates of P. aeruginosa and E. coli. Detailed study regarding the effect of VR1 CFS on A. veronii cytotoxicity showed a significant decrease in vacuole formation and detrimental cellular changes in Vero cells. On the other hand, A. veronii CFS caused disruption of tight junction proteins ZO-1 and actin in MDCK cell line, which was prevented by pre-incubation with CFS of VR1. Conclusions This is the first study to report isolation of L. plantarum (VR1 from Kutajarista and characterisation for its probiotic attributes. Our study demonstrates the antagonistic property of VR1 to A. veronii and effect of VR1 CFS in reduction of cellular damage caused by A. veronii in both Vero and MDCK cell lines.

  10. Ingested Blood Contributes to the Specificity of the Symbiosis of Aeromonas veronii Biovar Sobria and Hirudo medicinalis, the Medicinal Leech

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    Indergand, Stefan; Graf, Joerg

    2000-01-01

    Hirudo medicinalis, the medicinal leech, usually carries in its digestive tract a pure culture of Aeromonas veronii bv. sobria. Such specificity is unusual for digestive tracts that are normally colonized by a complex microbial consortium. Important questions for the symbiotic interaction and for the medical application after microvascular surgery are whether other bacteria can proliferate or at least persist in the digestive tract of H. medicinalis and what factors contribute to the reported specificity. Using a colonization assay, we were able to compare experimentally the ability of clinical isolates and of a symbiotic strain to colonize H. medicinalis. The symbiotic A. veronii bv. sobria strain proliferated well and persisted for at least 7 days inside the digestive tract. In contrast, the proliferation of Pseudomonas aeruginosa and Staphylococcus aureus was inhibited inside the animal compared to growth in the in vitro control, indicating that the ingested blood was modified within the digestive tract. However, both strains were able to persist in the digestive tract for at least 7 days. For an Escherichia coli strain, the viable counts decreased approximately 1,000-fold within 42 h. The decrease of viable E. coli could be prevented by interfering with the activation of the membrane-attack complex of the complement system that is present in blood. This suggests that the membrane-attack complex remained active inside H. medicinalis and prevented the proliferation of sensitive bacteria. Thus, antimicrobial properties of the ingested vertebrate blood contribute to the specificity of the A. veronii-H. medicinalis symbiosis, in addition to modifications of the blood inside the digestive tract of H. medicinalis. PMID:11055917

  11. Clinical isolates of Aeromonas veronii biovar veronii harbor a nonfunctional gene similar to the thermostable direct hemolysin-related hemolysin (trh) gene of Vibrio parahaemolyticus.

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    Raghunath, Pendru; Maiti, Biswajit; Shekar, Malathi; Karunasagar, Iddya; Karunasagar, Indrani

    2010-06-01

    Thermostable direct hemolysin-related hemolysin encoded by the trh gene is considered a major virulence factor in the pathogenesis of Vibrio parahaemolyticus infections. In this study, we report the presence of a trh homolog in three clinical isolates of Aeromonas veronii biovar veronii. The presence of a trh homolog in these strains of A. veronii was confirmed by PCR, followed by cloning, sequencing and colony hybridization using a digoxigenin-labelled probe. DNA sequence analysis revealed that the A. veronii trh gene had an identity of 99% and 84% to the trh1 and trh2 genes of V. parahaemolyticus, respectively. However, the expression of a trh-like gene in A. veronii could not be detected by reverse transcription PCR. Hence, the role of the gene product in the virulence of A. veronii strains is not clear. Further, these A. veronii isolates were negative for the ure gene encoding urease and the transposase gene by PCR. These genes are part of the trh gene cluster in V. parahaemolyticus. However, the presence of a trh homolog in a pathogen other than V. parahaemolyticus points to the fact that detection of the trh gene in stool samples, seafood enrichments or environmental samples does not always imply that trh-carrying V. parahaemolyticus are present.

  12. Characterization of Virulence Properties of Aeromonas veronii Isolated from Diseased Gibel Carp (Carassius gibelio

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    Jingjing Sun

    2016-04-01

    Full Text Available Aeromonas veronii is a kind of opportunistic pathogen to fish and humans, significantly impending aquaculture production. Recently, we isolated two A. veronii strains, named GYC1 and GYC2, from diseased Gibel carp (Carassius gibelio in China. Based on gyrB (DNA gyrase B subunit genes of GYC1 and GYC2, the constructed phylogenetic tree showed that the two strains were clustered with A. veronii. Sixteen virulence genes related to the pathogenicity of Aeromonas spp. were subjected to PCR assay. The genes of ompAI, ompAII, lafA, act, aer, fla, gcaT and acg were detected in the two strains, while genes of hly, ahp, lip, ast and alt were not detected. Additionally, genes eprCAI, ela and exu were only detected in the strain GYC1. Furthermore, the results of extracellular enzyme analysis revealed that the two isolates can produce hemolysin, caseinase, esterase, amylase and lecithinase, which were closely related to the pathogenicity of the two strains. However, the results showed that there was no gelatinase activity in either strain. According to the antibiotic resistant assay, the two strains were sensitive to cephalosporins and aminoglycosides, while they were resistant to penicillins and quinolones. Through this study, the virulence characteristics, including virulence genes and extracellular enzymes, the pathogenicity of A. veronii was clarified, enhancing the understanding about this pathogenic bacterium and providing the theoretical basis in disease control.

  13. Complex evolutionary history of the Aeromonas veronii group revealed by host interaction and DNA sequence data.

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    Adam C Silver

    Full Text Available Aeromonas veronii biovar sobria, Aeromonas veronii biovar veronii, and Aeromonas allosaccharophila are a closely related group of organisms, the Aeromonas veronii Group, that inhabit a wide range of host animals as a symbiont or pathogen. In this study, the ability of various strains to colonize the medicinal leech as a model for beneficial symbiosis and to kill wax worm larvae as a model for virulence was determined. Isolates cultured from the leech out-competed other strains in the leech model, while most strains were virulent in the wax worms. Three housekeeping genes, recA, dnaJ and gyrB, the gene encoding chitinase, chiA, and four loci associated with the type three secretion system, ascV, ascFG, aexT, and aexU were sequenced. The phylogenetic reconstruction failed to produce one consensus tree that was compatible with most of the individual genes. The Approximately Unbiased test and the Genetic Algorithm for Recombination Detection both provided further support for differing evolutionary histories among this group of genes. Two contrasting tests detected recombination within aexU, ascFG, ascV, dnaJ, and gyrB but not in aexT or chiA. Quartet decomposition analysis indicated a complex recent evolutionary history for these strains with a high frequency of horizontal gene transfer between several but not among all strains. In this study we demonstrate that at least for some strains, horizontal gene transfer occurs at a sufficient frequency to blur the signal from vertically inherited genes, despite strains being adapted to distinct niches. Simply increasing the number of genes included in the analysis is unlikely to overcome this challenge in organisms that occupy multiple niches and can exchange DNA between strains specialized to different niches. Instead, the detection of genes critical in the adaptation to specific niches may help to reveal the physiological specialization of these strains.

  14. Small Protein B upregulates sensor kinase bvgS expression in Aeromonas veronii

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    Zhu eLiu

    2015-06-01

    Full Text Available Earlier studies reveal that Small Protein B (SmpB, a class of well-conserved tmRNA-binding proteins, is essential for the trans-translation process, which functions as a system for translation surveillance and ribosome rescue. Here, we report a previously unrecognized mechanism by which SmpB alone positively regulates the expression of a sensor kinase, BvgS, in Aeromonas veronii. A reporter plasmid was constructed in which the promoter of bvgS was used to control the expression of the enhanced green fluorescent protein (eGFP gene. When the reporter plasmid was co-transformed with a SmpB expression construct into E. coli, the relative fluorescence intensity increased about 3-fold. Transformation with a truncated form of smpB gene showed that the C-terminus had little effect, while N-terminus unexpectedly increased eGFP production. Next, a series of SmpB mutants were generated by site-directed mutagenesis. When the mutants SmpB (G11S or SmpB (E32AG was used in the experiment, eGFP expression dropped significantly compared with that of wild type SmpB. Further,purified SmpB was shown to bind the promoter regions of bvgS in the agarose gel retardation assay. Quantitative RT-PCR analysis showed that eGFP transcript levels increased approximately 25-fold in the presence of SmpB. Likewise, bvgS transcripts decreased significantly in smpB knockout A. veronii. Similar to BvgS inhibition, smpB knockout in A. veronii displayed a reduced capability in salt tolerance. Collectively, the data presented here will facilitate a deeper understanding of SmpB-mediated regulatory circuits as a transcriptional factor in A. veronii.

  15. Biochemical and molecular characterization of tetracycline-resistant Aeromonas veronii isolates from catfish.

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    Nawaz, Mohamed; Sung, Kidon; Khan, Saeed A; Khan, Ashraf A; Steele, Roger

    2006-10-01

    Eighty-one tetracycline-resistant Aeromonas sp. strains were isolated from farm-raised catfish. Morphological and biochemical characteristics indicated that 23 of the 81 aeromonads were Aeromonas hydrophila, 7 isolates were Aeromonas trota, 6 isolates were Aeromonas caviae, 42 isolates were Aeromonas veronii, and 3 isolates were Aeromonas jandaei. However, the AluI and MboI restriction fragment length polymorphism (RFLP) patterns of the PCR-amplified 1.4-kb 16S rRNA gene from all 81 tetracycline-resistant aeromonads from catfish were identical to the RFLP banding patterns of A. veronii ATCC 35626, indicating that all 81 isolates were strains of A. veronii. A multiplex PCR assay successfully amplified the 5 tetracycline-resistant genes (tetA to E) from the genomic DNA of all 81 isolates. The assay determined that tetE was the dominant gene occurring in 73/81 (90.0%) of the aeromonads. Plasmids (2.0 to 20 kb) were isolated from 33 of the 81 isolates. Dendrogram analysis of the SpeI pulsed-field gel electrophoresis identified 15 distinct macrorestriction patterns among the isolates. Our results indicate the need for use of 16S rRNA in the identification of Aeromonas spp. and the prevalence of catfish as a reservoir of tet genes.

  16. Carbapenemase-Producing Aeromonas veronii Disseminated in the Environment of an Equine Specialty Hospital.

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    Adams, Rachael J; Mathys, Dimitria A; Mollenkopf, Dixie F; Whittle, Andrea; Daniels, Joshua B; Wittum, Thomas E

    2017-06-01

    The emergence of bacterial resistance to carbapenem antibiotics is an urgent public health threat. Carbapenem drugs are a last resort treatment option for life-threatening infections. The frequent use of broad-spectrum antibiotics to treat hospitalized patients provides significant selection pressure favoring the emergence and dissemination of resistant organisms, including carbapenem-resistant Enterobacteriaceae (CRE). CREs have been reported in animal populations, but only rarely in horses. Our objective was to determine the prevalence of CRE in the environment of a referral equine specialty hospital. Environmental samples were collected on seven different sampling dates. Four clonal carbapenemase-producing Aeromonas veronii were recovered from 315 sampled surfaces (1.3%). All four isolates harbored the carbapenemase-producing, metallo-β-lactamase gene blacphA, although corresponding minimum inhibitory concentrations were within the susceptible range for imipenem and meropenem. All had an identical multilocus sequence type with a previously unreported allelic profile and contained multiple plasmids. To our knowledge, this recovery of blacphA-harboring A. veronii is the first report of carbapenemase-producing bacteria in the environment of an equine veterinary hospital. However, the low recovery rate suggests that environmental contamination is uncommon. Appropriate hospital cleaning and disinfection protocols are necessary to maintain a low risk of contamination for patients and personnel.

  17. A Chitinase from Aeromonas veronii CD3 with the Potential to Control Myxozoan Disease

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    Liu, Yuchun; Zhou, Zhigang; Miao, Wei; Zhang, Yuting; Cao, Yanan; He, Suxu; Bai, Dongqing; Yao, Bin

    2011-01-01

    Background The class Myxosporea encompasses about 2,400 species, most of which are parasites of fish and cause serious damage in aquaculture. Due to the concerns about food safety issues and limited knowledge of Myxozoa life cycle and fish immune system, no chemicals, antibiotics or immune modulators are available to control myxozoa infection. Therefore, little can be done once Myxozoa establishment has occurred. Methodology/Principal Findings In this paper we isolated Aeromonas veronii CD3 with significant myxospore shell valve-degrading ability from pond sediment. A 3,057-bp full-length chitinase gene was consequently cloned, and the corresponding mature, recombinant chitinase (ChiCD3) produced by Escherichia coli had substantial chitinase activity. The deduced sequence of ChiCD3 contained one catalytic domain, two chitin-binding domains, and one putative signal peptide. ChiCD3 had an optimal activity at 50°C and pH 6.0, and retained more than 50% of its optimal activity under warm water aquaculture conditions (∼30°C and pH ∼7.0). After incubation with ChiCD3, 38.0±4.8% of the myxospores had damaged shell valves, whereas myxospores incubated with commercially available chitinases remained intact. Conclusion/Significance This study reveals a new strategy to control myxozoan disease. ChiCD3 that has capacity to damage the shell valve of myxospores can be supplemented into fish feed and used to control Myxozoa-induced diseases specifically. PMID:22205999

  18. Engineering Pseudomonas protegens Pf-5 for nitrogen fixation and its application to improve plant growth under nitrogen-deficient conditions.

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    Lorena Setten

    Full Text Available Nitrogen is the second most critical factor for crop production after water. In this study, the beneficial rhizobacterium Pseudomonas protegens Pf-5 was genetically modified to fix nitrogen using the genes encoding the nitrogenase of Pseudomonas stutzeri A1501 via the X940 cosmid. Pf-5 X940 was able to grow in L medium without nitrogen, displayed high nitrogenase activity and released significant quantities of ammonium to the medium. Pf-5 X940 also showed constitutive expression and enzymatic activity of nitrogenase in ammonium medium or in nitrogen-free medium, suggesting a constitutive nitrogen fixation. Similar to Pseudomonas protegens Pf-5, Pseudomonas putida, Pseudomonas veronii and Pseudomonas taetrolens but not Pseudomonas balearica and Pseudomonas stutzeri transformed with cosmid X940 showed constitutive nitrogenase activity and high ammonium production, suggesting that this phenotype depends on the genome context and that this technology to obtain nitrogen-fixing bacteria is not restricted to Pf-5. Interestingly, inoculation of Arabidopsis, alfalfa, tall fescue and maize with Pf-5 X940 increased the ammonium concentration in soil and plant productivity under nitrogen-deficient conditions. In conclusion, these results open the way to the production of effective recombinant inoculants for nitrogen fixation on a wide range of crops.

  19. Oral immunization with recombinant Lactobacillus casei expressing OmpAI confers protection against Aeromonas veronii challenge in common carp, Cyprinus carpio.

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    Zhang, Dong-Xing; Kang, Yuan-Huan; Chen, Long; Siddiqui, Shahrood Ahmed; Wang, Chun-Feng; Qian, Ai-Dong; Shan, Xiao-Feng

    2017-11-16

    Aeromonas veronii is a gram-negative pathogen capable of infecting both fish and mammals, including humans, and natural infection in fish results in irreparable damage to the aquaculture industry. Lactic acid bacteria (LAB) have a number of properties that make them attractive candidates as delivery vehicles for presentation to the mucosa sites of compounds with pharmaceutical interest, in particular vaccines. In this study, we generated two recombinant Lactobacillus casei (surface-displayed or secretory) expressing the OmpAI of A.veronii and evaluated the effect on immune responses in fish model. A 1022 bp gene fragment of the 42 kDa OmpAI antigen of A.veronii was cloned into pPG-1 (surface-displayed) and pPG-2 (secretory) and electrotransformed into Lactobacillus casei CC16. The recombinant plasmid in L.casei could be stably inherited over 50 generations, and production of OmpAI protein had slight limited effects on cells growth. Treatment of common carp with the recombinant vaccine candidate stimulated high serum or skin mucus specific antibody titers and induced a higher lysozyme, ACP, SOD activity, while fish fed with Lc-pPG or PBS had no detectable immobilizing immune responses. Expression of IL-10, IL-β, IFN-γ, TNF-α genes in the group immunized with recombinant L.casei were significantly (P casei strains were directly delivered and survive throughout the intestinal tract, the recombinant OmpAI was also detected in intestine mucosal. The results showed that common carp received Lc-pPG1-OmpAI (66.7%) and Lc-pPG2-OmpAI (50.0%) had higher survival rates compared with the controls after challenge with A.veronii, indicating that Lc-pPG1-OmpAI and Lc-pPG2-OmpAI had beneficial effects on immune response and enhanced disease resistance of common carp against A.veronii infection. Our study here demonstrates, for the first time, the ability of recombinant L.casei as oral vaccine against A.veronii infection in carps. The combination of OmpAI delivery and LAB

  20. Structural Studies of the Lipopolysaccharide from the Fish Pathogen Aeromonas veronii Strain Bs19, Serotype O16

    Directory of Open Access Journals (Sweden)

    Anna Turska-Szewczuk

    2014-03-01

    Full Text Available Chemical analyses, mass spectrometry, and NMR spectroscopy were applied to study the structure of the lipopolysaccharide (LPS isolated from Aeromonas veronii strain Bs19, serotype O16. ESI-MS revealed that the most abundant LPS glycoforms have tetra-acylated or hexa-acylated lipid A species, consisting of a bisphosphorylated GlcN disaccharide with an AraN residue as a non-stoichiometric substituent, and a core oligosaccharide composed of Hep5Hex3HexN1Kdo1P1. Sugar and methylation analysis together with 1D and 2D 1H and 13C NMR spectroscopy were the main methods used, and revealed that the O-specific polysaccharide (OPS of A. veronii Bs19 was built up of tetrasaccharide repeating units with the structure: →4-α-d-Quip3NAc-(1→3-α-l-Rhap-(1→4-β-d-Galp-(1→3-α-d-GalpNAc-(1→. This composition was confirmed by mass spectrometry. The charge-deconvoluted ESI FT-ICR MS recorded for the LPS preparations identified mass peaks of SR- and R-form LPS species, that differed by Δm = 698.27 u, a value corresponding to the calculated molecular mass of one OPS repeating unit (6dHexNAc6dHexHexHexNAc-H2O. Moreover, unspecific fragmentation spectra confirmed the sequence of the sugar residues in the OPS and allowed to assume that the elucidated structure also represented the biological repeating unit.

  1. Genetic selection of peptide aptamers that interact and inhibit both Small protein B and alternative ribosome-rescue factor A of Aeromonas veronii C4

    Directory of Open Access Journals (Sweden)

    Peng Liu

    2016-08-01

    Full Text Available Aeromonas veronii is a pathogenic gram-negative bacterium, which infects a variety of animals and results in mass mortality. The stalled-ribosome rescues are reported to ensure viability and virulence under stress conditions, of which primarily include trans-translation and alternative ribosome-rescue factor A (ArfA in A. veronii. For identification of specific peptides that interact and inhibit the stalled-ribosome rescues, peptide aptamer library (pTRG-SN-peptides was constructed using pTRG as vector and Staphylococcus aureus nuclease (SN as scaffold protein, in which 16 random amino acids were introduced to form an exposed surface loop. In the meantime both Small Protein B (SmpB which acts as one of the key components in trans-translation, and alternative ribosome-rescue factor A (ArfA were inserted to pBT to constitute pBT-SmpB and pBT-ArfA, respectively. The peptide aptamer PA-2 was selected from pTRG-SN-peptides by bacterial two-hybrid system (B2H employing pBT-SmpB or pBT-ArfA as baits. The conserved sites G133K134 and D138K139R140 of C-terminal SmpB were identified by interacting with N-terminal SN, and concurrently the residue K62 of ArfA was recognized by interacting with the surface loop of the specific peptide aptamer PA-2. The expression plasmids pN-SN or pN-PA-2, which combined the duplication origin of pRE112 with the neokanamycin promoter expressing SN or PA-2, were created and transformed into A. veronii C4, separately. The engineered A. veronii C4 which endowing SN or PA-2 expression impaired growth capabilities under stress conditions including temperatures, sucrose, glucose, potassium chloride (KCl and antibiotics, and the stress-related genes rpoS and nhaP were down-regulated significantly by Quantitative Real-time PCR (qRT-PCR when treating in 2.0% KCl. Thus,the engineered A. veronii C4 conferring PA-2 expression might be potentially attenuated vaccine, and also the peptide aptamer PA-2 could develop as anti

  2. Aeromonas enteropelogenes and Aeromonas ichthiosmia are identical to Aeromonas trota and Aeromonas veronii, respectively, as revealed by small-subunit rRNA sequence analysis.

    Science.gov (United States)

    Collins, M D; Martinez-Murcia, A J; Cai, J

    1993-10-01

    The 16S rRNA gene sequences of the type strains of Aeromonas enteropelogenes and Aeromonas ichthiosmia were determined by polymerase chain reaction direct sequencing in order to clarify their interrelationships with other aeromonad species. On the basis of 16S rRNA gene sequence analysis, A. enteropelogenes and A. ichthiosmia were found to be identical to Aeromonas trota and Aeromonas veronii, respectively.

  3. Characterization and virulence potential of phenotypically diverse Aeromonas veronii isolates recovered from moribund freshwater ornamental fishes of Kerala, India.

    Science.gov (United States)

    Sreedharan, Krishnan; Philip, Rosamma; Singh, Isaac Sarojani Bright

    2013-01-01

    In the present study, we investigated the involvement of Aeromonas spp. in eliciting disease outbreaks in freshwater ornamental fishes across the state of Kerala, India. We investigated three incidences of disease, in which the moribund fishes exhibited clinical signs such as haemorrhagic septicemia (in gouramy, Trichogaster sp.), dropsy (in Oscar, Astronotus ocellatus) and tail rot/fin rot (in gold fish, Carassius carassius). Pure cultures (n = 20 from each fish; 60 in total) of Aeromonas spp. were recovered from the abdominal fluid as well as from internal organs of affected fishes, although they could not be identified to species level because of the variations in their phenotypic characters. The molecular fingerprinting of the isolates using Enterobacterial Repetitive Intergenic Consensus PCR proved the genetic diversity of the isolates from the three sites. The phylogenetic trees constructed using concatenated sequences (using 16S rRNA, gyrA, gyrB and rpoD genes) indicated that they were related to Aeromonas veronii. They exhibited marked cytotoxic and haemolytic activity, which were responsible for the pathogenic potential of the isolates. The isolates possessed multiple virulence genes such as enterotoxins (act and alt), haemolytic toxins (aerA and hlyA), genes involved in type III secretion system (ascV, aexT and ascF-ascG), glycerophospholipid-cholesterol acyltransferase (gcat) and a type IV pilus (tapA) gene, as determined by PCR. Virulence of representative isolates to goldfish was also tested, and we found LD(50) values of 10(4.07)-10(5.35) cfu/fish. Furthermore, the organisms could be recovered as pure cultures from the lesions as well as from the internal organs.

  4. Improvement of methyl orange dye biotreatment by a novel isolated strain, Aeromonas veronii GRI, by SPB1 biosurfactant addition.

    Science.gov (United States)

    Mnif, Inès; Maktouf, Sameh; Fendri, Raouia; Kriaa, Mouna; Ellouze, Semia; Ghribi, Dhouha

    2016-01-01

    Aeromonas veronii GRI (KF964486), isolated from acclimated textile effluent after selective enrichment on azo dye, was assessed for methyl orange biodegradation potency. Results suggested the potential of this bacterium for use in effective treatment of azo-dye-contaminated wastewaters under static conditions at neutral and alkaline pH value, characteristic of typical textile effluents. The strain could tolerate higher doses of dyes as it was able to decolorize up to 1000 mg/l. When used as microbial surfactant to enhance methyl orange biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized slightly the decolorization efficiency at an optimal concentration of about 0.025%. In order to enhance the process efficiency, a Taguchi design was conducted. Phytotoxicity bioassay using sesame and radish seeds were carried out to assess the biotreatment effectiveness. The bacterium was able to effectively decolorize the azo dye when inoculated with an initial optical density of about 0.5 with 0.25% sucrose, 0.125% yeast extract, 0.01% SPB1 biosurfactant, and when conducting an agitation phase of about 24 h after static incubation. Germination potency showed an increase toward the nonoptimized conditions indicating an improvement of the biotreatment. When comparing with synthetic surfactants, a drastic decrease and an inhibition of orange methyl decolorization were observed in the presence of CTAB and SDS. The nonionic surfactant Tween 80 had a positive effect on methyl orange biodecolorization. Also, studies ensured that methyl orange removal by this strain could be due to endocellular enzymatic activities. To conclude, the addition of SPB1 bioemulsifier reduced energy costs by reducing effective decolorization period, biosurfactant stimulated bacterial decolorization method may provide highly efficient, inexpensive, and time-saving procedure in treatment of textile effluents.

  5. Pseudomonas aeruginosa in Healthcare Settings

    Science.gov (United States)

    ... Sepsis Sharps Safety - CDC Transplant Safety Vaccine Safety Pseudomonas aeruginosa in Healthcare Settings Recommend on Facebook Tweet Share ... aeruginosa . Pseudomonas aeruginosa What types of infections does Pseudomonas aeruginosa cause? Serious Pseudomonas infections usually occur in people ...

  6. Benzyl 2-((E-Tosyliminomethylphenylcarbamate

    Directory of Open Access Journals (Sweden)

    Kwang Min Ko

    2016-10-01

    Full Text Available Benzyl 2-((E-tosyliminomethylpenylcarbamate was prepared in good yield and characterized by the condensation reaction of benzyl 2-formylphenylcarbamate with p-toluenesulfonyl amine. The structure of the newly synthesized compound was determined using 1H, 13C-NMR, IR and mass spectral data.

  7. Mu2e Magnetic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Buehler, Marc [Fermilab; Tartaglia, Michael [Fermilab; Tompkins, John [Fermilab; Orozco, Charles [Illinois U., Urbana (main)

    2014-07-01

    The Mu2e experiment at Fermilab is designed to explore charged lepton flavor violation by searching for muon-to-electron conversion. The magnetic field generated by a system of solenoids is crucial for Mu2e and requires accurate characterization to detect any flaws and to produce a detailed field map. Stringent physics goals are driving magnetic field specifications for the Mu2e solenoids. A field mapper is being designed, which will produce detailed magnetic field maps. The uniform field region of the spectrometer volume requires the highest level of precision (1 Gauss per 1 Tesla). During commissioning, multiple magnetic field maps will be generated to verify proper alignment of all magnet coils, and to create the final magnetic field map. In order to design and build a precise field mapping system consisting of Hall and NRM probes, tolerances and precision for such a system need to be evaluated. In this paper we present a design for the Mu2e field mapping hardware, and discuss results from OPERA-3D simulations to specify parameters for Hall and NMR probes. We also present a fitting procedure for the analytical treatment of our expected magnetic measurements.

  8. Improving extracellular production of Serratia marcescens lytic polysaccharide monooxygenase CBP21 and Aeromonas veronii B565 chitinase Chi92 in Escherichia coli and their synergism.

    Science.gov (United States)

    Yang, Yalin; Li, Juan; Liu, Xuewei; Pan, Xingliang; Hou, Junxiu; Ran, Chao; Zhou, Zhigang

    2017-09-07

    Lytic polysaccharide monooxygenases (LPMOs) can oxidize recalcitrant polysaccharides and boost the conversion of the second most abundant polysaccharide chitin by chitinase. In this study, we aimed to achieve the efficient extracellular production of Serratia marcescens LPMO CBP21 and Aeromonas veronii B565 chitinase Chi92 by Escherichia coli. Twelve signal peptides reported with high secretion efficiency were screened to assess the extracellular production efficiency of CBP21 and Chi92, with glycine used as a medium supplement. The results showed that PelB was the most productive signal peptide for the extracellular production of CBP21 and Chi92 in E. coli. Furthermore, CBP21 facilitated the degradation of the three chitin substrates (colloidal chitin, β-chitin, and α-chitin) by Chi92. This study will be valuable for the industrial production and application of the two enzymes for chitin degradation.

  9. Monocyte Profiles in Critically Ill Patients With Pseudomonas Aeruginosa Sepsis

    Science.gov (United States)

    2017-02-02

    Pseudomonas Infections; Pseudomonas Septicemia; Pseudomonas; Pneumonia; Pseudomonal Bacteraemia; Pseudomonas Urinary Tract Infection; Pseudomonas Gastrointestinal Tract Infection; Sepsis; Sepsis, Severe; Critically Ill

  10. Inducción de IgA e IgG anti-omp48 en conejos inmunizados intragástricamente con una fracción extracelular de Aeromonas veronii

    Directory of Open Access Journals (Sweden)

    Eduardo Ruiz-Bustos

    2011-01-01

    Full Text Available Una proteína de membrana externa de 48 kDa (omp48 de Aeromonas veronii (A. veronii, que tiene afinidad por secreciones de la mucosa (tal como mucina, lactoferrina, inmunoglobulinas o colágeno, induce una respuesta inmune estadísticamente significativa al ser administrada intragástricamente a conejos blancos de Nueva Zelanda. Estudios posteriores mostraron una correlación positiva entre las inmunoglobulinas y la respuesta de células productoras de anticuerpo (CPA. La administración intragástrica del antígeno induce una respuesta vigorosa, tanto local como sistémica, principalmente de inmunoglobulinas A y G contra la omp48 de A. veronii. Estas se evidenciaron por la presencia de (i células productoras de anticuerpos contra omp48 en el tracto gastrointestinal, bazo y sangre, y (ii elevados niveles de anticuerpos circulantes.La estimulación del sistema inmune de mucosa mediante antígenos bacterianos inmunogénicos, puede ser una importante alternativa para el control y prevención de enfermedades asociadas a Aeromonas.

  11. Pseudomonas Lipopeptide Biosurfactants

    DEFF Research Database (Denmark)

    Bonnichsen, Lise

    Pseudomonas lipopetide biosurfactants are amphiphilic molecules with a broad range of natural functions. Due to their surface active properties, it has been suggested that Pseudomonas lipopetides potentially play a role in biodegradation of hydrophobic compounds and have essential functions...... in biofilm formation, however, detailed studies of these roles have not yet been carried out. The overall aim of this PhD project was therefore to elucidate in more depth the roles played by Pseudomonas lipopetides in pollutant biodegradation and biofilm formation. This study investigated the effect...... of the Pseudomonas lipopeptides belonging to different structural groups on important biodegradation parameters, mainly; solubilization and emulsification of hydrophobic pollutants (alkanes and PAHs) and increase of cell surface hydrophobicity of bacterial degraders. Ultimately, it was tested if these parameters led...

  12. Population Structure of Pseudomonas aeruginosa

    National Research Council Canada - National Science Library

    Lutz Wiehlmann; Gerd Wagner; Nina Cramer; Benny Siebert; Peter Gudowius; Gracia Morales; Thilo Köhler; Christian van Delden; Christian Weinel; Peter Slickers; Burkhard Tümmler

    2007-01-01

    The metabolically versatile Gram-negative bacterium Pseudomonas aeruginosa inhabits terrestrial, aquatic, animal-, human-, and plant-host-associated environments and is an important causative agent...

  13. Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Alhede, Maria; Bjarnsholt, Thomas; Givskov, Michael

    2014-01-01

    The opportunistic gram-negative bacterium Pseudomonas aeruginosa is implicated in many chronic infections and is readily isolated from chronic wounds, medical devices, and the lungs of cystic fibrosis patients. P. aeruginosa is believed to persist in the host organism due to its capacity to form...... biofilms, which protect the aggregated, biopolymer-embedded bacteria from the detrimental actions of antibiotic treatments and host immunity. A key component in the protection against innate immunity is rhamnolipid, which is a quorum sensing (QS)-regulated virulence factor. QS is a cell-to-cell signaling...

  14. Mu2e Conceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Abrams, R. J.

    2012-03-01

    Mu2e at Fermilab will search for charged lepton flavor violation via the coherent conversion process μ- N → e- N with a sensitivity approximately four orders of magnitude better than the current world's best limits for this process. The experiment's sensitivity offers discovery potential over a wide array of new physics models and probes mass scales well beyond the reach of the LHC. We describe herein the conceptual design of the proposed Mu2e experiment. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-1 approval, which was granted July 11, 2012.

  15. Mu2e Conceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Ray, R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Glenzinski, D. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2012-03-01

    Mu2e at Fermilab will search for charged lepton flavor violation via the coherent conversion process mu- N → e- N with a sensitivity approximately four orders of magnitude better than the current world's best limits for this process. The experiment's sensitivity offers discovery potential over a wide array of new physics models and probes mass scales well beyond the reach of the LHC. We describe herein the conceptual design of the proposed Mu2e experiment. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-1 approval, which was granted July 11, 2012.

  16. Mu2e Technical Design Report

    CERN Document Server

    Bartoszek, L; Miller, J P; Mott, J; Palladino, A; Quirk, J; Roberts, B L; Crnkovic, J; Polychronakos, V; Tishchenko, V; Yamin, P; Cheng, C -h; Echenard, B; Flood, K; Hitlin, D G; Kim, J H; Miyashita, T S; Porter, F C; Röhrken, M; Trevor, J; Zhu, R -Y; Heckmaier, E; Kang, T I; Lim, G; Molzon, W; You, Z; Artikov, A M; Budagov, J A; Davydov, Yu I; Glagolev, V V; Simonenko, A V; Usubov, Z U; Oh, S H; Wang, C; Ambrosio, G; Andreev, N; Arnold, D; Ball, M; Bernstein, R H; Bianchi, A; Biery, K; Bossert, R; Bowden, M; Brandt, J; Brown, G; Brown, H; Buehler, M; Campbell, M; Cheban, S; Chen, M; Coghill, J; Coleman, R; Crowley, C; Deshpande, A; Deuerling, G; Dey, J; Dhanaraj, N; Dinnon, M; Dixon, S; Drendel, B; Eddy, N; Evans, R; Evbota, D; Fagan, J; Feher, S; Fellenz, B; Friedsam, H; Gallo, G; Gaponenko, A; Gardner, M; Gaugel, S; Genser, K; Ginther, G; Glass, H; Glenzinski, D; Hahn, D; Hansen, S; Hartsell, B; Hays, S; Hocker, J A; Huedem, E; Huffman, D; Ibrahim, A; Johnstone, C; Kashikhin, V; Kashikhin, V V; Kasper, P; Kiper, T; Knapp, D; Knoepfel, K; Kokoska, L; Kozlovsky, M; Krafczyk, G; Kramp, M; Krave, S; Krempetz, K; Kutschke, R K; Kwarciany, R; Lackowski, T; Lamm, M J; Larwill, M; Leavell, F; Leeb, D; Leveling, A; Lincoln, D; Logashenko, V; Lombardo, V; Lopes, M L; Makulski, A; Martinez, A; McArthur, D; McConologue, F; Michelotti, L; Mokhov, N; Morgan, J; Mukherjee, A; Murat, P; Nagaslaev, V; Neuffer, D V; Nicol, T; Niehoff, J; Nogiec, J; Olson, M; Orris, D; Ostojic, R; Page, T; Park, C; Peterson, T; Pilipenko, R; Pla-Dalmau, A; Poloubotko, V; Popovic, M; Prebys, E; Prieto, P; Pronskikh, V; Pushka, D; Rabehl, R; Ray, R E; Rechenmacher, R; Rivera, R; Robotham, W; Rubinov, P; Rusu, V L; Scarpine, V; Schappert, W; Schoo, D; Stefanik, A; Still, D; Tang, Z; Tanovic, N; Tartaglia, M; Tassotto, G; Tinsley, D; Tschirhart, R S; Vogel, G; Wagner, R; Wands, R; Wang, M; Werkema, S; White, H B; Whitmore, J; Wielgos, R; Woods, R; Worel, C; Zifko, R; Ciambrone, P; Colao, F; Cordelli, M; Corradi, G; Dane, E; Giovannella, S; Happacher, F; Luca, A; Miscetti, S; Ponzio, B; Pileggi, G; Saputi, A; Sarra, I; Soleti, R S; Stomaci, V; Martini, M; Fabbricatore, P; Farinon, S; Musenich, R; Alexander, D; Daniel, A; Empl, A; Hungerford, E V; Lau, K; Gollin, G D; Huang, C; Roderick, D; Trundy, B; Brown, D Na; Ding, D; Kolomensky, Yu G; Lee, M J; Cascella, M; Grancagnolo, F; Ignatov, F; Innocente, A; L'Erario, A; Miccoli, A; Maffezzoli, A; Mazzotta, P; Onorato, G; Piacentino, G M; Rella, S; Rossetti, F; Spedicato, M; Tassielli, G; Taurino, A; Zavarise, G; Hooper, R; Brown, D No; Djilkibaev, R; Matushko, V; Ankenbrandt, C; Boi, S; Dychkant, A; Hedin, D; Hodge, Z; Khalatian, V; Majewski, R; Martin, L; Okafor, U; Pohlman, N; Riddel, R S; Shellito, A; de Gouvea, A L; Cervelli, F; Carosi, R; Di Falco, S; Donati, S; Lomtadze, T; Pezzullo, G; Ristori, L; Spinella, F; Jones, M; Corcoran, M D; Orduna, J; Rivera, D; Bennett, R; Caretta, O; Davenne, T; Densham, C; Loveridge, P; Odell, J; Bomgardner, R; Dukes, E C; Ehrlich, R; Frank, M; Goadhouse, S; Ho, E; Ma, H; Oksuzian, Y; Purvis, J; Wu, Y; Hertzog, D W; Kammel, P; Lynch, K R; Popp, J L

    2015-01-01

    The Mu2e experiment at Fermilab will search for charged lepton flavor violation via the coherent conversion process mu- N --> e- N with a sensitivity approximately four orders of magnitude better than the current world's best limits for this process. The experiment's sensitivity offers discovery potential over a wide array of new physics models and probes mass scales well beyond the reach of the LHC. We describe herein the preliminary design of the proposed Mu2e experiment. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-2 approval.

  17. Mu2e Technical Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Bartoszek, L.; et al.

    2014-10-01

    Fermi National Accelerator Laboratory and the Mu2e Collaboration, composed of about 155 scientists and engineers from 28 universities and laboratories around the world, have collaborated to create this technical design for a new facility to study charged lepton flavor violation using the existing Department of Energy investment in the Fermilab accelerator complex. Mu2e proposes to measure the ratio of the rate of the neutrinoless, coherent conversion of muons into electrons in the field of a nucleus, relative to the rate of ordinary muon capture on the nucleus. The conversion process is an example of charged lepton flavor violation (CLFV), a process that has never been observed experimentally. The significant motivation behind the search for muon-to-electron conversion is discussed in Chapter 3.

  18. [Meningoencephalitis caused by Pseudomonas cepacia].

    Science.gov (United States)

    Pérez Monrás, Miriam Fina; Batlle Almodóvar, María del Carmen; González, Cernero; Tamargo Martínez, Isis; Meneses, Félix Dickinson

    2006-01-01

    A case of meningoencephalitis of bacterial etiology caused by Pseudomonas cepacia was described. The strain was received at the Reference Laboratory of Bacterial Acute Respiratory Infections of "Pedro Kouri" Institute of Tropical Medicine, where its microbiological identification was confirmed. This isolation was a finding in an adult immunocompetent patient. The evolution was favourable with no sequelae for his future life. Pseudomona cepacia has been associated with respiratory infections in patients with cystic fibrosis. Patients with Pseudomonas cepacia may be asymptomatic or present fatal acute and fulminant infection.

  19. Pseudomonas aeruginosa biofilm infections

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim

    2014-01-01

    Bacteria in natural, industrial and clinical settings predominantly live in biofilms, i.e., sessile structured microbial communities encased in self-produced extracellular matrix material. One of the most important characteristics of microbial biofilms is that the resident bacteria display...... a remarkable increased tolerance toward antimicrobial attack. Biofilms formed by opportunistic pathogenic bacteria are involved in devastating persistent medical device-associated infections, and chronic infections in individuals who are immune-compromised or otherwise impaired in the host defense. Because...... the use of conventional antimicrobial compounds in many cases cannot eradicate biofilms, there is an urgent need to develop alternative measures to combat biofilm infections. The present review is focussed on the important opportunistic pathogen and biofilm model organism Pseudomonas aeruginosa. Initially...

  20. Pseudomonas folliculitis in Arabian baths.

    Science.gov (United States)

    Molina-Leyva, Alejandro; Ruiz-Ruigomez, Maria

    2013-07-14

    A 35-year-old man presented with a painful cutaneous skin eruption that was localized on the upper trunk. He stated that the previous weekend he had attended an Arabian bath. The physical examination revealed multiple hair follicle-centered papulopustules surrounded by an erythematous halo. A clinical diagnosis of pseudomonas folliculitis was made and treatment was prescribed. Afterwards Pseudomonas aeruginosa was isolated from a pustule culture. Pseudomonas folliculitis is a bacterial infection of the hair follicles. The most common reservoirs include facilities with hot water and complex piping systems that are difficult to clean, such as hot tubs and bathtubs. Despite adequate or high chlorine levels, Pseudomonas aeruginosa can grow within a biofilm.

  1. Final screening assessment for Pseudomonas putida ATCC 12633, Pseudomonas putida ATCC 31483, Pseudomonas putida ATCC 31800, Pseudomonas putida ATCC 700369

    National Research Council Canada - National Science Library

    2017-01-01

    "Pursuant to paragraph 74(b) of the Canadian Environmental Protection Act, 1999 (CEPA), the Minister of the Environment and the Minister of Health have conducted a screening assessment on four strains of Pseudomonas putida...

  2. Chronic Pseudomonas aeruginosa cervical osteomyelitis

    Directory of Open Access Journals (Sweden)

    Sujeet Kumar Meher

    2016-01-01

    Full Text Available Pseudomonas aeruginosa is a rare cause of osteomyelitis of the cervical spine and is usually seen in the background of intravenous drug use and immunocompromised state. Very few cases of osteomyelitis of the cervical spine caused by pseudomonas aeruginosa have been reported in otherwise healthy patients. This is a case presentation of a young female, who in the absence of known risk factors for cervical osteomyelitis presented with progressively worsening neurological signs and symptoms.

  3. Silver against Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Kirketerp-Møller, K.; Kristiansen, S.

    2007-01-01

    bacteria in both the planktonic and biofilm modes of growth. The action of silver on mature in vitro biofilms of Pseudomonas aeruginosa, a primary pathogen of chronic infected wounds, was investigated. The results show that silver is very effective against mature biofilms of P. aeruginosa...

  4. Functional characterization and application of a tightly regulated MekR/P mekA expression system in Escherichia coli and Pseudomonas putida.

    Science.gov (United States)

    Graf, Nadja; Altenbuchner, Josef

    2013-09-01

    A methyl ethyl ketone (MEK)-inducible system based on the broad-host-range plasmid pBBR1MCS2 and on the P mekA promoter region of the MEK degradation operon of Pseudomonas veronii MEK700 was characterized in Escherichia coli JM109 and Pseudomonas putida KT2440. For validation, β-galactosidase (lacZ) was used as a reporter. The novel system, which is positively regulated by MekR, a member of the AraC/XylS family of regulators, was shown to be subject to carbon catabolite repression by glucose, which, however, could not be attributed to the single action of the global regulators Crc and PtsN. An advantage is its extremely tight regulation accompanied with three magnitudes of fold increase of gene expression after treatment with MEK. The transcriptional start site of P mekA was identified by primer extension, thereby revealing a potential stem-loop structure at the 5' end of the mRNA. Since MekR was highly insoluble, its putative binding site was identified through sequence analysis. The operator seems to be composed of a 15-bp tandem repeat (CACCN5CTTCAA) separated by a 6-bp spacer region, which resembles known binding patterns of other members of the AraC/XylS family. Subsequent mutational modifications of the putative operator region confirmed its importance for transcriptional activation. As the -35 promoter element seems to be overlapped by the putative operator, a class II activation mechanism is assumed.

  5. Phylogenomics and systematics in Pseudomonas

    Directory of Open Access Journals (Sweden)

    Margarita eGomila

    2015-03-01

    Full Text Available The genus Pseudomonas currently contains 144 species, making it the genus of Gram-negative bacteria that contains the largest number of species. Currently, multilocus sequence analysis (MLSA is the preferred method for establishing the phylogeny between species and genera. Four partial gene sequences of housekeeping genes (16S rRNA, gyrB, rpoB and rpoD were obtained from 112 complete or draft genomes of strains related to the genus Pseudomonas that were available in databases. These genes were analyzed together with the corresponding sequences of 133 Pseudomonas type strains of validly published species to assess their correct phylogenetic assignations. We confirmed that 30% of the sequenced genomes of non-type strains were not correctly assigned at the species level in the accepted taxonomy of the genus and that 20% of the strains were not identified at the species level. Most of these strains had been isolated and classified several years ago, and their taxonomic status has not been updated by modern techniques. MLSA was also compared with indices based on the analysis of whole-genome sequences that have been proposed for species delineation, such as tetranucleotide usage patterns (TETRA, average nucleotide identity (ANIm, based on MUMmer and ANIb, based on BLAST and genome-to-genome distance (GGDC. TETRA was useful for discriminating Pseudomonas from other genera, whereas ANIb and GGDC clearly separated strains of different species. ANIb showed the strongest correlation with MLSA. The correct species classification is a prerequisite for most diversity and evolutionary studies. This work highlights the necessity for complete genomic sequences of type strains to build a phylogenomic taxonomy and that all new genome sequences submitted to databases should be correctly assigned to species to avoid taxonomic inconsistencies.

  6. Pseudomonas-follikulitis efter badning i spabad

    DEFF Research Database (Denmark)

    Uldall Pallesen, Kristine Appel; Andersen, Klaus Ejner; Mørtz, Charlotte Gotthard

    2012-01-01

    Pseudomonas aeruginosa is a rare cause of folliculitis. Pseudomonas folliculitis can develop after contact with contaminated water from swimming pools, hot tubs and spa baths. Systemic therapy may be indicated in patients with widespread lesions, systemic symptoms or in immunosuppressed patients....... We describe a 23-year-old healthy woman who developed a pustular rash and general malaise after using a spa bath contaminated with Pseudomonas aeruginosa. Bacterial culture from a pustule confirmed Pseudomonas folliculitis and the patient was treated with ciprofloxacin with rapid good effect....

  7. Analysis list: Gtf2e2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Gtf2e2 Blood,Liver + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Gtf2...e2.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Gtf2e2.5.tsv http://dbarchive.biosciencedbc.j...p/kyushu-u/mm9/target/Gtf2e2.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Gtf2e2.Blood.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Gtf2e2.Liver.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Blood.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Liver.gml ...

  8. Petroleum-hydrocarbons biodegradation by Pseudomonas strains ...

    African Journals Online (AJOL)

    Many indigenous microorganisms in water and soil are capable of degrading hydrocarbon contaminants. In this study, two bacterial strains were isolated from a contaminated soil of a refinery of Arzew (Oran). The isolated strains were identified as Pseudomonas aeruginosa (P3) and Pseudomonas fluoresens (P4).

  9. Optimization of alkaline protease production from Pseudomonas ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-15

    Dec 15, 2009 ... A protease producing bacteria was isolated from meat waste contaminated soil and identified as. Pseudomonas ... Key words: Alkaline protease, casein agar, meat waste contaminated soil, Pseudomonas fluorescens. INTRODUCTION ... advent of new frontiers in biotechnology, the spectrum of protease ...

  10. A2E, a byproduct of the visual cycle.

    Science.gov (United States)

    Sparrow, Janet R; Fishkin, Nathan; Zhou, Jilin; Cai, Bolin; Jang, Young P; Krane, Sonja; Itagaki, Yasuhiro; Nakanishi, Koji

    2003-12-01

    A substantial portion of the lipofuscin that accumulates with age and in some retinal disorders in retinal pigment epithelial (RPE) cells, forms as a consequence of light-related vitamin A recycling. Major constituents of RPE lipofuscin are the di-retinal conjugate A2E and its photoisomers. That the accretion of A2E has consequences for the cell, with the adverse effects of A2E being attributable to its amphiphilic structure and its photoreactivity, is consistent with evidence of an association between atrophic age-related macular degeneration (AMD) and excessive lipofuscin accumulation.

  11. [Pseudomonas genus bacteria on weeds].

    Science.gov (United States)

    Gvozdiak, R I; Iakovleva, L M; Pasichnik, L A; Shcherbina, T N; Ogorodnik, L E

    2005-01-01

    It has been shown in the work that the weeds (couch-grass and ryegrass) may be affected by bacterial diseases in natural conditions, Pseudomonas genus bacteria being their agents. The isolated bacteria are highly-aggressive in respect of the host-plant and a wide range of cultivated plants: wheat, rye, oats, barley, apple-tree and pear-tree. In contrast to highly aggressive bacteria isolated from the affected weeds, bacteria-epi phytes isolated from formally healthy plants (common amaranth, orache, flat-leaved spurge, field sow thistle, matricary, common coltsfoot, narrow-leaved vetch) and identified as P. syringae pv. coronafaciens, were characterized by weak aggression. A wide range of ecological niches of bacteria evidently promote their revival and distribution everywhere in nature.

  12. CYP2E1 hydroxylation of aniline involves negative cooperativity.

    Science.gov (United States)

    Hartman, Jessica H; Knott, Katie; Miller, Grover P

    2014-02-01

    CYP2E1 plays a role in the metabolic activation and elimination of aniline, yet there are conflicting reports on its mechanism of action, and hence relevance, in aniline metabolism. Based on our work with similar compounds, we hypothesized that aniline binds two CYP2E1 sites during metabolism resulting in cooperative reaction kinetics and tested this hypothesis through rigorous in vitro studies. The kinetic profile for recombinant CYP2E1 demonstrated significant negative cooperativity based on a fit of data to the Hill equation (n=0.56). Mechanistically, the data were best explained through a two-binding site cooperative model in which aniline binds with high affinity (K(s)=30 μM) followed by a second weaker binding event (K(ss)=1100 uM) resulting in a threefold increase in the oxidation rate. Binding sites for aniline were confirmed by inhibition studies with 4-methylpyrazole. Inhibitor phenotyping experiments with human liver microsomes validated the central role for CYP2E1 in aniline hydroxylation and indicated minor roles for CYP2A6 and CYP2C9. Importantly, inhibition of minor metabolic pathways resulted in a kinetic profile for microsomal CYP2E1 that replicated the preferred mechanism and parameters observed with the recombinant enzyme. Scaled modeling of in vitro CYP2E1 metabolism of aniline to in vivo clearance, especially at low aniline levels, led to significant deviations from the traditional model based on non-cooperative, Michaelis-Menten kinetics. These findings provide a critical mechanistic perspective on the potential importance of CYP2E1 in the metabolic activation and elimination of aniline as well as the first experimental evidence of a negatively cooperative metabolic reaction catalyzed by CYP2E1. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Multilocus sequence typing of carbapenem resistant Pseudomonas ...

    African Journals Online (AJOL)

    Background: Pseudomonas aeruginosa is an important nosocomial pathogen that exhibits multiple drug resistance with increasing frequency, especially to carbapenems making patient treatment difficult. Carbapenem-resistance may be caused by porin gene mutations, active drug efflux, and carbapenemase production.

  14. Dynamics of Pseudomonas aeruginosa Genome Evolution

    National Research Council Canada - National Science Library

    Kalai Mathee; Giri Narasimhan; Camilo Valdes; Xiaoyun Qiu; Jody M. Matewish; Michael Koehrsen; Antonis Rokas; Chandri N. Yandava; Reinhard Engels; Erliang Zeng; Raquel Olavarietta; Melissa Doud; Roger S. Smith; Philip Montgomery; Jared R. White; Paul A. Godfrey; Chinnappa Kodira; Bruce Birren; James E. Galagan; Stephen Lory

    2008-01-01

    One of the hallmarks of the Gram-negative bacterium Pseudomonas aeruginosa is its ability to thrive in diverse environments that includes humans with a variety of debilitating diseases or immune deficiencies...

  15. Pseudomonas aeruginosa: resistance to the max

    National Research Council Canada - National Science Library

    Poole, Keith

    2011-01-01

    Pseudomonas aeruginosa is intrinsically resistant to a variety of antimicrobials and can develop resistance during anti-pseudomonal chemotherapy both of which compromise treatment of infections caused by this organism...

  16. Antibiotic Conditioned Growth Medium of Pseudomonas Aeruginosa

    Science.gov (United States)

    Benathen, Isaiah A.; Cazeau, Barbara; Joseph, Njeri

    2004-01-01

    A simple method to study the consequences of bacterial antibiosis after interspecific competition between microorganisms is presented. Common microorganisms are used as the test organisms and Pseudomonas aeruginosa are used as the source of the inhibitor agents.

  17. Pseudomonas aeruginosa (Family Pseudomonadaceae) is an ...

    African Journals Online (AJOL)

    Pseudomonas aeruginosa (Family Pseudomonadaceae) is an obligate aerobic, motile, gram negative bacillus.which is able to grow and survive in almost any environment and resistant to temperature extremes. It is involved in the etiology of several diseases i.

  18. Active Immunization with Lipopolysaccharide Pseudomonas Antigen for Chronic Pseudomonas Bronchopneumonia in Guinea Pigs

    OpenAIRE

    Pennington, James E.; Hickey, William F.; Blackwood, Linda L.; Arnaut, M. Amin

    1981-01-01

    Chronic respiratory infection with Pseudomonas aeruginosa is a leading clinical problem among patients with cystic fibrosis. Because antimicrobial agents are usually ineffective in eradicating these infections, additional therapeutic or prophylactic measures should be considered. In this study, an experimental guinea pig model of chronic Pseudomonas aeruginosa bronchopneumonia was utilized to determine whether active immunization with lipopolysaccharide (LPS) P. aeruginosa antigen may favorab...

  19. M2e-Based Universal Influenza A Vaccines

    Science.gov (United States)

    Deng, Lei; Cho, Ki Joon; Fiers, Walter; Saelens, Xavier

    2015-01-01

    The successful isolation of a human influenza virus in 1933 was soon followed by the first attempts to develop an influenza vaccine. Nowadays, vaccination is still the most effective method to prevent human influenza disease. However, licensed influenza vaccines offer protection against antigenically matching viruses, and the composition of these vaccines needs to be updated nearly every year. Vaccines that target conserved epitopes of influenza viruses would in principle not require such updating and would probably have a considerable positive impact on global human health in case of a pandemic outbreak. The extracellular domain of Matrix 2 (M2e) protein is an evolutionarily conserved region in influenza A viruses and a promising epitope for designing a universal influenza vaccine. Here we review the seminal and recent studies that focused on M2e as a vaccine antigen. We address the mechanism of action and the clinical development of M2e-vaccines. Finally, we try to foresee how M2e-based vaccines could be implemented clinically in the future. PMID:26344949

  20. R2E – identifying problems, mitigating risks

    CERN Multimedia

    Anaïs Schaeffer

    2013-01-01

    During LS1, the R2E project team will be working on a task as painstaking as it is crucial: to achieve a sixfold reduction in the number of electronic malfunctions caused by radiation. On their success depends the ability of the accelerator to function correctly at nominal energy. No mean challenge, considering it comes on top of the tenfold reduction already achieved since 2009.   The graph plots the rate of LHC beam dumps due to single-event effects against beam luminosity. An indication of the challenge that faces the R2E project teams during LS1! The origins of the project known as R2E (Radiation to Electronics) go back to 2007, when the CNGS (CERN Neutrinos to Gran Sasso) experiment was being commissioned. "Right from the outset, some CNGS control systems were causing problems. They would regularly break down in operations with beam," recalls Markus Brugger, head of the R2E project. "Even though the beam intensity was very low, we began to suspect that radiati...

  1. Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

    DEFF Research Database (Denmark)

    Johansen, Helle Krogh; Gøtzsche, Peter C

    2013-01-01

    Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed.......Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed....

  2. Airway epithelial cell tolerance to Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Verghese Margrith W

    2005-04-01

    Full Text Available Abstract Background The respiratory tract epithelium is a critical environmental interface that regulates inflammation. In chronic infectious airway diseases, pathogens may permanently colonize normally sterile luminal environments. Host-pathogen interactions determine the intensity of inflammation and thus, rates of tissue injury. Although many cells become refractory to stimulation by pathogen products, it is unknown whether the airway epithelium becomes either tolerant or hypersensitive in the setting of chronic infection. Our goals were to characterize the response of well-differentiated primary human tracheobronchial epithelial cells to Pseudomonas aeruginosa, to understand whether repeated exposure induced tolerance and, if so, to explore the mechanism(s. Methods The apical surface of well-differentiated primary human tracheobronchial epithelial cell cultures was repetitively challenged with Pseudomonas aeruginosa culture filtrates or the bacterial media control. Toxicity, cytokine production, signal transduction events and specific effects of dominant negative forms of signaling molecules were examined. Additional experiments included using IL-1β and TNFα as challenge agents, and performing comparative studies with a novel airway epithelial cell line. Results An initial challenge of the apical surface of polarized human airway epithelial cells with Pseudomonas aeruginosa culture filtrates induced phosphorylation of IRAK1, JNK, p38, and ERK, caused degradation of IκBα, generation of NF-κB and AP-1 transcription factor activity, and resulted in IL-8 secretion, consistent with activation of the Toll-like receptor signal transduction pathway. These responses were strongly attenuated following a second Pseudomonas aeruginosa, or IL-1β, but not TNFα, challenge. Tolerance was associated with decreased IRAK1 protein content and kinase activity and dominant negative IRAK1 inhibited Pseudomonas aeruginosa -stimulated NF-κB transcriptional

  3. A2e High Fidelity Modeling: Strategic Planning Meetings

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, Steven W. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sprague, Michael A. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Womble, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Barone, Matt [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-11-01

    Atmosphere to electrons (A2e) is a multi-year U.S. Department of Energy (DOE) research initiative targeting significant reductions in the cost of wind energy through an improved understanding of the complex physics governing wind flow into and through whole wind farms. Better insight into the flow physics of large multi-turbine arrays will address the plant-level energy losses, is likely to reduce annual operational costs by hundreds of millions of dollars, and will improve project financing terms to more closely resemble traditional capital projects. In support of this initiative, two planning meetings were convened, bringing together professionals from universities, national laboratories, and industry to discuss wind plant modeling challenges, requirements, best practices, and priorities. This report documents the combined work of the two meetings and serves as a key part of the foundation for the A2e/HFM effort for predictive modeling of whole wind plant physics.

  4. Stability Issues of the Mu2e Proton Beam

    Energy Technology Data Exchange (ETDEWEB)

    Ng, K.Y.; /Fermilab

    2009-05-01

    Stability issues of the mu2e proton beam are discussed. These include space-charge distortion of bunch shape, microwave instabilities, mode-coupling instabilities, head-tail instabilities, as well as electron-cloud effects. We have studied several beam stability issues of the proton beam heading to the target for the mu2e experiment. We find bunch-shape distortions driven by the space charge force is reasonably small, and longitudinal microwave instability will unlikely to occur. Electron-cloud buildup, with density up to {rho}{sub e} {approx} 2 x 10{sup 12} m{sup -3} in the Accumulator, can probably drive head-tail instabilities. However, these, together with the instabilities driven by the resistive-wall impedance can be avoided by restricting the chromaticity to larger than {approx} 0.2. TMCI will not occur even when the electron-cloud wake is included.

  5. The Mu2e Solenoid Cold Mass Position Monitor System

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, T. [Fermilab; Feher, S. [Fermilab; Friedsam, H. W. [Fermilab; Lamm, M. J. [Fermilab; Nicol, T. [Fermilab; Page T., Page T. [Fermilab

    2017-01-01

    The Mu2e experiment at Fermilab is designed to search for charged-lepton flavor violation by looking for muon to electron conversions in the field of the nucleus. The concept of the experiment is to generate a low momentum muon beam, stopping the muons in a target and measuring the momentum of the outgoing electrons. The implementation of this approach utilizes a complex magnetic field composed of graded solenoidal and toroidal fields. The location of the solenoid cold mass relative to external fiducials is needed for alignment as well as monitoring coil movements during cool down and magnet excitation. This paper describes a novel design of a Cold Mass Position Monitor System (CMPS) that will be implemented for the Mu2e experiment.

  6. Diversity of small RNAs expressed in Pseudomonas species

    DEFF Research Database (Denmark)

    Gomez-Lozano, Mara; Marvig, Rasmus Lykke; Molina-Santiago, Carlos

    2015-01-01

    RNA sequencing (RNA-seq) has revealed several hundreds of previously undetected small RNAs (sRNAs) in all bacterial species investigated, including strains of Pseudomonas aeruginosa, Pseudomonas putida and Pseudomonas syringae. Nonetheless, only little is known about the extent of conservation of...

  7. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... genus Pseudomonas. Pseudomonas aeruginosa is a major cause of hospital-acquired infections, and has been..., abscesses, and meningitis (inflammation of brain membranes). Pseudomonas pseudomallei causes melioidosis, a chronic pneumonia. (b) Classification. Class II (special controls). The device is exempt from the...

  8. Growth of Pseudomonas spp. in cottage cheese

    DEFF Research Database (Denmark)

    Østergaard, Nina Bjerre; Dalgaard, Paw

    of spoilage microorganisms in cottage cheese can cause undesirable alterations in flavour, odour, appearance and texture. Contamination and growth of psychrotolerant pseudomonads including Pseudomonas fragi and Pseudomonas putida has been reported for cottage cheese but the influence of these bacteria...... on product spoilage and shelf-life remains poorly described. The present study used a quantitative microbial ecology approach to model and predict the effect of product characteristics and storage conditions on growth of psychrotolerant pseudomonads in cottage cheese. The effect of temperature (5-15˚C) and p...

  9. The Mu2e Undoped CsI Crystal Calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Atanov, N.; et al.

    2018-01-07

    The Mu2e experiment at Fermilab will search for Charged Lepton Flavor Violating conversion of a muon to an electron in an atomic field. The Mu2e detector is composed of a tracker, an electromagnetic calorimeter and an external system, surrounding the solenoid, to veto cosmic rays. The calorimeter plays an important role to provide: a) excellent particle identification capabilities; b) a fast trigger filter; c) an easier tracker track reconstruction. Two disks, located downstream of the tracker, contain 674 pure CsI crystals each. Each crystal is read out by two arrays of UV-extended SiPMs. The choice of the crystals and SiPMs has been finalized after a thorough test campaign. A first small scale prototype consisting of 51 crystals and 102 SiPM arrays has been exposed to an electron beam at the BTF (Beam Test Facility) in Frascati. Although the readout electronics were not the final, results show that the current design is able to meet the timing and energy resolution required by the Mu2e experiment.

  10. Research and Development for the Mu2e Extinction Monitor

    Energy Technology Data Exchange (ETDEWEB)

    Mott, Casey Benjamin [Northern Illinois U.

    2016-01-01

    Mu2e is a planned experiment to search for flavor-violating conversion from a muon to an electron. The experiment will use a pulsed 8 GeV proton beam to produce muons which will then stop in an aluminum target. Mu2e will search for the $\\mu^- + Al \\rightarrow e^- + Al$ process. For Mu2e, an extinction rate of 10$^{-10}$ is required to reduce the backgrounds to an acceptable level. Extinction is the ratio of the amount of protons striking the production target between beam pulses to the number striking it during the beam pulse. One of the backgrounds, off-target interactions, was simulated using G4beamline and Fermilab's Grid setup to confirm that an extinction rate of 10$^{-10}$ is possible. The extinction level will be measured by the extinction monitor which will include scintillation counters read out by photomultiplier tubes. In order to build a beam time profile, low fake responses (after pulses) are needed in the photomultiplier tubes. This thesis determines the best combination of resistors, voltage, and other components that provide the lowest after pulse rate.

  11. Target Station Design for the Mu2e Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Pronskikh, Vitaly [Fermilab; Ambrosio, Giorgio [Fermilab; Campbell, Michael [Fermilab; Coleman, Richard [Fermilab; Ginther, George [Fermilab; Kashikhin, Vadim [Fermilab; Krempetz, Kurt [Fermilab; Lamm, Michael [Fermilab; Lee, Ang [Fermilab; Leveling, Anthony [Fermilab; Mokhov, Nikolai [Fermilab; Nagaslaev, Vladimir [Fermilab; Stefanik, Andrew [Fermilab; Striganov, Sergei [Fermilab; Werkema, Steven [Fermilab; Bartoszek, Larry [Technicare; Densham, Chris [Rutherford; Loveridge, Peter [Rutherford; Lynch, Kevin [BMCC, New York; Popp, James [BMCC, New York

    2014-07-01

    The Mu2e experiment at Fermilab is devoted to search for the conversion of a negative muon into an electron in the field of a nucleus without emission of neutrinos. One of the main parts of the Mu2e experimental setup is its Target Station in which negative pions are generated in interactions of the 8-GeV primary proton beam with a tungsten target. A large-aperture 5-T superconducting production solenoid (PS) enhances pion collection, and an S-shaped transport solenoid (TS) delivers muons and pions to the Mu2e detector. The heat and radiation shield (HRS) protects the PS and the first TS coils. A beam dump absorbs the spent beam. In order for the PS superconducting magnet to operate reliably the sophisticated HRS was designed and optimized for performance and cost. The beam dump was designed to absorb the spent beam and maintaining its temperature and air activation in the hall at the allowable level. Comprehensive MARS15 simulations have been carried out to optimize all the parts while maximizing muon yield. Results of simulations of critical radiation quantities and their implications on the overall Target Station design and integration will be reported.

  12. Plant growth promotion by Pseudomonas fluorescens

    NARCIS (Netherlands)

    Cheng, X.

    2016-01-01

    Pseudomonas fluorescens is a Gram-negative rod shaped bacterium that has a versatile metabolism and is widely spread in soil and water. P. fluorescens strain SBW25 (Pf.SBW25) is a well-known model strain to study bacterial evolution, plant colonization and biocontrol of plant diseases. It produces

  13. Antibiograms of Staphylococcus Aureus and Pseudomonas ...

    African Journals Online (AJOL)

    While there was no bacterial growth after 48hrs incubation recorded for group one, only 5(13.9%) samples yielded growth of Staphylococcus aureus for group two with 31(86.1%) yielding no bacterial growth. All group three samples yielded profuse growth of which 11(36.7%) yielded Pseudomonas aeruginosa and ...

  14. Transesterification of Jatropha oil using immobilized Pseudomonas ...

    African Journals Online (AJOL)

    mild transesterification has become of much current interest for alternative fuel production. In the present study the ability of a commercial immobilized Pseudomonas fluorescens MTCC 103 to catalyze the transesterification of Jatropha oil and methanol was investigated. The cell of P. fluorescens was easily immobilized ...

  15. Behavioral response of resistant and sensitive Pseudomonas ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-18

    Jul 18, 2008 ... Key words: Pseudomonas aeruginosa, cadmium stress, heavy metal resistance. INTRODUCTION. The release of .... plasmids located in the bacterial strains isolated from agricultural and industrial soils ..... esteraromaticum S51 with other strains of non-flocculating sludge bacteria. IWA's Water Environ.

  16. Evaluation of gamma irradiation effect and Pseudomonas ...

    African Journals Online (AJOL)

    Antagonistic effect of Pseudomonas fluorescens and influence of gamma irradiation on the development of Penicillium expansum, the causal agent of postharvest disease on apple fruit was studied. P. fluorescens was originally isolated from rhizosphere of the apple trees. Suspension of P. fluorescens and P. expansum ...

  17. Bacteriocinogenicity and production of pyocins from Pseudomonas ...

    African Journals Online (AJOL)

    The susceptible organisms include Bacillus cereus, Listeria monocytogenes, Klebsiella spp., Staphylococcus aureus, S. epidermidis, Proteus spp. and Vibrio parahaemolyticus. The results of this study have provided evidence for broadspectrum antibacterial activity of pyocins elicited by Pseudomonas species from Nigeria ...

  18. Isolation and characterization of arsenite oxidizing Pseudomonas ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-08

    Mar 8, 2010 ... indicates its potential application in biological treatment of wastewaters contaminated with arsenic. Key words: Arsenic, wastewater, Pseudomonas lubricans, bioremediation. INTRODUCTION. Arsenic is the most prevalent environmental toxic metal and is first on the superfund list of hazardous substances.

  19. Antibiotics Susceptibility Pattern of Pseudomonas aeruginosa ...

    African Journals Online (AJOL)

    ABSTRACT: This work investigated the prevalence and antibiotics sensitivity of Pseudomonas aeruginosa isolated from wounds of patients attending Ahmadu Bello University Teaching Hospital (ABUTH), Zaria-Nigeria. One hundred Isolates were characterized and identified from the specimens using standard ...

  20. Characterization of drug resistant Pseudomonas aeruginosa and ...

    African Journals Online (AJOL)

    Despite the fact that they remain asymptomatic in many cases, they nevertheless play significant roles in the epidemiology of these pathogens through their dissemination to the public, sometimes through the food chain. Four multidrug resistant Gram negative pathogens including: 2 Pseudomonas aeruginosa and 2 Proteus ...

  1. Growth of Pseudomonas fluorescens on Cassava Starch ...

    African Journals Online (AJOL)

    This involved hydrolysis of starch extracted from freshly harvested cassava tubers using enzyme-enzyme method of hydrolysis, followed by aerobic fermentation of Pseudomonas fluorescens on a mixture of the hydrolysate and nutrient media in a fermentor in batch cultures. The reducing sugar hydrolysate served as the ...

  2. Characterization of rhodanese produced by Pseudomonas ...

    African Journals Online (AJOL)

    Enzymatic remediation of polluted environment presents advantages over traditional technologies and also over microbial remediation. Extracellular rhodanese of strains of Pseudomonas aerugionosa and Bacillus brevis isolated from soil of cassava processing site were studied. Biochemical characteristics of the purified ...

  3. Production and characterization of biosurfactant from Pseudomonas ...

    African Journals Online (AJOL)

    In this present study, biosurfactant-producing microorganisms Pseudomonas aeruginosa PBSC1, was isolated from mangrove ecosystem in Pichavaram (Boat house), Tamil Nadu, India. The biosurfactant production was done using a minimal salt medium (MSM) with crude oil as the hydrocarbon. The microbial growths ...

  4. Optimization of alkaline protease production from Pseudomonas ...

    African Journals Online (AJOL)

    A protease producing bacteria was isolated from meat waste contaminated soil and identified as Pseudomonas fluorescens. Optimization of the fermentation medium for maximum protease production was carried out. The culture conditions like inoculum concentration, incubation time, pH, temperature, carbon sources, ...

  5. "Hot Tub Rash" and "Swimmer's Ear" (Pseudomonas)

    Science.gov (United States)

    ... Hot Tub Rash > Remove swimsuits and shower with soap after getting out of the water. > Clean swimsuits after getting out of the water. ... in locations that have been closed because of pollution. Pseudomonas can multiply quickly when water disinfectant levels drop, so testing your pool or ...

  6. Occurrence of Fusarium Oxysporum and Ralstonia (Pseudomonas ...

    African Journals Online (AJOL)

    The microflora associated with the root-surface of five tomato cultivars commonly cultivated in Edo State Nigeria, was investigated by inoculating serially washed 5 mm tomato root segments on potato dextrose agar (PDA) incubated at room temperature (28-30oC). Fusarium oxysporum and Ralstonia (pseudomonas) ...

  7. High pressure inactivation of Pseudomonas in black truffle - comparison with Pseudomonas fluorescens in tryptone soya broth

    Science.gov (United States)

    Ballestra, Patricia; Verret, Catherine; Cruz, Christian; Largeteau, Alain; Demazeau, Gerard; El Moueffak, Abdelhamid

    2010-03-01

    Pseudomonas is one of the most common genera in black Perigord truffle. Its inactivation by high pressure (100-500 MPa/10 min) applied on truffles at sub-zero or low temperatures was studied and compared with those of Pseudomonas fluorescens in tryptone soya broth. Pressurization of truffles at 300 MPa/4 °C reduced the bacterial count of Pseudomonas by 5.3 log cycles. Higher pressures of 400 or 500 MPa, at 4 °C or 20 °C, allowed us to slightly increase the level of destruction to the value of ca. 6.5 log cycles but did not permit us to completely inactivate Pseudomonas. The results showed a residual charge of about 10 CFU/g. Pressure-shift freezing of truffles, which consists in applying a pressure of 200 MPa/-18 °C for 10 min and then quickly releasing this pressure to induce freezing, reduced the population of Pseudomonas by 3.3 log cycles. The level of inactivation was higher than those obtained with conventional freezing. Endogenous Pseudomonas in truffle was shown to be more resistant to high pressure treatments than P. fluorescens used for inoculation of broths.

  8. Offline Software for the Mu2e Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kutschke, Robert K. [Fermilab

    2012-01-01

    The Mu2e experiment at Fermilab is in the midst of its R&D and approval processes. To aid and inform this process, a small team has developed an end-to-end Geant4-based simulation package and has developed reconstruction code that is already at the stage of an advanced prototype. Having these tools available at an early stage allows design options and tradeoffs to be studied using high level physics quantities. A key to the success of this effort has been, as much as possible, to acquire software and customize it, rather than to build it in-house.

  9. New (e,2e) studies of atomic and molecular targets

    Energy Technology Data Exchange (ETDEWEB)

    Casagrande, E M Staicu; Naja, A; Lahmam-Bennani, A [Universite de Paris-Sud XI and CNRS, Laboratoire des Collisions Atomiques et Moleculaires (UMR 8625), Bat. 351, 91405 Orsay Cedex (France); Kheifets, A S [Research School of Physical Science and Engineering, Australian National University, Canberra ACT 0200 (Australia); Madison, D H [Department of Physics, Missouri University of Science and Technology, Rolla, MO 65409-0640 (United States); Joulakian, B [Universite Paul Verlaine-Metz, Laboratoire de Physique Moleculaire et des Collisions (FR 2843), Institut de Physique, 1 rue Arago, 57078 Metz Cedex 3 (France)], E-mail: elena-magdalena.staicu-casagrande@u-psud.fr

    2008-11-01

    We report new coplanar (e,2e) measurements characterised by large energy transfer and close to minimum momentum transfer from the projectile to the target. Ionisation of the two-electron targets He and H{sub 2} is investigated under these particular kinematics. The experimental data are compared with the predictions of the most elaborate theoretical models. The obtained good agreement motivated us to extend our research to the case of more complex targets such as Ar. Comparison with the most elaborate models in the case of multi-electron targets is excellent. Destructive and constructive interference effects in the case of H{sub 2} are observed and discussed.

  10. Characterization of polar organosulfates in secondary organic aerosol from the unsaturated aldehydes 2-E-pentenal, 2-E-hexenal, and 3-Z-hexenal

    Data.gov (United States)

    U.S. Environmental Protection Agency — We show in the present study that the unsaturated aldehydes, 2-E-pentenal, 2-E-hexenal and 3-Z-hexenal, are biogenic volatile organic compound (BVOC) precursors for...

  11. Two-step Purification Method for Aging Pigments A2E and Iso-A2E Using Medium Pressure Liquid Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Il; Park, Sang Cheol [Kyunghee Univ., Seoul (Korea, Republic of); Kim, So Ra; Jang, Young Pyo [Seoul National Univ., Seoul (Korea, Republic of)

    2016-09-15

    A newly modified method for the efficient purification of A2E and iso-A2E using reverse phase silica gel resin with medium pressure liquid chromatography (MPLC) was suggested. MPLC is one of the various preparative column chromatography techniques and separation under pressure renders the use of smaller particle size resins possible and increases the diversity of available stationary phases. A simplified two-step purification method was developed for the purification of aging pigments in eye, A2E and iso-A2E. With simple two-step elution of mobile phase in reverse phase MPLC, A2E and iso-A2E were successfully purified with great efficiency compare with previous column chromatography and HPLC method. This method provides more simple, convenient, cost-effective, and less time-consuming procedure for mass purification of aging pigments A2E and iso-A2E.

  12. Triply differential (e,2e) studies of phenol

    Energy Technology Data Exchange (ETDEWEB)

    Silva, G. B. da [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Universidade Federal de Mato Grosso, Barra do Garças, MT 78600-000 (Brazil); Neves, R. F. C. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Instituto Federal do Sul de Minas Gerais, Câmpus Poços de Caldas, MG (Brazil); Departamento de Física, UFJF, Juiz de Fora, 36036-330, MG (Brazil); Chiari, L.; Jones, D. B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Ali, E.; Madison, D. H. [Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409 (United States); Ning, C. G. [Department of Physics, State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084 (China); Nixon, K. L.; Lopes, M. C. A. [Departamento de Física, UFJF, Juiz de Fora, 36036-330, MG (Brazil); Brunger, M. J., E-mail: Michael.Brunger@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2014-09-28

    We have measured (e,2e) triple differential cross sections (TDCS) for the electron-impact ionisation of phenol with coplanar asymmetrical kinematics for an incident electron energy of 250 eV. Experimental measurements of the angular distribution of the slow outgoing electrons at 20 eV are obtained when the incident electron scatters through angles of −5°, −10°, and −15°, respectively. The TDCS data are compared with calculations performed within the molecular 3-body distorted wave model. In this case, a mixed level of agreement, that was dependent on the kinematical condition being probed, was observed between the theoretical and experimental results in the binary peak region. The experimental intensity of the recoil features under all kinematical conditions was relatively small, but was still largely underestimated by the theoretical calculations.

  13. Biodegradation Of 4-Chlorobiphenyl By Pseudomonas synxantha

    Directory of Open Access Journals (Sweden)

    Dhanjal Noorpreet Inder Kaur

    2014-10-01

    Full Text Available The stabilization and disposal of polychlorinated biphenyls (PCBs from soil environment and wetland areas is of great concern for health and safety. Wetland remediation with microorganisms is an approach for treating PCBs. A bacterial strain was isolated from hydrocarbon contaminated soil of Ropar, Punjab, able to degrade PCBs under aerobic conditions. The percentage of degradation with 100 mM/ml of 4-chlorobiphenyl was up to 90%. Degradation was monitored by mass spectrometry, high performance liquid chromatography and spectrophotometrically, showing that 4-chlorobiphenyl was degraded almost completely. The bacterial strain was identified as Pseudomonas synxantha by 16sRNA sequencing method. This is the first report of 4-chlorobiphenyl degradation by Pseudomonas synxantha.

  14. Pseudomonas spp. convert metmyoglobin into deoxymyoglobin.

    Science.gov (United States)

    Motoyama, Michiyo; Kobayashi, Miho; Sasaki, Keisuke; Nomura, Masaru; Mitsumoto, Mitsuru

    2010-01-01

    Meat 'reddening' by bacteria was observed in chilled beef. To identify the reddening bacteria, isolates were inoculated onto beef and the changes in CIE L*a*b* values monitored. As a result, two Pseudomonas spp., including Pseudomonas fragi which is commonly observed in raw meat, were selected and identified as reddening bacteria. The reddening was coincidentally occurred with the appearance of slime, and the increase in thiobarbituric acid-reactive substances (TBARS) was simultaneously suppressed. In myoglobin-containing nutrient broth, it is shown spectroscopically that P. fragi converted metmyoglobin into deoxymyoglobin. It was concluded that the meat reddening was due to the formation of deoxymyoglobin, induced by the very-low-oxygen tension brought about by Pseudomonad's oxygen consumption: This oxygen depletion simultaneously suppressed TBARS increase.

  15. The immune system vs. Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Jensen, Peter Østrup; Givskov, Michael; Bjarnsholt, Thomas

    2010-01-01

    Ilya Metchnikoff and Paul Ehrlich were awarded the Nobel price in 1908. Since then, numerous studies have unraveled a multitude of mechanistically different immune responses to intruding microorganisms. However, in the vast majority of these studies, the underlying infectious agents have appeared...... the present review on the immune system vs. biofilm bacteria is focused on Pseudomonas aeruginosa (mainly because this is the most thoroughly studied), many of the same mechanisms are also seen with biofilm infections generated by other microorganisms....

  16. Extracytoplasmic function sigma factors in Pseudomonas syringae

    DEFF Research Database (Denmark)

    Kiil, Kristoffer; Oguiza, J.A.; Ussery, D.W.

    2005-01-01

    Genome analyses of the plant pathogens Pseudomonas syringae pv. tomato DC3000, pv. syringae B728a and pv. phaseolicola 1448A reveal fewer extracytoplasmic function (ECF) sigma factors than in related Pseudomonads with different lifestyles. We highlight the presence of a P. syringae-specific ECF s...... sigma factor that is an interesting target for future studies because of its potential role in the adaptation of P. syringae to its specialized phytopathogenic lifestyle....

  17. Isolation and characterization of arsenite oxidizing Pseudomonas ...

    African Journals Online (AJOL)

    A bacterium, Pseudomonas lubricans, isolated from heavy metal laden industrial wastewater, has been shown to tolerate multiple heavy metals suggesting its importance in bioremediation of industrial effluents. P. lubricans tolerated As(III) up to 3 mg ml-1, Cu2+ up to 0.7 mg ml-1, Hg2+ up to 0.4 mg ml-1, Ni2+ up to 0.4 mg ...

  18. Nosocomial outbreak of Pseudomonas aeruginosa endophthalmitis.

    Science.gov (United States)

    Mateos, I; Valencia, R; Torres, M J; Cantos, A; Conde, M; Aznar, J

    2006-11-01

    We describe an outbreak of nosocomial endophthalmitis due to a common source, which was determined to be trypan blue solution prepared in the hospital's pharmacy service. We assume that viable bacteria probably gained access to the trypan blue stock solution during cooling after autoclaving. The temporal cluster of Pseudomonas aeruginosa endophthalmitis was readily perceived on the basis of clinical and microbiological findings, and an exogenous source of contamination was unequivocally identified by means of DNA fingerprinting.

  19. High quality draft genome sequences of Pseudomonas fulva DSM 17717(T), Pseudomonas parafulva DSM 17004(T) and Pseudomonas cremoricolorata DSM 17059(T) type strains.

    Science.gov (United States)

    Peña, Arantxa; Busquets, Antonio; Gomila, Margarita; Mulet, Magdalena; Gomila, Rosa M; Reddy, T B K; Huntemann, Marcel; Pati, Amrita; Ivanova, Natalia; Markowitz, Victor; García-Valdés, Elena; Göker, Markus; Woyke, Tanja; Klenk, Hans-Peter; Kyrpides, Nikos; Lalucat, Jorge

    2016-01-01

    Pseudomonas has the highest number of species out of any genus of Gram-negative bacteria and is phylogenetically divided into several groups. The Pseudomonas putida phylogenetic branch includes at least 13 species of environmental and industrial interest, plant-associated bacteria, insect pathogens, and even some members that have been found in clinical specimens. In the context of the Genomic Encyclopedia of Bacteria and Archaea project, we present the permanent, high-quality draft genomes of the type strains of 3 taxonomically and ecologically closely related species in the Pseudomonas putida phylogenetic branch: Pseudomonas fulva DSM 17717(T), Pseudomonas parafulva DSM 17004(T) and Pseudomonas cremoricolorata DSM 17059(T). All three genomes are comparable in size (4.6-4.9 Mb), with 4,119-4,459 protein-coding genes. Average nucleotide identity based on BLAST comparisons and digital genome-to-genome distance calculations are in good agreement with experimental DNA-DNA hybridization results. The genome sequences presented here will be very helpful in elucidating the taxonomy, phylogeny and evolution of the Pseudomonas putida species complex.

  20. The effect of pseudomonas exotoxin A on cytokine production in whole blood exposed to Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Schultz, M. J.; Speelman, P.; Zaat, S. A.; Hack, C. E.; van Deventer, S. J.; van der Poll, T.

    2000-01-01

    To determine the effect of Pseudomonas aeruginosa exotoxin A (P-ExA) on cytokine production, we studied cytokine release induced by heat-killed P. aeruginosa (HKPA) in human whole blood in the presence or absence of P-ExA. P-ExA (0.01-1 microgram ml(-1)) caused a dose-dependent decrease in

  1. Stratified growth in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Werner, E.; Roe, F.; Bugnicourt, A.

    2004-01-01

    In this study, stratified patterns of protein synthesis and growth were demonstrated in Pseudomonas aeruginosa biofilms. Spatial patterns of protein synthetic activity inside biofilms were characterized by the use of two green fluorescent protein (GFP) reporter gene constructs. One construct...... of oxygen limitation in the biofilm. Oxygen microelectrode measurements showed that oxygen only penetrated approximately 50 mum into the biofilm. P. aeruginosa was incapable of anaerobic growth in the medium used for this investigation. These results show that while mature P. aeruginosa biofilms contain...

  2. Pseudomonas salegens sp. nov., a halophilic member of the genus Pseudomonas isolated from a wetland.

    Science.gov (United States)

    Amoozegar, Mohammad Ali; Shahinpei, Azadeh; Sepahy, Abbas Akhavan; Makhdoumi-Kakhki, Ali; Seyedmahdi, Shima Sadat; Schumann, Peter; Ventosa, Antonio

    2014-10-01

    A novel Gram-stain-negative, aerobic, non-endospore-forming, non-pigmented, rod-shaped, slightly halophilic bacterium, designated GBPy5(T), was isolated from aquatic plants of the Gomishan wetland, Iran. Cells of strain GBPy5(T) were motile. Growth occurred with between 1 and 10% (w/v) NaCl and the isolate grew optimally with 3% (w/v) NaCl. The optimum pH and temperature for growth of the strain were pH 8.0 and 30 °C, respectively, while it was able to grow over a pH range of 6.5-9.0 and a temperature range of 4-35 °C. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain GBPy5(T) is a member of the genus Pseudomonas forming a monophyletic branch. The novel strain exhibited 16S rRNA gene sequence similarity of 95.4% with type strains of Pseudomonas guariconensis PCAVU11(T) and Pseudomonas sabulinigri J64(T), respectively. The major cellular fatty acids of the isolate were C18:1ω7c (37.8%), C16:0 (14.9%), C16:1ω7c (12.9%), C12:0 3-OH (7.1%) and C12:0 (7.0%). The polar lipid pattern of strain GBPy5(T) comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and one phospholipid. Ubiquinone 9 (Q-9) was the predominant lipoquinone. The G+C content of the genomic DNA of strain GBPy5(T) was 59.2 mol%. On the basis of the phenotypic and phylogenetic data, strain GBPY5(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas salegens sp. nov. is proposed. The type strain is GBPy5(T) ( = IBRC-M 10762(T) = CECT 8338(T)). IUMS.

  3. Antagonistic potential of fluorescent Pseudomonas and its impact on ...

    African Journals Online (AJOL)

    This study focused on the antagonistic potential of fluorescent Pseudomonas in vitro, and its inoculation effect on growth performance of Lycopersicon esculentum in Fusarium oxysporum and Rhizoctonia solani infested soil. Biochemical characteristics of fluorescent Pseudomonas showed that all ten isolates were positive ...

  4. Genetic detection of Pseudomonas spp. in commercial Amazonian fish.

    Science.gov (United States)

    Ardura, Alba; Linde, Ana R; Garcia-Vazquez, Eva

    2013-08-29

    Brazilian freshwater fish caught from large drainages like the River Amazon represent a million ton market in expansion, which is of enormous importance for export to other continents as exotic seafood. A guarantee of bacteriological safety is required for international exports that comprise a set of different bacteria but not any Pseudomonas. However, diarrhoea, infections and even septicaemia caused by some Pseudomonas species have been reported, especially in immune-depressed patients. In this work we have employed PCR-based methodology for identifying Pseudomonas species in commercial fish caught from two different areas within the Amazon basin. Most fish caught from the downstream tributary River Tapajòs were contaminated by five different Pseudomonas species. All fish samples obtained from the River Negro tributary (Manaus markets) contained Pseudomonas, but a less diverse community with only two species. The most dangerous Pseudomonas species for human health, P. aeruginosa, was not found and consumption of these fish (from their Pseudomonas content) can be considered safe for healthy consumers. As a precautionary approach we suggest considering Pseudomonas in routine bacteriological surveys of imported seafood.

  5. Novel Targets for Treatment of Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Alhede, Morten; Alhede, Maria; Bjarnsholt, Thomas

    2014-01-01

    Pseudomonas aeruginosa causes infection in all parts of the human body. The bacterium is naturally resistant to a wide range of antibiotics. In addition to resistance mechanisms such as efflux pumps, the ability to form aggregates, known as biofilm, further reduces Pseudomonas aeruginosa’s...

  6. Interleukin-18 impairs the pulmonary host response to Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Schultz, Marc J.; Knapp, Sylvia; Florquin, Sandrine; Pater, Jennie; Takeda, Kiyoshi; Akira, Shizuo; van der Poll, Tom

    2003-01-01

    Interleukin-18 (IL-18) is a potent cytokine with many different proinflammatory activities. To study the role of IL-18 in the pathogenesis of Pseudomonas pneumonia, IL-18-deficient (IL-18(-/-)) and wild-type mice were intranasally inoculated with Pseudomonas aeruginosa. IL-18 deficiency was

  7. Interactions between biosurfactant-producing Pseudomonas and Phytophthora species

    NARCIS (Netherlands)

    Tran, H.

    2007-01-01

    Fluorescent Pseudomonas bacteria produce a wide variety of antimicrobial metabolites, including soap-like compounds referred to as biosurfactants. The results of this thesis showed that biosurfactant-producing Pseudomonas bacteria are effective in controlling Phytophthora foot rot disease of black

  8. Biosynthesis and regulation of cyclic lipopeptides in Pseudomonas fluorescens

    NARCIS (Netherlands)

    Bruijn, de I.

    2009-01-01

    Cyclic lipopeptides (CLPs) are surfactant and antibiotic metabolites produced by a variety of bacterial genera. For the genus Pseudomonas, many structurally different CLPs have been identified. CLPs play an important role in surface motility of Pseudomonas strains, but also in virulence and

  9. Typing of Pseudomonas aeruginosa strains in Norwegian cystic fibrosis patients

    DEFF Research Database (Denmark)

    Fluge, G; Ojeniyi, B; Høiby, N

    2001-01-01

    OBJECTIVES: Typing of Pseudomonas aeruginosa isolates from Norwegian cystic fibrosis (CF) patients with chronic Pseudomonas lung infection in order to see whether cross-infection might have occurred. METHODS: Isolates from 60 patients were collected during the years 1994-98, and typed by pulsed...... between cystic fibrosis patients has occurred....

  10. Energetics of binary mixed culture of Pseudomonas aeruginosa and ...

    African Journals Online (AJOL)

    Bioenergetic analysis of the growth of the binary mixed culture (Pseudomonas aeruginosa and Pseudomonas fluorescence) on phenol chemostat culture was carried out. The data were checked for consistency using carbon and available electron balances. When more than the minimum number of variables are measured, ...

  11. Energetics of binary mixed culture of Pseudomonas aeruginosa and ...

    African Journals Online (AJOL)

    Jane

    2010-12-20

    Dec 20, 2010 ... Bioenergetic analysis of the growth of the binary mixed culture (Pseudomonas aeruginosa and. Pseudomonas fluorescence) on ... biological system is widely gaining recognition (Yang et al., 1984; Solomon et al., .... Thus, by application of the covariate adjustment technique. (Solomon et al., 1985, 1994) in ...

  12. Pseudomonas Exotoxin A: optimized by evolution for effective killing

    Directory of Open Access Journals (Sweden)

    Marta eMichalska

    2015-09-01

    Full Text Available Pseudomonas Exotoxin A (PE is the most toxic virulence factor of the pathogenic bacterium Pseudomonas aeruginosa. This review describes current knowledge about the intoxication pathways of PE. Moreover, PE represents a remarkable example for pathoadaptive evolution, how bacterial molecules have been structurally and functionally optimized under evolutionary pressure to effectively impair and kill their host cells.

  13. 33 original article infections a pseudomonas aeruginosa dans un ...

    African Journals Online (AJOL)

    boaz

    institution of effective resistance surveillance and infection control measures. . Keywords: Pseudomonas aeruginosa, National Hospital Abuja, Susceptibility. INFECTIONS A PSEUDOMONAS AERUGINOSA DANS UN HOPITAL TERTIAIRE. AU NIGERIA. *Iregbu KC, Eze SO,. Département de Microbiologie Médicale and ...

  14. Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

    DEFF Research Database (Denmark)

    Johansen, H.K.; Gøtzsche, Peter C.; Johansen, Helle Krogh

    2008-01-01

    BACKGROUND: Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed. OBJECTIVES......: To assess the effectiveness of vaccination against Pseudomonas aeruginosa in cystic fibrosis. SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register using the terms vaccines AND pseudomonas (last search May 2008) and PubMed using the terms vaccin* AND cystic...... fibrosis (last search May 2008). SELECTION CRITERIA: Randomised trials (published or unpublished) comparing Pseudomonas aeruginosa vaccines (oral, parenteral or intranasal) with control vaccines or no intervention in cystic fibrosis. DATA COLLECTION AND ANALYSIS: The authors independently selected trials...

  15. Biotransformation of myrcene by Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Hashemi Elham

    2011-05-01

    Full Text Available Abstract Background Dihydrolinalool and terpineol are sources of fragrances that provide a unique volatile terpenoid alcohol of low toxicity and thus are widely used in the perfumery industry, in folk medicine, and in aromatherapy. They are important chemical constituents of the essential oil of many plants. Previous studies have concerned the biotransformation of limonene by Pseudomonas putida. The objective of this research was to study biotransformation of myrcene by Pseudomonas aeruginosa. The culture preparation was done using such variables as different microbial methods and incubation periods to obtain maximum cells of P. aeruginosa for myrcene biotransformation. Results It was found that myrcene was converted to dihydrolinalool and 2,6-dimethyloctane in high percentages. The biotransformation products were identified by Fourier-transform infrared spectroscopy (FT-IR, ultraviolet (UV analysis, gas chromatography (GC, and gas chromatography-mass spectroscopy (GC-MS. Comparison of the different incubation times showed that 3 days was more effective, the major products being 2,6-dimethyloctane (90.0% and α-terpineol (7.7% and comprising 97.7%. In contrast, the main compounds derived for an incubation time of 1.5 days were dihydrolinalool (79.5% and 2,6-dimethyloctane (9.3%, with a total yield of 88.8%.

  16. Absence of NR2E1 mutations in patients with aniridia

    DEFF Research Database (Denmark)

    Corso-Díaz, Ximena; Borrie, Adrienne E; Bonaguro, Russell

    2012-01-01

    Nuclear receptor 2E1 (NR2E1) is a transcription factor with many roles during eye development and thus may be responsible for the occurrence of certain congenital eye disorders in humans. To test this hypothesis, we screened NR2E1 for candidate mutations in patients with aniridia and other...

  17. Pseudomonas spp.: contamination sources in bulk tanks of dairy farms

    Directory of Open Access Journals (Sweden)

    Ana M.C. Vidal

    Full Text Available ABSTRACT: This study focused on isolating Pseudomonas spp. during milking process in ten dairy farms with manual and mechanical milking systems during dry and rainy seasons, and evaluating DNA homology and patterns of distribution between isolates, in order to identify main sources of milk contamination by Pseudomonas spp. A total of 167 isolates of Pseudomonas spp. were obtained from water, milkers’ hands, cows’ teats, teat cups, cooling tanks and raw milk. Bacteria of Pseudomonas spp. genus were isolated from 85 and 82 sampling points in dairy farms with manual and mechanical milking system, respectively. A significant difference (p=0.02 on Pseudomonas spp. isolation was observed among samples of surface of cows’ teats before and after pre-dipping, but no significant difference (p>0.05 was observed among milking systems or seasons. The possibility of the same Pseudomonas spp. patterns are distributed in different farms and seasons using Amplified Fragment Length Polymorphism (AFLP technique was demonstrated. Milkers’ hands, surface of cows’ teats, teat cups and cooling tanks were associated with raw milk contamination with Pseudomonas spp. on farms with manual and mechanical milking system, showing that regardless of the type of milking system and season, proper hygiene procedures of equipment, utensils and workers’ hands are essential to avoid contamination of the milk and, therefore, improve milk quality.

  18. Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

    DEFF Research Database (Denmark)

    Johansen, Helle Krogh; Gøtzsche, Peter C

    2015-01-01

    BACKGROUND: Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed. This is a......BACKGROUND: Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed....... This is an update of a previously published review. OBJECTIVES: To assess the effectiveness of vaccination against Pseudomonas aeruginosa in cystic fibrosis. SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register using the terms vaccines AND pseudomonas (last search 30...... March 2015). We previously searched PubMed using the terms vaccin* AND cystic fibrosis (last search 30 May 2013). SELECTION CRITERIA: Randomised trials (published or unpublished) comparing Pseudomonas aeruginosa vaccines (oral, parenteral or intranasal) with control vaccines or no intervention in cystic...

  19. Management and treatment of contact lens-related Pseudomonas keratitis

    Directory of Open Access Journals (Sweden)

    Willcox MD

    2012-06-01

    Full Text Available Mark DP WillcoxSchool of Optometry and Vision Science, University of New South Wales, Sydney, AustraliaAbstract: Pubmed and Medline were searched for articles referring to Pseudomonas keratitis between the years 2007 and 2012 to obtain an overview of the current state of this disease. Keyword searches used the terms "Pseudomonas" + "Keratitis" limit to "2007–2012", and ["Ulcerative" or "Microbial"] + "Keratitis" + "Contact lenses" limit to "2007–2012". These articles were then reviewed for information on the percentage of microbial keratitis cases associated with contact lens wear, the frequency of Pseudomonas sp. as a causative agent of microbial keratitis around the world, the most common therapies to treat Pseudomonas keratitis, and the sensitivity of isolates of Pseudomonas to commonly prescribed antibiotics. The percentage of microbial keratitis associated with contact lens wear ranged from 0% in a study from Nepal to 54.5% from Japan. These differences may be due in part to different frequencies of contact lens wear. The frequency of Pseudomonas sp. as a causative agent of keratitis ranged from 1% in Japan to over 50% in studies from India, Malaysia, and Thailand. The most commonly reported agents used to treat Pseudomonas keratitis were either aminoglycoside (usually gentamicin fortified with a cephalosporin, or monotherapy with a fluoroquinolone (usually ciprofloxacin. In most geographical areas, most strains of Pseudomonas sp. (≥95% were sensitive to ciprofloxacin, but reports from India, Nigeria, and Thailand reported sensitivity to this antibiotic and similar fluoroquinolones of between 76% and 90%.Keywords: Pseudomonas, keratitis, contact lens

  20. Pioglitazone, quercetin and hydroxy citric acid effect on cytochrome P450 2E1 (CYP2E1) enzyme levels in experimentally induced non alcoholic steatohepatitis (NASH).

    Science.gov (United States)

    Surapaneni, K M; Priya, V V; Mallika, J

    2014-01-01

    Non-Alcoholic Steatohepatitis (NASH) is a severe form of Non Alcoholic Fatty Liver Disease (NAFLD) spectrum, which progresses to the end stage liver disease. A common denominator in the pathogenesis of insulin resistance and nonalcoholic steatohepatitis is increased oxidative stress. Hepatic induction of the pro-oxidant enzyme Cytochrome P450 2E1 (CYP2E1) occurs in both NAFLD and type-2 diabetes. In this study, the comparative effect of pioglitazone, quercetin and hydroxy citric acid on liver CYP2E1 enzyme levels in experimentally induced NASH has been studied. The experimental protocol consists of 5 groups viz. Control (n = 6); NASH Induced (n=6); NASH + Pioglitazone (n=6); NASH + Quercetin (n=6); NASH + Hydroxy Citric Acid (n=6). CYP2E1 enzyme levels were detected in liver by immunoblot analysis in all the groups. CYP2E1 catalytic activity was increased in experimentally induced NASH group compared to control group as evidenced by the Immunoblot analysis. It revealed low CYP2E1 in the experimentally induced NASH, treated with pioglitazone, quercetin and hydroxy citric acid. Mild decrease in the levels of CYP2E1 level was observed in experimental NASH treated with pioglitazone compared to NASH group. Treatment with hydroxy citric acid also showed mild decrease in the levels of CYP2E1. On contrary to the action of pioglitazone and hydroxy citric acid, quercetin showed an approximate 2-fold decrease in the level of CYP2E1 in experimental NASH treated with quercetin compared to NASH group. Being a powerful antioxidant, quercetin offers absolute protection to liver against NASH by reducing the levels of CYP2E1 and, thereby, reducing CYP2E1 mediated oxidative stress, which is believed to be the one of the key factor in the pathogenesis of NASH. On the other hand, pioglitazone and hydroxy citric acid exerted limited effect on the levels of CYP2E1. This study showed the therapeutic value of quercetin, pioglitazone and hydroxy citric acid in treating NASH.

  1. The pseudomonas quinolone signal (PQS balances life and death in Pseudomonas aeruginosa populations.

    Directory of Open Access Journals (Sweden)

    Susanne Häussler

    Full Text Available When environmental conditions deteriorate and become inhospitable, generic survival strategies for populations of bacteria may be to enter a dormant state that slows down metabolism, to develop a general tolerance to hostile parameters that characterize the habitat, and to impose a regime to eliminate damaged members. Here, we provide evidence that the pseudomonas quinolone signal (PQS mediates induction of all of these phenotypes. For individual cells, PQS, an interbacterial signaling molecule of Pseudomonas aeruginosa, has both deleterious and beneficial activities: on the one hand, it acts as a pro-oxidant and sensitizes the bacteria towards oxidative and other stresses and, on the other, it efficiently induces a protective anti-oxidative stress response. We propose that this dual function fragments populations into less and more stress tolerant members which respond differentially to developing stresses in deteriorating habitats. This suggests that a little poison may be generically beneficial to populations, in promoting survival of the fittest, and in contributing to bacterial multi-cellular behavior. It further identifies PQS as an essential mediator of the shaping of the population structure of Pseudomonas and of its response to and survival in hostile environmental conditions.

  2. Pseudomonas-induced corneal ulcers associated with contaminated eye mascaras.

    Science.gov (United States)

    Wilson, L A; Ahearn, D G

    1977-07-01

    Seven Pseudomonas-induced corneal ulcers were associated with the use of four brands of mascara contaminated with P. aeruginosa. In laboratory studies, preservative systems of three of the four brands were inadequate in comparison with a control mascara of known antimicrobial activity. If the corneal epithelium is scratched during the application of mascara, particularly if the applicator is old, the cornea should be treated immediately and the mascara cultured to detect Pseudomonas. The high incidence of recurrent corneal ulceration in cases of Pseudomonas-induced keratitis indicates that initial chemotherapy should be intensive and maintained until the lesion stabilizes.

  3. Targeting quorum sensing in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Jakobsen, Tim Holm; Bjarnsholt, Thomas; Jensen, Peter Østrup

    2013-01-01

    Bacterial resistance to conventional antibiotics combined with an increasing acknowledgement of the role of biofilms in chronic infections has led to a growing interest in new antimicrobial strategies that target the biofilm mode of growth. In the aggregated biofilm mode, cell-to-cell communication...... systems involved in the process known as quorum sensing regulate coordinated expression of virulence with immune shielding mechanisms and antibiotic resistance. For two decades, the potential of interference with quorum sensing by small chemical compounds has been investigated with the aim of developing...... alternative antibacterial strategies. Here, we review state of the art research of quorum sensing inhibitors against the opportunistic human pathogen Pseudomonas aeruginosa, which is found in a number of biofilm-associated infections and identified as the predominant organism infecting the lungs of cystic...

  4. Complement activation by Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Jensen, E T; Kharazmi, A; Garred, P

    1993-01-01

    In chronic infections, such as the bronchopulmonary Pseudomonas aeruginosa infection in cystic fibrosis (CF) patients, bacteria persist despite an intact host immune defense and frequent antibiotic treatment. An important reason for the persistence of the bacteria is their capacity for the biofilm...... mode of growth. In this study we investigated the role of biofilms in activation of complement, a major contributor to the inflammatory process. Complement activation by P. aeruginosa was examined in a complement consumption assay, production of C3 and factor B conversion products assessed by crossed...... immuno-electrophoresis, C5a generation tested by a PMN chemotactic assay, and terminal complement complex formation measured by ELISA. Two of the four assays showed that P. aeruginosa grown in biofilm activated complement less than planktonic bacteria, and all assays showed that activation by intact...

  5. Rhamnolipid Biosurfactants Produced by Pseudomonas Species

    Directory of Open Access Journals (Sweden)

    Banu Kaskatepe

    Full Text Available ABSTRACT: Surfactants are chemical products widely used in our daily life in toothpaste and other personal hygiene and cosmetic products, and in several industries. Biosurfactants are surfactants of biological origin that can be produced by microorganisms and have many advantages, such as low toxicity and high biodegradability, compared to synthetic counterparts. Unfortunately, high production costs limit the use of biosurfactants. Low-cost production is the most important factor for biosurfactants to be able to compete in the global market place. This review presents general information on rhamnolipid biosurfactant produced by Pseudomonas species, as well as on their production and applications. In addition, industrial products and their wastes used for rhamnolipid production are reviewed in detail based on recent studies.

  6. Cell death in Pseudomonas aeruginosa biofilm development

    DEFF Research Database (Denmark)

    Webb, J.S.; Thompson, L.S.; James, S.

    2003-01-01

    Bacteria growing in biofilms often develop multicellular, three-dimensional structures known as microcolonies. Complex differentiation within biofilms of Pseudomonas aeruginosa occurs, leading to the creation of voids inside microcolonies and to the dispersal of cells from within these voids....... However, key developmental processes regulating these events are poorly understood. A normal component of multicellular development is cell death. Here we report that a repeatable pattern of cell death and lysis occurs in biofilms of P. aeruginosa during the normal course of development. Cell death...... occurred with temporal and spatial organization within biofilms, inside microcolonies, when the biofilms were allowed to develop in continuous-culture flow cells. A subpopulation of viable cells was always observed in these regions. During the onset of biofilm killing and during biofilm development...

  7. Cooperative production of siderophores by Pseudomonas aeruginosa.

    Science.gov (United States)

    Harrison, Freya; Buckling, Angus

    2009-01-01

    The production of iron-scavenging siderophores by the opportunistic animal pathogen Pseudomonas aeruginosa is a textbook example of public goods cooperation. This trait provides an excellent model system with which to study cooperation. Further, the links between siderophore production and P. aeruginosa virulence allow us to investigate how pathogen ecology, social behaviour and pathology might be connected. We present here the results of basic research on the evolution and ecology of siderophore cooperation in this species. In particular, we explore the effects of population and community structure, iron regime and genomic mutation rate on the relative success of siderophore cooperators and cheats. We also present preliminary data on the links between siderophore production and another clinically-relevant social trait, biofilm formation. It is our hope that more realistic laboratory studies of siderophore cooperation in P. aeruginosa will eventually cast light on the roles played by social traits in long-term microbial infections.

  8. Pseudomonas aeruginosa endophthalmitis masquerading as chronic uveitis

    Directory of Open Access Journals (Sweden)

    Kalpana Badami Nagaraj

    2013-01-01

    Full Text Available A 65-year-old male presented with decreased vision in the left eye of 15-day duration after having undergone an uneventful cataract surgery 10 months back. He had been previously treated with systemic steroids for recurrent uveitis postoperatively on three occasions in the same eye. B-scan ultrasonography showed multiple clumplike echoes suggestive of vitreous inflammation. Aqueous tap revealed Pseudomonas aeruginosa sensitive to ciprofloxacin. The patient was treated with intravitreal ciprofloxacin and vancomycin along with systemic ciprofloxacin with good clinical response. Even a virulent organism such as P.aeruginosa can present as a chronic uveitis, which, if missed, can lead to a delay in accurate diagnosis and appropriate management.

  9. Pseudomonas aeruginosa biofilms in cystic fibrosis

    DEFF Research Database (Denmark)

    Høiby, Niels; Ciofu, Oana; Bjarnsholt, Thomas

    2010-01-01

    of mutations, slow growth and adaptation of the bacteria to the conditions in the lungs, and to antibiotic therapy. Low bacterial metabolic activity and increase of doubling times of the bacterial cells in CF lungs are responsible for some of the tolerance to antibiotics. Conventional resistance mechanisms......, such as chromosomal ß-lactamase, upregulated efflux pumps, and mutations of antibiotic target molecules in the bacteria, also contribute to the survival of P. aeruginosa biofilms. Biofilms can be prevented by early aggressive antibiotic prophylaxis or therapy, and they can be treated by chronic suppressive therapy.......The persistence of chronic Pseudomonas aeruginosa lung infections in cystic fibrosis (CF) patients is due to biofilm-growing mucoid (alginate-producing) strains. A biofilm is a structured consortium of bacteria, embedded in a self-produced polymer matrix consisting of polysaccharide, protein...

  10. Biosynthesis of pyocyanin pigment by Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    M.Z. El-Fouly

    2015-01-01

    Full Text Available Sixty-three isolates belonging to the genus Pseudomonas were isolated from different environmental sources including; soil, water and clinical specimens. Twenty out of them were identified as Pseudomonas aeruginosa and individually screened for pyocyanin production. P. aeruginosa R1; isolated from rice-cultivated soil and P. aeruginosa U3 selected from clinical specimen (Urinary tract infection were the highest pyocyanin producers; pyocyanin production reached 9.3 and 5.9 μg/ml, respectively on synthetic glucose supplemented nutrient medium (GSNB. The identification of both selected strains (P. aeruginosa R1 and P. aeruginosa U3 was confirmed by 16S rRNA, the similarity with other strains available in database was 97% (with P. aeruginosa FPVC 14 and 94% (with P. aeruginosa 13.A, respectively. P. aeruginosa R1 and P. aeruginosa U3 are accessed at gene bank with accession numbers KM924432 and KM603511, in the same order. Pyocyanin was extracted by standard methods, purified by column chromatography and characterized by UV-Vis absorption, mass spectrometry and nuclear magnetic resonance. The antimicrobial activity of purified pyocyanin against multi-drug resistant microbes was investigated; the efficiency of pyocyanin was more obvious in Gram +ve bacteria than Gram−ve bacteria and yeast. To reduce the cost of pyocyanin production, a new conventional medium based on cotton seed meal supplemented with peptone was designed. The pyocyanin production of both selected strains P. aeruginosa R1 and P. aeruginosa U3 using the new medium is increased by 30.1% and 17.2%, respectively in comparison with synthetic GSNB medium, while the cost of production process is reduced by 56.7%.

  11. Functional Analysis of Genes for Biosynthesis of Pyocyanin and Phenazine-1-Carboxamide from Pseudomonas aeruginosa PAO1

    Science.gov (United States)

    Mavrodi, Dmitri V.; Bonsall, Robert F.; Delaney, Shannon M.; Soule, Marilyn J.; Phillips, Greg; Thomashow, Linda S.

    2001-01-01

    Two seven-gene phenazine biosynthetic loci were cloned from Pseudomonas aeruginosa PAO1. The operons, designated phzA1B1C1D1E1F1G1 and phzA2B2C2D2E2F2G2, are homologous to previously studied phenazine biosynthetic operons from Pseudomonas fluorescens and Pseudomonas aureofaciens. Functional studies of phenazine-nonproducing strains of fluorescent pseudomonads indicated that each of the biosynthetic operons from P. aeruginosa is sufficient for production of a single compound, phenazine-1-carboxylic acid (PCA). Subsequent conversion of PCA to pyocyanin is mediated in P. aeruginosa by two novel phenazine-modifying genes, phzM and phzS, which encode putative phenazine-specific methyltransferase and flavin-containing monooxygenase, respectively. Expression of phzS alone in Escherichia coli or in enzymes, pyocyanin-nonproducing P. fluorescens resulted in conversion of PCA to 1-hydroxyphenazine. P. aeruginosa with insertionally inactivated phzM or phzS developed pyocyanin-deficient phenotypes. A third phenazine-modifying gene, phzH, which has a homologue in Pseudomonas chlororaphis, also was identified and was shown to control synthesis of phenazine-1-carboxamide from PCA in P. aeruginosa PAO1. Our results suggest that there is a complex pyocyanin biosynthetic pathway in P. aeruginosa consisting of two core loci responsible for synthesis of PCA and three additional genes encoding unique enzymes involved in the conversion of PCA to pyocyanin, 1-hydroxyphenazine, and phenazine-1-carboxamide. PMID:11591691

  12. Characterization of Pseudomonas aeruginosa PB112 (JN996498 ...

    African Journals Online (AJOL)

    Characterization of Pseudomonas aeruginosa PB112 (JN996498) isolated from infected Labeo bata (Hamilton) by 16S rRNA gene sequence analysis and fatty acid methyl ester (FAME) analysis. Somerita Panda, PK Bandyopadhyay, SN Chatterjee ...

  13. The Enzymes of the Ammonia Assimilation in Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Janssen, Dick B.; Camp, Huub J.M. op den; Leenen, Pieter J.M.; Drift, Chris van der

    1980-01-01

    Glutamine synthetase from Pseudomonas aeruginosa is regulated by repression/derepression of enzyme synthesis and by adenylylation/deadenylylation control. High levels of deadenylylated biosynthetically active glutamine synthetase were observed in cultures growing with limiting amounts of nitrogen

  14. Resistance patterns of Pseudomonas aeruginosa isolated from HIV ...

    African Journals Online (AJOL)

    negative bacilli in patients with impaired host defences emphasizes the need for information on the antibiotic susceptibility of the organisms that infects such patients. Pseudomonas aeruginosa are becoming increasingly resistant to ...

  15. Caenorhabditis elegans reveals novel Pseudomonas aeruginosa virulence mechanism

    NARCIS (Netherlands)

    Utari, Putri Dwi; Quax, Wim J.

    The susceptibility of Caenorhabditis elegans to different virulent phenotypes of Pseudomonas aeruginosa makes the worms an excellent model for studying host-pathogen interactions. Including the recently described liquid killing, five different killing assays are now available offering superb

  16. Pseudomonas aeruginosa Dose-Response and Bathing Water Infection

    Science.gov (United States)

    Pseudomonas aeruginosa is the most commonly identified opportunistic pathogen associated with pool acquired bather disease. To better understand why this microorganism poses this protracted problem we recently appraised P. aeruginosa pool risk management. Much is known about the ...

  17. Pseudomonas Folliculitis Associated with Use of Hot Tubs and Spas.

    Science.gov (United States)

    Ramsey, Michael L.

    1989-01-01

    Discusses the history, etiology, diagnosis, histopathology, treatment, and prevention of Pseudomonas Folliculitis, an increasingly common skin infection contracted in hot tubs and, to some extent, in swimming pools. (Author/SM)

  18. Sequencing and characterization of Pseudomonas aeruginosa phage JG004

    National Research Council Canada - National Science Library

    Garbe, Julia; Bunk, Boyke; Rohde, Manfred; Schobert, Max

    2011-01-01

    .... Pseudomonas aeruginosa. For an effective use of bacteriophages as antimicrobial agents, it is important to understand phage biology but also genes of the bacterial host essential for phage infection...

  19. Alginate overproduction affects Pseudomonas aeruginosa biofilm structure and function

    DEFF Research Database (Denmark)

    Hentzer, Morten; Teitzel, G.M.; Balzer, G.J.

    2001-01-01

    During the course of chronic cystic fibrosis (CF) infections, Pseudomonas aeruginosa undergoes a conversion to a mucoid phenotype, which is characterized by overproduction of the exopolysaccharide alginate. Chronic P. aeruginosa infections involve surface-attached, highly antibiotic-resistant com...

  20. Functional bacterial amyloid increases Pseudomonas biofilm hydrophobicity and stiffness

    DEFF Research Database (Denmark)

    Zeng, Guanghong; Vad, Brian S; Dueholm, Morten S

    2015-01-01

    hydrophobicity and mechanical properties. Using atomic force microscopy imaging and force spectroscopy, we show that the amyloid renders individual cells more resistant to drying and alters their interactions with hydrophobic probes. Importantly, amyloid makes Pseudomonas more hydrophobic and increases biofilm...

  1. New strategies for genetic engineering Pseudomonas syringae using recombination

    Science.gov (United States)

    Here we report that DNA oligonucleotides (oligos) introduced directly into bacteria by electroporation can recombine with the bacterial chromosome. This phenomenon was identified in Pseudomonas syringae and we subsequently found that Escherichia coli, Salmonella typhimurium and Shigella flexneri are...

  2. Infectious conjunctivitis caused by Pseudomonas aeruginosa isolated from a bathroom

    National Research Council Canada - National Science Library

    Eguchi, Hiroshi; Miyamoto, Tatsuro; Kuwahara, Tomomi; Mitamura, Sayaka; Mitamura, Yoshinori

    2013-01-01

    .... The purpose of this report is to describe a case of suture-related conjunctivitis caused by Pseudomonas aeruginosa for which we identified the transmission route using pulsed-field gel electrophoresis (PFGE...

  3. Characterization of Glutamine-Requiring Mutants of Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Janssen, Dick B.; Joosten, Han M.L.J.; Herst, Patricia M.; Drift, Chris van der

    1982-01-01

    Revertants were isolated from a glutamine-requiring mutant of Pseudomonas aeruginosa PAO. One strain showed thermosensitive glutamine requirement and formed thermolabile glutamine synthetase, suggesting the presence of a mutation in the structural gene for glutamine synthetase. The mutation

  4. Isolation of chlorhexidine-resistant Pseudomonas aeruginosa from clinical lesions.

    OpenAIRE

    Nakahara, H; Kozukue, H

    1982-01-01

    The chlorhexidine resistance of 317 strains of Pseudomonas aeruginosa isolated from hospital patients was determined. The distribution pattern of their susceptibility to chlorhexidine clearly revealed two peaks, and the frequency of resistance to chlorhexidine was 84.2%.

  5. Hyperbaric oxygen sensitizes anoxic Pseudomonas aeruginosa biofilm to ciprofloxacin

    DEFF Research Database (Denmark)

    Kolpen, Mette; Lerche, Christian J; Kragh, Kasper Nørskov

    2017-01-01

    Chronic Pseudomonas aeruginosa lung infection is characterized by the presence of endobronchial antibiotic-tolerant biofilm subject to strong oxygen (O2) depletion due to the activity of surrounding polymorphonuclear leukocytes. The exact mechanisms affecting the antibiotic susceptibility of biof...

  6. A study on nitrogen removal efficiency of Pseudomonas stutzeri ...

    African Journals Online (AJOL)

    USER

    2010-02-08

    Feb 8, 2010 ... 1College of Environmental Science and Engineering, South China University of Technology, Guangzhou Higher. Education Mega Centre, Panyu District, ... Key words: Anaerobic/anoxic/oxic treatment process, reaction condition, denitrification, nitrification, nitrogen removal, Pseudomonas stutzeri.

  7. Plant perceptions of plant growth-promoting Pseudomonas.

    OpenAIRE

    Preston, Gail M

    2004-01-01

    Plant-associated Pseudomonas live as saprophytes and parasites on plant surfaces and inside plant tissues. Many plant-associated Pseudomonas promote plant growth by suppressing pathogenic micro-organisms, synthesizing growth-stimulating plant hormones and promoting increased plant disease resistance. Others inhibit plant growth and cause disease symptoms ranging from rot and necrosis through to developmental dystrophies such as galls. It is not easy to draw a clear distinction between pathoge...

  8. Biodegradasi Petroleum dan Hidrokarbon Eikosana oleh Isolat Bakteri Pseudomonas aeruginosa

    OpenAIRE

    Faiqah Umar

    2015-01-01

    Biodegradation of petroleum and hydrocarbon eicosane by Pseudomonas aeruginosa isolate. Hydrocarbon are important environmental contaminants in soil and water. These compounds have a potential risk to human health, as many of them are carsinogenic and toxic to marine organisms such as diatome, gasthrophode, mussel, and fish. The purpose of this research was to know the ability of Pseudomonas aeruginosa to degradate the hydrocarbon (petroleum Hundill and eicosane) substrate. Growing test used ...

  9. The Role of CYP2E1 in the Drug Metabolism or Bioactivation in the Brain

    Directory of Open Access Journals (Sweden)

    W. A. García-Suástegui

    2017-01-01

    Full Text Available Organisms have metabolic pathways that are responsible for removing toxic agents. We always associate the liver as the major organ responsible for detoxification of the body; however this process occurs in many tissues. In the same way, as in the liver, the brain expresses metabolic pathways associated with the elimination of xenobiotics. Besides the detoxifying role of CYP2E1 for compounds such as electrophilic agents, reactive oxygen species, free radical products, and the bioactivation of xenobiotics, CYP2E1 is also related in several diseases and pathophysiological conditions. In this review, we describe the presence of phase I monooxygenase CYP2E1 in regions of the brain. We also explore the conditions where protein, mRNA, and the activity of CYP2E1 are induced. Finally, we describe the relation of CYP2E1 in brain disorders, including the behavioral relations for alcohol consumption via CYP2E1 metabolism.

  10. Effect of osmotic stress on plant growth promoting Pseudomonas spp.

    Science.gov (United States)

    Sandhya, V; Ali, Sk Z; Venkateswarlu, B; Reddy, Gopal; Grover, Minakshi

    2010-10-01

    In this study we isolated and screened drought tolerant Pseudomonas isolates from arid and semi arid crop production systems of India. Five isolates could tolerate osmotic stress up to -0.73 MPa and possessed multiple PGP properties such as P-solubilization, production of phytohormones (IAA, GA and cytokinin), siderophores, ammonia and HCN however under osmotic stress expression of PGP traits was low compared to non-stressed conditions. The strains were identified as Pseudomonas entomophila, Pseudomonas stutzeri, Pseudomonas putida, Pseudomonas syringae and Pseudomonas monteilli respectively on the basis of 16S rRNA gene sequence analysis. Osmotic stress affected growth pattern of all the isolates as indicated by increased mean generation time. An increase level of intracellular free amino acids, proline, total soluble sugars and exopolysaccharides was observed under osmotic stress suggesting bacterial response to applied stress. Further, strains GAP-P45 and GRFHYTP52 showing higher levels of EPS and osmolytes (amino acids and proline) accumulation under stress as compared to non-stress conditions, also exhibited higher expression of PGP traits under stress indicating a relationship between stress response and expression of PGP traits. We conclude that isolation and screening of indigenous, stress adaptable strains possessing PGP traits can be a method for selection of efficient stress tolerant PGPR strains.

  11. Characterization of polar organosulfates in secondary organic aerosol from the unsaturated aldehydes 2-E-pentenal, 2-E-hexenal, and 3-Z-hexenal

    Directory of Open Access Journals (Sweden)

    M. S. Shalamzari

    2016-06-01

    Full Text Available We show in the present study that the unsaturated aldehydes 2-E-pentenal, 2-E-hexenal, and 3-Z-hexenal are biogenic volatile organic compound (BVOC precursors for polar organosulfates with molecular weights (MWs 230 and 214, which are also present in ambient fine aerosol from a forested site, i.e., K-puszta, Hungary. These results complement those obtained in a previous study showing that the green leaf aldehyde 3-Z-hexenal serves as a precursor for MW 226 organosulfates. Thus, in addition to isoprene, the green leaf volatiles (GLVs 2-E-hexenal and 3-Z-hexenal, emitted due to plant stress (mechanical wounding or insect attack, and 2-E-pentenal, a photolysis product of 3-Z-hexenal, should be taken into account for secondary organic aerosol and organosulfate formation. Polar organosulfates are of climatic relevance because of their hydrophilic properties and cloud effects. Extensive use was made of organic mass spectrometry (MS and detailed interpretation of MS data (i.e., ion trap MS and accurate mass measurements to elucidate the chemical structures of the MW 230, 214 and 170 organosulfates formed from 2-E-pentenal and indirectly from 2-E-hexenal and 3-Z-hexenal. In addition, quantum chemical calculations were performed to explain the different mass spectral behavior of 2,3-dihydroxypentanoic acid sulfate derivatives, where only the isomer with the sulfate group at C-3 results in the loss of SO3. The MW 214 organosulfates formed from 2-E-pentenal are explained by epoxidation of the double bond in the gas phase and sulfation of the epoxy group with sulfuric acid in the particle phase through the same pathway as that proposed for 3-sulfooxy-2-hydroxy-2-methylpropanoic acid from the isoprene-related α,β-unsaturated aldehyde methacrolein in previous work (Lin et al., 2013. The MW 230 organosulfates formed from 2-E-pentenal are tentatively explained by a novel pathway, which bears features of the latter pathway but introduces an additional hydroxyl

  12. Characterization of polar organosulfates in secondary organic aerosol from the unsaturated aldehydes 2-E-pentenal, 2-E-hexenal, and 3-Z-hexenal

    Science.gov (United States)

    Safi Shalamzari, Mohammad; Vermeylen, Reinhilde; Blockhuys, Frank; Kleindienst, Tadeusz E.; Lewandowski, Michael; Szmigielski, Rafal; Rudzinski, Krzysztof J.; Spólnik, Grzegorz; Danikiewicz, Witold; Maenhaut, Willy; Claeys, Magda

    2016-06-01

    We show in the present study that the unsaturated aldehydes 2-E-pentenal, 2-E-hexenal, and 3-Z-hexenal are biogenic volatile organic compound (BVOC) precursors for polar organosulfates with molecular weights (MWs) 230 and 214, which are also present in ambient fine aerosol from a forested site, i.e., K-puszta, Hungary. These results complement those obtained in a previous study showing that the green leaf aldehyde 3-Z-hexenal serves as a precursor for MW 226 organosulfates. Thus, in addition to isoprene, the green leaf volatiles (GLVs) 2-E-hexenal and 3-Z-hexenal, emitted due to plant stress (mechanical wounding or insect attack), and 2-E-pentenal, a photolysis product of 3-Z-hexenal, should be taken into account for secondary organic aerosol and organosulfate formation. Polar organosulfates are of climatic relevance because of their hydrophilic properties and cloud effects. Extensive use was made of organic mass spectrometry (MS) and detailed interpretation of MS data (i.e., ion trap MS and accurate mass measurements) to elucidate the chemical structures of the MW 230, 214 and 170 organosulfates formed from 2-E-pentenal and indirectly from 2-E-hexenal and 3-Z-hexenal. In addition, quantum chemical calculations were performed to explain the different mass spectral behavior of 2,3-dihydroxypentanoic acid sulfate derivatives, where only the isomer with the sulfate group at C-3 results in the loss of SO3. The MW 214 organosulfates formed from 2-E-pentenal are explained by epoxidation of the double bond in the gas phase and sulfation of the epoxy group with sulfuric acid in the particle phase through the same pathway as that proposed for 3-sulfooxy-2-hydroxy-2-methylpropanoic acid from the isoprene-related α,β-unsaturated aldehyde methacrolein in previous work (Lin et al., 2013). The MW 230 organosulfates formed from 2-E-pentenal are tentatively explained by a novel pathway, which bears features of the latter pathway but introduces an additional hydroxyl group at the

  13. [Mechanism of cyanide and thiocyanate decomposition by an association of Pseudomonas putida and Pseudomonas stutzeri strains].

    Science.gov (United States)

    Grigor'eva, N V; Kondrat'eva, T F; Krasil'nikova, E N; Karavaĭko, G I

    2006-01-01

    The intermediate and terminal products of cyanide and thiocyanate decomposition by individual strains of the genus Pseudomonas, P. putida strain 21 and P. stutzeri strain 18, and by their association were analyzed. The activity of the enzymes of nitrogen and sulfur metabolism in these strains was compared with that of the collection strains P. putida VKM B-2187T and P. stutzeri VKM B-975T. Upon the introduction of CN- and SCN- into cell suspensions of strains 18 and 21 in phosphate buffer (pH 8.8), the production of NH4+ was observed. Due to the high rate of their utilization, NH3, NH4+, and CNO- were absent from the culture liquids of P. putida strain 21 and P. stutzeri strain 18 grown with CN- or SCN-. Both Pseudomonas strains decomposed SCN- via cyanate production. The cyanase activity was 0.75 micromol/(min mg protein) for P. putida strain 21 and 1.26 micromol/(min mg protein) for P. stutzeri strain 18. The cyanase activity was present in the cells grown with SCN- but absent in cells grown with NH4+. Strain 21 of P. putida was a more active CN- decomposer than strain 18 of P. stutzeri. Ammonium and CO2 were the terminal nitrogen and carbon products of CN- and SCN- decomposition. The terminal sulfur products of SCN- decomposition by P. stutzeri strain 18 and P. putida strain 21 were thiosulfate and tetrathionate, respectively. The strains utilized the toxic compounds in the anabolism only, as sources of nitrogen (CN- and SCN-) and sulfur (SCN-). The pathway of thiocyanate decomposition by the association of bacteria of the genus Pseudomonas is proposed based on the results obtained.

  14. Microarray-based analysis and clinical validation identify ubiquitin-conjugating enzyme E2E1 (UBE2E1 as a prognostic factor in acute myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Hongmei Luo

    2016-11-01

    Full Text Available Abstract Background Previous research suggested that single gene expression might be correlated with acute myeloid leukemia (AML survival. Therefore, we conducted a systematical analysis for AML prognostic gene expressions. Methods We performed a microarray-based analysis for correlations between gene expression and adult AML overall survival (OS using datasets GSE12417 and GSE8970. Positive findings were validated in an independent cohort of 50 newly diagnosed, non-acute promyelocytic leukemia (APL AML patients by quantitative RT-PCR and survival analysis. Results Microarray-based analysis suggested that expression of eight genes was each associated with 1-year and 3-year AML OS in both GSE12417 and GSE8970 datasets (p < 0.05. Next, we validated our findings in an independent cohort of AML samples collected in our hospital. We found that ubiquitin-conjugating enzyme E2E1 (UBE2E1 expression was adversely correlated with AML survival (p = 0.04. Multivariable analysis showed that UBE2E1 high patients had a significant shorter OS and shorter progression-free survival after adjusting other known prognostic factors (p = 0.03. At last, we found that UBE2E1 expression was negatively correlated with patients’ response to induction chemotherapy (p < 0.05. Conclusions In summary, we demonstrated that UBE2E1 expression was a novel prognostic factor in adult, non-APL AML patients.

  15. Biosorpsi Logam Zn Pada Limbah Sintetik Menggunakan Biomassa Campuran Pseudomonas aeruginosa dan Pseudomonas sp

    Directory of Open Access Journals (Sweden)

    Hidayati Hidayati

    2013-12-01

    Full Text Available Zinc is one of the heavy metals that could be harmful for environment. This metal usually arises from industrial activities. Biosorption of zinc in synthetic waste was conducted using biomass mixture of Pseudomonas aeruginosa and Pseudomonas sp. This research aims to determine the zinc adsorption capacity of the biomass in synthetic waste water. Zinc biosorption was performed at pH 4, room temperature and stirring 800 rpm. Variation of contact time used was 30, 60 and 120 min; and the amount of biomass used was 0.01 g, 0.02 g, 0.03 g, 0.04 g and 0.05 g. The highest zinc biosorption capacity was obtained 25.43% at the time of 120 minutes and the amount of biomass used 0.01 g. The optimum condition for biomass biosorption and removal capacity based on the correlation between experimental data and mathematical models was obtained with the addition of 0.04 g of biomass with correlation coefficient (R 1 and 0,965 respectively.ABSTRAK Salah satu logam berat yang berbahaya dari hasil kegiatan industri adalah logam Zn (seng. Biosorpsi logam Zn pada limbah sintetik dilakukan dengan menggunakan biomassa campuran Pseudomonas aeruginosa dan Pseudomonas sp. Penelitian ini bertujuan untuk mengetahui kapasitas biomassa dalam mengadsorpsi logam Zn pada limbah sintetik. Biosorpsi logam Zn dilakukan pada kondisi pH 4, temperatur ruang dan pengadukan 800 rpm. Variasi waktu kontak dilakukan pada 30, 60 dan 120 menit  dan menggunakan jumlah biomassa 0,01 g, 0,02 g, 0,03 g, 0,04 g  dan 0,05 g. Kapasitas biosorpsi logam Zn tertinggi diperoleh sebesar 25,43% pada waktu 120 menit dengan jumlah biomassa 0,01 g. Kondisi optimum biosorpsi logam Zn berdasarkan korelasi antara data eksperimen dan model matematika diperoleh pada penambahan jumlah biomassa sebesar 0,04 g baik untuk kapasitas biosorpsi logam Zn maupun efisiensi removal logam Zn dengan nilai koefisien korelasi (R2 masing-masing adalah 1 dan 0,965.

  16. A systematic evaluation of microRNAs in regulating human hepatic CYP2E1

    Science.gov (United States)

    Wang, Yong; Yu, Dianke; Tolleson, William H.; Yu, Li-Rong; Green, Bridgett; Zeng, Linjuan; Chen, Yinting; Chen, Si; Ren, Zhen; Guo, Lei; Tong, Weida; Guan, Huaijin; Ning, Baitang

    2017-01-01

    Cytochrome P450 2E1 (CYP2E1) is an important drug metabolizing enzyme for processing numerous xenobiotics in the liver, including acetaminophen and ethanol. Previous studies have shown that microRNAs (miRNAs) can suppress CYP2E1 expression by binding to the 3′-untranslated region (3′-UTR) of its transcript. However, a systematic analysis of CYP2E1 regulation by miRNAs has not been described. Here, we applied in silico, in vivo, and in vitro approaches to investigate miRNAs involved in the regulation of CYP2E1. Initially, potential miRNA binding sites in the CYP2E1 mRNA transcript were identified and screened using in silico methods. Next, inverse correlations were found in human liver samples between the expression of CYP2E1 mRNA and the levels of two miRNA species, hsa-miR-214-3p and hsa-miR-942-5p. In a HepG2-derived CYP2E1 over-expression cell model, hsa-miR-214-3p exhibited strong suppression of CYP2E1 expression by targeting the coding region of its mRNA transcript, but hsa-miR-942-5p did not inhibit CYP2E1 levels. Electrophoretic mobility shift assays confirmed that hsa-miR-214-3p recruited other cellular protein factors to form stable complexes with specific sequences present in the CYP2E1 mRNA open reading frame. Transfection of HepaRG cells with hsa-miR-214-3p mimics inhibited expression of the endogenous CYP2E1 gene. Further, hsa-miR-214-3p mimics partially blocked ethanol-dependent increases in CYP2E1 mRNA and protein levels in HepG2 cells and they reduced the release of alanine aminotransferase from CYP2E1-overexpressing HepG2 cells exposed to acetaminophen. These results substantiate the suppressing effect of hsa-miR-214-3p on CYP2E1 expression. PMID:28438567

  17. Antivirulence activity of azithromycin in Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Francesco eImperi

    2014-04-01

    Full Text Available Antibiotics represent our bulwark to combat bacterial infections, but the spread of antibiotic resistance compromises their clinical efficacy. Alternatives to conventional antibiotics are urgently needed in order to complement the existing antibacterial arsenal. The macrolide antibiotic azithromycin (AZM provides a paradigmatic example of an unconventional antibacterial drug. Besides its growth-inhibiting activity, AZM displays potent anti-inflammatory properties, as well as antivirulence activity on some intrinsically resistant bacteria, such as Pseudomonas aeruginosa. In this bacterium, the antivirulence activity of AZM mainly relies on its ability to interact with the ribosome, resulting in direct and/or indirect repression of specific subsets of genes involved in virulence, quorum sensing, biofilm formation and intrinsic antibiotic resistance. Both clinical experience and clinical trials have shown the efficacy of AZM in the treatment of chronic pulmonary infections caused by P. aeruginosa. The aim of this review is to combine results from laboratory studies with evidence from clinical trials in order to unify the information on the in vivo mode of action of AZM in P. aeruginosa infection.

  18. Bioadsorption characteristics of Pseudomonas aeruginosa PAOI

    Directory of Open Access Journals (Sweden)

    Kőnig-Péter Anikó

    2014-01-01

    Full Text Available Biosorption of Cd(II and Pb(II ions from aqueous solution using lyophilized Pseudomonas aeruginosa (PAOI cells were observed under various experimental conditions. The effect of pH, initial metal concentration, equilibration time and temperature on bioadsorption was investigated. The optimum pH value for Pb(II adsorption was found to be 5.0, and for Cd(II 5.0 − 6.0. The Pb(II and Cd(II bioadsorption equilibrium were analyzed by using Freundlich and Langmuir model using nonlinear least-squares estimation. The experimental maximum uptake capacity of Pb(II and Cd(II was estimated to be 164 mg g-1 and 113 mg g-1, respectively. For biosorption kinetic study the pseudo second-order kinetic model was applied at various temperatures. The temperature had no significant effect on Pb(II bioadsorption. In case of Cd(II bioadsorption the adsorbed amount decreased with increasing temperature.

  19. Benzoate transport in Pseudomonas putida CSV86.

    Science.gov (United States)

    Choudhary, Alpa; Purohit, Hemant; Phale, Prashant S

    2017-07-03

    Pseudomonas putida strain CSV86 metabolizes variety of aromatic compounds as the sole carbon source. Genome analysis revealed the presence of genes encoding putative transporters for benzoate, p-hydroxybenzoate, phenylacetate, p-hydroxyphenylacetate and vanillate. Bioinformatic analysis revealed that benzoate transport and metabolism genes are clustered at the ben locus as benK-catA-benE-benF. Protein topology prediction suggests that BenK (aromatic acid-H+ symporter of major facilitator superfamily) has 12 transmembrane α-helices with the conserved motif LADRXGRKX in loop 2, while BenE (benzoate-H+ symporter protein) has 11 predicted transmembrane α-helices. benF and catA encode benzoate specific porin, OprD and catechol 1,2-dioxygenase, respectively. Biochemical studies suggest that benzoate was transported by an inducible and active process. Inhibition (90%-100%) in the presence of dinitrophenol suggests that the energy for the transport process is derived from the proton motive force. The maximum rate of benzoate transport was 484 pmole min-1 mg-1 cells with an affinity constant, Kmof 4.5 μM. Transcriptional analysis of the benzoate and glucose-grown cells showed inducible expression of benF, benK and benE, suggesting that besides outer membrane porin, both inner membrane transporters probably contribute for the benzoate transport in P. putida strain CSV86. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. The metabolism of thymol by a Pseudomonas

    Science.gov (United States)

    Chamberlain, Enid M.; Dagley, S.

    1968-01-01

    1. Pseudomonas putida when grown with thymol contained a meta-fission dioxygenase, which required ferrous ions and readily cleaved the benzene nucleus of catechols between adjacent carbon atoms bearing hydroxyl and isopropyl groups. 2. 3-Hydroxythymo-1,4-quinone was excreted towards the end of exponential growth and later was slowly metabolized. This compound was oxidized by partially purified extracts only when NADH was supplied; the substrate for the dioxygenase appeared to be 3-hydroxythymo-1,4-quinol, which was readily and non-enzymically oxidized to the quinone. 3. 2-Oxobutyrate (0·9 mole) was formed from 1 mole of 3-hydroxythymo-1,4-quinone with the consumption of 1 mole of oxygen; acetate, isobutyrate and 2-hydroxybutyrate (which arose from the enzymic reduction of 2-oxobutyrate) were also formed. 4. These products, which were produced only when the catechol substrate contained a third hydroxyl group, appeared to result from the enzymic hydrolysis of the ring-fission product. PMID:4303067

  1. Scaling of triple differential cross-sections for asymmetric (e,2e ...

    Indian Academy of Sciences (India)

    Asymmetric (e, 2e) process; triple differential cross-section; scaling; helium ... initial state wave function is not exactly known and those in use do not have an ... Z dependence of the target wave function for (e, 2e) process. Consider the one- parameter variational wave function of helium ground state φi ( r1, r2) = (. Z 3 π ).

  2. Nr2e1 Deficiency Augments Palmitate-Induced Oxidative Stress in Beta Cells

    Directory of Open Access Journals (Sweden)

    Xiaoli Shi

    2016-01-01

    Full Text Available Nuclear receptor subfamily 2 group E member 1 (Nr2e1 has been regarded as an essential regulator of the growth of neural stem cells. However, its function elsewhere is unknown. In the present study, we generated Nr2e1 knockdown MIN6 cells and studied whether Nr2e1 knockdown affected basal beta cell functions such as proliferation, cell death, and insulin secretion. We showed that knockdown of Nr2e1 in MIN6 cells resulted in increased sensitivity to lipotoxicity, decreased proliferation, a partial G0/G1 cell-cycle arrest, and higher rates of apoptosis. Moreover, Nr2e1 deficiency exaggerates palmitate-induced impairment in insulin secretion. At the molecular level, Nr2e1 deficiency augments palmitate-induced oxidative stress. Nr2e1 deficiency also resulted in decreases in antioxidant enzymes and expression level of Nrf2. Together, this study indicated a potential protective effect of Nr2e1 on beta cells, which may serve as a target for the development of novel therapies for diabetes.

  3. Morbidly Obese Patients Exhibit Increased CYP2E1-Mediated Oxidation of Acetaminophen

    NARCIS (Netherlands)

    A. van Rongen (Anne); P.A.J. Välitalo (Pyry A. J.); M.Y. Peeters (Mariska); D. Boerma (Djamila); F.W. Huisman (Fokko W.); B. van Ramshorst (Bert); E.H.P.A. van Dongen (Eric); J.N. van den Anker (John); C.A.J. Knibbe (Catherijne)

    2016-01-01

    textabstractIntroduction: Acetaminophen (paracetamol) is mainly metabolized via glucuronidation and sulphation, while the minor pathway through cytochrome P450 (CYP) 2E1 is held responsible for hepatotoxicity. In obese patients, CYP2E1 activity is reported to be induced, thereby potentially

  4. Morbidly Obese Patients Exhibit Increased CYP2E1-Mediated Oxidation of Acetaminophen.

    NARCIS (Netherlands)

    Rongen, van A.; Välitalo, P.A.J.; Peeters, M.Y.; Boerma, D.; Huisman, F.W.; Ramshorst, van B.; Dongen, van E.P.; Anker, van den J.N.; Knibbe, C.A.J.

    2016-01-01

    INTRODUCTION Acetaminophen (paracetamol) is mainly metabolized via glucuronidation and sulphation, while the minor pathway through cytochrome P450 (CYP) 2E1 is held responsible for hepatotoxicity. In obese patients, CYP2E1 activity is reported to be induced, thereby potentially worsening the safety

  5. Spatial Localization of A2E in the Retinal Pigment Epithelium

    OpenAIRE

    Grey, Angus C.; Crouch, Rosalie K.; Koutalos, Yiannis; Schey, Kevin L.; Ablonczy, Zsolt

    2011-01-01

    The spatial distribution of A2E across the murine retinal pigment epithelium was determined using matrix-assisted laser desorption-ionization imaging mass spectrometry. This is the first technique to allow mapping of specific lipofuscin components in native retinal pigment epithelium tissue with high spatial resolution and to allow spatial correlation of lipofuscin fluorescence with A2E distribution.

  6. 77 FR 42677 - Special Conditions: General Electric CT7-2E1 Turboshaft Engine

    Science.gov (United States)

    2012-07-20

    ... Federal Aviation Administration 14 CFR Part 33 Special Conditions: General Electric CT7-2E1 Turboshaft Engine AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed special conditions. SUMMARY: This action proposes special conditions for the General Electric CT7-2E1 engine model. This...

  7. Increased immunogenicity and protective efficacy of influenza M2e fused to a tetramerizing protein

    DEFF Research Database (Denmark)

    Andersson, Anne-Marie Carola; Håkansson, Kjell Ove; Jensen, Benjamin Anderschou Holbech

    2012-01-01

    The ectodomain of the matrix 2 protein (M2e) of influenza A virus represents an attractive target for developing a universal influenza A vaccine, with its sequence being highly conserved amongst human variants of this virus. With the aim of targeting conformational epitopes presumably shared...... by diverse influenza A viruses, a vaccine (M2e-NSP4) was constructed linking M2e (in its consensus sequence) to the rotavirus fragment NSP4(98-135); due to its coiled-coil region this fragment is known to form tetramers in aqueous solution and in this manner we hoped to mimick the natural configuration of M2...... reactive antibody response than does M2e peptide as measured in two different assays. Most importantly, vaccination with M2e-NSP4 caused a significant decrease in lung virus load early after challenge with influenza A virus and maintained its efficacy against a lethal challenge even at very low vaccine...

  8. Degradation of polynuclear aromatic hydrocarbons by two strains of Pseudomonas

    Directory of Open Access Journals (Sweden)

    Obinna C. Nwinyi

    Full Text Available ABSTRACT The goal of this investigation was to isolate competent polynuclear aromatic hydrocarbons degraders that can utilize polynuclear aromatic hydrocarbons of former industrial sites at McDoel Switchyard in Bloomington, Indiana. Using conventional enrichment method based on soil slurry, we isolated, screened and purified two bacterial species strains PB1 and PB2. Applying the ribotyping technique using the 16S rRNA gene analysis, the strains were assigned to the genus Pseudomonas (Pseudomonas plecoglossicida strain PB1 and Pseudomonas sp. PB2. Both isolates showed promising metabolic capacity on pyrene sprayed MS agar plates during the preliminary investigations. Using time course studies in the liquid cultures at calculated concentrations 123, 64, 97 and 94 ppm for naphthalene, chrysene, fluroanthene and pyrene, P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 showed partial utilization of the polynuclear aromatic hydrocarbons. Naphthalene was degraded between 26% and 40%, chrysene 14% and 16%, fluroanthene 5% and 7%; pyrene 8% and 13% by P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 respectively. Based on their growth profile, we developed a model R2 = 1 to predict the degradation rate of slow polynuclear aromatic hydrocarbon-degraders where all the necessary parameters are constant. From this investigation, we confirm that the former industrial site soil microbial communities may be explored for the biorestoration of the industrial site.

  9. Pseudomonas fluorescens' view of the periodic table.

    Science.gov (United States)

    Workentine, Matthew L; Harrison, Joe J; Stenroos, Pernilla U; Ceri, Howard; Turner, Raymond J

    2008-01-01

    Growth in a biofilm modulates microbial metal susceptibility, sometimes increasing the ability of microorganisms to withstand toxic metal species by several orders of magnitude. In this study, a high-throughput metal toxicity screen was initiated with the aim of correlating biological toxicity data in planktonic and biofilm cells to the physiochemical properties of metal ions. To this end, Pseudomonas fluorescens ATCC 13525 was grown in the Calgary Biofilm Device (CBD) and biofilms and planktonic cells of this microorganism were exposed to gradient arrays of different metal ions. These arrays included 44 different metals with representative compounds that spanned every group of the periodic table (except for the halogens and noble gases). The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum biofilm eradication concentration (MBEC) values were obtained after exposing the biofilms to metal ions for 4 h. Using these values, metal ion toxicity was correlated to the following ion-specific physicochemical parameters: standard reduction-oxidation potential, electronegativity, the solubility product of the corresponding metal-sulfide complex, the Pearson softness index, electron density and the covalent index. When the ions were grouped according to outer shell electron structure, we found that heavy metal ions gave the strongest correlations to these parameters and were more toxic on average than the other classes of the ions. Correlations were different for biofilms than for planktonic cells, indicating that chemical mechanisms of metal ion toxicity differ between the two modes of growth. We suggest that biofilms can specifically counter the toxic effects of certain physicochemical parameters, which may contribute to the increased ability of biofilms to withstand metal toxicity.

  10. Aflatoxin B₁ degradation by a Pseudomonas strain.

    Science.gov (United States)

    Sangare, Lancine; Zhao, Yueju; Folly, Yawa Minnie Elodie; Chang, Jinghua; Li, Jinhan; Selvaraj, Jonathan Nimal; Xing, Fuguo; Zhou, Lu; Wang, Yan; Liu, Yang

    2014-10-23

    Aflatoxin B1 (AFB1), one of the most potent naturally occurring mutagens and carcinogens, causes significant threats to the food industry and animal production. In this study, 25 bacteria isolates were collected from grain kernels and soils displaying AFB1 reduction activity. Based on its degradation effectiveness, isolate N17-1 was selected for further characterization and identified as Pseudomonas aeruginosa. P. aeruginosa N17-1 could degrade AFB₁, AFB₂ and AFM₁ by 82.8%, 46.8% and 31.9% after incubation in Nutrient Broth (NB) medium at 37 °C for 72 h, respectively. The culture supernatant of isolate N17-1 degraded AFB₁ effectively, whereas the viable cells and intra cell extracts were far less effective. Factors influencing AFB1 degradation by the culture supernatant were investigated. Maximum degradation was observed at 55 °C. Ions Mn²⁺ and Cu²⁺ were activators for AFB1 degradation, however, ions Mg²⁺, Li⁺, Zn²⁺, Se²⁺, Fe³⁺ were strong inhibitors. Treatments with proteinase K and proteinase K plus SDS significantly reduced the degradation activity of the culture supernatant. No degradation products were observed based on preliminary LC-QTOF/MS analysis, indicating AFB₁ was metabolized to degradation products with chemical properties different from that of AFB₁. The results indicated that the degradation of AFB₁ by P. aeruginosa N17-1 was enzymatic and could have a great potential in industrial applications. This is the first report indicating that the isolate of P. aeruginosa possesses the ability to degrade aflatoxin.

  11. Engineering Pseudomonas stutzeri as a biogeochemical biosensor

    Science.gov (United States)

    Boynton, L.; Cheng, H. Y.; Del Valle, I.; Masiello, C. A.; Silberg, J. J.

    2016-12-01

    Biogeochemical cycles are being drastically altered as a result of anthropogenic activities, such as the burning of fossil fuels and the industrial production of ammonia. We know microbes play a major part in these cycles, but the extent of their biogeochemical roles remains largely uncharacterized due to inadequacies with culturing and measurement. While metagenomics and other -omics methods offer ways to reconstruct microbial communities, these approaches can only give an indication of the functional roles of microbes in a community. These -omics approaches are rapidly being expanded to the point of outpacing our knowledge of functional genes, which highlights an inherent need for analytical methods that non-invasively monitor Earth's processes in real time. Here we aim to exploit synthetic biology methods in order to engineer a ubiquitous denitrifying microbe, Pseudomonas stutzeri that can act as a biosensor in soil and marine environments. By using an easily cultivated microbe that is also common in many environments, we hope to develop a tool that allows us to zoom in on specific aspects of the nitrogen cycle. In order to monitor processes occurring at the genetic level in environments that cannot be resolved with fluorescence-based methods, such as soils, we have developed a system that instead relies on gas production by engineered microbial biosensors. P. stutzeri has been successfully engineered to release a gas, methyl bromide, which can continuously and non-invasively be measured by GC-MS. Similar to using Green Fluorescent Protein, GFP, in the biological sciences, the gene controlling gas production can be linked to those involved in denitrification, thereby creating a quantifiable gas signal that is correlated with microbial activity in the soil. Synthetically engineered microbial biosensors could reveal key aspects of metabolism in soil systems and offer a tool for characterizing the scope and degree of microbial impact on major biogeochemical cycles.

  12. Therapy of Pseudomonas aeruginosa infections with tobramycin.

    Science.gov (United States)

    Blair, D C; Fekety, F R; Bruce, B; Silva, J; Archer, G

    1975-07-01

    The efficacy of tobramycin in doses of 2.7 to 5.6 mg/kg per day in 29 courses of therapy in 25 hospitalized patients with serious Pseudomonas aeruginosa infections was studied. Eighty-three percent of the P. aeruginosa strains showed zones of inhibition of 16 mm or more around a 10-mug tobramycin disk in the Bauer-Kirby disk method. Tobramycin minimal inhibitory concentration ranged from <0.05 to 1.5 mug/ml (microtiter twofold dilution method); for gentamicin they ranged from 0.05 to 6.2 mug/ml; corresponding geometric means were 0.19 and 0.49 mug/ml. Therapy was given for a median of 10 days (mean 19, range 1 to 83). The clinically satisfactory response rate for the 29 courses of therapy was 52%: critically ill, 44%; seriously ill, 50%; moderately ill, 80%. The response rates for various sites of infection were bone and cartilage, 100%; urinary tract infection, 56%; wound, 50%; respiratory tract, 67%; septicemia, 40%; abscess, 0%; burns, 44%. No adverse reactions were seen. Serum concentration (mug/ml +/- standard deviation) of tobramycin determined by an agar-well plate method, were 4.81 +/- 2.17 (1 h); 3.24 +/- 1.43 (2 h); 2.35 +/- 1.30 (4 h); and 1.40 +/- 1.09 (8 h). Tobramycin appears to be as effacacious as gentamicin in the treatment of serious P. aeruginosa infections and has a theoretical advantage of lower minimal inhibitory concentration for P. aeruginosa. The data suggest that, for life-threatening infections, dosages of tobramycin may need to be increased over those used in this study.

  13. Ambroxol interferes with Pseudomonas aeruginosa quorum sensing.

    Science.gov (United States)

    Lu, Qi; Yu, Jialin; Yang, Xiqiang; Wang, Jiarong; Wang, Lijia; Lin, Yayin; Lin, Lihua

    2010-09-01

    The mucolytic agent ambroxol has been reported to interfere with the formation of Pseudomonas aeruginosa-derived biofilms in addition to reducing alginate production by undefined mechanisms. Since quorum sensing is a key regulator of virulence and biofilm formation, we examined the effects of ambroxol on P. aeruginosa PAO1 wild-type bacterial clearance rates, adhesion profiles and biofilm formation compared with the quorum sensing-deficient, double-mutant strains DeltalasR DeltarhlR and DeltalasI DeltarhlI. Data presented in this report demonstrated that ambroxol treatment reduced survival rates of the double-mutant strains compared with the wild-type strain in a dose-dependent manner even though the double-mutants had increased adhesion in the presence of ambroxol compared with the wild-type strain. The PAO1 wild-type strain produced a significantly thicker biofilm (21.64+/-0.57 microm) compared with the biofilms produced by the DeltalasR DeltarhlR (7.36+/-0.2 microm) and DeltalasI DeltarhlI (6.62+/-0.31 microm) isolates. Ambroxol treatment reduced biofilm thickness, increased areal porosity, and decreased the average diffusion distance and textual entropy of wild-type and double-mutant strains. However, compared with the double-mutant strains, the changes observed for the wild-type strain were more clearly defined. Finally, ambroxol exhibited significant antagonistic quorum-sensing properties, suggesting that it could be adapted for use clinically in the treatment of cystic fibrosis and to reduce biofilm formation and in the colonisation of indwelling devices. Copyright (c) 2010 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  14. Chromosomal organization and segregation in Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Isabelle Vallet-Gely

    2013-05-01

    Full Text Available The study of chromosomal organization and segregation in a handful of bacteria has revealed surprising variety in the mechanisms mediating such fundamental processes. In this study, we further emphasized this diversity by revealing an original organization of the Pseudomonas aeruginosa chromosome. We analyzed the localization of 20 chromosomal markers and several components of the replication machinery in this important opportunistic γ-proteobacteria pathogen. This technique allowed us to show that the 6.3 Mb unique circular chromosome of P. aeruginosa is globally oriented from the old pole of the cell to the division plane/new pole along the oriC-dif axis. The replication machinery is positioned at mid-cell, and the chromosomal loci from oriC to dif are moved sequentially to mid-cell prior to replication. The two chromosomal copies are subsequently segregated at their final subcellular destination in the two halves of the cell. We identified two regions in which markers localize at similar positions, suggesting a bias in the distribution of chromosomal regions in the cell. The first region encompasses 1.4 Mb surrounding oriC, where loci are positioned around the 0.2/0.8 relative cell length upon segregation. The second region contains at least 800 kb surrounding dif, where loci show an extensive colocalization step following replication. We also showed that disrupting the ParABS system is very detrimental in P. aeruginosa. Possible mechanisms responsible for the coordinated chromosomal segregation process and for the presence of large distinctive regions are discussed.

  15. Pathological aggression in "fierce" mice corrected by human nuclear receptor 2E1.

    Science.gov (United States)

    Abrahams, Brett S; Kwok, Melvin C H; Trinh, Eric; Budaghzadeh, Saeed; Hossain, Sazzad M; Simpson, Elizabeth M

    2005-07-06

    "Fierce" mice, homozygous for the deletion of nuclear receptor 2E1 (NR2E1), show abnormal brain-eye development and pathological aggression. To evaluate functional equivalency between mouse and human NR2E1, we generated mice transgenic for a genomic clone spanning the human NR2E1 locus and bred these animals to fierce mice deleted for the corresponding mouse gene. In fierce mutants carrying human NR2E1, structural brain defects were eliminated and eye abnormalities ameliorated. Excitingly, behavior in these "rescue" mice was indistinguishable from controls. Because no artificial promoter was used to drive transgene expression, promoter and regulatory elements within the human NR2E1 clone are functional in mouse. Normal behavior in rescue animals suggests that mechanisms underlying the behavioral abnormalities in fierce mice may also be conserved in humans. Our data support the hypothesis that variation at NR2E1 may contribute to human behavioral disorders. Use of this rescue paradigm with other genes will permit the direct evaluation of human genes hypothesized to play a causal role in psychiatric disease but for which evidence is lacking or equivocal.

  16. Risk assessment of Pseudomonas aeruginosa in water.

    Science.gov (United States)

    Mena, Kristina D; Gerba, Charles P

    2009-01-01

    drinking water industry, very little has been reported regarding the role of P. aeruginosa in biofilms. Tap water appears to be a significant route of transmission in hospitals, from colonization of plumbing fixtures. It is still not clear if the colonization results from the water in the distribution system, or personnel use within the hospital. Infections and colonization can be significantly reduced by placement of filters on the water taps. The oral dose of P. aeruginosa required to establish colonization in a healthy subject is high (George et al. 1989a). During dose-response studies, even when subjects (mice or humans) were colonized via ingestion, there was no evidence of disease. P. aeruginosa administered by the aerosol route at levels of 10(7) cells did cause disease symptoms in mice, and was lethal in aerosolized doses of 10(9) cells. Aerosol dose-response studies have not been undertaken with human subjects. Human health risks associated with exposure to P. aeruginosa via drinking water ingestion were estimated using a four-step risk assessment approach. The risk of colonization from ingesting P. aeruginosa in drinking water is low. The risk is slightly higher if the subject is taking an antibiotic resisted by P. aeruginosa. The fact that individuals on ampicillin are more susceptible to Pseudomonas gastrointestinal infection probably results from suppression of normal intestinal flora, which would allow Pseudomonas to colonize. The process of estimating risk was significantly constrained because of the absence of specific (quantitative) occurrence data for Pseudomonas. Sensitivity analysis shows that the greatest source of variability/uncertainty in the risk assessment is from the density distribution in the exposure rather than the dose-response or water consumption distributions. In summary, two routes appear to carry the greatest health risks from contacting water contaminated with P. aeruginosa (1) skin exposure in hot tubs and (2) lung exposure from

  17. Role of CYP2E1 genotypes in susceptibility to colorectal cancer in the Kashmiri population

    Directory of Open Access Journals (Sweden)

    Sameer A

    2011-10-01

    Full Text Available Abstract Cytochrome P450 2E1 (CYP2E1 is a key enzyme involved in the metabolic activation of procarcinogens such as N-nitrosoamines and low-molecular-weight organic compounds. The main aim of this study was to determine whether CYP450 2E1 polymorphisms are associated with the risk of colorectal cancer (CRC. We investigated the genotype distribution of the CYP2E1 gene RsaI and a 96-base pair (bp insertion in 86 CRC cases in comparison with 160 healthy subjects. We found the frequency of the CYP2E1 RsaI genotype to be 53.5 per cent (46/86 for c1/c1, 17.4 per cent (15/86 for c1/c2 and 29.1 per cent (25/86 for c2/c2, and the CYP2E1 98-bp insertion frequencies to be 63.9 per cent (55/86 for non-insertion (i/i, 22.1 per cent (19/86 for heterozygous insertion (i/I and 36.0 per cent (12/86 for homozygous insertion (I/I among CRC cases. We also found the CYP2E1 RsaI c2/c2 and CYP2E1 98-bp heterozygous i/I genotypes to be significantly associated with an increased risk of CRC (p = 0.01. We suggest that CYP2E1 polymorphisms are involved in the susceptibility to developing CRC in the ethnic Kashmiri population.

  18. Absence of NR2E1 mutations in patients with aniridia

    Science.gov (United States)

    Corso-Díaz, Ximena; Borrie, Adrienne E.; Bonaguro, Russell; Schuetz, Johanna M.; Rosenberg, Thomas; Jensen, Hanne; Brooks, Brian P.; MacDonald, Ian M.; Pasutto, Francesca; Walter, Michael A.; Grønskov, Karen; Brooks-Wilson, Angela

    2012-01-01

    Purpose Nuclear receptor 2E1 (NR2E1) is a transcription factor with many roles during eye development and thus may be responsible for the occurrence of certain congenital eye disorders in humans. To test this hypothesis, we screened NR2E1 for candidate mutations in patients with aniridia and other congenital ocular malformations (anterior segment dysgenesis, congenital optic nerve malformation, and microphthalmia). Methods The NR2E1 coding region, 5′ and 3′ untranslated regions (UTRs), exon flanking regions including consensus splice sites, and six evolutionarily conserved non-coding candidate regulatory regions were analyzed by sequencing 58 probands with aniridia of whom 42 were negative for PAX6 mutations. Nineteen probands with anterior segment dysgenesis, one proband with optic nerve malformation, and two probands with microphthalmia were also sequenced. The control population comprised 376 healthy individuals. All sequences were analyzed against the GenBank sequence AL078596.8 for NR2E1. In addition, the coding region and flanking intronic sequences of FOXE3, FOXC1, PITX2, CYP1B1, PAX6, and B3GALTL were sequenced in one patient and his relatives. Results Sequencing analysis showed 17 NR2E1 variants including two novel rare non-coding variants (g.-1507G>A, g.14258C>T), and one novel rare coding variant (p.Arg274Gly). The latter was present in a male diagnosed with Peters’ anomaly who subsequently was found to have a known causative mutation for Peters’ plus syndrome in B3GALTL (c.660+1G>A). In addition, the NR2E1 novel rare variant Arg274Gly was present in the unaffected mother of the patient but absent in 746 control chromosomes. Conclusions We eliminated a major role for NR2E1 regulatory and coding mutations in aniridia and found a novel rare coding variant in NR2E1. In addition, we found no coding region variation in the control population for NR2E1, which further supports its previously reported high level of conservation and low genetic diversity

  19. Uji produksi biosurfaktan oleh Pseudomonas sp. pada substrat yang berbeda

    Directory of Open Access Journals (Sweden)

    Fatimah Fatimah

    2012-02-01

    Full Text Available Biosurfactant, microbial metabolite whose properties like surfactant, was suggested to replace chemically synthesized surfactant for take in hand environtmental pollution by petroleum hydrocarbon. This work was done to examine potency of Pseudomonas sp. isolated from Tanjung Perak Harbor to produce biosurfactant. Also, to know the effect of different substrates (glucose + yeast extract, lubricating oil and hexadecane toward biosurfactant production. Pseudomonas sp. grown in mineral synthetic water and biosurfactant production was measured on stationary phase. Biosurfactant production based on emulsification activity and surface tension reduction of supernatant (using Du Nouy tensiometer. Solar, lubricating oil, and hexadecane were used to examine emulsification activity. Results indicated that Pseudomonas sp. have a potency to produce biosurfactant. Surface tension of supernatant decreased up to 20 dyne/cm, when grown on hexadecane substrate. Hexadecane is the best growing substrate for biosurfactant production than others.

  20. Intramolecular electron transfer in Pseudomonas aeruginosa cd(1) nitrite reductase

    DEFF Research Database (Denmark)

    Farver, Ole; Brunori, Maurizio; Cutruzzolà, Francesca

    2009-01-01

    The cd(1) nitrite reductases, which catalyze the reduction of nitrite to nitric oxide, are homodimers of 60 kDa subunits, each containing one heme-c and one heme-d(1). Heme-c is the electron entry site, whereas heme-d(1) constitutes the catalytic center. The 3D structure of Pseudomonas aeruginosa...... is controlling this internal ET step. In this study we have investigated the internal ET in the wild-type and His369Ala mutant of P. aeruginosa nitrite reductases and have observed similar cooperativity to that of the Pseudomonas stutzeri enzyme. Heme-c was initially reduced, in an essentially diffusion...... nitrite reductase has been determined in both fully oxidized and reduced states. Intramolecular electron transfer (ET), between c and d(1) hemes is an essential step in the catalytic cycle. In earlier studies of the Pseudomonas stutzeri enzyme, we observed that a marked negative cooperativity...

  1. Effects of ambroxol on alginate of mature Pseudomonas aeruginosa biofilms.

    Science.gov (United States)

    Li, Fang; Yu, Jialin; Yang, Hua; Wan, Zhenyan; Bai, Dan

    2008-07-01

    Biofilm-forming bacteria Pseudomonas aeruginosa is a common pathogen in mechanically ventilated newborns, which can cause life-threatening infections. Alginate of mucoid Pseudomonas aeruginosa biofilms is considered an important virulence factor which contributes to the resistance to antibiotics. Traditionally, ambroxol is widely used in newborns with lung problems as a mucolytic agent and antioxidant agent as well. And there are few studies that demonstrated the anti-biofilm activity of ambroxol. In this study, we found that ambroxol can affect the structure of mucoid Pseudomonas aeruginosa biofilms. Further, we found that ambroxol reduces the production of alginate, the expression of the important genes and the activity of key enzyme guanosine diphospho-D-mannose dehydrogenase (GDP-mannose dehydrogenase; GMD) which were involved in alginate biosynthesis.

  2. Experimental Pseudomonas aeruginosa mediated rhino sinusitis in mink

    DEFF Research Database (Denmark)

    Kirkeby, S.; Hammer, A. S.; Høiby, N.

    2017-01-01

    The nasal and sinus cavities in children may serve as reservoirs for microorganisms that cause recurrent and chronic lung infections. This study evaluates whether the mink can be used as an animal model for studying Pseudomonas aeruginosa mediated rhino-sinusitis since there is no suitable...... in the infected mink shows features of carbohydrate expression comparable to what has been described in the respiratory system after Pseudomonas aeruginosa infection in humans. It is suggested that the mink is suitable for studying Pseudomonas aeruginosa mediated rhino-sinusitis....... traditional animal model for this disease. Nasal tissue samples from infected and control mink were fixed in formalin, demineralized, and embedded in paraffin. A histological examination of sections from the infected animals revealed disintegration of the respiratory epithelium lining the nasal turbinates...

  3. Conservation of the response regulator gene gacA in Pseudomonas species

    NARCIS (Netherlands)

    Souza, J.T.; Mazzola, M.; Raaijmakers, J.M.

    2003-01-01

    The response regulator gene gacA influences the production of several secondary metabolites in both pathogenic and beneficial Pseudomonas spp. In this study, we developed primers and a probe for the gacA gene of Pseudomonas species and sequenced a 425 bp fragment of gacA from ten Pseudomonas strains

  4. Data of evolutionary structure change: 1YDVA-1AW2E [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1YDVA-1AW2E 1YDV 1AW2 A E RKYFVAANWKCNGTLESIKSLTNSFNNLDFDPSKLDVVV...--- RHPVVMGNWKLNGSKEMVVDLLNGLNAELEGVTGVDVAVAPPALFVDLAERTLTEAGSAIILGA...fEVID> 0 1YDV A 1YDVA...e> ALA CA 311 1YDV A 1YDVA

  5. Drones of the dwarf honey bee Apis florea are attracted to (2E)-9-oxodecenoic acid and (2E)-10-hydroxydecenoic acid.

    Science.gov (United States)

    Nagaraja, Narayanappa; Brockmann, Axel

    2009-06-01

    The queen mandibular gland component (2E)-9-oxodecenoic acid (9-ODA) has been suggested to function as the major sex pheromone component in all honey bee species. In contrast to this hypothesis, chemical analyses showed that in the Asian dwarf honey bee species, Apis florea, a different decenoic acid, (2E)-10-hydroxydecenoic acid (10-HDA), is the major component in the mandibular gland secretion. We show here that A. florea drones are attracted to 9-ODA as well as to 10-HDA. However, 10-HDA attracted higher numbers of drones at lower dosages than 9-ODA, and also was more attractive when directly compared to 9-ODA in a dual attraction experiment. We conclude that 10-HDA has to be viewed as the major sex pheromone in A. florea. The result that both pheromone components are capable of attracting drones when presented alone was unexpected with regard to existing sex pheromone attraction experiments in honey bees.

  6. A novel M2e based flu vaccine formulation for dogs.

    Directory of Open Access Journals (Sweden)

    Denis Leclerc

    Full Text Available BACKGROUND: The USA 2004 influenza virus outbreak H3N8 in dogs heralded the emergence of a new disease in this species. A new inactivated H3N8 vaccine was developed to control the spread of the disease but, as in humans and swine, it is anticipated that the virus will mutate shift and drift in the dog population. Therefore, there is a need for a vaccine that can trigger a broad protection to prevent the spread of the virus and the emergence of new strains. METHODOLOGY AND PRINCIPAL FINDINGS: The universal M2e peptide is identical in almost all the H3N8 influenza strains sequenced to date and known to infect dogs. This epitope is therefore a good choice for development of a vaccine to provide broad protection. Malva mosaic virus (MaMV nanoparticles were chosen as a vaccine platform to improve the stability of the M2e peptide and increase its immunogenicity in animals. The addition of an adjuvant (OmpC purified from Salmonella typhi membrane in the vaccine formulation increased the immune response directed to the M2e peptide significantly and enlarged the protection to include the heterosubtypic strain of influenza in a mouse model. An optimal vaccine formulation was also shown to be immunogenic in dogs. CONCLUSIONS AND SIGNIFICANCE: The MaMV vaccine platform triggered an improved immune response directed towards the universal M2e peptide. The adjuvant OmpC increased the immune response to the M2e peptide and protection to a heterosubtypic influenza strain that harbors a different M2e peptide in a mouse model. Antibodies generated by the vaccine formulation showed cross-reactivity with M2e peptides derived from influenza strains H9N2, H5N1 and H1N1. The vaccine formulation shows a potential for commercialization of a new M2e based vaccine in dogs.

  7. New coplanar (e,2e) experiments for the ionisation of He and Ar atoms

    Energy Technology Data Exchange (ETDEWEB)

    Casagrande, E.M. Staicu [Laboratoire des Collisions Atomiques et Moleculaires (UMR 8625) and Federation Lumiere Matiere (FR 2764), Bat. 351, Universite de Paris-Sud XI, 91405 Orsay Cedex (France)], E-mail: staicu-casagrande@lcam.u-psud.fr; Catoire, F.; Naja, A.; Ren, X.G.; Lahmam-Bennani, A. [Laboratoire des Collisions Atomiques et Moleculaires (UMR 8625) and Federation Lumiere Matiere (FR 2764), Bat. 351, Universite de Paris-Sud XI, 91405 Orsay Cedex (France); Nekkab, M. [Laboratoire de Physique Quantique et Systemes Dynamiques, Universite Ferhat Abbas, Setif (Algeria); Dal Cappello, C. [Laboratoire de Physique Moleculaire et des Collisions and ICPMB (FR 2843), Universite Paul Verlaine-Metz, Institut de Physique, 1 rue Arago, 57078 Metz Cedex 3 (France); Bartschat, K. [Department of Physics and Astronomy, Drake University, Des Moines, IA 5031 (United States); Whelan, C.T. [Department of Physics, College of Sciences, Norfolk, VA 23529-0116 (United States)

    2007-10-15

    We report new coplanar measurements of the (e,2e) TDCS for the ionisation of helium 1s-shell and argon 3p- and 2p-shells. The kinematics employed remained rather unexplored to date, and could be investigated here using an improved version of our multi-angle (e,2e) spectrometer, with increased sensitivity. The results are discussed in the light of state-of-the-art theoretical models.

  8. Immunochemical recognition of A2E, a pigment in the lipofuscin of retinal pigment epithelial cells

    OpenAIRE

    Abeywickrama, Chandima; Matsuda, Hiroko; Jockusch, Steffen; Zhou, Jilin; Jang, Young P.; Chen, Bi-Xing; Itagaki, Yasuhiro; Erlanger, Bernard F.; NAKANISHI, Koji"; Turro, Nicholas J.; Sparrow, Janet R

    2007-01-01

    The autofluorescent lipofuscin pigment A2E accumulates in retinal pigment epithelial cells with age and is particularly abundant in some retinal disorders. To generate a polyclonal antibody that recognizes this pyridinium bisretinoid molecule, we immunized rabbits with bovine serum albumin (BSA) conjugates in which the protein was linked to the A2E molecule via its pyridinium ethanolamine moiety. Analysis by matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI-T...

  9. Information Management of Genome Enabled Data Streams for Pseudomonas syringae on the Pseudomonas-Plant Interaction (PPI Website

    Directory of Open Access Journals (Sweden)

    Magdalen Lindeberg

    2011-11-01

    Full Text Available Genome enabled research has led to a large and ever-growing body of data on Pseudomonas syringae genome variation and characteristics, though systematic capture of this information to maximize access by the research community remains a significant challenge. Major P. syringae data streams include genome sequence data, newly identified type III effectors, biological characterization data for type III effectors, and regulatory feature characterization. To maximize data access, the Pseudomonas-Plant Interaction (PPI website [1] is primarily focused on categorization of type III effectors and curation of effector functional data represented in the Hop database and Pseudomonas-Plant Interaction Resource, respectively. The PPI website further serves as a conduit for incorporation of new genome characterization data into the annotation records at NCBI and other data repositories, and clearinghouse for additional data sets and updates in response to the evolving needs of the research community.

  10. Type VI Secretion System in Pseudomonas aeruginosa

    Science.gov (United States)

    Hachani, Abderrahman; Lossi, Nadine S.; Hamilton, Alexander; Jones, Cerith; Bleves, Sophie; Albesa-Jové, David; Filloux, Alain

    2011-01-01

    Pseudomonas aeruginosa is a Gram-negative bacterium causing chronic infections in cystic fibrosis patients. Such infections are associated with an active type VI secretion system (T6SS), which consists of about 15 conserved components, including the AAA+ ATPase, ClpV. The T6SS secretes two categories of proteins, VgrG and Hcp. Hcp is structurally similar to a phage tail tube component, whereas VgrG proteins show similarity to the puncturing device at the tip of the phage tube. In P. aeruginosa, three T6SSs are known. The expression of H1-T6SS genes is controlled by the RetS sensor. Here, 10 vgrG genes were identified in the PAO1 genome, among which three are co-regulated with H1-T6SS, namely vgrG1a/b/c. Whereas VgrG1a and VgrG1c were secreted in a ClpV1-dependent manner, secretion of VgrG1b was ClpV1-independent. We show that VgrG1a and VgrG1c form multimers, which confirmed the VgrG model predicting trimers similar to the tail spike. We demonstrate that Hcp1 secretion requires either VgrG1a or VgrG1c, which may act independently to puncture the bacterial envelope and give Hcp1 access to the surface. VgrG1b is not required for Hcp1 secretion. Thus, VgrG1b does not require H1-T6SS for secretion nor does H1-T6SS require VgrG1b for its function. Finally, we show that VgrG proteins are required for secretion of a genuine H1-T6SS substrate, Tse3. Our results demonstrate that VgrG proteins are not only secreted components but are essential for secretion of other T6SS substrates. Overall, we emphasize variability in behavior of three P. aeruginosa VgrGs, suggesting that, although very similar, distinct VgrGs achieve specific functions. PMID:21325275

  11. Gene expression in Pseudomonas aeruginosa swarming motility

    Directory of Open Access Journals (Sweden)

    Déziel Eric

    2010-10-01

    Full Text Available Abstract Background The bacterium Pseudomonas aeruginosa is capable of three types of motilities: swimming, twitching and swarming. The latter is characterized by a fast and coordinated group movement over a semi-solid surface resulting from intercellular interactions and morphological differentiation. A striking feature of swarming motility is the complex fractal-like patterns displayed by migrating bacteria while they move away from their inoculation point. This type of group behaviour is still poorly understood and its characterization provides important information on bacterial structured communities such as biofilms. Using GeneChip® Affymetrix microarrays, we obtained the transcriptomic profiles of both bacterial populations located at the tip of migrating tendrils and swarm center of swarming colonies and compared these profiles to that of a bacterial control population grown on the same media but solidified to not allow swarming motility. Results Microarray raw data were corrected for background noise with the RMA algorithm and quantile normalized. Differentially expressed genes between the three conditions were selected using a threshold of 1.5 log2-fold, which gave a total of 378 selected genes (6.3% of the predicted open reading frames of strain PA14. Major shifts in gene expression patterns are observed in each growth conditions, highlighting the presence of distinct bacterial subpopulations within a swarming colony (tendril tips vs. swarm center. Unexpectedly, microarrays expression data reveal that a minority of genes are up-regulated in tendril tip populations. Among them, we found energy metabolism, ribosomal protein and transport of small molecules related genes. On the other hand, many well-known virulence factors genes were globally repressed in tendril tip cells. Swarm center cells are distinct and appear to be under oxidative and copper stress responses. Conclusions Results reported in this study show that, as opposed to

  12. Polymorphism of gene UBE2E2 and the risk of developing diabetes type 2

    Directory of Open Access Journals (Sweden)

    Elena Vladimirovna Kazakova

    2015-07-01

    Full Text Available Recently, the ubiquitin–proteasome pathway has emerged as a crucial pathway for protein turnover, and it has also been identified as an important factor for insulin synthesis. This pathway plays a critical role inside β cells; therefore, it has naturally been linked with various insulin-related diseases, most notably type 2 diabetes mellitus (T2DM, but also other metabolic diseases and symptoms such as obesity and atherosclerotic plaques. The UBE2E2 gene encodes ubiquitin-conjugating enzyme E2 E2 (UBE2E2, which plays an important role in the synthesis and secretion of insulin. UBE2E2  is a protein expressed in the pancreas, liver, and adipose tissue, as well as in an insulin-secreting cell line . The results of some studies have indicated that single nucleotide polymorphisms on UBE2E2 (rs6780569, rs7612463, rs9812056 are associated with T2DM risk in Japanese, Korean and Chinese populations. Therefore, the UBE2E2 gene has started to draw interest from researchers because of its newly discovered relationships with various diseases.

  13. TFAP2E hypermethylation was associated with survival advantage in patients with colorectal cancer.

    Science.gov (United States)

    Zhang, Zuo-Ming; Wang, Yibaina; Huang, Rong; Liu, Yu-Peng; Li, Xia; Hu, Fu-Lan; Zhu, Lin; Wang, Fan; Cui, Bin-Bin; Dong, Xin-Shu; Zhao, Ya-Shuang

    2014-12-01

    Hypermethylation of TFAP2E (AP-2E) is associated with the chemotherapy-resistant in patients with colorectal cancer (CRC), but its implications on prognosis directly remain unknown. This study was aimed to investigate the role of AP-2E methylation status and other clinicopathologic parameters as predictors of prognosis. We detected the methylation status of AP-2E in tumor and adjacent non-tumor tissues from 311 sporadic CRC patients by methylation-sensitive high-resolution melting analysis. Log-rank tests and multivariate Cox analyses were performed to evaluate the role of AP-2E methylation status and other clinicopathologic parameters as predictors of prognosis. Hypermethylation of AP-2E was detected in 61 % (190/311) tumor tissues. It occurred more frequently in tumors in earlier stages (I/II; P = 0.02), lower levels of tumor invasion (T1-T3; P = 0.04), fewer lymph nodes involved (N0; P ratio of 0.486 (95 % CI 0.342-0.692, P advantage in patients with CRC.

  14. Catalytic activity and quantitation of cytochrome P-450 2E1 in prenatal human brain.

    Science.gov (United States)

    Brzezinski, M R; Boutelet-Bochan, H; Person, R E; Fantel, A G; Juchau, M R

    1999-06-01

    Cytochrome P-450 2E1 (CYP2E1) is a readily inducible hemoprotein that catalyzes the oxidation of endogenous compounds and many low molecular weight xenobiotics. As the major component of the microsomal ethanol oxidizing system, it contributes significantly to ethanol metabolism and the formation of the highly reactive metabolite acetaldehyde. The leaky property of this enzyme results in the generation of reactive oxygen species that can induce oxidative stress and cytotoxic conditions deleterious to development. To further investigate the proposed role of CYP2E1 in the etiology of alcohol teratogenesis, the current study focused on the quantification of CYP2E1 in prenatal human brain, a tissue that is highly vulnerable to the damaging effects of ethanol throughout gestation. In microsomal samples prepared from pools of brain tissues, immunoreactive protein was detected by Western blot analysis using enhanced chemiluminescence, whereas functional protein was estimated with an enzymatic assay using p-nitrophenol and an electrochemical detection system. CYP2E1 transcript was consistently detected in RNA samples prepared from individual brain tissues using the ribonuclease protection assay. Quantitative data were collected by scanning densitometry and phosphorimaging technology. There was a dramatic increase in human brain CYP2E1 content around gestational day 50 and a fairly constant level was maintained throughout the early fetal period, until at least day 113. The relatively low levels of the P-450 isoform present in conceptal brain may be sufficient to generate reactive intermediates that elicit neuroembryotoxicity following maternal alcohol consumption.

  15. Rpe65 Leu450Met variant is associated with reduced levels of the retinal pigment epithelium lipofuscin fluorophores A2E and iso-A2E.

    Science.gov (United States)

    Kim, So Ra; Fishkin, Nathan; Kong, Jian; Nakanishi, Koji; Allikmets, Rando; Sparrow, Janet R

    2004-08-10

    There is a growing body of evidence that the nondegradable fluorophores that accumulate as the lipofuscin of retinal pigment epithelium (RPE) are involved in mechanisms leading to the degeneration of RPE in macular degeneration. Most of the constituents of RPE lipofuscin are inadvertent products of the retinoid visual cycle, the enzymatic pathway by which the 11-cis-retinal chromophore of rhodopsin is generated. Indeed, a major constituent of RPE lipofuscin, the pyridinium bisretinoid A2E, is a diretinal conjugate that forms in photoreceptor cells and is deposited in RPE cells as a consequence of the phagocytosis of the outer segment membrane by RPE cells. Given the adverse effects of A2E, there is considerable interest in combating its deposition so as to protect against vision loss. These efforts, however, necessitate an understanding of factors that modulate its formation. Here we show that an amino acid variant in murine Rpe65, a visual-cycle protein required for the regeneration of 11-cis-retinal, is associated with reduced A2E accumulation.

  16. Autophagy Protects against CYP2E1/Chronic Ethanol-Induced Hepatotoxicity

    Directory of Open Access Journals (Sweden)

    Yongke Lu

    2015-10-01

    Full Text Available Autophagy is an intracellular pathway by which lysosomes degrade and recycle long-lived proteins and cellular organelles. The effects of ethanol on autophagy are complex but recent studies have shown that autophagy serves a protective function against ethanol-induced liver injury. Autophagy was found to also be protective against CYP2E1-dependent toxicity in vitro in HepG2 cells which express CYP2E1 and in vivo in an acute alcohol/CYPE1-dependent liver injury model. The goal of the current report was to extend the previous in vitro and acute in vivo experiments to a chronic ethanol model to evaluate whether autophagy is also protective against CYP2E1-dependent liver injury in a chronic ethanol-fed mouse model. Wild type (WT, CYP2E1 knockout (KO or CYP2E1 humanized transgenic knockin (KI, mice were fed an ethanol liquid diet or control dextrose diet for four weeks. In the last week, some mice received either saline or 3-methyladenine (3-MA, an inhibitor of autophagy, or rapamycin, which stimulates autophagy. Inhibition of autophagy by 3-MA potentiated the ethanol-induced increases in serum transaminase and triglyceride levels in the WT and KI mice but not KO mice, while rapamycin prevented the ethanol liver injury. Treatment with 3-MA enhanced the ethanol-induced fat accumulation in WT mice and caused necrosis in the KI mice; little or no effect was found in the ethanol-fed KO mice or any of the dextrose-fed mice. 3-MA treatment further lowered the ethanol-decrease in hepatic GSH levels and further increased formation of TBARS in WT and KI mice, whereas rapamycin blunted these effects of ethanol. Neither 3-MA nor rapamycin treatment affected CYP2E1 catalytic activity or content or the induction CYP2E1 by ethanol. The 3-MA treatment decreased levels of Beclin-1 and Atg 7 but increased levels of p62 in the ethanol-fed WT and KI mice whereas rapamycin had the opposite effects, validating inhibition and stimulation of autophagy, respectively. These

  17. Defining the Pseudomonas Genus: Where Do We Draw the Line with Azotobacter?

    DEFF Research Database (Denmark)

    Özen, Asli Ismihan; Ussery, David

    2012-01-01

    genome family trees based on conserved gene families also show A. vinelandii to be more closely related to Pseudomonas than other related organisms. Third, exhaustive BLAST comparisons demonstrate that the fraction of shared genes between A. vinelandii and Pseudomonas genomes is similar...... using three genomic sequence-based methods. First, using 16S rRNA trees, it is shown that A. vinelandii groups within the Pseudomonas close to Pseudomonas aeruginosa. Genomes from other related organisms (Acinetobacter, Psychrobacter, and Cellvibrio) are outside the Pseudomonas cluster. Second, pan...

  18. Presenting Influenza A M2e Antigen on Recombinant Spores of Bacillus subtilis.

    Directory of Open Access Journals (Sweden)

    Tomasz Łęga

    Full Text Available Effective vaccination against influenza virus infection is a serious problem mainly due to antigenic variability of the virus. Among many of investigated antigens, the extracellular domain of the M2 protein (M2e features high homology in all strains of influenza A viruses and antibodies against M2e and is protective in animal models; this makes it a potential candidate for generation of a universal influenza vaccine. However, due to the low immunogenicity of the M2e, formulation of a vaccine based on this antigen requires some modification to induce effective immune responses. In this work we evaluated the possible use of Bacillus subtilis spores as a carrier of the Influenza A M2e antigen in mucosal vaccination. A tandem repeat of 4 consensus sequences coding for human-avian-swine-human M2e (M2eH-A-S-H peptide was fused to spore coat proteins and stably exposed on the spore surface, as demonstrated by the immunostaining of intact, recombinant spores. Oral immunization of mice with recombinant endospores carrying M2eH-A-S-H elicited specific antibody production without the addition of adjuvants. Bacillus subtilis endospores can serve as influenza antigen carriers. Recombinant spores constructed in this work showed low immunogenicity although were able to induce antibody production. The System of influenza antigen administration presented in this work is attractive mainly due to the omitting time-consuming and cost-intensive immunogen production and purification. Therefore modification should be made to increase the immunogenicity of the presented system.

  19. Ethanol-mediated transplacental induction of CYP2E1 in fetal rat liver.

    Science.gov (United States)

    Carpenter, S P; Savage, D D; Schultz, E D; Raucy, J L

    1997-08-01

    We examined the potential for the widely consumed xenobiotic ethanol to transplacentally induce fetal rat CYP2E1. Throughout gestation, rat dams were fed a liquid diet containing 5% ethanol or two separate control diets. At 2 days before term, the dams were killed, and maternal and embryonic tissues were collected. Immunoblot analysis of microsomes from fetal liver, placenta and maternal brain revealed a band that comigrated with adult liver CYP2E1. The identity of the immunoreactive protein in placenta, brain and fetal liver was substantiated as CYP2E1 through restriction enzyme digestion of a reverse transcription-polymerase chain reaction product. Quantification of immunoblots containing microsomes from maternal and fetal liver of ethanol-treated dams displayed a 1.4- and 2.4-fold increase in CYP2E1, respectively, compared with microsomes from pair-fed controls. Chlorzoxazone and low substrate concentrations of N-nitrosodimethylamine were used as metabolic probes for CYP2E1. The rate of chlorzoxazone metabolism by maternal hepatic microsomes from dams fed the 5% ethanol diet was 2.6-fold greater than that of controls. Conversely, a negligible increase was observed in the rate of metabolism by hepatic microsomes from ethanol-exposed fetuses compared with pair-fed animals. When N-nitrosodimethylamine demethylation was examined, these same fetal samples exhibited greater rates of activity (1.5-fold) compared with microsomes from control animals. However, this increase was not as great as expected considering the 2.4-fold increase in CYP2E1 protein. Collectively, fetuses exposed to a 5% ethanol diet throughout gestation exhibited transplacental induction of an hepatic CYP2E1 that may possess different catalytic properties from the analogous adult enzyme.

  20. Prevalence of multi-drug resistance (MDR) Pseudomonas ...

    African Journals Online (AJOL)

    Prevalence of multi-drug resistance (MDR) Pseudomonas aeruginosa isolates in surgical units of Ahmadu Bello University teaching Hospital, Zaria, Nigeria: An ... The antibiotic susceptibility of isolates and a standard strain to ceftazidime, amikacin, gentamicin, imipenem, ciprofloxacin and perfloxacin was determined by the ...

  1. Utilization of petroleum hydrocarbons by Pseudomonas sp. and ...

    African Journals Online (AJOL)

    This phenotype was not transformed to Pseudomonas by conjugation even with lysozyme treatment, however the petroleum oil and octadecane utilization were transformed to E. coli by lysozyme treatment. The transformed E. coli lost the ability to use octadecane after three subcultures on nutrient broth and 34 generations.

  2. Genomic and metabolic characterization of spoilage-associated Pseudomonas species.

    Science.gov (United States)

    Stanborough, Tamsyn; Fegan, Narelle; Powell, Shane M; Singh, Tanoj; Tamplin, Mark; Chandry, P Scott

    2018-03-02

    Pseudomonas are common spoilage agents of aerobically stored fresh foods. Their ability to cause spoilage is species- and may be strain-specific. To improve our understanding of the meat and milk spoilage agents Pseudomonas fragi and Pseudomonas lundensis, we sequenced the genomes of 12 P. fragi and seven P. lundensis isolates. These genomes provided a dataset for genomic analyses. Key volatile organic compounds (VOCs) produced or metabolised by the isolates were determined during their growth on a beef paste and where possible, metabolic activity was associated with gene repertoire. Genome analyses showed that the isolates included in this work may belong to more than two Pseudomonas species with possible spoilage potential. Pan-genome analyses demonstrated a high degree of diversity among the P. fragi and genetic flexibility and diversity may be traits of both species. Growth of the P. lundensis isolates was characterised by the production of large amounts of 1-undecene, 5-methyl-2-hexanone and methyl-2-butenoic acid. P. fragi isolates produced extensive amounts of methyl and ethyl acetate and the production of methyl esters predominated over ethyl esters. Some of the P. fragi produced extremely low levels of VOCs, highlighting the importance of strain-specific studies in food matrices. Furthermore, although usually not considered to be denitrifiers, all isolates generated molecular nitrogen, indicating that at least some steps of this pathway are intact. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Elastase Deficiency Phenotype of Pseudomonas aeruginosa Canine Otitis Externa Isolates

    OpenAIRE

    Petermann, Shana R.; Doetkott, Curt; Rust, Lynn

    2001-01-01

    Pseudomonas aeruginosa veterinary isolates were assayed for elastase and total matrix protease activity. The elastase activity of canine ear isolates was much less than that of strain PAO1 and that of all other veterinary isolates (P < 0.0001). The results indicate that canine ear isolates have a distinct elastase phenotype.

  4. An update on Pseudomonas aeruginosa biofilm formation, tolerance, and dispersal

    DEFF Research Database (Denmark)

    Harmsen, Morten; Yang, Liang; Pamp, Sünje Johanna

    2010-01-01

    We review the recent advances in the understanding of the Pseudomonas aeruginosa biofilm lifestyle from studies using in vitro laboratory setups such as flow chambers and microtiter trays. Recent work sheds light on the role of nutrients, motility, and quorum sensing in structure formation in P. ...

  5. extracts of senna siamea (lam) on pseudomonas aeruginosa

    African Journals Online (AJOL)

    DR. AMINU

    2009-05-30

    May 30, 2009 ... convulsion in children (Alli – Smith, 2009). In an attempt to rationally identify which pathogen to screen, Pseudomonas aeruginosa was epidemiologically identified as the hardiest bacterium that constitutes problems to researchers and clinicians. As literature showed, the hardy nature of Ps aeruginosa is ...

  6. Biological production of monoethanolamine by engineered Pseudomonas putida S12

    NARCIS (Netherlands)

    Foti, M.J.; Médici, R.; Ruijssenaars, H.J.

    2013-01-01

    Pseudomonas putida S12 was engineered for the production of monoethanolamine (MEA) from glucose via the decarboxylation of the central metabolite l-serine, which is catalyzed by the enzyme l-serine decarboxylase (SDC).The host was first evaluated for its tolerance towards MEA as well as its

  7. an tibiotic resistance trend of pseudomonas aeruginosa'in port

    African Journals Online (AJOL)

    AN TIBIOTIC RESISTANCE TREND OF PSEUDOMONAS AERUGINOSA'IN PORT. HARCOURT oaursca. 0. K}. ONYEJEPU, N 1. 1. Department of Medical Microbiology and Parasitology. University of Port Harcourt Teaching Hospital. Port Harcourt. 2. Nigerian Institute of Medical Research. 6 Edmond Crescent, Yabl. Lagos.

  8. Secretion of elastinolytic enzymes and their propeptides by Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Braun, P; de Groot, A; Bitter, W; Tommassen, J

    Elastase of Pseudomonas aeruginosa is synthesized as a preproenzyme. The signal sequence is cleaved ol during transport across the inner membrane and, in the periplasm, proelastase is further processed. We demonstrate that the propeptide and the mature elastase are both secreted but that the

  9. Induction of beta-lactamase production in Pseudomonas aeruginosa biofilm

    DEFF Research Database (Denmark)

    Giwercman, B; Jensen, E T; Høiby, N

    1991-01-01

    Imipenem induced high levels of beta-lactamase production in Pseudomonas aeruginosa biofilms. Piperacillin also induced beta-lactamase production in these biofilms but to a lesser degree. The combination of beta-lactamase production with other protective properties of the biofilm mode of growth...

  10. The cytotoxin of Pseudomonas aeruginosa : Cytotoxicity requires proteolytic activation

    NARCIS (Netherlands)

    Orlik-Eisel, Gabriele; Lutz, Frieder; Henschen, Agnes; Eisel, Ulrich; Struckmeier, Martin; Kräuter, Josef; Niemann, Heiner

    The primary structure of a cytotoxin from Pseudomonas aeruginosa was determined by sequencing of the structural gene. The cytotoxin (31,700 Mr) lacks an N-terminal signal sequence for bacterial secretion but contains a pentapeptide consensus sequence commonly found in prokaryotic proteins which

  11. Heavy Metal uptake Potentials of Pseudomonas aeruginosa and ...

    African Journals Online (AJOL)

    Uptake of heavy metals, silver and cadmium by Pseudomonas aeruginosa (a Gram negative bacterium) and Micrococcus luteus (a Gram positive bacterium) was investigated in Cadmium and Silver stock solution using ion selective electrodes. Silver and cadmium uptake by the two organisms was described by Langmuir ...

  12. Dechlorination of 1,2– dichloroethane by Pseudomonas aeruginosa ...

    African Journals Online (AJOL)

    As part of our attempt at isolating and stocking some indigenous microbial species, we isolated a bacterium from a waste dumpsite with appreciable dechlorination activity. 16S rDNA profiling revealed the isolate to be a strain of Pseudomonas aeruginosa and the sequence has been deposited in the NCBI nucleotide ...

  13. Antibiotic sensitivity of isolates of Pseudomonas aeruginosa in ...

    African Journals Online (AJOL)

    The pattern of antibiotic sensitivity of 229 clinical isolates of Pseudomonas aeruginosa isolated between June 1998 and May 2000 at the University of Nigeria Teaching Hospital (UNTH) Enugu was studied. The isolates were recovered from various clinical specimens by culturing on standard media viz: blood agar, ...

  14. Rhamnolipid stimulates uptake of hydrophobic compounds by Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Noordman, WH; Janssen, DB

    The biodegradation of hexadecane by five biosurfactant-producing bacterial strains (Pseudomonas aeruginosa UG2, Acinetobacter calcoaceticus RAG1, Rhodococcus erythropolis DSM 43066, R. erythropolis ATCC 19558, and strain BCG112) was determined in the presence and absence of exogenously added

  15. Effects of the Consortium of Pseudomonas, Bacillus and ...

    African Journals Online (AJOL)

    BSN

    degrading microorganisms in oil-polluted site. (Atlas, 1981). Crude oil biodegradation can occur under both aerobic and anaerobic conditions (Zengler et al., 1999). This research was aimed at investigating the effects of the consortium of Pseudomonas, Bacillus and. Micrococcus spp on polycyclic aromatic hydrocarbons in ...

  16. Isolation and characterization of gallium resistant Pseudomonas aeruginosa mutants

    NARCIS (Netherlands)

    García-Contreras, R; Lira-Silva, E; Jasso-Chávez, R; Hernández-González, I.L.; Maeda, T.; Hashimoto, T.; Boogerd, F.C.; Sheng, L; Wood, TK; Moreno-Sánchez, R

    2013-01-01

    Pseudomonas aeruginosa PA14 cells resistant to the novel antimicrobial gallium nitrate (Ga) were developed using transposon mutagenesis and by selecting spontaneous mutants. The mutants showing the highest growth in the presence of Ga were selected for further characterization. These mutants showed

  17. Decrease of Pseudomonas aeruginosa biofilm formation by food waste materials

    Czech Academy of Sciences Publication Activity Database

    Maděrová, Z.; Horská, K.; Kim, S.-R.; Lee, Ch.-H.; Pospíšková, K.; Šafaříková, Miroslava; Šafařík, Ivo

    2016-01-01

    Roč. 73, č. 9 (2016), s. 2143-2149 ISSN 0273-1223 Institutional support: RVO:60077344 Keywords : biofilm * food waste materials * magnetic spent grain * Pseudomonas aeruginosa Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.197, year: 2016

  18. Characterization of Pseudomonas species causing brown blotch of Agaricus bisporis.

    NARCIS (Netherlands)

    Wolf, van der J.M.; Kastelein, P.; Krijger, M.C.; Hendriks, M.J.A.; Baars, J.J.P.; Amsing, J.G.M.; Lee, van der T.A.J.; Warris, S.

    2016-01-01

    Bacterial blotch is occasionally causing damage in the production of common mushroom (Agaricus bisporus). The disease is found worldwide and can be caused by different fluorescent Pseudomonas species present in casing material. For identification of the causative agents of blotch in the Netherlands

  19. dichloroethane by Pseudomonas aeruginosa OK1 isolated from a ...

    African Journals Online (AJOL)

    Administrator

    chlorinated organics such as monochloroacetic acid, trichloroacetic acid, dichloromethane, trichloromethane and tetrachloromethane at pH 7.5 and 9.0. Optimum temperature for dehalogenase activity against 1, 2 – DCE was 35oC. Key words: Dechlorination, 16S rDNA, bioremediation, Pseudomonas aeruginosa OK1.

  20. Unraveling root developmental programs initiated by beneficial Pseudomonas spp. bacteria

    NARCIS (Netherlands)

    Zamioudis, C.; Mastranesti, P.; Dhonukshe, P.; Blilou, I.; Pieterse, C.M.J.

    2013-01-01

    Plant roots are colonized by an immense number of microbes, referred to as the root microbiome. Selected strains of beneficial soil-borne bacteria can protect against abiotic stress and prime the plant immune system against a broad range of pathogens. Pseudomonas spp. rhizobacteria represent one of

  1. Unraveling Root Developmental Programs Initiated by Beneficial Pseudomonas spp. Bacteria

    NARCIS (Netherlands)

    Zamioudis, C.; Mastranesti, P.; Dhonukshe, P.; Blilou, I.; Pieterse, C.M.J.

    2013-01-01

    Plant roots are colonized by an immense number of microbes, referred to as the root microbiome. Selected strains of beneficial soil-borne bacteria can protect against abiotic stress and prime the plant immune system against a broad range of pathogens. Pseudomonas spp. rhizobacteria represent one of

  2. Screening of thermophilic neutral lipase-producing Pseudomonas ...

    African Journals Online (AJOL)

    From oil-contaminated soil, three lipase-producing microorganisms were selected as good lipase producers using rhodamine B-olive oil plate agar and they were identified as from Pseudomonas, Burkholderia and Klebsiella genera by morphology, biochemical characterization and 16S rRNA gene sequencing. Among the ...

  3. Enhanced alpha-galactosidase expression in pseudomonas chlororaphis

    Science.gov (United States)

    Pseudomonas chlororaphis is a non-pathogenic bacterium useful for fermentative production of biopolymer (i.e., poly(hydroxyalkanoates); PHA) and biosurfactant (i.e., rhamnolipid; RhL). In order to enable P. chlororaphis to better fermentatively utilize the residual soy sugars in soy molasses – a lo...

  4. Effect of biosurfactant from two strains of Pseudomonas on ...

    African Journals Online (AJOL)

    Two Pseudomonas strains isolated from oil-contaminated soil which produce biosurfactant were studied. The biosurfactant containing broth formed stable emulsions with liquid light paraffin, cooking medium vegetable oil and toluene. The strains under study produce extra cellular biosurfactant in the culture media.

  5. Characterization of Pseudomonas aeruginosa Chitinase, a Gradually Secreted Protein

    NARCIS (Netherlands)

    Folders, J. (Jindra); Algra, J. (Jon); Roelofs, M.S. (Marc); Loon, L.C. van; Tommassen, J.P.M.; Bitter, Wilbert

    2001-01-01

    The gram-negative bacterium Pseudomonas aeruginosa secretes many proteins into its extracellular environment via the type I, II, and III secretion systems. In this study, a gene, chiC, coding for an extracellular chitinolytic enzyme, was identified. The chiC gene encodes a polypeptide of 483 amino

  6. Effect of alternating and direct currents on Pseudomonas ...

    African Journals Online (AJOL)

    ONOS

    2010-09-20

    Sep 20, 2010 ... studies must be done so as to reach optimum voltage and currents. The test media were Muller-Hinton agar and eosin methylene blue (EMB) agar. In this research Pseudomonas aeruginosa which was isolated from patients׳ wounds was examined with levels of alternating and direct current (AC and DC).

  7. Effect of alternating and direct currents on Pseudomonas ...

    African Journals Online (AJOL)

    In this research Pseudomonas aeruginosa which was isolated from patients wounds was examined with levels of alternating and direct current (AC and DC) electrical stimulation (1.5V, 3.5V, 5.5V and 10V) to see if these currents could inhibit P. aeruginosa growth in vitro. The experiment was performed in two forms: The first ...

  8. Pseudomonas aeruginosa burn wound infection in a dedicated ...

    African Journals Online (AJOL)

    Background. Pseudomonas aeruginosa infection is a major cause of morbidity in burns patients. There is a paucity of publications dealing with this infection in the paediatric population. We describe the incidence, microbiology and impact of P. aeruginosa infection in a dedicated paediatric burns unit. Methods.

  9. Utilization of petroleum hydrocarbons by Pseudomonas sp. and ...

    African Journals Online (AJOL)

    pseudomonas isolated from a petroleum-contaminated soil was instable. In this work, t is shown that when the isolates are immobilized on Perlite, they are more stable for oil egradation. Although the isolate did not have any chemotaxis to ...

  10. High Temperature Induced Antibiotic Sensitivity in Pseudomonas aeruginosa.

    Science.gov (United States)

    1984-08-01

    aeruginosa ATCC 9027 was maintained on Pseudomonas P agar slants (Difco Laboratories, Detroit, MI.). The organism was cultivated at 37°C or 46°C in a proteose...Studies on the permeability change produced in coliform bacteria by ethylene diamine tetracetate. J. Biol. Chem. 243: 2372 - 2380. 7. 9. Lowry, O.H., N.J

  11. Isolation and characterization of Pseudomonas resistant to heavy ...

    African Journals Online (AJOL)

    Isolation and characterization of Pseudomonas resistant to heavy metals and poly aromatics hydrocarbons (PAHs) from Persian Gulf sediments. ... Among 10 bacterial species isolated from marine sediment, one strain represented high potential to grow in medium supplemented with copper and phenanthrene. Isolated ...

  12. The Transcriptional Landscape of the Production Organism Pseudomonas putida

    DEFF Research Database (Denmark)

    D'Arrigo, Isotta

    Bacterial cell factories represent a valid alternative to fossil fuel-based production. A promising bacterium that can be optimized as cell factory is Pseudomonas putida. However, its development in bioproduction applications poses some challenges including a clear understanding of the bacterial ...

  13. Detection of Pseudomonas fluorescens from broth, water and ...

    African Journals Online (AJOL)

    Loop mediated isothermal amplification is rapid, highly sensitive and specifically developed method for detection of bacterial infections. AprX gene for alkaline metalloprotease of Pseudomonas fluorescens was used to design four primers and loop mediated isothermal amplification (LAMP) conditions were standardized for ...

  14. Metabolism of amino acid amides in Pseudomonas putida ATCC 12633

    NARCIS (Netherlands)

    Hermes, H.F.M.; Croes, L.M.; Peeters, W.P.H.; Peters, P.J.H.; Dijkhuizen, L.

    1993-01-01

    The metabolism of the natural amino acid L-valine, the unnatural amino acids D-valine, and D-, L-phenylglycine (D-, L-PG), and the unnatural amino acid amides D-, L-phenylglycine amide (D, L-PG-NH2) and L-valine amide (L-Val-NH2) was studied in Pseudomonas putida ATCC 12633. The organism possessed

  15. Characterization of the chlorate reductase from Pseudomonas chloritidismutans

    NARCIS (Netherlands)

    Wolterink, A.F.W.M.; Schiltz, E.; Hagedoorn, P.L.; Hagen, W.R.; Kengen, S.W.M.; Stams, A.J.M.

    2003-01-01

    A chlorate reductase has been purified from the chlorate-reducing strain Pseudomonas chloritidismutans. Comparison with the periplasmic (per)chlorate reductase of strain GR-1 showed that the cytoplasmic chlorate reductase of P. chloritidismutans reduced only chlorate and bromate. Differences were

  16. Effects of the Consortium of Pseudomonas , Bacillus and ...

    African Journals Online (AJOL)

    The effect of the consortium of Pseudomonas, Bacillus and Micrococcus spp on polycyclic aromatic hydrocarbons in crude oil was carried out using standard microbiological methods. Spectrophotometer, gas chromatography and viable count which determined the optical density, the polycyclic aromatic hydrocarbons and ...

  17. Effects of the Consortium of Pseudomonas, Bacillus and ...

    African Journals Online (AJOL)

    The effect of the consortium of Pseudomonas, Bacillus and Micrococcus spp on polycyclic aromatic hydrocarbons in crude oil was carried out using standard microbiological methods. Spectrophotometer, gas chromatography and viable count which determined the optical density, the polycyclic aromatic hydrocarbons and ...

  18. Effects of the Consortium of Pseudomonas, Bacillus and ...

    African Journals Online (AJOL)

    Johnny

    Abstract. The effect of the consortium of Pseudomonas, Bacillus and Micrococcus spp on polycyclic aromatic hydrocarbons in crude oil was carried out using standard microbiological methods. Spectrophotometer, gas chromatography and viable count which determined the optical density, the polycyclic aromatic ...

  19. Multiple Antibiotic Resistance (MAR) indices of Pseudomonas and ...

    African Journals Online (AJOL)

    Background/Objectives: Pseudomonas and Klebsiella infections are important nosocomial infections because of the attendant significant morbidity, mortality and socio-economic impact. These infections are difficult to treat due to the innate and acquired resistance mediated by the organisms' genome and other transferable ...

  20. Production of a rhamnolipid-type biosurfactant by Pseudomonas ...

    African Journals Online (AJOL)

    The work herewith investigated the effect of the culture medium composition on rhamnolipid production by Pseudomonas aeruginosa LBM10, previously isolated from an estuarine environment in Southern Brazil. Experimental design and surface response methodology were used in order to improve biosurfactant ...

  1. Isolation, purification and properties of lipase from Pseudomonas ...

    African Journals Online (AJOL)

    user

    2012-07-26

    Jul 26, 2012 ... Isolate Ps5 showed the highest lipase activity which was later identified as Pseudomonas aeruginosa. The effect of ..... Identification and characterization of a locally isolated lipolytic microfungus Geotrichum candidum. Malaysian J. Microbiol. 2: 22-29. Martinelle M, Hult K (1995).Kinetics of acyl transfer ...

  2. [Activity of doripenem against Pseudomonas spp. and Acinetobacter spp. rods].

    Science.gov (United States)

    Bogiel, Tomasz; Deptuła, Aleksander; Gospodarek, Eugenia

    2009-01-01

    Doripenem, the newest carbapenem was approved in 2008 by the European Medicines Agency for the treatment of complicated intra-abdominal infections and complicated urinary tract infections. Its spectrum of activity is similar to that of meropenem and imipenem/cilastatin. The aim of this study was to compare in vitro activity of doripenem against nonfermentative Gram-negative rods. A total of 235 strains of Pseudomonas spp. (74.9%) and Acinetobacter spp. (25.1%) were included into the study. Strains were isolated in The Department of Clinical Microbiology of the University Hospital No 1 in Bydgoszcz and identified using ID GN tests (bioMérieux). To determine susceptibility to doripenem and other carbapenems disc-diffusion method was applied. Percentage of doripenem resistant strains reached 28.4% and 39.0% for Pseudomonas spp. and Acinetobacter spp, respectively. All doripenem sensitive or intermediate Acinetobacter spp. strains were simultaneously sensitive to imipenem and meropenem. Activity of imipenem and meropenem among doripenem resistant Acinetobacter spp. were represented by 60.9% and 56.5% strains, respectively. Activity of imipenem and meropenem among doripenem resistant Pseudomonas spp. strains were represented by 12.0% and 18.0%, respectively. Occurence of one doripenem sensitive Pseudomonas spp. strain simultaneously resistant to imipenem and meropenem was observed.

  3. Isolation and characterization of Pseudomonas putida WLY for ...

    African Journals Online (AJOL)

    The azoreductase produced by P. putida WLY was extracellular and induced according to electrophoresis experiments and decolorization tests. After purification by ion exchange and gel chromatography, its molecular weight was estimated to be 28,000 Da by SDS-PAGE. Key words: Pseudomonas putida; reactive brilliant ...

  4. Isolation, purification and properties of lipase from Pseudomonas ...

    African Journals Online (AJOL)

    Six isolates (Ps1, Ps2, Ps3, Ps4, Ps5 and Ps6) producing lipase were screened from wastewater on a selective medium agar containing Tween 80 or olive oil as the only source of carbon. Isolate Ps5 showed the highest lipase activity which was later identified as Pseudomonas aeruginosa. The effect of media composition ...

  5. Interaction between fish spoilage bacteria Pseudomonas sp and Shewanella putrefaciens in fish extracts and on fish tissue

    DEFF Research Database (Denmark)

    Gram, Lone; Melchiorsen, Jette

    1996-01-01

    , supernatant fluids from siderophore- negative Pseudomonas isolates did not inhibit growth of S. putrefaciens. The inhibitory effect was, except for one strain of Pseudomonas, not seen in supernatant fluids from iron- enriched cultures of Pseudomonas sp. Finally, siderophore- producing Pseudomonas sp. lowered...

  6. Pseudomonas guariconensis sp. nov., isolated from rhizospheric soil.

    Science.gov (United States)

    Toro, Marcia; Ramírez-Bahena, Martha-Helena; Cuesta, Maria José; Velázquez, Encarna; Peix, Alvaro

    2013-12-01

    We isolated a bacterial strain designated PCAVU11(T) in the course of a study of phosphate-solubilizing bacteria occurring in rhizospheric soil of Vigna unguiculata (L.) Walp. in Guárico state, Venezuela. The 16S rRNA gene sequence had 99.2 % sequence similarity with respect to the most closely related species, Pseudomonas taiwanensis, and 99.1 % with respect to Pseudomonas entomophila, Pseudomonas plecoglossicida and Pseudomonas monteilii, on the basis of which PCAVU11(T) was classified as representing a member of the genus Pseudomonas. Analysis of the housekeeping genes rpoB, rpoD and gyrB confirmed the phylogenetic affiliation and showed sequence similarities lower than 95 % in all cases with respect to the above-mentioned closest relatives. Strain PCAVU11(T) showed two polar flagella. The respiratory quinone was Q9. The major fatty acids were 16 : 0 (25.7 %), 18 : 1ω7c (20.4 %), 17 : 0 cyclo (11.5 %) and 16 : 1ω7c/15 : 0 iso 2-OH in summed feature 3 (10.8 %). The strain was oxidase-, catalase- and urease-positive, the arginine dihydrolase system was present but nitrate reduction, β-galactosidase production and aesculin hydrolysis were negative. Strain PCAVU11(T) grew at 44 °C and at pH 10. The DNA G+C content was 61.5 mol%. DNA-DNA hybridization results showed values lower than 56 % relatedness with respect to the type strains of the four most closely related species. Therefore, the results of genotypic, phenotypic and chemotaxonomic analyses support the classification of strain PCAVU11(T) as representing a novel species of the genus Pseudomonas, which we propose to name Pseudomonas guariconensis sp. nov. The type strain is PCAVU11(T) ( = LMG 27394(T) = CECT 8262(T)).

  7. Specific Genomic Fingerprints of Phosphate Solubilizing Pseudomonas Strains Generated by Box Elements

    Science.gov (United States)

    Javadi Nobandegani, Mohammad Bagher; Saud, Halimi Mohd; Yun, Wong Mui

    2014-01-01

    Primers corresponding to conserved bacterial repetitive of BOX elements were used to show that BOX-DNA sequences are widely distributed in phosphate solubilizing Pseudomonas strains. Phosphate solubilizing Pseudomonas was isolated from oil palm fields (tropical soil) in Malaysia. BOX elements were used to generate genomic fingerprints of a variety of Pseudomonas isolates to identify strains that were not distinguishable by other classification methods. BOX-PCR, that derived genomic fingerprints, was generated from whole purified genomic DNA by liquid culture of phosphate solubilizing Pseudomonas. BOX-PCR generated the phosphate solubilizing Pseudomonas specific fingerprints to identify the relationship between these strains. This suggests that distribution of BOX elements' sequences in phosphate solubilizing Pseudomonas strains is the mirror image of their genomic structure. Therefore, this method appears to be a rapid, simple, and reproducible method to identify and classify phosphate solubilizing Pseudomonas strains and it may be useful tool for fast identification of potential biofertilizer strains. PMID:25580434

  8. CYP2E1 Potentiates Ethanol-induction of Hypoxia and HIF-1α in vivo

    Science.gov (United States)

    Wang, Xiaodong; Wu, Defeng; Yang, Lili; Gan, Lixia; Cederbaum, Arthur I

    2013-01-01

    Ethanol induces hypoxia and elevates HIF-1α in the liver. CYP2E1 plays a role in the mechanisms by which ethanol generates oxidative stress, fatty liver and liver injury. The current study evaluated whether CYP2E1 contributes to ethanol-induced hypoxia and activation of HIF-1α in vivo and whether HIF-1α protects against or promotes CYP2E1-dependent toxicity in vitro. Wild type (WT), CYP2E1-knockin (KI) and CYP2E1 knockout (KO) mice were fed ethanol chronically; pair fed controls received isocaloric dextrose. Ethanol produced liver injury in the KI mice to a much greater extent than in the WT and KO mice. Protein levels of HIF-1α and downstream targets of HIF-1α activation were elevated in the ethanol-fed KI mice compared to the WT and KO mice. Levels of HIF prolylhydroxlase 2 which promotes HIF-1α degradation were decreased in the ethanol-fed KI mice in association with the increases in HIF-1α. Hypoxia occurred in the ethanol-fed CYP2E1 KI mice as shown by an increased area of staining using the hypoxia-specific marker pimonidazole. Hypoxia was lower in the ethanol-fed WT mice and lowest in the ethanol fed KO mice and all the dextrose-fed mice. In situ double staining showed that pimonidazole and CYP2E1 were co-localized to the same area of injury in the hepatic centrilobule. Increased protein levels of HIF-1α were also found after acute ethanol treatment of KI mice. Treatment of HepG2 E47 cells which express CYP2E1 with ethanol plus arachidonic (AA) acid or ethanol plus buthionine sulfoximine (BSO) which depletes GSH caused loss of cell viability to greater extent than in HepG2 C34 cells which do not express CYP2E1. These treatments elevated protein levels of HIF-1α to a greater extent in E47 cells than C34 cells. 2-Methoxyestradiol, an inhibitor of HIF-1α, blunted the toxic effects of ethanol plus AA and ethanol plus BSO in the E47 cells in association with inhibition of HIF-1α. The HIF-1α inhibitor also blocked the elevated oxidative stress produced

  9. Inhibition of urethane-induced genotoxicity and cell proliferation in CYP2E1-null mice

    Energy Technology Data Exchange (ETDEWEB)

    Hoffler, Undi [Department of Pharmacology, Meharry Medical College, Nashville, TN (United States); Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institute of Health, Research Triangle Park, NC 27709 (United States); Dixon, Darlene [Laboratory of Experimental Pathology, National Institute of Environmental Health Sciences, National Institute of Health, Research Triangle Park, NC 27709 (United States); Peddada, Shyamal [Biostatics Branch, National Institute of Environmental Health Sciences, National Institute of Health, Research Triangle Park, NC 27709 (United States); Ghanayem, Burhan I. [Department of Pharmacology, Meharry Medical College, Nashville, TN (United States) and Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institute of Health, Research Triangle Park, NC 27709 (United States)]. E-mail: ghanayem@niehs.nih.gov

    2005-05-02

    Urethane is a multi-site animal carcinogen and was classified as 'reasonably anticipated to be a human carcinogen.' Urethane is a fermentation by-product and found at appreciable levels in alcoholic beverages and foods such as bread and cheese. Recent work in this laboratory demonstrated for the first time that CYP2E1 is the principal enzyme responsible for urethane metabolism. The current studies were undertaken to assess the relationships between CYP2E1-mediated metabolism and urethane-induced genotoxicity and cell proliferation as determined by induction of micronucleated erythrocytes (MN) and expression of Ki-67, respectively, using CYP2E1-null and wild-type mice. Urethane was administered at 0 (vehicle), 1, 10, or 100 mg/kg/day (p.o.), 5 days/week for 6 weeks. A significant dose-dependent increase in MN was observed in wild-type mice; however, a slight increase was measured in the MN-polychromatic erythrocytes in CYP2E1-null mice treated with 100 mg/kg. A significant increase in the expression of Ki-67 was detected in the livers and the lungs (terminal bronchioles, alveoli, and bronchi) of wild-type mice administered 100 mg urethane/kg in comparison to controls. In contrast, CYP2E1-null mice administered this dose exhibited negligible alterations in Ki-67 expression in the livers and lungs compared to controls. Interestingly, while Ki-67 expression in the forestomach decreased in wild-type mice, it increased in CYP2E1-null mice. Subsequent comparative metabolism studies demonstrated that total urethane-derived radioactivity in the plasma, liver, and lung was significantly higher in CYP2E1-null versus wild-type mice and un-metabolized urethane constituted greater than 83% of the radioactivity in CYP2E1-null mice. Un-metabolized urethane was not detectable in the plasma, liver, and lung of wild-type mice. In conclusion, these data demonstrated that CYP2E1-mediated metabolism of urethane, presumably via epoxide formation, is necessary for the induction

  10. The Frequency of Cytochrome P450 2E1 Polymorphisms in Black South Africans

    Directory of Open Access Journals (Sweden)

    Paul K. Chelule

    2006-01-01

    Full Text Available Polymorphisms in the promoter region of the Cytochrome P4502E1 (CYP2E1 gene reportedly modify the metabolic activity of CYP2E1 enzyme, and have been associated with increased susceptibility to squamous cell carcinoma (SCC of the oesophagus in high prevalence areas such as China. To assess the frequency of these polymorphisms in Black South Africans, a population with a high incidence of oesophageal SCC, this study examined genomic DNA from 331 subjects for restriction fragment length polymorphisms in the CYP2E1 (RsaI and PstI digestion. The frequency of the CYP2E1 c1/c1 and c1/c3 genotypes was 95% and 5% respectively. The frequency of the CYP2E1 allele distribution was found to be markedly different between Chinese and South African populations; hence it is important to place racial differences into consideration when proposing allelic variants as genetic markers for cancer.

  11. Biosynthetic studies of A2E, a major fluorophore of retinal pigment epithelial lipofuscin.

    Science.gov (United States)

    Ben-Shabat, Shimon; Parish, Craig A; Vollmer, Heidi R; Itagaki, Yasuhiro; Fishkin, Nathan; Nakanishi, Koji; Sparrow, Janet R

    2002-03-01

    We have examined questions related to the biosynthesis of A2E, a fluorophore that accumulates in retinal pigment epithelial cells with aging and in some retinal disorders. The use of in vitro preparations revealed that detectable levels of A2-PE, the A2E precursor, are formed within photoreceptor outer segments following light-induced release of endogenous all-trans-retinal. Moreover, experiments in vivo demonstrated that the formation of A2-PE in photoreceptor outer segment membrane was augmented by exposing rats to bright light. Whereas the generation of A2E from A2-PE by acid hydrolysis was found to occur very slowly, the detection in outer segments of a phosphodiesterase activity that can convert A2-PE to A2E may indicate that some portion of the A2-PE that forms in the outer segment membrane may undergo hydrolytic cleavage before internalization by the retinal pigment epithelial cell. The identities of additional minor components of retinal pigment epithelium lipofuscin, A2E isomers with cis olefins at positions other than the C13-C14 double bond, are also described.

  12. Activation of Pseudomonas aeruginosa elastase in Pseudomonas putida by triggering dissociation of the propeptide-enzyme complex

    NARCIS (Netherlands)

    Braun, P; Bitter, W; Tommassen, J

    2000-01-01

    The propeptide of Pseudomonas aeruginosa elastase functions both as an intramolecular chaperone required for the folding of the enzyme and as an inhibitor that prevents activity of the enzyme before its secretion into the extracellular medium. Since expression of the lasB gene, which encodes

  13. LISA Pathfinder E2E performance simulation: optical and self-gravity stability analysis

    Science.gov (United States)

    Brandt, N.; Fichter, W.; Kersten, M.; Lucarelli, S.; Montemurro, F.

    2005-05-01

    End-to-end (E2E) modelling and simulation, i.e. verifying the science performance of LISA Pathfinder (spacecraft and payload), is mandatory in order to minimize mission risks. In this paper, focus is on two particular applications of the E2E performance simulator currently being developed at EADS Astrium GmbH: the opto-dynamical stability and the self-gravity disturbance stability analysis. The E2E models applied here comprise the opto-dynamical modelling of the optical metrology systems (OMS) laser interferometry, the thermo-elastic distortion modelling of the OMS optical elements and the self-gravity disturbance model accounting for structural distortions. Preliminary analysis results are presented in detail, identifying shortcomings of the current LISA technology package (LTP) mounting baseline. As a consequence, the design is now being revised.

  14. Determinación de aislados nativos de pseudomonas desulfurizadoras mediante el estudio del perfil de ácidos grasos

    Directory of Open Access Journals (Sweden)

    Edilberto Silva Gómez

    2010-09-01

    Full Text Available Utilizando CGAR se determinó el contenido de ácidos grasos celulares de doce aislados colombianos, Pseudomonas aeruginosa 17, 18, 19, 20, 21, 22 y 103, Pseudomonas sp 23, 24, 25, 26 y 27 con capacidad desulfurizadora, Pseudomonas aeruginosa ATCC 9027 y 10145, Pseudomonas sp ATCC 39327 y Pseudomonas flúores cens. Se encontraron 53 ácidos grasos diferentes, entre saturados e insaturados de cadena lineal, y principalmente hidroxiácidos y ramificados.

  15. Quercetin prevents type 1 diabetic liver damage through inhibition of CYP2E1.

    Science.gov (United States)

    Maksymchuk, Oksana; Shysh, Angela; Rosohatska, Inna; Chashchyn, Mykola

    2017-12-01

    Increased CYP2E1 protein and activity levels can be the main cause of stress-mediated liver damage in diabetes. In this work we investigated the quercetin properties to prevent diabetic oxidative liver injury through inhibition of CYP2E1. Animals were randomly divided into three groups (n=5 for each group): non-diabetic control, STZ-diabetic rats and STZ-diabetic rats administered with quercetin (50mg/kg bw, per day, during 30days). Markers of oxidative stress and liver injury, hepatocyte ultrastructure and levels of CYP2E1 protein and activity were examined using biochemical, electron microscopy and molecular biological methods. It was shown that symptoms of diabetes (hyperglycemia, bodyweight loss, damaged hepatocyte ultrastructure), signs of oxidative stress in liver (2-fold intensification of peroxide process and 2-fold depletion of antioxidants) and serum markers of liver damage (3.5-, 1.5- and 5-fold increase in levels of ALT, AST and GGT, respectively) were present in STZ-diabetic rats. We found 3- and 2.5-fold increase in levels of protein and activity of CYP2E1 in the liver of STZ-diabetic rats. We demonstrated that the administration of quercetin leads to significant decrease in CYP2E1 activity (5- and 2-times compared to STZ-diabetic and control group, respectively). That was accompanied by normalization of pro-oxidant-antioxidant balance, improving the ultrastructure of hepatocytes and rates of serum markers of liver injury. CYP2E1 can play a crucial role in stress-induced pathological processes in the liver in diabetes, and the inhibition of the enzyme by quercetin during the development of diabetes mainly prevents the oxidative damage in liver. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  16. Optimization of the muon stopping target for the MU2E collaboration

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, Zachary Donovan [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2013-01-01

    The Mu2e Experiment utilizes state of the art accelerators, superconducting magnets, detectors, electronics, and other equipment to maximize the sensitivity to such a rare process. Many of the components of the Mu2e hardware are critical to the overall physics capability of the experiment. The muon stopping target, where muons are stopped and may interact via this very rare process, is one such component where any improvements beyond the base design can have a significant impact on the experiment. This thesis explores possible modifications to the geometry of the muon stopping target. The goal is to determine if any modifications can improve the sensitivity of observing the muon conversion process.

  17. CYP2E1-dependent elevation of serum cholesterol, triglycerides, and hepatic bile acids by isoniazid

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Jie; Krausz, Kristopher W. [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Li, Feng; Ma, Xiaochao [Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, 4089 KLSIC, MS 1018, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States); Gonzalez, Frank J., E-mail: fjgonz@helix.nih.gov [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2013-01-15

    Isoniazid is the first-line medication in the prevention and treatment of tuberculosis. Isoniazid is known to have a biphasic effect on the inhibition–induction of CYP2E1 and is also considered to be involved in isoniazid-induced hepatotoxicity. However, the full extent and mechanism of involvement of CYP2E1 in isoniazid-induced hepatotoxicity remain to be thoroughly investigated. In the current study, isoniazid was administered to wild-type and Cyp2e1-null mice to investigate the potential toxicity of isoniazid in vivo. The results revealed that isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice, but produced elevated serum cholesterol and triglycerides, and hepatic bile acids in wild-type mice, as well as decreased abundance of free fatty acids in wild-type mice and not in Cyp2e1-null mice. Metabolomic analysis demonstrated that production of isoniazid metabolites was elevated in wild-type mice along with a higher abundance of bile acids, bile acid metabolites, carnitine and carnitine derivatives; these were not observed in Cyp2e1-null mice. In addition, the enzymes responsible for bile acid synthesis were decreased and proteins involved in bile acid transport were significantly increased in wild-type mice. Lastly, treatment of targeted isoniazid metabolites to wild-type mice led to similar changes in cholesterol, triglycerides and free fatty acids. These findings suggest that while CYP2E1 is not involved in isoniazid-induced hepatotoxicity, while an isoniazid metabolite might play a role in isoniazid-induced cholestasis through enhancement of bile acid accumulation and mitochondria β-oxidation. -- Highlights: ► Isoniazid metabolites were elevated only in wild-type mice. ► Isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice. ► Isoniazid elevated serum cholesterol and triglycerides, and hepatic bile acids. ► Bile acid transporters were significantly decreased in isoniazid-treated mice.

  18. Comparative genomic analysis of multiple strains of two unusual plant pathogens: Pseudomonas corrugata and Pseudomonas mediterranea

    Directory of Open Access Journals (Sweden)

    Emmanouil A Trantas

    2015-08-01

    Full Text Available The non-fluorescent pseudomonads, Pseudomonas corrugata (Pcor and P. mediterranea (Pmed, are closely related species that cause pith necrosis, a disease of tomato that causes severe crop losses. However, they also show strong antagonistic effects against economically important pathogens, demonstrating their potential for utilization as biological control agents. In addition, their metabolic versatility makes them attractive for the production of commercial biomolecules and bioremediation. An extensive comparative genomics study is required to dissect the mechanisms that Pcor and Pmed employ to cause disease, prevent disease caused by other pathogens, and to mine their genomes for commercially significant chemical pathways. Here, we present the draft genomes of nine Pcor and Pmed strains from different geographical locations. This analysis covered significant genetic heterogeneity and allowed in-depth genomic comparison. All examined strains were able to trigger symptoms in tomato plants but not all induced a hypersensitive-like response in Nicotiana benthamiana. Genome-mining revealed the absence of a type III secretion system and of known type III effectors from all examined Pcor and Pmed strains. The lack of a type III secretion system appears to be unique among the plant pathogenic pseudomonads. Several gene clusters coding for type VI secretion system were detected in all genomes.

  19. Lack of Correlation Between the Spatial Distribution of A2E and Lipofuscin Fluorescence in the Human Retinal Pigment Epithelium

    OpenAIRE

    Ablonczy, Zsolt; Higbee, Daniel; Anderson, David M.; Dahrouj, Mohammad; Grey, Angus C.; Gutierrez, Danielle; Koutalos, Yiannis; Schey, Kevin L.; Hanneken, Anne; Crouch, Rosalie K.

    2013-01-01

    This report to our knowledge is the first description of the spatial distribution of A2E in the human RPE at high resolution, which has allowed a direct comparison of A2E distribution with lipofuscin fluorescence.

  20. Expression of recombinant Pseudomonas stutzeri di-heme cytochrome c(4) by high-cell-density fed-batch cultivation of Pseudomonas putida

    DEFF Research Database (Denmark)

    Thuesen, Marianne Hallberg; Nørgaard, Allan; Hansen, Anne Merete

    2003-01-01

    The gene of the di-heme protein cytochrome c(4) from Pseudomonas stutzeri was expressed in Pseudomonas putida. High-yield expression of the protein was achieved by high-cell-density fed-batch cultivation using an exponential glucose feeding strategy. The recombinant cytochrome c(4) protein...

  1. Simple synthesis of pyrrolo[3,2-e]indole-1-carbonitriles

    OpenAIRE

    Trawczy?ski, Adam; Bujok, Robert; Wr?bel, Zbigniew; Wojciechowski, Krzysztof

    2013-01-01

    Summary Alkylation of 5-nitroindol-4-ylacetonitriles with ethyl chloroacetate, ?-halomethyl ketones, and chloroacetonitrile followed by a treatment of the products with chlorotrimethylsilane in the presence of DBU gives 1-cyanopyrrolo[3,2-e]indoles substituted in position 2 with electron-withdrawing groups.

  2. A Panel Prototype for the Mu2e Straw Tube Tracker at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Lucà, Alessandra [Fermilab

    2017-10-10

    The Mu2e experiment will search for coherent, neutrino-less conversion of muons into electrons in the Coulomb field of an aluminum nucleus with a sensitivity of four orders of magnitude better than previous experiments. The signature of this process is an electron with energy nearly equal to the muon mass. Mu2e relies on a precision (0.1%) measurement of the outgoing electron momentum to separate signal from background. In order to achieve this goal, Mu2e has chosen a very low-mass straw tracker, made of 20,736 5 mm diameter thin-walled (15 $\\mu$m) Mylar straws, held under tension to avoid the need for supports within the active volume, and arranged in an approximately 3 m long by 0.7 m radius cylinder, operated in vacuum and a 1 T magnetic field. Groups of 96 straws are assembled into modules, called panels. We present the prototype and the assembly procedure for a Mu2e tracker panel built at Fermilab

  3. A 2e Parent's Journey: Persistence, Partnership, and the Provision of Unconditional Love

    Science.gov (United States)

    Brownstein, Michelle

    2015-01-01

    I have four children, three of whom are twice exceptional in the context of the new Community of Practice (2e CoP) definition highlighted in this issue. I share a personal story of a parent's journey in persistence, partnerships, and the provision of unconditional love.

  4. Simple synthesis of pyrrolo[3,2-e]indole-1-carbonitriles

    Directory of Open Access Journals (Sweden)

    Adam Trawczyński

    2013-05-01

    Full Text Available Alkylation of 5-nitroindol-4-ylacetonitriles with ethyl chloroacetate, α-halomethyl ketones, and chloroacetonitrile followed by a treatment of the products with chlorotrimethylsilane in the presence of DBU gives 1-cyanopyrrolo[3,2-e]indoles substituted in position 2 with electron-withdrawing groups.

  5. Performance Evaluation of Triple Play Services Delivery with E2E QoS Provisioning

    Directory of Open Access Journals (Sweden)

    Nikolaos Zotos

    2010-01-01

    Full Text Available The creation and wide use of new high quality demanding services (VoIP, High Quality Video Streaming and the delivery of them over already saturated core and access network infrastructures have created the necessity for E2E QoS provisioning. Network Providers use at their infrastructures several kinds of mechanisms and techniques for providing QoS. Most known and widely used technologies are MPLS and DiffServ. The IEEE 802.16-2004 standard (WiMAX refers to a promising wireless broadband technology with enhanced QoS support algorithms. This document presents an experimental network infrastructure providing E2E QoS, using a combination of MPLS and DiffServ technologies in the core network and WiMAX technology as the wireless access medium for high priority services (VoIP, High Quality Video Streaming transmission. The main scope is to map the traffic prioritization and classification attributes of the core network to the access network in a way which does not affect the E2E QoS provisioning. The performance evaluation will be done by introducing different kinds of traffic scenarios in a saturated and overloaded network environment. The evaluation will prove that this combination made feasible the E2E QoS provisioning while keeping the initial constrains as well as the services delivered over a wireless network.

  6. MARS Tracking Simulations for the Mu2e Slow Extracted Proton Beam

    Energy Technology Data Exchange (ETDEWEB)

    Nagaslaev, Vladimir [Fermilab; Rakhno, Igor [Fermilab

    2015-06-01

    Particle tracking taking into account interactions with fields and materials is necessary for proper evaluation of the resonant extraction losses and geometry optimization for the extraction beam line. This paper describes the tracking simulations for the Mu2e Resonant Extraction and discusses the geometry choices made based on these simulations.

  7. A Topographical Atlas of Shiga Toxin 2e Receptor Distribution in the Tissues of Weaned Piglets

    Directory of Open Access Journals (Sweden)

    Daniel Steil

    2016-11-01

    Full Text Available Shiga toxin (Stx 2e of Stx-producing Escherichia coli (STEC is the primary virulence factor in the development of pig edema disease shortly after weaning. Stx2e binds to the globo-series glycosphingolipids (GSLs globotriaosylceramide (Gb3Cer, Galα1-4Galβ1-4Glcβ1-1Cer and globotetraosylceramide (Gb4Cer, GalNAcβ1-3Galα1-4Galβ1-4Glcβ1-1Cer, the latter acting as the preferential Stx2e receptor. We determined Stx receptor profiles of 25 different tissues of a male and a female weaned piglet using immunochemical solid phase binding assays combined with mass spectrometry. All probed tissues harbored GSL receptors, ranging from high (category I over moderate (category II to low content (category III. Examples of Gb4Cer expression in category I tissues are small intestinal ileum, kidney pelvis and whole blood, followed by colon, small intestinal duodenum and jejunum belonging to category II, and kidney cortex, cerebrum and cerebellum as members of category III organs holding true for both genders. Dominant Gb3Cer and Gb4Cer lipoforms were those with ceramides carrying constant sphingosine (d18:1 and a variable C16:0, C22:0 or C24:1/C24:0 fatty acid. From the mapping data, we created a topographical atlas for Stx2e receptors in piglet tissues and organs, which might be helpful to further investigations on the molecular and cellular mechanisms that underlie infections of Stx2e-producing STEC in pigs and their zoonotic potential for humans.

  8. Study of Pseudomonas Aeroginosa resistance to Penicillines, Cephalosporins and Aminoglycosides

    Directory of Open Access Journals (Sweden)

    Maleknezhad P

    1998-07-01

    Full Text Available Drug therapy and prophylaxy in infectious diseases, from hygienic and economical point of view, are very important. Infections caused by pseudomonas aeroginosa were particularly severe, with high mortality rates. In the recent years pseudomonas aeroginosa continued to cause the most severe, life-thereating infections in burned patients, in spite of the introduction of a wide variety of antibiotics advised specifically for their anti pseudomonal activity. The aim of this study, in which many cases of ps.aeroginosa infections are assessed is to identify the drug resistance of this bacteria to penicillines, cephalosporins and aminoglycosides by antibiotic sensitivity test (disk ager diffusion. Results as percent of resistance to each antibiotic were 89% to carbenicillin, 55% to piperacillin, 89% to mezlocillin, 89.5% to ticarcillin+clavulonic acid, 85% to ceftriaxone, 95% to tobramycin, 5% of all isolates were not sensitive to any antibiotics.

  9. PSEUDOMONAS AERUGINOSA IN CHRONIC SUPPURATIVE OTITIS MEDIA- A DRUGSENSITIVITY STUDY

    Directory of Open Access Journals (Sweden)

    Anoop M

    2017-05-01

    Full Text Available BACKGROUND Chronic suppurative otitis media is one among the commonest ENT disease seen in day-to-day practice. It is seen mainly among low socioeconomic class. MATERIALS AND METHODS The present study was conducted in the Department of ENT, Shadan Institute of Medical Sciences. Fifty patients with CSOM of all age groups and both sexes attending the Outpatient Department of ENT were selected randomly for the study. RESULTS From our study, we found mainly children of age group 10-11 years commonly affected. They belong to poor socioeconomic background. Pseudomonas aeruginosa is the most common organism isolated in the present study. Ciprofloxacin was found to be the most sensitive antibiotic to Pseudomonas aeruginosa. CONCLUSION We noticed that drug resistance is on the rise due to misuse of antibiotics, over-the-counter treatment, inadequate period of therapy and less awareness among public regarding drug resistance. Constant monitoring of antibiotic sensitivity is needed to prevent drug resistance in CSOM.

  10. Neonatal Orbital Abscess Secondary to Pseudomonas Aeruginosa Conjunctivitis.

    Science.gov (United States)

    Yazici, Bulent; Orucov, Nesimi; Ibrahimzade, Gunay

    Pseudomonas aeruginosa conjunctivitis, although rare in healthy infants, may cause serious ocular and systemic complications. A 30-day-old, otherwise healthy male infant was referred with the diagnosis of right orbital abscess. The patient had been diagnosed as having Pseudomonas conjunctivitis 9 days previously at the referring center. Despite antibiotic treatment, his ocular findings had worsened and marked proptosis had developed. Other examination findings were ptosis, restriction of eye movements, periorbital erythema, and chemosis. Radiologic studies showed a large, homogenous mass with a thick capsule in the lateral retrobulbar orbit. The abscess was drained through a lateral orbitotomy. A culture of the abscess yielded P. aeruginosa. After surgery, the ocular findings improved rapidly without any complication. No other focus of infection or immune system abnormality was found. The patient did not experience any other significant disease during a follow up of 23 months.

  11. Comparative genomic analysis of multiple strains of two unusual plant pathogens: Pseudomonas corrugata and Pseudomonas mediterranea.

    Science.gov (United States)

    Trantas, Emmanouil A; Licciardello, Grazia; Almeida, Nalvo F; Witek, Kamil; Strano, Cinzia P; Duxbury, Zane; Ververidis, Filippos; Goumas, Dimitrios E; Jones, Jonathan D G; Guttman, David S; Catara, Vittoria; Sarris, Panagiotis F

    2015-01-01

    The non-fluorescent pseudomonads, Pseudomonas corrugata (Pcor) and P. mediterranea (Pmed), are closely related species that cause pith necrosis, a disease of tomato that causes severe crop losses. However, they also show strong antagonistic effects against economically important pathogens, demonstrating their potential for utilization as biological control agents. In addition, their metabolic versatility makes them attractive for the production of commercial biomolecules and bioremediation. An extensive comparative genomics study is required to dissect the mechanisms that Pcor and Pmed employ to cause disease, prevent disease caused by other pathogens, and to mine their genomes for genes that encode proteins involved in commercially important chemical pathways. Here, we present the draft genomes of nine Pcor and Pmed strains from different geographical locations. This analysis covered significant genetic heterogeneity and allowed in-depth genomic comparison. All examined strains were able to trigger symptoms in tomato plants but not all induced a hypersensitive-like response in Nicotiana benthamiana. Genome-mining revealed the absence of type III secretion system and known type III effector-encoding genes from all examined Pcor and Pmed strains. The lack of a type III secretion system appears to be unique among the plant pathogenic pseudomonads. Several gene clusters coding for type VI secretion system were detected in all genomes. Genome-mining also revealed the presence of gene clusters for biosynthesis of siderophores, polyketides, non-ribosomal peptides, and hydrogen cyanide. A highly conserved quorum sensing system was detected in all strains, although species specific differences were observed. Our study provides the basis for in-depth investigations regarding the molecular mechanisms underlying virulence strategies in the battle between plants and microbes.

  12. Effects of atmospheric conditions on ice nucleation activity of Pseudomonas

    Directory of Open Access Journals (Sweden)

    C. Glaux

    2012-11-01

    Full Text Available Although ice nuclei from bacterial origin are known to be efficient at the highest temperatures known for ice catalysts, quantitative data are still needed to assess their role in cloud processes. Here we studied the effects of three typical cloud conditions (i acidic pH (ii NO2 and O3 exposure and (iii UV-A exposure on the ice nucleation activity (INA of four Pseudomonas strains. Three of the Pseudomonas syringae strains were isolated from cloud water and the phyllosphere and Pseudomonas fluorescens strain CGina-01 was isolated from Antarctic glacier ice melt. Among the three conditions tested, acidic pH caused the most significant effects on INA likely due to denaturation of the ice nucleation protein complex. Exposure to NO2 and O3 gases had no significant or only weak effects on the INA of two P. syringae strains whereas the INA of P. fluorescens CGina-01 was significantly affected. The INA of the third P. syringae strain showed variable responses to NO2 and O3 exposure. These differences in the INA of different Pseudomonas suggest that the response to atmospheric conditions could be strain-specific. After UV-A exposure, a substantial loss of viability of all four strains was observed whereas their INA decreased only slightly. This corroborates the notion that under certain conditions dead bacterial cells can maintain their INA. Overall, the negative effects of the three environmental factors on INA were more significant at the warmer temperatures. Our results suggest that in clouds where temperatures are near 0 °C, the importance of bacterial ice nucleation in precipitation processes could be reduced by some environmental factors.

  13. Pseudomonas aeruginosa Bloodstream Infection: Importance of Appropriate Initial Antimicrobial Treatment

    OpenAIRE

    Micek, Scott T; Lloyd, Ann E.; David J. Ritchie; Reichley, Richard M.; Fraser, Victoria J.; Kollef, Marin H

    2005-01-01

    Pseudomonas aeruginosa bloodstream infection is a serious infection with significant patient mortality and health-care costs. Nevertheless, the relationship between initial appropriate antimicrobial treatment and clinical outcomes is not well established. This study was a retrospective cohort analysis employing automated patient medical records and the pharmacy database at Barnes-Jewish Hospital. Three hundred five patients with P. aeruginosa bloodstream infection were identified over a 6-yea...

  14. [Genome plasticity and catabolic potential of pseudomonas cepacia]. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    This progress report describes efforts directed at understanding the genomic structure of Pseudomonas cepacia. Variously reported are descriptions of the replicons in the genome, organization of macrorestriction fragments comprising the genome, use of a Tn-5- 751S to insertionally inactivate and map selected genes, construction of IS407 derivatives containing a trimethoprim resistance marker and SwaI site, and analysis of nucleotide sequences of IS401 and IS408.

  15. Complete Genome Sequence of Pseudomonas aeruginosa Phage AAT-1.

    Science.gov (United States)

    Andrade-Domínguez, Andrés; Kolter, Roberto

    2016-08-25

    Aspects of the interaction between phages and animals are of interest and importance for medical applications. Here, we report the genome sequence of the lytic Pseudomonas phage AAT-1, isolated from mammalian serum. AAT-1 is a double-stranded DNA phage, with a genome of 57,599 bp, containing 76 predicted open reading frames. Copyright © 2016 Andrade-Domínguez and Kolter.

  16. Pseudomonas aeruginosa Virulence Analyzed in a Dictyostelium discoideum Host System

    OpenAIRE

    Cosson, Pierre; Zulianello, Laurence; Join-Lambert, Olivier; Faurisson, François; Gebbie, Leigh; Benghezal, Mohammed; Van Delden, Christian; Kocjancic Curty, Lasta; Köhler, Thilo

    2002-01-01

    Pseudomonas aeruginosa is an important opportunistic pathogen that produces a variety of cell-associated and secreted virulence factors. P. aeruginosa infections are difficult to treat effectively because of the rapid emergence of antibiotic-resistant strains. In this study, we analyzed whether the amoeba Dictyostelium discoideum can be used as a simple model system to analyze the virulence of P. aeruginosa strains. The virulent wild-type strain PAO1 was shown to inhibit growth of D. discoide...

  17. [Phlegmonous gastritis. Report of a case induced by Pseudomonas aeruginosa].

    Science.gov (United States)

    Ramos Jiménez, F A; Arocena Cedrón, M G; Goikoetxea Artola, J M; Lázaro Aramburu, S; Múgica Barreiros, P

    1992-06-01

    The authors present a case of phlegmonous gastritis in a 65 year old patient. The diagnosis was made in the operating room and the treatment was conservative; no gastric resection was done. This clinical entity is interesting because it is a least frequent pathology, the pathogenic bacteria which was the cause (Pseudomona aeruginosa) has at this time not been reported in the literature, including the favorable outcome of the patient without gastric resection.

  18. Pyochelin Potentiates the Inhibitory Activity of Gallium on Pseudomonas aeruginosa

    Science.gov (United States)

    Frangipani, Emanuela; Bonchi, Carlo; Minandri, Fabrizia; Imperi, Francesco

    2014-01-01

    Gallium (Ga) is an iron mimetic that has successfully been repurposed for antibacterial chemotherapy. To improve the antibacterial potency of Ga on Pseudomonas aeruginosa, the effect of complexation with a variety of siderophores and synthetic chelators was tested. Ga complexed with the pyochelin siderophore (at a 1:2 ratio) was more efficient than Ga(NO3)3 in inhibiting P. aeruginosa growth, and its activity was dependent on increased Ga entrance into the cell through the pyochelin translocon. PMID:24957826

  19. Recent advances in understanding Pseudomonas aeruginosa as a pathogen

    Science.gov (United States)

    Klockgether, Jens; Tümmler, Burkhard

    2017-01-01

    The versatile and ubiquitous Pseudomonas aeruginosa is an opportunistic pathogen causing acute and chronic infections in predisposed human subjects. Here we review recent progress in understanding P. aeruginosa population biology and virulence, its cyclic di-GMP-mediated switches of lifestyle, and its interaction with the mammalian host as well as the role of the type III and type VI secretion systems in P. aeruginosa infection. PMID:28794863

  20. Cloning and expression of Pseudomonas aeruginosa flagellin in Escherichia coli.

    OpenAIRE

    Kelly-Wintenberg, K; Montie, T. C.

    1989-01-01

    The flagellin gene was isolated from a Pseudomonas aeruginosa PAO1 genomic bank by conjugation into a PA103 Fla- strain. Flagellin DNA was transferred from motile recipient PA103 Fla+ cells by transformation into Escherichia coli. We show that transformed E. coli expresses flagellin protein. Export of flagellin to the E. coli cell surface was suggested by positive colony blots of unlysed cells and by isolation of flagellin protein from E. coli supernatants.

  1. The evolution of a pleiotropic fitness tradeoff in Pseudomonas fluorescens

    OpenAIRE

    MacLean, R. Craig; Bell, Graham; Rainey, Paul B.

    2004-01-01

    The evolution of ecological specialization is expected to carry a cost, due to either antagonistic pleiotropy or mutation accumulation. In general, it has been difficult to distinguish between these two possibilities. Here, we demonstrate that the experimental evolution of niche-specialist genotypes of the bacterium Pseudomonas fluorescens that colonize the air–broth interface of spatially structured microcosms is accompanied by pleiotropic fitness costs in terms of reduced carbon catabolism....

  2. Identification and isolation of insecticidal oxazoles from Pseudomonas spp.

    OpenAIRE

    Grundmann, Florian; Dill, Veronika; Dowling, Andrea; Thanwisai, Aunchalee; Bode, Edna; Chantratita, Narisara; Ffrench-Constant, Richard; Bode, Helge B.

    2012-01-01

    Summary Two new and five known oxazoles were identified from two different Pseudomonas strains in addition to the known pyrones pseudopyronine A and B. Labeling experiments confirmed their structures and gave initial evidence for a novel biosynthesis pathway of these natural oxazoles. In order to confirm their structure, they were synthesized, which also allowed tests of their bioactivity. Additionally, the bioactivities of the synthesis intermediates were also investigated revealing interest...

  3. Antimicrobial effect of probiotic Lactobacillus spp. on Pseudomonas aeruginosa

    OpenAIRE

    Maysaa Kadhim Al-Malkey; Munira Ch. Ismeeal; Fahema Jabbar Abo Al-Hur; Sinaa W. Mohammed; Hanan J. Nayyef

    2017-01-01

    Objectives Study the antimicrobial effect of probiotics produced from Lactobacillus rhamnosus GG and Lactobacillus acidophilus on Pseudomonas aeruginosa isolated from burn and wound infection and their ability of protease production. Methods Swab samples were collected from 70 patients admitted at Burns Center/Al-Yarmouk Teaching Hospital. Primary bacterial identification cultured on differential selective media and biochemical tests were done. The Vitek2 compact system (Biomerieux, France...

  4. A study on nitrogen removal efficiency of Pseudomonas stutzeri ...

    African Journals Online (AJOL)

    By using the nitrogen balance method, the total nitrogen loss was calculated to be 40.1% (w/w) when the carbon source was citric acid with a C/N ratio of 5. Meanwhile, the isolated strain was identified by 16S rDNA to be a Pseudomonas stutzeri with a similarity of 99%. Varying the initial TN, the C/N, the pH value and the ...

  5. Antibacterial compound produced by Pseudomonas aeruginosa strain UICC B-40, an endophytic bacterium isolated from Neesia altissima.

    Science.gov (United States)

    Pratiwi, Rina Hidayati; Hidayat, Iman; Hanafi, Muhammad; Mangunwardoyo, Wibowo

    2017-04-01

    This study's aim was to determine the identity of antibacterial compounds produced by Pseudomonas aeruginosa strain UICC B-40 and describe the antibacterial compounds' mechanisms of action for damaging pathogenic bacteria cells. Isolation and identification of the compounds were carried out using thin layer chromatography (TLC), nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography mass spectrometry (LC-MS) analyses. Antibacterial activity was assayed via minimum inhibitory concentration (MIC) and the antibacterial compound mechanism was observed morphologically through scanning electron microscopy (SEM). This study successfully identified the (2E,5E)-phenyltetradeca-2,5-dienoate antibacterial compound (molecular weight 300 g/mol), composed of a phenolic ester, fatty acid and long chain of aliphatic group structures. MIC values for this compound were determined at 62.5 μg/ml against Staphylococcus aureus strain ATCC 25923. The mechanism of the compound involved breaking down the bacterial cell walls through the lysis process. The (2E,5E)-phenyltetradeca-2,5-dienoate compound exhibited inhibitory activity on the growth of Gram-positive bacteria.

  6. Biomolecular Mechanisms of Pseudomonas aeruginosa and Escherichia coli Biofilm Formation.

    Science.gov (United States)

    Laverty, Garry; Gorman, Sean P; Gilmore, Brendan F

    2014-07-18

    Pseudomonas aeruginosa and Escherichia coli are the most prevalent Gram-negative biofilm forming medical device associated pathogens, particularly with respect to catheter associated urinary tract infections. In a similar manner to Gram-positive bacteria, Gram-negative biofilm formation is fundamentally determined by a series of steps outlined more fully in this review, namely adhesion, cellular aggregation, and the production of an extracellular polymeric matrix. More specifically this review will explore the biosynthesis and role of pili and flagella in Gram-negative adhesion and accumulation on surfaces in Pseudomonas aeruginosa and Escherichia coli. The process of biofilm maturation is compared and contrasted in both species, namely the production of the exopolysaccharides via the polysaccharide synthesis locus (Psl), pellicle Formation (Pel) and alginic acid synthesis in Pseudomonas aeruginosa, and UDP-4-amino-4-deoxy-l-arabinose and colonic acid synthesis in Escherichia coli. An emphasis is placed on the importance of the LuxR homologue sdiA; the luxS/autoinducer-II; an autoinducer-III/epinephrine/norepinephrine and indole mediated Quorum sensing systems in enabling Gram-negative bacteria to adapt to their environments. The majority of Gram-negative biofilms consist of polysaccharides of a simple sugar structure (either homo- or heteropolysaccharides) that provide an optimum environment for the survival and maturation of bacteria, allowing them to display increased resistance to antibiotics and predation.

  7. Biomolecular Mechanisms of Pseudomonas aeruginosa and Escherichia coli Biofilm Formation

    Directory of Open Access Journals (Sweden)

    Garry Laverty

    2014-07-01

    Full Text Available Pseudomonas aeruginosa and Escherichia coli are the most prevalent Gram-negative biofilm forming medical device associated pathogens, particularly with respect to catheter associated urinary tract infections. In a similar manner to Gram-positive bacteria, Gram-negative biofilm formation is fundamentally determined by a series of steps outlined more fully in this review, namely adhesion, cellular aggregation, and the production of an extracellular polymeric matrix. More specifically this review will explore the biosynthesis and role of pili and flagella in Gram-negative adhesion and accumulation on surfaces in Pseudomonas aeruginosa and Escherichia coli. The process of biofilm maturation is compared and contrasted in both species, namely the production of the exopolysaccharides via the polysaccharide synthesis locus (Psl, pellicle Formation (Pel and alginic acid synthesis in Pseudomonas aeruginosa, and UDP-4-amino-4-deoxy-l-arabinose and colonic acid synthesis in Escherichia coli. An emphasis is placed on the importance of the LuxR homologue sdiA; the luxS/autoinducer-II; an autoinducer-III/epinephrine/norepinephrine and indole mediated Quorum sensing systems in enabling Gram-negative bacteria to adapt to their environments. The majority of Gram-negative biofilms consist of polysaccharides of a simple sugar structure (either homo- or heteropolysaccharides that provide an optimum environment for the survival and maturation of bacteria, allowing them to display increased resistance to antibiotics and predation.

  8. Biomolecular Mechanisms of Pseudomonas aeruginosa and Escherichia coli Biofilm Formation

    Science.gov (United States)

    Laverty, Garry; Gorman, Sean P.; Gilmore, Brendan F.

    2014-01-01

    Pseudomonas aeruginosa and Escherichia coli are the most prevalent Gram-negative biofilm forming medical device associated pathogens, particularly with respect to catheter associated urinary tract infections. In a similar manner to Gram-positive bacteria, Gram-negative biofilm formation is fundamentally determined by a series of steps outlined more fully in this review, namely adhesion, cellular aggregation, and the production of an extracellular polymeric matrix. More specifically this review will explore the biosynthesis and role of pili and flagella in Gram-negative adhesion and accumulation on surfaces in Pseudomonas aeruginosa and Escherichia coli. The process of biofilm maturation is compared and contrasted in both species, namely the production of the exopolysaccharides via the polysaccharide synthesis locus (Psl), pellicle Formation (Pel) and alginic acid synthesis in Pseudomonas aeruginosa, and UDP-4-amino-4-deoxy-l-arabinose and colonic acid synthesis in Escherichia coli. An emphasis is placed on the importance of the LuxR homologue sdiA; the luxS/autoinducer-II; an autoinducer-III/epinephrine/norepinephrine and indole mediated Quorum sensing systems in enabling Gram-negative bacteria to adapt to their environments. The majority of Gram-negative biofilms consist of polysaccharides of a simple sugar structure (either homo- or heteropolysaccharides) that provide an optimum environment for the survival and maturation of bacteria, allowing them to display increased resistance to antibiotics and predation. PMID:25438014

  9. Spontaneous Nosocomial Pseudomonas aeruginosa Meningitis Presenting as Trismus

    Directory of Open Access Journals (Sweden)

    C. J. Parr

    2017-01-01

    Full Text Available We describe the case of a 78-year-old female receiving adjuvant postsurgical chemotherapy for colon adenocarcinoma who spontaneously developed nosocomial Pseudomonas meningitis causing severe trismus. The patient was initially admitted for ileus, developing neck stiffness and trismus on the thirteenth day of admission. Cerebrospinal fluid grew pansensitive Pseudomonas aeruginosa. Magnetic resonance imaging of the brain was consistent with bilateral subacute infarcts secondary to meningitis. The patient responded well to 21 days of broad spectrum antimicrobial therapy modified to ceftazidime alone following speciation and sensitivity. Outpatient follow-up at 46 days revealed normal maximal mouth opening with the ability to chew and tolerate a full diet. Trismus is a motor disturbance of the trigeminal nerve with difficulty in opening the mouth. Infectious etiologies commonly described include tetanus, odontogenic infections, or deep neck space infections. This is the first reported case of simultaneous nosocomial Pseudomonas meningitis and trismus in a patient with no history of neurosurgery or lumbar spinal manipulation.

  10. Experimental Pseudomonas aeruginosa mediated rhino sinusitis in mink.

    Science.gov (United States)

    Kirkeby, S; Hammer, A S; Høiby, N; Salomonsen, C M

    2017-05-01

    The nasal and sinus cavities in children may serve as reservoirs for microorganisms that cause recurrent and chronic lung infections. This study evaluates whether the mink can be used as an animal model for studying Pseudomonas aeruginosa mediated rhino-sinusitis since there is no suitable traditional animal model for this disease. Nasal tissue samples from infected and control mink were fixed in formalin, demineralized, and embedded in paraffin. A histological examination of sections from the infected animals revealed disintegration of the respiratory epithelium lining the nasal turbinates and swelling and edema of the submucosa. The expression of mucins and sialylated glycans was examined using immunohistochemistry. MUC1, MUC2 and MUC5AC were upregulated in the inoculated animals as a much stronger staining was present in the respiratory epithelium in the infected animals compared to the controls. The goblet cells in the nasal epithelium from the infected mink showed high affinity to the Maackia amurensis lectin and anti-asialo GM1 indicating a high concentration of α2-3 sialic acid respectively βGalNAc1-4Galβ containing glycans in these mucin producing cells. The nasal cavity in the infected mink shows features of carbohydrate expression comparable to what has been described in the respiratory system after Pseudomonas aeruginosa infection in humans. It is suggested that the mink is suitable for studying Pseudomonas aeruginosa mediated rhino-sinusitis. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  11. Inactivation of Pseudomonas aeruginosa by Chitosan Coated Iron Oxide Nanoparticles.

    Science.gov (United States)

    Mukherjee, Munmun; De, Sirshendu

    2016-01-01

    Pseudomonas aeruginosa is one of the potent opportunistic pathogens associated with respiratory and urinary tract infection. The bacterium owes its pathogenicity due to the intrinsic resistance to antibiotics and disinfectants. The present study is focused on the synthesis of antibacterial chitosan coated iron oxide nanoparticles for rapid inactivation of Pseudomonas aeruginosa. We have discussed the relevant patents on synthesis and antibacterial potential of metallic nanoparticles and chitosan. Chitosan coated iron oxide nanoparticles were synthesized by coprecipitation method at room temperature using non-toxic chitosan and iron salts in alkali media. The particles were characterized and evaluated for antibacterial property against Pseudomonas aeruginosa. The average size of the particles was measured as 52 nm. The surface area of the coated particles was as high as 90 ±5 m2/g. FTIR spectra confirmed the coating of chitosan on nanoparticles. The coated particles showed excellent antibacterial activity against the bacteria. The minimum inhibitory concentration of the coated particles was 105)µg mol-1. The morphological alteration and cytoplasmic leakage of bacteria were confirmed by SEM image and release of intracellular constituents, respectively. Higher 260 nm absorbance value confirmed stronger antibacterial activity of the coated nanoparticles as compared to pure chitosan and bare iron oxide nanoparticles. The study indicated that chitosan coated iron oxide nanoparticles have superior antibacterial property as compared to pure chitosan and iron oxide nanoparticles.

  12. 13C-NMR studies of acetate and methanol metabolism by methylotrophic Pseudomonas strains.

    Science.gov (United States)

    Narbad, A; Hewlins, M J; Callely, A G

    1989-06-01

    The metabolism of [2-13C]acetate by Pseudomonas M27(Icl-) and Pseudomonas MA(Icl+) was studied in vivo using 13C-NMR spectroscopy. The flux of 13C-label into bicarbonate, glutamate and citrate was observed in both organisms. In addition 13C-labelled alpha, alpha-trehalose was synthesized as a major metabolite by Pseudomonas M27 but not by Pseudomonas MA. The presence of this disaccharide in cell extracts of Pseudomonas AM1(Icl-) grown with [13C]methanol was also observed. The data from analysis of the trehalose multiplet signal observed in the spectra of Pseudomonas M27 cell extracts were consistent with the absence of the glyoxylate cycle in this methylotroph.

  13. Effect of green manure on the incidence of cyanogenic Pseudomonas strains in hop garden soils.

    Science.gov (United States)

    Paszkowski, Wojciech L; Dwornikiewicz, Jerzy

    2003-05-01

    Incidence of cyanogenic Pseudomonas strains in hop garden soils in relation to the kind of fertilization was studied. Incidence differed with respect to the fertilization treatment and the age of the plantation. Amendment of soil with rye and with white mustard as green manures limited the number of cyanogenic Pseudomonas strains relative to farmyard manures and NPK fertilization. Among all fertilization treatments, cyanogenic Pseudomonas spp. strains had lowest populations in soils amended with white mustard.

  14. Investigating the diversity of pseudomonas spp. in soil using culture dependent and independent techniques.

    Science.gov (United States)

    Li, Lili; Abu Al-Soud, Waleed; Bergmark, Lasse; Riber, Leise; Hansen, Lars H; Magid, Jakob; Sørensen, Søren J

    2013-10-01

    Less than 1 % of bacterial populations present in environmental samples are culturable, meaning that cultivation will lead to an underestimation of total cell counts and total diversity. However, it is less clear whether this is also true for specific well-defined groups of bacteria for which selective culture media is available. In this study, we use culture dependent and independent techniques to describe whether isolation of Pseudomonas spp. on selective nutrient-poor NAA 1:100 agar-medium can reflect the full diversity, found by pyrosequencing, of the total soil Pseudomonas community in an urban waste field trial experiment. Approximately 3,600 bacterial colonies were isolated using nutrient-poor NAA 1:100 medium from soils treated with different fertilizers; (i) high N-level sewage sludge (SA), (ii) high N-level cattle manure (CMA), and (iii) unfertilized control soil (U). Based on Pseudomonas specific quantitative-PCR and Pseudomonas CFU counts, less than 4 % of Pseudomonas spp. were culturable using NAA 1:100 medium. The Pseudomonas selectivity and specificity of the culture medium were evaluated by 454 pyrosequencing of 16S rRNA gene amplicons generated using Bacteria- and Pseudomonas-specific primers. Pyrosequencing results showed that most isolates were Pseudomonas and that the culturable fraction of Pseudomonas spp. reflects most clusters of the total Pseudomonas diversity in soil. This indicates that NAA 1:100 medium is highly selective for Pseudomonas species, and reveals the ability of NAA 1:100 medium to culture mostly the dominant Pseudomonas species in soil.

  15. Measurement of the electron structure function F2e at LEP energies

    Science.gov (United States)

    Abdallah, J.; Abreu, P.; Adam, W.; Adzic, P.; Albrecht, T.; Alemany-Fernandez, R.; Allmendinger, T.; Allport, P. P.; Amaldi, U.; Amapane, N.; Amato, S.; Anashkin, E.; Andreazza, A.; Andringa, S.; Anjos, N.; Antilogus, P.; Apel, W.-D.; Arnoud, Y.; Ask, S.; Asman, B.; Augustin, J. E.; Augustinus, A.; Baillon, P.; Ballestrero, A.; Bambade, P.; Barbier, R.; Bardin, D.; Barker, G. J.; Baroncelli, A.; Battaglia, M.; Baubillier, M.; Becks, K.-H.; Begalli, M.; Behrmann, A.; Belous, K.; Ben-Haim, E.; Benekos, N.; Benvenuti, A.; Berat, C.; Berggren, M.; Bertrand, D.; Besancon, M.; Besson, N.; Bloch, D.; Blom, M.; Bluj, M.; Bonesini, M.; Boonekamp, M.; Booth, P. S. L.; Borisov, G.; Botner, O.; Bouquet, B.; Bowcock, T. J. V.; Boyko, I.; Bracko, M.; Brenner, R.; Brodet, E.; Bruckman, P.; Brunet, J. M.; Buschbeck, B.; Buschmann, P.; Calvi, M.; Camporesi, T.; Canale, V.; Carena, F.; Castro, N.; Cavallo, F.; Chapkin, M.; Charpentier, Ph.; Checchia, P.; Chierici, R.; Chliapnikov, P.; Chudoba, J.; Chung, S. U.; Cieslik, K.; Collins, P.; Contri, R.; Cosme, G.; Cossutti, F.; Costa, M. J.; Crennell, D.; Cuevas, J.; D'Hondt, J.; da Silva, T.; Da Silva, W.; Della Ricca, G.; De Angelis, A.; De Boer, W.; De Clercq, C.; De Lotto, B.; De Maria, N.; De Min, A.; de Paula, L.; Di Ciaccio, L.; Di Simone, A.; Doroba, K.; Drees, J.; Eigen, G.; Ekelof, T.; Ellert, M.; Elsing, M.; Espirito Santo, M. C.; Fanourakis, G.; Fassouliotis, D.; Feindt, M.; Fernandez, J.; Ferrer, A.; Ferro, F.; Flagmeyer, U.; Foeth, H.; Fokitis, E.; Fulda-Quenzer, F.; Fuster, J.; Gandelman, M.; Garcia, C.; Gavillet, Ph.; Gazis, E.; Gokieli, R.; Golob, B.; Gomez-Ceballos, G.; Gonçalves, P.; Graziani, E.; Grosdidier, G.; Grzelak, K.; Guy, J.; Haag, C.; Hallgren, A.; Hamacher, K.; Hamilton, K.; Haug, S.; Hauler, F.; Hedberg, V.; Hennecke, M.; Hoffman, J.; Holmgren, S.-O.; Holt, P. J.; Houlden, M. A.; Jackson, J. N.; Jarlskog, G.; Jarry, P.; Jeans, D.; Johansson, E. K.; Jonsson, P.; Joram, C.; Jungermann, L.; Kapusta, F.; Katsanevas, S.; Katsoufis, E.; Kernel, G.; Kersevan, B. P.; Kerzel, U.; King, B. T.; Kjaer, N. J.; Kluit, P.; Kokkinias, P.; Kourkoumelis, C.; Kouznetsov, O.; Krumstein, Z.; Kucharczyk, M.; Lamsa, J.; Leder, G.; Ledroit, F.; Leinonen, L.; Leitner, R.; Lemonne, J.; Lepeltier, V.; Lesiak, T.; Liebig, W.; Liko, D.; Lipniacka, A.; Lopes, J. H.; Lopez, J. M.; Loukas, D.; Lutz, P.; Lyons, L.; MacNaughton, J.; Malek, A.; Maltezos, S.; Mandl, F.; Marco, J.; Marco, R.; Marechal, B.; Margoni, M.; Marin, J.-C.; Mariotti, C.; Markou, A.; Martinez-Rivero, C.; Masik, J.; Mastroyiannopoulos, N.; Matorras, F.; Matteuzzi, C.; Mazzucato, F.; Mazzucato, M.; Mc Nulty, R.; Meroni, C.; Migliore, E.; Mitaroff, W.; Mjoernmark, U.; Moa, T.; Moch, M.; Moenig, K.; Monge, R.; Montenegro, J.; Moraes, D.; Moreno, S.; Morettini, P.; Mueller, U.; Muenich, K.; Mulders, M.; Mundim, L.; Murray, W.; Muryn, B.; Myatt, G.; Myklebust, T.; Nassiakou, M.; Navarria, F.; Nawrocki, K.; Nemecek, S.; Nicolaidou, R.; Nikolenko, M.; Oblakowska-Mucha, A.; Obraztsov, V.; Olshevski, A.; Onofre, A.; Orava, R.; Osterberg, K.; Ouraou, A.; Oyanguren, A.; Paganoni, M.; Paiano, S.; Palacios, J. P.; Palka, H.; Papadopoulou, Th. D.; Pape, L.; Parkes, C.; Parodi, F.; Parzefall, U.; Passeri, A.; Passon, O.; Peralta, L.; Perepelitsa, V.; Perrotta, A.; Petrolini, A.; Piedra, J.; Pieri, L.; Pierre, F.; Pimenta, M.; Piotto, E.; Podobnik, T.; Poireau, V.; Pol, M. E.; Polok, G.; Pozdniakov, V.; Pukhaeva, N.; Pullia, A.; Radojicic, D.; Rebecchi, P.; Rehn, J.; Reid, D.; Reinhardt, R.; Renton, P.; Richard, F.; Ridky, J.; Rivero, M.; Rodriguez, D.; Romero, A.; Ronchese, P.; Roudeau, P.; Rovelli, T.; Ruhlmann-Kleider, V.; Ryabtchikov, D.; Sadovsky, A.; Salmi, L.; Salt, J.; Sander, C.; Savoy-Navarro, A.; Schwickerath, U.; Sekulin, R.; Siebel, M.; Sisakian, A.; Slominski, W.; Smadja, G.; Smirnova, O.; Sokolov, A.; Sopczak, A.; Sosnowski, R.; Spassov, T.; Stanitzki, M.; Stocchi, A.; Strauss, J.; Stugu, B.; Szczekowski, M.; Szeptycka, M.; Szumlak, T.; Szwed, J.; Tabarelli, T.; Tegenfeldt, F.; Timmermans, J.; Tkatchev, L.; Tobin, M.; Todorovova, S.; Tomé, B.; Tonazzo, A.; Tortosa, P.; Travnicek, P.; Treille, D.; Tristram, G.; Trochimczuk, M.; Troncon, C.; Turluer, M.-L.; Tyapkin, I. A.; Tyapkin, P.; Tzamarias, S.; Uvarov, V.; Valenti, G.; Van Dam, P.; Van Eldik, J.; van Remortel, N.; Van Vulpen, I.; Vegni, G.; Veloso, F.; Venus, W.; Verdier, P.; Verzi, V.; Vilanova, D.; Vitale, L.; Vrba, V.; Wahlen, H.; Washbrook, A. J.; Weiser, C.; Wicke, D.; Wickens, J.; Wilkinson, G.; Winter, M.; Witek, M.; Yushchenko, O.; Zalewska, A.; Zalewski, P.; Zavrtanik, D.; Zhuravlov, V.; Zimin, N. I.; Zintchenko, A.; Zupan, M.

    2014-10-01

    The hadronic part of the electron structure function F2e has been measured for the first time, using e+e- data collected by the DELPHI experiment at LEP, at centre-of-mass energies of √{ s} = 91.2- 209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F2e data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F2γ analyses and help in refining existing parameterisations.

  16. Expert advisor for the QUAL2E water-quality model

    Energy Technology Data Exchange (ETDEWEB)

    Barnwell, T.O.; Brown, L.C.; Marek, W.

    1987-12-01

    Computer modeling is becoming an integral part of decision making in water-pollution control. Problems increasingly involve complex interactions among elements of the environment and large, multi-media modeling systems must be built to understand these interactions. Expert systems is an innovative methodology that can assist in building, using, and interpreting the output of these models. The paper reviews the use and evaluates the potential of expert systems technology in environmental modeling and describes elements of an expert advisor for the stream water-quality model QUAL2E. QUAL2E has a long history of use both in the United States and worldwide and is a proven, effective modeling tool for analyzing the dissolved oxygen balance in a stream or river. Because of the widespread usage, a body of experience and empirical knowledge about the computer program has been gained that is ideal for codification in an expert system.

  17. Quality Assurance on a Custom SiPMs Array for the Mu2e Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Atanov, N.; et al.

    2017-11-20

    The Mu2e experiment at Fermilab will search for the coherent $\\mu \\to e$ conversion on aluminum atoms. The detector system consists of a straw tube tracker and a crystal calorimeter. A pre-production of 150 Silicon Photomultiplier arrays for the Mu2e calorimeter has been procured. A detailed quality assur- ance has been carried out on each SiPM for the determination of its own operation voltage, gain, dark current and PDE. The measurement of the mean-time-to-failure for a small random sample of the pro-production group has been also completed as well as the determination of the dark current increase as a function of the ioninizing and non-ioninizing dose.

  18. Measurement of the electron structure function F2e at LEP energies

    Directory of Open Access Journals (Sweden)

    J. Abdallah

    2014-10-01

    Full Text Available The hadronic part of the electron structure function F2e has been measured for the first time, using e+e− data collected by the DELPHI experiment at LEP, at centre-of-mass energies of s=91.2–209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F2e data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F2γ analyses and help in refining existing parameterisations.

  19. Final Technical Report: Mu2e at the City University of New York

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, Kevin [City Univ. (CUNY), NY (United States); Popp, James [City Univ. (CUNY), NY (United States)

    2017-06-25

    This DOE grant award for was for the period June 1, 2013 to March 31, 2016. Popp was awarded an internship in the Visiting Faculty Program at FNAL in summer of 2015; consequently the unused portion of summer salary funds allowed us to apply for a no-cost extension with our remaining funds until March 31, 2017. That support furnished us with the means to carry out numerous successful projects for Mu2e for nearly four years. Up to now, the driving force to our work has been dictated primarily by the Mu2e Project cost and schedule needs. Our work has been under the purview of three of the Working Groups to which we belong: Target Station, Electron Tracker, and Stopping Target Monitor. We have carried out a mix of bench-top testing tasks locally, more elaborate work at Fermilab every summer, and extensive software development and simulation studies.

  20. Pseudomonas aeruginosa exotoxin A-induced hepatotoxicity in dynamics: an animal model in white mice

    National Research Council Canada - National Science Library

    Morrison A.V; Popovich V.I; Morrison V.V

    2015-01-01

    .... Material and Methods. The experiments were carried out on white mice in dynamics development of pseudomonas aeruginosa caused by intraperitoneal injection of various dosage of exotoxin A. Results...

  1. Compromised Host Defense on Pseudomonas aeruginosa Biofilms: Characterization of Neutrophil and Biofilm Interactions

    National Research Council Canada - National Science Library

    Jesaitis, Algirdas J; Franklin, Michael J; Berglund, Deborah; Sasaki, Maiko; Lord, Connie I; Bleazard, Justin B; Duffy, James E; Beyenal, Haluk; Lewandowski, Zbigniew

    2003-01-01

    Departments of * Microbiology, Civil Engineering, Chemical Engineering, and Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717 Pseudomonas aeruginosa is an opportunistic pathogen that forms...

  2. Combined inoculation of Pseudomonas fluorescens and Trichoderma harzianum for enhancing plant growth of vanilla (Vanilla planifolia)

    National Research Council Canada - National Science Library

    Sandheep, A R; Asok, A K; Jisha, M S

    2013-01-01

    .... Based on the in vitro performance of indigenous Trichoderma spp. and Pseudomonas spp., four effective antagonists were selected and screened under greenhouse experiment for their growth enhancement potential...

  3. Combined inoculation of Pseudomonas fluorescens and Trichoderma harzianum for enhancing plant growth of vanilla (Vanilla planifolia).

    Science.gov (United States)

    Sandheep, A R; Asok, A K; Jisha, M S

    2013-06-15

    This study was conducted to evaluate the plant growth promoting efficiency of combined inoculation of rhizobacteria on Vanilla plants. Based on the in vitro performance of indigenous Trichoderma spp. and Pseudomonas spp., four effective antagonists were selected and screened under greenhouse experiment for their growth enhancement potential. The maximum percentage of growth enhancement were observed in the combination of Trichoderma harzianum with Pseudomonas fluorescens treatment followed by Pseudomonas fluorescens, Trichoderma harzianum, Pseudomonas putida and Trichoderma virens, respectively in decreasing order. Combined inoculation of Trichoderma harzianum and Pseudomonas fluorescens registered the maximum length of vine (82.88 cm), highest number of leaves (26.67/plant), recorded the highest fresh weight of shoots (61.54 g plant(-1)), fresh weight of roots (4.46 g plant(-1)) and dry weight of shoot (4.56 g plant(-1)) where as the highest dry weight of roots (2.0806 g plant(-1)) were achieved with treatments of Pseudomonas fluorescens. Among the inoculated strains, combined inoculation of Trichoderma harzianum and Pseudomonas fluorescens recorded the maximum nitrogen uptake (61.28 mg plant(-1)) followed by the combined inoculation of Trichoderma harzianum (std) and Pseudomonas fluorescens (std) (55.03 mg plant(-1)) and the highest phosphorus uptake (38.80 mg plant(-1)) was recorded in dual inoculation of Trichoderma harzianum and Pseudomonas fluorescens.

  4. Epitope Mapping of Avian Influenza M2e Protein: Different Species Recognise Various Epitopes.

    Science.gov (United States)

    Hasan, Noor Haliza; Ebrahimie, Esmaeil; Ignjatovic, Jagoda; Tarigan, Simson; Peaston, Anne; Hemmatzadeh, Farhid

    2016-01-01

    A common approach for developing diagnostic tests for influenza virus detection is the use of mouse or rabbit monoclonal and/or polyclonal antibodies against a target antigen of the virus. However, comparative mapping of the target antigen using antibodies from different animal sources has not been evaluated before. This is important because identification of antigenic determinants of the target antigen in different species plays a central role to ensure the efficiency of a diagnostic test, such as competitive ELISA or immunohistochemistry-based tests. Interest in the matrix 2 ectodomain (M2e) protein of avian influenza virus (AIV) as a candidate for a universal vaccine and also as a marker for detection of virus infection in vaccinated animals (DIVA) is the rationale for the selection of this protein for comparative mapping evaluation. This study aimed to map the epitopes of the M2e protein of avian influenza virus H5N1 using chicken, mouse and rabbit monoclonal or monospecific antibodies. Our findings revealed that rabbit antibodies (rAbs) recognized epitope 6EVETPTRN13 of the M2e, located at the N-terminal of the protein, while mouse (mAb) and chicken antibodies (cAbs) recognized epitope 10PTRNEWECK18, located at the centre region of the protein. The findings highlighted the difference between the M2e antigenic determinants recognized by different species that emphasized the importance of comparative mapping of antibody reactivity from different animals to the same antigen, especially in the case of multi-host infectious agents such as influenza. The findings are of importance for antigenic mapping, as well as diagnostic test and vaccine development.

  5. Negatively cooperative binding properties of human cytochrome P450 2E1 with monocyclic substrates.

    Science.gov (United States)

    Ping, Jie; Wang, Ya-Jun; Wang, Jing-Fang; Li, Xuan; Li, Yi-Xue; Hao, Pei

    2012-09-01

    Human CYP2E1 accounts for almost 2% of total CYP enzymes in the liver cells, and plays a crucial role in the metabolism of small molecular weight compounds. This enzyme is associated with the nearly 6% metabolisms of the currently clinical drugs. However, it is found that CYP2E1 has a non-hyperbolic kinetic profile that can not be explained by the common Michaelis-Menten mechanism. Further studies show that the non-hyperbolic kinetic behaviors are associated with multiple substrate binding, which is also known as the cooperative binding properties. However, the detailed mechanism for the cooperative binding is not clear by now. In this paper, we summarized the experimental and theoretical studies on the cooperative binding mechanism. Based on the structural analysis, a second substrate binding site is confirmed in human CYP2E1, which is located neither in the region near Leu103, Leu210 and Phe478, nor far from the active site. Additionally, two important residues Thr303 and Phe478 are also identified to be the key factors in the cooperative binding on the short-range and long-range effects, respectively. The former plays a crucial role in the positioning of substrates and in proton delivery to the active site; the latter is located between the substrate access channel and the active site, and exhibits directly effects on substrate access or on substrate positioning in the active site. All these points can provide useful information for the cooperative binding in human CYP2E1, revealing the detailed mechanism for the non-hyperbolic kinetic behaviors.

  6. Mouse Spermatocytes Express CYP2E1 and Respond to Acrylamide Exposure

    Science.gov (United States)

    Nixon, Belinda J.; Katen, Aimee L.; Stanger, Simone J.; Schjenken, John E.; Nixon, Brett; Roman, Shaun D.

    2014-01-01

    Metabolism of xenobiotics by cytochrome P450s (encoded by the CYP genes) often leads to bio-activation, producing reactive metabolites that interfere with cellular processes and cause DNA damage. In the testes, DNA damage induced by xenobiotics has been associated with impaired spermatogenesis and adverse effects on reproductive health. We previously reported that chronic exposure to the reproductive toxicant, acrylamide, produced high levels of DNA damage in spermatocytes of Swiss mice. CYP2E1 metabolises acrylamide to glycidamide, which, unlike acrylamide, readily forms adducts with DNA. Thus, to investigate the mechanisms of acrylamide toxicity in mouse male germ cells, we examined the expression of the CYP, CYP2E1, which metabolises acrylamide. Using Q-PCR and immunohistochemistry, we establish that CYP2E1 is expressed in germ cells, in particular in spermatocytes. Additionally, CYP2E1 gene expression was upregulated in these cells following in vitro acrylamide exposure (1 µM, 18 h). Spermatocytes were isolated and treated with 1 µM acrylamide or 0.5 µM glycidamide for 18 hours and the presence of DNA-adducts was investigated using the comet assay, modified to detect DNA-adducts. Both compounds produced significant levels of DNA damage in spermatocytes, with a greater response observed following glycidamide exposure. A modified comet assay indicated that direct adduction of DNA by glycidamide was a major source of DNA damage. Oxidative stress played a small role in eliciting this damage, as a relatively modest effect was found in a comet assay modified to detect oxidative adducts following glycidamide exposure, and glutathione levels remained unchanged following treatment with either compound. Our results indicate that the male germ line has the capacity to respond to xenobiotic exposure by inducing detoxifying enzymes, and the DNA damage elicited by acrylamide in male germ cells is likely due to the formation of glycidamide adducts. PMID:24788432

  7. Measurement of the electron structure function F2e at LEP energies

    NARCIS (Netherlands)

    Abdallah, J.; et al., [Unknown; van Vulpen, I.

    2014-01-01

    The hadronic part of the electron structure function F2e has been measured for the first time, using e+e−e+e− data collected by the DELPHI experiment at LEP, at centre-of-mass energies of √s=91.2-209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function.

  8. Comparison of chlorzoxazone one-sample methods to estimate CYP2E1 activity in humans

    DEFF Research Database (Denmark)

    Kramer, Iza; Dalhoff, Kim; Clemmesen, Jens O

    2003-01-01

    OBJECTIVE: Comparison of a one-sample with a multi-sample method (the metabolic fractional clearance) to estimate CYP2E1 activity in humans. METHODS: Healthy, male Caucasians ( n=19) were included. The multi-sample fractional clearance (Cl(fe)) of chlorzoxazone was compared with one-time-point cl......OBJECTIVE: Comparison of a one-sample with a multi-sample method (the metabolic fractional clearance) to estimate CYP2E1 activity in humans. METHODS: Healthy, male Caucasians ( n=19) were included. The multi-sample fractional clearance (Cl(fe)) of chlorzoxazone was compared with one......-time-point clearance estimation (Cl(est)) at 3, 4, 5 and 6 h. Furthermore, the metabolite/drug ratios (MRs) estimated from one-time-point samples at 1, 2, 3, 4, 5 and 6 h were compared with Cl(fe). RESULTS: The concordance between Cl(est) and Cl(fe) was highest at 6 h. The minimal mean prediction error (MPE) of Cl......-dose-sample estimates, Cl(est) at 3 h or 6 h, and MR at 3 h, can serve as reliable markers of CYP2E1 activity. The one-sample clearance method is an accurate, renal function-independent measure of the intrinsic activity; it is simple to use and easily applicable to humans....

  9. Enzymatic degradation of A2E, a retinal pigment epithelial lipofuscin bisretinoid.

    Science.gov (United States)

    Wu, Yalin; Zhou, Jilin; Fishkin, Nathan; Rittmann, Bruce E; Sparrow, Janet R

    2011-02-02

    Some forms of blinding macular disease are associated with excessive accumulation of bisretinoid lipofuscin in retinal pigment epithelial (RPE) cells of the eye. This material is refractory to lysosomal enzyme degradation. In addition to gene and drug-based therapies, treatments that reverse the accumulation of bisretinoid would be beneficial. Thus, we have examined the feasibility of degrading the bisretinoids by delivery of exogenous enzyme. As proof of principle we report that horseradish peroxidase (HRP) can cleave the RPE bisretinoid A2E. In both cell-free and cell-based assays, A2E levels were decreased in the presence of HRP. HRP-associated cleavage products were detected by ultraperformance liquid chromatography (UPLC) coupled to electrospray ionization mass spectrometry, and the structures of the aldehyde-bearing cleavage products were elucidated by 18O-labeling and 1H NMR spectroscopy and by recording UV−vis absorbance spectra. These findings indicate that RPE bisretinoids such as A2E can be degraded by appropriate enzyme activities.

  10. W2E--Wellness Warehouse Engine for Semantic Interoperability of Consumer Health Data.

    Science.gov (United States)

    Honko, Harri; Andalibi, Vafa; Aaltonen, Timo; Parak, Jakub; Saaranen, Mika; Viik, Jari; Korhonen, Ilkka

    2016-11-01

    Novel health monitoring devices and applications allow consumers easy and ubiquitous ways to monitor their health status. However, technologies from different providers lack both technical and semantic interoperability and hence the resulting health data are often deeply tied to a specific service, which is limiting its reusability and utilization in different services. We have designed a Wellness Warehouse Engine (W2E) that bridges this gap and enables seamless exchange of data between different services. W2E provides interfaces to various data sources and makes data available via unified representational state transfer application programming interface to other services. Importantly, it includes Unifier--an engine that allows transforming input data into generic units reusable by other services, and Analyzer--an engine that allows advanced analysis of input data, such as combining different data sources into new output parameters. In this paper, we describe the architecture of W2E and demonstrate its applicability by using it for unifying data from four consumer activity trackers, using a test base of 20 subjects each carrying out three different tracking sessions. Finally, we discuss challenges of building a scalable Unifier engine for the ever-enlarging number of new devices.

  11. Effects of nicotine on cytochrome P450 2A6 and 2E1 activities

    Science.gov (United States)

    Hukkanen, Janne; Jacob, Peyton; Peng, Margaret; Dempsey, Delia; Benowitz, Neal L

    2010-01-01

    AIMS Smoking slows the metabolism of nicotine and accelerates the metabolism of chlorzoxazone, which are probe reactions for cytochrome P450 2A6 (CYP2A6) and CYP2E1 activities, respectively. We aimed to determine the role of nicotine in these metabolic effects of cigarette smoking. METHODS The study had a single-blind, randomized, crossover two-arm design. Twelve healthy smokers were given two transdermal patches with 42-mg nicotine a day or placebo patches, each for 10 days. The subjects abstained from smoking during the study arms. Oral chlorzoxazone was given on day 7 and deuterium-labelled nicotine-d2 and cotinine-d4 infusion on day 8. RESULTS There was no significant influence of transdermal nicotine administration on pharmacokinetic parameters of nicotine-d2 or on the formation of cotinine-d2. Nicotine decreased the volume of distribution (62.6 vs. 67.7 l, 95% confidence interval of the difference −9.7, −0.6, P= 0.047) of infused cotinine-d4. There were no significant differences in disposition kinetics of chlorzoxazone between the treatments. CONCLUSIONS CYP2A6 and CYP2E1 activities are not affected by nicotine. The tobacco smoke constituents responsible for the reduced CYP2A6 and increased CYP2E1 activities remain unknown. PMID:20233178

  12. In vivo and in vitro characterization of CYP2E1 activity in Japanese and Caucasians.

    Science.gov (United States)

    Kim, R B; Yamazaki, H; Chiba, K; O'Shea, D; Mimura, M; Guengerich, F P; Ishizaki, T; Shimada, T; Wilkinson, G R

    1996-10-01

    Chlorzoxazone's disposition after oral administration was determined in 20 young healthy Caucasian men and a similar group of Japanese men. The drug's plasma concentrations were significantly higher and its rate of elimination slower in Japanese compared to Caucasian men. Accordingly, chlorzoxazone's oral clearance was smaller (40%) in Japanese men and a similar difference (30%) was still apparent after normalizing for body weight (3.74 +/- 1.23 versus 5.05 +/- 1.41 ml.min-1.kg-1, P relationships were found between measures of CYP2E1 activity, both in vivo and in vitro, and genomic polymorphisms in the CYP2E1 gene identified by Rsal/Pstl and Dral restriction fragment length polymorphisms. Collectively, these data show an interracial difference in CYP2E1 activity. Because this enzyme is importantly involved in the activation of environmental procarcinogens, such a difference may account, in part, for the lower rate of some cancers, e.g., lung cancer, in Japanese compared to Caucasians men.

  13. One-Dimensional Stacking of Bifunctional Dithia- and Diselenadiazolyl Radicals : Preparation and Structural and Electronic Properties of 1,3-[(E2N2C)C6H4(CN2E2)] (E = S, Se)

    NARCIS (Netherlands)

    Andrews, M.P.; Douglass, D.C.; Fleming, R.M.; Glarum, S.H.; Haddon, R.C.; Marsh, P.; Oakley, R.T.; Palstra, T.T.M.; Schneemeyer, L.F.; Trucks, G.W.; Tycko, R.; Waszczak, J.V.; Young, K.M.; Zimmerman, N.M.; Cordes, A.W.

    1991-01-01

    The preparation and solid-state characterization of the 1,3-phenylene-bridged bis(dithiadiazolyl) and bis(diselenadiazolyl) diradicals 1,3-[(E2N2C)C6H4(CN2E2)] (E = S, Se) are reported. The isomorphous crystals of 1,3-[(E2N2C)C6H4(CN2E2)] so obtained are tetragonal, space group I41/a. Stacks of

  14. De aanwezigheid van Pseudomonas aeruginosa in circulatiebaden in relatie tot de controle volgens de Wet Hygiene en Veiligheid Zwemgelegenheden

    NARCIS (Netherlands)

    Schijven JF; Havelaar AH

    1989-01-01

    Door 8 externe laboratoria werden 133 buitenbaden en 340 binnenbaden onderzocht op aanwezigheid van Pseudomonas aeruginosa. Het betrof circulatiebaden, die periodiek volgens de eisen van het Besluit Hygiene en Veiligheid Zwemgelegenheden (BHVZ) werden gecontroleerd. Pseudomonas aeruginosa bleek

  15. Ethanol Induction of CYP2A5: Role of CYP2E1-ROS-Nrf2 Pathway

    Science.gov (United States)

    Lu, Yongke; Zhang, Xu Hannah

    2012-01-01

    Chronic ethanol consumption was previously shown to induce CYP2A5 in mice, and this induction of CYP2A5 by ethanol was CYP2E1 dependent. In this study, the mechanisms of CYP2E1-dependent ethanol induction of CYP2A5 were investigated. CYP2E1 was induced by chronic ethanol consumption to the same degree in wild-type (WT) mice and CYP2A5 knockout (Cyp2a5 –/–) mice, suggesting that unlike the CYP2E1-dependent ethanol induction of CYP2A5, ethanol induction of CYP2E1 is not CYP2A5 dependent. Microsomal ethanol oxidation was about 25% lower in Cyp2a5 –/– mice compared with that in WT mice, suggesting that CYP2A5 can oxidize ethanol although to a lesser extent than CYP2E1 does. CYP2A5 was induced by short-term ethanol consumption in human CYP2E1 transgenic knockin (Cyp2e1 –/– KI) mice but not in CYP2E1 knockout (Cyp2e1 –/–) mice. The redox-sensitive transcription factor nuclear factor-erythroid 2-related factor 2 (Nrf2) was also induced by acute ethanol in Cyp2e1 –/– KI mice but not in Cyp2e1 –/– mice. Ethanol induction of CYP2A5 in Nrf2 knockout (Nrf2 –/–) mice was lower compared with that in WT mice, whereas CYP2E1 induction by ethanol was comparable in WT and Nrf2 –/– mice. Antioxidants (N-acetyl-cysteine and vitamin C), which blocked oxidative stress induced by chronic ethanol in WT mice and acute ethanol in Cyp2e1 –/– KI mice, also blunted the induction of CYP2A5 and Nrf2 by ethanol but not the induction of CYP2E1 by ethanol. These results suggest that oxidative stress induced by ethanol via induction of CYP2E1 upregulates Nrf2 activity, which in turn regulates ethanol induction of CYP2A5. Results obtained from primary hepatocytes, mice gavaged with binge ethanol or fed chronic ethanol, show that Nrf2-regulated ethanol induction of CYP2A5 protects against ethanol-induced steatosis. PMID:22552773

  16. Blue light induced A2E oxidation in rat eyes--experimental animal model of dry AMD.

    Science.gov (United States)

    Wielgus, A R; Collier, R J; Martin, E; Lih, F B; Tomer, K B; Chignell, C F; Roberts, J E

    2010-11-01

    Previous studies have shown that short-wavelength blue visible light induces retinal injury and may be a risk factor for age related macular degeneration. A2E is a blue light absorbing retinal chromophore that accumulates with age. Our previous in vitro studies have determined that, although A2E itself has a low phototoxic efficiency, the oxidation products of A2E that are formed in the presence of visible light can contribute to observed retinal pigment epithelial photodamage. The purpose of this study was to investigate the effects of blue light on retinal phototoxicity and its relationship to A2E, oxidized A2E and its isomers. Sprague-Dawley albino rats were dark adapted for 24 h. Control rats remained in the dark while experimental rats were exposed to blue light (λ = 450 nm, 3.1 mW cm(-2)) for 6 h. Isolated retinas were homogenized in Folch extraction mixture and then in chloroform. The dried extracts were reconstituted and divided for determination of organic soluble compound. Esters of fatty acids were determined with GC-MS, A2E and other chromophores using HPLC, and A2E oxidation products with LC-MS. Exposure of rat eyes to blue light did not significantly change the fatty acid composition of the retina. The A2E concentration (normalized to fatty acid content) in blue light exposed animals was found to be lower than the A2E concentration in control rats. The concentrations of all-trans-retinal-ethanolamine adduct and iso-A2E a precursor and an isomer of A2E respectively, were also lower after blue-light exposure than in the retinas of rats housed in the dark. On the other hand, the amount of oxidized forms of A2E was higher in the animals exposed to blue light. We conclude that in the rat eye, blue-light exposure promotes oxidation of A2E and iso-A2E to the products that are toxic to retinal tissue. Although high concentrations of A2E may be cytotoxic to the retina, the phototoxicity associated with blue light damage to the retina is in part a result of

  17. Polytrauma Increases Susceptibility to Pseudomonas Pneumonia in Mature Mice.

    Science.gov (United States)

    Turnbull, Isaiah R; Ghosh, Sarbani; Fuchs, Anja; Hilliard, Julia; Davis, Christopher G; Bochicchio, Grant V; Southard, Robert E

    2016-05-01

    Pneumonia is the most common complication observed in patients with severe injuries. Although the average age of injured patients is 47 years, existing studies of the effect of injury on the susceptibility to infectious complications have focused on young animals, equivalent to a late adolescent human. We hypothesized that mature adult animals are more susceptible to infection after injury than younger counterparts. To test this hypothesis, we challenged 6 to 8-month-old mature mice to a polytrauma injury followed by Pseudomonas aeruginosa pneumonia and compared them to young (8-10-week-old) animals. We demonstrate that polytrauma injury increases mortality from pneumonia in mature animals (sham-pneumonia 21% vs. polytrauma-pneumonia 62%) but not younger counterparts. After polytrauma, pneumonia in mature mice is associated with higher bacterial burden in lung, increased incidence of bacteremia, and elevated levels of bacteria in the blood, demonstrating that injury decreases the ability to control the infectious challenge. We further find that polytrauma did not induce elevations in circulating cytokine levels (TNF-alpha, IL-6, KC, and IL-10) 24  h after injury. However, mature mice subjected to polytrauma demonstrated an exaggerated circulating inflammatory cytokine response to subsequent Pseudomonas pneumonia. Additionally, whereas prior injury increases LPS-stimulated IL-6 production by peripheral blood leukocytes from young (8-10-week-old) mice, injury does not prime IL-6 production by cell from mature adult mice. We conclude that in mature mice polytrauma results in increased susceptibility to Pseudomonas pneumonia while priming an exaggerated but ineffective inflammatory response.

  18. Pseudomonas turukhanskensis sp. nov., isolated from oil-contaminated soils.

    Science.gov (United States)

    Korshunova, Tatiana Y; Ramírez-Bahena, Martha-Helena; Chetverikov, Sergey P; Igual, Jose M; Peix, Álvaro; Loginov, Oleg

    2016-11-01

    A bacterial strain named IB1.1T was isolated in a screening of hydrocarbon-degrading bacteria from oil-contaminated soils on the territory of the Turukhansk District of Krasnoyarsk Krai, East Siberia, Russia. The 16S rRNA gene sequence had 98.7 % identity with respect to the closest phylogenetic relative, Pseudomonas granadensis F-278,770T, and the next most closely related species with 98.6 % similarity was Pseudomonaspunonensis, suggesting that IB1.1T should be classified within the genus Pseudomonas. The analysis of housekeeping genes rpoB, rpoD and gyrB showed similarities lower than 90 % in all cases with respect to the closest relatives, confirming its phylogenetic affiliation. The strain showed a polar flagellum. The respiratory quinone was Q9. The major fatty acids were 16 : 1ω7c/16 : 1ω6c (summed feature 3), 18 : 1ω7c and 16 : 0. The strain was oxidase- and catalase-positive, but the arginine dihydrolase system was not present. Nitrate reduction, urease and β-galactosidase production, and aesculin hydrolysis were negative. The temperature range for growth was 4-34 °C, and the strain could grow at pH 11. The DNA G+C content was 58.5 mol%. DNA-DNA hybridization results showed values of less than 30 % relatedness with respect to the type strains of the eight most closely related species. Therefore, the dataset of genotypic, phenotypic and chemotaxonomic data support the classification of strain IB1.1T into a novel species of the genus Pseudomonas, for which the name Pseudomonasturukhanskensis sp. nov. is proposed. The type strain is IB1.1T (=VKM B-2935T=CECT 9091T).

  19. Oxytocin stimulates cell proliferation in vaginal cell line Vk2E6E7.

    Science.gov (United States)

    Kallak, Theodora K; Uvnäs-Moberg, Kerstin

    2017-03-01

    Objective During and after menopause, the symptoms of vaginal atrophy cause great discomfort and necessitate effective treatment options. Currently, vaginally applied oxytocin is being investigated as a treatment for the symptoms of vaginal atrophy in postmenopausal women. To clarify the mechanisms behind oxytocins effects on vaginal atrophy, the present study investigated the effects of oxytocin on cell proliferation in the cells of the Vk2E6E7 line, a non-tumour vaginal cell line. The study also compared the effects of oxytocin with those of estradiol (E2). Study design The effects of both oxytocin and E2 on the proliferation of Vk2E6E7 cells were investigated using Cell Proliferation ELISA BrdU Colorimetric Assay. The expression of both oxytocin and oxytocin receptor was studied in Vk2E6E7 cells using quantitative real-time polymerase chain reaction and immunofluorescent staining. Main outcome measures Cell proliferation and gene expression. Results Oxytocin increased cell proliferation both time dependently and dose dependently. This differed from the effect pattern observed in cells treated with E2. In addition, in oxytocin-treated cells, the oxytocin receptor was found to be co-localized with caveolin-1, indicating pro-proliferative signalling within the cell. Conclusions Oxytocin stimulates cell proliferation and the co-localization of oxytocin receptor with caveolin-1 in oxytocin-treated cells, supporting the role of oxytocin signalling in cell proliferation. In addition, these findings suggest that increased cell proliferation is one mechanism by which local vaginal oxytocin treatment increases vaginal thickness and relieves vaginal symptoms in postmenopausal women with vaginal atrophy.

  20. Clinical and genetic spectrum in limb-girdle muscular dystrophy type 2E

    Science.gov (United States)

    Semplicini, Claudio; Vissing, John; Dahlqvist, Julia R.; Stojkovic, Tanya; Bello, Luca; Witting, Nanna; Duno, Morten; Leturcq, France; Bertolin, Cinzia; D'Ambrosio, Paola; Eymard, Bruno; Angelini, Corrado; Politano, Luisa

    2015-01-01

    Objective: To determine the clinical spectrum of limb-girdle muscular dystrophy 2E (LGMD2E) and to investigate whether genetic or biochemical features can predict the phenotype of the disease. Methods: All LGMD2E patients followed in participating centers were included. A specific clinical protocol was created, including quantitative evaluation of motor, respiratory, and cardiac function. Phenotype was defined as severe or mild if the age at loss of ambulation occurred before or after 18 years. Molecular analysis of SGCB gene and biochemical features of muscle biopsies were reviewed. Results: Thirty-two patients were included (16 male, 16 female; age 7–67 years; 15 severe, 12 mild, and 5 unknown). Neurologic examination showed proximal muscle weakness in all patients, but distal involvement was also observed in patients with severe disease early in the disease course. Cardiac involvement was observed in 20 patients (63%) even before overt muscle involvement. Six patients had restrictive respiratory insufficiency requiring assisted ventilation (19%). Seventeen different mutations were identified, and 3 were recurrent. The c.377_384dup (13 alleles) was associated with the severe form, the c.-22_10dup (10) with the milder form, and the c.341C>T (9) with both. The entire sarcoglycan complex was undetectable by muscle immunohistochemistry or Western blot in 9/10 severe cases and reduced in 7/7 mild cases. The residual amount of sarcoglycan in muscle resulted a predictor of age at loss of ambulation. Conclusions: This study expands the spectrum of phenotype in β-sarcoglycanopathy and provides strong evidence that severity of clinical involvement may be predicted by SGCB gene mutation and sarcoglycan protein expression. PMID:25862795

  1. Plasmid profile as fingerprinting of typing Pseudomonas aeruginosa

    OpenAIRE

    El-Naggar, Wael; El-Emam, M; Hassan, R; George, S

    2014-01-01

    Pyocine production typing and restriction fragment length polymorphism (RFLP) of plasmid DNA with BamH1 (BamH1 RFLP) were compared for intraspecies discrimination of 100 Pseudomonas aeruginosa isolates. Typeability of pyocine production method was 76% while that of BamH1 RFLP was 100%. BamHl RFLP was highly discriminative so as to distinguish unrelated isolates of close lineage. However, it was not a good method to identify isolates of unrelated lineage because BamH1 RFLP appeared to be a sub...

  2. Electrical enhancement of biocide efficacy against Pseudomonas aeruginosa biofilms.

    Science.gov (United States)

    Blenkinsopp, S A; Khoury, A E; Costerton, J W

    1992-01-01

    When applied within a low-strength electric field (+/- 12 V/cm) with a low current density (+/- 2.1 mA/cm2), several industrial biocides exhibited enhanced killing action against Pseudomonas aeruginosa biofilms grown on stainless steel studs. Biocide concentrations lower than those necessary to kill planktonic cells of P. aeruginosa (1, 5, and 10 ppm of the active ingredients of kathon, glutaraldehyde, and quaternary ammonium compound, respectively) were bactericidal within 24 h when applied within our electrified device. PMID:1482196

  3. Regulation of phytotoxin production in Pseudomonas syringae pv. tabaci

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, L.M.; Ghosh, S.; Knight, T.J.; Unkefer, P.J. (Los Alamos National Lab., NM (United States))

    1991-05-01

    Pseudomonas syringae pv. tabaci, a pathogen of tobacco, is capable of colonizing the rhizosphere of many plants. This pathogen excretes tabtoxinine-{beta}-lactam (T{beta}L), an active site directed, irreversible inhibitor of glutamine synthetase. T{beta}L is produced in planta, in the rhizosphere, and under certain culture conditions. However, the factors which regulated T{beta}L production in these environments are unknown. As a first step in characterizing T{beta}L synthesis by P. syringae pv. tabaci, the authors have determined the effects of root exudates and various nutrients on production of T{beta}L by P. syringae pv. tabaci PT113.

  4. HOPM1 mediated disease resistance to Pseudomonas syringae in Arabidopsis

    Science.gov (United States)

    He, Sheng Yang [Okemos, MI; Nomura, Kinya [East Lansing, MI

    2011-11-15

    The present invention relates to compositions and methods for enhancing plant defenses against pathogens. More particularly, the invention relates to enhancing plant immunity against bacterial pathogens, wherein HopM1.sub.1-300 mediated protection is enhanced, such as increased protection to Pseudomonas syringae pv. tomato DC3000 HopM1 and/or there is an increase in activity of an ATMIN associated plant protection protein, such as ATMIN7. Reagents of the present invention further provide a means of studying cellular trafficking while formulations of the present inventions provide increased pathogen resistance in plants.

  5. Vaccines for Pseudomonas aeruginosa: A long and winding road

    Science.gov (United States)

    Priebe, Gregory P.; Goldberg, Joanna B.

    2015-01-01

    Summary Despite the recognition of Pseudomonas aeruginosa is an opportunistic pathogen, no vaccine against this bacteria have come to market. This review describes the current state-of-the-art in vaccinology for this bacterium. This includes a discussion of those at risk for infection, the types of vaccines and the approaches for empirical and targeted antigen selection under development, as well as a perspective on where the field should go. In addition, the challenges in developing a vaccine for those individuals at risk are discussed. PMID:24575895

  6. Ciprofloxacin susceptibility of Pseudomonas aeruginosa isolates from keratitis

    DEFF Research Database (Denmark)

    Lomholt, JA; Kilian, Mogens

    2003-01-01

    AIM: To examine the ciprofloxacin susceptibility of 106 Pseudomonas aeruginosa eye isolates from the United Kingdom, Denmark, India, the United States, and Australia, and to determine the molecular mechanisms of resistance. METHODS: Ciprofloxacin susceptibility was tested by an agar dilution method...... isolates of P aeruginosa from European countries are fully susceptible to ciprofloxacin and the concentration of ciprofloxacin eye drops used for local treatment (3000 mg/l) exceeds MIC values for strains recorded as resistant. Mutations in more than one target gene were associated with higher MIC values....

  7. Methods of detecting and controlling mucoid Pseudomonas biofilm production

    Science.gov (United States)

    Yu, Hongwei D. (Inventor); Qiu, Dongru (Inventor)

    2013-01-01

    Compositions and methods for detecting and controlling the conversion to mucoidy in Pseudomonas aeruginosa are disclosed. The present invention provides for detecting the switch from nonmucoid to mucoid state of P. aeruginosa by measuring mucE expression or MucE protein levels. The interaction between MucE and AlgW controls the switch to mucoidy in wild type P. aeruginosa. Also disclosed is an alginate biosynthesis heterologous expression system for use in screening candidate substances that inhibit conversion to mucoidy.

  8. Alkaline cyanide biodegradation by Pseudomonas pseudoalcaligenes CECT5344.

    Science.gov (United States)

    Luque-Almagro, V M; Blasco, R; Huertas, M J; Martínez-Luque, M; Moreno-Vivián, C; Castillo, F; Roldán, M D

    2005-02-01

    Pseudomonas pseudoalcaligenes CECT5344 uses cyanide, cyanate, beta-cyanoalanine, and other cyanoderivatives as nitrogen sources under alkaline conditions, which prevents volatile HCN (pK(a) 9.2) formation. The cyanide consumed by this strain is stoichiometrically converted into ammonium. In addition, this bacterium grows with the heavy metal, cyanide-containing waste water generated by the jewellery industry, and is also a cyanide-resistant strain which induces an alternative oxidase and a siderophore-based mechanism for iron acquisition in the presence of cyanide. The detection of cyanase and beta-cyanoalanine nitrilase activities in cyanide-induced cells suggests their implication in the cyanide degradation pathway.

  9. The sigma(54) regulon (sigmulon) of Pseudomonas putida

    DEFF Research Database (Denmark)

    Cases, I.; Ussery, David; de Lorenzo, V.

    2003-01-01

    , the sigma(54) regulon has been studied both in Escherichia coli, Salmonella typhimurium and several species of the Rhizobiaceae. Here we present the analysis of the sigma(54) regulon (sigmulon) in the complete genome of Pseudomonas putida KT2440. We have developed an improved method for the prediction......% of the sigma(54)-dependent promoters of P. putida with high confidence. Our analysis has revealed new functions for sigma(54) and, by means of comparative analysis with the previous studies, we have drawn a potential mechanism for the evolution of this regulatory system....

  10. Community-Acquired urinary tract infection by pseudomonas oryzihabitans

    Directory of Open Access Journals (Sweden)

    Sunita M Bhatawadekar

    2013-01-01

    Full Text Available Pseudomonas oryzihabitans and Chrysomonas luteola has been placed in CDC group Ve2 and Ve1 respectively. These bacteria appear to be emerging pathogens. P. oryzihabitans was isolated from cases of bacteremia, CNS infections, wound infections, peritonitis, sinusitis, catheter associated infections in AIDS patient, and pneumonia. Most of the reports of P. oryzihabitans infection were of nosocomial origin in individuals with some predisposing factors. We report here a case of community acquired UTI by P. oryzihabitans in an immune-competent patient with stricture of urethra.

  11. An unusual presentation of Pseudomonas aeruginosa blebitis following combined surgery

    Directory of Open Access Journals (Sweden)

    Shabana Bharathi

    2014-01-01

    Full Text Available We report a case of blebitis that occurred 3 years later following a combined glaucoma and cataract surgery. It was an atypical presentation, as patient had no classical fiery looking signs of blebitis despite the isolated organism being Pseudomonas aeruginosa. Improvized surgical techniques like use of Mitomycin C, releasable flap sutures though considered as part of the recommended procedure for better surgical outcomes, their role as potential risk factors for visually blinding complications like endophthalmitis are often overlooked. This case report throws light on such risk factors for bleb associated infections and recommends removal or trimming of all releasable sutures and the need for a regular postoperative follow-up.

  12. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  13. Adaptive synonymous mutations in an experimentally evolved Pseudomonas fluorescens population

    DEFF Research Database (Denmark)

    Bailey, Susan; Hinz, Aaron; Kassen, Rees

    2014-01-01

    Conventional wisdom holds that synonymous mutations, nucleotide changes that do not alter the encoded amino acid, have no detectable effect on phenotype or fitness. However, a growing body of evidence from both comparative and experimental studies suggests otherwise. Synonymous mutations have been...... in an experimentally evolved population of Pseudomonas fluorescens. We show experimentally that these mutations increase fitness by an amount comparable to non-synonymous mutations and that the fitness increases stem from increased gene expression. These results provide unequivocal evidence that synonymous mutations...... can drive adaptive evolution and suggest that this class of mutation may be underappreciated as a cause of adaptation and evolutionary dynamics....

  14. Development of potent inhibitors of pyocyanin production in Pseudomonas aeruginosa.

    Science.gov (United States)

    Miller, Laura C; O'Loughlin, Colleen T; Zhang, Zinan; Siryaporn, Albert; Silpe, Justin E; Bassler, Bonnie L; Semmelhack, Martin F

    2015-02-12

    The development of new approaches for the treatment of antimicrobial-resistant infections is an urgent public health priority. The Pseudomonas aeruginosa pathogen, in particular, is a leading source of infection in hospital settings, with few available treatment options. In the context of an effort to develop antivirulence strategies to combat bacterial infection, we identified a series of highly effective small molecules that inhibit the production of pyocyanin, a redox-active virulence factor produced by P. aeruginosa. Interestingly, these new antagonists appear to suppress P. aeruginosa virulence factor production through a pathway that is independent of LasR and RhlR.

  15. Occupational Survey Report. Ground Radio Communications, AFSC 2E1X3

    Science.gov (United States)

    2003-10-01

    analyzed the data, and wrote the final report. Mr. Tyrone Hill provided computer-programming support, and Ms. Dolores Navarro and Ms. Sherry Evans...AFSC 2E1X3 members selected military-related education and training opportunities and medical/ dental care for AD members as their second and third...TRAINING OPPORTUNITIES 52 2.52 55 2.49 50 2.34 MEDICAL/ DENTAL CARE FOR AD MEMBER 60 2.57 55 2.56 53 2.48 MEDICAL/ DENTAL CARE FOR FAMILY MEMBERS 48

  16. Effect of piperine on CYP2E1 enzyme activity of chlorzoxazone in healthy volunteers.

    Science.gov (United States)

    Bedada, Satish Kumar; Boga, Praveen Kumar

    2017-12-01

    1. The purpose of the present study was to investigate the effect of piperine (PIP) on CYP2E1 enzyme activity and pharmacokinetics of chlorzoxazone (CHZ) in healthy volunteers. 2. An open-label, two period, sequential study was conducted in 12 healthy volunteers. A single dose of PIP 20 mg was administered daily for 10 days during treatment phase. A single dose of CHZ 250 mg was administered during control and after treatment phases under fasting conditions. The blood samples were collected at predetermined time intervals after CHZ dosing and analyzed by HPLC. 3. Treatment with PIP significantly enhanced maximum plasma concentration (Cmax) (3.14-4.96 μg/mL), area under the curve (AUC) (10.46-17.78 μg h/mL), half life (T1/2) (1.26-1.82 h) and significantly decreased elimination rate constant (Kel) (0.57-0.41 h (-) (1)), apparent oral clearance (CL/F) (24.76-13.65 L/h) of CHZ when compared to control. In addition, treatment with PIP significantly decreased Cmax (0.22-0.15 μg/mL), AUC (0.94-0.68 μg h/mL), T1/2 (2.54-1.68 h) and significantly increased Kel (0.32-0.43 h (-) (1)) of 6-hydroxychlorzoxazone (6-OHCHZ) as compared to control. Furthermore, treatment with PIP significantly decreased metabolite to parent (6-OHCHZ/CHZ) ratios of Cmax, AUC, T1/2 and significantly increased Kel ratio of 6-OHCHZ/CHZ, which indicate the decreased formation of CHZ to 6-OHCHZ. 4. The results suggest that altered pharmacokinetics of CHZ might be attributed to PIP mediated inhibition of CYP2E1 enzyme, which indicate significant pharmacokinetic interaction present between PIP and CHZ. The inhibition of CYP2E1 by PIP may represent a novel therapeutic benefit for minimizing ethanol induced CYP2E1 enzyme activity and results in reduced hepatotoxicity of ethanol.

  17. A new look at an energetic (e,2e) reaction: Binary versus recoil

    Energy Technology Data Exchange (ETDEWEB)

    Kheifets, A S [Research School of Physics, Australian National University, Canberra ACT 0200 (Australia); Naja, A; Casagrande, E M Staicu; Lahmam-Bennani, A, E-mail: A.Kheifets@anu.edu.a [Universite Paris-Sud 11, Laboratoire des Collisions Atomiques et Moleculaires, 91405 Orsay Cedex (France)

    2009-11-01

    We analyze the recoil-to-binary peak ratio in an energetic (e,2e) reaction on the valence ns sub-shell of noble gas atoms. Dramatic qualitative change in this ratio dependence on the ejected electron energy can be explained by variation of reflectivity of the short-range Hartree-Fock potential. The reflectivity increases profoundly from lighter (He) to heavier (Ne and Ar) noble gas atoms because of modification of the scattering phases due to occupation of the target p orbitals (Levinson theorem). This effect is further modified due to strong inter-shell correlations in Ar. These theoretical predictions are confirmed experimentally.

  18. An X-ray mapper for the Mu2e experiment

    Energy Technology Data Exchange (ETDEWEB)

    Oh, S. H. [Duke U.; Wang, C. [Duke U.

    2015-10-17

    We report on the construction and performance of a scanner using a collimated x-ray beam to find the positions of wires, straws, slots and spheres. The technique is based on measuring the transmission rate of the beam, and their positions can be determined ~25 μm accuracy. The spheres or slots attached to the detector can also be optically surveyed externally to transfer the coordinates of wires and straws to other detector systems. The scanner was developed for the Mu2e straw tracker but may have a wide range of applications.

  19. Event display of a H -> 2e2mu candidate event

    CERN Multimedia

    ATLAS, Collaboration

    2012-01-01

    Event display of a H -> 2e2mu candidate event with m(4l) = 122.6 (123.9) GeV without (with) Z mass constraint. The masses of the lepton pairs are 87.9 GeV and 19.6 GeV. The event was recorded by ATLAS on 18-Jun-2012, 11:07:47 CEST in run number 205113 as event number 12611816. Zoom into the tracking detector. Muon tracks are colored red, electron tracks and clusters in the LAr calorimeter are colored green.

  20. Pseudomonas sax genes overcome aliphatic isothiocyanate-mediated non-host resistance in Arabidopsis

    Science.gov (United States)

    Jun Fan; Casey Crooks; Gary Creissen; Lionel Hill; Shirley Fairhurst; Peter Doerner; Chris Lamb

    2011-01-01

    Most plant-microbe interactions do not result in disease; natural products restrict non-host pathogens. We found that sulforaphane (4-methylsulfinylbutyl isothiocyanate), a natural product derived from aliphatic glucosinolates, inhibits growth in Arabidopsis of non-host Pseudomonas bacteria in planta. Multiple sax genes (saxCAB/F/D/G) were identified in Pseudomonas...

  1. Erythromycin inhibits Pseudomonas aeruginosa-induced tumour necrosis factor-alpha production in human whole blood

    NARCIS (Netherlands)

    Schultz, M. J.; Speelman, P.; van der Poll, T.

    2001-01-01

    Erythromycin has been shown to be beneficial for panbronchiolitis, a disorder linked to infection with Pseudomonas aeruginosa. Erythromycin, but not the anti-Pseudomonas antibiotics imipenem, ceftazidime, gentamicin and ciprofloxacin, caused a dose-dependent decrease in the production of tumour

  2. De novo production of the monoterpenoid geranic acid by metabolically engineered Pseudomonas putida

    OpenAIRE

    Mi, Jia; Becher, Daniela; Lubuta, Patrice; Dany, Sarah; Tusch, Kerstin; Schewe, Hendrik; Buchhaupt, Markus; Schrader, Jens

    2014-01-01

    Background Production of monoterpenoids as valuable chemicals using recombinant microbes is a growing field of interest. Unfortunately, antimicrobial activity of most monoterpenoids hampers a wide application of microorganisms for their production. Strains of Pseudomonas putida, a fast growing and metabolically versatile bacterium, often show an outstanding high tolerance towards organic solvents and other toxic compounds. Therefore, Pseudomonas putida constitutes an attractive alternative ho...

  3. Genome sequence of Pseudomonas sp. strain PAMC 25886, isolated from alpine glacial cryoconite.

    Science.gov (United States)

    Shin, Seung Chul; Kim, Su Jin; Hong, Soon Gyu; Ahn, Do Hwan; Lee, Yung Mi; Lee, Hyoungseok; Lee, Jungeun; Park, Hyun

    2012-04-01

    Pseudomonas spp. have shown characteristics of efficiently metabolizing environmental pollutants and also producing exopolysaccharides known as biofilms. Here we present the draft genome sequence of Pseudomonas sp. strain PAMC 25886, which was isolated from glacier cryoconite in the Alps mountain permafrost region and which may provide further insight into biodegradative and/or biofilm-producing mechanisms in a cold environment.

  4. 40 CFR 180.1261 - Xanthomonas campestris pv. vesicatoria and Pseudomonas syringae pv. tomato specific Bacteriophages.

    Science.gov (United States)

    2010-07-01

    ... and Pseudomonas syringae pv. tomato specific Bacteriophages. 180.1261 Section 180.1261 Protection of.... vesicatoria and Pseudomonas syringae pv. tomato specific Bacteriophages. An exemption from the requirement of... syringae pv. tomato specific bacteriophages in or on pepper and tomato. ...

  5. Regulation of the biosynthesis of cyclic lipopeptides from Pseudomonas putida PCL1445

    NARCIS (Netherlands)

    Dubern, Jean-Frédéric

    2006-01-01

    Pseudomonas putida strain PCL1445 produces two cyclic lipopeptides, named putisolvins I and II, which represent a Novel class of biosurfactants. Putisolvins reduce the surface tension between liquid and air, and disrupt already existing biofilms of several Pseudomonas sp., including those of the

  6. Regulation of pqs quorum sensing via catabolite repression control in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Zhang, Lianbo; Gao, Qingguo; Chen, Wanying

    2013-01-01

    that the Pseudomonas aeruginosa catabolite repression control protein regulates the Pseudomonas quinolone signal quorum sensing, which further controls synthesis of virulence factor pyocyanin, biofilm formation and survival during infection models. Our study suggests that deregulation of the catabolite repression by P...

  7. Dual Infection by Burkholderia Cepaciaand Pseudomonas Putida in an Infective Endocarditis Case.

    Science.gov (United States)

    Khan, Maria; Lalani, Farida Khurram; Ikram, Aamer; Zaman, Gohar; Ahmed, Parvez

    2017-06-01

    Infective endocarditis is rarely caused by Burkholderia cepacia. Pseudomonas putidahas not been reported to cause infective endocarditis so far. This is the first case of infective endocarditis being reported, that is caused by Pseudomonas putidaand Burkholderia cepaciain an immunocompetent host with no predisposing factors. Aortic valve replacement surgery was carried out and antibiotics were given, to which the patient responded well and recovered.

  8. A Mathematical model to investigate quorum sensing regulation and its heterogenecity in pseudomonas syringae on leaves

    Science.gov (United States)

    The bacterium Pseudomonas syringae is a plant-pathogen, which through quorum sensing (QS), controls virulence. In this paper, by means of mathematical modeling, we investigate QS of this bacterium when living on leaf surfaces. We extend an existing stochastic model for the formation of Pseudomonas s...

  9. Bloodstream infections caused by Pseudomonas spp.; how to detect carbapenemase producers directly from positive blood cultures ?

    OpenAIRE

    Dortet, Laurent; Boulanger, Anne; Poirel, Laurent; Nordmann, Patrice

    2014-01-01

    The Carba NP test has been evaluated to detect carbapenemase-producing Pseudomonas spp. directly from blood cultures. This rapid and cost-effective test permits an early identification of carbapenemase-producing Pseudomonas spp. directly from blood cultures with excellent sensitivity and specificity. Results may be useful in particular for guiding the first-line therapy and epidemiological purposes.

  10. The nitrogen-fixation island insertion site is conserved in diazotrophic Pseudomonas stutzeri and Pseudomonas sp. isolated from distal and close geographical regions.

    Directory of Open Access Journals (Sweden)

    Anastasia Venieraki

    Full Text Available The presence of nitrogen fixers within the genus Pseudomonas has been established and so far most isolated strains are phylogenetically affiliated to Pseudomonas stutzeri. A gene ortholog neighborhood analysis of the nitrogen fixation island (NFI in four diazotrophic P. stutzeri strains and Pseudomonas azotifigens revealed that all are flanked by genes coding for cobalamin synthase (cobS and glutathione peroxidise (gshP. The putative NFIs lack all the features characterizing a mobilizable genomic island. Nevertheless, bioinformatic analysis P. stutzeri DSM 4166 NFI demonstrated the presence of short inverted and/or direct repeats within both flanking regions. The other P. stutzeri strains carry only one set of repeats. The genetic diversity of eleven diazotrophic Pseudomonas isolates was also investigated. Multilocus sequence typing grouped nine isolates along with P. stutzeri and two isolates are grouped in a separate clade. A Rep-PCR fingerprinting analysis grouped the eleven isolates into four distinct genotypes. We also provided evidence that the putative NFI in our diazotrophic Pseudomonas isolates is flanked by cobS and gshP genes. Furthermore, we demonstrated that the putative NFI of Pseudomonas sp. Gr65 is flanked by inverted repeats identical to those found in P. stutzeri DSM 4166 and while the other P. stutzeri isolates harbor the repeats located in the intergenic region between cobS and glutaredoxin genes as in the case of P. stutzeri A1501. Taken together these data suggest that all putative NFIs of diazotrophic Pseudomonas isolates are anchored in an intergenic region between cobS and gshP genes and their flanking regions are designated by distinct repeats patterns. Moreover, the presence of almost identical NFIs in diazotrophic Pseudomonas strains isolated from distal geographical locations around the world suggested that this horizontal gene transfer event may have taken place early in the evolution.

  11. Systematic investigations on the biodegradation and viscosity reduction of long chain hydrocarbons using Pseudomonas aeruginosa and Pseudomonas fluorescens.

    Science.gov (United States)

    Sakthipriya, N; Doble, Mukesh; Sangwai, Jitendra S

    2016-03-01

    The use of microorganisms has been researched extensively for possible applications related to hydrocarbon degradation in the petroleum industry. However, attempts to improve the effect of microorganisms on the viscosity of hydrocarbons, which find potential use in the development of robust models for biodegradation, have been rarely documented. This study investigates the degradation of long chain hydrocarbons, such as hexadecane and eicosane using Pseudomonas fluorescens PMMD3 (P. fluorescens) and Pseudomonas aeruginosa CPCL (P. aeruginosa). P. aeruginosa used here is isolated from petroleum contaminated sediments and the P. fluorescens is from the coastal area, and both have hydrocarbon degrading genes. The degradation of hydrocarbons is studied using carbon profiling and reduction in viscosity pre- and post-degradation of hydrocarbons. The carbon profiling has been obtained using gas chromatography-mass spectroscopy (GC-MS), and Fourier transform infrared spectrometer (FTIR) results. GC-MS results have indicated an improved biodegradation of hydrocarbons by 77-93% in one day. The yield coefficients of biomass (YX/S) for P. aeruginosa and P. fluorescens using hexadecane as a carbon source are 1.35 and 0.81 g g(-1), and the corresponding values with eicosane are 0.84 and 0.88 g g(-1). The viscosity of hexadecane is reduced by the order of 53 and 47%, while that of eicosane was reduced by 53 and 65%, using P. aeruginosa and P. fluorescens, respectively. This study also presents information on the activity of enzymes responsible for the hydrocarbon degradation. Pseudomonas species have shown their use in potential applications for bioremediation, oil-spill treatment, and flow assurance. We believe that this study will also provide stringent tests for possible model development for the bioremediation of long chain paraffins suitable for oilfield applications.

  12. Free radical scavenging potency of quercetin catecholic colonic metabolites: Thermodynamics of 2H(+)/2e(-) processes.

    Science.gov (United States)

    Amić, Ana; Lučić, Bono; Stepanić, Višnja; Marković, Zoran; Marković, Svetlana; Dimitrić Marković, Jasmina M; Amić, Dragan

    2017-03-01

    Reaction energetics of the double (2H(+)/2e(-)), i.e., the first 1H(+)/1e(-) (catechol→ phenoxyl radical) and the second 1H(+)/1e(-) (phenoxyl radical→ quinone) free radical scavenging mechanisms of quercetin and its six colonic catecholic metabolites (caffeic acid, hydrocaffeic acid, homoprotocatechuic acid, protocatechuic acid, 4-methylcatechol, and catechol) were computationally studied using density functional theory, with the aim to estimate the antiradical potency of these molecules. We found that second hydrogen atom transfer (HAT) and second sequential proton loss electron transfer (SPLET) mechanisms are less energy demanding than the first ones indicating 2H(+)/2e(-) processes as inherent to catechol moiety. The Gibbs free energy change for reactions of inactivation of selected free radicals indicate that catecholic colonic metabolites constitute an efficient group of more potent scavengers than quercetin itself, able to deactivate various free radicals, under different biological conditions. They could be responsible for the health benefits associated with regular intake of flavonoid-rich diet. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. [Genetic polymorphism of cytochrome P450 2E1 and the risk of nasopharyngeal carcinoma].

    Science.gov (United States)

    Ben Chaaben, Arij; Abaza, Hajer; Douik, Hayet; Chaouch, Leila; Ayari, Fayza; Ouni, Nesrine; Mamoghli, Tasnim; Ben Guezella, Dorra; Mejri, Rachida; Harzallah, Latifa; Guemira, Fethi

    2015-12-01

    Cytochrome P450 2E1 (CYP2E1) is a detoxifying enzyme that belongs to the phase I metabolism of xenobiotics. This enzyme is encoded by a highly polymorphic gene whose common polymorphism corresponds to the substitution of cytosine (C) and thymine (T) at position -1019 (rs2031920). This polymorphism has been identified in several cancers including nasopharyngeal cancer (NPC). The study involved 124 patients with nasopharyngeal carcinoma, compared with 166 healthy controls. The presence or absence of the polymorphism is determined by PCR-RFLP. The frequency comparison between the two groups is determined by the χ(2) test. The analysis of our results showed a significant difference between the two groups regarding the mutant genotype (C2/C2) (5% vs. 0.5%, P=0.04) and has a risk factor for NPC in Tunisia (OR=8.39; CI 95% [0.99-388.1]). Also, the C2 allele was significantly associated with the group of patients than the control group (6% vs. 2%, P=0.016) and increased three times the risk of NPC in Tunisia (OR=2.99, CI 95% [1.12-8.79]). Our results confirm the results reported in other populations and emphasize the importance of the involvement of this gene in the development of detoxification of the NPC, which seems more and more strongly associated with environmental factors. Copyright © 2015 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

  14. Impact of Silver Nanoparticle Transformation on Pseudomonas aeruginosa GFP Biofilm

    Science.gov (United States)

    Adegboye, Temitope Azeezat

    Silver nanoparticles (Ag NP) undergo transformations when released into the environment and often the transformed nanoparticles exhibit different behavior from the pristine analog. It is important to understand the influence of Ag NP transformation (particularly sulfidation) on its potential impacts in order to determine the effects of environmental transformation on biofilms. The goal of our study was to investigate interactions of polyvinylpyrrolidone-capped (PVP) pristine and transformed Ag NP (30 - 50 nm particle size) with bacterial biofilm to assess their impacts on biofilm communities. In this study, Pseudomonas aeruginosa GFP (ATCCRTM 10145GFP(TM)) biofilms were subjected to similar concentrations of pristine- Ag NP and transformed- Ag2S NP under environmentally relevant conditions. Residual concentrations of dissolved silver and NP after exposure to biofilms were evaluated by ICP-AES (Inductively Coupled Plasma Atomic Emission Spectroscopy) analysis. The morphological properties of Pseudomonas aeruginosa GFP (P. aeruginosa) biofilms after exposure to both forms of silver nanoparticles were characterized by cell viability studies (using microplate reader and live/dead assay) and scanning electron microscopy (SEM). We also analyzed the distribution and size of investigated silver nanoparticles within P.aeruginosa biofilms using SEM coupled with EDS. Here, we report that transformed silver nanoparticle (Ag2S NP) exhibit reduced biofilm inactivation effects against P. aeruginosa biofilms compared to its pristine form (Ag NP). This result could be explained by a lower uptake of Ag2S nanoparticle by P. aeruginosa biofilms demonstrated by ICP-AES and SEM/EDS analysis.

  15. Copper uptake by Pseudomonas aeruginosa isolated from infected burn patients.

    Science.gov (United States)

    Abboud, Muayad M; Saeed, Humodi A; Tarawneh, Khaled A; Khleifat, Khaled M; Al Tarawneh, Amjad

    2009-09-01

    Pseudomonas aeruginosa was isolated from infected burn patients and characterized by standard biochemical tests. The in vitro copper uptake was compared between this isolated pathogenic strain and two non-pathogenic control strains of gram positive bacteria Bacillus thuringiensis strain Israelis as well as gram negative bacteria Enterobacter aerogenes. Maximum copper uptake of 470 ppm/g biomass was obtained by P. aeruginosa strain, while the control strains B. thuringiensis and Enterobacter aerogenes had copper uptake of 350 and 383 ppm/g biomass, respectively. However, the lowest copper uptake (60 ppm/g biomass) was observed with another control the saprophytic strain Pseudomonas (Shewanella) putrefaciens. A further investigation regarding the effect of copper toxicity on bacterial growth, gave an MIC score of 600 ppm for P. aeruginosa strain compared to 460 and 300 ppm for the two gram positive and gram negative control strains, respectively. In tandem with these in vitro findings, blood analysis on burn patients infected with P. aeruginosa has indicated a selective decrease of copper (hypocupremia) and ceruloplasmin plasma levels. The iron metabolism was also affected by this copper deprivation leading to a similar decrease in plasma levels of PCV, iron, total iron binding capacity, and transferrin. All these hematological changes were significantly different (P < 0.05) from the matched group of non-infected burn patients. The observed hypocupremia in infected burn patients was attributed to demanding scavenger ability by P. aeruginosa strain for the copper of plasma.

  16. Biodegradasi Petroleum dan Hidrokarbon Eikosana oleh Isolat Bakteri Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Faiqah Umar

    2015-01-01

    Full Text Available Biodegradation of petroleum and hydrocarbon eicosane by Pseudomonas aeruginosa isolate. Hydrocarbon are important environmental contaminants in soil and water. These compounds have a potential risk to human health, as many of them are carsinogenic and toxic to marine organisms such as diatome, gasthrophode, mussel, and fish. The purpose of this research was to know the ability of Pseudomonas aeruginosa to degradate the hydrocarbon (petroleum Hundill and eicosane substrate. Growing test used in two steps, the preculture and culture step. The biodegradation capacity was measured by quantitative and qualitative tests. The essay showed an increasing biodegradation capacitypercentage of bacteria cell mass on hydrocarbon substrate. The percentage on petroleum Hundill substrat as follows; log phase was 51,6%, descelerate phase was 73%, and linear phase was 81,4%. On eicosane substrate as follows; log phase was 62,7%, descelerate phase was 85,2%, and linear phase was 85,2%. The qualitative biodegradation capacity by chromatography result showed separate enchained of carbon n-alkana in each growth phase on petroleum Hundill substrate. Carbon chain termination as follows; C11, C12, C14, C15, C16, C18, C22 on log phase, C12, C17, C19, C20, C24 on descelerate phase, and C12 until C25 even better on linear phase.

  17. PARTIAL PURIFICATION AND CHARACTERIZATION OF ALKALOPHILIC PROTEASE FROM PSEUDOMONAS AERUGINOSA

    Directory of Open Access Journals (Sweden)

    R. Satheeskumar

    2013-10-01

    Full Text Available Partial purification and characterization of alkalophilic protease production from Pseudomonas aeruginosa was isolated from the gut of marine and coastal waters shrimp Penaeus monodon. The protease production was assayed in submerged fermentation to produce maximum protease activity (423 ± 0.09 U/ml. The enzyme was precipitated with ammonium sulphate and partially purified by ion exchange chromatography through DEAE Sephadex A-50 column. In 10th fraction showed maximum protease activity (734 ± 0.18 U/ml with increase in purification fold. The molecular weight of protease from Pseudomonas aeruginosa was recorded as 60 kDa. The stability of protease was tested at various pH and temperature; it showed maximum protease activity at pH-9 and temperature 50ºC. Among the various surfactants tested for enzyme stability, maximum activity was retained in poly ethylene glycol. The compatibility of protease enzyme with various commercial detergents; the enzyme retained maximum protease activity in tide. The results are indicated that all these properties make the bacterial proteases are most suitable for wide industrial applications.

  18. Pseudomonas aeruginosa: an uncommon cause of diabetic foot infection.

    Science.gov (United States)

    Young, Heather; Knepper, Bryan; Hernandez, Whitney; Shor, Asaf; Bruntz, Merribeth; Berg, Chrystal; Price, Connie S

    2015-03-01

    Pseudomonas aeruginosa has traditionally been considered a common pathogen in diabetic foot infection (DFI), yet the 2012 Infectious Diseases Society of America guideline for DFI states that "empiric therapy directed at P aeruginosa is usually unnecessary." The objective of this study was to evaluate the frequency of P aeruginosa isolated from bone or tissue cultures from patients with DFI. This study is a cross-sectional survey of diabetic patients presenting with a foot infection to an urban county hospital between July 1, 2012, and December 31, 2013. All of the patients had at least one debridement procedure during which tissue or bone cultures from operative or bedside debridements were obtained. The χ(2) test and the t test of means were used to determine relationships between variables and the frequency of P aeruginosa in culture. The median number of bacteria isolated from DFI was two. Streptococcus spp and Staphylococcus aureus were the most commonly isolated organisms; P aeruginosa was isolated in only five of 112 patients (4.5%). The presence of P aeruginosa was not associated with the patient's age, glycosylated hemoglobin level, tobacco abuse, the presence of osteomyelitis, a prescription for antibiotic drugs in the preceding 3 months, or the type of operative procedure. Pseudomonas aeruginosa was an infrequent isolate from DFI in this urban, underserved diabetic population. The presence of P aeruginosa was not associated with any measured risk factors. By introducing a clinical practice guideline, we hope to discourage frontline providers from using routine antipseudomonal antibiotic drugs for DFI.

  19. Isolation of Pseudomonas cepacia in cystic fibrosis patient

    Directory of Open Access Journals (Sweden)

    Elizabeth de Andrade Marques

    1993-03-01

    Full Text Available Pulmonary infection on cystic fibrosis (CF patients are associated with a limited qualitative number of microorganisms. During the colonization process, Staphylococcus aureus usually preceedes Pseudomonas aeruginosa. This latter is at first non-mucoid, being replaced or associated to a mucoid morphotype which is rare in other diseases. In 1980, Pseudomonas cepacia appeared as an important agent in CF pulmonary infections with a mean frequency of about 6.1% isolations in different parts of the world. The primus colonization mainly occurs in the presence of pre-existent tissue lesions and the clinical progress of the disease is variable. In some patients it can be fulminant; in others it can cause a gradual and slow decrease in their pulmonary functions. The concern with this germ isolation is justified by its antibiotic multiple resistence and the possibility of direct transmission from a colonized patient to a non-colonized one. We reported the first case of P. cepacia infection in a CF patient in our area. The microbiological attendance to this patient had been made from 1986 to 1991 and the first positive culture appeared in 1988. The sensitivity profile showed that the primus colonization strain was sensitive to 9 of 17 tested antibiotics, however in the last culture the strain was resistent to all antibiotics. These data corroborate the need for monitoring the bacterial flora on CF patients respiratory system.

  20. Expression, purification, and characterization of formaldehyde dehydrogenase from Pseudomonas aeruginosa.

    Science.gov (United States)

    Zhang, Wangluo; Chen, Shuai; Liao, Yuanping; Wang, Dingli; Ding, Jianfeng; Wang, Yingming; Ran, Xiaoyuan; Lu, Daru; Zhu, Huaxing

    2013-12-01

    As a member of zinc-containing medium-chain alcohol dehydrogenase family, formaldehyde dehydrogenase (FDH) can oxidize toxic formaldehyde to less active formate with NAD(+) as a cofactor and exists in both prokaryotes and eukaryotes. Most FDHs are well known to be glutathione-dependent in the catalysis of formaldehyde oxidation, but the enzyme from Pseudomonas putida is an exception, which is independent of glutathione. To identify novel glutathione-independent FDHs from other bacterial strains and facilitate the corresponding structural and enzymatic studies, high-level soluble expression and efficient purification of these enzymes need to be achieved. Here, we present molecular cloning, expression, and purification of the FDH from Pseudomonas aeruginosa, which is a Gram-negative pathogenic bacterium causing opportunistic human infection. The FDH of P. aeruginosa shows high sequence identity (87.97%) with that of P. putida. Our results indicated that coexpression with molecular chaperones GroES, GroEL, and Tig has significantly attenuated inclusion body formation and improved the solubility of the recombinant FDH in Escherichiacoli cells. A purification protocol including three chromatographic steps was also established to isolate the recombinant FDH to homogeneity with a yield of ∼3.2 mg from 1L of cell culture. The recombinant P. aeruginosa FDH was properly folded and biologically functional, as demonstrated by the mass spectrometric, crystallographic, and enzymatic characterizations of the purified proteins. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Functional study of elafin cleaved by Pseudomonas aeruginosa metalloproteinases

    Science.gov (United States)

    Guyot, Nicolas; Bergsson, Gudmundur; Butler, Marcus W.; Greene, Catherine M.; Weldon, Sinead; Kessler, Efrat; Levine, Rodney L.; O’Neill, Shane J.; Taggart, Clifford C.; McElvaney, Noel G.

    2012-01-01

    Elafin is a 6 kDa innate immune protein present at several epithelial surfaces including the pulmonary epithelium. It is a canonical protease inhibitor of two neutrophil serine proteases (neutrophil elastase (NE) and proteinase 3) with the capacity to covalently bind extracellular matrix proteins by transglutamination. In addition to these properties, elafin also possesses antimicrobial and immunomodulatory activities. The aim of the present study was to investigate the effect of Pseudomonas aeruginosa proteases on elafin function. We found that P. aeruginosa PAO1-conditioned medium and two purified Pseudomonas metalloproteases, pseudolysin (elastase) and aeruginolysin (alkaline protease), were able to cleave recombinant elafin. Pseudolysin was shown to inactivate the anti-NE activity of elafin by cleaving its protease-binding loop. Interestingly, antibacterial properties of elafin against PAO1 were found to be unaffected after pseudolysin treatment. In contrast to pseudolysin, aeruginolysin failed to inactivate the inhibitory properties of elafin against NE. Aeruginolysin cleaved elafin at the amino-terminal Lys6-Gly7 peptide bond resulting in a decreased ability to covalently bind purified fibronectin following transglutaminase activity. In conclusion, this study provides evidences that elafin is susceptible to proteolytic cleavage at alternative sites by P. aeruginosa metalloproteinases, which can affect different biological functions of elafin. PMID:20370321

  2. Interspecies Interaction between Pseudomonas aeruginosa and Other Microorganisms

    Science.gov (United States)

    Tashiro, Yosuke; Yawata, Yutaka; Toyofuku, Masanori; Uchiyama, Hiroo; Nomura, Nobuhiko

    2013-01-01

    Microbes interact with each other in multicellular communities and this interaction enables certain microorganisms to survive in various environments. Pseudomonas aeruginosa is a highly adaptable bacterium that ubiquitously inhabits diverse environments including soil, marine habitats, plants and animals. Behind this adaptivity, P. aeruginosa has abilities not only to outcompete others but also to communicate with each other to develop a multispecies community. In this review, we focus on how P. aeruginosa interacts with other microorganisms. P. aeruginosa secretes antimicrobial chemicals to compete and signal molecules to cooperate with other organisms. In other cases, it directly conveys antimicrobial enzymes to other bacteria using the Type VI secretion system (T6SS) or membrane vesicles (MVs). Quorum sensing is a central regulatory system used to exert their ability including antimicrobial effects and cooperation with other microbes. At least three quorum sensing systems are found in P. aeruginosa, Las, Rhl and Pseudomonas quinolone signal (PQS) systems. These quorum-sensing systems control the synthesis of extracellular antimicrobial chemicals as well as interaction with other organisms via T6SS or MVs. In addition, we explain the potential of microbial interaction analysis using several micro devices, which would bring fresh sensitivity to the study of interspecies interaction between P. aeruginosa and other organisms. PMID:23363620

  3. Biochemical and genetic studies on degradation of chlorobenzoates by Pseudomonas.

    Science.gov (United States)

    Singh, H; Kahlon, R S

    1989-01-01

    The chlorobenzoates constitute an important class of recalcitrant compounds polluting this biosphere. Two bacterial strains B16 (Pseudomonas aeruginosa) and DT4 (Pseudomonas sp.) isolated by enrichment technique were found to utilize 2-chlorobenzoic acid (2-Cba) and 4-chlorobenzoic acid (4-Cba) respectively as sole source of carbon and energy. 2-Cba and 4-Cba were supplemented in synthetic medium at 1500 micrograms/ml and 1000 micrograms/ml (w/v) respectively. Addition of 100 micrograms/ml (w/v) yeast extract stimulated growth of cultures. Degradation studies revealed that substrates were degraded without release of chloride ion with possible accumulation of respective chlorophenols. Respiration studies revealed inducible nature of enzymes for break down of 2-Cba, 4-Cba benzoic acid, 4-hydroxybenzoic acid and catechol. Extraction of plasmid DNA from parent strains showed presence of plasmid of same size in both strains. Cured strains showed absence of corresponding plasmid DNA bands thus indicating plasmid-borne genes for degradation of chlorobenzoates.

  4. Study on Antibiotic compounds from Pseudomonas aeruginosa NO4 Strain

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ji Young; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2011-05-15

    As important human and veterinary medicines, antibiotics are being produced and consumed in large quantities around the world. For example, more than 50 million pounds (22,000 tons) of antibiotics are produced in the U.S. each year and annual production in Germany is about 2,000 tons. Antibiotics are low molecular weight microbial metabolites that at low concentrations inhibit the growth of other microorganisms. Resistant bacteria may also spread and become broader infection-control problems, not only within health care institutions, but in communities as well. Clinically important bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA). MRSA is a common cause of infection among hospitalized patients. Pseudomonas aeruginosa is a major cause of opportunistic infections among immunocompromised individuals. The spread of this organism in health care settings is often difficult to control due to the presence of multiple intrinsic and acquired mechanisms of antimicrobial resistance. In this study, we isolated novel bacterium which had strong antagonistic activity and separated antibiotic compounds from Pseudomonas sp., and analyzed characteristics and molecular weight of the antibiotic compound

  5. Enterobacteria secrete an inhibitor of Pseudomonas virulence during clinical bacteriuria.

    Science.gov (United States)

    Ohlemacher, Shannon I; Giblin, Daryl E; d'Avignon, D André; Stapleton, Ann E; Trautner, Barbara W; Henderson, Jeffrey P

    2017-11-01

    Escherichia coli and other Enterobacteriaceae are among the most common pathogens of the human urinary tract. Among the genetic gains of function associated with urinary E. coli isolates is the Yersinia high pathogenicity island (HPI), which directs the biosynthesis of yersiniabactin (Ybt), a virulence-associated metallophore. Using a metabolomics approach, we found that E. coli and other Enterobacteriaceae expressing the Yersinia HPI also secrete escherichelin, a second metallophore whose chemical structure matches a known synthetic inhibitor of the virulence-associated pyochelin siderophore system in Pseudomonas aeruginosa. We detected escherichelin during clinical E. coli urinary tract infection (UTI) and experimental human colonization with a commensal, potentially probiotic E. coli bacteriuria strain. Escherichelin production by colonizing enterobacteria may help human hosts resist opportunistic infections by Pseudomonas and other pyochelin-expressing bacteria. This siderophore-based mechanism of microbial antagonism may be one of many elements contributing to the protective effects of the human microbiome. Future UTI-preventive probiotic strains may benefit by retaining the escherichelin biosynthetic capacity of the Yersinia HPI while eliminating the Ybt biosynthetic capacity.

  6. Reduction of PCN biosynthesis by NO in Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Lei Gao

    2016-08-01

    Full Text Available Pyocyanin (PCN, a virulence factor synthesized by Pseudomonas aeruginosa, plays an important role during clinical infections. There is no study of the effect of nitric oxide (NO on PCN biosynthesis. Here, the effect of NO on PCN levels in Pseudomonas aeruginosa strain PAO1, a common reference strain, was tested. The results showed that the NO donor sodium nitroprusside (SNP can significantly reduce PCN levels (82.5% reduction at 60 μM SNP. Furthermore, the effect of endogenous NO on PCN was tested by constructing PAO1 nor (NO reductase gene knockout mutants. Compared to the wild-type strain, the Δnor strain had a lower PCN (86% reduction in Δnor. To examine whether the results were universal with other P. aeruginosa strains, we collected 4 clinical strains from a hospital, tested their PCN levels after SNP treatment, and obtained similar results, i.e., PCN biosynthesis was inhibited by NO. These results suggest that NO treatment may be a new strategy to inhibit PCN biosynthesis and could provide novel insights into eliminating P. aeruginosa virulence as a clinical goal.

  7. Functional study of elafin cleaved by Pseudomonas aeruginosa metalloproteinases.

    LENUS (Irish Health Repository)

    Guyot, Nicolas

    2010-06-01

    Elafin is a 6-kDa innate immune protein present at several epithelial surfaces including the pulmonary epithelium. It is a canonical protease inhibitor of two neutrophil serine proteases [neutrophil elastase (NE) and proteinase 3] with the capacity to covalently bind extracellular matrix proteins by transglutamination. In addition to these properties, elafin also possesses antimicrobial and immunomodulatory activities. The aim of the present study was to investigate the effect of Pseudomonas aeruginosa proteases on elafin function. We found that P. aeruginosa PAO1-conditioned medium and two purified Pseudomonas metalloproteases, pseudolysin (elastase) and aeruginolysin (alkaline protease), are able to cleave recombinant elafin. Pseudolysin was shown to inactivate the anti-NE activity of elafin by cleaving its protease-binding loop. Interestingly, antibacterial properties of elafin against PAO1 were found to be unaffected after pseudolysin treatment. In contrast to pseudolysin, aeruginolysin failed to inactivate the inhibitory properties of elafin against NE. Aeruginolysin cleaves elafin at the amino-terminal Lys6-Gly7 peptide bond, resulting in a decreased ability to covalently bind purified fibronectin following transglutaminase activity. In conclusion, this study provides evidence that elafin is susceptible to proteolytic cleavage at alternative sites by P. aeruginosa metalloproteinases, which can affect different biological functions of elafin.

  8. Influence of Pseudomonas aeruginosa on exacerbation in patients with bronchiectasis

    Directory of Open Access Journals (Sweden)

    Kiran Chawla

    2015-01-01

    Full Text Available Background: A majority of the studies done on the western population have shown that Pseudomonas aeruginosa causes many severe infections in patients with bronchiectasis as compared to other pathogens. There is scarcity of similar data from the Asian population. Materials and Methods: A prospective study was undertaken to identify the various pathogens isolated from the respiratory samples of 117 patients with bronchiectasis from south India and to compare the clinicomicrobiological profile of infections caused by P. aeruginosa and other respiratory pathogens. Results: The respiratory pathogens were isolated from 63 (53.8% patients. P. aeruginosa was the most common isolate (46.0% followed by Klebsiella pneumoniae (14.3% and other pathogenic bacteria. Patients included in the P. aeruginosa group had a higher number of exacerbations (p: 0.008, greater number of hospital admissions (p: 0.007, a prolonged hospital stay (p: 0.03, and poor lung function, compared to the patients infected with the non-Pseudomonas group. Conclusion: It is necessary to investigate the etiology of respiratory tract infections among bronchiectasis patients followed by the prompt management of cases diagnosed with P. aeruginosa infections, so as to lower the morbidity and have a better prognosis.

  9. Crestamento bacteriano em filodendro causado por Pseudomonas cichorií.

    Directory of Open Access Journals (Sweden)

    Valdemar A. Malavolta Júnior

    2001-05-01

    Full Text Available É descrita a ocorrência de Pseudomonas cichorii causando lesões foliares ligeiramente circulares e de tamanho variável, em plantas de diversos cultivares de filodendro (Philodendron spp., provenientes de viveiro comercial localizado no município de Holambra (SP, e cultivados sob cobertura plástica. Essas manchas, pardo-escuras, podiam atingir até 7 a 8 cm de diâmetro, verificando-se, em alguns casos, coalescência de lesões, acarretando intenso crestamento foliar. Essa é a primeira constatação de Pseudomonas cichorii em filodendro no Brasil. Isolados encontram-se depositados na Coleção de Culturas do Instituto Biológico, Seção de Bacteriologia Fitopatológica (IBSBF sob n.ºs 1262 e 1263. Diferentes graus de resistência foram observados entre os cultivares de filodendro. O ‘Amarelo’ foi o mais resistente, enquanto P. scandens e os cultivares Boulevard e Red Emerald, além de quatro outros não identificados, mostraram alta suscetibilidade.

  10. Mutations in the DNA-binding domain of NR2E3 affect in vivo dimerization and interaction with CRX.

    Directory of Open Access Journals (Sweden)

    Raphael Roduit

    Full Text Available BACKGROUND: NR2E3 (PNR is an orphan nuclear receptor essential for proper photoreceptor determination and differentiation. In humans, mutations in NR2E3 have been associated with the recessively inherited enhanced short wavelength sensitive (S- cone syndrome (ESCS and, more recently, with autosomal dominant retinitis pigmentosa (adRP. NR2E3 acts as a suppressor of the cone generation program in late mitotic retinal progenitor cells. In adult rod photoreceptors, NR2E3 represses cone-specific gene expression and acts in concert with the transcription factors CRX and NRL to activate rod-specific genes. NR2E3 and CRX have been shown to physically interact in vitro through their respective DNA-binding domains (DBD. The DBD also contributes to homo- and heterodimerization of nuclear receptors. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed NR2E3 homodimerization and NR2E3/CRX complex formation in an in vivo situation by Bioluminescence Resonance Energy Transfer (BRET(2. NR2E3 wild-type protein formed homodimers in transiently transfected HEK293T cells. NR2E3 homodimerization was impaired in presence of disease-causing mutations in the DBD, except for the p.R76Q and p.R104W mutant proteins. Strikingly, the adRP-linked p.G56R mutant protein interacted with CRX with a similar efficiency to that of NR2E3 wild-type and p.R311Q proteins. In contrast, all other NR2E3 DBD-mutant proteins did not interact with CRX. The p.G56R mutant protein was also more effective in abolishing the potentiation of rhodospin gene transactivation by the NR2E3 wild-type protein. In addition, the p.G56R mutant enhanced the transrepression of the M- and S-opsin promoter, while all other NR2E3 DBD-mutants did not. CONCLUSIONS/SIGNIFICANCE: These results suggest different disease mechanisms in adRP- and ESCS-patients carrying NR2E3 mutations. Titration of CRX by the p.G56R mutant protein acting as a repressor in trans may account for the severe clinical phenotype in adRP patients.

  11. Localization of an Aldo-Keto Reductase (AKR2E4) in the Silkworm Bombyx mori (Lepidoptera: Bombycidae).

    Science.gov (United States)

    Yamamoto, K; Ozakiya, Y; Uno, T

    2017-09-01

    The aldo-keto reductase AKR2E4 reduces 3-dehydroecdysone to ecdysone in the silkworm Bombyx mori L. In this study, a quantitative polymerase chain reaction analysis revealed that the level of AKR2E4 mRNA was higher in the testes than in other tissues, and a western immunoblot analysis revealed that the AKR2E4 content in the testes was stage-specific from the fifth larval instar to the pupal stage. Immunohistochemical analysis showed that the AKR2E4 protein was present in cyst cells associated with sperm cells and spermatocytes. These results indicate that AKR2E4 plays an important role in 3-dehydroecdysone conversion to ecdysone and spermatogenesis in silkworm testes. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  12. Effects of ethanol on CYP2E1 levels and related oxidative stress using a standard balanced diet.

    Science.gov (United States)

    Azzalis, Ligia A; Fonseca, Fernando L A; Simon, Karin A; Schindler, Fernanda; Giavarotti, Leandro; Monteiro, Hugo P; Videla, Luis A; Junqueira, Virgínia B C

    2012-07-01

    Expression of cytochrome P4502E1 (CYP2E1) is very much influenced by nutritional factors, especially carbohydrate consumption, and various results concerning the expression of CYP2E1 were obtained with a low-carbohydrate diet. This study describes the effects of ethanol treatment on CYP2E1 levels and its relationship with oxidative stress using a balanced standard diet to avoid low or high carbohydrate consumption. Rats were fed for 1, 2, 3, or 4 weeks a commercial diet plus an ethanol-sucrose solution. The results have shown that ethanol administration was associated with CYP2E1 induction and stabilization without related oxidative stress. Our findings suggest that experimental models with a low-carbohydrate/high-fat diet produce some undesirable CYP2E1 changes that are not present when a balanced standard diet is given.

  13. Assessment of neutron skyshine near unmodified Accumulator Debuncher storage rings under Mu2e operational conditions

    Energy Technology Data Exchange (ETDEWEB)

    Cossairt, J.Donald; /Fermilab

    2010-12-01

    Preliminary plans for providing the proton beam needed by the proposed Mu2e experiment at Fermilab will require the transport of 8 GeV protons to the Accumulator/Debuncher where they be processed into an intensity and time structure useful for the experiment. The intensities involved are far greater that those encountered with antiprotons of the same kinetic energy in the same beam enclosures under Tevatron Collider operational conditions, the operating parameters for which the physical facilities of the Antiproton Source were designed. This note explores some important ramifications of the proposed operation for radiation safety and demonstrates the need for extensive modifications of significant portions of the shielding of the Accumulator Debuncher storage rings; notably that underneath the AP Service Buildings AP10, AP30, and AP50. While existing shielding is adequate for the current operating mode of the Accumulator/Debuncher as part of the Antiproton Source used in the Tevatron Collider program, without significant modifications of the shielding configuration in the Accumulator/Debuncher region and/or beam loss control systems far more effective than seen in most applications at Fermilab, the proposed operational mode for Mu2e is not viable for the following reasons: 1. Due to skyshine alone, under normal operational conditions large areas of the Fermilab site would be exposed to unacceptable levels of radiation where most of the Laboratory workforce and some members of the general public who regularly visit Fermilab would receive measurable doses annually, contrary to workforce, public, and DOE expectations concerning the As Low as Reasonably Achievable (ALARA) principle. 2. Under normal operational conditions, a sizeable region of the Fermilab site would also require fencing due to skyshine. The size of the areas involved would likely invite public inquiry about the significant and visible enlargement of Fermilab's posted radiological areas. 3. There

  14. M2e-tetramer-specific memory CD4 T cells are broadly protective against influenza infection.

    Science.gov (United States)

    Eliasson, D G; Omokanye, A; Schön, K; Wenzel, U A; Bernasconi, V; Bemark, M; Kolpe, A; El Bakkouri, K; Ysenbaert, T; Deng, L; Fiers, W; Saelens, X; Lycke, N

    2018-01-01

    Matrix protein 2 ectodomain (M2e) is considered an attractive component of a broadly protective, universal influenza A vaccine. Here we challenge the canonical view that antibodies against M2e are the prime effectors of protection. Intranasal immunizations of Balb/c mice with CTA1-3M2e-DD-generated M2e-specific memory CD4 T cells that were I-A d restricted and critically protected against infection, even in the complete absence of antibodies, as observed in JhD mice. Whereas some M2e-tetramer-specific memory CD4 T cells resided in spleen and lymph nodes, the majority were lung-resident Th17 cells, that rapidly expanded upon a viral challenge infection. Indeed, immunized IL-17A -/- mice were significantly less well protected compared with wild-type mice despite exhibiting comparable antibody levels. Similarly, poor protection was also observed in congenic Balb/B (H-2 b ) mice, which failed to develop M2e-specific CD4 T cells, but exhibited comparable antibody levels. Lung-resident CD69 + CD103 low M2e-specific memory CD4 T cells were αβ TCR + and 50% were Th17 cells that were associated with an early influx of neutrophils after virus challenge. Adoptively transferred M2e memory CD4 T cells were strong helper T cells, which accelerated M2e- but more importantly also hemagglutinin-specific IgG production. Thus, for the first time we demonstrate that M2e-specific memory CD4 T cells are broadly protective.

  15. Induction de la resistance au fletrissement bacterien du a Pseudomonas solanacearum E F Smith chez un cultivar de tomate repute sensible

    OpenAIRE

    Prior, Philippe; Beramis, M.

    1990-01-01

    Pseudomonas solanacearum est apporté à un sol amendé (750 unités N ha-1) avec de l’urée ou de la matière organique (farine de soja, boues de station d’épuration). Le flétrissement d’un cultivar de tomate très sensible (Floradel) est noté au cours de 3 cultures successives. On constate que la mortalité due à P solanacearum augmente régulièrement (14, 24 et 43%) dans le sol témoin non amendé, alors qu’elle est stable après traitement à l’urée (22, 15 et 26%) et nulle dès la 2e culture aprè...

  16. Induction of Callose Deposition in Tobacco (Nicotiana tabacum by Bacterial Lipopolysaccharide Pseudomonas syringae pv. tabaci and Pseudomonas syringae pv. glycinea

    Directory of Open Access Journals (Sweden)

    Pipit Marianingsih

    2014-12-01

    Full Text Available Lipopolysaccharide (LPS is a major component of outer-membrane gram-negative bacteria, and it can act as a Pathogen-Associated Molecular Pattern (PAMP for perception of pathogens by plants. LPS can be recognized by plants, triggering certain plant defense-related responses, including callose deposition. This study investigated induction of callose deposition by bacterial LPS in tobacco. Tobacco leaves were infiltrated with 400 μg/mL and 800 μg/mL LPS extracted from Pseudomonas syringae pv. tabaci (Pta and Pseudomonas syringae pv. glycinea (Pgl and incubated for 24 h or 48 h. To detect callose deposition, tobacco leaves were cleared in lactophenol solution, stained with aniline blue, and visualized by fluorescence microscopy. Results showed that LPS from Pgl induced more callose deposition in tobacco leaves than did that from Pta. In addition, a Pearson correlation test revealed that incubation period was the most significant factor in callose deposition, followed by the type of LPS bacteria. However, LPS concentration was not significantly corelated to callose deposition in tobacco leaves.

  17. Event display of a H -> 2e2mu candidate event

    CERN Multimedia

    ATLAS, Collaboration

    2012-01-01

    Event display of a H -> 2e2mu candidate event with m(4l) = 122.6 (123.9) GeV without (with) Z mass constraint. The masses of the lepton pairs are 87.9 GeV and 19.6 GeV. The event was recorded by ATLAS on 18-Jun-2012, 11:07:47 CEST in run number 205113 as event number 12611816. Muon tracks are colored red, electron tracks and clusters in the LAr calorimeter are colored green. The larger inset shows a zoom into the tracking detector. The smaller inset shows a zoom into the vertex region, indicating that the 4 leptons originate from the same primary vertex.

  18. Measurement of Time Resolution of the Mu2e LYSO Calorimeter Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Atanov, N. [Jouint Inst. of Nuclear Research, Dubna (Russia); et al.

    2015-09-16

    In this paper we present the time resolution measurements of the LutetiumYttrium Oxyorthosilicate (LYSO) calorimeter prototype for the Mu2e experiment. The measurements have been performed using the e- beam of the Beam Test Facility (BTF) in Frascati, Italy in the energy range from 100 to 400 MeV. The calorimeter prototype consisted of twenty five 30x30x130 mm3, LYSO crystals read out by 10x10 mm2 Hamamatsu Avalanche Photodiodes (APDs). The energy dependence of the measured time resolution can be parametrized as σt(E) = a/pE/GeV⊕b, with the stochastic and constant terms a = (51±1) ps and b = (14 ± 1) ps, respectively. This corresponds to the time resolution of (162 ± 3) ps at 100 MeV.

  19. Out-of-Time Beam Extinction in the MU2E Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Prebys, E. J. [Fermilab; Werkema, S. [Fermilab

    2015-06-01

    The Mu2e Experiment at Fermilab will search for the conversion of a muon to an electron in the field of an atomic nucleus with unprecedented sensitivity. The experiment requires a beam consisting of proton bunches 250 ns FW long, separated by 1.7 $\\mu$ sec, with no out-of-time protons at the $10^{10}$ fractional level. Satisfying this "extinction" requirement is very challenging. The formation of the bunches is expected to result in an extinction on the order of $10^5$. The remaining extinction will be accomplished by a system of resonant magnets and collimators, configured such that only in-time beam is delivered to the experiment. Our simulations show that the total extinction achievable by the system is on the order of $10^{12}$, with an efficiency for transmitting in-time beam of 99.6%.

  20. An energetic (e, 2e) reaction away from the Bethe ridge: recoil versus binary

    Energy Technology Data Exchange (ETDEWEB)

    Kheifets, A S [Research School of Physics, Australian National University, Canberra ACT 0200 (Australia); Naja, A; Casagrande, E M Staicu; Lahmam-Bennani, A, E-mail: A.Kheifets@anu.edu.a [Universite Paris-Sud 11, Laboratoire des Collisions Atomiques et Moleculaires, 91405 Orsay Cedex (France)

    2009-08-28

    We analyse the recoil-to-binary (RB) peak intensity ratio in an energetic (e, 2e) reaction performed on the valence ns sub-shell of noble gas atoms away from the Bethe ridge condition. A qualitative change in the RB ratio dependence on the ejected electron energy from He to Ar can be explained by the variation of reflectivity of the short-range Hartree-Fock potential. The reflectivity increases profoundly from lighter (He) to heavier (Ne and Ar) noble gas atoms because of modification of the scattering phases due to occupation of the target p orbitals (Levinson-Seaton theorem). This effect is further modified due to strong inter-shell correlations in Ar. These theoretical predictions are confirmed experimentally.

  1. A Case of Blau Syndrome with NOD2 E383K Mutation.

    Science.gov (United States)

    Harada, Jun; Nakajima, Takeshi; Kanazawa, Nobuo

    2016-11-01

    We report a 3.5-year-old Japanese boy who developed lichenoid papules and erythema with noncaseating epithelioid cell granulomas with a scant lymphocytic infiltrate histologically on his limbs at the age of 8 months. Genetic analysis of the patient and his parents, who had no medical past history, revealed heterozygous 1147G>A (E383K) mutation of NOD2 in the patient and in his father, so the patient was diagnosed with Blau syndrome and his father as an asymptomatic carrier. Although Blau syndrome has been reported as a genetic disease with high penetrance, asymptomatic carrier cases of a family with the same E383K mutation have also been reported. These results suggest that some contributing factors are required for the development of inflammatory and granulomatous responses in heterozygous carriers of a NOD2 E383K mutation. © 2016 Wiley Periodicals, Inc.

  2. Design, status and test of the Mu2e crystal calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Martini, Matteo; et al.

    2016-06-17

    The Mu2e experiment at Fermilab searches for the charged-lepton flavor violating neutrino-less conversion of a negative muon into an electron in the field of a aluminum nucleus. The dynamic of such a process is well modeled by a two-body decay, resulting in a monoenergetic electron with an energy slightly below the muon rest mass (104.967 MeV). The calorimeter of this experiment plays an important role to provide excellent particle identification capabilities and an online trigger filter while aiding the track reconstruction capabilities. The baseline calorimeter configuration consists of two disks each made with about 700 undoped CsI crystals read out by two large area UV-extended Silicon Photomultipliers. These crystals match the requirements for stability of response, high resolution and radiation hardness. In this paper we present the final calorimeter design.

  3. Event display of a H -> 2e2mu candidate event

    CERN Multimedia

    ATLAS, Collaboration

    2012-01-01

    Event display of a H -> 2e2mu candidate event with m(4l) = 122.6 (123.9) GeV without (with) Z mass constraint. The masses of the lepton pairs are 87.9 GeV and 19.6 GeV. The event was recorded by ATLAS on 18-Jun-2012, 11:07:47 CEST in run number 205113 as event number 12611816. Muon tracks are colored red, electron tracks and clusters in the LAr calorimeter are colored green. The Lego plot inset indicates the amount of transverse energy Et measured in the calorimeters. The second inset shows a zoom into the vertex region, indicating that the 4 leptons originate from the same primary vertex.

  4. Book Review: Professional Penetration Testing: Creating and Learning in a Hacking Lab 2E

    Directory of Open Access Journals (Sweden)

    Joshua Bartolomie

    2013-09-01

    Full Text Available Wilhelm, T. (2013. Professional Penetration Testing: Creating and Learning in a Hacking Lab 2E. Waltham, MA: Syngress, 464 pages, ISBN-10: 1597499935; ISBN-13: 978-1597499934, US$79.99Reviewed by Joshua Bartolomie, CISSP, CEECS, CFCE, DFCP, CRISC, CSMOrganizations often strive for proactive information security programs in an effort to limit occurrence and impact of security breaches. However, traditional security programs run the risk of being unable to provide adequate insight and proactive awareness into real attack vectors that may exist within their organizations. With attack methods and efforts becoming increasingly aggressive, and effective, organizations must take equally assertive measures to protect their critical information and assets. Penetration testing is one of those tools that is often misunderstood, overlooked, and undervalued. A true adversary would not hesitate to exploit every potential to gain entry or cause a disruption to their target.(see PDF for full review

  5. Dynamical (e,2e) studies of tetrahydropyran and 1,4-dioxane

    Energy Technology Data Exchange (ETDEWEB)

    Builth-Williams, J. D.; Chiari, L.; Jones, D. B., E-mail: darryl.jones@flinders.edu.au, E-mail: michael.brunger@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Silva, G. B. da [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Universidade Federal de Mato Grosso, Barra do Garças, MT 78600-000 (Brazil); Chaluvadi, Hari; Madison, D. H. [Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409 (United States); Brunger, M. J., E-mail: darryl.jones@flinders.edu.au, E-mail: michael.brunger@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2014-06-07

    We present experimental and theoretical results for the electron-impact ionization of the highest occupied molecular orbitals of tetrahydropyran and 1,4-dioxane. Using an (e,2e) technique in asymmetric coplanar kinematics, angular distributions of the slow ejected electron, with an energy of 20 eV, are measured when incident electrons at 250 eV ionize the target and scatter through an angle of either −10° or −15°. The data are compared with calculations performed at the molecular 3-body distorted wave level. Fair agreement between the theoretical model and the experimental measurements was observed. The similar structures for these targets provide key insights for assessing the limitations of the theoretical calculations. This study in turn facilitates an improved understanding of the dynamics in the ionization process.

  6. The molecular mechanism regulating 24-hour rhythm of CYP2E1 expression in the mouse liver.

    Science.gov (United States)

    Matsunaga, Naoya; Ikeda, Misaki; Takiguchi, Takako; Koyanagi, Satoru; Ohdo, Shigehiro

    2008-07-01

    Cytochrome P450 2E1 (CYP2E1) is clinically and toxicologically important and exhibits 24-hour periodicity in its activity. In the present study, we investigated whether hepatic nuclear factor-1alpha (HNF-1alpha) and clock genes with a striking 24-hour rhythm in mouse liver contributed to the 24-hour regulation of CYP2E1 expression. The results demonstrated that the expression of CYP2E1 messenger RNA (mRNA) in the liver was affected by HNF-1alpha and the circadian organization of molecular clocks. The mRNA levels of CYP2E1 in the liver increased from the late light phase to the early dark phase. Luciferase reporter gene analysis revealed that HNF-1alpha activated CYP2E1 promoter activity, which was restricted by CRY1, a member of the circadian organization of molecular clocks. Repressor activity of CRY1 was observed on the HNF-1alpha binding site of the CYP2E1 promoter region with mutated E-box. Serum shock induced approximately 24-hour oscillation in CYP2E1 mRNA in HepG2. Transfection of HNF-1alpha and CRY1 small interfering RNA dampened the oscillation of CYP2E1 mRNA in HepG2. Chromatin immunoprecipitation assay in the CYP2E1 promoter indicated that HNF-1alpha binding to the CYP2E1 promoter increased from the late light phase to the early dark phase. Using the chromatin immunoprecipitation reimmunoprecipitation assay, time-dependent differences were demonstrated for CRY1 protein interaction with HNF-1alpha transcriptional complexes, including coactivator p300 on the HNF-1alpha binding site in the CYP2E1 promoter. Our results suggest that the transcription activator of HNF-1alpha acts periodically and the negative limbs of molecular clocks periodically inhibit CYP2E1 transcription, resulting in the 24-hour rhythm of its mRNA expression.

  7. HBx inhibits CYP2E1 gene expression via downregulating HNF4α in human hepatoma cells.

    Directory of Open Access Journals (Sweden)

    Hongming Liu

    Full Text Available CYP2E1, one of the cytochrome P450 mixed-function oxidases located predominantly in liver, plays a key role in metabolism of xenobiotics including ethanol and procarcinogens. Recently, down-expression of CYP2E1 was found in hepatocellular carcinoma (HCC with the majority to be chronic hepatitis B virus (HBV carriers. In this study, we tested a hypothesis that HBx may inhibit CYP2E1 gene expression via hepatocyte nuclear factor 4α (HNF4α. By enforced HBx gene expression in cultured HepG2 cells, we determined the effect of HBx on CYP2E1 mRNA and protein expression. With a bioinformatics analysis, we found a consensus HNF-4α binding sequence located on -318 to -294 bp upstream of human CYP2E1 promoter. Using reporter gene assay and site-directed mutagenesis, we have shown that mutation of this site dramatically decreased CYP2E1 promoter activity. By silencing endogenous HNF-4α, we have further validated knockdown of HNF-4α significantly decreased CYP2E1 expression. Ectopic overexpression of HBx in HepG2 cells inhibits HNF-4α expression, and HNF-4α levels were inversely correlated with viral proteins both in HBV-infected HepG2215 cells and as well as HBV positive HCC liver tissues. Moreover, the HBx-induced CYP2E1 reduction could be rescued by ectopic supplement of HNF4α protein expression. Furthermore, human hepatoma cells C34, which do not express CYP2E1, shows enhanced cell growth rate compared to E47, which constitutively expresses CYP2E1. In addition, the significantly altered liver proteins in CYP2E1 knockout mice were detected with proteomics analysis. Together, HBx inhibits human CYP2E1 gene expression via downregulating HNF4α which contributes to promotion of human hepatoma cell growth. The elucidation of a HBx-HNF4α-CYP2E1 pathway provides novel insight into the molecular mechanism underlining chronic HBV infection associated hepatocarcinogenesis.

  8. Ferric Uptake Regulator Fur Is Conditionally Essential in Pseudomonas aeruginosa.

    Science.gov (United States)

    Pasqua, Martina; Visaggio, Daniela; Lo Sciuto, Alessandra; Genah, Shirley; Banin, Ehud; Visca, Paolo; Imperi, Francesco

    2017-11-15

    In Pseudomonas aeruginosa, the ferric uptake regulator (Fur) protein controls both metabolism and virulence in response to iron availability. Differently from other bacteria, attempts to obtain fur deletion mutants of P. aeruginosa failed, leading to the assumption that Fur is an essential protein in this bacterium. By investigating a P. aeruginosa conditional fur mutant, we demonstrate that Fur is not essential for P. aeruginosa growth in liquid media, biofilm formation, and pathogenicity in an insect model of infection. Conversely, Fur is essential for growth on solid media since Fur-depleted cells are severely impaired in colony formation. Transposon-mediated random mutagenesis experiments identified pyochelin siderophore biosynthesis as a major cause of the colony growth defect of the conditional fur mutant, and deletion mutagenesis confirmed this evidence. Impaired colony growth of pyochelin-proficient Fur-depleted cells does not depend on oxidative stress, since Fur-depleted cells do not accumulate higher levels of reactive oxygen species (ROS) and are not rescued by antioxidant agents or overexpression of ROS-detoxifying enzymes. Ectopic expression of pch genes revealed that pyochelin production has no inhibitory effects on a fur deletion mutant of Pseudomonas syringae pv. tabaci, suggesting that the toxicity of the pch locus in Fur-depleted cells involves a P. aeruginosa-specific pathway(s).IMPORTANCE Members of the ferric uptake regulator (Fur) protein family are bacterial transcriptional repressors that control iron uptake and storage in response to iron availability, thereby playing a crucial role in the maintenance of iron homeostasis. While fur null mutants of many bacteria have been obtained, Fur appears to be essential in Pseudomonas aeruginosa for still unknown reasons. We obtained Fur-depleted P. aeruginosa cells by conditional mutagenesis and showed that Fur is dispensable for planktonic growth, while it is required for colony formation. This is

  9. Adherence of Pseudomonas aeruginosa onto surfactant-laden contact lenses.

    Science.gov (United States)

    Mosuela, Reynalyn; Mustafa, Shelan; Gould, Simon; Hassanin, Hany; Alany, Raid G; ElShaer, Amr

    2018-03-01

    There is an immense research interest to utilise contact lens (CLs) as a popular platform for ocular drug delivery. However, CLs are the major predisposing factors of bacterial keratitis which is commonly caused by adhesion of microbes such as Pseudomonas aeruginosa and Staphylococcus epidermidis. The aim of the current study is to explore the effect of surfactants; Poloxamer 188, Polysorbate 80 and Tetronic ® 90R4 (at 0.25% - 3% v/v) on the characteristics of CLs and on the adhesion abilities of Pseudomonas aeruginosa to the lenses' surfaces. CLs were formulated using a hydrophilic monomer; 2-hydroxyethyl methacrylate (HEMA) together with silicone-based polymer such as Poly dimethyl siloxane (PDMS) or 3,3,3-trifluoropropylsilane (FSA) then lenses were polymerized under UV light. The formulated CLs with surfactants were found to have an increased equilibrium water content (EWC) due to hydrophilic moiety present in surfactants. A relationship was deduced between EWC and surface contact angle of lenses containing surfactants; where an increased EWC was associated with a decrease in contact angle reflecting a more hydrophilic surfaces of CLs. Apart from the 3% Polysorbate 80 (p Lenses with surfactants were found to have lower bacterial ATP concentration than lenses without surfactants. Poloxamer 188 in FSA lenses reduced bacterial adhesion from 4.22 × 10 -4  ± 1.30 × 10 -4 pM to 1.03 × 10 -4  ± 4.86 × 10 -5 pM, a reduction by 75.59% when compared to the control lenses (p = .002). Moreover, 1% Tetronic ® 90R4 in PDMS showed a reduction by 57.17% in ATP concentration. Polysorbate 80 in FSA exhibited the least bacterial adhesion with an average bacterial ATP concentration of 3.85 × 10 -5  ± 2.61 × 10 -5 pM; i.e 90.88% less bacterial ATP than control lenses (p = .001). Bioluminescence studies demonstrated a decrease in Pseudomonas aeruginosa adhesion to CLs containing surfactants without impairing the optical and

  10. Inhibition of Cell Differentiation in Bacillus subtilis by Pseudomonas protegens

    Science.gov (United States)

    Powers, Matthew J.; Sanabria-Valentín, Edgardo; Bowers, Albert A.

    2015-01-01

    ABSTRACT Interspecies interactions have been described for numerous bacterial systems, leading to the identification of chemical compounds that impact bacterial physiology and differentiation for processes such as biofilm formation. Here, we identified soil microbes that inhibit biofilm formation and sporulation in the common soil bacterium Bacillus subtilis. We did so by creating a reporter strain that fluoresces when the transcription of a biofilm-specific gene is repressed. Using this reporter in a coculture screen, we identified Pseudomonas putida and Pseudomonas protegens as bacteria that secrete compounds that inhibit biofilm gene expression in B. subtilis. The active compound produced by P. protegens was identified as the antibiotic and antifungal molecule 2,4-diacetylphloroglucinol (DAPG). Colonies of B. subtilis grown adjacent to a DAPG-producing P. protegens strain had altered colony morphologies relative to B. subtilis colonies grown next to a DAPG-null P. protegens strain (phlD strain). Using a subinhibitory concentration of purified DAPG in a pellicle assay, we saw that biofilm-specific gene transcription was delayed relative to transcription in untreated samples. These transcriptional changes also corresponded to phenotypic alterations: both biofilm biomass and spore formation were reduced in B. subtilis liquid cultures treated with subinhibitory concentrations of DAPG. Our results add DAPG to the growing list of antibiotics that impact bacterial development and physiology at subinhibitory concentrations. These findings also demonstrate the utility of using coculture as a means to uncover chemically mediated interspecies interactions between bacteria. IMPORTANCE Biofilms are communities of bacteria adhered to surfaces by an extracellular matrix; such biofilms can have important effects in both clinical and agricultural settings. To identify chemical compounds that inhibited biofilm formation, we used a fluorescent reporter to screen for bacteria that

  11. Diversity of Pseudomonas Genomes, Including Populus-Associated Isolates, as Revealed by Comparative Genome Analysis

    Science.gov (United States)

    Jun, Se-Ran; Wassenaar, Trudy M.; Nookaew, Intawat; Hauser, Loren; Wanchai, Visanu; Land, Miriam; Timm, Collin M.; Lu, Tse-Yuan S.; Schadt, Christopher W.; Doktycz, Mitchel J.; Pelletier, Dale A.

    2015-01-01

    The Pseudomonas genus contains a metabolically versatile group of organisms that are known to occupy numerous ecological niches, including the rhizosphere and endosphere of many plants. Their diversity influences the phylogenetic diversity and heterogeneity of these communities. On the basis of average amino acid identity, comparative genome analysis of >1,000 Pseudomonas genomes, including 21 Pseudomonas strains isolated from the roots of native Populus deltoides (eastern cottonwood) trees resulted in consistent and robust genomic clusters with phylogenetic homogeneity. All Pseudomonas aeruginosa genomes clustered together, and these were clearly distinct from other Pseudomonas species groups on the basis of pangenome and core genome analyses. In contrast, the genomes of Pseudomonas fluorescens were organized into 20 distinct genomic clusters, representing enormous diversity and heterogeneity. Most of our 21 Populus-associated isolates formed three distinct subgroups within the major P. fluorescens group, supported by pathway profile analysis, while two isolates were more closely related to Pseudomonas chlororaphis and Pseudomonas putida. Genes specific to Populus-associated subgroups were identified. Genes specific to subgroup 1 include several sensory systems that act in two-component signal transduction, a TonB-dependent receptor, and a phosphorelay sensor. Genes specific to subgroup 2 contain hypothetical genes, and genes specific to subgroup 3 were annotated with hydrolase activity. This study justifies the need to sequence multiple isolates, especially from P. fluorescens, which displays the most genetic variation, in order to study functional capabilities from a pangenomic perspective. This information will prove useful when choosing Pseudomonas strains for use to promote growth and increase disease resistance in plants. PMID:26519390

  12. Hydrolytic potential of a psychrotrophic Pseudomonas isolated from refrigerated raw milk

    Directory of Open Access Journals (Sweden)

    Ana Paula F. Corrêa

    2011-12-01

    Full Text Available The production of extracellular hydrolases by a psychrotrophic bacterium isolated from refrigerated raw milk, and identified as a Pseudomonas sp. belonging to the Pseudomonas jenssenii group, was studied. This bacterium produced proteolytic and lipolytic enzymes in all media investigated (skim milk, cheese whey, casein broth, and tryptone soy broth. High levels of α-glucosidase were produced in skim milk broth. Hydrolytic enzymes detected in skim milk broth are of particular concern, indicating that these enzymes could be produced by Pseudomonas sp. during the cold storage of raw milk, contributing to the spoilage problem in milk and dairy products.

  13. Characteristics of Bacterial Strains from Pseudomonas Genera Isolated from Diseased Plum Trees

    Directory of Open Access Journals (Sweden)

    Veljko Gavrilović

    2008-01-01

    Full Text Available Characteristics of Pseudomonas syringae strains isolated from diseased plum trees are presented is this paper. Based on pathogenic, biochemical and physiological characteristics, isolated starins were divided into two groups: First group of strains, isolated from diseased plum branches with symptoms of suden decay, was simillar to Pseudomonas syringae pv. syringae; second group of strains, isolated from necrotic flower buds on plum trees, exhibited characteristics simillar to Pseudomonas syringae pv. morsprunorum. In addition, phytopathogenic fungi belonging to genera Phomopsis, Botryosphaeria and Leucostoma, were also isolated from diseased plum trees. Further study of these pathogens and their role in the epidemiology of suden plum trees decay is in progress.

  14. [Pseudomonas infection: biological risk by occupational exposure and results of an environmental monitoring].

    Science.gov (United States)

    Massoni, Francesco; Giorgi, Doriana Antonella; Palmieri, Sabina; Arcangeli, Luca; Ricci, Serafino

    2014-01-01

    The biological risk of Pseudomonas aeruginosa for activities involving exposure to contaminated water, such as, for example, routine maintenance of swimming pools, is related to the availability of effective prophylactic and therapeutic measures. The authors present the data of the microbiological analyzes made on 2349 samples taken from pools in Rome and province. The contamination by Pseudomonas was found in 191 samples with 13 samples that had a level > 100 cfu/100 ml and 5 samples with level > 200 cfu/100 ml. Useful considerations derived from the analysis of the literature about the profile and prophylactic treatment of infection by Pseudomonas, necessarily to be taken into consideration for an adequate risk assessment.

  15. Dynamics of sodium dodecyl sulfate utilization andantibiotic susceptibility of strain Pseudomonas sp. ATCC19151

    Directory of Open Access Journals (Sweden)

    Jovčić B.

    2009-01-01

    Full Text Available Pseudomonas sp. ATCC19151 harbors a gene encoding a putative alkylsulfatase (sdsA. Here we report a growth ability of this strain in minimal media containing 0.5, 0.75, and 1% sodium dodecyl sulfate as the sole carbon source. The most prominent growth was detected for the minimal medium with 0.5% SDS, so this concentration of SDS was used to monitor Pseudomonas sp. ATCC19151 SDS biodegradation dynamics. Bacterial growth coincided with the disappearance of SDS. Antibiotic susceptibility was tested as well. Pseudomonas sp. ATCC19151 was resistant to six out of nine tested antibiotics, including ampicillin, tetracycline, chloramphenicol, tobramycin, nalidixic acid, and gentamycin.

  16. Bioreporter pseudomonas fluorescens HK44 immobilized in a silica matrix

    Directory of Open Access Journals (Sweden)

    Trogl J.

    2003-01-01

    Full Text Available The bioluminescent bioreporter Pseudomonas fluorescens HK44, the whole cell bacterial biosensor that responds to naphthalene and its metabolites via the production of visible light, was immobilized into a silica matrix by the sol-gel technique. The bioluminescence intensities were measured in the maximum of the bioluminescence band at X = 500 nm. The immobilized cells (>105 cells per g silica matrix produced light after induction by salicylate (cone. > 10 g/l, naphthalene and aminobenzoic acid. The bioluminescence intensities induced by 2,3-dihydroxynaphthalene 3-hydroxybenzoic acid and 4-hydroxybenzoic acid were comparable to a negative control. The cells in the silica layers on glass slides produced light in response to the presence of an inductor at least 8 months after immobilization, and >50 induction cycles. The results showed that these test slides could be used as assays for the multiple determination of water pollution.

  17. Extracellular DNA Shields against Aminoglycosides in Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Chiang, Wen-Chi; Nilsson, Martin; Jensen, Peter Østrup

    2013-01-01

    Within recent years, it has been established that extracellular DNA is a key constituent of the matrix of microbial biofilms. In addition, it has recently been demonstrated that DNA binds positively charged antimicrobials such as aminoglycosides and antimicrobial peptides. In the present study, w...... that the aminoglycoside tolerance mediated by the presence of extracellular DNA is not caused by activation of the pmr genes in our P. aeruginosa biofilms but rather by a protective shield effect of the extracellular DNA....... provide evidence that extracellular DNA shields against aminoglycosides in Pseudomonas aeruginosa biofilms. We show that exogenously supplemented DNA integrates into P. aeruginosa biofilms and increases their tolerance toward aminoglycosides. We provide evidence that biofilms formed by a DNA release...

  18. Electrophoretic analysis of cyanide depletion by Pseudomonas alcaligenes.

    Science.gov (United States)

    Zaugg, S E; Davidson, R A; Walker, J C; Walker, E B

    1997-02-01

    Bacterial-facilitated depletion of cyanide is under development for remediation of heap leach operations in the gold mining industry. Capillary electrophoresis was found to be a powerful tool for quantifying cyanide depletion. Changes in cyanide concentration in aqueous suspensions of Pseudomonas alcaligenes bacteria and cyanide at elevated pH were easily monitored by capillary electrophoresis. The resulting data can be used to study rates of cyanide depletion by this strain of bacteria. Concentrations of these bacteria at 10(5) cells/mL were found to reduce cyanide from 100 ppm to less than 8 ppm in four days. In addition, other ions of interest in cyanide metabolism, such as formate, can be simultaneously analyzed. Direct UV detection of cyanide at 192 nm further simplifies the analytical method for these ions.

  19. Nitrite Formation from Hydroxylamine and Oximes by Pseudomonas aeruginosa

    Science.gov (United States)

    Amarger, Noelle; Alexander, M.

    1968-01-01

    Nitrite was formed from hydroxylamine and several oximes by intact cells and extracts of Pseudomonas aeruginosa. The activity was induced by the presence of oximes in the culture medium. Nitroalkanes were not intermediates in the conversion of acetaldoxime, acetone oxime, or butanone oxime to nitrite, since nitromethane inhibited the formation of nitrite from the nitro compounds but not from the corresponding oximes. The oxime apparently functions as a constant source of hydroxylamine during growth of the bacterium. Hydroxylamine at low concentration was converted stoichiometrically to nitrite by extracts of the bacterium; high concentrations were inhibitory. Nicotinamide adenine dinucleotide phosphate, oxygen, and other unidentified cofactors were necessary for the reaction. Actively nitrifying extracts possessed no hydroxylamine-cytochrome c reductase activity. Hyponitrite, nitrous oxide, and nitric oxide were not metabolized. PMID:4384968

  20. Mass Spectrometry Analysis of Pseudomonas aeruginosa Treated with Azithromycin

    Science.gov (United States)

    Phelan, Vanessa V.; Fang, Jinshu; Dorrestein, Pieter C.

    2015-06-01

    In microbiology, changes in specialized metabolite production (cell-to-cell signaling metabolites, virulence factors, and natural products) are measured using phenotypic assays. However, advances in mass spectrometry-based techniques including imaging mass spectrometry (IMS) now allow researchers to directly visualize the production of specialized metabolites from microbial colony biofilms. In this study, a combination of IMS and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to visualize the effect of the macrolide antibiotic azithromycin (AZM) on colony biofilms of Pseudomonas aeruginosa. Although previous research suggested that AZM may inhibit cell-to-cell signaling of P. aeruginosa and thereby reduce pathogenicity, we observed no clear decrease in specialized metabolite production.

  1. The implication of Pseudomonas aeruginosa biofilms in infections

    DEFF Research Database (Denmark)

    Rybtke, Morten T; Jensen, Peter Østrup; Høiby, Niels

    2011-01-01

    Biofilm formation by bacteria is recognized as a major problem in chronic infections due to their recalcitrance against the immune defense and available antibiotic treatment schemes. The opportunistic pathogen Pseudomonas aeruginosa has drawn special attention in this regard due to its severity......-up of the extracellular matrix encasing the biofilm-associated bacteria as well as the elaborate signaling mechanisms employed by the bacterium enables it to withstand the continuous stresses imposed by the immune defense and administered antibiotics resulting in a state of chronic inflammation that damages the host....... The immune response leading to this chronic inflammation is described. Finally, novel treatment strategies against P. aeruginosa are described including, quorum-sensing inhibition and induced biofilm-dispersion. The tolerance towards currently available antimicrobials calls for development of alternative...

  2. Chemistry and biology of pyoverdines, Pseudomonas primary siderophores.

    Science.gov (United States)

    Cézard, C; Farvacques, N; Sonnet, P

    2015-01-01

    Pyoverdine is the generic name given to a vast family of fluorescent green-yellowish pigments produced by Pseudomonas species. Pseudomonas aeruginosa is an opportunistic pathogen, particularly infecting humans with compromised natural defenses. These infections result in significantly higher morbidity, longer hospitalization, increased mortality rates and excess health care costs. P. aeruginosa is very difficult to eradicate because of an intrinsic coupled with an adaptive resistance to a wide variety of classical antibiotics. When subjected to iron starvation conditions, Pseudomonas bacteria synthesize pyoverdines, their primary siderophores, to acquire iron from the extracellular medium. These molecules are not only powerful iron(III) scavengers but efficient iron(III) transporters as well. Three distinct structural parts constitute pyoverdines, i.e. (i) the fluorescent chromophore, deriving from a dihydroxyquinoline, attached via its carbonyl group to (ii) a type-specific peptide composed of 6 to 14 amino acids and (iii) a small side chain corresponding to a carboxylic acid derivative. Their chemical structure show three bidentate chelating sites including a catechol and two hydroxamates, leading to an octahedral geometry when complexed to iron(III). While the chromophore group is common to all pyoverdines, their peptide moiety differs among strains and species by the number, length, composition and configuration of amino acids. Following chelation with iron(III), the newly formed pyoverdine-Fe complex is recognized by a specific outer membrane transporter, namely FpvA, and reenters the cell where the iron is released from the pyoverdine into the periplasm for further incorporation into bacterial proteins. The remaining apo-pyoverdine is then recycled and secreted back to the extracellular medium by efflux pumps. Besides, the role of pyoverdines in P. aeruginosa is not only limited to scavenge iron from the bacterial environment. Indeed, these siderophores act

  3. Effects of ginseng on Pseudomonas aeruginosa motility and biofilm formation

    DEFF Research Database (Denmark)

    Wu, Hong; Lee, Baoleri; Yang, Liang

    2011-01-01

    Biofilm-associated chronic Pseudomonas aeruginosa lung infections in patients with cystic fibrosis are virtually impossible to eradicate with antibiotics because biofilm-growing bacteria are highly tolerant to antibiotics and host defense mechanisms. Previously, we found that ginseng treatments...... protected animal models from developing chronic lung infection by P. aeruginosa. In the present study, the effects of ginseng on the formation of P. aeruginosa biofilms were further investigated in vitro and in vivo. Ginseng aqueous extract at concentrations of 0.5-2.0% did not inhibit the growth of P....... aeruginosa, but significantly prevented P. aeruginosa from forming biofilm. Exposure to 0.5% ginseng aqueous extract for 24 h destroyed most 7-day-old mature biofilms formed by both mucoid and nonmucoid P. aeruginosa strains. Ginseng treatment enhanced swimming and twitching motility, but reduced swarming...

  4. Chronic Pseudomonas aeruginosa lung infection in normal and athymic rats

    DEFF Research Database (Denmark)

    Johansen, H K; Espersen, F; Pedersen, S S

    1993-01-01

    We have compared a chronic lung infection with Pseudomonas aeruginosa embedded in alginate beads in normal and athymic rats with an acute infection with free live P. aeruginosa bacteria. The following parameters were observed and described: mortality, macroscopic and microscopic pathologic changes......, and antibody responses. The rats challenged with P. aeruginosa alginate beads experienced a generally more severe lung pathology and the antibody responses were more homogeneous with less dispersion as compared to the rats having free live P. aeruginosa bacteria. In general, manifestations were more severe...... in the athymic rats compared to the normal rats. It is, however, notable that the athymic rats developed similar microscopic lung manifestations as the normal rats when given a large number of P. aeruginosa in the beads, with dense accumulation of neutrophil granulocytes and microcolonies comparable...

  5. Hyperbaric oxygen sensitizes anoxic Pseudomonas aeruginosa biofilm to ciprofloxacin

    DEFF Research Database (Denmark)

    Kolpen, Mette; Lerche, Christian J; Kragh, Kasper Nørskov

    2017-01-01

    Chronic Pseudomonas aeruginosa lung infection is characterized by the presence of endobronchial antibiotic-tolerant biofilm subject to strong oxygen (O2) depletion due to the activity of surrounding polymorphonuclear leukocytes. The exact mechanisms affecting the antibiotic susceptibility...... metabolism activity and the endogenous formation of reactive O2 radicals (ROS). In this study we aimed to apply hyperbaric oxygen treatment (HBOT) in order to sensitize anoxic P. aeruginosa agarose-biofilms established to mimic situations with intense O2 consumption by the host response in the cystic...... that oxygenation by HBOT improves the bactericidal activity of ciprofloxacin on P. aeruginosa biofilm and suggest that bacterial biofilms is sensitized to antibiotics by supplying hyperbaric O2....

  6. Pseudomonas aeruginosa PA14 pathogenesis in Caenorhabditis elegans.

    Science.gov (United States)

    Kirienko, Natalia V; Cezairliyan, Brent O; Ausubel, Frederick M; Powell, Jennifer R

    2014-01-01

    The nematode Caenorhabditis elegans is a simple model host for studying the interaction between bacterial pathogens such as Pseudomonas aeruginosa and the metazoan innate immune system. Powerful genetic and molecular tools in both C. elegans and P. aeruginosa facilitate the identification and analysis of bacterial virulence factors as well as host defense factors. Here we describe three different assays that use the C. elegans-P. aeruginosa strain PA14 host-pathogen system. Fast Killing is a toxin-mediated death that depends on a diffusible toxin produced by PA14 but not on live bacteria. Slow Killing is due to an active infection in which bacteria colonize the C. elegans intestinal lumen. Liquid Killing is designed for high-throughput screening of chemical libraries for anti-infective compounds. Each assay has unique features and, interestingly, the PA14 virulence factors involved in killing are different in each assay.

  7. Attenuation of Pseudomonas aeruginosa virulence by quorum sensing inhibitors

    DEFF Research Database (Denmark)

    Hentzer, Morten; Wu, Hong; Andersen, Jens Bo

    2003-01-01

    Traditional treatment of infectious diseases is based on compounds that kill or inhibit growth of bacteria. A major concern with this approach is the frequent development of resistance to antibiotics. The discovery of communication systems (quorum sensing systems) regulating bacterial virulence has...... afforded a novel opportunity to control infectious bacteria without interfering with growth. Compounds that can override communication signals have been found in the marine environment. Using Pseudomonas aeruginosa PAO1 as an example of an opportunistic human pathogen, we show that a synthetic derivate...... and inhibited virulence factor expression. Application of the drug to P.aeruginosa biofilms increased bacterial susceptibility to tobramycin and SDS. In a mouse pulmonary infection model, the drug inhibited quorum sensing of the infecting bacteria and promoted their clearance by the mouse immune response....

  8. [Effect on keratocyte-mediated collagen degradation by Pseudomonas aeruginosa].

    Science.gov (United States)

    Hao, J; Lu, Y; Jia, H; Liu, J; Xu, J; Zhang, R

    2000-01-01

    To study the pathogenesis of cornea melting (ulceration) by pseudomona (P) aeruginosa for instruction of clinical treatment. Type I collagen gels with or without suspended keratocytes were incubated for 24 hours under medium containing sterile P. aeruginosa culture broth. Native collagen fibrils were removed from the media by ultrafiltration. The ultrafiltrates were then hydrolyzed, and the amount of hydroxyproline was measured spectrophotometrically. The effect of a synthetic matrix metalloproteinase (MMP) inhibitor, Galardin, on collagen degradation was also examined. P. aeruginosa broth induced type I collagen gel degradation directly. In the presence of keratocytes, degradation by P. aeruginosa broth was enhanced. Galardin significantly reduced the amount of collagen degraded by P. aeruginosa culture broth, no matter keratocytes were present or not. P. aeruginosa culture broth directly degrades type I collagen and also increases keratocyte-mediated collagen degradation. The result is helpful to the clinical treatment of cornea melting caused by P. aeruginosa, and the mechanism should be further studied.

  9. Expanded bed adsorption of an alkaline lipase from Pseudomona cepacia.

    Science.gov (United States)

    da Silva Padilha, Giovana; Curvelo-Santana, José Carlos; Alegre, Ranulfo Monte; Tambourgi, Elias Basile

    2009-02-15

    An extracellular lipase was isolated from Pseudomona cepacia by expanded bed adsorption on an Amberlite 410 ion-exchange resin. Enzyme characterization and hydrodynamic study of a chromatography column were done. Enzyme purification was done at three condition of expanded bed height (H): at one and half (6cm), at two (8cm) and at three (12cm) times the fixed bed height (H(0)=4cm). The results showed that the experimental data was fitted to the Richardson and Zaki equation, and the comparison between the experimental and calculated terminal velocities showed low relative error. In enzyme purification for better condition, a purification factor of about 80 times was found at 6cm of expanded bed height, or 1.5 times of expansion degree. Purified lipase had an optimal pH and a temperature of 8 and 37 degrees C, respectively.

  10. Novel multiscale modeling tool applied to Pseudomonas aeruginosa biofilm formation.

    Directory of Open Access Journals (Sweden)

    Matthew B Biggs

    Full Text Available Multiscale modeling is used to represent biological systems with increasing frequency and success. Multiscale models are often hybrids of different modeling frameworks and programming languages. We present the MATLAB-NetLogo extension (MatNet as a novel tool for multiscale modeling. We demonstrate the utility of the tool with a multiscale model of Pseudomonas aeruginosa biofilm formation that incorporates both an agent-based model (ABM and constraint-based metabolic modeling. The hybrid model correctly recapitulates oxygen-limited biofilm metabolic activity and predicts increased growth rate via anaerobic respiration with the addition of nitrate to the growth media. In addition, a genome-wide survey of metabolic mutants and biofilm formation exemplifies the powerful analyses that are enabled by this computational modeling tool.

  11. Novel multiscale modeling tool applied to Pseudomonas aeruginosa biofilm formation.

    Science.gov (United States)

    Biggs, Matthew B; Papin, Jason A

    2013-01-01

    Multiscale modeling is used to represent biological systems with increasing frequency and success. Multiscale models are often hybrids of different modeling frameworks and programming languages. We present the MATLAB-NetLogo extension (MatNet) as a novel tool for multiscale modeling. We demonstrate the utility of the tool with a multiscale model of Pseudomonas aeruginosa biofilm formation that incorporates both an agent-based model (ABM) and constraint-based metabolic modeling. The hybrid model correctly recapitulates oxygen-limited biofilm metabolic activity and predicts increased growth rate via anaerobic respiration with the addition of nitrate to the growth media. In addition, a genome-wide survey of metabolic mutants and biofilm formation exemplifies the powerful analyses that are enabled by this computational modeling tool.

  12. Flagellation of Pseudomonas aeruginosa in newly divided cells

    Science.gov (United States)

    Zhao, Kun; Lee, Calvin; Anda, Jaime; Wong, Gerard

    2015-03-01

    For monotrichous bacteria, Pseudomonas aeruginosa, after cell division, one daughter cell inherits the old flagellum from its mother cell, and the other grows a new flagellum during or after cell division. It had been shown that the new flagellum grows at the distal pole of the dividing cell when the two daughter cells haven't completely separated. However, for those daughter cells who grow new flagella after division, it still remains unknown at which pole the new flagellum will grow. Here, by combining our newly developed bacteria family tree tracking techniques with genetic manipulation method, we showed that for the daughter cell who did not inherit the old flagellum, a new flagellum has about 90% chances to grow at the newly formed pole. We proposed a model for flagellation of P. aeruginosa.

  13. Pseudomonas aeruginosa Biofilm, a Programmed Bacterial Life for Fitness.

    Science.gov (United States)

    Lee, Keehoon; Yoon, Sang Sun

    2017-06-28

    A biofilm is a community of microbes that typically inhabit on surfaces and are encased in an extracellular matrix. Biofilms display very dissimilar characteristics to their planktonic counterparts. Biofilms are ubiquitous in the environment and influence our lives tremendously in both positive and negative ways. Pseudomonas aeruginosa is a bacterium known to produce robust biofilms. P. aeruginosa biofilms cause severe problems in immunocompromised patients, including those with cystic fibrosis or wound infection. Moreover, the unique biofilm properties further complicate the eradication of the biofilm infection, leading to the development of chronic infections. In this review, we discuss the history of biofilm research and general characteristics of bacterial biofilms. Then, distinct features pertaining to each stage of P. aeruginosa biofilm development are highlighted. Furthermore, infections caused by biofilms on their own or in association with other bacterial species (i.e., multispecies biofilms) are discussed in detail.

  14. Antibacterial Coating for Elimination of Pseudomonas aeruginosa and Escherichia coli

    Directory of Open Access Journals (Sweden)

    Zainal Abidin Ali

    2014-01-01

    Full Text Available A polymer antibacterial surface has been successfully developed. The coating system used silane as binder and Ag particles as antibacterial agent. The silver was synthesized using precipitation method. X-ray diffraction (XRD, field emission scanning electron microscopy (FESEM, Brunauer-Emmett-Teller (BET tests, energy-dispersive X-ray spectroscopy (EDX, and X-ray photoelectron spectroscopy (XPS were carried out to evaluate the silver particles. Antibacterial properties of the coating system were tested against gram-negative bacteria, namely, Pseudomonas aeruginosa and Escherichia coli. Different amounts of Ag were used in the coating to optimize its usage. The Japanese International Standard, JISZ2801, was used for bacteria test and the surface developed complies with the standard being antibacterial.

  15. Pyocyanin degradation by a tautomerizing demethylase inhibits Pseudomonas aeruginosa biofilms.

    Science.gov (United States)

    Costa, Kyle C; Glasser, Nathaniel R; Conway, Stuart J; Newman, Dianne K

    2017-01-13

    The opportunistic pathogen Pseudomonas aeruginosa produces colorful redox-active metabolites called phenazines, which underpin biofilm development, virulence, and clinical outcomes. Although phenazines exist in many forms, the best studied is pyocyanin. Here, we describe pyocyanin demethylase (PodA), a hitherto uncharacterized protein that oxidizes the pyocyanin methyl group to formaldehyde and reduces the pyrazine ring via an unusual tautomerizing demethylation reaction. Treatment with PodA disrupts P. aeruginosa biofilm formation similarly to DNase, suggesting interference with the pyocyanin-dependent release of extracellular DNA into the matrix. PodA-dependent pyocyanin demethylation also restricts established biofilm aggregate populations experiencing anoxic conditions. Together, these results show that modulating extracellular redox-active metabolites can influence the fitness of a biofilm-forming microorganism. Copyright © 2017, American Association for the Advancement of Science.

  16. The implication of Pseudomonas aeruginosa biofilms in infections

    DEFF Research Database (Denmark)

    Rybtke, Morten Theil; Jensen, Peter Ø; Høiby, Niels

    2011-01-01

    . The immune response leading to this chronic inflammation is described. Finally, novel treatment strategies against P. aeruginosa are described including, quorum-sensing inhibition and induced biofilm-dispersion. The tolerance towards currently available antimicrobials calls for development of alternative......Biofilm formation by bacteria is recognized as a major problem in chronic infections due to their recalcitrance against the immune defense and available antibiotic treatment schemes. The opportunistic pathogen Pseudomonas aeruginosa has drawn special attention in this regard due to its severity......-up of the extracellular matrix encasing the biofilm-associated bacteria as well as the elaborate signaling mechanisms employed by the bacterium enables it to withstand the continuous stresses imposed by the immune defense and administered antibiotics resulting in a state of chronic inflammation that damages the host...

  17. Production of biopolymers by Pseudomonas aeruginosa isolated from marine source

    Directory of Open Access Journals (Sweden)

    Nazia Jamil

    2008-06-01

    Full Text Available Two bacterial strains, Pseudomonas aeruginosa CMG607w and CMG1421 produce commercially important biopolymers. CMG607w isolated from the sediments of Lyari outfall to Arabian Sea synthesize the mcl-polyhydroxyalkanoates from various carbon sources. The production of PHAs was directly proportional to the incubation periods. Other strain CMG1421, a dry soil isolate, produced high viscous water absorbing extracellular acidic polysaccharide when it was grown aerobically in the minimal medium containing glucose or fructose or sucrose as sole source of carbon. The biopolymer had the ability to absorb water 400 times more than its dry weight. This property was superior to that of currently used non-degradable synthetic water absorbents. It acted as salt filter and had rheological and stabilizing activity as well.

  18. Hemorrhagic pneumonia in mink caused by Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Salomonsen, Charlotte Mark

    experiencing outbreaks of hemorrhagic pneumonia among their mink was that the disease always started in the mink kits, never in the adults. Furthermore, 39% reported that most deaths occurred in the male mink. The results presented in this thesis suggest that factors of the mink make them more prone to develop......Hemorrhagic pneumonia in mink is an acute and fatal disease caused by Pseudomonas aeruginosa. The mink are typically found dead without prior clinical symptoms. The disease can be highly contagious and varying mortalities on the farm level has been reported. Hemorrhagic pneumonia in mink...... is seasonal with outbreaks almost exclusively occurring from September to November in Denmark. In human medicine, P. aeruginosa is regarded as a pathogen for immune compromised individuals but no underlying disease or immune defect has been identified in mink dying of hemorrhagic pneumonia. In fact, little...

  19. Evolution and Pathoadaptation of Pseudomonas aeruginosa in Cystic Fibrosis Patients

    DEFF Research Database (Denmark)

    Marvig, Rasmus Lykke

    understanding of how bacteria evolve and genetically adapt in a natural environment. In particular we sought to identify the genes that are targeted by mutation to optimize fitness in a given environment, and to understand the evolutionary mechanisms that govern the genetic change. Pseudomonas aeruginosa...... is the dominating pathogen of chronic airway infections in patients with cystic fibrosis (CF), and the bacterial long-term persistence in CF hosts involves mutation and selection of genetic variants with increased fitness in the CF airways. We performed a retrospective study of the P. aeruginosa DK2 clone type......, which is a transmissible clone isolated from chronically infected Danish CF patients over a period of 38 years. Whole-genome analysis of DK2 isolates enabled a finegrained reconstruction of the recent evolutionary history of the DK2 lineage and an identification of bacterial genes targeted by mutations...

  20. Acquisition and Role of Molybdate in Pseudomonas aeruginosa

    Science.gov (United States)

    Pederick, Victoria G.; Eijkelkamp, Bart A.; Ween, Miranda P.; Begg, Stephanie L.; Paton, James C.

    2014-01-01

    In microaerophilic or anaerobic environments, Pseudomonas aeruginosa utilizes nitrate reduction for energy production, a process dependent on the availability of the oxyanionic form of molybdenum, molybdate (MoO42−). Here, we show that molybdate acquisition in P. aeruginosa occurs via a high-affinity ATP-binding cassette permease (ModABC). ModA is a cluster D-III solute binding protein capable of interacting with molybdate or tungstate oxyanions. Deletion of the modA gene reduces cellular molybdate concentrations and results in inhibition of anaerobic growth and nitrate reduction. Further, we show that conditions that permit nitrate reduction also cause inhibition of biofilm formation and an alteration in fatty acid composition of P. aeruginosa. Collectively, these data highlight the importance of molybdate for anaerobic growth of P. aeruginosa and reveal novel consequences of nitrate reduction on biofilm formation and cell membrane composition. PMID:25172858

  1. Hydrocarbon-degradation by Isolate Pseudomonas lundensis UTAR FPE2

    Directory of Open Access Journals (Sweden)

    Adeline, S. Y. Ting

    2009-01-01

    Full Text Available In this study, the potential of isolate Pseudomonas lundensis UTAR FPE2 as a hydrocarbon degrader was established. Their biodegradation activity was first detected with the formation of clearing zones on Bushnell-Hass agar plates, with the largest diameter observed on plates supplemented with paraffin, followed by mineral oil and petrol. Utilization of hydrocarbon sources were again detected in broth cultures supplemented with similar hydrocarbon substrates, where the mean viable cell count recovered from hydrocarbon-supplemented broth cultures were higher than the initial inoculum except for napthalene. In both tests, the isolate showed higher degradability towards aliphatic hydrocarbon sources, and the least activity towards the aromatic hydrocarbon naphthalene. The isolate P. lundensis UTAR FPE2 (8 log10 cfu/mL also degraded crude diesel sample, with 69% degradation during the first three days. To conclude, this study suggests the potential use of this isolate for bioremediation of hydrocarbon-contaminated environments.

  2. Nanohybrids of silver particles on clay platelets delaminate Pseudomonas biofilms.

    Science.gov (United States)

    Tseng, Li-Ping; Juan, Chih-Yin; Lin, Shiun-Long; Doran, Michael R; Lin, Jiang-Jen; Hsu, Shan-Hui; Liao, Jiunn-Wang; Shen, Ching-I; Su, Hong-Lin

    2014-05-01

    To evaluate the effectiveness of novel nanohybrids, composed of silver nanoparticles and nanoscale silicate platelets, to clear Pseudomonas aeruginosa biofilms. The nanohybrids were manufactured from an in situ reduction of silver salts in the silicate platelet dispersion, and then applied to biofilms in vitro and in vivo. In reference to the biocidal effects of gentamycin, the nanohybrids mitigated the spreading of the biofilms, and initiated robust cell death and exfoliation from the superficial layers of the biofilms in vitro. In vivo, the nanohybrids exhibited significant therapeutic effects by eliminating established biofilms from infected corneas and promoting the recovery of corneal integrity. All of the evaluations indicate the high potency of the newly developed silver nanoparticle/nanoscale silicate platelet nanohybrids for eliminating biofilms.

  3. Transcriptome Dynamics of Pseudomonas putida KT2440 under Water Stress

    DEFF Research Database (Denmark)

    Gülez, Gamze; Dechesne, Arnaud; Workman, Christopher

    2012-01-01

    into water forming thin liquid films in the soil pores. Little is known of how bacteria respond to such conditions, where, in addition to facing water deprivation that might impair their metabolism, they have to adapt their dispersal strategy as swimming motility may be compromised. Using the pressurized...... porous surface model (PPSM), which allows creation of thin liquid films by controlling Ψm, we examined the transcriptome dynamics of Pseudomonas putida KT2440. We identified the differentially expressed genes in cells exposed to a mild matric stress (–0.4 MPa) for 4, 24, or 72 h. The major response...... 8000), a nonpermeating solute often used to simulate Ψm, on the gene expression profile and detected a different profile than that observed by directly imposing Ψm. This study is the first transcriptome profiling of KT2440 under directly controlled Ψm and also the first to show the difference in gene...

  4. Nitrite formation from hydroxylamine and oximes by Pseudomonas aeruginosa.

    Science.gov (United States)

    Amarger, N; Alexander, M

    1968-05-01

    Nitrite was formed from hydroxylamine and several oximes by intact cells and extracts of Pseudomonas aeruginosa. The activity was induced by the presence of oximes in the culture medium. Nitroalkanes were not intermediates in the conversion of acetaldoxime, acetone oxime, or butanone oxime to nitrite, since nitromethane inhibited the formation of nitrite from the nitro compounds but not from the corresponding oximes. The oxime apparently functions as a constant source of hydroxylamine during growth of the bacterium. Hydroxylamine at low concentration was converted stoichiometrically to nitrite by extracts of the bacterium; high concentrations were inhibitory. Nicotinamide adenine dinucleotide phosphate, oxygen, and other unidentified cofactors were necessary for the reaction. Actively nitrifying extracts possessed no hydroxylamine-cytochrome c reductase activity. Hyponitrite, nitrous oxide, and nitric oxide were not metabolized.

  5. Outbreak of Pseudomonas aeruginosa bacteraemia in a haematology department

    DEFF Research Database (Denmark)

    Rasmussen, Benjamin Schnack; Christensen, Nikolas; Sørensen, Jan

    2015-01-01

    INTRODUCTION: Infection by Pseudomonas aeruginosa represents a major cause of morbidity and mortality among immunocompromised patients. In Denmark, an increase in P. aeruginosa isolates from blood cultures from a haematology department prompted a hygienic audit in 2007. METHODS: Blood cultures...... the outbreak and 12 months later. The audits were conducted by the method of direct observation. RESULTS: Several PFGE types were involved with no clear association to isolates from environmental samples. The audit revealed poor hygiene related to the handling of central venous catheters. After optimising...... catheter hygiene, the number of P. aeruginosa bacteraemia cases fell significantly. CONCLUSION: Since no clear association between patient and environmental genotype was established, it was suspected that central venous catheters were the main portal of entry. This was further supported by a simultaneous...

  6. Association of Pectolytic Fluorescent PSeudomonas with Postharvest Rots of Onion

    Directory of Open Access Journals (Sweden)

    H.H. El-Hendawy

    2004-12-01

    Full Text Available Five isolates of pectolytic fluorescent pseudomonads were obtained from a rotted onion bulb and identified as Pseudomonas marginalis. At both 4 and 25oC, all isolates caused soft rot to detached plant parts of onion and to carrot, celery, cucumber, pepper, spinach, tomato and turnip (but not garlic. They did not however cause any symptoms in living plants of these same species. These results suggest that the onion isolates are a postharvest pathogen which is not destructive in the field but becomes a threat to fresh vegetables stored at low-temperature. Analysis of cellulosolytic and pectic enzymes revealed that pectic lyases, but not polygalacturonases, pectin methyl esterases and cellulases were produced in culture by each isolate.

  7. Structure, function and regulation of Pseudomonas aeruginosa porins.

    Science.gov (United States)

    Chevalier, Sylvie; Bouffartigues, Emeline; Bodilis, Josselin; Maillot, Olivier; Lesouhaitier, Olivier; Feuilloley, Marc G J; Orange, Nicole; Dufour, Alain; Cornelis, Pierre

    2017-09-01

    Pseudomonas aeruginosa is a Gram-negative bacterium belonging to the γ-proteobacteria. Like other members of the Pseudomonas genus, it is known for its metabolic versatility and its ability to colonize a wide range of ecological niches, such as rhizosphere, water environments and animal hosts, including humans where it can cause severe infections. Another particularity of P. aeruginosa is its high intrinsic resistance to antiseptics and antibiotics, which is partly due to its low outer membrane permeability. In contrast to Enterobacteria, pseudomonads do not possess general diffusion porins in their outer membrane, but rather express specific channel proteins for the uptake of different nutrients. The major outer membrane 'porin', OprF, has been extensively investigated, and displays structural, adhesion and signaling functions while its role in the diffusion of nutrients is still under discussion. Other porins include OprB and OprB2 for the diffusion of glucose, the two small outer membrane proteins OprG and OprH, and the two porins involved in phosphate/pyrophosphate uptake, OprP and OprO. The remaining nineteen porins belong to the so-called OprD (Occ) family, which is further split into two subfamilies termed OccD (8 members) and OccK (11 members). In the past years, a large amount of information concerning the structure, function and regulation of these porins has been published, justifying why an updated review is timely. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Genomic and Genetic Diversity within the Pseudomonas fluorescens Complex.

    Directory of Open Access Journals (Sweden)

    Daniel Garrido-Sanz

    Full Text Available The Pseudomonas fluorescens complex includes Pseudomonas strains that have been taxonomically assigned to more than fifty different species, many of which have been described as plant growth-promoting rhizobacteria (PGPR with potential applications in biocontrol and biofertilization. So far the phylogeny of this complex has been analyzed according to phenotypic traits, 16S rDNA, MLSA and inferred by whole-genome analysis. However, since most of the type strains have not been fully sequenced and new species are frequently described, correlation between taxonomy and phylogenomic analysis is missing. In recent years, the genomes of a large number of strains have been sequenced, showing important genomic heterogeneity and providing information suitable for genomic studies that are important to understand the genomic and genetic diversity shown by strains of this complex. Based on MLSA and several whole-genome sequence-based analyses of 93 sequenced strains, we have divided the P. fluorescens complex into eight phylogenomic groups that agree with previous works based on type strains. Digital DDH (dDDH identified 69 species and 75 subspecies within the 93 genomes. The eight groups corresponded to clustering with a threshold of 31.8% dDDH, in full agreement with our MLSA. The Average Nucleotide Identity (ANI approach showed inconsistencies regarding the assignment to species and to the eight groups. The small core genome of 1,334 CDSs and the large pan-genome of 30,848 CDSs, show the large diversity and genetic heterogeneity of the P. fluorescens complex. However, a low number of strains were enough to explain most of the CDSs diversity at core and strain-specific genomic fractions. Finally, the identification and analysis of group-specific genome and the screening for distinctive characters revealed a phylogenomic distribution of traits among the groups that provided insights into biocontrol and bioremediation applications as well as their role as

  9. The Pseudomonas aeruginosa opportunistic pathogen and human infections.

    Science.gov (United States)

    de Bentzmann, Sophie; Plésiat, Patrick

    2011-07-01

    Pseudomonas aeruginosa, a Gram-negative environmental species and an opportunistic microorganism, establishes itself in vulnerable patients, such as those with cystic fibrosis or hospitalized in intensive care units. It has become a major cause of nosocomial infections worldwide (about 10% of all such infections in most European Union hospitals) and a serious threat to Public Health. The overuse and misuse of antibiotics have also led to the selection of resistant strains against which very few therapeutic options exist. How an environmental species can cause human infections remains a key question that still needs elucidation despite the incredibly high progress that has been made in the P. aeruginosa biology over the past decades. The workshop belonging to Current trends in Biomedicine series, which was held under the sponsorship of the Universidad International de Andalucia between the 8th and the 10th November 2010 brought in the most recent advances in the environmental life of P. aeruginosa, the human P. aeruginosa infections, the new animal models to study Pseudomonas infections, the new genetic aspects including metabolomics, genomics and bioinformatics and the community lifestyle named biofilm that accounts for P. aeruginosa persistence in humans. This workshop organized by Soeren Molin (Danemark), Juan-Luis Ramos (Spain) and Sophie de Bentzmann (France) gathered 46 researchers coming from 11 European and American countries in a small format and was hosted in the 'Sede Antonio Machado' in Baeza. It was organized in seven sessions covering animal models for P. aeruginosa pathogenesis, resistance to drugs, regulatory potency including small RNA, two component systems, extracytoplasmic function sigma factors and trancriptional regulators, new therapies emerging from dissection of molecular mechanisms, and evolutionary mechanisms of P. aeruginosa strains in patients. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  10. CYP2E1PstI/RsaI polymorphism and interaction with tobacco, alcohol and GSTs in gastric cancer susceptibility: A meta-analysis of the literature.

    NARCIS (Netherlands)

    S. Boccia (Stefania); S. de Lauretis (Angelo); F. Gianfagna (Francesco); C.M. van Duijn (Cornelia); G. Ricciardi (Gualtiero)

    2007-01-01

    textabstractStudies investigating the association between cytochrome P450 2E1 (CYP2E1) 5'-flanking region (PstI/RsaI) polymorphism and gastric cancer risk report conflicting results. The rationale for this meta-analysis was to determine whether CYP2E1*2 (c2) variant allele of CYP2E1 increases

  11. WHOP, a Genomic Region Associated With Woody Hosts in the Pseudomonas syringae Complex Contributes to the Virulence and Fitness of Pseudomonas savastanoi pv. savastanoi in Olive Plants.

    Science.gov (United States)

    Caballo-Ponce, Eloy; van Dillewijn, Pieter; Wittich, Regina Michaela; Ramos, Cayo

    2017-02-01

    Bacteria from the Pseudomonas syringae complex belonging to phylogroups 1 and 3 (PG1 and PG3, respectively) isolated from woody hosts share a genomic region herein referred to as WHOP (from woody host and Pseudomonas spp.), which is absent in strains infecting herbaceous organs. In this work, we show that this region is also encoded in P. syringae pv. actinidifoliorum (PG1) and six additional members of PG3, namely, Pseudomonas savastanoi pv. retacarpa, three P. syringae pathovars, Pseudomonas meliae, and Pseudomonas amygdali. Partial conservation of the WHOP occurs in only a few PG2 strains. In P. savastanoi pv. savastanoi NCPPB 3335, the WHOP region is organized into four operons and three independently transcribed genes. While the antABC and catBCA operons mediate the catabolism of anthranilate and catechol, respectively, the ipoABC operon confers oxygenase activity to aromatic compounds. The deletion of antABC, catBCA, or ipoABC in NCPPB 3335 caused reduced virulence in woody olive plants without affecting knot formation in nonwoody plants; catBCA, dhoAB, and PSA3335_3206 (encoding a putative aerotaxis receptor) were also required for the full fitness of this strain exclusively in woody olive plants. Overall, this study sheds light on the evolution and adaptation of bacteria from the P. syringae complex to woody hosts and highlights the enzymatic activities encoded within the WHOP region that are essential for this process.

  12. The molecular mechanism regulating 24-hour rhythm of CYP2E1 expression in the mouse liver

    National Research Council Canada - National Science Library

    Matsunaga, Naoya; Ikeda, Misaki; Takiguchi, Takako; Koyanagi, Satoru; Ohdo, Shigehiro

    2008-01-01

    .... In the present study, we investigated whether hepatic nuclear factor-1alpha (HNF-1alpha) and clock genes with a striking 24-hour rhythm in mouse liver contributed to the 24-hour regulation of CYP2E1 expression...

  13. CYP2E1 epigenetic regulation in chronic, low-level toluene exposure: Relationship with oxidative stress and smoking habit

    Energy Technology Data Exchange (ETDEWEB)

    Jiménez-Garza, Octavio, E-mail: ojimenezgarza@ugto.mx [Health Sciences Division, University of Guanajuato Campus León, Blvd. Puente del Milenio 1001, Fracción del Predio San Carlos, C.P. 37670 León, Guanajuato (Mexico); Baccarelli, Andrea A.; Byun, Hyang-Min [Laboratory of Environmental Epigenetics, Department of Environmental Health, Harvard T.H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA 02115 (United States); Márquez-Gamiño, Sergio [Health Sciences Division, University of Guanajuato Campus León, Blvd. Puente del Milenio 1001, Fracción del Predio San Carlos, C.P. 37670 León, Guanajuato (Mexico); Barrón-Vivanco, Briscia Socorro [Environmental Toxicology and Pollution Laboratory, Nayarit Autonomous University, Av. Ciudad de la Cultura s/n, “Amado Nervo”, Tepic, Nayarit C.P. 63155 (Mexico); Albores, Arnulfo [Department of Toxicology, CINVESTAV, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, 07360 Mexico DF (Mexico)

    2015-08-01

    Background: CYP2E1 is a versatile phase I drug-metabolizing enzyme responsible for the biotransformation of most volatile organic compounds, including toluene. Human toluene exposure increases CYP2E1 mRNA and modifies its activity in leucocytes; however, epigenetic implications of this interaction have not been investigated. Goal: To determine promoter methylation of CYP2E1 and other genes known to be affected by toluene exposure. Methods: We obtained venous blood from 24 tannery workers exposed to toluene (mean levels: 10.86 +/− 7 mg/m{sup 3}) and 24 administrative workers (reference group, mean levels 0.21 +/− 0.02 mg/m{sup 3}) all of them from the city of León, Guanajuato, México. After DNA extraction and bisulfite treatment, we performed PCR-pyrosequencing in order to measure methylation levels at promoter region of 13 genes. Results: In exposed group we found significant correlations between toluene airborne levels and CYP2E1 promoter methylation (r = − .36, p < 0.05), as well as for IL6 promoter methylation levels (r = .44, p < 0.05). Moreover, CYP2E1 promoter methylation levels where higher in toluene-exposed smokers compared to nonsmokers (p = 0.009). We also observed significant correlations for CYP2E1 promoter methylation with GSTP1 and SOD1 promoter methylation levels (r = − .37, p < 0.05 and r = − .34, p < 0.05 respectively). Conclusion: These results highlight the importance of considering CYP2E1 epigenetic modifications, as well as its interactions with other genes, as key factors for unraveling the sub cellular mechanisms of toxicity exerted by oxidative stress, which can initiate disease process in chronic, low-level toluene exposure. People co-exposed to toluene and tobacco smoke are in higher risk due to a possible CYP2E1 repression. - Highlights: • We investigated gene-specific methylation in persons chronically exposed to toluene. • In a previous study, a reduced CYP2E1 activity was observed in these participants. • CYP2E1

  14. High-accuracy local positioning network for the alignment of the Mu2e experiment.

    Energy Technology Data Exchange (ETDEWEB)

    Hejdukova, Jana B. [Czech Technical Univ., Prague (Czech Republic)

    2017-06-01

    This Diploma thesis describes the establishment of a high-precision local positioning network and accelerator alignment for the Mu2e physics experiment. The process of establishing new network consists of few steps: design of the network, pre-analysis, installation works, measurements of the network and making adjustments. Adjustments were performed using two approaches. First is a geodetic approach of taking into account the Earth’s curvature and the metrological approach of a pure 3D Cartesian system on the other side. The comparison of those two approaches is performed and evaluated in the results and compared with expected differences. The effect of the Earth’s curvature was found to be significant for this kind of network and should not be neglected. The measurements were obtained with Absolute Tracker AT401, leveling instrument Leica DNA03 and gyrotheodolite DMT Gyromat 2000. The coordinates of the points of the reference network were determined by the Least Square Meth od and the overall view is attached as Annexes.

  15. Thermal and Structural Analysis of Beamline Components in the Mu2e Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Luke Daniel [Northern Illinois U.

    2016-01-01

    Fermi National Accelerator Laboratory will be conducting the high energy particle physics experiment Muons to Electrons (Mu2e). In this experiment, physicists will attempt to witness and understand an ultra-rare process which is the conversion of a muon into the lighter mass electron, without creating additional neutrinos. The experiment is conducted by first generating a proton beam which will be collided into a target within the production solenoid (PS). This creates a high-intensity muon beam which passes through a transport solenoid (TS) and into the detector solenoid (DS). In the detector solenoid the muons will be stopped in an aluminum target and a series of detectors will measure the electrons produced. These components have been named the DS train since they are coupled and travel on a rail system when being inserted or extracted from the DS. To facilitate the installation and removal of the DS train, a set of external stands and a support stand for the instrumentation feed-through bulkhead (IFB) have been designed. Full analysis of safety factors and performance of these two designs has been completed. The detector solenoid itself will need to be maintained to a temperature of 22°C ± 10°C. This will minimize thermal strain and ensure the accurate position of the components is maintained to the tolerance of 2 mm. To reduce the thermal gradient, a passive heating system has been developed and reported.

  16. Components Qualification for a Possible use in the Mu2e Calorimeter Waveform Digitizer

    Energy Technology Data Exchange (ETDEWEB)

    Di Falco, S. [INFN, Pisa; Donati, S. [INFN, Pisa; Morescalchi, L. [INFN, Pisa; Pedreschi, E. [INFN, Pisa; Pezzullo, G. [INFN, Pisa; Spinella, F. [INFN, Pisa

    2017-03-30

    The Mu2e experiment at Fermilab searches for the charged flavor violating conversion of a muon into an electron in the Coulomb field of a nucleus. The detector consists of a straw tube tracker and a CSI crystal electromagnetic calorimeter, both housed in a superconducting solenoid. Both the front-end and the digital electronics, located inside the cryostat, will be operated in vacuum under a 1 T magnetic field, having to sustain the high flux of neutrons and ionizing particles coming from the muons stopping target. These harsh experimental conditions make the design of the calorimeter waveform digitizer quite challenging. All the selected commercial devices must be tested individually and qualified for radiation hardness and operation in high magnetic field. At the moment the expected particles flux and spectra at the digitizers location are not completely simulated and we are using initial rough estimates to select the components for the first prototype. We are gaining experience in the qualification procedures using the selected components but the choice will be frozen only when dose and neutron flux simulations will be completed. The experimental results of the first qualification campaign are presented.

  17. Derivation of cloud-free-region atmospheric motion vectors from FY-2E thermal infrared imagery

    Science.gov (United States)

    Wang, Zhenhui; Sui, Xinxiu; Zhang, Qing; Yang, Lu; Zhao, Hang; Tang, Min; Zhan, Yizhe; Zhang, Zhiguo

    2017-02-01

    The operational cloud-motion tracking technique fails to retrieve atmospheric motion vectors (AMVs) in areas lacking cloud; and while water vapor shown in water vapor imagery can be used, the heights assigned to the retrieved AMVs are mostly in the upper troposphere. As the noise-equivalent temperature difference (NEdT) performance of FY-2E split window (10.3-11.5 μm, 11.6-12.8 μm) channels has been improved, the weak signals representing the spatial texture of water vapor and aerosols in cloud-free areas can be strengthened with algorithms based on the difference principle, and applied in calculating AMVs in the lower troposphere. This paper is a preliminary summary for this purpose, in which the principles and algorithm schemes for the temporal difference, split window difference and second-order difference (SD) methods are introduced. Results from simulation and cases experiments are reported in order to verify and evaluate the methods, based on comparison among retrievals and the "truth". The results show that all three algorithms, though not perfect in some cases, generally work well. Moreover, the SD method appears to be the best in suppressing the surface temperature influence and clarifying the spatial texture of water vapor and aerosols. The accuracy with respect to NCEP 800 hPa reanalysis data was found to be acceptable, as compared with the accuracy of the cloud motion vectors.

  18. EVALUATION OF THE QUALITY AND SELF PURIFICATION POTENTIAL OF TAJAN RIVER USING QUAL2E MODEL

    Directory of Open Access Journals (Sweden)

    N. Mehrdadi, M. Ghobadi, T. Nasrabadi, H. Hoveidi

    2006-07-01

    Full Text Available Tajan River is among significant rivers of Caspian Sea water basin. Pollution sources that threaten the quality of water in Tajan River may be classified in to two categories namely point and non-point sources. Major pollutants of latter category are Mazandaran wood and pulp, Paksar dairy products and Sari Antibiotic production factories, as well as 600-dastgah residential area. On the other hand, non-point sources whose waste is considered as a distributed load consist of Sari municipal wastewater and agriculture-related pollutants that are drained towards the river. In order to model the quality of river flow, Qual2E model is taken in to consideration. Considering TDS, the river quality is completely acceptable in cold seasons. However, in spring and summer the value of this parameter is increased and this causes some restrictions in the use of this water for irrigation of specific sensitive crops. Agricultural activities and consequent irrigated waters are the major causes of higher reported TDS values in warm seasons. Current status of DO is completely acceptable and this is highly related to the relative high value of width on depth ratio along the river. BOD and COD locate in a fairly poor condition. Quality deterioration is more noticeable in cold seasons. Higher rate of precipitation and consequent greater runoff generation towards the river basin justify the relative increase of mentioned parameters in fall and winter. Generally, non-point pollution sources are more contributed in deterioration of Tajan River water quality.

  19. Forced Two-Phase Helium Cooling Scheme for the Mu2e Transport Solenoid

    Energy Technology Data Exchange (ETDEWEB)

    Tatkowski, G. [Fermilab; Cheban, S. [Fermilab; Dhanaraj, N. [Fermilab; Evbota, D. [Fermilab; Lopes, M. [Fermilab; Nicol, T. [Fermilab; Sanders, R. [Fermilab; Schmitt, R. [Fermilab; Voirin, E. [Fermilab

    2015-01-01

    The Mu2e Transport Solenoid (TS) is an S-shaped magnet formed by two separate but similar magnets, TS-u and TS-d. Each magnet is quarter-toroid shaped with a centerline radius of approximately 3 m utilizing a helium cooling loop consisting of 25 to 27 horizontal-axis rings connected in series. This cooling loop configuration has been deemed adequate for cooling via forced single phase liquid helium; however it presents major challenges to forced two-phase flow such as “garden hose” pressure drop, concerns of flow separation from tube walls, difficulty of calculation, etc. Even with these disadvantages, forced two-phase flow has certain inherent advantages which make it a more attractive option than forced single phase flow. It is for this reason that the use of forced two-phase flow was studied for the TS magnets. This paper will describe the analysis using helium-specific pressure drop correlations, conservative engineering approach, helium properties calculated and updated at over fifty points, and how the results compared with those in literature. Based on the findings, the use of forced-two phase helium is determined to be feasible for steady-state cooling of the TS solenoids

  20. CYP2E1 epigenetic regulation in chronic, low-level toluene exposure: Relationship with oxidative stress and smoking habit.

    Science.gov (United States)

    Jiménez-Garza, Octavio; Baccarelli, Andrea A; Byun, Hyang-Min; Márquez-Gamiño, Sergio; Barrón-Vivanco, Briscia Socorro; Albores, Arnulfo

    2015-08-01

    CYP2E1 is a versatile phase I drug-metabolizing enzyme responsible for the biotransformation of most volatile organic compounds, including toluene. Human toluene exposure increases CYP2E1 mRNA and modifies its activity in leucocytes; however, epigenetic implications of this interaction have not been investigated. To determine promoter methylation of CYP2E1 and other genes known to be affected by toluene exposure. We obtained venous blood from 24 tannery workers exposed to toluene (mean levels: 10.86+/-7mg/m(3)) and 24 administrative workers (reference group, mean levels 0.21+/-0.02mg/m(3)) all of them from the city of León, Guanajuato, México. After DNA extraction and bisulfite treatment, we performed PCR-pyrosequencing in order to measure methylation levels at promoter region of 13 genes. In exposed group we found significant correlations between toluene airborne levels and CYP2E1 promoter methylation (r=-.36, ptoluene-exposed smokers compared to nonsmokers (p=0.009). We also observed significant correlations for CYP2E1 promoter methylation with GSTP1 and SOD1 promoter methylation levels (r=-.37, ptoluene exposure. People co-exposed to toluene and tobacco smoke are in higher risk due to a possible CYP2E1 repression. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. MECANISMOS DE RESISTENCIA EN PSEUDOMONAS AERUGINOSA: ENTENDIENDO A UN PELIGROSO ENEMIGO Resistance mechanisms in Pseudomonas aeruginosa: understanding a dangerous enemy

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Gómez Álvarez

    2005-01-01

    Full Text Available Pseudomonas aeruginosa es un bacilo Gram negativo no fermentador, ampliamente relacionado con la infección nosocomial. Este tipo de infecciones se presentan en pacientes severamente comprometidos, hospitalizados especialmente en unidades de cuidado intensivo, donde existe una alta presión de selección de resistencia por parte de los antibióticos. Estas infecciones nosocomiales tienen implicaciones en el pronóstico del paciente, los costos del tratamiento, la estancia hospitalaria, la morbilidad y la mortalidad. Es importante que en cada institución hospitalaria se mantenga una estrecha vigilancia de los perfiles de resistencia de esta bacteria, con el fin de reconocer sus mecanismos de resistencia, su evolución y la forma de transferencia. En este sentido, un concepto como "la lectura interpretativa del antibiograma" se impone y ayuda al clínico a inferir los posibles mecanismos de resistencia que exhibe la bacteria para de esta manera orientar el uso de la terapia antibiótica y avanzar en el gran desafío que implica enfrentar las consecuencias de la infección por P. aeruginosa.Pseudomonas aeruginosa is a Gram-negative fermentative bacilli related with nosocomial infections. This kind of infections is more frequent in critical ill patients, specially in intensive care units, where a high pressure selection is ejerxed. Nosocomial infections are associated with poor prognosis, increased treatment cost, cubed length, morbidity and mortality. Each health care institution might establish antimicrobial resistance surveillance in order to recognize antimicrobial resistance mechanisms, and transference of resistance of this pathogen. In the other hand, concepts as "interpretative reading" help the clinician to infer the possible mechanisms involved and in this way guide the antimicrobial therapy in order to boarding the challenge of this kind of infections.

  2. Molecular detection of an atypical, highly resistant, clonal Pseudomonas aeruginosa isolate in cystic fibrosis patients.

    LENUS (Irish Health Repository)

    Keating, Deirdre

    2013-03-01

    The identification of Pseudomonas aeruginosa (P. aeruginosa) isolates in sputum from cystic fibrosis (CF) patients can be challenging due to the multitude of phenotypic changes isolates undergo during adaptation to the microenvironment of the CF lung.

  3. Colistin-Tobramycin Combinations Are Superior to Monotherapy Concerning the Killing of Biofilm Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Herrmann, G.; Yang, Liang; Wu, H.

    2010-01-01

    Background. Antibiotic combination therapy might be more efficient than single antibiotics to combat Pseudomonas aeruginosa biofilms in the airways of patients with cystic fibrosis. We tested the ability of colistin sulphatetobramycin combinations and single antibiotics to kill P. aeruginosa biof...

  4. The cellodextrinase from Pseudomonas fluorescens subsp. cellulosa consists of multiple functional domains

    National Research Council Canada - National Science Library

    Ferreira, L M; Hazlewood, G P; Barker, P J; Gilbert, H J

    1991-01-01

    A genomic library of Pseudomonas fluorescens subsp. cellulosa DNA was constructed in pUC18 and Escherichia coli recombinants expressing 4-methylumbelliferyl beta-D-cellobioside-hydrolysing activity (MUCase) were isolated...

  5. The Effect of Strict Segregation on Pseudomonas aeruginosa in Cystic Fibrosis Patients

    NARCIS (Netherlands)

    van Mansfeld, Rosa; de Vrankrijker, Angelica; Brimicombe, Roland; Heijerman, Harry; Teding van Berkhout, Ferdinand; Spitoni, Cristian|info:eu-repo/dai/nl/304625957; Grave, Sanne; van der Ent, Cornelis; Wolfs, Tom; Willems, Rob; Bonten, Marc

    2016-01-01

    INTRODUCTION: Segregation of patients with cystic fibrosis (CF) was implemented to prevent chronic infection with epidemic Pseudomonas aeruginosa strains with presumed detrimental clinical effects, but its effectiveness has not been carefully evaluated. METHODS: The effect of strict segregation on

  6. Pseudomonas aeruginosa biofilm infections in cystic fibrosis: insights into pathogenic processes and treatment strategies

    DEFF Research Database (Denmark)

    Hassett, Daniel J; Korfhagen, Thomas R; Irvin, Randall T

    2010-01-01

    CF airway mucus can be infected by opportunistic microorganisms, notably Pseudomonas aeruginosa. Once organisms are established as biofilms, even the most potent antibiotics have little effect on their viability, especially during late-stage chronic infections. Better understanding...

  7. Antibiotic therapy against Pseudomonas aeruginosa in cystic fibrosis : a European consensus

    NARCIS (Netherlands)

    Döring, G; Conway, S P; Heijerman, H G; Hodson, M E; Høiby, N; Smyth, A; Touw, D J

    2000-01-01

    Cystic fibrosis (CF) is the most common lethal hereditary disorder with autosomal recessive heredity in caucasians. The majority of CF patients suffer from chronic respiratory infection with the opportunistic bacterial pathogen Pseudomonas aeruginosa. No consensus among clinicians has been reached

  8. Flavonoids from Rhizophora conjugata fruit extract blocks virulence factors of Pseudomonas aeruginosa

    Digital Repository Service at National Institute of Oceanography (India)

    Naik, D.; Tilvi, S.; DeSouza, L.

    Pseudomonas aeruginosa is a major nosocomial pathogen which causes hospital acquired infections and recently has gained importance as a model to study antibiotic resistance. In the present study, we investigated the effect of methanol and methanol...

  9. Quorum sensing is necessary for the virulence of Pseudomonas aeruginosa during urinary tract infection

    National Research Council Canada - National Science Library

    Kumar, Ravi; Chhibber, Sanjay; Harjai, Kusum

    2009-01-01

    .... To understand the role of quorum sensing in pathogenesis of urinary tract infections, wild type Pseudomonas aeruginosa, having both functional las and rhl quorum sensing systems, and its isogenic...

  10. Quorum Sensing and Virulence of Pseudomonas aeruginosa during Lung Infection of Cystic Fibrosis Patients

    DEFF Research Database (Denmark)

    Bjarnsholt, T.; Jensen, P.O.; Jakobsen, T.H.

    2010-01-01

    Pseudomonas aeruginosa is the predominant microorganism in chronic lung infection of cystic fibrosis patients. The chronic lung infection is preceded by intermittent colonization. When the chronic infection becomes established, it is well accepted that the isolated strains differ phenotypically...

  11. Dynamics of mutations during development of resistance by Pseudomonas aeruginosa against five antibiotics

    NARCIS (Netherlands)

    Feng, Y.; Jonker, M.J.; Moustakas, I.; Brul, S.; ter Kuile, B.H.

    2016-01-01

    Pseudomonas aeruginosa is an opportunistic pathogen that causes considerable morbidity and mortality, specifically in the intensive care. Antibiotic resistant variants of this organism are more difficult to treat and cause substantial extra costs compared to susceptible strains. In the laboratory,

  12. Quinolone Signaling in the Cell-to-Cell Communication System of Pseudomonas aeruginosa

    National Research Council Canada - National Science Library

    Everett C. Pesci; Jared B. J. Milbank; James P. Pearson; Susan McKnight; Andrew S. Kende; E. Peter Greenberg; Barbara H. Iglewski

    1999-01-01

    ...) that consists of a homoserine lactone with a fatty acid side chain. Such is the case in the opportunistic human pathogen Pseudomonas aeruginosa, which contains two quorum sensing systems (las and rhl...

  13. Evolution of the Pseudomonas aeruginosa mutational resistome in an international Cystic Fibrosis clone

    DEFF Research Database (Denmark)

    López-Causapé, Carla; Madsen Sommer, Lea Mette; Cabot, Gabriel

    2017-01-01

    Emergence of epidemic clones and antibiotic resistance development compromises the management of Pseudomonas aeruginosa cystic fibrosis (CF) chronic respiratory infections. Whole genome sequencing (WGS) was used to decipher the phylogeny, interpatient dissemination, WGS mutator genotypes (mutome)...

  14. Electricity generation and wastewater treatment of oil refinery in microbial fuel cells using Pseudomonas putida

    National Research Council Canada - National Science Library

    Majumder, Dip; Maity, Jyoti Prakash; Tseng, Min-Jen; Nimje, Vanita Roshan; Chen, Hau-Ren; Chen, Chien-Cheng; Chang, Young-Fo; Yang, Tsui-Chu; Chen, Chen-Yen

    2014-01-01

    .... Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days...

  15. Epidemiology and Ecology of Opportunistic Premise Plumbing Pathogens: Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa

    Science.gov (United States)

    BACKGROUND: Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa are opportunistic premise plumbing pathogens (OPPPs) that persist and grow in household plumbing, habitats they share with humans. Infections caused by these OPPPs involve individuals with preexis...

  16. TSCA Experimental Release Application Approved for Pseudomonas putida Strains (fact sheet)

    Science.gov (United States)

    In 1998, EPA approved the TERAs R98-0004/5 submitted by the National Explosives Waste Technology & Evaluation Center (NEWTEC) and the Oak Ridge National Laboratory for field trials of two modified strains of Pseudomonas putida (P.putida).

  17. Indexing the Pseudomonas specialized metabolome enabled the discovery of poaeamide B and the bananamides

    NARCIS (Netherlands)

    Nguyen, D.; Melnik, Alexey V; Koyama, N.; Lu, X.; Schorn, M.; Fang, J.; Aguinaldo, K.; Lincecum Jr., T.; Ghequire, M.; Carrion, V.J.; Cheng, T.; Malone, J.; Mauchline, T.; Sanchez, L.; Marm Kilpatrick, A.; Raaijmakers, J.M.; De Mot, Rene; Moore, B.; Medema, Marnix H; Dorrestein, Pieter C.

    2016-01-01

    Pseudomonads are cosmopolitan microorganisms able to produce a wide array of specialized metabolites. These molecules allow Pseudomonas to scavenge nutrients, sense population density and enhance or inhibit growth of competing microorganisms. However, these valuable metabolites are typically

  18. Indexing the Pseudomonas specialized metabolome enabled the discovery of poaeamide B and the bananamides

    NARCIS (Netherlands)

    Nguyen, Don D.; Melnik, Alexey V.; Koyama, Nobuhiro; Lu, Xiaowen; Schorn, Michelle; Fang, Jinshu; Aguinaldo, Kristen; Lincecum, Tommie L.; Ghequire, Maarten G.K.; Carrion, Victor J.; Cheng, Tina L.; Duggan, Brendan M.; Malone, Jacob G.; Mauchline, Tim H.; Sanchez, Laura M.; Marm Kilpatrick, A.; Raaijmakers, Jos M.; Mot, De René; Moore, Bradley S.; Medema, Marnix H.; Dorrestein, Pieter C.

    2016-01-01

    Pseudomonads are cosmopolitan microorganisms able to produce a wide array of specialized metabolites. These molecules allow Pseudomonas to scavenge nutrients, sense population density and enhance or inhibit growth of competing microorganisms. However, these valuable metabolites are typically

  19. Promotion of plant growth by Pseudomonas fluorescens strain SS101 via novel volatile organic compounds

    NARCIS (Netherlands)

    Park, Yong-Soon; Dutta, Swarnalee; Ann, Mina; Raaijmakers, Jos M.; Park, Kyungseok

    2015-01-01

    Abstract Volatile organic compounds (VOCs) from plant growth-promoting rhizobacteria (PGPR) play key roles in modulating plant growth and induced systemic resistance (ISR) to pathogens. Despite their significance, the physiological functions of the specific VOCs produced by Pseudomonas fluorescens

  20. Antimicrobial Resistance and Molecular Typing of Pseudomonas Aeruginosa Isolated from Surgical Wounds in Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    Kehinde Akinsinde

    2012-06-01

    Full Text Available The aim of the study was to determine the resistance patterns of Pseudomonas aeruginosa isolates recovered from patients with surgical wounds in hospitals and also to investigate their epidemiological relatedness using molecular typing techniques. Twenty Pseudomonas sp. isolated from surgical wounds were subjected to antibiotic susceptibility testing by disk diffusion, plasmid profile, SDS-PAGE and PCR using the parC, gyr A gene and RAPD using the 1254 primer. The isolates showed resistance to 12 different antibiotics with six being 100% resistant. Plasmids were detected in 16 (80% of the isolates. The RAPD-PCR using the primer 1254, SDS-PAGE classified the 20 Pseudomonas spp. into 5 and 6 types respectively. Pseudomona aeruginosa strains isolated from surgical wounds were generally resistant to a broad range of antibiotics and this is rather worrisome. The typing techniques classified the 20 isolates into 5 and 6 groups.

  1. Antimicrobial resistance and molecular typing of pseudomonas aeruginosa isolated from surgical wounds in Lagos, Nigeria.

    Science.gov (United States)

    Smith, Stella; Ganiyu, Olaniyi; John, Rachael; Fowora, Muinah; Akinsinde, Kehinde; Odeigah, Peter

    2012-01-01

    The aim of the study was to determine the resistance patterns of Pseudomonas aeruginosa isolates recovered from patients with surgical wounds in hospitals and also to investigate their epidemiological relatedness using molecular typing techniques. Twenty Pseudomonas sp. isolated from surgical wounds were subjected to antibiotic susceptibility testing by disk diffusion, plasmid profile, SDS-PAGE and PCR using the parC, gyr A gene and RAPD using the 1254 primer. The isolates showed resistance to 12 different antibiotics with six being 100% resistant. Plasmids were detected in 16 (80%) of the isolates. The RAPD-PCR using the primer 1254, SDS-PAGE classified the 20 Pseudomonas spp. into 5 and 6 types respectively. Pseudomona aeruginosa strains isolated from surgical wounds were generally resistant to a broad range of antibiotics and this is rather worrisome. The typing techniques classified the 20 isolates into 5 and 6 groups.

  2. Contribution of cell elongation to the biofilm formation of Pseudomonas aeruginosa during anaerobic respiration

    National Research Council Canada - National Science Library

    Yoon, Mi Young; Lee, Kang-Mu; Park, Yongjin; Yoon, Sang Sun

    2011-01-01

    Pseudomonas aeruginosa, a gram-negative bacterium of clinical importance, forms more robust biofilm during anaerobic respiration, a mode of growth presumed to occur in abnormally thickened mucus layer...

  3. Allantoinase from Pseudomonas Aeruginosa. Purification, Properties and Immunochemical Characterization of Its In Vivo Inactivation

    NARCIS (Netherlands)

    Janssen, Dick B.; Smits, Rob A.M.M.; Drift, Chris van der

    1982-01-01

    The catabolic enzyme allantoinase is rapidly inactivated in cells of Pseudomonas aeruginosa when the stationary phase of growth is reached. This process is irreversible since the protein synthesis inhibitor chloramphenicol completely blocked the reappearance of allantoinase activity that is observed

  4. Inhibition of human monocyte chemotaxis and chemiluminescence by Pseudomonas aeruginosa elastase

    DEFF Research Database (Denmark)

    Kharazmi, A; Nielsen, H

    1991-01-01

    The in vitro effect of Pseudomonas aeruginosa elastase on human monocyte function was examined. Mononuclear cells isolated from the peripheral blood of healthy individuals were incubated with various concentrations of elastase, and the chemotactic activity and chemiluminescence response of these ...

  5. Identification of pesticide-degrading Pseudomonas strains as poly-β ...

    African Journals Online (AJOL)

    . 14 strains of pesticide-degrading Pseudomonas isolated from subtropical lowland soil in southern Brazil were analyzed using optical microscopy. Lipid inclusions were identified in four strains, and three of them, which degraded the pesticide ...

  6. Characterization of fluorescent pseudomonas spp. associated with roots and soil of two sorghum genotypes

    Science.gov (United States)

    Sorghum, useful for bioenergy feedstock, animal feed, and food, requires economical methods for disease prevention and control. Fluorescent Pseudomonas spp. were isolated from sorghum roots and adherent soil to identify isolates that inhibited sorghum fungal pathogens. Pseudomonads were collected fr...

  7. Activation of pulmonary and lymph node dendritic cells during chronic Pseudomonas aeruginosa lung infection in mice

    DEFF Research Database (Denmark)

    Damlund, Dina S. M.; Christophersen, Lars; Jensen, Peter Østrup

    2016-01-01

    The majority of cystic fibrosis (CF) patients acquire chronic Pseudomonas aeruginosa lung infection, resulting in increased mortality and morbidity. The chronic P. aeruginosa lung infection is characterized by bacteria growing in biofilm surrounded by polymorphonuclear neutrophils (PMNs). However...

  8. Initial Pseudomonas aeruginosa infection in patients with cystic fibrosis: characteristics of eradicated and persistent isolates

    DEFF Research Database (Denmark)

    Tramper-Stranders, G. A.; van der Ent, C. K.; Molin, Søren

    2012-01-01

    Clin Microbiol Infect 2012; 18: 567574 Abstract Despite intensive eradication therapy, some CF patients with early Pseudomonas aeruginosa infection rapidly develop a chronic infection. To elucidate factors associated with this persistence, bacterial characteristics of early P. aeruginosa isolates...

  9. Functional, genetic and chemical characterization of biosurfactants produced by plant growth-promoting Pseudomonas putida 267

    NARCIS (Netherlands)

    Kruijt, M.; Tran, H.; Raaijmakers, J.M.

    2009-01-01

    Aims: Plant growth-promoting Pseudomonas putida strain 267, originally isolated from the rhizosphere of black pepper, produces biosurfactants that cause lysis of zoospores of the oomycete pathogen Phytophthora capsici. The biosurfactants were characterized, the biosynthesis gene(s) partially

  10. Potencial de pseudomonas spp. fluorescentes para biocontrole de alternaria ricini em mamoneira Potential of fluorescent pseudomonas spp. For biological control of alternaria ricini on castorbean

    Directory of Open Access Journals (Sweden)

    Francisco de A.G. da Silva

    1998-06-01

    Full Text Available The potential of fluorescent Pseudomonas spp. to control Alternaria leaf spot on castorbean, caused by Alternaria ricini, was studied under greenhouse conditions. Two periods for antagonist applications were tested: 48h before and simultaneously to the pathogen inoculation. Among the antagonists tested JA4 and BJ22 were the most effectives showing disease severity reduction of 20.9% and 17.8% respectively, when applied simultaneously. The effect of Pseudomonas spp. on the micelial growth and sporulation was also studied throughout three different methods (funel, streak and celophane. Inhibition of micelial growth and sporulation was observed. There was no correlation between in vitro and in vivo data. Antibiosis was showed as a mode of action for Pseudomonas spp. in relation to Alternaria ricini. Ultrastructural studies confirmed the inhibition of spore germination by the bacteria.

  11. Biofilm Formation Mechanisms of Pseudomonas aeruginosa Predicted via Genome-Scale Kinetic Models of Bacterial Metabolism

    Science.gov (United States)

    2016-03-15

    RESEARCH ARTICLE Biofilm Formation Mechanisms of Pseudomonas aeruginosa Predicted via Genome-Scale Kinetic Models of Bacterial Metabolism Francisco G...jaques.reifman.civ@mail.mil Abstract A hallmark of Pseudomonas aeruginosa is its ability to establish biofilm -based infections that are difficult to...eradicate. Biofilms are less susceptible to host inflammatory and immune responses and have higher antibiotic tolerance than free-living planktonic

  12. Antibiotic resistance patterns of Pseudomonas spp. isolated from the River Danube

    Directory of Open Access Journals (Sweden)

    Clemens eKittinger

    2016-05-01

    Full Text Available Spread and persistence of antibiotic resistance pose a severe threat to human health, yet there is still lack of knowledge about reservoirs of antibiotic resistant bacteria in the environment. We took the opportunity of the Joint Danube Survey 3 (JDS3, the world's biggest river research expedition of its kind in 2013, to analyse samples originating from different sampling points along the whole length of the river. Due to its high clinical relevance, we concentrated on the characterization of Pseudomonas spp. and evaluated the resistance profiles of Pseudomonas spp. which were isolated from eight sampling points. In total, 520 Pseudomonas isolates were found, 344 (66.0% isolates were identified as Pseudomonas putida, and 141 (27.1% as Pseudomonas fluorescens, all other Pseudomonas species were represented by less than five isolates, among those two P. aeruginosa isolates. Thirty seven percent (37% of all isolated Pseudomonas species showed resistance to at least one out of eleven tested antibiotics. The most common resistance was against meropenem (30.4% / 158 isolates piperacillin/tazobactam (10.6% / 55 isolates and ceftazidime (4.2% / 22 isolates. 16 isolates (3.1% / 16 isolates were multi-resistant. For each tested antibiotic at least one resistant isolate could be detected. Sampling points from the upper stretch of the River Danube showed more resistant isolates than downriver. Our results suggest that antibiotic resistance can be acquired by and persists even in Pseudomonas species that are normally not in direct contact with humans. A possible scenario is that these bacteria provide a reservoir of antibiotic resistance genes that can spread to related human pathogens by horizontal gene transfer.

  13. Post-transcriptional regulation of gene PA5507 controls PQS concentration in Pseudomonas aeruginosa

    OpenAIRE

    Tipton, Kyle A.; Coleman, James P.; Pesci, Everett C.

    2015-01-01

    Pseudomonas aeruginosa can sense and respond to a myriad of environmental signals and utilizes a system of small molecules to communicate through intercellular signaling. The small molecule 2-heptyl-3-hydroxy-4-quinolone (Pseudomonas Quinolone Signal [PQS]) is one of these signals and its synthesis is important for virulence. Previously, we identified an RpiR-type transcriptional regulator, QapR, that positively affects PQS production by repressing the qapR operon. An in-frame deletion of thi...

  14. ANOMALOUS BLUE COLOURING OF MOZZARELLA CHEESE INTENTIONALLY CONTAMINATED WITH PIGMENT PRODUCING STRAINS OF PSEUDOMONAS FLUORESCENS

    Directory of Open Access Journals (Sweden)

    P. Sechi

    2011-04-01

    Full Text Available In summer 2010 a large outbreak of anomalous blue coloration of mozzarella cheese was recorded in Italy and some northern European countries. Official laboratory analysis and health authorities linked the outbreak to the contamination of processing water with strains of Pseudomonas fluorescens, although several expert raised the question of how to unequivocally link the blue coloring to the presence of the micro-organism. In an attempt to set-up a method to determine whether a given Pseudomonas spp. strain is responsible of the defect, an in vitro system for the evaluation of blue colouring of mozzarella cheese intentionally contaminated with strains of Pseudomonas fluorescens. was developed The system is aimed to ascertain whether P. fluorescens strains, isolated from mozzarella cheese with anomalous blue coloration, are able to reproduce the blue coloration under controlled experimental condition. 96 trials of experimental inoculation of mozzarella cheese in different preservation liquids, were conducted using various suspension of Pseudomonas spp. (P. fluorescens ATCC 13525, P. fluorescens CFBP 3150, one P. fluorescens field strain isolated from blue-colored mozzarella cheese and P. aeruginosa ATCC 10145 as positive control at different concentrations and incubated at different temperatures. Growth curve of all Pseudomonas spp. strains tested demonstrated that after three days of incubation the concentration was generally higher than 106 CFU/g of mozzarella cheese incubated in Tryptic Soy Broth (TSB, and higher than 105 CFU/g of mozzarella cheese incubated in preservation liquid. All mozzarella cheeses inoculated with the field strain of Pseudomonas fluorescens showed the characteristic anomalous blue coloration, which is often associated with Pseudomonas fluorescens contamination of water used during mozzarella cheesemaking. With the proposed system, which enabled a considerable amount of samples to be analysed under controlled experimental

  15. Identification of small molecule inhibitors of Pseudomonas aeruginosa exoenzyme S using a yeast phenotypic screen.

    OpenAIRE

    Anthony Arnoldo; Jasna Curak; Saranya Kittanakom; Igor Chevelev; Vincent T Lee; Mehdi Sahebol-Amri; Becky Koscik; Lana Ljuma; Peter J Roy; Antonio Bedalov; Guri Giaever; Corey Nislow; A Rod Merrill; Stephen Lory; Igor Stagljar

    2008-01-01

    Pseudomonas aeruginosa is an opportunistic human pathogen that is a key factor in the mortality of cystic fibrosis patients, and infection represents an increased threat for human health worldwide. Because resistance of Pseudomonas aeruginosa to antibiotics is increasing, new inhibitors of pharmacologically validated targets of this bacterium are needed. Here we demonstrate that a cell-based yeast phenotypic assay, combined with a large-scale inhibitor screen, identified small molecule inhibi...

  16. Antimicrobial Susceptibility Pattern of Pseudomonas aeruginosa Isolated from Patients Referring to Hospitals

    OpenAIRE

    Zeynab Golshani; Ali Mohammad Ahadi; Ali Sharifzadeh

    2012-01-01

    Please cite this article as: Golshani Z, Ahadi AM, Sharifzadeh A. Antimicrobial Susceptibility Pattern of Pseudomonas aeruginosa Isolated from Patients Referring to Hospitals. Arch Hyg Sci 2012;1(2):48-53. Abstract: Background & Aims of the Study: The aim of this study was to detect and survey the antibiotic resistance pattern of Pseudomonas (P.) aeruginosa isolated from patients in Isfahan (located in central Iran) hospitals. Materials & Methods : A Total of 50 clinical isola...

  17. Mechanism-based inactivation of cytochromes P450 2E1 and 2E1 T303A by tert-butyl acetylenes: characterization of reactive intermediate adducts to the heme and apoprotein.

    Science.gov (United States)

    Blobaum, Anna L; Kent, Ute M; Alworth, William L; Hollenberg, Paul F

    2002-12-01

    The kinetics for the inactivation of cytochrome P450 2E1 and the mutant P450 2E1 T303A by tert-butyl acetylene (tBA) and tert-butyl 1-methyl-2-propynyl ether (tBMP) were investigated. The two acetylenes inactivated the 7-ethoxy-4-(trifluoromethyl)coumarin (7-EFC) O-deethylation activity of purified rabbit P450s 2E1 and 2E1 T303A in a reconstituted system in a time-, concentration-, and NADPH-dependent manner. The K(I) values for the inactivation of P450s 2E1 and 2E1 T303A by tBA were 1.0 and 2.0 mM, the k(inact) values were 0.20 and 0.38 min(-)(1), and the t(1/2) values were 3.5 and 1.8 min, respectively. The K(I) values for the tBMP-inactivated P450s were 0.1 and 1.0 mM, the k(inact) values were 0.12 and 0.07 min(-)(1), and the t(1/)(2) values were 5.9 and 10.2 min, respectively. Losses in enzyme activity occurred with concurrent losses in the P450 CO spectrum and P450 heme, which were accompanied by the appearance of two different tBA- or tBMP-modified heme products in each inactivated sample. LC-MS analysis of the adducts showed masses of 661 or 705 Da, consistent with the mass of an iron-depleted heme plus the masses of a tBA or tBMP reactive intermediate and one oxygen atom, respectively. Only the tBA-inactivated P450 2E1 revealed a tBA-adducted apoprotein with an increase in mass of 99 Da, corresponding to the mass of tBA plus one oxygen atom. Surprisingly, the inactivation, CO spectral and heme loss, and heme adduct formation of the tBA-inactivated T303A mutant were completely reversible after dialysis. In addition, metabolism of para-nitrophenol was not compromised by the tBA-inactivated T303A mutant. Therefore, our studies on the inactivation of P450s 2E1 and 2E1 T303A by tBA and tBMP suggest the existence of three distinct mechanisms for inactivation, among which includes a novel, reversible heme alkylation that has not been previously described with P450 enzymes.

  18. The US DOE A2e Mesoscale to Microscale Coupling Project: Nonstationary Modeling Techniques and Assessment

    Science.gov (United States)

    Haupt, Sue Ellen; Kosovic, Branko; Shaw, William

    2017-04-01

    The purpose of the US DOE's Mesoscale-Microscale Coupling (MMC) Project is to develop, verify, and validate physical models and modeling techniques that bridge the most important atmospheric scales that determine wind plant performance and reliability. As part of DOE's Atmosphere to Electrons (A2e) program, the MMC project seeks to create a new predictive numerical simulation capability that is able to represent the full range of atmospheric flow conditions impacting wind plant performance. The recent focus of MMC has been on nonstationary conditions over flat terrain. These nonstationary cases are critical for wind energy and represent a primary need for mesoscale meteorological forcing of the microscale models. The MMC team modeled two types of non-stationary cases: 1) diurnal cycles in which the daytime convective boundary layer collapses with the setting of the sun when the surface heat flux changes from positive to negative, passing through a brief period of neutral stability before becoming stable, with smaller scale turbulence and the potential for low level jet (LLJ) formation; and 2) frontal passage as an example of a synoptic weather event that may cause relatively rapid changes in wind speed and direction. The team compared and contrasted two primary techniques for non-stationary forcing of the microscale by the mesoscale model. The first is to use the tendencies from the mesoscale model to directly force the microscale mode. The second method is to couple not only the microscale domain's internal forcing parameters, but also its lateral boundaries, to a mesoscale simulation. While the boundary coupled approach provides the greatest generality, since the mesoscale flow information providing the lateral boundary information for the microscale domain contains no explicit turbulence information, the approach requires methods to accelerate turbulence production at the microscale domain's inflow boundaries. Forefront assessment strategies, including comparing

  19. Inhibiting Skp2 E3 Ligase Suppresses Bleomycin-Induced Pulmonary Fibrosis

    Directory of Open Access Journals (Sweden)

    Masashi Mikamo

    2018-02-01

    Full Text Available Idiopathic pulmonary fibrosis (IPF is a progressive disease with poor prognosis and no curative therapies. SCF-Skp2 E3 ligase is a target for cancer therapy, but there have been no reports about Skp2 as a target for IPF. Here we demonstrate that Skp2 is a promising therapeutic target for IPF. We examined whether disrupting Skp2 suppressed pulmonary fibrosis in a bleomycin (BLM-induced mouse model and found that pulmonary fibrosis was significantly suppressed in Skp2-deficient mice compared with controls. The pulmonary accumulation of fibrotic markers such as collagen type 1 and fibronectin in BLM-infused mice was decreased in Skp2-deficient mice. Moreover, the number of bronchoalveolar lavage fluid cells accompanied with pulmonary fibrosis was significantly diminished. Levels of the Skp2 target p27 were significantly decreased by BLM-administration in wild-type mice, but recovered in Skp2−/− mice. In vimentin-positive mesenchymal fibroblasts, the decrease of p27-positive cells and increase of Ki67-positive cells by BLM-administration was suppressed by Skp2-deficency. As these results suggested that inhibiting Skp2 might be effective for BLM-induced pulmonary fibrosis, we next performed a treatment experiment using the Skp2 inhibitor SZL-P1-41. As expected, BLM-induced pulmonary fibrosis was significantly inhibited by SZL-P1-41. Moreover, p27 levels were increased by the SZL-P1-41 treatment, suggesting p27 may be an important Skp2 target for BLM-induced pulmonary fibrosis. Our study suggests that Skp2 is a potential molecular target for human pulmonary fibrosis including IPF.

  20. The human orphan nuclear receptor tailless (TLX, NR2E1 is druggable.

    Directory of Open Access Journals (Sweden)

    Cindy Benod

    Full Text Available Nuclear receptors (NRs are an important group of ligand-dependent transcriptional factors. Presently, no natural or synthetic ligand has been identified for a large group of orphan NRs. Small molecules to target these orphan NRs will provide unique resources for uncovering regulatory systems that impact human health and to modulate these pathways with drugs. The orphan NR tailless (TLX, NR2E1, a transcriptional repressor, is a major player in neurogenesis and Neural Stem Cell (NSC derived brain tumors. No chemical probes that modulate TLX activity are available, and it is not clear whether TLX is druggable. To assess TLX ligand binding capacity, we created homology models of the TLX ligand binding domain (LBD. Results suggest that TLX belongs to an emerging class of NRs that lack LBD helices α1 and α2 and that it has potential to form a large open ligand binding pocket (LBP. Using a medium throughput screening strategy, we investigated direct binding of 20,000 compounds to purified human TLX protein and verified interactions with a secondary (orthogonal assay. We then assessed effects of verified binders on TLX activity using luciferase assays. As a result, we report identification of three compounds (ccrp1, ccrp2 and ccrp3 that bind to recombinant TLX protein with affinities in the high nanomolar to low micromolar range and enhance TLX transcriptional repressive activity. We conclude that TLX is druggable and propose that our lead compounds could serve as scaffolds to derive more potent ligands. While our ligands potentiate TLX repressive activity, the question of whether it is possible to develop ligands to de-repress TLX activity remains open.

  1. The human orphan nuclear receptor tailless (TLX, NR2E1) is druggable.

    Science.gov (United States)

    Benod, Cindy; Villagomez, Rosa; Filgueira, Carly S; Hwang, Peter K; Leonard, Paul G; Poncet-Montange, Guillaume; Rajagopalan, Senapathy; Fletterick, Robert J; Gustafsson, Jan-Åke; Webb, Paul

    2014-01-01

    Nuclear receptors (NRs) are an important group of ligand-dependent transcriptional factors. Presently, no natural or synthetic ligand has been identified for a large group of orphan NRs. Small molecules to target these orphan NRs will provide unique resources for uncovering regulatory systems that impact human health and to modulate these pathways with drugs. The orphan NR tailless (TLX, NR2E1), a transcriptional repressor, is a major player in neurogenesis and Neural Stem Cell (NSC) derived brain tumors. No chemical probes that modulate TLX activity are available, and it is not clear whether TLX is druggable. To assess TLX ligand binding capacity, we created homology models of the TLX ligand binding domain (LBD). Results suggest that TLX belongs to an emerging class of NRs that lack LBD helices α1 and α2 and that it has potential to form a large open ligand binding pocket (LBP). Using a medium throughput screening strategy, we investigated direct binding of 20,000 compounds to purified human TLX protein and verified interactions with a secondary (orthogonal) assay. We then assessed effects of verified binders on TLX activity using luciferase assays. As a result, we report identification of three compounds (ccrp1, ccrp2 and ccrp3) that bind to recombinant TLX protein with affinities in the high nanomolar to low micromolar range and enhance TLX transcriptional repressive activity. We conclude that TLX is druggable and propose that our lead compounds could serve as scaffolds to derive more potent ligands. While our ligands potentiate TLX repressive activity, the question of whether it is possible to develop ligands to de-repress TLX activity remains open.

  2. An rpoD gene sequence based evaluation of cultured Pseudomonas diversity on different growth media.

    Science.gov (United States)

    Ghyselinck, Jonas; Coorevits, An; Van Landschoot, Anita; Samyn, Emly; Heylen, Kim; De Vos, Paul

    2013-10-01

    The last decade has shown an increased interest in the utilization of bacteria for applications ranging from bioremediation to wastewater purification and promotion of plant growth. In order to extend the current number of micro-organism mediated applications, a continued quest for new agents is required. This study focused on the genus Pseudomonas, which is known to harbour strains with a very diverse set of interesting properties. The aim was to identify growth media that allow retrieval of a high Pseudomonas diversity, as such increasing the chance of isolating isolates with beneficial properties. Three cultivation media: trypticase soy agar (TSA), potato dextrose agar (PDA) and Pseudomonas isolation agar (PIA) were evaluated for their abilities to grow Pseudomonas strains. TSA and PDA were found to generate the largest Pseudomonas diversity. However, communities obtained with both media overlapped. Communities obtained with PIA, on the other hand, were unique. This indicated that the largest diversity is obtained by sampling from either PDA or TSA and from PIA in parallel. To evaluate biodiversity of the isolated Pseudomonas members on the media, an appropriate biomarker had to be identified. Hence, an introductory investigation of the taxonomic resolution of the 16S rRNA, rpoD, gyrB and rpoB genes was performed. The rpoD gene sequences not only had a high phylogenetic content and the highest taxonomic resolution amongst the genes investigated, it also had a gene phylogeny that related well with that of the 16S rRNA gene.

  3. Photodynamic antimicrobial therapy to inhibit pseudomonas aeruginosa of corneal isolates (Conference Presentation)

    Science.gov (United States)

    Durkee, Heather A.; Relhan, Nidhi; Arboleda, Alejandro; Halili, Francisco; De Freitas, Carolina; Alawa, Karam; Aguilar, Mariela C.; Amescua, Guillermo; Miller, Darlene; Parel, Jean-Marie

    2016-03-01

    Keratitis associated with Pseudomonas aeruginosa is difficult to manage. Treatment includes antibiotic eye drops, however, some strains of Pseudomonas aeruginosa are resistant. Current research efforts are focused on finding alternative and adjunct therapies to treat multi-drug resistant bacteria. One promising alternate technique is photodynamic therapy (PDT). The purpose of this study was to evaluate the effect of riboflavin- and rose bengal-mediated PDT on Pseudomonas aeruginosa keratitis isolates in vitro. Two isolates (S+U- and S-U+) of Pseudomonas aeruginosa were derived from keratitis patients and exposed to five experimental groups: (1) Control (dark, UV-A irradiation, 525nm irradiation); (2) 0.1% riboflavin (dark, UV-A irradiation); and (3) 0.1% rose bengal, (4) 0.05% rose bengal and (5) 0.01% rose bengal (dark, 525nm irradiation). Three days after treatment, in dark conditions of all concentration of riboflavin and rose bengal showed no inhibition in both S+U- and S-U+ strains of Pseudomonas aeruginosa. In 0.1% and 0.05% rose bengal irradiated groups, for both S+U- and S-U+ strains, there was complete inhibition of bacterial growth in the central 50mm zone corresponding to the diameter of the green light source. These in vitro results suggest that rose bengal photodynamic therapy may be an effective adjunct treatment for Pseudomonas aeruginosa keratitis.

  4. Pseudomonas kribbensis sp. nov., isolated from garden soils in Daejeon, Korea.

    Science.gov (United States)

    Chang, Dong-Ho; Rhee, Moon-Soo; Kim, Ji-Sun; Lee, Yookyung; Park, Mi Young; Kim, Haseong; Lee, Seung-Goo; Kim, Byoung-Chan

    2016-11-01

    Two bacterial strains, 46-1 and 46-2(T), were isolated from garden soil. These strains were observed to be aerobic, Gram-stain negative, rod-shaped, non-spore-forming, motile and catalase and oxidase positive. Phylogenetic analysis based on 16S rRNA gene sequences showed that the two strains shared 100 % sequence similarity with each other and belong to the genus Pseudomonas in the class Gammaproteobacteria. The concatenated 16S rRNA, gyrB, rpoB and rpoD gene sequences further confirmed that the isolates belong to the Pseudomonas koreensis subgroup (SG), with P. koreensis Ps 9-14(T), Pseudomonas moraviensis 1B4(T) and Pseudomonas granadensis F-278,770(T) as their close relatives (>96 % pairwise similarity). DNA-DNA hybridization with the closely related type strain P. koreensis SG revealed a low level of relatedness (15 %) in the isolates but it was a minor component (Pseudomonas, for which the name Pseudomonas kribbensis sp. nov. is proposed; the type strain is 46-2(T) (=KCTC 32541(T) = DSM 100278(T)).

  5. The Age Lipid A2E and Mitochondrial Dysfunction Synergistically Impair Phagocytosis by Retinal Pigment Epithelial Cells*

    Science.gov (United States)

    Vives-Bauza, Cristofol; Anand, Monika; Shirazi, Arash K.; Magrane, Jordi; Gao, Junping; Vollmer-Snarr, Heidi R.; Manfredi, Giovanni; Finnemann, Silvia C.

    2008-01-01

    Accumulation of indigestible lipofuscin and decreased mitochondrial energy production are characteristic age-related changes of post-mitotic retinal pigment epithelial (RPE) cells in the human eye. To test whether these two forms of age-related impairment have interdependent effects, we quantified the ATP-dependent phagocytic function of RPE cells loaded or not with the lipofuscin component A2E and inhibiting or not mitochondrial ATP synthesis either pharmacologically or genetically. We found that physiological levels of lysosomal A2E reduced mitochondrial membrane potential and inhibited oxidative phosphorylation (OXPHOS) of RPE cells. Furthermore, in media with physiological concentrations of glucose or pyruvate, A2E significantly inhibited phagocytosis. Antioxidants reversed these effects of A2E, suggesting that A2E damage is mediated by oxidative processes. Because mitochondrial mutations accumulate with aging, we generated novel genetic cellular models of RPE carrying mitochondrial DNA point mutations causing either moderate or severe mitochondrial dysfunction. Exploring these mutant RPE cells we found that, by itself, only the severe but not the moderate OXPHOS defect reduces phagocytosis. However, sub-toxic levels of lysosomal A2E are sufficient to reduce phagocytic activity of RPE with moderate OXPHOS defect and cause cell death of RPE with severe OXPHOS defect. Taken together, RPE cells rely on OXPHOS for phagocytosis when the carbon energy source is limited. Our results demonstrate that A2E accumulation exacerbates the effects of moderate mitochondrial dysfunction. They suggest that synergy of sub-toxic lysosomal and mitochondrial changes in RPE cells with age may cause RPE dysfunction that is known to contribute to human retinal diseases like age-related macular degeneration. PMID:18621729

  6. METABOLIC PECULIARITIES AT EXPERIMENTAL GENERALIZED PROCESS CAUSED BY PSEUDOMONAS AERUGINOSA

    Directory of Open Access Journals (Sweden)

    Popov М. М.

    2017-06-01

    Full Text Available System of free radical oxidation is a non-specific link of most of pathologic processes formation in organism. Enzimological studies allowing the definition of both organospecific violations and the state of biological membranes are of great interest in complex approach to the estimation of structural and metabolic peculiarities of organism in conditions of inflammatory pathology. Thus the purpose of the given study is the definition of metabolic state peculiarities at experimental generalized process caused by Pseudomonas aeruginosa. According to the results of the carried out studies the activity of the processes of lipids peroxidation in myocardium of infected animals rises: the content of MDA and DC is increased in comparison with intact animals while SH-groups content and catalase activity are decreased, i.e. the oxidative stress takes place in myocardium of infected animals which leads to energy-hungry state process which is also proved by AF – enzyme activity increase which implements hydrolysis of monophosphoric esteris and LDH – enzyme of anaerobic glуcolysis. Activity of AsAT, AlAT and γ-GTP is reliably higher which proves about the activation of protein biosynthesis into tissues which is connected with accelerated enzyme synthesis under the influence of inflammation mediators, i.e. compensatory reaction activation takes place. The similar picture is found in kidneys and liver: LPO under insufficiency of AOS, power-hungry state. The level of МСВ – integrated indicator of intoxication as well as LPO products grows in blood of infected experimental animals which proves about high level of inflammatory process and organism intoxication. Increasing of protein concentration of acute phase – haptoglobulin – also proves about high level of inflammatory process. High activity of LDG (cytoplasmatic enzyme proves about cytoplasmic membranes injury. The decrease of catalase activity and level of SH-groups of blood are found in

  7. Cytochrome P450 2E1 potentiates ethanol induction of hypoxia and HIF-1α in vivo.

    Science.gov (United States)

    Wang, Xiaodong; Wu, Defeng; Yang, Lili; Gan, Lixia; Cederbaum, Arthur I

    2013-10-01

    Ethanol induces hypoxia and elevates HIF-1α in the liver. CYP2E1 plays a role in the mechanisms by which ethanol generates oxidative stress, fatty liver, and liver injury. This study evaluated whether CYP2E1 contributes to ethanol-induced hypoxia and activation of HIF-1α in vivo and whether HIF-1α protects against or promotes CYP2E1-dependent toxicity in vitro. Wild-type (WT), CYP2E1-knock-in (KI), and CYP2E1 knockout (KO) mice were fed ethanol chronically; pair-fed controls received isocaloric dextrose. Ethanol produced liver injury in the KI mice to a much greater extent than in the WT and KO mice. Protein levels of HIF-1α and downstream targets of HIF-1α activation were elevated in the ethanol-fed KI mice compared to the WT and KO mice. Levels of HIF prolyl hydroxylase 2, which promotes HIF-1α degradation, were decreased in the ethanol-fed KI mice in association with the increases in HIF-1α. Hypoxia occurred in the ethanol-fed CYP2E1 KI mice as shown by an increased area of staining using the hypoxia-specific marker pimonidazole. Hypoxia was lower in the ethanol-fed WT mice and lowest in the ethanol-fed KO mice and all the dextrose-fed mice. In situ double staining showed that pimonidazole and CYP2E1 were colocalized to the same area of injury in the hepatic centrilobule. Increased protein levels of HIF-1α were also found after acute ethanol treatment of KI mice. Treatment of HepG2 E47 cells, which express CYP2E1, with ethanol plus arachidonic acid (AA) or ethanol plus buthionine sulfoximine (BSO), which depletes glutathione, caused loss of cell viability to a greater extent than in HepG2 C34 cells, which do not express CYP2E1. These treatments elevated protein levels of HIF-1α to a greater extent in E47 cells than in C34 cells. 2-Methoxyestradiol, an inhibitor of HIF-1α, blunted the toxic effects of ethanol plus AA and ethanol plus BSO in the E47 cells in association with inhibition of HIF-1α. The HIF-1α inhibitor also blocked the elevated oxidative

  8. Multimeric recombinant M2e protein-based ELISA: a significant improvement in differentiating avian influenza infected chickens from vaccinated ones.

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    Farshid Hadifar

    Full Text Available Killed avian influenza virus (AIV vaccines have been used to control H5N1 infections in countries where the virus is endemic. Distinguishing vaccinated from naturally infected birds (DIVA in such situations however, has become a major challenge. Recently, we introduced the recombinant ectodomain of the M2 protein (M2e of H5N1 subtype as a novel tool for an ELISA based DIVA test. Despite being antigenic in natural infection the monomer form of the M2e used in ELISA had limited antigenicity and consequently poor diagnostic capability. To address this shortcoming, we evaluated the use of four tandem copies of M2e (tM2e for increased efficiency of M2e antibody detection. The tM2e gene of H5N1 strain from Indonesia (A/Indonesia/CDC540/2006 was cloned into a pMAL- p4x expression vector and expressed in E.coli as a recombinant tM2e-MBP or M2e-MBP proteins. Both of these, M2e and tM2e antigens reacted with sera obtained from chickens following live H5N1 infection but not with sera from vaccinated birds. A significantly stronger M2e antibody reaction was observed with the tM2e compared to M2e antigen. Western blotting also supported the superiority of tM2e over M2e in detection of specific M2e antibodies against live H5N1 infection. Results from this study demonstrate that M2e tetramer is a better antigen than single M2e and could be more suitable for an ELISA based DIVA test.

  9. Synthesis and Antimycobacterial and Photosynthesis-Inhibiting Evaluation of 2-[(E-2-Substituted-ethenyl]-1,3-benzoxazoles

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    Ales Imramovsky

    2014-01-01

    Full Text Available A series of twelve 2-[(E-2-substituted-ethenyl]-1,3-benzoxazoles was designed. All the synthesized compounds were tested against three mycobacterial strains. The compounds were also evaluated for their ability to inhibit photosynthetic electron transport (PET in spinach (Spinacia oleracea L. chloroplasts. 2-[(E-2-(4-Methoxyphenylethenyl]-1,3-benzoxazole, 2-[(E-2-(2,3-dihydro-1-benzofuran-5-ylethenyl]-1,3-benzoxazole and 2-{(E-2-[4-(methylsulfanylphenyl]ethenyl}-1,3-benzoxazole showed the highest activity against M. tuberculosis, M. kansasii, and M. avium, and they demonstrated significantly higher activity against M. avium and M. kansasii than isoniazid. The PET-inhibiting activity of the most active ortho-substituted compound 2-[(E-2-(2-methoxyphenylethenyl]-1,3-benzoxazole was IC50 = 76.3 μmol/L, while the PET-inhibiting activity of para-substituted compounds was significantly lower. The site of inhibitory action of tested compounds is situated on the donor side of photosystem II. The structure-activity relationships are discussed.

  10. A Direct Quantitative Agar-Plate Based Assay for Analysis of Pseudomonas protegens PF-5 Degradation of Polyurethane Films (Postprint)

    Science.gov (United States)

    2014-10-02

    activity in Pseudomonas fluorescens CHA0. Mol. Plant - Microbe . Interact . 25, 1440e1449. Yang, X., Wang, S., Zhou, L., 2012. Effect of carbon source, C... Interactions between the Pf-5 colonies and thin polyurethane (PU) coatings on ZnSe coupons were evaluated for degradation using infrared spectroscopy...Small (1 mm diameter) colonies of Pseudomonas protegens Pf-5 (formerly Pseudomonas fluorescens Pf-5) were used for this work. Interactions between

  11. Dermal Wound Transcriptomic Responses to Infection with Pseudomonas aeruginosa versus Klebsiella pneumoniae in a Rabbit Ear Wound Model

    Science.gov (United States)

    2014-05-02

    Dermal wound transcriptomic responses to Infection with Pseudomonas aeruginosa versus Klebsiella pneumoniae in a rabbit ear wound model Kai P Leung Pt...with Klebsiella pneumoniae (Kp.) or Pseudomonas aeruginosa (P.o.) would indicate host responses associated with the worse healing of P.o. than Kp...responses to injection with Pseudomonas aeruginosa versus Klebsiella pneumoniae in a rabbit ear wound model 5a. CONTRACT NUMBER 5b. GRANT NUMBER

  12. N-acetylcysteine inhibit biofilms produced by Pseudomonas aeruginosa

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    Liu Youning

    2010-05-01

    Full Text Available Abstract Background Pseudomonas aeruginosa is a common pathogen in chronic respiratory tract infections. It typically makes a biofilm, which makes treatment of these infections difficult. In this study, we investigated the inhibitory effects of N-acetylcysteine (NAC on biofilms produced by P. aeruginosa. Results We found that minimum inhibitory concentrations (MICs of NAC for most isolates of P. aeruginosa were 10 to 40 mg/ml, the combination of NAC and ciprofloxacin (CIP demonstrated either synergy (50% or no interaction (50% against the P. aeruginosa strains. NAC at 0.5 mg/ml could detach mature P. aeruginosa biofilms. Disruption was proportional to NAC concentrations, and biofilms were completely disrupted at 10 mg/ml NAC. Analysis using COMSTAT software also showed that PAO1 biofilm biomass decreased and its heterogeneity increased as NAC concentration increased. NAC and ciprofloxacin showed significant killing of P. aeruginosa in biofilms at 2.5 mg/ml and > 2 MIC, respectively (p p P. aeruginosa also decreased by 27.64% and 44.59% at NAC concentrations of 0.5 mg/ml and 1 mg/ml. Conclusions NAC has anti-bacterial properties against P. aeruginosa and may detach P. aeruginosa biofilms. Use of NAC may be a new strategy for the treatment of biofilm-associated chronic respiratory infections due to P. aeruginosa, although it would be appropriate to conduct clinical studies to confirm this.

  13. Surface Sensing for Biofilm Formation in Pseudomonas aeruginosa

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    Chien-Yi Chang

    2018-01-01

    Full Text Available Aggregating and forming biofilms on biotic or abiotic surfaces are ubiquitous bacterial behaviors under various conditions. In clinical settings, persistent presence of biofilms increases the risks of healthcare-associated infections and imposes huge healthcare and economic burdens. Bacteria within biofilms are protected from external damage and attacks from the host immune system and can exchange genomic information including antibiotic-resistance genes. Dispersed bacterial cells from attached biofilms on medical devices or host tissues may also serve as the origin of further infections. Understanding how bacteria develop biofilms is pertinent to tackle biofilm-associated infections and transmission. Biofilms have been suggested as a continuum of growth modes for adapting to different environments, initiating from bacterial cells sensing their attachment to a surface and then switching cellular physiological status for mature biofilm development. It is crucial to understand bacterial gene regulatory networks and decision-making processes for biofilm formation upon initial surface attachment. Pseudomonas aeruginosa is one of the model microorganisms for studying bacterial population behaviors. Several hypotheses and studies have suggested that extracellular macromolecules and appendages play important roles in bacterial responses to the surface attachment. Here, I review recent studies on potential molecular mechanisms and signal transduction pathways for P. aeruginosa surface sensing.

  14. Pyoverdine, the Major Siderophore in Pseudomonas aeruginosa, Evades NGAL Recognition

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    Mary E. Peek

    2012-01-01

    Full Text Available Pseudomonas aeruginosa is the most common pathogen that persists in the cystic fibrosis lungs. Bacteria such as P. aeruginosa secrete siderophores (iron-chelating molecules and the host limits bacterial growth by producing neutrophil-gelatinase-associated lipocalin (NGAL that specifically scavenges bacterial siderophores, therefore preventing bacteria from establishing infection. P. aeruginosa produces a major siderophore known as pyoverdine, found to be important for bacterial virulence and biofilm development. We report that pyoverdine did not bind to NGAL, as measured by tryptophan fluorescence quenching, while enterobactin bound to NGAL effectively causing a strong response. The experimental data indicate that pyoverdine evades NGAL recognition. We then employed a molecular modeling approach to simulate the binding of pyoverdine to human NGAL using NGAL’s published crystal structures. The docking of pyoverdine to NGAL predicted nine different docking positions; however, neither apo- nor ferric forms of pyoverdine docked into the ligand-binding site in the calyx of NGAL where siderophores are known to bind. The molecular modeling results offer structural support that pyoverdine does not bind to NGAL, confirming the results obtained in the tryptophan quenching assay. The data suggest that pyoverdine is a stealth siderophore that evades NGAL recognition allowing P. aeruginosa to establish chronic infections in CF lungs.

  15. Effect of methylglyoxal on multidrug-resistant Pseudomonas aeruginosa

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    Katsuhiko eHayashi

    2014-04-01

    Full Text Available Honey has a complex chemistry, and its broad-spectrum antimicrobial activity varies with floral source, climate, and harvesting conditions. Methylglyoxal was identified as the dominant antibacterial component of manuka honey. Although it has been known that methylglyoxal has antibacterial activity against gram-positive bacteria, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus, there is not much information describing its activity against gram-negative bacteria. In this study, we report the effect of methylglyoxal against multidrug-resistant Pseudomonas aeruginosa (MDRP using 53 clinically isolated strains. We also assessed the effect of deleting the five multidrug efflux systems in P. aeruginosa, as well as the efflux systems in Escherichia coli and Salmonella enterica serovar Typhimurium, on MICs of methylglyoxal. Our results indicate that methylglyoxal inhibits the growth of MDRP at concentrations of 128–512 µg/ml (1.7–7.1 mM and is not recognized by drug efflux systems.

  16. [Cervical lymphoadenopathy due to Pseudomonas aeruginosa following mesotherapy].

    Science.gov (United States)

    Shaladi, Ali Muftah; Crestani, Francesco; Bocchi, Anna; Saltari, Maria Rita; Piva, Bruno; Tartari, Stefano

    2009-09-01

    Mesotherapy is a treatment method devised for controlling several diseases by means of subcutaneous microinjections given at or around the affected areas at short time intervals. It is used to treat a variety of medical conditions, amongst which all orthopaedic diseases and rheumatic pain. Mesotherapy is especially indicated for neck pain. The mechanism of action is twofold: a pharmacological effect due to the drug administered, and a reflexogenic effect, the skin containing many nerve endings that are sensitive to the mechanical action of the needle. Although this therapy is safe, like any other medical intervention it cannot be considered free of complications that may occur, such as allergies, haematomas, bruising, wheals, granulomas and telangiectasias. Infective complications are also possible, due to pathogenic bacteria that are inoculated through contamination of products, of the materials used for the procedure or even from germs on the skin. We present the case of a patient who had cervical lymphadenopathy due to Pseudomonas aeruginosa after mesotherapy treatment for neck pain.

  17. Pseudomonas fluorescens subsp. cellulosa: an alternative model for bacterial cellulase.

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    Hazlewood, G P; Laurie, J I; Ferreira, L M; Gilbert, H J

    1992-03-01

    Pseudomonas fluorescens subsp. cellulosa, a Gram-negative soil bacterium, can utilize crystalline cellulose or xylan as main sources of carbon and energy. Synthesis of endoglucanases and xylanases is induced by Avicel, filter paper, carboxymethylcellulose or xylan and is repressed by cellobiose, glucose or xylose. These enzymes are secreted into the culture supernatant fluid and do not form aggregates or associate with the cell surface. Cells of Ps. fluorescens subsp. cellulosa do not adhere to cellulose. In cultures containing Avicel or filter paper, a significant proportion of the secreted cellulase and xylanase activities becomes tightly bound to the insoluble cellulose. Western blotting has revealed that endoglucanase B, xylanase A and a cellodextrinase encoded by genes previously isolated from Ps. fluorescens subsp. cellulosa and expressed in Escherichia coli, are synthesized by the pseudomonad under a variety of conditions. These enzymes appear to be post-translationally modified, probably through glycosylation. Overall, it appears that the cellulase/hemicellulase system of Ps. fluorescens subsp. cellulosa differs from the model established for celluloytic anaerobes such as Clostridium thermocellum.

  18. Ginger Extract Inhibits Biofilm Formation by Pseudomonas aeruginosa PA14

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    Kim, Han-Shin; Park, Hee-Deung

    2013-01-01

    Bacterial biofilm formation can cause serious problems in clinical and industrial settings, which drives the development or screening of biofilm inhibitors. Some biofilm inhibitors have been screened from natural products or modified from natural compounds. Ginger has been used as a medicinal herb to treat infectious diseases for thousands of years, which leads to the hypothesis that it may contain chemicals inhibiting biofilm formation. To test this hypothesis, we evaluated ginger’s ability to inhibit Pseudomonas aeruginosa PA14 biofilm formation. A static biofilm assay demonstrated that biofilm development was reduced by 39–56% when ginger extract was added to the culture. In addition, various phenotypes were altered after ginger addition of PA14. Ginger extract decreased production of extracellular polymeric substances. This finding was confirmed by chemical analysis and confocal laser scanning microscopy. Furthermore, ginger extract formed noticeably less rugose colonies on agar plates containing Congo red and facilitated swarming motility on soft agar plates. The inhibition of biofilm formation and the altered phenotypes appear to be linked to a reduced level of a second messenger, bis-(3′-5′)-cyclic dimeric guanosine monophosphate. Importantly, ginger extract inhibited biofilm formation in both Gram-positive and Gram-negative bacteria. Also, surface biofilm cells formed with ginger extract detached more easily with surfactant than did those without ginger extract. Taken together, these findings provide a foundation for the possible discovery of a broad spectrum biofilm inhibitor. PMID:24086697

  19. Bacteriocins and the assembly of natural Pseudomonas fluorescens populations.

    Science.gov (United States)

    Bruce, J B; West, S A; Griffin, A S

    2017-02-01

    When competing for space and resources, bacteria produce toxins known as bacteriocins to gain an advantage over competitors. Recent studies in the laboratory have confirmed theoretical predictions that bacteriocin production can determine coexistence, by eradicating sensitive competitors or driving the emergence of resistant genotypes. However, there is currently limited evidence that bacteriocin-mediated competition influences the coexistence and distribution of genotypes in natural environments, and what factors drive interactions towards inhibition remain unclear. Using natural soil populations of Pseudomonas fluorescens, we assessed the ability of the isolates to inhibit one another with respect to spatial proximity in the field, genetic similarity and niche overlap. The majority of isolates were found to produce bacteriocins; however, widespread resistance between coexisting isolates meant relatively few interactions resulted in inhibition. When inhibition did occur, it occurred more frequently between ecologically similar isolates. However, in contrast with results from other natural populations, we found no relationship between the frequency of inhibition and the genetic similarity of competitors. Our results suggest that bacteriocin production plays an important role in mediating competition over resources in natural settings and, by selecting for isolates resistant to local bacteriocin production, can influence the assembly of natural populations of P. fluorescens. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  20. PA3297 Counteracts Antimicrobial Effects of Azithromycin in Pseudomonas aeruginosa

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    Hao eTan

    2016-03-01

    Full Text Available Pseudomonas aeruginosa causes acute and chronic infections in human. Its increasing resistance to antibiotics requires alternative treatments that are more effective than available strategies. Among the alternatives is the unconventional usage of conventional antibiotics, of which the macrolide antibiotic azithromycin (AZM provides a paradigmatic example. AZM therapy is associated with a small but consistent improvement in respiratory function of cystic fibrosis (CF patients suffering from chronic P. aeruginosa infection. Besides immunomodulating activities, AZM represses bacterial genes involved in virulence, quorum sensing, biofilm formation, and motility, all of which are due to stalling of ribosome and depletion of cellular tRNA pool. However, how P. aeruginosa responds to and counteracts the effects of AZM remain elusive. Here we found that deficiency of PA3297, a gene encoding a DEAH-box helicase, intensified AZM-mediated bacterial killing, suppression of pyocyanin production and swarming motility, and hypersusceptibility to hydrogen peroxide. We demonstrated that expression of PA3297 is induced by the interaction between AZM and ribosome. Importantly, mutation of PA3297 resulted in elevated levels of unprocessed 23S-5S rRNA in the presence of AZM, which might lead to increased susceptibility to AZM-mediated effects. Our results revealed one of the bacterial responses in counteracting the detrimental effects of AZM.